diff --git a/libcxx/cmake/Modules/CheckLibcxxAtomic.cmake b/libcxx/cmake/Modules/CheckLibcxxAtomic.cmake
index 98862d42397b688a21d00528c410e0a411298ee4..1e6e5e6376620a7aa447c780e94791727cf92b29 100644
--- a/libcxx/cmake/Modules/CheckLibcxxAtomic.cmake
+++ b/libcxx/cmake/Modules/CheckLibcxxAtomic.cmake
@@ -24,7 +24,7 @@ function(check_cxx_atomics varname)
 #include <atomic>
 std::atomic<uintptr_t> x;
 std::atomic<uintmax_t> y;
-int main() {
+int main(int, char**) {
   return x + y;
 }
 " ${varname})
diff --git a/libcxx/docs/DesignDocs/DebugMode.rst b/libcxx/docs/DesignDocs/DebugMode.rst
index 3b997d44607011383cf73b28cf930038ee16be57..1ce438d5316ce5a23a98440a454aab0a154654d5 100644
--- a/libcxx/docs/DesignDocs/DebugMode.rst
+++ b/libcxx/docs/DesignDocs/DebugMode.rst
@@ -53,7 +53,7 @@ assertion handler as follows:
 
   #define _LIBCPP_DEBUG 1
   #include <string>
-  int main() {
+  int main(int, char**) {
     std::__libcpp_debug_function = std::__libcpp_throw_debug_function;
     try {
       std::string::iterator bad_it;
diff --git a/libcxx/docs/DesignDocs/FileTimeType.rst b/libcxx/docs/DesignDocs/FileTimeType.rst
index 488ff174b341d79c9cc9aed9c78cfc648bf9bb6d..f1e9edd87354af1cf1e6c1895047aed5829c0185 100644
--- a/libcxx/docs/DesignDocs/FileTimeType.rst
+++ b/libcxx/docs/DesignDocs/FileTimeType.rst
@@ -119,7 +119,7 @@ to throw in cases where the user was confident the call should succeed. (See bel
     set_file_times("/tmp/foo", new_times); // OK, supported by most FSes
   }
 
-  int main() {
+  int main(int, char**) {
     path p = "/tmp/foo";
     file_status st = status(p);
     if (!exists(st) || !is_regular_file(st))
@@ -128,6 +128,7 @@ to throw in cases where the user was confident the call should succeed. (See bel
       return 1;
     // It seems reasonable to assume this call should succeed.
     file_time_type tp = last_write_time(p); // BAD! Throws value_too_large.
+    return 0;
   }
 
 
diff --git a/libcxx/test/libcxx/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle.cxx1z.pass.cpp b/libcxx/test/libcxx/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle.cxx1z.pass.cpp
index 926ee40f00d2b3fc39a74ad72806f749e267a901..0b55ae9507a7519e28125ececb55c2ca0d05f52c 100644
--- a/libcxx/test/libcxx/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle.cxx1z.pass.cpp
+++ b/libcxx/test/libcxx/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle.cxx1z.pass.cpp
@@ -39,10 +39,12 @@ struct gen
 };
 
 
-int main()
+int main(int, char**)
 {
     std::vector<int> v;
     std::random_shuffle(v.begin(), v.end());
     gen r;
     std::random_shuffle(v.begin(), v.end(), r);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle.depr_in_cxx14.fail.cpp b/libcxx/test/libcxx/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle.depr_in_cxx14.fail.cpp
index aca87ffb3c501f936a1618228deb57c4259c0b9a..7c187edaeec9918fc7d77b7dc9af35ffbd6a4f6f 100644
--- a/libcxx/test/libcxx/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle.depr_in_cxx14.fail.cpp
+++ b/libcxx/test/libcxx/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle.depr_in_cxx14.fail.cpp
@@ -40,10 +40,12 @@ struct gen
 };
 
 
-int main()
+int main(int, char**)
 {
     int v[1] = {1};
     std::random_shuffle(&v[0], &v[1]); // expected-error{{'random_shuffle<int *>' is deprecated}}
     gen r;
     std::random_shuffle(&v[0], &v[1], r); // expected-error{{'random_shuffle<int *, gen &>' is deprecated}}
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/algorithms/debug_less.pass.cpp b/libcxx/test/libcxx/algorithms/debug_less.pass.cpp
index f5b2796fd4daaf2d90e7c7eac6a5c2e91bb08010..247e07f06e036227a59bc9224e5e0f6f05cdd104 100644
--- a/libcxx/test/libcxx/algorithms/debug_less.pass.cpp
+++ b/libcxx/test/libcxx/algorithms/debug_less.pass.cpp
@@ -210,8 +210,10 @@ void test_upper_and_lower_bound() {
     }
 }
 
-int main() {
+int main(int, char**) {
     test_passing();
     test_failing();
     test_upper_and_lower_bound();
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/algorithms/half_positive.pass.cpp b/libcxx/test/libcxx/algorithms/half_positive.pass.cpp
index 1434b3e9a4c441bcfd6ba0777c18de229e462f67..ec2d57c9dd9f73e076e226ffa3651bc3206c736c 100644
--- a/libcxx/test/libcxx/algorithms/half_positive.pass.cpp
+++ b/libcxx/test/libcxx/algorithms/half_positive.pass.cpp
@@ -28,7 +28,7 @@ TEST_CONSTEXPR bool test(IntType max_v = IntType(std::numeric_limits<UnderlyingT
 
 }  // namespace
 
-int main()
+int main(int, char**)
 {
     {
         assert(test<char>());
@@ -52,4 +52,6 @@ int main()
 #endif  // !defined(_LIBCPP_HAS_NO_INT128)
     }
 #endif // TEST_STD_VER >= 11
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/algorithms/version.pass.cpp b/libcxx/test/libcxx/algorithms/version.pass.cpp
index 4fcd03674c91c283489464a70d8183fc83dbd5bb..e7d368789421ab68f4e26760f82fd355f48c8150 100644
--- a/libcxx/test/libcxx/algorithms/version.pass.cpp
+++ b/libcxx/test/libcxx/algorithms/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/atomics/atomics.align/align.pass.sh.cpp b/libcxx/test/libcxx/atomics/atomics.align/align.pass.sh.cpp
index 7162493c5f3b8e64ce51887370b34d9cd84af8cf..16badab8490a8a924450892522960962bb4c6a27 100644
--- a/libcxx/test/libcxx/atomics/atomics.align/align.pass.sh.cpp
+++ b/libcxx/test/libcxx/atomics/atomics.align/align.pass.sh.cpp
@@ -35,7 +35,7 @@ template <typename T> struct atomic_test : public std::__atomic_base<T> {
   }
 };
 
-int main() {
+int main(int, char**) {
 
 // structs and unions can't be defined in the template invocation.
 // Work around this with a typedef.
@@ -89,4 +89,6 @@ int main() {
   CHECK_ALIGNMENT(struct LLIArr16 { long long int i[16]; });
   CHECK_ALIGNMENT(struct Padding { char c; /* padding */ long long int i; });
   CHECK_ALIGNMENT(union IntFloat { int i; float f; });
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/atomics/atomics.flag/init_bool.pass.cpp b/libcxx/test/libcxx/atomics/atomics.flag/init_bool.pass.cpp
index 7006a86d451c8abeebea34b9d54e4e331889b6a6..2919fb666bc5a074cf384e352bccc1672252e3ae 100644
--- a/libcxx/test/libcxx/atomics/atomics.flag/init_bool.pass.cpp
+++ b/libcxx/test/libcxx/atomics/atomics.flag/init_bool.pass.cpp
@@ -27,7 +27,7 @@ X x;
 std::atomic_flag global = ATOMIC_FLAG_INIT;
 #endif
 
-int main()
+int main(int, char**)
 {
 #if TEST_STD_VER >= 11
     assert(global.test_and_set() == 1);
@@ -40,4 +40,6 @@ int main()
         std::atomic_flag f(true);
         assert(f.test_and_set() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/atomics/diagnose_invalid_memory_order.fail.cpp b/libcxx/test/libcxx/atomics/diagnose_invalid_memory_order.fail.cpp
index 2869bf96e88463aad653bfe0172ee3fa0c6eedbd..7bc21851b712c50da99d430986c967e87064596f 100644
--- a/libcxx/test/libcxx/atomics/diagnose_invalid_memory_order.fail.cpp
+++ b/libcxx/test/libcxx/atomics/diagnose_invalid_memory_order.fail.cpp
@@ -19,7 +19,7 @@
 
 #include <atomic>
 
-int main() {
+int main(int, char**) {
     std::atomic<int> x(42);
     volatile std::atomic<int>& vx = x;
     int val1 = 1; ((void)val1);
@@ -124,4 +124,6 @@ int main() {
         std::atomic_compare_exchange_strong_explicit(&x, &val1, val2, std::memory_order_seq_cst, std::memory_order_acquire);
         std::atomic_compare_exchange_strong_explicit(&x, &val1, val2, std::memory_order_seq_cst, std::memory_order_seq_cst);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/atomics/libcpp-has-no-threads.fail.cpp b/libcxx/test/libcxx/atomics/libcpp-has-no-threads.fail.cpp
index 27ae2092933dcaa05b149d9cbc31207e67351563..6ee09e206467f5c90f2733ff5b3f65102eecb419 100644
--- a/libcxx/test/libcxx/atomics/libcpp-has-no-threads.fail.cpp
+++ b/libcxx/test/libcxx/atomics/libcpp-has-no-threads.fail.cpp
@@ -18,6 +18,8 @@
 
 #include <atomic>
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/atomics/libcpp-has-no-threads.pass.cpp b/libcxx/test/libcxx/atomics/libcpp-has-no-threads.pass.cpp
index 41fbe287909f6b64bcb5dbcb4bf2b6c8eca096e1..af2d55e1a4a3d737ae3aa27e9cea5921fdaa424b 100644
--- a/libcxx/test/libcxx/atomics/libcpp-has-no-threads.pass.cpp
+++ b/libcxx/test/libcxx/atomics/libcpp-has-no-threads.pass.cpp
@@ -12,6 +12,8 @@
    'libcpp-has-no-threads' is available iff _LIBCPP_HAS_NO_THREADS is defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/atomics/version.pass.cpp b/libcxx/test/libcxx/atomics/version.pass.cpp
index 5d89bc575a3f87ded41448290104e1d4c5edc0d4..48114a3e5db6d323df1669b6cfe6c30bea0eebaf 100644
--- a/libcxx/test/libcxx/atomics/version.pass.cpp
+++ b/libcxx/test/libcxx/atomics/version.pass.cpp
@@ -16,6 +16,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/associative/map/version.pass.cpp b/libcxx/test/libcxx/containers/associative/map/version.pass.cpp
index da33a03def476b58b0d9194a630d24001044f4f5..8a498c60dbf6cb65a327c8036a77dee610d26aee 100644
--- a/libcxx/test/libcxx/containers/associative/map/version.pass.cpp
+++ b/libcxx/test/libcxx/containers/associative/map/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/associative/non_const_comparator.fail.cpp b/libcxx/test/libcxx/containers/associative/non_const_comparator.fail.cpp
index 23c6ee8a28ba7b95a644eec73a854aadf8b2fda0..432e7c08d14c6e2824eeb80885ba67672e5dedaa 100644
--- a/libcxx/test/libcxx/containers/associative/non_const_comparator.fail.cpp
+++ b/libcxx/test/libcxx/containers/associative/non_const_comparator.fail.cpp
@@ -22,7 +22,7 @@ struct BadCompare {
   }
 };
 
-int main() {
+int main(int, char**) {
   static_assert(!std::__invokable<BadCompare const&, int const&, int const&>::value, "");
   static_assert(std::__invokable<BadCompare&, int const&, int const&>::value, "");
 
@@ -44,4 +44,6 @@ int main() {
     using C = std::multimap<long, int, BadCompare>;
     C s;
   }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/associative/set/version.pass.cpp b/libcxx/test/libcxx/containers/associative/set/version.pass.cpp
index 57420bae47499645a8ee67e3e7c1cde939e51845..b0d9abd6ac789934ed61d76aee615653cdf2633e 100644
--- a/libcxx/test/libcxx/containers/associative/set/version.pass.cpp
+++ b/libcxx/test/libcxx/containers/associative/set/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/associative/tree_balance_after_insert.pass.cpp b/libcxx/test/libcxx/containers/associative/tree_balance_after_insert.pass.cpp
index 8f17dbba7708765147a8bbf6fb1e48c981e69f70..e178a408fb7236f1150513e655bf038b88ded21b 100644
--- a/libcxx/test/libcxx/containers/associative/tree_balance_after_insert.pass.cpp
+++ b/libcxx/test/libcxx/containers/associative/tree_balance_after_insert.pass.cpp
@@ -1608,11 +1608,13 @@ test5()
     assert(h.__is_black_ == true);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
     test3();
     test4();
     test5();
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/associative/tree_key_value_traits.pass.cpp b/libcxx/test/libcxx/containers/associative/tree_key_value_traits.pass.cpp
index 3b5ba7d2a1759ca8feefe2e1012a752c8ec3049b..12289c84a9cc30cf4a9c9d3b0103d475dd9b4e03 100644
--- a/libcxx/test/libcxx/containers/associative/tree_key_value_traits.pass.cpp
+++ b/libcxx/test/libcxx/containers/associative/tree_key_value_traits.pass.cpp
@@ -53,6 +53,8 @@ void testKeyValueTrait() {
   }
 }
 
-int main() {
+int main(int, char**) {
   testKeyValueTrait();
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/associative/tree_left_rotate.pass.cpp b/libcxx/test/libcxx/containers/associative/tree_left_rotate.pass.cpp
index c7f136c8cb138130a8825c2c28eefc8f68673371..5f775c3f6afed7e0fe29e21c59ae7f3c9aa75933 100644
--- a/libcxx/test/libcxx/containers/associative/tree_left_rotate.pass.cpp
+++ b/libcxx/test/libcxx/containers/associative/tree_left_rotate.pass.cpp
@@ -93,8 +93,10 @@ test2()
     assert(c.__right_ == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/associative/tree_remove.pass.cpp b/libcxx/test/libcxx/containers/associative/tree_remove.pass.cpp
index b2c814dd76b3e3ea4e2af82372e6c33895295d6d..c3ec20c55c15a452c3a2d36cad48feeaec175cd2 100644
--- a/libcxx/test/libcxx/containers/associative/tree_remove.pass.cpp
+++ b/libcxx/test/libcxx/containers/associative/tree_remove.pass.cpp
@@ -1641,10 +1641,12 @@ test4()
     assert(root.__is_black_ == false);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
     test3();
     test4();
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/associative/tree_right_rotate.pass.cpp b/libcxx/test/libcxx/containers/associative/tree_right_rotate.pass.cpp
index bcaf71f0b01907028779c3c35147a2fe6270d731..5332d7b16b6d6e7fd72058709f9441777c66f3a7 100644
--- a/libcxx/test/libcxx/containers/associative/tree_right_rotate.pass.cpp
+++ b/libcxx/test/libcxx/containers/associative/tree_right_rotate.pass.cpp
@@ -93,8 +93,10 @@ test2()
     assert(c.__right_ == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/associative/undef_min_max.pass.cpp b/libcxx/test/libcxx/containers/associative/undef_min_max.pass.cpp
index 8ebd8a4ae213cc8b9d51566edcf037813aa91825..53dd87871d3098ddb74aa28e016ceb5f890c4997 100644
--- a/libcxx/test/libcxx/containers/associative/undef_min_max.pass.cpp
+++ b/libcxx/test/libcxx/containers/associative/undef_min_max.pass.cpp
@@ -15,7 +15,9 @@
 
 #include <map>
 
-int main() {
+int main(int, char**) {
   std::map<int, int> m;
   ((void)m);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/container.adaptors/queue/version.pass.cpp b/libcxx/test/libcxx/containers/container.adaptors/queue/version.pass.cpp
index 87d907a5a2f105dc0273f1a135224c52ace8a50d..353c091795cc13875097f6dfa17354268ec2339e 100644
--- a/libcxx/test/libcxx/containers/container.adaptors/queue/version.pass.cpp
+++ b/libcxx/test/libcxx/containers/container.adaptors/queue/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/container.adaptors/stack/version.pass.cpp b/libcxx/test/libcxx/containers/container.adaptors/stack/version.pass.cpp
index 00ed12c064239f7681bcde2ea4ca485aa74d8ddb..e8da8c52b735909ea4e51bfb1d885402538acece 100644
--- a/libcxx/test/libcxx/containers/container.adaptors/stack/version.pass.cpp
+++ b/libcxx/test/libcxx/containers/container.adaptors/stack/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/gnu_cxx/hash_map.pass.cpp b/libcxx/test/libcxx/containers/gnu_cxx/hash_map.pass.cpp
index 9470a9e31df03de0bc9103827a6e560d9e58dd58..12529e0f1ac242adc701e6f3e647b4f8542b1959 100644
--- a/libcxx/test/libcxx/containers/gnu_cxx/hash_map.pass.cpp
+++ b/libcxx/test/libcxx/containers/gnu_cxx/hash_map.pass.cpp
@@ -17,9 +17,11 @@ namespace __gnu_cxx {
 template class hash_map<int, int>;
 }
 
-int main() {
+int main(int, char**) {
   typedef __gnu_cxx::hash_map<int, int> Map;
   Map m;
   Map m2(m);
   ((void)m2);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/gnu_cxx/hash_set.pass.cpp b/libcxx/test/libcxx/containers/gnu_cxx/hash_set.pass.cpp
index cd6cfeb0a9a43a728af98027160258859245497a..e4fa9886371564ec4dcab929279cb369616eeaf8 100644
--- a/libcxx/test/libcxx/containers/gnu_cxx/hash_set.pass.cpp
+++ b/libcxx/test/libcxx/containers/gnu_cxx/hash_set.pass.cpp
@@ -17,9 +17,11 @@ namespace __gnu_cxx {
 template class hash_set<int>;
 }
 
-int main() {
+int main(int, char**) {
   typedef __gnu_cxx::hash_set<int> Set;
   Set s;
   Set s2(s);
   ((void)s2);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/array/array.zero/db_back.pass.cpp b/libcxx/test/libcxx/containers/sequences/array/array.zero/db_back.pass.cpp
index 3f1084c47d4cb71417dfa0457f635ff305c1fe8d..3c31911666233dd3cdcda176accd7c5b64ef64bb 100644
--- a/libcxx/test/libcxx/containers/sequences/array/array.zero/db_back.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/array/array.zero/db_back.pass.cpp
@@ -29,7 +29,7 @@ inline bool CheckDebugThrows(Array& Arr) {
   return false;
 }
 
-int main()
+int main(int, char**)
 {
   {
     typedef std::array<int, 0> C;
@@ -45,4 +45,6 @@ int main()
     assert(CheckDebugThrows(c));
     assert(CheckDebugThrows(cc));
   }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/array/array.zero/db_front.pass.cpp b/libcxx/test/libcxx/containers/sequences/array/array.zero/db_front.pass.cpp
index 6fd053dd6b57ffe2c5d3a021434a27c124af2e6a..9f6f09f983d7f55bd574c29e3ee14bf8f805427b 100644
--- a/libcxx/test/libcxx/containers/sequences/array/array.zero/db_front.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/array/array.zero/db_front.pass.cpp
@@ -29,7 +29,7 @@ inline bool CheckDebugThrows(Array& Arr) {
   return false;
 }
 
-int main()
+int main(int, char**)
 {
   {
     typedef std::array<int, 0> C;
@@ -45,4 +45,6 @@ int main()
     assert(CheckDebugThrows(c));
     assert(CheckDebugThrows(cc));
   }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/array/array.zero/db_indexing.pass.cpp b/libcxx/test/libcxx/containers/sequences/array/array.zero/db_indexing.pass.cpp
index fadc22810278093f7b6de4efb113e784818f2573..cb5e99b2924c9f7c39f3ecc31e0652c569a100e2 100644
--- a/libcxx/test/libcxx/containers/sequences/array/array.zero/db_indexing.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/array/array.zero/db_indexing.pass.cpp
@@ -29,7 +29,7 @@ inline bool CheckDebugThrows(Array& Arr, size_t Index) {
   return false;
 }
 
-int main()
+int main(int, char**)
 {
   {
     typedef std::array<int, 0> C;
@@ -49,4 +49,6 @@ int main()
     assert(CheckDebugThrows(cc, 0));
     assert(CheckDebugThrows(cc, 1));
   }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/array/version.pass.cpp b/libcxx/test/libcxx/containers/sequences/array/version.pass.cpp
index 21eb2576476c0b0434510bcee5e18ef517124fb2..29b15ad3e374f02bd87336a3c4bf875deeaca79c 100644
--- a/libcxx/test/libcxx/containers/sequences/array/version.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/array/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/deque/incomplete.pass.cpp b/libcxx/test/libcxx/containers/sequences/deque/incomplete.pass.cpp
index 3c5528d280c4fb65fd8d235f8fbe922462c07936..8179768d586f622a4048cc485b61f1f4e3a25049 100644
--- a/libcxx/test/libcxx/containers/sequences/deque/incomplete.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/deque/incomplete.pass.cpp
@@ -22,10 +22,12 @@ struct A {
   std::deque<A>::reverse_iterator it2;
 };
 
-int main()
+int main(int, char**)
 {
   A a;
   assert(a.d.size() == 0);
   a.it = a.d.begin();
   a.it2 = a.d.rend();
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/deque/pop_back_empty.pass.cpp b/libcxx/test/libcxx/containers/sequences/deque/pop_back_empty.pass.cpp
index 2b87e53b9211eed4583428fd9fd0203034756f51..169c0f72d6de690771d0b69b16f267ed74a252bb 100644
--- a/libcxx/test/libcxx/containers/sequences/deque/pop_back_empty.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/deque/pop_back_empty.pass.cpp
@@ -16,10 +16,12 @@
 #include <deque>
 
 
-int main() {
+int main(int, char**) {
     std::deque<int> q;
     q.push_back(0);
     q.pop_back();
     q.pop_back();
     std::exit(1);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/deque/version.pass.cpp b/libcxx/test/libcxx/containers/sequences/deque/version.pass.cpp
index 12256878a3987394e1515e8459b476bbaf733ab5..8f05025f1aabadbb1c45b831dc12319d7542b7e2 100644
--- a/libcxx/test/libcxx/containers/sequences/deque/version.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/deque/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/forwardlist/version.pass.cpp b/libcxx/test/libcxx/containers/sequences/forwardlist/version.pass.cpp
index 7e61bde5c58dd3b90c0a300a4e12c0194ca7eec2..cbe6d5821c152ab822093a85ff78e65f58cb3485 100644
--- a/libcxx/test/libcxx/containers/sequences/forwardlist/version.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/forwardlist/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/list/list.cons/db_copy.pass.cpp b/libcxx/test/libcxx/containers/sequences/list/list.cons/db_copy.pass.cpp
index 62695f8f84d301485264c811e48b54ebbbe5199a..da0eb5ce0c3032e486895161efb61936c5309f2f 100644
--- a/libcxx/test/libcxx/containers/sequences/list/list.cons/db_copy.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/list/list.cons/db_copy.pass.cpp
@@ -19,7 +19,7 @@
 #include <cstdlib>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::list<int> l1;
     l1.push_back(1); l1.push_back(2); l1.push_back(3);
@@ -27,4 +27,6 @@ int main()
     std::list<int> l2 = l1;
     l2.erase(i);
     assert(false);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/list/list.cons/db_move.pass.cpp b/libcxx/test/libcxx/containers/sequences/list/list.cons/db_move.pass.cpp
index 02306eb8804ffa6568271104b2f8abd3d1cf7d0c..dcd05ec419bc7a0d2018c593efd89764f22ac3e9 100644
--- a/libcxx/test/libcxx/containers/sequences/list/list.cons/db_move.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/list/list.cons/db_move.pass.cpp
@@ -25,10 +25,12 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     std::list<int> l1 = {1, 2, 3};
     std::list<int>::iterator i = l1.begin();
     std::list<int> l2 = std::move(l1);
     assert(*l2.erase(i) == 2);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/list/list.modifiers/emplace_db1.pass.cpp b/libcxx/test/libcxx/containers/sequences/list/list.modifiers/emplace_db1.pass.cpp
index 9554fd8bc42c682b2cd87fc4fd3cabf200200de0..b570fef66a08ff4c71d4ee88003772930ddcfa6c 100644
--- a/libcxx/test/libcxx/containers/sequences/list/list.modifiers/emplace_db1.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/list/list.modifiers/emplace_db1.pass.cpp
@@ -37,10 +37,12 @@ public:
     double getd() const {return d_;}
 };
 
-int main()
+int main(int, char**)
 {
     std::list<A> c1;
     std::list<A> c2;
     std::list<A>::iterator i = c1.emplace(c2.cbegin(), 2, 3.5);
     assert(false);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/list/list.modifiers/erase_iter_db1.pass.cpp b/libcxx/test/libcxx/containers/sequences/list/list.modifiers/erase_iter_db1.pass.cpp
index 6fa81ff47bab3e489c0b76e219a0b8b3c98a28e5..c573bf7bed6652766068f890104f04e0647d081a 100644
--- a/libcxx/test/libcxx/containers/sequences/list/list.modifiers/erase_iter_db1.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/list/list.modifiers/erase_iter_db1.pass.cpp
@@ -20,11 +20,13 @@
 #include <cassert>
 #include <cstdlib>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {1, 2, 3};
     std::list<int> l1(a1, a1+3);
     std::list<int>::const_iterator i = l1.end();
     l1.erase(i);
     assert(false);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/list/list.modifiers/erase_iter_db2.pass.cpp b/libcxx/test/libcxx/containers/sequences/list/list.modifiers/erase_iter_db2.pass.cpp
index 45d163a99501220577452840e3c5efe198dfe4d4..65cc4b8f8d6462063bb1270c606df4d7b78e39bb 100644
--- a/libcxx/test/libcxx/containers/sequences/list/list.modifiers/erase_iter_db2.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/list/list.modifiers/erase_iter_db2.pass.cpp
@@ -20,7 +20,7 @@
 #include <cassert>
 #include <cstdlib>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {1, 2, 3};
     std::list<int> l1(a1, a1+3);
@@ -28,4 +28,6 @@ int main()
     std::list<int>::const_iterator i = l2.begin();
     l1.erase(i);
     assert(false);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/list/list.modifiers/erase_iter_iter_db1.pass.cpp b/libcxx/test/libcxx/containers/sequences/list/list.modifiers/erase_iter_iter_db1.pass.cpp
index 5553221c1679e3b8aea3c664d359b613d0127963..971f2bd3f5951c7dfdfac20e31758f4c07a869ff 100644
--- a/libcxx/test/libcxx/containers/sequences/list/list.modifiers/erase_iter_iter_db1.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/list/list.modifiers/erase_iter_iter_db1.pass.cpp
@@ -20,12 +20,14 @@
 #include <cassert>
 #include <cstdlib>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {1, 2, 3};
     std::list<int> l1(a1, a1+3);
     std::list<int> l2(a1, a1+3);
     std::list<int>::iterator i = l1.erase(l2.cbegin(), next(l1.cbegin()));
     assert(false);
+
+  return 0;
 }
 
diff --git a/libcxx/test/libcxx/containers/sequences/list/list.modifiers/erase_iter_iter_db2.pass.cpp b/libcxx/test/libcxx/containers/sequences/list/list.modifiers/erase_iter_iter_db2.pass.cpp
index 4ebe93b94bd2ec14cc6c2c6548af41966856b7e3..131529e5c7d7132cfe5a6e32464532139df526be 100644
--- a/libcxx/test/libcxx/containers/sequences/list/list.modifiers/erase_iter_iter_db2.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/list/list.modifiers/erase_iter_iter_db2.pass.cpp
@@ -20,11 +20,13 @@
 #include <cassert>
 #include <cstdlib>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {1, 2, 3};
     std::list<int> l1(a1, a1+3);
     std::list<int> l2(a1, a1+3);
     std::list<int>::iterator i = l1.erase(l1.cbegin(), next(l2.cbegin()));
     assert(false);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/list/list.modifiers/erase_iter_iter_db3.pass.cpp b/libcxx/test/libcxx/containers/sequences/list/list.modifiers/erase_iter_iter_db3.pass.cpp
index a89ee564569b042fccd9238a654de2b8873c0356..a9a35056ae7c7fa0e19f67bdd761be1638633b02 100644
--- a/libcxx/test/libcxx/containers/sequences/list/list.modifiers/erase_iter_iter_db3.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/list/list.modifiers/erase_iter_iter_db3.pass.cpp
@@ -20,11 +20,13 @@
 #include <cassert>
 #include <cstdlib>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {1, 2, 3};
     std::list<int> l1(a1, a1+3);
     std::list<int> l2(a1, a1+3);
     std::list<int>::iterator i = l1.erase(l2.cbegin(), next(l2.cbegin()));
     assert(false);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/list/list.modifiers/erase_iter_iter_db4.pass.cpp b/libcxx/test/libcxx/containers/sequences/list/list.modifiers/erase_iter_iter_db4.pass.cpp
index 60f9cf2e5221e3bf95cbadb2302504b89f777c84..642ee4498f5cecaf6d9743d442cef45b14bb40ba 100644
--- a/libcxx/test/libcxx/containers/sequences/list/list.modifiers/erase_iter_iter_db4.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/list/list.modifiers/erase_iter_iter_db4.pass.cpp
@@ -20,10 +20,12 @@
 #include <cassert>
 #include <cstdlib>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {1, 2, 3};
     std::list<int> l1(a1, a1+3);
     std::list<int>::iterator i = l1.erase(next(l1.cbegin()), l1.cbegin());
     assert(false);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/list/list.modifiers/insert_iter_iter_iter_db1.pass.cpp b/libcxx/test/libcxx/containers/sequences/list/list.modifiers/insert_iter_iter_iter_db1.pass.cpp
index d3370b5de440b1675c98a29e7636ead59488af7f..c7c7f76b9e2f7589f5caadf2662ecd666ee7e55f 100644
--- a/libcxx/test/libcxx/containers/sequences/list/list.modifiers/insert_iter_iter_iter_db1.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/list/list.modifiers/insert_iter_iter_iter_db1.pass.cpp
@@ -23,7 +23,7 @@
 #include <cassert>
 #include "test_iterators.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::list<int> v(100);
@@ -35,4 +35,6 @@ int main()
                                        input_iterator<const int*>(a+N));
         assert(false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/list/list.modifiers/insert_iter_rvalue_db1.pass.cpp b/libcxx/test/libcxx/containers/sequences/list/list.modifiers/insert_iter_rvalue_db1.pass.cpp
index d51658473738d048b359834f7816c2ecdb33d8b9..10503bd9cd719b30a29ddff06a2edb952719786a 100644
--- a/libcxx/test/libcxx/containers/sequences/list/list.modifiers/insert_iter_rvalue_db1.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/list/list.modifiers/insert_iter_rvalue_db1.pass.cpp
@@ -20,10 +20,12 @@
 #include <cstdlib>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::list<int> v1(3);
     std::list<int> v2(3);
     v1.insert(v2.begin(), 4);
     assert(false);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/list/list.modifiers/insert_iter_size_value_db1.pass.cpp b/libcxx/test/libcxx/containers/sequences/list/list.modifiers/insert_iter_size_value_db1.pass.cpp
index 5bd20f7b6f9364fda75fccfcf9eab53fc09d1d97..7a658e3942de8c4baaaffbd8d2fc070d71961ce3 100644
--- a/libcxx/test/libcxx/containers/sequences/list/list.modifiers/insert_iter_size_value_db1.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/list/list.modifiers/insert_iter_size_value_db1.pass.cpp
@@ -20,10 +20,12 @@
 #include <cstdlib>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::list<int> c1(100);
     std::list<int> c2;
     std::list<int>::iterator i = c1.insert(next(c2.cbegin(), 10), 5, 1);
     assert(false);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/list/list.modifiers/insert_iter_value_db1.pass.cpp b/libcxx/test/libcxx/containers/sequences/list/list.modifiers/insert_iter_value_db1.pass.cpp
index 17442509168862991fb95d1960a0be65afac0814..cdf01fe9079f2c55458266c5216ced95ce715b25 100644
--- a/libcxx/test/libcxx/containers/sequences/list/list.modifiers/insert_iter_value_db1.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/list/list.modifiers/insert_iter_value_db1.pass.cpp
@@ -21,11 +21,13 @@
 #include <cassert>
 
 
-int main()
+int main(int, char**)
 {
     std::list<int> v1(3);
     std::list<int> v2(3);
     int i = 4;
     v1.insert(v2.begin(), i);
     assert(false);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/list/list.modifiers/pop_back_db1.pass.cpp b/libcxx/test/libcxx/containers/sequences/list/list.modifiers/pop_back_db1.pass.cpp
index 4a292ff1f49e87294841afa766cfb2fceee7da57..8649f12a88790bccb19bde10ef45cba3cfa88055 100644
--- a/libcxx/test/libcxx/containers/sequences/list/list.modifiers/pop_back_db1.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/list/list.modifiers/pop_back_db1.pass.cpp
@@ -20,7 +20,7 @@
 #include <cstdlib>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a[] = {1, 2, 3};
     std::list<int> c(a, a+3);
@@ -32,4 +32,6 @@ int main()
     assert(c.empty());
     c.pop_back(); // operation under test
     assert(false);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/list/list.ops/db_splice_pos_list.pass.cpp b/libcxx/test/libcxx/containers/sequences/list/list.ops/db_splice_pos_list.pass.cpp
index 71882fd1476e424f6823070d515923462df04e99..23323d8c6fb756d40474dc830a016ee08eae5b21 100644
--- a/libcxx/test/libcxx/containers/sequences/list/list.ops/db_splice_pos_list.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/list/list.ops/db_splice_pos_list.pass.cpp
@@ -20,7 +20,7 @@
 #include <cstdlib>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::list<int> v1(3);
@@ -28,4 +28,6 @@ int main()
         v1.splice(v2.begin(), v2);
         assert(false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/list/list.ops/db_splice_pos_list_iter.pass.cpp b/libcxx/test/libcxx/containers/sequences/list/list.ops/db_splice_pos_list_iter.pass.cpp
index cfaf10b51eeff8fbad45cec8dd2566e96f13fb3b..37a206d2c97cae0d04b6588f0193edff2d2e0ae5 100644
--- a/libcxx/test/libcxx/containers/sequences/list/list.ops/db_splice_pos_list_iter.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/list/list.ops/db_splice_pos_list_iter.pass.cpp
@@ -20,7 +20,7 @@
 #include <cstdlib>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::list<int> v1(3);
@@ -28,4 +28,6 @@ int main()
         v1.splice(v1.begin(), v2, v1.begin());
         assert(false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/list/list.ops/db_splice_pos_list_iter_iter.pass.cpp b/libcxx/test/libcxx/containers/sequences/list/list.ops/db_splice_pos_list_iter_iter.pass.cpp
index 9f48a70898342cb34ba5dde24a31ab5bf21a0556..768c3d6f12200bc6bd0887b2469f92c570389d23 100644
--- a/libcxx/test/libcxx/containers/sequences/list/list.ops/db_splice_pos_list_iter_iter.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/list/list.ops/db_splice_pos_list_iter_iter.pass.cpp
@@ -20,7 +20,7 @@
 #include <cstdlib>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::list<int> v1(3);
@@ -28,4 +28,6 @@ int main()
         v1.splice(v1.begin(), v2, v2.begin(), v1.end());
         assert(false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/list/version.pass.cpp b/libcxx/test/libcxx/containers/sequences/list/version.pass.cpp
index 92a1988cfc7ff73f0848b0fa67c05234a4f29ffa..677c085b41f65902e108c78f37a7ba93e01822ab 100644
--- a/libcxx/test/libcxx/containers/sequences/list/version.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/list/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/vector/asan.pass.cpp b/libcxx/test/libcxx/containers/sequences/vector/asan.pass.cpp
index bf29d9b1460803ce8e35a94e2ff3c9068238e6c9..866cce152546de2728b34f36a78bffc5ee279478 100644
--- a/libcxx/test/libcxx/containers/sequences/vector/asan.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/vector/asan.pass.cpp
@@ -28,7 +28,7 @@ void do_exit() {
   exit(0);
 }
 
-int main()
+int main(int, char**)
 {
 #if TEST_STD_VER >= 11
     {
@@ -68,5 +68,5 @@ int main()
     }
 }
 #else
-int main () { return 0; }
+int main(int, char**) { return 0; }
 #endif
diff --git a/libcxx/test/libcxx/containers/sequences/vector/asan_throw.pass.cpp b/libcxx/test/libcxx/containers/sequences/vector/asan_throw.pass.cpp
index ce07bf77820dba0ed8540f62d1b68c3b8fe15cd8..443a6f2e924361567cabf3637a3fac26325236b4 100644
--- a/libcxx/test/libcxx/containers/sequences/vector/asan_throw.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/vector/asan_throw.pass.cpp
@@ -219,7 +219,7 @@ void test_resize_param() {
   assert(is_contiguous_container_asan_correct(v));
 }
 
-int main() {
+int main(int, char**) {
   test_push_back();
   test_emplace_back();
   test_insert_range();
@@ -230,4 +230,6 @@ int main() {
   test_insert_n2();
   test_resize();
   test_resize_param();
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/vector/const_value_type.pass.cpp b/libcxx/test/libcxx/containers/sequences/vector/const_value_type.pass.cpp
index ffe8ca4cae5e050641a1bef1af9941ee8bc9020c..d3407e3aa8b16ab8f2e05b196f842b8c2ab57064 100644
--- a/libcxx/test/libcxx/containers/sequences/vector/const_value_type.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/vector/const_value_type.pass.cpp
@@ -15,7 +15,9 @@
 #include <vector>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     std::vector<const int> v = {1, 2, 3};
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/vector/db_back.pass.cpp b/libcxx/test/libcxx/containers/sequences/vector/db_back.pass.cpp
index 21f19a9ecaecef7d7780980e67257a6fafeed7cc..3a35a086b636caef30c9b461078e36acdb1cf4c9 100644
--- a/libcxx/test/libcxx/containers/sequences/vector/db_back.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/vector/db_back.pass.cpp
@@ -23,7 +23,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int T;
@@ -49,8 +49,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/libcxx/containers/sequences/vector/db_cback.pass.cpp b/libcxx/test/libcxx/containers/sequences/vector/db_cback.pass.cpp
index cc1a3d2538911e7c5d6083062df7268d80f3b182..1c516ba57d9603b1b7afc76d6187c21210b0edbd 100644
--- a/libcxx/test/libcxx/containers/sequences/vector/db_cback.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/vector/db_cback.pass.cpp
@@ -23,7 +23,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int T;
@@ -45,8 +45,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/libcxx/containers/sequences/vector/db_cfront.pass.cpp b/libcxx/test/libcxx/containers/sequences/vector/db_cfront.pass.cpp
index 83d9c00b2dc3929a7b1d25f595f285b4b9fe475a..1dc7211f20845526b08c8f9836c662590aeb2287 100644
--- a/libcxx/test/libcxx/containers/sequences/vector/db_cfront.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/vector/db_cfront.pass.cpp
@@ -23,7 +23,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int T;
@@ -45,8 +45,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/libcxx/containers/sequences/vector/db_cindex.pass.cpp b/libcxx/test/libcxx/containers/sequences/vector/db_cindex.pass.cpp
index fc808eeb99ec4607c8bf07d4491cc5da60d39994..ceab50a86b9a0f28168b536f5d1f4af924c9f04a 100644
--- a/libcxx/test/libcxx/containers/sequences/vector/db_cindex.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/vector/db_cindex.pass.cpp
@@ -23,7 +23,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int T;
@@ -47,8 +47,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/libcxx/containers/sequences/vector/db_front.pass.cpp b/libcxx/test/libcxx/containers/sequences/vector/db_front.pass.cpp
index df7bd35e061ffcc7f512e639287480308c285a5e..a4aafcaefb7ee7de166ca8373bfef3f88dcdd0f6 100644
--- a/libcxx/test/libcxx/containers/sequences/vector/db_front.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/vector/db_front.pass.cpp
@@ -23,7 +23,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int T;
@@ -49,8 +49,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/libcxx/containers/sequences/vector/db_index.pass.cpp b/libcxx/test/libcxx/containers/sequences/vector/db_index.pass.cpp
index 5cb19254865dfd5e0540f589c72a68fc9089dfbf..a17ba274211005dda26671034687b65f53261a2e 100644
--- a/libcxx/test/libcxx/containers/sequences/vector/db_index.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/vector/db_index.pass.cpp
@@ -23,7 +23,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int T;
@@ -49,8 +49,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/libcxx/containers/sequences/vector/db_iterators_2.pass.cpp b/libcxx/test/libcxx/containers/sequences/vector/db_iterators_2.pass.cpp
index d7222dd184d28fd45a7c592edbbda6d6b586673c..975b5e951158ef8ba6b6e4f167a005899806ce88 100644
--- a/libcxx/test/libcxx/containers/sequences/vector/db_iterators_2.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/vector/db_iterators_2.pass.cpp
@@ -23,7 +23,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int T;
@@ -47,8 +47,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/libcxx/containers/sequences/vector/db_iterators_3.pass.cpp b/libcxx/test/libcxx/containers/sequences/vector/db_iterators_3.pass.cpp
index d39d99c3c3a7b189b294dcc346ab03f7ab11c3eb..0dcd6e7f240aef1c8545a097cf58cbadd7c1afef 100644
--- a/libcxx/test/libcxx/containers/sequences/vector/db_iterators_3.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/vector/db_iterators_3.pass.cpp
@@ -23,7 +23,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int T;
@@ -47,8 +47,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/libcxx/containers/sequences/vector/db_iterators_4.pass.cpp b/libcxx/test/libcxx/containers/sequences/vector/db_iterators_4.pass.cpp
index f868b755eb89a1f5df2dd402ae77597b01895265..8d048f2fd2781c671af20d2e1560c014dde34afe 100644
--- a/libcxx/test/libcxx/containers/sequences/vector/db_iterators_4.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/vector/db_iterators_4.pass.cpp
@@ -23,7 +23,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int T;
@@ -49,8 +49,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/libcxx/containers/sequences/vector/db_iterators_5.pass.cpp b/libcxx/test/libcxx/containers/sequences/vector/db_iterators_5.pass.cpp
index c5039f9f8abcacd88d5386981f215f08a71bd38b..19060da3d1a84acb0aad2a4489466c53f503f97a 100644
--- a/libcxx/test/libcxx/containers/sequences/vector/db_iterators_5.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/vector/db_iterators_5.pass.cpp
@@ -23,7 +23,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int T;
@@ -53,8 +53,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/libcxx/containers/sequences/vector/db_iterators_6.pass.cpp b/libcxx/test/libcxx/containers/sequences/vector/db_iterators_6.pass.cpp
index ff60a05a4aea9349ba6150bc0efab36fbbc4c0da..13156c22fe38bab46aa1ca9b57684e69177948e0 100644
--- a/libcxx/test/libcxx/containers/sequences/vector/db_iterators_6.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/vector/db_iterators_6.pass.cpp
@@ -23,7 +23,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int T;
@@ -51,8 +51,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/libcxx/containers/sequences/vector/db_iterators_7.pass.cpp b/libcxx/test/libcxx/containers/sequences/vector/db_iterators_7.pass.cpp
index 8249fd752522950185281cfa995ce99ac0d9bde6..943c5209b0d51a366a291e3d5973c1bb6d84e6a5 100644
--- a/libcxx/test/libcxx/containers/sequences/vector/db_iterators_7.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/vector/db_iterators_7.pass.cpp
@@ -23,7 +23,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int T;
@@ -51,8 +51,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/libcxx/containers/sequences/vector/db_iterators_8.pass.cpp b/libcxx/test/libcxx/containers/sequences/vector/db_iterators_8.pass.cpp
index c619f20dd6df829b428de1df838aded06906ddb2..39f26f66801afdb9c57956bbc48d459f8191fccf 100644
--- a/libcxx/test/libcxx/containers/sequences/vector/db_iterators_8.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/vector/db_iterators_8.pass.cpp
@@ -23,7 +23,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int T;
@@ -47,8 +47,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/libcxx/containers/sequences/vector/pop_back_empty.pass.cpp b/libcxx/test/libcxx/containers/sequences/vector/pop_back_empty.pass.cpp
index 0ce185325957a832fbc94d95aa668571a83747d4..1d1e3a1ba3d9acefacffd6b2528f6c318ef388a7 100644
--- a/libcxx/test/libcxx/containers/sequences/vector/pop_back_empty.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/vector/pop_back_empty.pass.cpp
@@ -16,10 +16,12 @@
 #include <vector>
 
 
-int main() {
+int main(int, char**) {
     std::vector<int> v;
     v.push_back(0);
     v.pop_back();
     v.pop_back();
     std::exit(1);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/vector/vector.cons/construct_iter_iter.pass.cpp b/libcxx/test/libcxx/containers/sequences/vector/vector.cons/construct_iter_iter.pass.cpp
index ee139c18894c7c02b7a12ea6572b3c2a8bc5dfcb..81263dec0bda4d4535604c38f7231b040966eb4d 100644
--- a/libcxx/test/libcxx/containers/sequences/vector/vector.cons/construct_iter_iter.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/vector/vector.cons/construct_iter_iter.pass.cpp
@@ -48,6 +48,8 @@ void test_ctor_under_alloc() {
   }
 }
 
-int main() {
+int main(int, char**) {
   test_ctor_under_alloc();
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/vector/vector.cons/construct_iter_iter_alloc.pass.cpp b/libcxx/test/libcxx/containers/sequences/vector/vector.cons/construct_iter_iter_alloc.pass.cpp
index 37814b2f13a34fb379b67f7b5d3865c7857bfca2..0100507eab04111a6023286be63896991dd571c3 100644
--- a/libcxx/test/libcxx/containers/sequences/vector/vector.cons/construct_iter_iter_alloc.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/vector/vector.cons/construct_iter_iter_alloc.pass.cpp
@@ -51,6 +51,8 @@ void test_ctor_under_alloc() {
   }
 }
 
-int main() {
+int main(int, char**) {
   test_ctor_under_alloc();
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/sequences/vector/version.pass.cpp b/libcxx/test/libcxx/containers/sequences/vector/version.pass.cpp
index 16f45fc0b900feffd32ee5e4df5fec3dbb573b33..93fd2e679b5446bd16d9e00e67fb5a15f95bbd98 100644
--- a/libcxx/test/libcxx/containers/sequences/vector/version.pass.cpp
+++ b/libcxx/test/libcxx/containers/sequences/vector/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/unord/key_value_traits.pass.cpp b/libcxx/test/libcxx/containers/unord/key_value_traits.pass.cpp
index c2d754b119acd67c7f2433401de7ba915569a13a..c5e420387fdaf4a688e0f9d40683dd958f0a38fd 100644
--- a/libcxx/test/libcxx/containers/unord/key_value_traits.pass.cpp
+++ b/libcxx/test/libcxx/containers/unord/key_value_traits.pass.cpp
@@ -53,6 +53,8 @@ void testKeyValueTrait() {
   }
 }
 
-int main() {
+int main(int, char**) {
   testKeyValueTrait();
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/unord/next_pow2.pass.cpp b/libcxx/test/libcxx/containers/unord/next_pow2.pass.cpp
index 36229dc2409681a68eb092737f13c49fe26278df..2b4d02eec38a4e304949a7f1f7964258b5cb5ab1 100644
--- a/libcxx/test/libcxx/containers/unord/next_pow2.pass.cpp
+++ b/libcxx/test/libcxx/containers/unord/next_pow2.pass.cpp
@@ -74,7 +74,7 @@ fuzz_unordered_map_reserve(unsigned num_inserts,
     assert(m.bucket_count() >= num_reserve2);
 }
 
-int main()
+int main(int, char**)
 {
     test_next_pow2();
 
diff --git a/libcxx/test/libcxx/containers/unord/next_prime.pass.cpp b/libcxx/test/libcxx/containers/unord/next_prime.pass.cpp
index e049e451a565e2e0cad5a6e618ad9e2cdc0887af..6a82ea1d6b222a16b43dab37bff38e09368865a3 100644
--- a/libcxx/test/libcxx/containers/unord/next_prime.pass.cpp
+++ b/libcxx/test/libcxx/containers/unord/next_prime.pass.cpp
@@ -36,7 +36,7 @@ is_prime(size_t n)
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     assert(std::__next_prime(0) == 0);
     for (std::size_t n = 1; n <= 100000; ++n)
@@ -47,4 +47,6 @@ int main()
             assert(!is_prime(i));
         assert(is_prime(p));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/unord/non_const_comparator.fail.cpp b/libcxx/test/libcxx/containers/unord/non_const_comparator.fail.cpp
index 15fb8d4eda1b0896a8d77267e5b8e44b2d8ce3b9..8fa500e45e444a95b769d945ff20f01ca9bda271 100644
--- a/libcxx/test/libcxx/containers/unord/non_const_comparator.fail.cpp
+++ b/libcxx/test/libcxx/containers/unord/non_const_comparator.fail.cpp
@@ -29,7 +29,7 @@ struct BadEqual {
   }
 };
 
-int main() {
+int main(int, char**) {
   static_assert(!std::__invokable<BadEqual const&, int const&, int const&>::value, "");
   static_assert(std::__invokable<BadEqual&, int const&, int const&>::value, "");
 
@@ -54,4 +54,6 @@ int main() {
     using C = std::unordered_multimap<long, int, BadHash, BadEqual>;
     C s;
   }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/unord/unord.map/db_iterators_7.pass.cpp b/libcxx/test/libcxx/containers/unord/unord.map/db_iterators_7.pass.cpp
index 0206b998c66fe290b24e2454a754a34ba788b8a4..9ff6bafc3adefb293d3db913cc9488cd26b08053 100644
--- a/libcxx/test/libcxx/containers/unord/unord.map/db_iterators_7.pass.cpp
+++ b/libcxx/test/libcxx/containers/unord/unord.map/db_iterators_7.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::unordered_map<int, std::string> C;
@@ -53,8 +53,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/libcxx/containers/unord/unord.map/db_iterators_8.pass.cpp b/libcxx/test/libcxx/containers/unord/unord.map/db_iterators_8.pass.cpp
index 79ddccd1f57e0769a8bdc08b02a0f6a46f771a72..ef383aa9f5d976bffa2f8866c4d9c7a3fcedc4f7 100644
--- a/libcxx/test/libcxx/containers/unord/unord.map/db_iterators_8.pass.cpp
+++ b/libcxx/test/libcxx/containers/unord/unord.map/db_iterators_8.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::unordered_map<int, std::string> C;
@@ -49,8 +49,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/libcxx/containers/unord/unord.map/db_local_iterators_7.pass.cpp b/libcxx/test/libcxx/containers/unord/unord.map/db_local_iterators_7.pass.cpp
index 002dcd31a980af5260dbacab9bee7c70bceaf737..5c2b4024ae9a7118fea3ca4458c82acd75870069 100644
--- a/libcxx/test/libcxx/containers/unord/unord.map/db_local_iterators_7.pass.cpp
+++ b/libcxx/test/libcxx/containers/unord/unord.map/db_local_iterators_7.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::unordered_map<int, std::string> C;
@@ -50,8 +50,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/libcxx/containers/unord/unord.map/db_local_iterators_8.pass.cpp b/libcxx/test/libcxx/containers/unord/unord.map/db_local_iterators_8.pass.cpp
index 887093b3c4b70e57d22a83300e258f24a923fb87..8e76f1bda459cbc2ad14e45129d430edfacf670e 100644
--- a/libcxx/test/libcxx/containers/unord/unord.map/db_local_iterators_8.pass.cpp
+++ b/libcxx/test/libcxx/containers/unord/unord.map/db_local_iterators_8.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::unordered_map<int, std::string> C;
@@ -47,8 +47,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/libcxx/containers/unord/unord.map/version.pass.cpp b/libcxx/test/libcxx/containers/unord/unord.map/version.pass.cpp
index ce4a2784c61879cf14643d902b8a1fd3cc7564b5..983acde548b8f62df1f99617171a1b3a5ff6755d 100644
--- a/libcxx/test/libcxx/containers/unord/unord.map/version.pass.cpp
+++ b/libcxx/test/libcxx/containers/unord/unord.map/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/unord/unord.set/missing_hash_specialization.fail.cpp b/libcxx/test/libcxx/containers/unord/unord.set/missing_hash_specialization.fail.cpp
index 9ef240df80feacbdf50579ea3e624d00eb304546..af94748fdd92499dc48bc75c9c29d49074d9e76e 100644
--- a/libcxx/test/libcxx/containers/unord/unord.set/missing_hash_specialization.fail.cpp
+++ b/libcxx/test/libcxx/containers/unord/unord.set/missing_hash_specialization.fail.cpp
@@ -42,7 +42,7 @@ struct GoodHashNoDefault {
   size_t operator()(T const&) const { return 0; }
 };
 
-int main() {
+int main(int, char**) {
 
   {
     using Set = std::unordered_set<VT>;
@@ -66,4 +66,6 @@ int main() {
     using Set = std::unordered_set<int, GoodHashNoDefault>;
     Set s(/*bucketcount*/42, GoodHashNoDefault(nullptr));
   }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/containers/unord/unord.set/version.pass.cpp b/libcxx/test/libcxx/containers/unord/unord.set/version.pass.cpp
index 477867757d07e6563239d5cadd23d7256cc1e075..63144528cf930f5255801ff867488328afb2accf 100644
--- a/libcxx/test/libcxx/containers/unord/unord.set/version.pass.cpp
+++ b/libcxx/test/libcxx/containers/unord/unord.set/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/debug/containers/db_associative_container_tests.pass.cpp b/libcxx/test/libcxx/debug/containers/db_associative_container_tests.pass.cpp
index e78e4ec7606773236271ee228d32df5610f94797..d6c231527dda248f039afaee70b3eb04de04c06a 100644
--- a/libcxx/test/libcxx/debug/containers/db_associative_container_tests.pass.cpp
+++ b/libcxx/test/libcxx/debug/containers/db_associative_container_tests.pass.cpp
@@ -51,7 +51,7 @@ private:
   // FIXME Add tests here
 };
 
-int main()
+int main(int, char**)
 {
   using SetAlloc = test_allocator<int>;
   using MapAlloc = test_allocator<std::pair<const int, int>>;
@@ -66,4 +66,6 @@ int main()
     AssociativeContainerChecks<
         std::multimap<int, int, std::less<int>, MapAlloc>, CT_MultiMap>::run();
   }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/debug/containers/db_sequence_container_iterators.pass.cpp b/libcxx/test/libcxx/debug/containers/db_sequence_container_iterators.pass.cpp
index 94ad45b48b17be1f14d706432d9868bd5d839fdf..d05f9df3b98b960d6410af1de0681eaed787f98d 100644
--- a/libcxx/test/libcxx/debug/containers/db_sequence_container_iterators.pass.cpp
+++ b/libcxx/test/libcxx/debug/containers/db_sequence_container_iterators.pass.cpp
@@ -307,7 +307,7 @@ private:
   }
 };
 
-int main()
+int main(int, char**)
 {
   using Alloc = test_allocator<int>;
   {
@@ -323,4 +323,6 @@ int main()
     SequenceContainerChecks<
         std::deque<int, Alloc>, CT_Deque>::run();
   }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/debug/containers/db_string.pass.cpp b/libcxx/test/libcxx/debug/containers/db_string.pass.cpp
index e3b2b290dd672cc35542cbdf1ab22f98cdf70d12..b2812fca619677d3f04bbdab3997e62510080d17 100644
--- a/libcxx/test/libcxx/debug/containers/db_string.pass.cpp
+++ b/libcxx/test/libcxx/debug/containers/db_string.pass.cpp
@@ -93,7 +93,9 @@ private:
   }
 };
 
-int main()
+int main(int, char**)
 {
   StringContainerChecks<>::run();
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/debug/containers/db_unord_container_tests.pass.cpp b/libcxx/test/libcxx/debug/containers/db_unord_container_tests.pass.cpp
index 069c4ae21a67de7a725ca6f45e1b5379994b1da1..8a6da08263bf19f0b5f47e7724a972311a5de482 100644
--- a/libcxx/test/libcxx/debug/containers/db_unord_container_tests.pass.cpp
+++ b/libcxx/test/libcxx/debug/containers/db_unord_container_tests.pass.cpp
@@ -49,7 +49,7 @@ private:
 
 };
 
-int main()
+int main(int, char**)
 {
   using SetAlloc = test_allocator<int>;
   using MapAlloc = test_allocator<std::pair<const int, int>>;
@@ -67,4 +67,6 @@ int main()
         std::unordered_multiset<int, std::hash<int>, std::equal_to<int>, SetAlloc>,
         CT_UnorderedMultiSet>::run();
   }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/debug/debug_abort.pass.cpp b/libcxx/test/libcxx/debug/debug_abort.pass.cpp
index a9dae6eeae76c64a0328c294717cbca4c810bb2c..270f2cb0f43b1a26b103cc257ebaf729daf81b1a 100644
--- a/libcxx/test/libcxx/debug/debug_abort.pass.cpp
+++ b/libcxx/test/libcxx/debug/debug_abort.pass.cpp
@@ -27,7 +27,7 @@ void signal_handler(int signal)
     std::_Exit(EXIT_FAILURE);
 }
 
-int main()
+int main(int, char**)
 {
   if (std::signal(SIGABRT, signal_handler) != SIG_ERR)
     _LIBCPP_ASSERT(false, "foo");
diff --git a/libcxx/test/libcxx/debug/debug_throw.pass.cpp b/libcxx/test/libcxx/debug/debug_throw.pass.cpp
index c17546ebd285d89a3804aa988b838fa11b895e38..53e8538c4a6bd2e5516dc5eb672986374bfd7d91 100644
--- a/libcxx/test/libcxx/debug/debug_throw.pass.cpp
+++ b/libcxx/test/libcxx/debug/debug_throw.pass.cpp
@@ -23,7 +23,7 @@
 #include <type_traits>
 #include <__debug>
 
-int main()
+int main(int, char**)
 {
   {
     std::__libcpp_debug_function = std::__libcpp_throw_debug_function;
@@ -37,4 +37,6 @@ int main()
                                   std::__libcpp_debug_exception
                   >::value), "must be an exception");
   }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/debug/debug_throw_register.pass.cpp b/libcxx/test/libcxx/debug/debug_throw_register.pass.cpp
index 6d345f0ba0fb4957fcc9682febd37800ac5aa596..23b4091c3a0cbb25aab43210f78a240ad2f4cec0 100644
--- a/libcxx/test/libcxx/debug/debug_throw_register.pass.cpp
+++ b/libcxx/test/libcxx/debug/debug_throw_register.pass.cpp
@@ -26,10 +26,12 @@
 #include <__debug>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
   try {
     _LIBCPP_ASSERT(false, "foo");
     assert(false);
   } catch (...) {}
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/depr/depr.auto.ptr/auto.ptr/auto_ptr.cxx1z.pass.cpp b/libcxx/test/libcxx/depr/depr.auto.ptr/auto.ptr/auto_ptr.cxx1z.pass.cpp
index 3b387b3aba2bad60f2b2f0b57c4b03793b5932ff..7f59ca20241e244c5bd11b0e310da4a3d18395a1 100644
--- a/libcxx/test/libcxx/depr/depr.auto.ptr/auto.ptr/auto_ptr.cxx1z.pass.cpp
+++ b/libcxx/test/libcxx/depr/depr.auto.ptr/auto.ptr/auto_ptr.cxx1z.pass.cpp
@@ -22,7 +22,9 @@
 #include <memory>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     std::auto_ptr<int> p;
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/depr/depr.auto.ptr/auto.ptr/auto_ptr.depr_in_cxx11.fail.cpp b/libcxx/test/libcxx/depr/depr.auto.ptr/auto.ptr/auto_ptr.depr_in_cxx11.fail.cpp
index be0ce6617dddb494d2d3bb66952d49c444feac9a..db4ac4aae02c5ea615d4bb8cfbfbb66ca658425c 100644
--- a/libcxx/test/libcxx/depr/depr.auto.ptr/auto.ptr/auto_ptr.depr_in_cxx11.fail.cpp
+++ b/libcxx/test/libcxx/depr/depr.auto.ptr/auto.ptr/auto_ptr.depr_in_cxx11.fail.cpp
@@ -30,9 +30,11 @@
 #include <memory>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::auto_ptr<int> AP; // expected-error{{'auto_ptr<int>' is deprecated}}
     typedef std::auto_ptr<void> APV; // expected-error{{'auto_ptr<void>' is deprecated}}
     typedef std::auto_ptr_ref<int> APR; // expected-error{{'auto_ptr_ref<int>' is deprecated}}
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/depr/depr.c.headers/ciso646.pass.cpp b/libcxx/test/libcxx/depr/depr.c.headers/ciso646.pass.cpp
index 4009a5ce25e8fcfede1a02a26234694346e304df..7a83994140d92470980bcc1675d2b51d5e35f645 100644
--- a/libcxx/test/libcxx/depr/depr.c.headers/ciso646.pass.cpp
+++ b/libcxx/test/libcxx/depr/depr.c.headers/ciso646.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/depr/depr.c.headers/complex.h.pass.cpp b/libcxx/test/libcxx/depr/depr.c.headers/complex.h.pass.cpp
index 4f035e014675fd0b14fcca1275f9d206553cf3c4..07529aef261d449a8e77eaf492c02ec21f881739 100644
--- a/libcxx/test/libcxx/depr/depr.c.headers/complex.h.pass.cpp
+++ b/libcxx/test/libcxx/depr/depr.c.headers/complex.h.pass.cpp
@@ -14,8 +14,10 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
     std::complex<double> d;
     (void)d;
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/depr/depr.c.headers/extern_c.pass.cpp b/libcxx/test/libcxx/depr/depr.c.headers/extern_c.pass.cpp
index 5b036ab41897de375d69fa6fb11a5b3fc0f2fd8e..24a104f5edd43206406cf967220cc8420b3ad159 100644
--- a/libcxx/test/libcxx/depr/depr.c.headers/extern_c.pass.cpp
+++ b/libcxx/test/libcxx/depr/depr.c.headers/extern_c.pass.cpp
@@ -39,4 +39,6 @@ extern "C" {
 #include <wctype.h>
 }
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/libcxx/depr/depr.c.headers/locale_h.pass.cpp b/libcxx/test/libcxx/depr/depr.c.headers/locale_h.pass.cpp
index 63f63ef5917676ea910e2c0093df428b81e688a9..ea117f6b27b33846ecf9ae575f2b20bd35e7d0b0 100644
--- a/libcxx/test/libcxx/depr/depr.c.headers/locale_h.pass.cpp
+++ b/libcxx/test/libcxx/depr/depr.c.headers/locale_h.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/depr/depr.c.headers/tgmath_h.pass.cpp b/libcxx/test/libcxx/depr/depr.c.headers/tgmath_h.pass.cpp
index 7252ab00a2cbe71ae4d88317801ddeaed0e9610a..835e2f21616abd17a269e3eeb90b0addc3fcf640 100644
--- a/libcxx/test/libcxx/depr/depr.c.headers/tgmath_h.pass.cpp
+++ b/libcxx/test/libcxx/depr/depr.c.headers/tgmath_h.pass.cpp
@@ -14,10 +14,12 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
     std::complex<double> cd;
     (void)cd;
     double x = sin(1.0);
     (void)x; // to placate scan-build
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/depr/depr.function.objects/adaptors.depr_in_cxx11.fail.cpp b/libcxx/test/libcxx/depr/depr.function.objects/adaptors.depr_in_cxx11.fail.cpp
index 489fc874eb09ca34abb1ef8baae87065e2dcfcdf..e26a7549883a9610cd1f1e30886a4c40b7b8a99d 100644
--- a/libcxx/test/libcxx/depr/depr.function.objects/adaptors.depr_in_cxx11.fail.cpp
+++ b/libcxx/test/libcxx/depr/depr.function.objects/adaptors.depr_in_cxx11.fail.cpp
@@ -31,7 +31,7 @@ struct Foo {
     int identity(int v) { return v; }
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::pointer_to_unary_function<int, int> PUF; // expected-error{{'pointer_to_unary_function<int, int>' is deprecated}}
     typedef std::pointer_to_binary_function<int, int, int> PBF; // expected-error{{'pointer_to_binary_function<int, int, int>' is deprecated}}
@@ -55,4 +55,6 @@ int main()
     std::mem_fun_ref<int, Foo, int>(&Foo::identity); // expected-error{{'mem_fun_ref<int, Foo, int>' is deprecated}}
     std::mem_fun_ref<int, Foo>(&Foo::const_zero); // expected-error{{'mem_fun_ref<int, Foo>' is deprecated}}
     std::mem_fun_ref<int, Foo, int>(&Foo::const_identity); // expected-error{{'mem_fun_ref<int, Foo, int>' is deprecated}}
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/depr/depr.function.objects/depr.adaptors.cxx1z.pass.cpp b/libcxx/test/libcxx/depr/depr.function.objects/depr.adaptors.cxx1z.pass.cpp
index 5ea5626285bbe62e8e2cbbf6c73092beb110a251..7b759d04bd92654a3fdc81d7a23dd9e3ef72f29b 100644
--- a/libcxx/test/libcxx/depr/depr.function.objects/depr.adaptors.cxx1z.pass.cpp
+++ b/libcxx/test/libcxx/depr/depr.function.objects/depr.adaptors.cxx1z.pass.cpp
@@ -30,7 +30,7 @@ struct Foo {
   int sum(int a, int b) const { return a + b; }
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::pointer_to_unary_function<int, int> PUF;
     typedef std::pointer_to_binary_function<int, int, int> PBF;
@@ -60,4 +60,6 @@ int main()
 
     assert((std::mem_fun_ref(&Foo::zero)(f) == 0));
     assert((std::mem_fun_ref(&Foo::identity)(f, 5) == 5));
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/depr/depr.str.strstreams/version.pass.cpp b/libcxx/test/libcxx/depr/depr.str.strstreams/version.pass.cpp
index 9d6b9762e73c091bb1bf1d81191b2741fd273dd3..148f233cee2c978a391a555b0d0e0516aef3b79a 100644
--- a/libcxx/test/libcxx/depr/depr.str.strstreams/version.pass.cpp
+++ b/libcxx/test/libcxx/depr/depr.str.strstreams/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/depr/enable_removed_cpp17_features.pass.cpp b/libcxx/test/libcxx/depr/enable_removed_cpp17_features.pass.cpp
index bd1ee604c70421e59e9cfcb2331c70fe69d88937..2065b2b4eeaf27e91fe9b92d0dcd4d78d225a4c5 100644
--- a/libcxx/test/libcxx/depr/enable_removed_cpp17_features.pass.cpp
+++ b/libcxx/test/libcxx/depr/enable_removed_cpp17_features.pass.cpp
@@ -21,5 +21,7 @@
 #error _LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR must be defined
 #endif
 
-int main() {
+int main(int, char**) {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/depr/exception.unexpected/get_unexpected.pass.cpp b/libcxx/test/libcxx/depr/exception.unexpected/get_unexpected.pass.cpp
index 4d49440fc63e00f34145977ca6f10afa0bf25639..ca14271f02dcc34ca26297bf11a47cfa02742c9c 100644
--- a/libcxx/test/libcxx/depr/exception.unexpected/get_unexpected.pass.cpp
+++ b/libcxx/test/libcxx/depr/exception.unexpected/get_unexpected.pass.cpp
@@ -23,7 +23,7 @@ void f3()
     std::exit(0);
 }
 
-int main()
+int main(int, char**)
 {
 
     std::unexpected_handler old = std::get_unexpected();
@@ -38,4 +38,6 @@ int main()
     std::set_terminate(f3);
     (*old)();
     assert(0);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/depr/exception.unexpected/set_unexpected.pass.cpp b/libcxx/test/libcxx/depr/exception.unexpected/set_unexpected.pass.cpp
index 43836f4fb9b5716824a40b078131150828e73cf1..dd861941a447b15112a5f3fb9f7d3d103cb81192 100644
--- a/libcxx/test/libcxx/depr/exception.unexpected/set_unexpected.pass.cpp
+++ b/libcxx/test/libcxx/depr/exception.unexpected/set_unexpected.pass.cpp
@@ -22,7 +22,7 @@ void f3()
     std::exit(0);
 }
 
-int main()
+int main(int, char**)
 {
     std::unexpected_handler old = std::set_unexpected(f1);
     // verify there is a previous unexpected handler
@@ -33,4 +33,6 @@ int main()
     std::set_terminate(f3);
     (*old)();
     assert(0);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/depr/exception.unexpected/unexpected.pass.cpp b/libcxx/test/libcxx/depr/exception.unexpected/unexpected.pass.cpp
index e4d85e1f2da34ca578c8ecec42b7937557cd00b4..b9bdabe0e76e96adc6e597a6a191a8027291e868 100644
--- a/libcxx/test/libcxx/depr/exception.unexpected/unexpected.pass.cpp
+++ b/libcxx/test/libcxx/depr/exception.unexpected/unexpected.pass.cpp
@@ -19,9 +19,11 @@ void fexit()
     std::exit(0);
 }
 
-int main()
+int main(int, char**)
 {
     std::set_unexpected(fexit);
     std::unexpected();
     assert(false);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/depr/exception.unexpected/unexpected_disabled_cpp17.fail.cpp b/libcxx/test/libcxx/depr/exception.unexpected/unexpected_disabled_cpp17.fail.cpp
index 6a8549128577ef31966899dea12e5a8650682995..0388cfaf7ad3a46fcbb7fa86ebbdeca0cc501d6a 100644
--- a/libcxx/test/libcxx/depr/exception.unexpected/unexpected_disabled_cpp17.fail.cpp
+++ b/libcxx/test/libcxx/depr/exception.unexpected/unexpected_disabled_cpp17.fail.cpp
@@ -14,9 +14,11 @@
 
 void f() {}
 
-int main() {
+int main(int, char**) {
   using T = std::unexpected_handler; // expected-error {{no type named 'unexpected_handler' in namespace 'std'}}
   std::unexpected(); // expected-error {{no member named 'unexpected' in namespace 'std'}}
   std::get_unexpected(); // expected-error {{no member named 'get_unexpected' in namespace 'std'}}
   std::set_unexpected(f); // expected-error {{no type named 'set_unexpected' in namespace 'std'}}
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/diagnostics/assertions/version_cassert.pass.cpp b/libcxx/test/libcxx/diagnostics/assertions/version_cassert.pass.cpp
index 374ed6fedac34178f983b49a6d6760aa4f4916d8..f2fb0952402e3bb1091347f48ffe923e32062175 100644
--- a/libcxx/test/libcxx/diagnostics/assertions/version_cassert.pass.cpp
+++ b/libcxx/test/libcxx/diagnostics/assertions/version_cassert.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/diagnostics/enable_nodiscard.fail.cpp b/libcxx/test/libcxx/diagnostics/enable_nodiscard.fail.cpp
index d756c3f9ea6c6a525339d23eab1bf1815613f876..0cd74be2f500e2202c862cf633c3d38204d536c3 100644
--- a/libcxx/test/libcxx/diagnostics/enable_nodiscard.fail.cpp
+++ b/libcxx/test/libcxx/diagnostics/enable_nodiscard.fail.cpp
@@ -24,9 +24,11 @@
 _LIBCPP_NODISCARD_EXT int foo() { return 42; }
 _LIBCPP_NODISCARD_AFTER_CXX17 int bar() { return 42; }
 
-int main() {
+int main(int, char**) {
   foo(); // expected-error-re {{ignoring return value of function declared with {{'nodiscard'|warn_unused_result}} attribute}}
   bar(); // expected-error-re {{ignoring return value of function declared with {{'nodiscard'|warn_unused_result}} attribute}}
   (void)foo(); // OK. void casts disable the diagnostic.
   (void)bar();
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/diagnostics/enable_nodiscard_disable_after_cxx17.fail.cpp b/libcxx/test/libcxx/diagnostics/enable_nodiscard_disable_after_cxx17.fail.cpp
index a7a81f53ff33b03f988255ca23d183300ad8a5c0..530ea54ca60880055a515c45e9c3da79c9accd60 100644
--- a/libcxx/test/libcxx/diagnostics/enable_nodiscard_disable_after_cxx17.fail.cpp
+++ b/libcxx/test/libcxx/diagnostics/enable_nodiscard_disable_after_cxx17.fail.cpp
@@ -25,8 +25,10 @@
 _LIBCPP_NODISCARD_EXT int foo() { return 42; }
 _LIBCPP_NODISCARD_AFTER_CXX17 int bar() { return 42; }
 
-int main() {
+int main(int, char**) {
   foo(); // expected-error-re {{ignoring return value of function declared with {{'nodiscard'|warn_unused_result}} attribute}}
   bar(); // OK.
   (void)foo(); // OK.
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/diagnostics/enable_nodiscard_disable_nodiscard_ext.fail.cpp b/libcxx/test/libcxx/diagnostics/enable_nodiscard_disable_nodiscard_ext.fail.cpp
index 65b3bbeabae47c834ff6281767e7096dfd48d5d2..56df9248da1ba5664f21c17bcc5d979cc3075279 100644
--- a/libcxx/test/libcxx/diagnostics/enable_nodiscard_disable_nodiscard_ext.fail.cpp
+++ b/libcxx/test/libcxx/diagnostics/enable_nodiscard_disable_nodiscard_ext.fail.cpp
@@ -23,8 +23,10 @@
 _LIBCPP_NODISCARD_EXT int foo() { return 42; }
 _LIBCPP_NODISCARD_AFTER_CXX17 int bar() { return 42; }
 
-int main() {
+int main(int, char**) {
   bar(); // expected-error-re {{ignoring return value of function declared with {{'nodiscard'|warn_unused_result}} attribute}}
   foo(); // OK.
   (void)bar(); // OK.
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/diagnostics/errno/version_cerrno.pass.cpp b/libcxx/test/libcxx/diagnostics/errno/version_cerrno.pass.cpp
index c47c75e8c8457e6e1fa34cce44ae7e6fc39c38c5..a8c51c01337fbc3906e787bf9b62e54ebba6e11a 100644
--- a/libcxx/test/libcxx/diagnostics/errno/version_cerrno.pass.cpp
+++ b/libcxx/test/libcxx/diagnostics/errno/version_cerrno.pass.cpp
@@ -15,4 +15,6 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/libcxx/diagnostics/nodiscard.pass.cpp b/libcxx/test/libcxx/diagnostics/nodiscard.pass.cpp
index 628ff57ee76120d58d56e965919230ee1b0da43b..1db9a67a8b309c10878f3de154fdbe734442438b 100644
--- a/libcxx/test/libcxx/diagnostics/nodiscard.pass.cpp
+++ b/libcxx/test/libcxx/diagnostics/nodiscard.pass.cpp
@@ -14,6 +14,8 @@
 
 _LIBCPP_NODISCARD_EXT int foo() { return 42; }
 
-int main() {
+int main(int, char**) {
   foo(); // OK.
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/diagnostics/nodiscard_aftercxx17.fail.cpp b/libcxx/test/libcxx/diagnostics/nodiscard_aftercxx17.fail.cpp
index 250f858be0136100ba5577b103312e3aadd21356..8cfbc3117853bdff69dddc64253f11165550dca4 100644
--- a/libcxx/test/libcxx/diagnostics/nodiscard_aftercxx17.fail.cpp
+++ b/libcxx/test/libcxx/diagnostics/nodiscard_aftercxx17.fail.cpp
@@ -16,7 +16,9 @@
 
 _LIBCPP_NODISCARD_AFTER_CXX17 int foo() { return 6; }
 
-int main ()
+int main(int, char**)
 {
 	foo();	// expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/diagnostics/nodiscard_aftercxx17.pass.cpp b/libcxx/test/libcxx/diagnostics/nodiscard_aftercxx17.pass.cpp
index 527487faa9705e20f86c09f4d33188a5c0bb3e57..959ba4854b871617e4f903e27fd13b7c22367141 100644
--- a/libcxx/test/libcxx/diagnostics/nodiscard_aftercxx17.pass.cpp
+++ b/libcxx/test/libcxx/diagnostics/nodiscard_aftercxx17.pass.cpp
@@ -16,7 +16,9 @@
 
 _LIBCPP_NODISCARD_AFTER_CXX17 int foo() { return 6; }
 
-int main ()
+int main(int, char**)
 {
 	foo();	// no error here!
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/diagnostics/nodiscard_extensions.fail.cpp b/libcxx/test/libcxx/diagnostics/nodiscard_extensions.fail.cpp
index 6fc95bbeb99f21f82dc13753d9c7b69e8bbe1408..a265e8755b566613406c7cfd6dd9e49d399ddf66 100644
--- a/libcxx/test/libcxx/diagnostics/nodiscard_extensions.fail.cpp
+++ b/libcxx/test/libcxx/diagnostics/nodiscard_extensions.fail.cpp
@@ -26,9 +26,11 @@
 
 #include "test_macros.h"
 
-int main() {
+int main(int, char**) {
   {
     // expected-error-re@+1 {{ignoring return value of function declared with {{'nodiscard'|warn_unused_result}} attribute}}
     std::get_temporary_buffer<int>(1);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/diagnostics/nodiscard_extensions.pass.cpp b/libcxx/test/libcxx/diagnostics/nodiscard_extensions.pass.cpp
index bd888e5f9c5f9731e6c623d5d715d1dfcf399ca4..87615fbd0f5ec814b71815b848eca6baac6fed02 100644
--- a/libcxx/test/libcxx/diagnostics/nodiscard_extensions.pass.cpp
+++ b/libcxx/test/libcxx/diagnostics/nodiscard_extensions.pass.cpp
@@ -21,8 +21,10 @@
 
 #include "test_macros.h"
 
-int main() {
+int main(int, char**) {
   {
     std::get_temporary_buffer<int>(1); // intentional memory leak.
   }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/diagnostics/std.exceptions/version.pass.cpp b/libcxx/test/libcxx/diagnostics/std.exceptions/version.pass.cpp
index 860c18795171e0412f54e5337a4925203d955b80..147f4d2b9b3d245d369d18592325b06388085e7c 100644
--- a/libcxx/test/libcxx/diagnostics/std.exceptions/version.pass.cpp
+++ b/libcxx/test/libcxx/diagnostics/std.exceptions/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/diagnostics/syserr/version.pass.cpp b/libcxx/test/libcxx/diagnostics/syserr/version.pass.cpp
index 6f2dde8efae34c46100122a063fe6288f7d6ff20..4b987a668ad688da28f8cb1c6d8599b1ee522c4e 100644
--- a/libcxx/test/libcxx/diagnostics/syserr/version.pass.cpp
+++ b/libcxx/test/libcxx/diagnostics/syserr/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/double_include.sh.cpp b/libcxx/test/libcxx/double_include.sh.cpp
index 249b90947f47cde7d2bd61e9c27596b231514ac0..a167b0a586cc13f2f4c7318cb4057be60184b972 100644
--- a/libcxx/test/libcxx/double_include.sh.cpp
+++ b/libcxx/test/libcxx/double_include.sh.cpp
@@ -168,5 +168,5 @@
 #include <ext/hash_set>
 
 #if defined(WITH_MAIN)
-int main() {}
+int main(int, char**) { return 0; }
 #endif
diff --git a/libcxx/test/libcxx/experimental/algorithms/header.algorithm.synop/includes.pass.cpp b/libcxx/test/libcxx/experimental/algorithms/header.algorithm.synop/includes.pass.cpp
index ecbf562f8802f4b46473bd2cf97362b269afd2b7..271e94347d168c1d7206d632d69b6d0f452cc1e3 100644
--- a/libcxx/test/libcxx/experimental/algorithms/header.algorithm.synop/includes.pass.cpp
+++ b/libcxx/test/libcxx/experimental/algorithms/header.algorithm.synop/includes.pass.cpp
@@ -14,6 +14,8 @@
 #  error "<experimental/algorithm> must include <algorithm>"
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/experimental/algorithms/version.pass.cpp b/libcxx/test/libcxx/experimental/algorithms/version.pass.cpp
index d0107209fb8faa61b3bd620d79ea1ce5cc642ee2..c43ad68a96efce2514c099ff2ee83970ef0878ee 100644
--- a/libcxx/test/libcxx/experimental/algorithms/version.pass.cpp
+++ b/libcxx/test/libcxx/experimental/algorithms/version.pass.cpp
@@ -14,6 +14,8 @@
 #  error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/experimental/diagnostics/syserr/use_header_warning.fail.cpp b/libcxx/test/libcxx/experimental/diagnostics/syserr/use_header_warning.fail.cpp
index 5d72e5e9340301b92ab09f5ff1287efbdc83ac16..a7fef5e734a5e2b7c3d0ed4e9688d906e0ff350b 100644
--- a/libcxx/test/libcxx/experimental/diagnostics/syserr/use_header_warning.fail.cpp
+++ b/libcxx/test/libcxx/experimental/diagnostics/syserr/use_header_warning.fail.cpp
@@ -14,4 +14,6 @@
 
 // expected-error@experimental/system_error:* {{"<experimental/system_error> has been removed. Use <system_error> instead."}}
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/libcxx/experimental/diagnostics/syserr/version.pass.cpp b/libcxx/test/libcxx/experimental/diagnostics/syserr/version.pass.cpp
index 7d52c955ddc2ec173af37919bcd013a612d79fbf..4f6d28c4c354940a1ace95030f339b7315497cff 100644
--- a/libcxx/test/libcxx/experimental/diagnostics/syserr/version.pass.cpp
+++ b/libcxx/test/libcxx/experimental/diagnostics/syserr/version.pass.cpp
@@ -17,4 +17,6 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/libcxx/experimental/filesystem/version.pass.cpp b/libcxx/test/libcxx/experimental/filesystem/version.pass.cpp
index 09994b6b35f506fdd01ddfee5e2694f00a68fbd2..d8b2cbbd14f33961008158a0ee50fbc2021992f5 100644
--- a/libcxx/test/libcxx/experimental/filesystem/version.pass.cpp
+++ b/libcxx/test/libcxx/experimental/filesystem/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/experimental/language.support/support.coroutines/dialect_support.sh.cpp b/libcxx/test/libcxx/experimental/language.support/support.coroutines/dialect_support.sh.cpp
index 5dfdbe840ad8a1012645bebf261e3b1db1307f86..237fbc4bbd615ac06a2f3534c0822f88a806ca80 100644
--- a/libcxx/test/libcxx/experimental/language.support/support.coroutines/dialect_support.sh.cpp
+++ b/libcxx/test/libcxx/experimental/language.support/support.coroutines/dialect_support.sh.cpp
@@ -49,10 +49,12 @@ MyFuture test_coro() {
   co_return;
 }
 
-int main()
+int main(int, char**)
 {
   MyFuture f = test_coro();
   while (!f.p.done())
     f.p.resume();
   f.p.destroy();
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/experimental/language.support/support.coroutines/version.sh.cpp b/libcxx/test/libcxx/experimental/language.support/support.coroutines/version.sh.cpp
index a80e3013b40ee3948fd29b68070c54acac73c079..b11ea931f92122ad16beeb3d3ec3fcecbf8da447 100644
--- a/libcxx/test/libcxx/experimental/language.support/support.coroutines/version.sh.cpp
+++ b/libcxx/test/libcxx/experimental/language.support/support.coroutines/version.sh.cpp
@@ -19,6 +19,8 @@
 #error _LIBCPP_VERSION must be defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_piecewise_pair.pass.cpp b/libcxx/test/libcxx/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_piecewise_pair.pass.cpp
index b92771b4b1298414d58e3a16fa319b4002d656ea..e12d31d5ff7aaf8000f7ab741e9ce2bcab7d9df5 100644
--- a/libcxx/test/libcxx/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_piecewise_pair.pass.cpp
+++ b/libcxx/test/libcxx/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_piecewise_pair.pass.cpp
@@ -103,7 +103,7 @@ struct CountCopiesAllocV2 {
 };
 
 
-int main()
+int main(int, char**)
 {
     {
         using T = CountCopies;
@@ -167,4 +167,6 @@ int main()
         assert(p.first.alloc == h.M);
         assert(p.second.count == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/db_deallocate.pass.cpp b/libcxx/test/libcxx/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/db_deallocate.pass.cpp
index ed583e4e0c9ba4629e5e88245ecef1e1e472b282..38fa265f8ed2cf3a904646d23086f742da7d2748 100644
--- a/libcxx/test/libcxx/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/db_deallocate.pass.cpp
+++ b/libcxx/test/libcxx/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/db_deallocate.pass.cpp
@@ -26,7 +26,7 @@ int AssertCount = 0;
 
 namespace ex = std::experimental::pmr;
 
-int main()
+int main(int, char**)
 {
     using Alloc = ex::polymorphic_allocator<int>;
     using Traits = std::allocator_traits<Alloc>;
@@ -38,4 +38,6 @@ int main()
     assert(AssertCount == 0);
     a.deallocate(nullptr, maxSize + 1);
     assert(AssertCount == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/experimental/memory/memory.resource.adaptor/memory.resource.adaptor.mem/db_deallocate.pass.cpp b/libcxx/test/libcxx/experimental/memory/memory.resource.adaptor/memory.resource.adaptor.mem/db_deallocate.pass.cpp
index cb40761074f9ad3e3eceed27c5e72ac7786d9719..d7a56be43877d0f5b660cb89bee7604292b12d93 100644
--- a/libcxx/test/libcxx/experimental/memory/memory.resource.adaptor/memory.resource.adaptor.mem/db_deallocate.pass.cpp
+++ b/libcxx/test/libcxx/experimental/memory/memory.resource.adaptor/memory.resource.adaptor.mem/db_deallocate.pass.cpp
@@ -26,7 +26,7 @@ int AssertCount = 0;
 
 namespace ex = std::experimental::pmr;
 
-int main()
+int main(int, char**)
 {
     using Alloc = NullAllocator<char>;
 
@@ -41,4 +41,6 @@ int main()
     assert(AssertCount == 0);
     m1.deallocate(nullptr, maxSize + 1);
     assert(AssertCount >= 1);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_deque_libcpp_version.pass.cpp b/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_deque_libcpp_version.pass.cpp
index 78586781cf037c9b37e0741fb2132b46ae45568e..53423a7a7a8bc64afc0996512dac573b5e775411 100644
--- a/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_deque_libcpp_version.pass.cpp
+++ b/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_deque_libcpp_version.pass.cpp
@@ -16,6 +16,8 @@
 #error header must provide _LIBCPP_VERSION
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_forward_list_libcpp_version.pass.cpp b/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_forward_list_libcpp_version.pass.cpp
index 35faa8389676c8c751431ae4e4d06fa2c256489b..8f71d91abad8f294d83df2534f7094e97922df69 100644
--- a/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_forward_list_libcpp_version.pass.cpp
+++ b/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_forward_list_libcpp_version.pass.cpp
@@ -16,6 +16,8 @@
 #error header must provide _LIBCPP_VERSION
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_list_libcpp_version.pass.cpp b/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_list_libcpp_version.pass.cpp
index e29220621704742e256d9aa094c984a92d33857b..3cdf4794d3156481ff17553428c93befa1292740 100644
--- a/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_list_libcpp_version.pass.cpp
+++ b/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_list_libcpp_version.pass.cpp
@@ -16,6 +16,8 @@
 #error header must provide _LIBCPP_VERSION
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_map_libcpp_version.pass.cpp b/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_map_libcpp_version.pass.cpp
index f0caac4275f45db98cce920fdeeb3d5845472c30..94b636f66756d83e0c7005331e3f13661256d732 100644
--- a/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_map_libcpp_version.pass.cpp
+++ b/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_map_libcpp_version.pass.cpp
@@ -16,6 +16,8 @@
 #error header must provide _LIBCPP_VERSION
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_regex_libcpp_version.pass.cpp b/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_regex_libcpp_version.pass.cpp
index 0af172b61e186ebaac3785cdd469e31745127409..a34c52301b68e5fc774996514984a7c368569ab3 100644
--- a/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_regex_libcpp_version.pass.cpp
+++ b/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_regex_libcpp_version.pass.cpp
@@ -16,6 +16,8 @@
 #error header must provide _LIBCPP_VERSION
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_set_libcpp_version.pass.cpp b/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_set_libcpp_version.pass.cpp
index ca5a9faff0f3f633647728cfc4a3cf1a338b66d3..70e34c9b0ca39635420e71a3d682dbec795caee0 100644
--- a/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_set_libcpp_version.pass.cpp
+++ b/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_set_libcpp_version.pass.cpp
@@ -16,6 +16,8 @@
 #error header must provide _LIBCPP_VERSION
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_string_libcpp_version.pass.cpp b/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_string_libcpp_version.pass.cpp
index 99faace64cf9d9d68371d1c777808b5272446a3d..7969b4f25b8f4d15bbda61d44afefbe6b6a29621 100644
--- a/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_string_libcpp_version.pass.cpp
+++ b/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_string_libcpp_version.pass.cpp
@@ -16,6 +16,8 @@
 #error header must provide _LIBCPP_VERSION
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_unordered_map_libcpp_version.pass.cpp b/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_unordered_map_libcpp_version.pass.cpp
index ad49a733876ece98dcab9fbf0eb374a02fa35e4d..71cfb2c1ea80218aea6b10dcc90c2d2ecddf51bc 100644
--- a/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_unordered_map_libcpp_version.pass.cpp
+++ b/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_unordered_map_libcpp_version.pass.cpp
@@ -16,6 +16,8 @@
 #error header must provide _LIBCPP_VERSION
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_unordered_set_libcpp_version.pass.cpp b/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_unordered_set_libcpp_version.pass.cpp
index 619bdb446defae66059d2a67b7f5ba7da96ca034..55a992c7135b64cb7aa2d4532d0e0ea5a52eee22 100644
--- a/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_unordered_set_libcpp_version.pass.cpp
+++ b/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_unordered_set_libcpp_version.pass.cpp
@@ -16,6 +16,8 @@
 #error header must provide _LIBCPP_VERSION
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_vector_libcpp_version.pass.cpp b/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_vector_libcpp_version.pass.cpp
index eb831d6d7ae62df0938b291ec3f5148aa0b1156f..89a8fb0aab9f6e00d55bb6fd711f47b4d9a68895 100644
--- a/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_vector_libcpp_version.pass.cpp
+++ b/libcxx/test/libcxx/experimental/memory/memory.resource.aliases/header_vector_libcpp_version.pass.cpp
@@ -16,6 +16,8 @@
 #error header must provide _LIBCPP_VERSION
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/experimental/memory/memory.resource.global/global_memory_resource_lifetime.pass.cpp b/libcxx/test/libcxx/experimental/memory/memory.resource.global/global_memory_resource_lifetime.pass.cpp
index a3c0ba1ea1b1a0dbd26d85197710d748291fc716..abd737e0858e43fcbd12ef3f1194b2001161926f 100644
--- a/libcxx/test/libcxx/experimental/memory/memory.resource.global/global_memory_resource_lifetime.pass.cpp
+++ b/libcxx/test/libcxx/experimental/memory/memory.resource.global/global_memory_resource_lifetime.pass.cpp
@@ -53,8 +53,10 @@ ex::memory_resource* resource = ex::get_default_resource();
 POSType constructed_after_resources(resource, resource->allocate(1024), 1024);
 POSType constructed_after_resources2(nullptr, resource->allocate(1024), 1024);
 
-int main()
+int main(int, char**)
 {
     swap(constructed_after_resources, constructed_before_resources);
     swap(constructed_before_resources2, constructed_after_resources2);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/experimental/memory/memory.resource.global/new_delete_resource_lifetime.pass.cpp b/libcxx/test/libcxx/experimental/memory/memory.resource.global/new_delete_resource_lifetime.pass.cpp
index c6b4011cec03bf00a238950656a28dfc858aaf22..dc2e9161fed8723a72a4aae747a21e4679e582a2 100644
--- a/libcxx/test/libcxx/experimental/memory/memory.resource.global/new_delete_resource_lifetime.pass.cpp
+++ b/libcxx/test/libcxx/experimental/memory/memory.resource.global/new_delete_resource_lifetime.pass.cpp
@@ -46,7 +46,9 @@ ex::memory_resource* resource = ex::new_delete_resource();
 
 POSType constructed_after_resources(resource, resource->allocate(1024), 1024);
 
-int main()
+int main(int, char**)
 {
     swap(constructed_after_resources, constructed_before_resources);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/experimental/memory/memory.resource.synop/version.pass.cpp b/libcxx/test/libcxx/experimental/memory/memory.resource.synop/version.pass.cpp
index a19049c33f115a3a80d36bd45eb73296a6d39750..e8d628581820247eb8bb6166eb4419301c645e4c 100644
--- a/libcxx/test/libcxx/experimental/memory/memory.resource.synop/version.pass.cpp
+++ b/libcxx/test/libcxx/experimental/memory/memory.resource.synop/version.pass.cpp
@@ -16,6 +16,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/experimental/numerics/numeric.ops/use_header_warning.fail.cpp b/libcxx/test/libcxx/experimental/numerics/numeric.ops/use_header_warning.fail.cpp
index 6560101553f5dc06db6a3b919825515de1ba58d6..d675acc268f931c00e55c9fcc893cb36425611ba 100644
--- a/libcxx/test/libcxx/experimental/numerics/numeric.ops/use_header_warning.fail.cpp
+++ b/libcxx/test/libcxx/experimental/numerics/numeric.ops/use_header_warning.fail.cpp
@@ -14,4 +14,6 @@
 
 // expected-error@experimental/numeric:* {{"<experimental/numeric> has been removed. Use <numeric> instead."}}
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/libcxx/experimental/numerics/numeric.ops/version.pass.cpp b/libcxx/test/libcxx/experimental/numerics/numeric.ops/version.pass.cpp
index 7295852d3324b81589edb5d609eed7192810e566..f8b642d07b9a2c3c8cfcdca1a9c362b098d451f6 100644
--- a/libcxx/test/libcxx/experimental/numerics/numeric.ops/version.pass.cpp
+++ b/libcxx/test/libcxx/experimental/numerics/numeric.ops/version.pass.cpp
@@ -17,4 +17,6 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/libcxx/experimental/strings/string.view/use_header_warning.fail.cpp b/libcxx/test/libcxx/experimental/strings/string.view/use_header_warning.fail.cpp
index 10a2ebc12250872bab7f16a5e5b7a498b5778116..139bc2d1f7820ea58679fbc688d9d25db4dc2550 100644
--- a/libcxx/test/libcxx/experimental/strings/string.view/use_header_warning.fail.cpp
+++ b/libcxx/test/libcxx/experimental/strings/string.view/use_header_warning.fail.cpp
@@ -14,4 +14,6 @@
 
 // expected-error@experimental/string_view:* {{"<experimental/string_view> has been removed. Use <string_view> instead."}}
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/libcxx/experimental/strings/string.view/version.pass.cpp b/libcxx/test/libcxx/experimental/strings/string.view/version.pass.cpp
index c697d67b104f084e05cd8548eaa47d894a6e4cab..7300a5501ebbf4c5233ae7b15df588d0c812ddc7 100644
--- a/libcxx/test/libcxx/experimental/strings/string.view/version.pass.cpp
+++ b/libcxx/test/libcxx/experimental/strings/string.view/version.pass.cpp
@@ -17,4 +17,6 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/libcxx/experimental/utilities/any/use_header_warning.fail.cpp b/libcxx/test/libcxx/experimental/utilities/any/use_header_warning.fail.cpp
index 69a67ffafd3ed3efcede1be71cc5940148a5d8e7..1b8918e8090a41311083055d0c61617c83b881a0 100644
--- a/libcxx/test/libcxx/experimental/utilities/any/use_header_warning.fail.cpp
+++ b/libcxx/test/libcxx/experimental/utilities/any/use_header_warning.fail.cpp
@@ -14,4 +14,6 @@
 
 // expected-error@experimental/any:* {{"<experimental/any> has been removed. Use <any> instead."}}
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/libcxx/experimental/utilities/any/version.pass.cpp b/libcxx/test/libcxx/experimental/utilities/any/version.pass.cpp
index ed8d6f7e8662dce44e830d725f9682d3ce2ba311..ecfdecfea93335d528ff7b1a6ee6b6db635f7d94 100644
--- a/libcxx/test/libcxx/experimental/utilities/any/version.pass.cpp
+++ b/libcxx/test/libcxx/experimental/utilities/any/version.pass.cpp
@@ -17,4 +17,6 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/libcxx/experimental/utilities/meta/version.pass.cpp b/libcxx/test/libcxx/experimental/utilities/meta/version.pass.cpp
index 9dd3ca83a09bbda65801dcf31e8a9e51470d6fb6..3568c6fe53d3ff7ca3b3cc9c24dde283577a4a6f 100644
--- a/libcxx/test/libcxx/experimental/utilities/meta/version.pass.cpp
+++ b/libcxx/test/libcxx/experimental/utilities/meta/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/experimental/utilities/optional/use_header_warning.fail.cpp b/libcxx/test/libcxx/experimental/utilities/optional/use_header_warning.fail.cpp
index 8b23ac69ab6d56d337a06258abde4e3e5aa0275c..d2bb9e6e96755a312196c10ddd6ec9cb139d1d46 100644
--- a/libcxx/test/libcxx/experimental/utilities/optional/use_header_warning.fail.cpp
+++ b/libcxx/test/libcxx/experimental/utilities/optional/use_header_warning.fail.cpp
@@ -14,4 +14,6 @@
 
 // expected-error@experimental/optional:* {{"<experimental/optional> has been removed. Use <optional> instead."}}
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/libcxx/experimental/utilities/optional/version.pass.cpp b/libcxx/test/libcxx/experimental/utilities/optional/version.pass.cpp
index ead45ebf54f10cef5a9d81fdaa8507ac64f334d5..0e84f241a65750fdc09f6969c813739a89ce9830 100644
--- a/libcxx/test/libcxx/experimental/utilities/optional/version.pass.cpp
+++ b/libcxx/test/libcxx/experimental/utilities/optional/version.pass.cpp
@@ -17,4 +17,6 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/libcxx/experimental/utilities/ratio/use_header_warning.fail.cpp b/libcxx/test/libcxx/experimental/utilities/ratio/use_header_warning.fail.cpp
index 682872fce4af66d41026d1660aab4a0ed09ef899..a6578ef48b804d91b3a4a42ed4e346e163b422ba 100644
--- a/libcxx/test/libcxx/experimental/utilities/ratio/use_header_warning.fail.cpp
+++ b/libcxx/test/libcxx/experimental/utilities/ratio/use_header_warning.fail.cpp
@@ -14,4 +14,6 @@
 
 // expected-error@experimental/ratio:* {{"<experimental/ratio> has been removed. Use <ratio> instead."}}
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/libcxx/experimental/utilities/ratio/version.pass.cpp b/libcxx/test/libcxx/experimental/utilities/ratio/version.pass.cpp
index 990b91c7159bdb9105eaac14e46b7d1b5ed5ce53..0357c79efeea116b1a3d81ee7905f0f2eceb09b7 100644
--- a/libcxx/test/libcxx/experimental/utilities/ratio/version.pass.cpp
+++ b/libcxx/test/libcxx/experimental/utilities/ratio/version.pass.cpp
@@ -17,4 +17,6 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/libcxx/experimental/utilities/time/use_header_warning.fail.cpp b/libcxx/test/libcxx/experimental/utilities/time/use_header_warning.fail.cpp
index fc2dc3ad7a93d227b11cfe4779a43b2d4ea037bc..093d6fca418136b9746c2c34781f3873bcc9d039 100644
--- a/libcxx/test/libcxx/experimental/utilities/time/use_header_warning.fail.cpp
+++ b/libcxx/test/libcxx/experimental/utilities/time/use_header_warning.fail.cpp
@@ -14,4 +14,6 @@
 
 // expected-error@experimental/chrono:* {{"<experimental/chrono> has been removed. Use <chrono> instead."}}
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/libcxx/experimental/utilities/time/version.pass.cpp b/libcxx/test/libcxx/experimental/utilities/time/version.pass.cpp
index f14728679d3199c2650bc5aea9a751989befaed7..5ff26f7b2dcdb031bacd760b72c016f70e37f357 100644
--- a/libcxx/test/libcxx/experimental/utilities/time/version.pass.cpp
+++ b/libcxx/test/libcxx/experimental/utilities/time/version.pass.cpp
@@ -17,4 +17,6 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/libcxx/experimental/utilities/tuple/use_header_warning.fail.cpp b/libcxx/test/libcxx/experimental/utilities/tuple/use_header_warning.fail.cpp
index 0bc33eca7007014ebda9e5beb3b9bd28143f7473..6b378c2ce9246df5a5422c0e067c857a2c8abe74 100644
--- a/libcxx/test/libcxx/experimental/utilities/tuple/use_header_warning.fail.cpp
+++ b/libcxx/test/libcxx/experimental/utilities/tuple/use_header_warning.fail.cpp
@@ -14,4 +14,6 @@
 
 // expected-error@experimental/tuple:* {{"<experimental/tuple> has been removed. Use <tuple> instead."}}
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/libcxx/experimental/utilities/tuple/version.pass.cpp b/libcxx/test/libcxx/experimental/utilities/tuple/version.pass.cpp
index 8e4bae634ee682bb7d052618b2155d9ad33297b9..4c1e305a45644869824fb9f1b63e51c6f6e80851 100644
--- a/libcxx/test/libcxx/experimental/utilities/tuple/version.pass.cpp
+++ b/libcxx/test/libcxx/experimental/utilities/tuple/version.pass.cpp
@@ -17,4 +17,6 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/libcxx/experimental/utilities/utility/version.pass.cpp b/libcxx/test/libcxx/experimental/utilities/utility/version.pass.cpp
index 024c5616089c773a43580c72e70f992d4bf347ce..5ba32b1ca207d61c05316b11242fa655f8d36bcc 100644
--- a/libcxx/test/libcxx/experimental/utilities/utility/version.pass.cpp
+++ b/libcxx/test/libcxx/experimental/utilities/utility/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/extensions/hash/specializations.fail.cpp b/libcxx/test/libcxx/extensions/hash/specializations.fail.cpp
index 19a726bdc1dfb7c93e8263831f13f1420de0fc78..f81ec5dacb91ec4fa91d636af94c30b154da2314 100644
--- a/libcxx/test/libcxx/extensions/hash/specializations.fail.cpp
+++ b/libcxx/test/libcxx/extensions/hash/specializations.fail.cpp
@@ -10,7 +10,9 @@
 #include <ext/hash_map>
 #include <string>
 
-int main()
+int main(int, char**)
 {
     assert(__gnu_cxx::hash<std::string>()(std::string()) == 0);  // error
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/extensions/hash/specializations.pass.cpp b/libcxx/test/libcxx/extensions/hash/specializations.pass.cpp
index a3f969ba1a5517088d2c3ba833553bac7f23b516..9397bbc402937781d42c47b8a666c8172724ea22 100644
--- a/libcxx/test/libcxx/extensions/hash/specializations.pass.cpp
+++ b/libcxx/test/libcxx/extensions/hash/specializations.pass.cpp
@@ -12,7 +12,7 @@
 #include <ext/hash_map>
 #include <string>
 
-int main()
+int main(int, char**)
 {
     char str[] = "test";
     assert(__gnu_cxx::hash<const char *>()("test") ==
@@ -27,4 +27,6 @@ int main()
     assert(__gnu_cxx::hash<unsigned int>()(42) == 42);
     assert(__gnu_cxx::hash<long>()(42) == 42);
     assert(__gnu_cxx::hash<unsigned long>()(42) == 42);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/extensions/hash_map/const_iterator.fail.cpp b/libcxx/test/libcxx/extensions/hash_map/const_iterator.fail.cpp
index b6389db49dafd9ec4769875419d6c8ffefc0c440..db09e40801a1fcff63be6c46ceb1d2f1b5c1fd13 100644
--- a/libcxx/test/libcxx/extensions/hash_map/const_iterator.fail.cpp
+++ b/libcxx/test/libcxx/extensions/hash_map/const_iterator.fail.cpp
@@ -8,10 +8,12 @@
 
 #include <ext/hash_map>
 
-int main()
+int main(int, char**)
 {
     __gnu_cxx::hash_map<int, int> m;
     m[1] = 1;
     const __gnu_cxx::hash_map<int, int> &cm = m;
     cm.find(1)->second = 2;  // error
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/extensions/nothing_to_do.pass.cpp b/libcxx/test/libcxx/extensions/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/libcxx/extensions/nothing_to_do.pass.cpp
+++ b/libcxx/test/libcxx/extensions/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/fuzzing/nth_element.cpp b/libcxx/test/libcxx/fuzzing/nth_element.cpp
index a7f9e9c224df43d6cb294a2fea28106a202d7be4..482aeb65ffe8928d551222cf78e553f398b45ca5 100644
--- a/libcxx/test/libcxx/fuzzing/nth_element.cpp
+++ b/libcxx/test/libcxx/fuzzing/nth_element.cpp
@@ -25,7 +25,7 @@ const char * test_cases[] = {
 const size_t k_num_tests = sizeof(test_cases)/sizeof(test_cases[0]);
 
 
-int main ()
+int main(int, char**)
 {
 	for (size_t i = 0; i < k_num_tests; ++i)
 		{
diff --git a/libcxx/test/libcxx/fuzzing/partial_sort.cpp b/libcxx/test/libcxx/fuzzing/partial_sort.cpp
index 2d4d01a0926fac9c66bb89975a7ea145f1d4d134..4f35766633024cc65b618d473154944220336f60 100644
--- a/libcxx/test/libcxx/fuzzing/partial_sort.cpp
+++ b/libcxx/test/libcxx/fuzzing/partial_sort.cpp
@@ -25,7 +25,7 @@ const char * test_cases[] = {
 const size_t k_num_tests = sizeof(test_cases)/sizeof(test_cases[0]);
 
 
-int main ()
+int main(int, char**)
 {
 	for (size_t i = 0; i < k_num_tests; ++i)
 		{
diff --git a/libcxx/test/libcxx/fuzzing/partial_sort_copy.cpp b/libcxx/test/libcxx/fuzzing/partial_sort_copy.cpp
index 2a7ccbef455b12ad0f12c79805fbc4273ccbdc3c..b569f55ebd845f995e5dc2a9b97f65a0e420ff07 100644
--- a/libcxx/test/libcxx/fuzzing/partial_sort_copy.cpp
+++ b/libcxx/test/libcxx/fuzzing/partial_sort_copy.cpp
@@ -25,7 +25,7 @@ const char * test_cases[] = {
 const size_t k_num_tests = sizeof(test_cases)/sizeof(test_cases[0]);
 
 
-int main ()
+int main(int, char**)
 {
 	for (size_t i = 0; i < k_num_tests; ++i)
 		{
diff --git a/libcxx/test/libcxx/fuzzing/partition.cpp b/libcxx/test/libcxx/fuzzing/partition.cpp
index c03f17f98000bf73e199765ce036c406d34154b0..0833e38e21115c48515e0f37acdaf37168b4b6fa 100644
--- a/libcxx/test/libcxx/fuzzing/partition.cpp
+++ b/libcxx/test/libcxx/fuzzing/partition.cpp
@@ -25,7 +25,7 @@ const char * test_cases[] = {
 const size_t k_num_tests = sizeof(test_cases)/sizeof(test_cases[0]);
 
 
-int main ()
+int main(int, char**)
 {
 	for (size_t i = 0; i < k_num_tests; ++i)
 		{
diff --git a/libcxx/test/libcxx/fuzzing/partition_copy.cpp b/libcxx/test/libcxx/fuzzing/partition_copy.cpp
index f7148bbd0ce5d11853ff81c682ff048d5b3a475b..f336a14cab6da42a5867e5d847a4d10e399c67da 100644
--- a/libcxx/test/libcxx/fuzzing/partition_copy.cpp
+++ b/libcxx/test/libcxx/fuzzing/partition_copy.cpp
@@ -25,7 +25,7 @@ const char * test_cases[] = {
 const size_t k_num_tests = sizeof(test_cases)/sizeof(test_cases[0]);
 
 
-int main ()
+int main(int, char**)
 {
 	for (size_t i = 0; i < k_num_tests; ++i)
 		{
diff --git a/libcxx/test/libcxx/fuzzing/regex_ECMAScript.cpp b/libcxx/test/libcxx/fuzzing/regex_ECMAScript.cpp
index 51ca6efa77c6b87e053b2f55f9e00e55f550c1c7..ca9a7dae5210325a51478b4521bd646675d05eaa 100644
--- a/libcxx/test/libcxx/fuzzing/regex_ECMAScript.cpp
+++ b/libcxx/test/libcxx/fuzzing/regex_ECMAScript.cpp
@@ -24,7 +24,7 @@ const char * test_cases[] = {
 
 const size_t k_num_tests = sizeof(test_cases)/sizeof(test_cases[0]);
 
-int main ()
+int main(int, char**)
 {
 	for (size_t i = 0; i < k_num_tests; ++i)
 		{
diff --git a/libcxx/test/libcxx/fuzzing/regex_POSIX.cpp b/libcxx/test/libcxx/fuzzing/regex_POSIX.cpp
index 3fcd1bcda8f3dfdf64f98fbc16447316f2dd7713..69f40de6d1909a44a303abb42646d2ead84597e1 100644
--- a/libcxx/test/libcxx/fuzzing/regex_POSIX.cpp
+++ b/libcxx/test/libcxx/fuzzing/regex_POSIX.cpp
@@ -24,7 +24,7 @@ const char * test_cases[] = {
 
 const size_t k_num_tests = sizeof(test_cases)/sizeof(test_cases[0]);
 
-int main ()
+int main(int, char**)
 {
 	for (size_t i = 0; i < k_num_tests; ++i)
 		{
diff --git a/libcxx/test/libcxx/fuzzing/regex_awk.cpp b/libcxx/test/libcxx/fuzzing/regex_awk.cpp
index 51ca6efa77c6b87e053b2f55f9e00e55f550c1c7..ca9a7dae5210325a51478b4521bd646675d05eaa 100644
--- a/libcxx/test/libcxx/fuzzing/regex_awk.cpp
+++ b/libcxx/test/libcxx/fuzzing/regex_awk.cpp
@@ -24,7 +24,7 @@ const char * test_cases[] = {
 
 const size_t k_num_tests = sizeof(test_cases)/sizeof(test_cases[0]);
 
-int main ()
+int main(int, char**)
 {
 	for (size_t i = 0; i < k_num_tests; ++i)
 		{
diff --git a/libcxx/test/libcxx/fuzzing/regex_egrep.cpp b/libcxx/test/libcxx/fuzzing/regex_egrep.cpp
index e44c9e16321e1321a53ab223766c49986ec9c789..f350f63e334c5156beacc6944b9ce7241816a4b8 100644
--- a/libcxx/test/libcxx/fuzzing/regex_egrep.cpp
+++ b/libcxx/test/libcxx/fuzzing/regex_egrep.cpp
@@ -24,7 +24,7 @@ const char * test_cases[] = {
 
 const size_t k_num_tests = sizeof(test_cases)/sizeof(test_cases[0]);
 
-int main ()
+int main(int, char**)
 {
 	for (size_t i = 0; i < k_num_tests; ++i)
 		{
diff --git a/libcxx/test/libcxx/fuzzing/regex_extended.cpp b/libcxx/test/libcxx/fuzzing/regex_extended.cpp
index dcb7077eba75f70b95875e0441e62713b1849384..ae55f5bb8372392e6da38cabac0e865c7733fb6f 100644
--- a/libcxx/test/libcxx/fuzzing/regex_extended.cpp
+++ b/libcxx/test/libcxx/fuzzing/regex_extended.cpp
@@ -24,7 +24,7 @@ const char * test_cases[] = {
 
 const size_t k_num_tests = sizeof(test_cases)/sizeof(test_cases[0]);
 
-int main ()
+int main(int, char**)
 {
 	for (size_t i = 0; i < k_num_tests; ++i)
 		{
diff --git a/libcxx/test/libcxx/fuzzing/regex_grep.cpp b/libcxx/test/libcxx/fuzzing/regex_grep.cpp
index 50ef9b9410d41b2d01d53945a0f61eb479ad3d18..ac497b3a9fcf1df557efb54cad66ac094fc2985b 100644
--- a/libcxx/test/libcxx/fuzzing/regex_grep.cpp
+++ b/libcxx/test/libcxx/fuzzing/regex_grep.cpp
@@ -24,7 +24,7 @@ const char * test_cases[] = {
 
 const size_t k_num_tests = sizeof(test_cases)/sizeof(test_cases[0]);
 
-int main ()
+int main(int, char**)
 {
 	for (size_t i = 0; i < k_num_tests; ++i)
 		{
diff --git a/libcxx/test/libcxx/fuzzing/sort.cpp b/libcxx/test/libcxx/fuzzing/sort.cpp
index 924c4cf88fb94ed7f7387a460f46fb572cc65847..43b9064de0331ff6a5d60f4b5dca65c6ab21dc01 100644
--- a/libcxx/test/libcxx/fuzzing/sort.cpp
+++ b/libcxx/test/libcxx/fuzzing/sort.cpp
@@ -25,7 +25,7 @@ const char * test_cases[] = {
 const size_t k_num_tests = sizeof(test_cases)/sizeof(test_cases[0]);
 
 
-int main ()
+int main(int, char**)
 {
 	for (size_t i = 0; i < k_num_tests; ++i)
 		{
diff --git a/libcxx/test/libcxx/fuzzing/stable_partition.cpp b/libcxx/test/libcxx/fuzzing/stable_partition.cpp
index af11cb362423bee102d0611b2c23ffe7577d2eb4..b236190cbf275e3bd26b213ca51ea3858e57b815 100644
--- a/libcxx/test/libcxx/fuzzing/stable_partition.cpp
+++ b/libcxx/test/libcxx/fuzzing/stable_partition.cpp
@@ -25,7 +25,7 @@ const char * test_cases[] = {
 const size_t k_num_tests = sizeof(test_cases)/sizeof(test_cases[0]);
 
 
-int main ()
+int main(int, char**)
 {
 	for (size_t i = 0; i < k_num_tests; ++i)
 		{
diff --git a/libcxx/test/libcxx/fuzzing/stable_sort.cpp b/libcxx/test/libcxx/fuzzing/stable_sort.cpp
index c32be24864f3e7ebf76e451826c20d0e3a9c4e02..1c8ac4904256cddb3cf188ca91c327052036923a 100644
--- a/libcxx/test/libcxx/fuzzing/stable_sort.cpp
+++ b/libcxx/test/libcxx/fuzzing/stable_sort.cpp
@@ -25,7 +25,7 @@ const char * test_cases[] = {
 const size_t k_num_tests = sizeof(test_cases)/sizeof(test_cases[0]);
 
 
-int main ()
+int main(int, char**)
 {
 	for (size_t i = 0; i < k_num_tests; ++i)
 		{
diff --git a/libcxx/test/libcxx/fuzzing/unique.cpp b/libcxx/test/libcxx/fuzzing/unique.cpp
index 57317373f9b7f30357325b1454bb46bf5e8548db..cab512eb89e874679b8a74c74800f914857913d0 100644
--- a/libcxx/test/libcxx/fuzzing/unique.cpp
+++ b/libcxx/test/libcxx/fuzzing/unique.cpp
@@ -25,7 +25,7 @@ const char * test_cases[] = {
 const size_t k_num_tests = sizeof(test_cases)/sizeof(test_cases[0]);
 
 
-int main ()
+int main(int, char**)
 {
 	for (size_t i = 0; i < k_num_tests; ++i)
 		{
diff --git a/libcxx/test/libcxx/fuzzing/unique_copy.cpp b/libcxx/test/libcxx/fuzzing/unique_copy.cpp
index c513e60bdc518de704fcd1059e94cac1ae67ef35..311eb4cf64e30d3647bbec22cecc1b9c6ea8380a 100644
--- a/libcxx/test/libcxx/fuzzing/unique_copy.cpp
+++ b/libcxx/test/libcxx/fuzzing/unique_copy.cpp
@@ -25,7 +25,7 @@ const char * test_cases[] = {
 const size_t k_num_tests = sizeof(test_cases)/sizeof(test_cases[0]);
 
 
-int main ()
+int main(int, char**)
 {
 	for (size_t i = 0; i < k_num_tests; ++i)
 		{
diff --git a/libcxx/test/libcxx/include_as_c.sh.cpp b/libcxx/test/libcxx/include_as_c.sh.cpp
index f0dd9bef17479e96146241f1788a59300bcf93fc..c056f61ae71a492b6ad509cd263bd5da2ef12ca0 100644
--- a/libcxx/test/libcxx/include_as_c.sh.cpp
+++ b/libcxx/test/libcxx/include_as_c.sh.cpp
@@ -33,4 +33,8 @@
 #include <wchar.h>
 #include <wctype.h>
 
-int main() {}
+int main(int argc, char **argv) {
+  (void)argc;
+  (void)argv;
+  return 0;
+}
diff --git a/libcxx/test/libcxx/input.output/file.streams/c.files/no.global.filesystem.namespace/fopen.fail.cpp b/libcxx/test/libcxx/input.output/file.streams/c.files/no.global.filesystem.namespace/fopen.fail.cpp
index 04625da8822d7d82012c5a3903304fcbd1ca205b..1c2c329c278198c8628b441ec00ae6e2b5b82523 100644
--- a/libcxx/test/libcxx/input.output/file.streams/c.files/no.global.filesystem.namespace/fopen.fail.cpp
+++ b/libcxx/test/libcxx/input.output/file.streams/c.files/no.global.filesystem.namespace/fopen.fail.cpp
@@ -10,7 +10,9 @@
 
 #include <cstdio>
 
-int main() {
+int main(int, char**) {
     // fopen is not available on systems without a global filesystem namespace.
     std::fopen("", "");
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/input.output/file.streams/c.files/no.global.filesystem.namespace/rename.fail.cpp b/libcxx/test/libcxx/input.output/file.streams/c.files/no.global.filesystem.namespace/rename.fail.cpp
index 02c9f1fb81aaefcbec25996c9e32f45cc9f64249..61ef15d17155f09e3f5cfa2a01d9d5981a39f8a5 100644
--- a/libcxx/test/libcxx/input.output/file.streams/c.files/no.global.filesystem.namespace/rename.fail.cpp
+++ b/libcxx/test/libcxx/input.output/file.streams/c.files/no.global.filesystem.namespace/rename.fail.cpp
@@ -10,7 +10,9 @@
 
 #include <cstdio>
 
-int main() {
+int main(int, char**) {
     // rename is not available on systems without a global filesystem namespace.
     std::rename("", "");
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/input.output/file.streams/c.files/version_ccstdio.pass.cpp b/libcxx/test/libcxx/input.output/file.streams/c.files/version_ccstdio.pass.cpp
index 0325a45e3ccad5b73f0f01ed6c37ef857193f11b..d8ff6a7ac0a4851ae81fd604f57b44fe3cc1a648 100644
--- a/libcxx/test/libcxx/input.output/file.streams/c.files/version_ccstdio.pass.cpp
+++ b/libcxx/test/libcxx/input.output/file.streams/c.files/version_ccstdio.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/input.output/file.streams/c.files/version_cinttypes.pass.cpp b/libcxx/test/libcxx/input.output/file.streams/c.files/version_cinttypes.pass.cpp
index 3104bc9aab30b7061ecc3df4bc2b47d81ed81d03..23cecf9cbef15f8b96d71891bf4c31fc5d2a604d 100644
--- a/libcxx/test/libcxx/input.output/file.streams/c.files/version_cinttypes.pass.cpp
+++ b/libcxx/test/libcxx/input.output/file.streams/c.files/version_cinttypes.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/input.output/file.streams/fstreams/filebuf/traits_mismatch.fail.cpp b/libcxx/test/libcxx/input.output/file.streams/fstreams/filebuf/traits_mismatch.fail.cpp
index d7e80827a54a2250e7498d277d7469afc23f09b6..91b678d1d2d6964810f51699d429e5d41ff9e99e 100644
--- a/libcxx/test/libcxx/input.output/file.streams/fstreams/filebuf/traits_mismatch.fail.cpp
+++ b/libcxx/test/libcxx/input.output/file.streams/fstreams/filebuf/traits_mismatch.fail.cpp
@@ -15,9 +15,11 @@
 
 #include <fstream>
 
-int main()
+int main(int, char**)
 {
 	std::basic_filebuf<char, std::char_traits<wchar_t> > f;
 //  expected-error-re@streambuf:* {{static_assert failed{{.*}} "traits_type::char_type must be the same type as CharT"}}
+
+  return 0;
 }
 
diff --git a/libcxx/test/libcxx/input.output/file.streams/fstreams/fstream.close.pass.cpp b/libcxx/test/libcxx/input.output/file.streams/fstreams/fstream.close.pass.cpp
index ff93466da6f97efccdb24a5e34ab84eda18f9b43..6af87698156520a4278e20cf9a52ebb32187aa83 100644
--- a/libcxx/test/libcxx/input.output/file.streams/fstreams/fstream.close.pass.cpp
+++ b/libcxx/test/libcxx/input.output/file.streams/fstreams/fstream.close.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include "platform_support.h"
 
-int main()
+int main(int, char**)
 {
     std::string temp = get_temp_file_name();
 
@@ -31,4 +31,6 @@ int main()
     assert(!ofs.good());
 
     std::remove(temp.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/input.output/file.streams/fstreams/fstream.cons/wchar_pointer.pass.cpp b/libcxx/test/libcxx/input.output/file.streams/fstreams/fstream.cons/wchar_pointer.pass.cpp
index 70621cf79da8f0243aa4c85bdacfefd16a24d411..19442da51ac6534075cb65f2bf6b3f2eb91c3c74 100644
--- a/libcxx/test/libcxx/input.output/file.streams/fstreams/fstream.cons/wchar_pointer.pass.cpp
+++ b/libcxx/test/libcxx/input.output/file.streams/fstreams/fstream.cons/wchar_pointer.pass.cpp
@@ -17,7 +17,7 @@
 #include <cassert>
 #include "platform_support.h"
 
-int main()
+int main(int, char**)
 {
 #ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
     std::wstring temp = get_wide_temp_file_name();
@@ -42,4 +42,6 @@ int main()
     }
     _wremove(temp.c_str());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/input.output/file.streams/fstreams/fstream.members/open_wchar_pointer.pass.cpp b/libcxx/test/libcxx/input.output/file.streams/fstreams/fstream.members/open_wchar_pointer.pass.cpp
index e7b787592564da67e707882405f97c1d2b4ac9f0..0dead68c97dac5521e73313a5125485f255aeff0 100644
--- a/libcxx/test/libcxx/input.output/file.streams/fstreams/fstream.members/open_wchar_pointer.pass.cpp
+++ b/libcxx/test/libcxx/input.output/file.streams/fstreams/fstream.members/open_wchar_pointer.pass.cpp
@@ -17,7 +17,7 @@
 #include <cassert>
 #include "platform_support.h"
 
-int main()
+int main(int, char**)
 {
 #ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
     std::wstring temp = get_wide_temp_file_name();
@@ -48,4 +48,6 @@ int main()
     }
     _wremove(temp.c_str());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/input.output/file.streams/fstreams/ifstream.cons/wchar_pointer.pass.cpp b/libcxx/test/libcxx/input.output/file.streams/fstreams/ifstream.cons/wchar_pointer.pass.cpp
index 793b0f6b8403d260b4398d90895f0873b99c8342..178c7d69a43ecb65342ad31270ece1ee6e246ee2 100644
--- a/libcxx/test/libcxx/input.output/file.streams/fstreams/ifstream.cons/wchar_pointer.pass.cpp
+++ b/libcxx/test/libcxx/input.output/file.streams/fstreams/ifstream.cons/wchar_pointer.pass.cpp
@@ -16,7 +16,7 @@
 #include <fstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
 #ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
     {
@@ -38,4 +38,6 @@ int main()
     // test/libcxx/input.output/file.streams/fstreams/ofstream.cons/wchar_pointer.pass.cpp
     // which creates writable files.
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/input.output/file.streams/fstreams/ifstream.members/open_wchar_pointer.pass.cpp b/libcxx/test/libcxx/input.output/file.streams/fstreams/ifstream.members/open_wchar_pointer.pass.cpp
index effbe1e9b1e29b0b1d5839a9d1bd4fb4c02ff41e..2e8b3620ed1ae48119b66fb750e993d27a308dd7 100644
--- a/libcxx/test/libcxx/input.output/file.streams/fstreams/ifstream.members/open_wchar_pointer.pass.cpp
+++ b/libcxx/test/libcxx/input.output/file.streams/fstreams/ifstream.members/open_wchar_pointer.pass.cpp
@@ -16,7 +16,7 @@
 #include <fstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
 #ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
     {
@@ -44,4 +44,6 @@ int main()
         assert(c == L'r');
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/input.output/file.streams/fstreams/ofstream.cons/wchar_pointer.pass.cpp b/libcxx/test/libcxx/input.output/file.streams/fstreams/ofstream.cons/wchar_pointer.pass.cpp
index 453caa38487359ee4080d72eb2915866666d9715..7d6304cc9c9457d858b6927acbcc7b32b49c1971 100644
--- a/libcxx/test/libcxx/input.output/file.streams/fstreams/ofstream.cons/wchar_pointer.pass.cpp
+++ b/libcxx/test/libcxx/input.output/file.streams/fstreams/ofstream.cons/wchar_pointer.pass.cpp
@@ -17,7 +17,7 @@
 #include <cassert>
 #include "platform_support.h"
 
-int main()
+int main(int, char**)
 {
 #ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
     std::wstring temp = get_wide_temp_file_name();
@@ -56,4 +56,6 @@ int main()
     }
     _wremove(temp.c_str());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/input.output/file.streams/fstreams/ofstream.members/open_wchar_pointer.pass.cpp b/libcxx/test/libcxx/input.output/file.streams/fstreams/ofstream.members/open_wchar_pointer.pass.cpp
index 4a847fab3d8af41c8c13f403fec9caa6c1dcc165..58f08b86533ef06bffad2bc3ba9e2c5667c6da08 100644
--- a/libcxx/test/libcxx/input.output/file.streams/fstreams/ofstream.members/open_wchar_pointer.pass.cpp
+++ b/libcxx/test/libcxx/input.output/file.streams/fstreams/ofstream.members/open_wchar_pointer.pass.cpp
@@ -17,7 +17,7 @@
 #include <cassert>
 #include "platform_support.h"
 
-int main()
+int main(int, char**)
 {
 #ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
     std::wstring temp = get_wide_temp_file_name();
@@ -56,4 +56,6 @@ int main()
     }
     _wremove(temp.c_str());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/input.output/file.streams/fstreams/traits_mismatch.fail.cpp b/libcxx/test/libcxx/input.output/file.streams/fstreams/traits_mismatch.fail.cpp
index 19dd2ac711ba5794d91543f6de91f4a3fe43eabd..432cfccac4695cf5bdc28144f8e6de04bcbd5ef9 100644
--- a/libcxx/test/libcxx/input.output/file.streams/fstreams/traits_mismatch.fail.cpp
+++ b/libcxx/test/libcxx/input.output/file.streams/fstreams/traits_mismatch.fail.cpp
@@ -15,7 +15,7 @@
 
 #include <fstream>
 
-int main()
+int main(int, char**)
 {
 	std::basic_fstream<char, std::char_traits<wchar_t> > f;
 //  expected-error-re@ios:* {{static_assert failed{{.*}} "traits_type::char_type must be the same type as CharT"}}
@@ -25,5 +25,7 @@ int main()
 // exception specifications for types which are already invalid for one reason or another.
 // For now we tolerate this diagnostic.
 // expected-error@ostream:* 0-1 {{exception specification of overriding function is more lax than base version}}
+
+  return 0;
 }
 
diff --git a/libcxx/test/libcxx/input.output/file.streams/fstreams/version.pass.cpp b/libcxx/test/libcxx/input.output/file.streams/fstreams/version.pass.cpp
index bc578f1b617d8f4f010c95060c87797d6f6de6c9..51532408873f77572eed9a46ec55474a20d08ec8 100644
--- a/libcxx/test/libcxx/input.output/file.streams/fstreams/version.pass.cpp
+++ b/libcxx/test/libcxx/input.output/file.streams/fstreams/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/input.output/filesystems/class.path/path.itr/iterator_db.pass.cpp b/libcxx/test/libcxx/input.output/filesystems/class.path/path.itr/iterator_db.pass.cpp
index 0a9fdb54f381811af08fa4d6b993b31c93a5555c..396e4ff245cb935d244fd599d4c1c802437b32e3 100644
--- a/libcxx/test/libcxx/input.output/filesystems/class.path/path.itr/iterator_db.pass.cpp
+++ b/libcxx/test/libcxx/input.output/filesystems/class.path/path.itr/iterator_db.pass.cpp
@@ -26,7 +26,7 @@
 #include "test_macros.h"
 #include "filesystem_test_helper.hpp"
 
-int main() {
+int main(int, char**) {
   using namespace fs;
   using ExType = std::__libcpp_debug_exception;
   // Test incrementing/decrementing a singular iterator
@@ -71,4 +71,6 @@ int main() {
       assert(false);
     } catch (ExType const&) {}
   }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/input.output/filesystems/class.path/path.itr/reverse_iterator_produces_diagnostic.fail.cpp b/libcxx/test/libcxx/input.output/filesystems/class.path/path.itr/reverse_iterator_produces_diagnostic.fail.cpp
index d32b7303ad72dbb4dc0d30a7359e62a8fba95600..5eb5cbdb39e1c2f6ce163f9a012b499bef6cb46a 100644
--- a/libcxx/test/libcxx/input.output/filesystems/class.path/path.itr/reverse_iterator_produces_diagnostic.fail.cpp
+++ b/libcxx/test/libcxx/input.output/filesystems/class.path/path.itr/reverse_iterator_produces_diagnostic.fail.cpp
@@ -16,7 +16,7 @@
 #include <iterator>
 
 
-int main() {
+int main(int, char**) {
   using namespace fs;
   using RIt = std::reverse_iterator<path::iterator>;
 
@@ -25,4 +25,6 @@ int main() {
     RIt r;
     ((void)r);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/input.output/filesystems/class.path/path.req/is_pathable.pass.cpp b/libcxx/test/libcxx/input.output/filesystems/class.path/path.req/is_pathable.pass.cpp
index 1cfa173da7c7095c6fdcd91d53790760064b2f16..a80f02e4ca6ab60fd8563b7ed3eed81103e8612e 100644
--- a/libcxx/test/libcxx/input.output/filesystems/class.path/path.req/is_pathable.pass.cpp
+++ b/libcxx/test/libcxx/input.output/filesystems/class.path/path.req/is_pathable.pass.cpp
@@ -95,9 +95,11 @@ struct MakeTestType {
   }
 };
 
-int main() {
+int main(int, char**) {
   MakeTestType<char>::Test();
   MakeTestType<wchar_t>::Test();
   MakeTestType<char16_t>::Test();
   MakeTestType<char32_t>::Test();
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/input.output/filesystems/convert_file_time.sh.cpp b/libcxx/test/libcxx/input.output/filesystems/convert_file_time.sh.cpp
index ac64dc7ab1797462e0f1b4c775d59df93a76001b..55cd659cc4d133dc84504fdadf1ef835c6a5b60b 100644
--- a/libcxx/test/libcxx/input.output/filesystems/convert_file_time.sh.cpp
+++ b/libcxx/test/libcxx/input.output/filesystems/convert_file_time.sh.cpp
@@ -277,7 +277,7 @@ struct TestClock {
 template <class IntType, class Period = std::micro>
 using TestFileTimeT = time_point<TestClock<duration<IntType, Period> > >;
 
-int main() {
+int main(int, char**) {
   { assert((test_case<file_time_type, time_t, struct timespec>::test())); }
   {
     assert((test_case<TestFileTimeT<int64_t>, int64_t,
@@ -303,4 +303,6 @@ int main() {
                       TestTimeSpec<int32_t, int32_t> >::test()));
   }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/input.output/filesystems/version.pass.cpp b/libcxx/test/libcxx/input.output/filesystems/version.pass.cpp
index b94e32cbc2fd7c535a6ce9923d238fe0c7aee411..b0f03174425d6d37cec469188b5b658be811eeff 100644
--- a/libcxx/test/libcxx/input.output/filesystems/version.pass.cpp
+++ b/libcxx/test/libcxx/input.output/filesystems/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/input.output/iostream.format/input.streams/traits_mismatch.fail.cpp b/libcxx/test/libcxx/input.output/iostream.format/input.streams/traits_mismatch.fail.cpp
index 5be4344ab71acf8f2c29efbaa1521e46fe833af5..32088497a71a663c8b23beb73ba80b61fe229399 100644
--- a/libcxx/test/libcxx/input.output/iostream.format/input.streams/traits_mismatch.fail.cpp
+++ b/libcxx/test/libcxx/input.output/iostream.format/input.streams/traits_mismatch.fail.cpp
@@ -21,8 +21,10 @@ struct test_istream
     : public std::basic_istream<char, std::char_traits<wchar_t> > {};
 
 
-int main()
+int main(int, char**)
 {
 //  expected-error-re@ios:* {{static_assert failed{{.*}} "traits_type::char_type must be the same type as CharT"}}
+
+  return 0;
 }
 
diff --git a/libcxx/test/libcxx/input.output/iostream.format/input.streams/version.pass.cpp b/libcxx/test/libcxx/input.output/iostream.format/input.streams/version.pass.cpp
index 65c48c11ba51c25662d52474885341c54d204c03..77ed7563bdaa63e237b19d134ae9e1cd858c77d9 100644
--- a/libcxx/test/libcxx/input.output/iostream.format/input.streams/version.pass.cpp
+++ b/libcxx/test/libcxx/input.output/iostream.format/input.streams/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/input.output/iostream.format/output.streams/traits_mismatch.fail.cpp b/libcxx/test/libcxx/input.output/iostream.format/output.streams/traits_mismatch.fail.cpp
index caa020f173c08e5c884de6118139eb06f574511c..8975097456bfb4256322c799854cb02cf498cd76 100644
--- a/libcxx/test/libcxx/input.output/iostream.format/output.streams/traits_mismatch.fail.cpp
+++ b/libcxx/test/libcxx/input.output/iostream.format/output.streams/traits_mismatch.fail.cpp
@@ -21,8 +21,10 @@ struct test_ostream
     : public std::basic_ostream<char, std::char_traits<wchar_t> > {};
 
 
-int main()
+int main(int, char**)
 {
 //  expected-error-re@ios:* {{static_assert failed{{.*}} "traits_type::char_type must be the same type as CharT"}}
+
+  return 0;
 }
 
diff --git a/libcxx/test/libcxx/input.output/iostream.format/output.streams/version.pass.cpp b/libcxx/test/libcxx/input.output/iostream.format/output.streams/version.pass.cpp
index f381fcffdef954e4da740f47f847ec1a28b35187..f16e9a079d012fd12ae015e99604d396403ea0b6 100644
--- a/libcxx/test/libcxx/input.output/iostream.format/output.streams/version.pass.cpp
+++ b/libcxx/test/libcxx/input.output/iostream.format/output.streams/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/input.output/iostream.format/std.manip/version.pass.cpp b/libcxx/test/libcxx/input.output/iostream.format/std.manip/version.pass.cpp
index 775eec29529abee8caa066ddf372e27fe651496c..498410ed106ffcf536bcf833efcb03a67806c2d9 100644
--- a/libcxx/test/libcxx/input.output/iostream.format/std.manip/version.pass.cpp
+++ b/libcxx/test/libcxx/input.output/iostream.format/std.manip/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/input.output/iostream.forward/version.pass.cpp b/libcxx/test/libcxx/input.output/iostream.forward/version.pass.cpp
index 509d7efdbddde551faf2cd54687cb4926bf6b655..70f1ec6626fb1d4489144bd7a51e78e65614a098 100644
--- a/libcxx/test/libcxx/input.output/iostream.forward/version.pass.cpp
+++ b/libcxx/test/libcxx/input.output/iostream.forward/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/input.output/iostream.objects/version.pass.cpp b/libcxx/test/libcxx/input.output/iostream.objects/version.pass.cpp
index f05cdfff7bbc18b70a75b2ab39e289c8b562a9bc..7081e5abf1618fd26afdc19f955e00512a1c7059 100644
--- a/libcxx/test/libcxx/input.output/iostream.objects/version.pass.cpp
+++ b/libcxx/test/libcxx/input.output/iostream.objects/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/input.output/iostreams.base/version.pass.cpp b/libcxx/test/libcxx/input.output/iostreams.base/version.pass.cpp
index 8090783e9667cad026828e904a0f4b67ec0fa2ba..4b873a92661f4cf1504e55fa6506c22fe03390e0 100644
--- a/libcxx/test/libcxx/input.output/iostreams.base/version.pass.cpp
+++ b/libcxx/test/libcxx/input.output/iostreams.base/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/input.output/stream.buffers/version.pass.cpp b/libcxx/test/libcxx/input.output/stream.buffers/version.pass.cpp
index 08cd627855a5eb642b5691868f2121993b1e7b1c..cc55444b55b79f63052295ecbe19cf45fe57ef4e 100644
--- a/libcxx/test/libcxx/input.output/stream.buffers/version.pass.cpp
+++ b/libcxx/test/libcxx/input.output/stream.buffers/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/input.output/string.streams/traits_mismatch.fail.cpp b/libcxx/test/libcxx/input.output/string.streams/traits_mismatch.fail.cpp
index 0eeb740aa28c7e3241ae38896f44781911787b3c..a046b34abf7ed31daa97c2da0ce7973634908705 100644
--- a/libcxx/test/libcxx/input.output/string.streams/traits_mismatch.fail.cpp
+++ b/libcxx/test/libcxx/input.output/string.streams/traits_mismatch.fail.cpp
@@ -16,10 +16,12 @@
 
 #include <sstream>
 
-int main()
+int main(int, char**)
 {
 	std::basic_stringbuf<char, std::char_traits<wchar_t> > sb;
 //  expected-error-re@streambuf:* {{static_assert failed{{.*}} "traits_type::char_type must be the same type as CharT"}}
 //  expected-error-re@string:* {{static_assert failed{{.*}} "traits_type::char_type must be the same type as CharT"}}
+
+  return 0;
 }
 
diff --git a/libcxx/test/libcxx/input.output/string.streams/version.pass.cpp b/libcxx/test/libcxx/input.output/string.streams/version.pass.cpp
index 6725d8509a0e9e999b2a67355bbc7d86a5e9fbd9..03beac77bca890ca0c9314479cb6269b5fe8e766 100644
--- a/libcxx/test/libcxx/input.output/string.streams/version.pass.cpp
+++ b/libcxx/test/libcxx/input.output/string.streams/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/iterators/failed.pass.cpp b/libcxx/test/libcxx/iterators/failed.pass.cpp
index b9bcb02500e9e4a3cde0434a4ebe55d60633decd..e44c15ebaa2d373f9c750716a71db0e907c6ec18 100644
--- a/libcxx/test/libcxx/iterators/failed.pass.cpp
+++ b/libcxx/test/libcxx/iterators/failed.pass.cpp
@@ -18,7 +18,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::ostreambuf_iterator<char> i(nullptr);
@@ -28,4 +28,6 @@ int main()
         std::ostreambuf_iterator<wchar_t> i(nullptr);
         assert(i.failed());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/iterators/trivial_iterators.pass.cpp b/libcxx/test/libcxx/iterators/trivial_iterators.pass.cpp
index 0a77befed7e672eb75d9374e4e78712f41f7c96e..0618731ce75a2dbd39d853ff5c3554448c5c8e91 100644
--- a/libcxx/test/libcxx/iterators/trivial_iterators.pass.cpp
+++ b/libcxx/test/libcxx/iterators/trivial_iterators.pass.cpp
@@ -90,7 +90,7 @@ operator!=(const my_input_iterator<T>& x, const my_input_iterator<U>& y)
 }
 
 
-int main()
+int main(int, char**)
 {
 //  basic tests
     static_assert(( std::__libcpp_is_trivial_iterator<char *>::value), "");
@@ -184,4 +184,6 @@ int main()
     static_assert(( std::__libcpp_is_trivial_iterator<std::initializer_list<char>::const_iterator>        ::value), "");
 #endif
 
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/iterators/version.pass.cpp b/libcxx/test/libcxx/iterators/version.pass.cpp
index 9fe0a9e2eb9dd071e6750c09070b7c148da8f5b5..16668898a4b4e01f24abc524970c38d90dbde8b4 100644
--- a/libcxx/test/libcxx/iterators/version.pass.cpp
+++ b/libcxx/test/libcxx/iterators/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/language.support/cmp/version.pass.cpp b/libcxx/test/libcxx/language.support/cmp/version.pass.cpp
index ae3a573d71a1665229b74ef2ccafd71a514173be..9d2ae8ac113569c675f663424d32bd2c4fa8c72f 100644
--- a/libcxx/test/libcxx/language.support/cmp/version.pass.cpp
+++ b/libcxx/test/libcxx/language.support/cmp/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/language.support/cstdint/version.pass.cpp b/libcxx/test/libcxx/language.support/cstdint/version.pass.cpp
index 31822ac7ad464434eee3d3661c5b8435aa589004..9f11f15d118aea694da8b89b50433e798d0e70cf 100644
--- a/libcxx/test/libcxx/language.support/cstdint/version.pass.cpp
+++ b/libcxx/test/libcxx/language.support/cstdint/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/language.support/cxa_deleted_virtual.pass.cpp b/libcxx/test/libcxx/language.support/cxa_deleted_virtual.pass.cpp
index 0439819701c49cca2c44490e5f69d1519e927719..b5171a39e1075dc8f4f5159c76e490115dae874f 100644
--- a/libcxx/test/libcxx/language.support/cxa_deleted_virtual.pass.cpp
+++ b/libcxx/test/libcxx/language.support/cxa_deleted_virtual.pass.cpp
@@ -21,7 +21,9 @@
 // XFAIL: with_system_cxx_lib=macosx10.7
 
 struct S { virtual void f() = delete; virtual ~S() {} };
-int main() {
+int main(int, char**) {
   S *s = new S;
   delete s;
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/language.support/has_c11_features.pass.cpp b/libcxx/test/libcxx/language.support/has_c11_features.pass.cpp
index 1bba504cd9420bc902b25a8eb7c441db9275c850..7abdbc1c8619fb9430490c584ab3dc313f743194 100644
--- a/libcxx/test/libcxx/language.support/has_c11_features.pass.cpp
+++ b/libcxx/test/libcxx/language.support/has_c11_features.pass.cpp
@@ -28,4 +28,6 @@
 # endif
 #endif
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/libcxx/language.support/support.dynamic/libcpp_deallocate.sh.cpp b/libcxx/test/libcxx/language.support/support.dynamic/libcpp_deallocate.sh.cpp
index be2e69e6893d504af4f821f963b6ac4cf88f5379..04ba34ca0eab9c16636b4e678ae62bd72b4f4e7f 100644
--- a/libcxx/test/libcxx/language.support/support.dynamic/libcpp_deallocate.sh.cpp
+++ b/libcxx/test/libcxx/language.support/support.dynamic/libcpp_deallocate.sh.cpp
@@ -253,7 +253,9 @@ void test_allocator_and_new_match() {
 #endif
 }
 
-int main() {
+int main(int, char**) {
   test_libcpp_dealloc();
   test_allocator_and_new_match();
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/language.support/support.dynamic/new_faligned_allocation.sh.cpp b/libcxx/test/libcxx/language.support/support.dynamic/new_faligned_allocation.sh.cpp
index 65943139f2b401e8a6089f350c8b1190957f3d06..f3db56478426853cc45d149b632130f2f66a8949 100644
--- a/libcxx/test/libcxx/language.support/support.dynamic/new_faligned_allocation.sh.cpp
+++ b/libcxx/test/libcxx/language.support/support.dynamic/new_faligned_allocation.sh.cpp
@@ -36,7 +36,7 @@
 
 #include "test_macros.h"
 
-int main() {
+int main(int, char**) {
   {
     static_assert(std::is_enum<std::align_val_t>::value, "");
     typedef std::underlying_type<std::align_val_t>::type UT;
@@ -88,4 +88,6 @@ int main() {
     assert(typeid(std::align_val_t).name() == std::string("St11align_val_t"));
   }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/language.support/support.dynamic/version.pass.cpp b/libcxx/test/libcxx/language.support/support.dynamic/version.pass.cpp
index a3ca4f61767327d5ff95081dcdb0146bb56111a7..c3f542ca8407d022bd53791ec354b3d1a2cf95d3 100644
--- a/libcxx/test/libcxx/language.support/support.dynamic/version.pass.cpp
+++ b/libcxx/test/libcxx/language.support/support.dynamic/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/language.support/support.exception/version.pass.cpp b/libcxx/test/libcxx/language.support/support.exception/version.pass.cpp
index 1161e67d0c1dfce19658a78102530ede967609cb..495a8cde9697d3dc021b1f392064420744db63a8 100644
--- a/libcxx/test/libcxx/language.support/support.exception/version.pass.cpp
+++ b/libcxx/test/libcxx/language.support/support.exception/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/language.support/support.initlist/version.pass.cpp b/libcxx/test/libcxx/language.support/support.initlist/version.pass.cpp
index 9b11ce1c66c4e6a943b258ff30ed81eb6085dae4..6f42987b16e03f23ca9901cc5cc9c82d66e44d0e 100644
--- a/libcxx/test/libcxx/language.support/support.initlist/version.pass.cpp
+++ b/libcxx/test/libcxx/language.support/support.initlist/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/language.support/support.limits/c.limits/version_cfloat.pass.cpp b/libcxx/test/libcxx/language.support/support.limits/c.limits/version_cfloat.pass.cpp
index ee03d9ef0cf6d634fd518ebe34abcec2314c05fc..baa925f7d05fb78a217e846e59630da06e1adc14 100644
--- a/libcxx/test/libcxx/language.support/support.limits/c.limits/version_cfloat.pass.cpp
+++ b/libcxx/test/libcxx/language.support/support.limits/c.limits/version_cfloat.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/language.support/support.limits/c.limits/version_climits.pass.cpp b/libcxx/test/libcxx/language.support/support.limits/c.limits/version_climits.pass.cpp
index 94fd729c49537a318063ad771ea00cce43a2e2ce..208b16ed78072b9dd0059c5abaa7805c796093f3 100644
--- a/libcxx/test/libcxx/language.support/support.limits/c.limits/version_climits.pass.cpp
+++ b/libcxx/test/libcxx/language.support/support.limits/c.limits/version_climits.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/language.support/support.limits/limits/version.pass.cpp b/libcxx/test/libcxx/language.support/support.limits/limits/version.pass.cpp
index 4d9ba389290320a9038c433814824f1b600a24b2..a17643bc45fad8cd97d506c3217395c06aa97d07 100644
--- a/libcxx/test/libcxx/language.support/support.limits/limits/version.pass.cpp
+++ b/libcxx/test/libcxx/language.support/support.limits/limits/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/language.support/support.limits/version.pass.cpp b/libcxx/test/libcxx/language.support/support.limits/version.pass.cpp
index e884d285a2b2caa5d9fd7ee8dc7347bfeef8466a..4277147f6e19113842a7c404df89688a545343f0 100644
--- a/libcxx/test/libcxx/language.support/support.limits/version.pass.cpp
+++ b/libcxx/test/libcxx/language.support/support.limits/version.pass.cpp
@@ -14,6 +14,8 @@
 #error "_LIBCPP_VERSION must be defined after including <version>"
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/language.support/support.rtti/version.pass.cpp b/libcxx/test/libcxx/language.support/support.rtti/version.pass.cpp
index 84d74db3d7ce1536c1f4bc07c614455031d46c8a..3d21c8487b9c175413dc3b2a59f72c3b65299150 100644
--- a/libcxx/test/libcxx/language.support/support.rtti/version.pass.cpp
+++ b/libcxx/test/libcxx/language.support/support.rtti/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/language.support/support.runtime/version_csetjmp.pass.cpp b/libcxx/test/libcxx/language.support/support.runtime/version_csetjmp.pass.cpp
index 261dd3cde0e3c6c681fbf5d44f71141240da8eeb..9bceaf8238f3ff82c2a00a08d5856e49d6194e18 100644
--- a/libcxx/test/libcxx/language.support/support.runtime/version_csetjmp.pass.cpp
+++ b/libcxx/test/libcxx/language.support/support.runtime/version_csetjmp.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/language.support/support.runtime/version_csignal.pass.cpp b/libcxx/test/libcxx/language.support/support.runtime/version_csignal.pass.cpp
index a602675ce294220044a55851622af5f74218e0df..b93fb0d172c71540b57a80e0237fe8733dc43744 100644
--- a/libcxx/test/libcxx/language.support/support.runtime/version_csignal.pass.cpp
+++ b/libcxx/test/libcxx/language.support/support.runtime/version_csignal.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/language.support/support.runtime/version_cstdarg.pass.cpp b/libcxx/test/libcxx/language.support/support.runtime/version_cstdarg.pass.cpp
index 1dde2b656aeb3c9d88bf94dfd8fb091d4562dcd5..0ddd98b52c29d33f4c636a75dec22b46f9e4cf52 100644
--- a/libcxx/test/libcxx/language.support/support.runtime/version_cstdarg.pass.cpp
+++ b/libcxx/test/libcxx/language.support/support.runtime/version_cstdarg.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/language.support/support.runtime/version_cstdbool.pass.cpp b/libcxx/test/libcxx/language.support/support.runtime/version_cstdbool.pass.cpp
index 219efa15367f89b5bb5943663e5a2d7372459709..85f1fb34d83b541515beab1a11ebd0376d1d30f2 100644
--- a/libcxx/test/libcxx/language.support/support.runtime/version_cstdbool.pass.cpp
+++ b/libcxx/test/libcxx/language.support/support.runtime/version_cstdbool.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/language.support/support.runtime/version_cstdlib.pass.cpp b/libcxx/test/libcxx/language.support/support.runtime/version_cstdlib.pass.cpp
index 431e3d9a9d27f1ea3ba72cf91e409b8004ae2710..9a5a02fb882cb64f5bf4f8888296a7560f376b34 100644
--- a/libcxx/test/libcxx/language.support/support.runtime/version_cstdlib.pass.cpp
+++ b/libcxx/test/libcxx/language.support/support.runtime/version_cstdlib.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/language.support/support.runtime/version_ctime.pass.cpp b/libcxx/test/libcxx/language.support/support.runtime/version_ctime.pass.cpp
index d38788602d32989f53e44f6601ac6b5ad2e3643b..bc2d039b3d024c7107efc610a94f184e20531860 100644
--- a/libcxx/test/libcxx/language.support/support.runtime/version_ctime.pass.cpp
+++ b/libcxx/test/libcxx/language.support/support.runtime/version_ctime.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/language.support/support.types/version.pass.cpp b/libcxx/test/libcxx/language.support/support.types/version.pass.cpp
index 8c05c656301a4211c62541eb83134f00f3366bfa..5dd755c0066ca70025dd6c6c21d41e7508ee3bcf 100644
--- a/libcxx/test/libcxx/language.support/support.types/version.pass.cpp
+++ b/libcxx/test/libcxx/language.support/support.types/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/libcpp_alignof.pass.cpp b/libcxx/test/libcxx/libcpp_alignof.pass.cpp
index ab64889b5f26ba4ed18877a8cab19bdcb423d9a1..0f67210847a8718db4768790ebcb8a09229fbcc9 100644
--- a/libcxx/test/libcxx/libcpp_alignof.pass.cpp
+++ b/libcxx/test/libcxx/libcpp_alignof.pass.cpp
@@ -28,9 +28,10 @@ void test() {
 #endif
 }
 
-int main() {
+int main(int, char**) {
   test<int>();
   test<long long>();
   test<double>();
   test<long double>();
+  return 0;
 }
diff --git a/libcxx/test/libcxx/libcpp_version.pass.cpp b/libcxx/test/libcxx/libcpp_version.pass.cpp
index 9d7e6dce111d514866346c81c99364d065980a23..a2d18c3bb3f76e9149b680ec56efdfc17a27a4bd 100644
--- a/libcxx/test/libcxx/libcpp_version.pass.cpp
+++ b/libcxx/test/libcxx/libcpp_version.pass.cpp
@@ -22,6 +22,8 @@ static const int libcpp_version =
 static_assert(_LIBCPP_VERSION == libcpp_version,
               "_LIBCPP_VERSION doesn't match __libcpp_version");
 
-int main() {
+int main(int, char**) {
 
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/localization/c.locales/version.pass.cpp b/libcxx/test/libcxx/localization/c.locales/version.pass.cpp
index 5a4f1064cc2ea7422713d3039e82e776be509619..2dfc76dd909c444e73e7e4e14c9455be768e16ee 100644
--- a/libcxx/test/libcxx/localization/c.locales/version.pass.cpp
+++ b/libcxx/test/libcxx/localization/c.locales/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/localization/locale.categories/__scan_keyword.pass.cpp b/libcxx/test/libcxx/localization/locale.categories/__scan_keyword.pass.cpp
index 6da1aa5758e348606278a8ecd4c4ed02b6056213..b85bd8a580f5914bd783fc5ab735a985dcf618fb 100644
--- a/libcxx/test/libcxx/localization/locale.categories/__scan_keyword.pass.cpp
+++ b/libcxx/test/libcxx/localization/locale.categories/__scan_keyword.pass.cpp
@@ -38,7 +38,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::ctype<char>& ct = std::use_facet<std::ctype<char> >(std::locale::classic());
     std::ios_base::iostate err = std::ios_base::goodbit;
@@ -114,4 +114,6 @@ int main()
         assert(in == input+3);
         assert(err == std::ios_base::goodbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/localization/locale.stdcvt/version.pass.cpp b/libcxx/test/libcxx/localization/locale.stdcvt/version.pass.cpp
index 1e346afb6c04d4adfa462690ed6b4455a4fe3f08..738ab5e41f42b4797bc8e279b7e711716ed549f4 100644
--- a/libcxx/test/libcxx/localization/locale.stdcvt/version.pass.cpp
+++ b/libcxx/test/libcxx/localization/locale.stdcvt/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/localization/locales/locale.convenience/conversions/conversions.string/ctor_move.pass.cpp b/libcxx/test/libcxx/localization/locales/locale.convenience/conversions/conversions.string/ctor_move.pass.cpp
index 996f6bdc60a71ae193f8c15b409bb095c98ef43c..3aac6f532797a62028691a099e0d65343737a392 100644
--- a/libcxx/test/libcxx/localization/locales/locale.convenience/conversions/conversions.string/ctor_move.pass.cpp
+++ b/libcxx/test/libcxx/localization/locales/locale.convenience/conversions/conversions.string/ctor_move.pass.cpp
@@ -21,7 +21,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::codecvt_utf8<wchar_t> Codecvt;
     typedef std::wstring_convert<Codecvt> Myconv;
@@ -34,4 +34,6 @@ int main()
     // move construct a new converter and make sure the state is the same.
     Myconv myconv2(std::move(myconv));
     assert(myconv2.converted() == old_converted);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/localization/locales/locale/locale.types/locale.facet/facet.pass.cpp b/libcxx/test/libcxx/localization/locales/locale/locale.types/locale.facet/facet.pass.cpp
index 668cb55c677fdb4a43e26a6716c4586889f8b382..7be14d6be2bd80f1639370d9b9e439d84bc86bf3 100644
--- a/libcxx/test/libcxx/localization/locales/locale/locale.types/locale.facet/facet.pass.cpp
+++ b/libcxx/test/libcxx/localization/locales/locale/locale.types/locale.facet/facet.pass.cpp
@@ -35,7 +35,7 @@ struct my_facet
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     my_facet* f = new my_facet;
     f->__add_shared();
@@ -49,4 +49,6 @@ int main()
     assert(my_facet::count == 1);
     f->__release_shared();
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/localization/locales/locale/locale.types/locale.id/id.pass.cpp b/libcxx/test/libcxx/localization/locales/locale/locale.types/locale.id/id.pass.cpp
index 6844a0ad0b4c86fb876e6ab177a6a6cb1bdd09d4..758d7f8b81a109909f95088422fd2ce6fca32e07 100644
--- a/libcxx/test/libcxx/localization/locales/locale/locale.types/locale.id/id.pass.cpp
+++ b/libcxx/test/libcxx/localization/locales/locale/locale.types/locale.id/id.pass.cpp
@@ -25,7 +25,7 @@ std::locale::id id0;
 std::locale::id id2;
 std::locale::id id1;
 
-int main()
+int main(int, char**)
 {
     long id = id0.__get();
     assert(id0.__get() == id+0);
@@ -46,4 +46,6 @@ int main()
     assert(id2.__get() == id+2);
     assert(id2.__get() == id+2);
     assert(id2.__get() == id+2);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/localization/version.pass.cpp b/libcxx/test/libcxx/localization/version.pass.cpp
index 8b73ba58965992fe2212aa6a89f9b64cc15688ed..1d1294593d27227b03cfed068381ed6d6466d2a8 100644
--- a/libcxx/test/libcxx/localization/version.pass.cpp
+++ b/libcxx/test/libcxx/localization/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/memory/aligned_allocation_macro.pass.cpp b/libcxx/test/libcxx/memory/aligned_allocation_macro.pass.cpp
index b4aad040cf454f8cef67229478549ddcc11ddc65..7099eed2e0fbba6f06394f500984b31035e4b943 100644
--- a/libcxx/test/libcxx/memory/aligned_allocation_macro.pass.cpp
+++ b/libcxx/test/libcxx/memory/aligned_allocation_macro.pass.cpp
@@ -27,4 +27,6 @@
 #   error "libc++ should have aligned allocation in C++17 and up when targeting a platform that supports it"
 #endif
 
-int main() { }
+int main(int, char**) { 
+  return 0;
+}
diff --git a/libcxx/test/libcxx/memory/is_allocator.pass.cpp b/libcxx/test/libcxx/memory/is_allocator.pass.cpp
index d0f3e9c27d09c09ac078e37aee77ce0f848e5e18..d62a91f7d62acfedab82f2b29fd631e48eb53c66 100644
--- a/libcxx/test/libcxx/memory/is_allocator.pass.cpp
+++ b/libcxx/test/libcxx/memory/is_allocator.pass.cpp
@@ -32,10 +32,12 @@ void test_allocators()
 }
 
 
-int main()
+int main(int, char**)
 {
 //	test_allocators<void>();
 	test_allocators<char>();
 	test_allocators<int>();
 	test_allocators<std::string>();
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/modules/cinttypes_exports.sh.cpp b/libcxx/test/libcxx/modules/cinttypes_exports.sh.cpp
index 6e6c515e12e6e5c113da54aa3a6eb9e9dc7ebead..a24aafdcc737f6811d4df313aed8a8cf96fbb54e 100644
--- a/libcxx/test/libcxx/modules/cinttypes_exports.sh.cpp
+++ b/libcxx/test/libcxx/modules/cinttypes_exports.sh.cpp
@@ -18,7 +18,9 @@
 
 #include <cinttypes>
 
-int main() {
+int main(int, char**) {
   int8_t x; ((void)x);
   std::int8_t y; ((void)y);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/modules/clocale_exports.sh.cpp b/libcxx/test/libcxx/modules/clocale_exports.sh.cpp
index 480308c1e500666dc4163747c5224bc03ad5c4ae..3225155ca3685e06518d40cdd8522347264d5bbc 100644
--- a/libcxx/test/libcxx/modules/clocale_exports.sh.cpp
+++ b/libcxx/test/libcxx/modules/clocale_exports.sh.cpp
@@ -19,9 +19,11 @@
 
 #define TEST(...) do { using T = decltype( __VA_ARGS__ ); } while(false)
 
-int main() {
+int main(int, char**) {
   std::lconv l; ((void)l);
 
   TEST(std::setlocale(0, ""));
   TEST(std::localeconv());
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/modules/cstdint_exports.sh.cpp b/libcxx/test/libcxx/modules/cstdint_exports.sh.cpp
index 8ecb15c5cdc444c34c3db0ee45b09e163bca473e..315d9ac17b916d625db161424fb6a0146952b9a4 100644
--- a/libcxx/test/libcxx/modules/cstdint_exports.sh.cpp
+++ b/libcxx/test/libcxx/modules/cstdint_exports.sh.cpp
@@ -18,7 +18,9 @@
 
 #include <cstdint>
 
-int main() {
+int main(int, char**) {
   int8_t x; ((void)x);
   std::int8_t y; ((void)y);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/modules/inttypes_h_exports.sh.cpp b/libcxx/test/libcxx/modules/inttypes_h_exports.sh.cpp
index a51608c67eea837fea651eba7263118dae778e36..4cbb1d5742064ea2d4165a43d9ac9b2c17c4a0f1 100644
--- a/libcxx/test/libcxx/modules/inttypes_h_exports.sh.cpp
+++ b/libcxx/test/libcxx/modules/inttypes_h_exports.sh.cpp
@@ -18,6 +18,8 @@
 
 #include <inttypes.h>
 
-int main() {
+int main(int, char**) {
   int8_t x; ((void)x);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/modules/stdint_h_exports.sh.cpp b/libcxx/test/libcxx/modules/stdint_h_exports.sh.cpp
index 584a46515a7e6017a0b79d1381958a2d7f86a3de..5b35ba30ca6d5dfdd25a376ffe5581c1cef53dc4 100644
--- a/libcxx/test/libcxx/modules/stdint_h_exports.sh.cpp
+++ b/libcxx/test/libcxx/modules/stdint_h_exports.sh.cpp
@@ -14,6 +14,8 @@
 
 #include <stdint.h>
 
-int main() {
+int main(int, char**) {
   int8_t x; ((void)x);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/numerics/c.math/constexpr-fns.pass.cpp b/libcxx/test/libcxx/numerics/c.math/constexpr-fns.pass.cpp
index b15467cfd53c28bd1434a607cf842a66a73e9fc5..330b3a134f7b290967b4e8335c5bad270eeefa86 100644
--- a/libcxx/test/libcxx/numerics/c.math/constexpr-fns.pass.cpp
+++ b/libcxx/test/libcxx/numerics/c.math/constexpr-fns.pass.cpp
@@ -26,6 +26,8 @@ static_assert(std::__libcpp_isnan_or_builtin(0.) == false, "");
 static_assert(std::__libcpp_isinf_or_builtin(0.0) == false, "");
 static_assert(std::__libcpp_isfinite_or_builtin(0.0) == true, "");
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/numerics/c.math/ctgmath.pass.cpp b/libcxx/test/libcxx/numerics/c.math/ctgmath.pass.cpp
index 3b701579538bafd0ecc0364308b65c591e7289ce..81eac056bef66d0a3113b3fc78e684b9a9ac9b98 100644
--- a/libcxx/test/libcxx/numerics/c.math/ctgmath.pass.cpp
+++ b/libcxx/test/libcxx/numerics/c.math/ctgmath.pass.cpp
@@ -14,10 +14,12 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
     std::complex<double> cd;
     ((void)cd);
     double x = std::sin(0);
     ((void)x);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/numerics/c.math/fdelayed-template-parsing.sh.cpp b/libcxx/test/libcxx/numerics/c.math/fdelayed-template-parsing.sh.cpp
index 6007268b2fff8194c36f0977667c33fad919585c..37d09a8796f9d8cfe7ce9a30852fe85af4562915 100644
--- a/libcxx/test/libcxx/numerics/c.math/fdelayed-template-parsing.sh.cpp
+++ b/libcxx/test/libcxx/numerics/c.math/fdelayed-template-parsing.sh.cpp
@@ -18,10 +18,12 @@
 
 #include "test_macros.h"
 
-int main() {
+int main(int, char**) {
   assert(std::isfinite(1.0));
   assert(!std::isinf(1.0));
   assert(!std::isnan(1.0));
+
+  return 0;
 }
 
 using namespace std;
diff --git a/libcxx/test/libcxx/numerics/c.math/tgmath_h.pass.cpp b/libcxx/test/libcxx/numerics/c.math/tgmath_h.pass.cpp
index 3c2388992c7cbf1d027aa9bf685e36c383bcba9d..d3cd15ca0283d5f4da183620ed925da597336514 100644
--- a/libcxx/test/libcxx/numerics/c.math/tgmath_h.pass.cpp
+++ b/libcxx/test/libcxx/numerics/c.math/tgmath_h.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/numerics/c.math/version_cmath.pass.cpp b/libcxx/test/libcxx/numerics/c.math/version_cmath.pass.cpp
index b11a6a2e8ff12f1474916a9fc32159d8ede0b312..1b4ab9a6d8ea445bddf7c61f8f5c930a2b0a6b2c 100644
--- a/libcxx/test/libcxx/numerics/c.math/version_cmath.pass.cpp
+++ b/libcxx/test/libcxx/numerics/c.math/version_cmath.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/numerics/cfenv/version.pass.cpp b/libcxx/test/libcxx/numerics/cfenv/version.pass.cpp
index 8b523916ab8001c3be44b281e9b603dc6a8ee3dd..9ce5b9c4cb230e1b3c10126b910dbe90acc1ff65 100644
--- a/libcxx/test/libcxx/numerics/cfenv/version.pass.cpp
+++ b/libcxx/test/libcxx/numerics/cfenv/version.pass.cpp
@@ -16,6 +16,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/numerics/complex.number/__sqr.pass.cpp b/libcxx/test/libcxx/numerics/complex.number/__sqr.pass.cpp
index 4ef3d773b4e1f9e1273a339244a4a553ec17c31c..3a6aec0ac6791d93192da9aa3a52f65918d57b8f 100644
--- a/libcxx/test/libcxx/numerics/complex.number/__sqr.pass.cpp
+++ b/libcxx/test/libcxx/numerics/complex.number/__sqr.pass.cpp
@@ -72,9 +72,11 @@ test()
     assert(inf2.real() < 0);
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/numerics/complex.number/ccmplx/ccomplex.pass.cpp b/libcxx/test/libcxx/numerics/complex.number/ccmplx/ccomplex.pass.cpp
index 4fe737ed91510a80018a2de7d21d0304643a81ea..ff03bd09f841ab4cc773b149cbd71ca9e6a0549e 100644
--- a/libcxx/test/libcxx/numerics/complex.number/ccmplx/ccomplex.pass.cpp
+++ b/libcxx/test/libcxx/numerics/complex.number/ccmplx/ccomplex.pass.cpp
@@ -14,8 +14,10 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
     std::complex<double> d;
     (void)d;
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/numerics/complex.number/version.pass.cpp b/libcxx/test/libcxx/numerics/complex.number/version.pass.cpp
index c7dfb72dc006acd63ea6b6033cafee2fdcf3099c..ec3996e54f3d26e7f06e78f614412401e3165fbb 100644
--- a/libcxx/test/libcxx/numerics/complex.number/version.pass.cpp
+++ b/libcxx/test/libcxx/numerics/complex.number/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/numerics/numarray/version.pass.cpp b/libcxx/test/libcxx/numerics/numarray/version.pass.cpp
index ffe443d092a3f21d3e347288ab4feea92080f505..b921ae247accd6c20951058336bb92e89d7f4df3 100644
--- a/libcxx/test/libcxx/numerics/numarray/version.pass.cpp
+++ b/libcxx/test/libcxx/numerics/numarray/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/numerics/numeric.ops/version.pass.cpp b/libcxx/test/libcxx/numerics/numeric.ops/version.pass.cpp
index 2ae08be3e871c6a40a1420edf7baf4fcb6760b6b..50a07a639368caefd39864fe63194c326f7e73dc 100644
--- a/libcxx/test/libcxx/numerics/numeric.ops/version.pass.cpp
+++ b/libcxx/test/libcxx/numerics/numeric.ops/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/numerics/rand/rand.synopsis/version.pass.cpp b/libcxx/test/libcxx/numerics/rand/rand.synopsis/version.pass.cpp
index faddb6592c2a191a4fc608f1387c78425f842ce2..b9f876d0f9c025806fd11a4de2fde9570b000b4b 100644
--- a/libcxx/test/libcxx/numerics/rand/rand.synopsis/version.pass.cpp
+++ b/libcxx/test/libcxx/numerics/rand/rand.synopsis/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/selftest/not_test.sh.cpp b/libcxx/test/libcxx/selftest/not_test.sh.cpp
index 4e01967523dfded3bff73d26164286b7417893e2..8dbf708f0cb1ac67ca9ed0c94088d33e29e7757b 100644
--- a/libcxx/test/libcxx/selftest/not_test.sh.cpp
+++ b/libcxx/test/libcxx/selftest/not_test.sh.cpp
@@ -10,7 +10,7 @@
 // RUN: %build
 // RUN: not %run
 
-int main()
+int main(int, char**)
 {
   return 1;
 }
diff --git a/libcxx/test/libcxx/selftest/test.arc.pass.mm b/libcxx/test/libcxx/selftest/test.arc.pass.mm
index df4e83264bcaf833f1272ab20ce2618330e77d4b..eecdbb616185defef6173817bdcc81f76be6f872 100644
--- a/libcxx/test/libcxx/selftest/test.arc.pass.mm
+++ b/libcxx/test/libcxx/selftest/test.arc.pass.mm
@@ -11,6 +11,4 @@
 #error "arc should be enabled"
 #endif
 
-int main()
-{
-}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/libcxx/selftest/test.pass.cpp b/libcxx/test/libcxx/selftest/test.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/libcxx/selftest/test.pass.cpp
+++ b/libcxx/test/libcxx/selftest/test.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/selftest/test.pass.mm b/libcxx/test/libcxx/selftest/test.pass.mm
index e5e5f5c4130b9d059d6908e0ec61ca4bf36fb5f2..ba4d36bbe21106fb20f62b62bc075f27074bf517 100644
--- a/libcxx/test/libcxx/selftest/test.pass.mm
+++ b/libcxx/test/libcxx/selftest/test.pass.mm
@@ -11,6 +11,4 @@
 #error "arc should *not* be enabled"
 #endif
 
-int main()
-{
-}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/libcxx/selftest/test.sh.cpp b/libcxx/test/libcxx/selftest/test.sh.cpp
index b7e5e9d80aec86b67d9275761d569492ee91ccf8..1fc175413ab7cb5955a6a76128a20076c057f224 100644
--- a/libcxx/test/libcxx/selftest/test.sh.cpp
+++ b/libcxx/test/libcxx/selftest/test.sh.cpp
@@ -10,6 +10,8 @@
 // RUN: %build
 // RUN: %run
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/selftest/test_macros.pass.cpp b/libcxx/test/libcxx/selftest/test_macros.pass.cpp
index 63659e59470c1691301de28227ad572d0e59bd2a..d7baeb2f99fa61a445949f0c46a4d34e75ffb242 100644
--- a/libcxx/test/libcxx/selftest/test_macros.pass.cpp
+++ b/libcxx/test/libcxx/selftest/test_macros.pass.cpp
@@ -58,8 +58,10 @@ void test_libcxx_macros()
 //  ===== C++17 features =====
 }
 
-int main()
+int main(int, char**)
 {
     test_noexcept();
     test_libcxx_macros();
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/strings/basic.string/string.modifiers/clear_and_shrink_db1.pass.cpp b/libcxx/test/libcxx/strings/basic.string/string.modifiers/clear_and_shrink_db1.pass.cpp
index 4275bad39370f0060c072d61a1b2fac20046b4ea..b0de5d8792e76a02372d1abc2b59bdf296415d42 100644
--- a/libcxx/test/libcxx/strings/basic.string/string.modifiers/clear_and_shrink_db1.pass.cpp
+++ b/libcxx/test/libcxx/strings/basic.string/string.modifiers/clear_and_shrink_db1.pass.cpp
@@ -17,7 +17,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::string l = "Long string so that allocation definitely, for sure, absolutely happens. Probably.";
     std::string s = "short";
@@ -40,8 +40,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/libcxx/strings/basic.string/string.modifiers/erase_iter_db1.pass.cpp b/libcxx/test/libcxx/strings/basic.string/string.modifiers/erase_iter_db1.pass.cpp
index e397e0c8584e8cc6aa0af6433a57c02c992f957c..a5258f95d4d2e20dd52c2b67a2764f81b3ed010b 100644
--- a/libcxx/test/libcxx/strings/basic.string/string.modifiers/erase_iter_db1.pass.cpp
+++ b/libcxx/test/libcxx/strings/basic.string/string.modifiers/erase_iter_db1.pass.cpp
@@ -22,7 +22,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::string l1("123");
@@ -43,8 +43,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/libcxx/strings/basic.string/string.modifiers/erase_iter_db2.pass.cpp b/libcxx/test/libcxx/strings/basic.string/string.modifiers/erase_iter_db2.pass.cpp
index db11f17a17d49c298552d3680eab61b6643d5c76..099ce74f7432508ad4da87619a21e517c9d521f5 100644
--- a/libcxx/test/libcxx/strings/basic.string/string.modifiers/erase_iter_db2.pass.cpp
+++ b/libcxx/test/libcxx/strings/basic.string/string.modifiers/erase_iter_db2.pass.cpp
@@ -22,7 +22,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::string l1("123");
@@ -45,8 +45,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/libcxx/strings/basic.string/string.modifiers/erase_iter_iter_db1.pass.cpp b/libcxx/test/libcxx/strings/basic.string/string.modifiers/erase_iter_iter_db1.pass.cpp
index 736677b5e9f496bb64f48e9979461511eb5d7874..1802f6287db293f045057744116be08a40bd9404 100644
--- a/libcxx/test/libcxx/strings/basic.string/string.modifiers/erase_iter_iter_db1.pass.cpp
+++ b/libcxx/test/libcxx/strings/basic.string/string.modifiers/erase_iter_iter_db1.pass.cpp
@@ -22,7 +22,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::string l1("123");
@@ -43,8 +43,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/libcxx/strings/basic.string/string.modifiers/erase_iter_iter_db2.pass.cpp b/libcxx/test/libcxx/strings/basic.string/string.modifiers/erase_iter_iter_db2.pass.cpp
index 6f10d3f7e97e5d1e68b17d121e42594098f7d33f..fe65851ef77560f009aeb928cfe8fd163a4b3314 100644
--- a/libcxx/test/libcxx/strings/basic.string/string.modifiers/erase_iter_iter_db2.pass.cpp
+++ b/libcxx/test/libcxx/strings/basic.string/string.modifiers/erase_iter_iter_db2.pass.cpp
@@ -22,7 +22,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::string l1("123");
@@ -43,8 +43,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/libcxx/strings/basic.string/string.modifiers/erase_iter_iter_db3.pass.cpp b/libcxx/test/libcxx/strings/basic.string/string.modifiers/erase_iter_iter_db3.pass.cpp
index f6f23f111c1254170dcc1de5d05e75cf8dcc4f78..fad146451262e7d31b59e9c5f2978b1453e68171 100644
--- a/libcxx/test/libcxx/strings/basic.string/string.modifiers/erase_iter_iter_db3.pass.cpp
+++ b/libcxx/test/libcxx/strings/basic.string/string.modifiers/erase_iter_iter_db3.pass.cpp
@@ -22,7 +22,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::string l1("123");
@@ -43,8 +43,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/libcxx/strings/basic.string/string.modifiers/erase_iter_iter_db4.pass.cpp b/libcxx/test/libcxx/strings/basic.string/string.modifiers/erase_iter_iter_db4.pass.cpp
index 0446df020c31dfdd28da533431b5cbae0d420920..3186ad4492b0249f347318e4c182d9cea197f17f 100644
--- a/libcxx/test/libcxx/strings/basic.string/string.modifiers/erase_iter_iter_db4.pass.cpp
+++ b/libcxx/test/libcxx/strings/basic.string/string.modifiers/erase_iter_iter_db4.pass.cpp
@@ -22,7 +22,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::string l1("123");
@@ -41,8 +41,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/libcxx/strings/basic.string/string.modifiers/erase_pop_back_db1.pass.cpp b/libcxx/test/libcxx/strings/basic.string/string.modifiers/erase_pop_back_db1.pass.cpp
index 4276dfcdb35b943b3c0b7b3023e63edf1c278ced..2516a69f51f21d043ebfa66a993bd5589a60d9d7 100644
--- a/libcxx/test/libcxx/strings/basic.string/string.modifiers/erase_pop_back_db1.pass.cpp
+++ b/libcxx/test/libcxx/strings/basic.string/string.modifiers/erase_pop_back_db1.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 #if _LIBCPP_DEBUG >= 1
     {
@@ -28,4 +28,6 @@ int main()
         assert(false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/strings/basic.string/string.modifiers/insert_iter_char_db1.pass.cpp b/libcxx/test/libcxx/strings/basic.string/string.modifiers/insert_iter_char_db1.pass.cpp
index 39b1fde167e760f919e63460818deb9b0e5f7b70..7925e1597b728ee53c6c1afa3b8d120bd20ec33a 100644
--- a/libcxx/test/libcxx/strings/basic.string/string.modifiers/insert_iter_char_db1.pass.cpp
+++ b/libcxx/test/libcxx/strings/basic.string/string.modifiers/insert_iter_char_db1.pass.cpp
@@ -19,7 +19,7 @@
 #include <cassert>
 
 
-int main()
+int main(int, char**)
 {
 #if _LIBCPP_DEBUG >= 1
     {
@@ -30,4 +30,6 @@ int main()
         assert(false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/strings/basic.string/string.modifiers/insert_iter_size_char_db1.pass.cpp b/libcxx/test/libcxx/strings/basic.string/string.modifiers/insert_iter_size_char_db1.pass.cpp
index fb3771d9193c623f6468cc5449103cacf42724dd..81f888f86950eb2dc8c8317ffa0007e9fdd6ad84 100644
--- a/libcxx/test/libcxx/strings/basic.string/string.modifiers/insert_iter_size_char_db1.pass.cpp
+++ b/libcxx/test/libcxx/strings/basic.string/string.modifiers/insert_iter_size_char_db1.pass.cpp
@@ -17,7 +17,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
 #if _LIBCPP_DEBUG >= 1
     {
@@ -27,4 +27,6 @@ int main()
         assert(false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/strings/basic.string/string.modifiers/resize_default_initialized.pass.cpp b/libcxx/test/libcxx/strings/basic.string/string.modifiers/resize_default_initialized.pass.cpp
index ca9fb051277b1d6a6edea1e09ffdac2ec35691f0..3fab03c01c7fed5a7569602ad7719c83620065ee 100644
--- a/libcxx/test/libcxx/strings/basic.string/string.modifiers/resize_default_initialized.pass.cpp
+++ b/libcxx/test/libcxx/strings/basic.string/string.modifiers/resize_default_initialized.pass.cpp
@@ -56,7 +56,9 @@ void test_basic() {
   }
 }
 
-int main() {
+int main(int, char**) {
   test_basic();
   test_buffer_usage();
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/strings/c.strings/version_cctype.pass.cpp b/libcxx/test/libcxx/strings/c.strings/version_cctype.pass.cpp
index 9a0b4a6f05de5907bef522eeade61304f6ae1570..47e8576798a2b938d3c188ad1035716e4e5a0564 100644
--- a/libcxx/test/libcxx/strings/c.strings/version_cctype.pass.cpp
+++ b/libcxx/test/libcxx/strings/c.strings/version_cctype.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/strings/c.strings/version_cstring.pass.cpp b/libcxx/test/libcxx/strings/c.strings/version_cstring.pass.cpp
index a986f294ea409aa40f0592ffa5be6c5a121158e3..21388b41050c22bb2e31737e2a24e1e23a9533e3 100644
--- a/libcxx/test/libcxx/strings/c.strings/version_cstring.pass.cpp
+++ b/libcxx/test/libcxx/strings/c.strings/version_cstring.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/strings/c.strings/version_cuchar.pass.cpp b/libcxx/test/libcxx/strings/c.strings/version_cuchar.pass.cpp
index 40fa8ef237eabf62b679cbb6ed4eaaadb306fe54..8c6a9de70739d0a75ad1d6f2d9a76f1315e7fcf9 100644
--- a/libcxx/test/libcxx/strings/c.strings/version_cuchar.pass.cpp
+++ b/libcxx/test/libcxx/strings/c.strings/version_cuchar.pass.cpp
@@ -16,6 +16,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/strings/c.strings/version_cwchar.pass.cpp b/libcxx/test/libcxx/strings/c.strings/version_cwchar.pass.cpp
index 424c85fc2ece88c56f865efb1482c5e6e6481ffc..f7539d4e83866f023365d45ec62a9aa5d0eb6b7d 100644
--- a/libcxx/test/libcxx/strings/c.strings/version_cwchar.pass.cpp
+++ b/libcxx/test/libcxx/strings/c.strings/version_cwchar.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/strings/c.strings/version_cwctype.pass.cpp b/libcxx/test/libcxx/strings/c.strings/version_cwctype.pass.cpp
index 62320f8f5ea54488f0284960c90df84939e7cf24..06aacb1fee87006390418d1a288b895896467082 100644
--- a/libcxx/test/libcxx/strings/c.strings/version_cwctype.pass.cpp
+++ b/libcxx/test/libcxx/strings/c.strings/version_cwctype.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/strings/iterators.exceptions.pass.cpp b/libcxx/test/libcxx/strings/iterators.exceptions.pass.cpp
index 07787edff618c80ef8c9933d757de7ad195cd805..471e6bea560dddace8934961d9563ff1e190c3fd 100644
--- a/libcxx/test/libcxx/strings/iterators.exceptions.pass.cpp
+++ b/libcxx/test/libcxx/strings/iterators.exceptions.pass.cpp
@@ -33,7 +33,7 @@ static const bool expected = false;
 static const bool expected = true;
 #endif
 
-int main()
+int main(int, char**)
 {
 //  basic tests
     static_assert(( std::__libcpp_string_gets_noexcept_iterator<char *>::value), "");
@@ -84,4 +84,6 @@ int main()
     static_assert(( std::__libcpp_string_gets_noexcept_iterator<std::initializer_list<char>::iterator>              ::value), "");
     static_assert(( std::__libcpp_string_gets_noexcept_iterator<std::initializer_list<char>::const_iterator>        ::value), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/strings/iterators.noexcept.pass.cpp b/libcxx/test/libcxx/strings/iterators.noexcept.pass.cpp
index 01c15e3c9c95f6a31d47d197fc79916709bd4e9f..b46bc639b7a81d1f54ef8fac3621421a68013ed5 100644
--- a/libcxx/test/libcxx/strings/iterators.noexcept.pass.cpp
+++ b/libcxx/test/libcxx/strings/iterators.noexcept.pass.cpp
@@ -30,7 +30,7 @@
 #include "test_macros.h"
 #include "test_iterators.h"
 
-int main()
+int main(int, char**)
 {
 //  basic tests
     static_assert(( std::__libcpp_string_gets_noexcept_iterator<char *>::value), "");
@@ -77,4 +77,6 @@ int main()
     static_assert(( std::__libcpp_string_gets_noexcept_iterator<std::initializer_list<char>::iterator>              ::value), "");
     static_assert(( std::__libcpp_string_gets_noexcept_iterator<std::initializer_list<char>::const_iterator>        ::value), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/strings/version.pass.cpp b/libcxx/test/libcxx/strings/version.pass.cpp
index e378fce09cb0e7dc9b11fd86e124b4c5f4a6dd36..f106780e350a770dd550d0d485979f5441be5bcf 100644
--- a/libcxx/test/libcxx/strings/version.pass.cpp
+++ b/libcxx/test/libcxx/strings/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/thread/futures/futures.promise/set_exception.pass.cpp b/libcxx/test/libcxx/thread/futures/futures.promise/set_exception.pass.cpp
index 6109081d1d75d423df2712e4ddf3cd13cd09be37..78a8aaaa520024f89c10b8158b283918babf9b32 100644
--- a/libcxx/test/libcxx/thread/futures/futures.promise/set_exception.pass.cpp
+++ b/libcxx/test/libcxx/thread/futures/futures.promise/set_exception.pass.cpp
@@ -31,7 +31,7 @@
 #include <cassert>
 
 
-int main()
+int main(int, char**)
 {
     typedef std::__libcpp_debug_exception ExType;
     {
@@ -52,4 +52,6 @@ int main()
         } catch (ExType const&) {
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/thread/futures/futures.promise/set_exception_at_thread_exit.pass.cpp b/libcxx/test/libcxx/thread/futures/futures.promise/set_exception_at_thread_exit.pass.cpp
index 35fde08bd845feb6ab0fd9813d4d0138e5fe4da3..baf5ba9bf34c465cf29925e05b2743f2e737fadf 100644
--- a/libcxx/test/libcxx/thread/futures/futures.promise/set_exception_at_thread_exit.pass.cpp
+++ b/libcxx/test/libcxx/thread/futures/futures.promise/set_exception_at_thread_exit.pass.cpp
@@ -31,7 +31,7 @@
 #include <cassert>
 
 
-int main()
+int main(int, char**)
 {
     typedef std::__libcpp_debug_exception ExType;
     {
@@ -52,4 +52,6 @@ int main()
         } catch (ExType const& value) {
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/thread/futures/futures.task/types.pass.cpp b/libcxx/test/libcxx/thread/futures/futures.task/types.pass.cpp
index 22aae509e98dd139c47e144237b9c4a6b452d815..75bf2950331fd24feed9e04b43305ccc27392d29 100644
--- a/libcxx/test/libcxx/thread/futures/futures.task/types.pass.cpp
+++ b/libcxx/test/libcxx/thread/futures/futures.task/types.pass.cpp
@@ -24,7 +24,9 @@
 
 struct A {};
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::packaged_task<A(int, char)>::result_type, A>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/thread/futures/version.pass.cpp b/libcxx/test/libcxx/thread/futures/version.pass.cpp
index ceb0a5561f1b5382e49845ddf24b4d2ae2076cdd..fd2c30433001c23130d7102cb4add3eed7f8db12 100644
--- a/libcxx/test/libcxx/thread/futures/version.pass.cpp
+++ b/libcxx/test/libcxx/thread/futures/version.pass.cpp
@@ -16,6 +16,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/thread/thread.condition/PR30202_notify_from_pthread_created_thread.pass.cpp b/libcxx/test/libcxx/thread/thread.condition/PR30202_notify_from_pthread_created_thread.pass.cpp
index 8118835545fb19722c43ff9e3def6689bee27d61..2ad5c625604c89cbb3f20b85e3bcb69f2353c4af 100644
--- a/libcxx/test/libcxx/thread/thread.condition/PR30202_notify_from_pthread_created_thread.pass.cpp
+++ b/libcxx/test/libcxx/thread/thread.condition/PR30202_notify_from_pthread_created_thread.pass.cpp
@@ -45,7 +45,7 @@ void* func(void*)
     return nullptr;
 }
 
-int main()
+int main(int, char**)
 {
     {
     std::unique_lock<std::mutex> lk(mut);
@@ -72,4 +72,6 @@ int main()
     assert(t1-t0 > ms(250));
     t.join();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/thread/thread.condition/thread.condition.condvar/native_handle.pass.cpp b/libcxx/test/libcxx/thread/thread.condition/thread.condition.condvar/native_handle.pass.cpp
index f9facefffba8910cd91a8c33ed99d468112b8151..4b983ff05b201d64ddc04f1427f5994c3404565c 100644
--- a/libcxx/test/libcxx/thread/thread.condition/thread.condition.condvar/native_handle.pass.cpp
+++ b/libcxx/test/libcxx/thread/thread.condition/thread.condition.condvar/native_handle.pass.cpp
@@ -20,11 +20,13 @@
 #include <condition_variable>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::condition_variable::native_handle_type,
                                 pthread_cond_t*>::value), "");
     std::condition_variable cv;
     std::condition_variable::native_handle_type h = cv.native_handle();
     assert(h != nullptr);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/thread/thread.condition/version.pass.cpp b/libcxx/test/libcxx/thread/thread.condition/version.pass.cpp
index b3cfd4a3d2b1f395ec951404c90e319219933c8b..2354b3b9fd8ed0ce5705c7070432166a8c4a41ac 100644
--- a/libcxx/test/libcxx/thread/thread.condition/version.pass.cpp
+++ b/libcxx/test/libcxx/thread/thread.condition/version.pass.cpp
@@ -16,6 +16,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.class/native_handle.pass.cpp b/libcxx/test/libcxx/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.class/native_handle.pass.cpp
index 28137444a0e578d72f69643499532f342e8b038b..b85efcb64ca5b321dc2d79694aef3cd6aed21348 100644
--- a/libcxx/test/libcxx/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.class/native_handle.pass.cpp
+++ b/libcxx/test/libcxx/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.class/native_handle.pass.cpp
@@ -20,9 +20,11 @@
 #include <mutex>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::mutex m;
     pthread_mutex_t* h = m.native_handle();
     assert(h);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.recursive/native_handle.pass.cpp b/libcxx/test/libcxx/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.recursive/native_handle.pass.cpp
index 2a0eab4f481b32477c0f8253dd89628645f64713..4a6c53995305f13ba725a2274ac16e63fbd823e3 100644
--- a/libcxx/test/libcxx/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.recursive/native_handle.pass.cpp
+++ b/libcxx/test/libcxx/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.recursive/native_handle.pass.cpp
@@ -20,9 +20,11 @@
 #include <mutex>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::recursive_mutex m;
     pthread_mutex_t* h = m.native_handle();
     assert(h);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/thread/thread.mutex/thread_safety_annotations_not_enabled.pass.cpp b/libcxx/test/libcxx/thread/thread.mutex/thread_safety_annotations_not_enabled.pass.cpp
index 37f912bd99963535e6cbdc4ae25612bb9091b5c2..65a1d6e1225f55d95d907166de7be9fc0bc4a322 100644
--- a/libcxx/test/libcxx/thread/thread.mutex/thread_safety_annotations_not_enabled.pass.cpp
+++ b/libcxx/test/libcxx/thread/thread.mutex/thread_safety_annotations_not_enabled.pass.cpp
@@ -16,10 +16,12 @@
 
 #include <mutex>
 
-int main() {
+int main(int, char**) {
   std::mutex m;
   m.lock();
   {
     std::unique_lock<std::mutex> g(m, std::adopt_lock);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/thread/thread.mutex/thread_safety_lock_guard.pass.cpp b/libcxx/test/libcxx/thread/thread.mutex/thread_safety_lock_guard.pass.cpp
index 58545f8cedb2202661017d700dadc72cc578e854..8f8b6ce1c33ac7abdfe7e9109614546b66fa78c9 100644
--- a/libcxx/test/libcxx/thread/thread.mutex/thread_safety_lock_guard.pass.cpp
+++ b/libcxx/test/libcxx/thread/thread.mutex/thread_safety_lock_guard.pass.cpp
@@ -32,8 +32,10 @@ static void scoped() {
 #endif
 }
 
-int main() {
+int main(int, char**) {
   scoped();
   std::lock_guard<std::mutex> lock(m);
   foo++;
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/thread/thread.mutex/thread_safety_lock_unlock.pass.cpp b/libcxx/test/libcxx/thread/thread.mutex/thread_safety_lock_unlock.pass.cpp
index 5211c5e63b1fd426ce549d0c5a6d6c56405b1ab0..e29801228627b45293bf734e7c501e517e93c03b 100644
--- a/libcxx/test/libcxx/thread/thread.mutex/thread_safety_lock_unlock.pass.cpp
+++ b/libcxx/test/libcxx/thread/thread.mutex/thread_safety_lock_unlock.pass.cpp
@@ -23,8 +23,10 @@
 std::mutex m;
 int foo __attribute__((guarded_by(m)));
 
-int main() {
+int main(int, char**) {
   m.lock();
   foo++;
   m.unlock();
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/thread/thread.mutex/thread_safety_missing_unlock.fail.cpp b/libcxx/test/libcxx/thread/thread.mutex/thread_safety_missing_unlock.fail.cpp
index 9479566a9088b177e71465868aa29c8a9720383f..7dd3f5da2990a824b3571c7f014119fdda762dd7 100644
--- a/libcxx/test/libcxx/thread/thread.mutex/thread_safety_missing_unlock.fail.cpp
+++ b/libcxx/test/libcxx/thread/thread.mutex/thread_safety_missing_unlock.fail.cpp
@@ -22,6 +22,8 @@
 
 std::mutex m;
 
-int main() {
+int main(int, char**) {
   m.lock();
+
+  return 0;
 } // expected-error {{mutex 'm' is still held at the end of function}}
diff --git a/libcxx/test/libcxx/thread/thread.mutex/thread_safety_requires_capability.pass.cpp b/libcxx/test/libcxx/thread/thread.mutex/thread_safety_requires_capability.pass.cpp
index 772db283abc87a15e4854fb7fa589f358df923eb..2e427f217c85aa1dbc6fb44170bb82d38e5db7b5 100644
--- a/libcxx/test/libcxx/thread/thread.mutex/thread_safety_requires_capability.pass.cpp
+++ b/libcxx/test/libcxx/thread/thread.mutex/thread_safety_requires_capability.pass.cpp
@@ -27,8 +27,10 @@ void increment() __attribute__((requires_capability(m))) {
   foo++;
 }
 
-int main() {
+int main(int, char**) {
   m.lock();
   increment();
   m.unlock();
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/thread/thread.mutex/version.pass.cpp b/libcxx/test/libcxx/thread/thread.mutex/version.pass.cpp
index c996c1c7a376f0948447fdf1189d3a31fada9f34..abe4fda96aa1459f1a36f91c60a3dc09b8f72137 100644
--- a/libcxx/test/libcxx/thread/thread.mutex/version.pass.cpp
+++ b/libcxx/test/libcxx/thread/thread.mutex/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/thread/thread.threads/thread.thread.class/thread.thread.member/native_handle.pass.cpp b/libcxx/test/libcxx/thread/thread.threads/thread.thread.class/thread.thread.member/native_handle.pass.cpp
index fa69bec030020723d8df2072becfaa40e6327ded..1bf7e521d5cbc855823ec7f670703cd138445faf 100644
--- a/libcxx/test/libcxx/thread/thread.threads/thread.thread.class/thread.thread.member/native_handle.pass.cpp
+++ b/libcxx/test/libcxx/thread/thread.threads/thread.thread.class/thread.thread.member/native_handle.pass.cpp
@@ -43,7 +43,7 @@ public:
 int G::n_alive = 0;
 bool G::op_run = false;
 
-int main()
+int main(int, char**)
 {
     {
         G g;
@@ -52,4 +52,6 @@ int main()
         assert(pid != 0);
         t0.join();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/thread/thread.threads/thread.thread.class/types.pass.cpp b/libcxx/test/libcxx/thread/thread.threads/thread.thread.class/types.pass.cpp
index 9d021fe16c14a084a922b607437113db732939a1..4f6bd12064b440f986c48d5eb6e1b5cc8caddc5b 100644
--- a/libcxx/test/libcxx/thread/thread.threads/thread.thread.class/types.pass.cpp
+++ b/libcxx/test/libcxx/thread/thread.threads/thread.thread.class/types.pass.cpp
@@ -21,7 +21,9 @@
 #include <thread>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::thread::native_handle_type, pthread_t>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/thread/thread.threads/thread.thread.this/sleep_for.pass.cpp b/libcxx/test/libcxx/thread/thread.threads/thread.thread.this/sleep_for.pass.cpp
index 248284ea5131c1df2c56d279ad542baf5409d569..f11f40611335b351a68d156c74b6d5b92d01a9b2 100644
--- a/libcxx/test/libcxx/thread/thread.threads/thread.thread.this/sleep_for.pass.cpp
+++ b/libcxx/test/libcxx/thread/thread.threads/thread.thread.this/sleep_for.pass.cpp
@@ -34,7 +34,7 @@
 
 void sig_action(int) {}
 
-int main()
+int main(int, char**)
 {
     int ec;
     struct sigaction action;
@@ -64,4 +64,6 @@ int main()
     std::chrono::nanoseconds err = 5 * ms / 100;
     // The time slept is within 5% of 500ms
     assert(std::abs(ns.count()) < err.count());
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/thread/thread.threads/version.pass.cpp b/libcxx/test/libcxx/thread/thread.threads/version.pass.cpp
index 07e6c933f07c38a92b57e1af36927be229992d7f..3d7866228db318d7c224480f05d86253a61a0ed3 100644
--- a/libcxx/test/libcxx/thread/thread.threads/version.pass.cpp
+++ b/libcxx/test/libcxx/thread/thread.threads/version.pass.cpp
@@ -16,6 +16,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/type_traits/convert_to_integral.pass.cpp b/libcxx/test/libcxx/type_traits/convert_to_integral.pass.cpp
index 155f985d1530b047c54dbb4001080d5f0df01677..08b6b5e8b2aa4ea36d1e56753e3960a424bb817b 100644
--- a/libcxx/test/libcxx/type_traits/convert_to_integral.pass.cpp
+++ b/libcxx/test/libcxx/type_traits/convert_to_integral.pass.cpp
@@ -79,7 +79,7 @@ enum enum2 : unsigned long {
   value = std::numeric_limits<unsigned long>::max()
 };
 
-int main()
+int main(int, char**)
 {
   check_integral_types<bool, int>();
   check_integral_types<char, int>();
@@ -105,4 +105,6 @@ int main()
   check_enum_types<enum1, decltype(((Enum1UT)1) + 1)>();
   typedef std::underlying_type<enum2>::type Enum2UT;
   check_enum_types<enum2, decltype(((Enum2UT)1) + 1)>();
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/type_traits/lazy_metafunctions.pass.cpp b/libcxx/test/libcxx/type_traits/lazy_metafunctions.pass.cpp
index 84e80afe44a1bfb10eabceaadf5d49323a79a590..2ea1d6891f7b07e2b83cbb212de0d621147eafeb 100644
--- a/libcxx/test/libcxx/type_traits/lazy_metafunctions.pass.cpp
+++ b/libcxx/test/libcxx/type_traits/lazy_metafunctions.pass.cpp
@@ -128,9 +128,11 @@ void LazyOrTest() {
 }
 
 
-int main() {
+int main(int, char**) {
     LazyEnableIfTest();
     LazyNotTest();
     LazyAndTest();
     LazyOrTest();
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/any/size_and_alignment.pass.cpp b/libcxx/test/libcxx/utilities/any/size_and_alignment.pass.cpp
index 99ff5327309aa6cd8ebf5b8cbc908c32cdaac77b..4e3646660c42beeda662184b00038ed886b8615e 100644
--- a/libcxx/test/libcxx/utilities/any/size_and_alignment.pass.cpp
+++ b/libcxx/test/libcxx/utilities/any/size_and_alignment.pass.cpp
@@ -14,9 +14,11 @@
 
 #include <any>
 
-int main()
+int main(int, char**)
 {
     using std::any;
     static_assert(sizeof(any) == sizeof(void*)*4, "");
     static_assert(alignof(any) == alignof(void*), "");
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/any/small_type.pass.cpp b/libcxx/test/libcxx/utilities/any/small_type.pass.cpp
index f4cd46fdb7cb138099c0ad37c5a14e3afbd89669..9df6efc1402de151f46d17cc94a96956103bcb60 100644
--- a/libcxx/test/libcxx/utilities/any/small_type.pass.cpp
+++ b/libcxx/test/libcxx/utilities/any/small_type.pass.cpp
@@ -54,7 +54,7 @@ struct alignas(DoubleBufferAlignment) OverSizeAndAlignedType {
     char buff[BufferSize + 1];
 };
 
-int main()
+int main(int, char**)
 {
     using std::any;
     using std::__any_imp::_IsSmallObject;
@@ -110,4 +110,6 @@ int main()
         static_assert(alignof(T) > BufferAlignment, "");
         static_assert(!_IsSmallObject<T>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/any/version.pass.cpp b/libcxx/test/libcxx/utilities/any/version.pass.cpp
index 75e4544efe0d2b7de6b74e6fd1af8d596273c76e..ee5bc9928e1f14bf51cb337ad303840a010b34e7 100644
--- a/libcxx/test/libcxx/utilities/any/version.pass.cpp
+++ b/libcxx/test/libcxx/utilities/any/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/function.objects/func.require/bullet_1_2_3.pass.cpp b/libcxx/test/libcxx/utilities/function.objects/func.require/bullet_1_2_3.pass.cpp
index b2946ab815b2fc0f710a3fe71635e20f46245e7b..28ee3a39afeec6cdaf7b6c2c7f8a936c4f6ae6fa 100644
--- a/libcxx/test/libcxx/utilities/function.objects/func.require/bullet_1_2_3.pass.cpp
+++ b/libcxx/test/libcxx/utilities/function.objects/func.require/bullet_1_2_3.pass.cpp
@@ -271,7 +271,7 @@ void test_derived_from_ref_wrap() {
 }
 #endif
 
-int main() {
+int main(int, char**) {
     typedef void*& R;
     typedef ArgType A;
     TestCase<R(),                                   0, Q_None>::run();
@@ -367,4 +367,6 @@ int main() {
 
     test_derived_from_ref_wrap();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/function.objects/func.require/bullet_4_5_6.pass.cpp b/libcxx/test/libcxx/utilities/function.objects/func.require/bullet_4_5_6.pass.cpp
index 15ab7adb499f40e7546af1098b798f11c4197b82..ff7549d29c9af356dc335cfbd71341fdb657d3bc 100644
--- a/libcxx/test/libcxx/utilities/function.objects/func.require/bullet_4_5_6.pass.cpp
+++ b/libcxx/test/libcxx/utilities/function.objects/func.require/bullet_4_5_6.pass.cpp
@@ -206,10 +206,12 @@ private:
 
 
 
-int main() {
+int main(int, char**) {
     TestCase<ArgType>::run();
     TestCase<ArgType const>::run();
     TestCase<ArgType volatile>::run();
     TestCase<ArgType const volatile>::run();
     TestCase<ArgType*>::run();
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/function.objects/func.require/bullet_7.pass.cpp b/libcxx/test/libcxx/utilities/function.objects/func.require/bullet_7.pass.cpp
index 469452706ff67dcefb35920654ded23714b4f01d..fb789fa0a86cc1b070d35eb08e546a6aba9144a4 100644
--- a/libcxx/test/libcxx/utilities/function.objects/func.require/bullet_7.pass.cpp
+++ b/libcxx/test/libcxx/utilities/function.objects/func.require/bullet_7.pass.cpp
@@ -247,7 +247,7 @@ void runTestCase() {
     runFunctorTestCase <Sig, Arity, LValueCaster, ArgCaster>();
 };
 
-int main() {
+int main(int, char**) {
     typedef void*& R;
     typedef ArgType A;
     typedef A const CA;
@@ -323,4 +323,6 @@ int main() {
     runFunctorTestCase11<R(A&&) const volatile &&, 1, MoveCVCaster,       MC>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/function.objects/func.require/invoke.pass.cpp b/libcxx/test/libcxx/utilities/function.objects/func.require/invoke.pass.cpp
index acc0c778f2e80dc44bba0ca3e68ba5cec75061b8..e534553a87f0415d349eddd0974ad9612931b4e4 100644
--- a/libcxx/test/libcxx/utilities/function.objects/func.require/invoke.pass.cpp
+++ b/libcxx/test/libcxx/utilities/function.objects/func.require/invoke.pass.cpp
@@ -31,7 +31,7 @@ struct Type
 #endif
 };
 
-int main()
+int main(int, char**)
 {
     static_assert(sizeof(std::__invoke(&Type::f1, std::declval<Type        >())) == 1, "");
     static_assert(sizeof(std::__invoke(&Type::f2, std::declval<Type const  >())) == 2, "");
@@ -41,4 +41,6 @@ int main()
     static_assert(sizeof(std::__invoke(&Type::g3, std::declval<Type      &&>())) == 3, "");
     static_assert(sizeof(std::__invoke(&Type::g4, std::declval<Type const&&>())) == 4, "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/function.objects/refwrap/binary.pass.cpp b/libcxx/test/libcxx/utilities/function.objects/refwrap/binary.pass.cpp
index de0b9508ab0db1cc29f02b5591d7ad96a8c17f60..1f5bbcdef3ba86bef3526568f4407270e65a9a8b 100644
--- a/libcxx/test/libcxx/utilities/function.objects/refwrap/binary.pass.cpp
+++ b/libcxx/test/libcxx/utilities/function.objects/refwrap/binary.pass.cpp
@@ -46,7 +46,7 @@ struct C
     typedef int result_type;
 };
 
-int main()
+int main(int, char**)
 {
     static_assert((!std::is_base_of<std::binary_function<int, char, int>,
                                     std::reference_wrapper<functor1> >::value), "");
@@ -76,4 +76,6 @@ int main()
                                    std::reference_wrapper<float(C::*)(int)> >::value), "");
     static_assert((std::is_base_of<std::binary_function<const volatile C*, int, float>,
                                    std::reference_wrapper<float(C::*)(int) const volatile> >::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/function.objects/refwrap/unary.pass.cpp b/libcxx/test/libcxx/utilities/function.objects/refwrap/unary.pass.cpp
index 27e2763db070617c1eb9faf066a086b5b87ecc2c..429722e4711ec292c348b1148fecff5515974fc4 100644
--- a/libcxx/test/libcxx/utilities/function.objects/refwrap/unary.pass.cpp
+++ b/libcxx/test/libcxx/utilities/function.objects/refwrap/unary.pass.cpp
@@ -46,7 +46,7 @@ struct C
     typedef int result_type;
 };
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::unary_function<int, char>,
                                    std::reference_wrapper<functor1> >::value), "");
@@ -74,4 +74,6 @@ int main()
                                    std::reference_wrapper<float(C::*)() const volatile> >::value), "");
     static_assert((!std::is_base_of<std::unary_function<C*, float>,
                                    std::reference_wrapper<float(C::*)(int)> >::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/function.objects/unord.hash/murmur2_or_cityhash_ubsan_unsigned_overflow_ignored.pass.cpp b/libcxx/test/libcxx/utilities/function.objects/unord.hash/murmur2_or_cityhash_ubsan_unsigned_overflow_ignored.pass.cpp
index 7241bc059ce2980f88d6a9039f3f5f3e838d9bf7..54f4db7644605e15e977a24c1833163df2f69b4c 100644
--- a/libcxx/test/libcxx/utilities/function.objects/unord.hash/murmur2_or_cityhash_ubsan_unsigned_overflow_ignored.pass.cpp
+++ b/libcxx/test/libcxx/utilities/function.objects/unord.hash/murmur2_or_cityhash_ubsan_unsigned_overflow_ignored.pass.cpp
@@ -28,7 +28,7 @@ void test(const void* key, int len) {
   }
 }
 
-int main() {
+int main(int, char**) {
   const std::string TestCases[] = {
       "abcdaoeuaoeclaoeoaeuaoeuaousaotehu]+}sthoasuthaoesutahoesutaohesutaoeusaoetuhasoetuhaoseutaoseuthaoesutaohes"
       "00000000000000000000000000000000000000000000000000000000000000000000000",
@@ -37,4 +37,6 @@ int main() {
   const size_t NumCases = sizeof(TestCases)/sizeof(TestCases[0]);
   for (size_t i=0; i < NumCases; ++i)
     test(TestCases[i].data(), TestCases[i].length());
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/function.objects/version.pass.cpp b/libcxx/test/libcxx/utilities/function.objects/version.pass.cpp
index 41bbca6f638a6fd142aee2abb725247017dd0d2e..6f8540f1a2425db54404ea21ea1128f16c5c1113 100644
--- a/libcxx/test/libcxx/utilities/function.objects/version.pass.cpp
+++ b/libcxx/test/libcxx/utilities/function.objects/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/memory/util.dynamic.safety/get_pointer_safety_cxx03.pass.cpp b/libcxx/test/libcxx/utilities/memory/util.dynamic.safety/get_pointer_safety_cxx03.pass.cpp
index d0410c51bdcafc0e69f1d2ec6dd176b4fd7474e3..deab4368af29f6417becfd9db4f237329c84e592 100644
--- a/libcxx/test/libcxx/utilities/memory/util.dynamic.safety/get_pointer_safety_cxx03.pass.cpp
+++ b/libcxx/test/libcxx/utilities/memory/util.dynamic.safety/get_pointer_safety_cxx03.pass.cpp
@@ -28,7 +28,7 @@ void test_pr26961() {
 }
 #endif
 
-int main()
+int main(int, char**)
 {
 #ifndef TEST_IS_UNSUPPORTED
   {
@@ -42,4 +42,6 @@ int main()
     test_pr26961();
   }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/memory/util.dynamic.safety/get_pointer_safety_new_abi.pass.cpp b/libcxx/test/libcxx/utilities/memory/util.dynamic.safety/get_pointer_safety_new_abi.pass.cpp
index 2ff19d45e425984ba0a66001ad08906b21f9a44c..c8e0c7292998ea06e01b31eeb2fc9c3f4323981d 100644
--- a/libcxx/test/libcxx/utilities/memory/util.dynamic.safety/get_pointer_safety_new_abi.pass.cpp
+++ b/libcxx/test/libcxx/utilities/memory/util.dynamic.safety/get_pointer_safety_new_abi.pass.cpp
@@ -18,7 +18,7 @@
 #include <memory>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
   {
     static_assert(std::is_enum<std::pointer_safety>::value, "");
@@ -34,4 +34,6 @@ int main()
            r == std::pointer_safety::preferred ||
            r == std::pointer_safety::strict);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/memory/util.smartptr/race_condition.pass.cpp b/libcxx/test/libcxx/utilities/memory/util.smartptr/race_condition.pass.cpp
index e3091aa5a23141f3f80b59162b2fc32e343a9e19..bf12e145942b6372364911ce313c9f6f4db86ae2 100644
--- a/libcxx/test/libcxx/utilities/memory/util.smartptr/race_condition.pass.cpp
+++ b/libcxx/test/libcxx/utilities/memory/util.smartptr/race_condition.pass.cpp
@@ -77,7 +77,7 @@ void run_test(Ptr p) {
     assert(p.use_count() == 3);
 }
 
-int main() {
+int main(int, char**) {
   {
     // Test with out-of-place shared_count.
     Ptr p(new int(42));
@@ -91,4 +91,6 @@ int main() {
     run_test(p);
     assert(p.use_count() == 1);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/memory/util.smartptr/util.smartptr.shared/function_type_default_deleter.fail.cpp b/libcxx/test/libcxx/utilities/memory/util.smartptr/util.smartptr.shared/function_type_default_deleter.fail.cpp
index c94ce75fe6857c0c3f3864f64a547ddc837837f7..e9b4257a7240a1f51c3c6bcfef12b5fb863fdb9e 100644
--- a/libcxx/test/libcxx/utilities/memory/util.smartptr/util.smartptr.shared/function_type_default_deleter.fail.cpp
+++ b/libcxx/test/libcxx/utilities/memory/util.smartptr/util.smartptr.shared/function_type_default_deleter.fail.cpp
@@ -29,7 +29,7 @@ struct Deleter {
   }
 };
 
-int main() {
+int main(int, char**) {
   {
     SPtr<0> s; // OK
     SPtr<1> s1(nullptr); // OK
@@ -41,4 +41,6 @@ int main() {
     SPtr<4> s4(getFn<4>()); // expected-note {{requested here}}
     SPtr<5> s5(getFn<5>(), std::default_delete<FnType<5>>{}); // expected-note {{requested here}}
   }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/memory/version.pass.cpp b/libcxx/test/libcxx/utilities/memory/version.pass.cpp
index e5359a5d4c794b93afe6b9712ddfc5d66d48b222..5b10e1425f5ec6400cbc21efbebc6c3b49aa3bd9 100644
--- a/libcxx/test/libcxx/utilities/memory/version.pass.cpp
+++ b/libcxx/test/libcxx/utilities/memory/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/meta/is_referenceable.pass.cpp b/libcxx/test/libcxx/utilities/meta/is_referenceable.pass.cpp
index 376f295d1f31dcd45faa41263f57abb6a13074d0..bdd0a4574b0954ba7c25051dfbaab3daee326200 100644
--- a/libcxx/test/libcxx/utilities/meta/is_referenceable.pass.cpp
+++ b/libcxx/test/libcxx/utilities/meta/is_referenceable.pass.cpp
@@ -189,4 +189,6 @@ static_assert(( std::__is_referenceable<void (Foo::*)(int, float, Foo &, ...) &&
 static_assert(( std::__is_referenceable<void (Foo::*)(int, float, Foo &, ...) const &&>::value), "");
 #endif
 
-int main () {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/libcxx/utilities/meta/meta.unary/meta.unary.prop/__has_operator_addressof.pass.cpp b/libcxx/test/libcxx/utilities/meta/meta.unary/meta.unary.prop/__has_operator_addressof.pass.cpp
index 010f8f48dd1d55c61ea25d02640bb99a75a79b07..80bd2e73861aebcab3b8af8ff2c60a54267eb439 100644
--- a/libcxx/test/libcxx/utilities/meta/meta.unary/meta.unary.prop/__has_operator_addressof.pass.cpp
+++ b/libcxx/test/libcxx/utilities/meta/meta.unary/meta.unary.prop/__has_operator_addressof.pass.cpp
@@ -55,7 +55,7 @@ struct J
 };
 
 
-int main()
+int main(int, char**)
 {
     static_assert(std::__has_operator_addressof<int>::value == false, "");
     static_assert(std::__has_operator_addressof<A>::value == false, "");
@@ -65,4 +65,6 @@ int main()
     static_assert(std::__has_operator_addressof<G>::value == true, "");
     static_assert(std::__has_operator_addressof<H>::value == true, "");
     static_assert(std::__has_operator_addressof<J>::value == true, "");
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/meta/meta.unary/meta.unary.prop/missing_is_aggregate_trait.fail.cpp b/libcxx/test/libcxx/utilities/meta/meta.unary/meta.unary.prop/missing_is_aggregate_trait.fail.cpp
index 0be653d7fd9b1bd245caada4b90d390738c46947..8606769ee1b6c209a7ff89bba3c990cb0d116aa9 100644
--- a/libcxx/test/libcxx/utilities/meta/meta.unary/meta.unary.prop/missing_is_aggregate_trait.fail.cpp
+++ b/libcxx/test/libcxx/utilities/meta/meta.unary/meta.unary.prop/missing_is_aggregate_trait.fail.cpp
@@ -15,7 +15,7 @@
 
 #include <type_traits>
 
-int main ()
+int main(int, char**)
 {
 #ifdef _LIBCPP_HAS_NO_IS_AGGREGATE
   // This should not compile when _LIBCPP_HAS_NO_IS_AGGREGATE is defined.
@@ -24,4 +24,6 @@ int main ()
 #else
 #error Forcing failure...
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/meta/version.pass.cpp b/libcxx/test/libcxx/utilities/meta/version.pass.cpp
index 831ca6672febcb457c709049c1ebda70b2bfc7e6..7f4cbd841dd8184ac3a064ebe0881aa1644b3ef1 100644
--- a/libcxx/test/libcxx/utilities/meta/version.pass.cpp
+++ b/libcxx/test/libcxx/utilities/meta/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/optional/optional.object/optional.object.assign/copy.pass.cpp b/libcxx/test/libcxx/utilities/optional/optional.object/optional.object.assign/copy.pass.cpp
index 47fb9d5ad1737fdb99e9bf2252f7f405ac07f4bf..1f559904c88d49226ea3372f13d508275bca3a53 100644
--- a/libcxx/test/libcxx/utilities/optional/optional.object/optional.object.assign/copy.pass.cpp
+++ b/libcxx/test/libcxx/utilities/optional/optional.object/optional.object.assign/copy.pass.cpp
@@ -53,7 +53,7 @@ test()
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     {
         using T = int;
@@ -70,4 +70,6 @@ int main()
 
     static_assert(!(std::is_copy_assignable<optional<Z1>>::value), "");
     static_assert(!(std::is_copy_assignable<optional<Z2>>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/optional/optional.object/optional.object.assign/move.pass.cpp b/libcxx/test/libcxx/utilities/optional/optional.object/optional.object.assign/move.pass.cpp
index 5063d69c3f1e67f2349bbc9e4744bafada9409c9..325bcb452a0fa15af98cb54f198706691354d967 100644
--- a/libcxx/test/libcxx/utilities/optional/optional.object/optional.object.assign/move.pass.cpp
+++ b/libcxx/test/libcxx/utilities/optional/optional.object/optional.object.assign/move.pass.cpp
@@ -50,7 +50,7 @@ test()
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     {
         using T = int;
@@ -67,4 +67,6 @@ int main()
 
     static_assert(!(std::is_move_assignable<optional<Z1>>::value), "");
     static_assert(!(std::is_move_assignable<optional<Z2>>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/optional/optional.object/optional.object.ctor/copy.pass.cpp b/libcxx/test/libcxx/utilities/optional/optional.object/optional.object.ctor/copy.pass.cpp
index 50e27e99e6f924b2d6757f82594baa48eaedcf1d..694ab01569cb25b60884e1976d97f248b2c208f7 100644
--- a/libcxx/test/libcxx/utilities/optional/optional.object/optional.object.ctor/copy.pass.cpp
+++ b/libcxx/test/libcxx/utilities/optional/optional.object/optional.object.ctor/copy.pass.cpp
@@ -35,7 +35,7 @@ struct Z
     Z& operator=(const Z&) = delete;
 };
 
-int main()
+int main(int, char**)
 {
     {
         using T = int;
@@ -55,4 +55,6 @@ int main()
     static_assert(!(std::is_trivially_copy_constructible<optional<std::string>>::value), "");
 
     static_assert(!(std::is_copy_constructible<optional<Z>>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/optional/optional.object/optional.object.ctor/move.pass.cpp b/libcxx/test/libcxx/utilities/optional/optional.object/optional.object.ctor/move.pass.cpp
index ff66a1ea9bb6ebc97c2b308b6df3f762da152a20..383eaa98649be49b44ca0657741e4e31ce7f1c14 100644
--- a/libcxx/test/libcxx/utilities/optional/optional.object/optional.object.ctor/move.pass.cpp
+++ b/libcxx/test/libcxx/utilities/optional/optional.object/optional.object.ctor/move.pass.cpp
@@ -36,7 +36,7 @@ struct Z
     Z& operator=(const Z&) = delete;
 };
 
-int main()
+int main(int, char**)
 {
     {
         using T = int;
@@ -56,4 +56,6 @@ int main()
     static_assert(!(std::is_trivially_move_constructible<optional<std::string>>::value), "");
 
     static_assert(!(std::is_move_constructible<optional<Z>>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/optional/optional.object/triviality.abi.pass.cpp b/libcxx/test/libcxx/utilities/optional/optional.object/triviality.abi.pass.cpp
index d09af830fa0721139964b20ba462b680dfe28128..36f5bb937392164850927f2eca255c80ec09d169 100644
--- a/libcxx/test/libcxx/utilities/optional/optional.object/triviality.abi.pass.cpp
+++ b/libcxx/test/libcxx/utilities/optional/optional.object/triviality.abi.pass.cpp
@@ -85,7 +85,7 @@ struct TrivialCopyNonTrivialMove {
     TrivialCopyNonTrivialMove& operator=(TrivialCopyNonTrivialMove&&) { return *this; }
 };
 
-int main()
+int main(int, char**)
 {
     sink(
         ImplicitTypes::ApplyTypes<DoTestsMetafunction>{},
@@ -94,4 +94,6 @@ int main()
         NonTrivialTypes::ApplyTypes<DoTestsMetafunction>{},
         DoTestsMetafunction<TrivialMoveNonTrivialCopy, TrivialCopyNonTrivialMove>{}
     );
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/optional/version.pass.cpp b/libcxx/test/libcxx/utilities/optional/version.pass.cpp
index 7dc36057c7c5292b64b903348f7f7bb2cb45837e..49b263a37e58758313c5f57ab9e498402686551d 100644
--- a/libcxx/test/libcxx/utilities/optional/version.pass.cpp
+++ b/libcxx/test/libcxx/utilities/optional/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/ratio/version.pass.cpp b/libcxx/test/libcxx/utilities/ratio/version.pass.cpp
index a38c07515078fa152516df3fc0075156a526d067..112111c37bfd5d990155081035f8ac911802813f 100644
--- a/libcxx/test/libcxx/utilities/ratio/version.pass.cpp
+++ b/libcxx/test/libcxx/utilities/ratio/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/template.bitset/includes.pass.cpp b/libcxx/test/libcxx/utilities/template.bitset/includes.pass.cpp
index 78c39989f3af1099f7677f4c6c07647a94fe3488..3ec17b079ebc8389a4bd4c6370ef8dbe7ff6a7fb 100644
--- a/libcxx/test/libcxx/utilities/template.bitset/includes.pass.cpp
+++ b/libcxx/test/libcxx/utilities/template.bitset/includes.pass.cpp
@@ -26,6 +26,8 @@
 #error <iosfwd> has not been included
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/template.bitset/version.pass.cpp b/libcxx/test/libcxx/utilities/template.bitset/version.pass.cpp
index 9cb31d5fe8adc84666db78220ea27caf9d7d56f4..94df4d1bab99e7af26e5ee9036dc65b05fc41b2a 100644
--- a/libcxx/test/libcxx/utilities/template.bitset/version.pass.cpp
+++ b/libcxx/test/libcxx/utilities/template.bitset/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/time/date.time/asctime.thread-unsafe.fail.cpp b/libcxx/test/libcxx/utilities/time/date.time/asctime.thread-unsafe.fail.cpp
index 8ea12b712b4f5bcf304134e4f6ae1c676e5068ff..ed49ac28693e9d2e1992604361285a7f3fef642d 100644
--- a/libcxx/test/libcxx/utilities/time/date.time/asctime.thread-unsafe.fail.cpp
+++ b/libcxx/test/libcxx/utilities/time/date.time/asctime.thread-unsafe.fail.cpp
@@ -10,8 +10,10 @@
 
 #include <ctime>
 
-int main() {
+int main(int, char**) {
     // asctime is not thread-safe.
     std::time_t t = 0;
     std::asctime(&t);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/time/date.time/ctime.thread-unsafe.fail.cpp b/libcxx/test/libcxx/utilities/time/date.time/ctime.thread-unsafe.fail.cpp
index 3e1986bf46cad8eb90d2833cf7017d55c5573e0c..741de667e9e7007d474e0af7e190ccb4ccaf53df 100644
--- a/libcxx/test/libcxx/utilities/time/date.time/ctime.thread-unsafe.fail.cpp
+++ b/libcxx/test/libcxx/utilities/time/date.time/ctime.thread-unsafe.fail.cpp
@@ -10,8 +10,10 @@
 
 #include <ctime>
 
-int main() {
+int main(int, char**) {
     // ctime is not thread-safe.
     std::time_t t = 0;
     std::ctime(&t);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/time/date.time/gmtime.thread-unsafe.fail.cpp b/libcxx/test/libcxx/utilities/time/date.time/gmtime.thread-unsafe.fail.cpp
index 979c92fbd1fde561a01cb75eefebab2b46acccdc..ce7f782036b6ef25908982a66a4a8f9ac1061b6f 100644
--- a/libcxx/test/libcxx/utilities/time/date.time/gmtime.thread-unsafe.fail.cpp
+++ b/libcxx/test/libcxx/utilities/time/date.time/gmtime.thread-unsafe.fail.cpp
@@ -10,8 +10,10 @@
 
 #include <ctime>
 
-int main() {
+int main(int, char**) {
     // gmtime is not thread-safe.
     std::time_t t = 0;
     std::gmtime(&t);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/time/date.time/localtime.thread-unsafe.fail.cpp b/libcxx/test/libcxx/utilities/time/date.time/localtime.thread-unsafe.fail.cpp
index a68a5c33f044ed0229f14585e843e9a51ad3ecb6..8f803d91c0c840bf62f5db8b12500416275c0e99 100644
--- a/libcxx/test/libcxx/utilities/time/date.time/localtime.thread-unsafe.fail.cpp
+++ b/libcxx/test/libcxx/utilities/time/date.time/localtime.thread-unsafe.fail.cpp
@@ -10,8 +10,10 @@
 
 #include <ctime>
 
-int main() {
+int main(int, char**) {
     // localtime is not thread-safe.
     std::time_t t = 0;
     std::localtime(&t);
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/time/version.pass.cpp b/libcxx/test/libcxx/utilities/time/version.pass.cpp
index 2e3373711202f87b388dfc0941b0e6fe7c1b2956..d1093dd4afcf6977da668a6cde2b41c8abade69c 100644
--- a/libcxx/test/libcxx/utilities/time/version.pass.cpp
+++ b/libcxx/test/libcxx/utilities/time/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/tuple/tuple.tuple/empty_member.pass.cpp b/libcxx/test/libcxx/utilities/tuple/tuple.tuple/empty_member.pass.cpp
index 76cb442b268f16a97cb6ba7bf69071074d28fecd..20938208794e5013d06457411c3d15763e6c2ad7 100644
--- a/libcxx/test/libcxx/utilities/tuple/tuple.tuple/empty_member.pass.cpp
+++ b/libcxx/test/libcxx/utilities/tuple/tuple.tuple/empty_member.pass.cpp
@@ -20,7 +20,7 @@ struct A {};
 
 struct B {};
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::tuple<int, A> T;
@@ -42,4 +42,6 @@ int main()
         typedef std::tuple<int, A, B> T;
         static_assert((sizeof(T) == sizeof(int)), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/tuple/tuple.tuple/tuple.cnstr/PR20855_tuple_ref_binding_diagnostics.fail.cpp b/libcxx/test/libcxx/utilities/tuple/tuple.tuple/tuple.cnstr/PR20855_tuple_ref_binding_diagnostics.fail.cpp
index d1a371b5defc61d8c710ad0728739d72cea0cb2f..a4c43ba5d2aa55d47ec343342b09455f9d0a63ad 100644
--- a/libcxx/test/libcxx/utilities/tuple/tuple.tuple/tuple.cnstr/PR20855_tuple_ref_binding_diagnostics.fail.cpp
+++ b/libcxx/test/libcxx/utilities/tuple/tuple.tuple/tuple.cnstr/PR20855_tuple_ref_binding_diagnostics.fail.cpp
@@ -43,7 +43,7 @@ template <class ...Args>
 void F(typename CannotDeduce<std::tuple<Args...>>::type const&) {}
 
 
-int main() {
+int main(int, char**) {
 #if TEST_HAS_BUILTIN_IDENTIFIER(__reference_binds_to_temporary)
   // Test that we emit our diagnostic from the library.
   // expected-error@tuple:* 8 {{"Attempted construction of reference element binds to a temporary whose lifetime has ended"}}
@@ -81,4 +81,6 @@ int main() {
 #error force failure
 // expected-error@-1 {{force failure}}
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/tuple/tuple.tuple/tuple.cnstr/disable_reduced_arity_initialization_extension.pass.cpp b/libcxx/test/libcxx/utilities/tuple/tuple.tuple/tuple.cnstr/disable_reduced_arity_initialization_extension.pass.cpp
index 2eb85c6660876bfad6106452d965392591ffbfb6..8e4cb52bf18f7a8ef5ace468243d5990be935919 100644
--- a/libcxx/test/libcxx/utilities/tuple/tuple.tuple/tuple.cnstr/disable_reduced_arity_initialization_extension.pass.cpp
+++ b/libcxx/test/libcxx/utilities/tuple/tuple.tuple/tuple.cnstr/disable_reduced_arity_initialization_extension.pass.cpp
@@ -77,7 +77,7 @@ void test_example_from_docs() {
   assert(std::get<2>(tup) == std::error_code{});
 }
 
-int main()
+int main(int, char**)
 {
     {
         using E = MoveOnly;
@@ -104,4 +104,6 @@ int main()
     // constructor extensions.
     test_default_constructible_extension_sfinae();
     test_example_from_docs();
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/tuple/tuple.tuple/tuple.cnstr/enable_reduced_arity_initialization_extension.pass.cpp b/libcxx/test/libcxx/utilities/tuple/tuple.tuple/tuple.cnstr/enable_reduced_arity_initialization_extension.pass.cpp
index 12d2268550e253fcb14df703d05fe32b436be9f1..f012d4c5fa497eb98a321cdd57fea399dfcdbe22 100644
--- a/libcxx/test/libcxx/utilities/tuple/tuple.tuple/tuple.cnstr/enable_reduced_arity_initialization_extension.pass.cpp
+++ b/libcxx/test/libcxx/utilities/tuple/tuple.tuple/tuple.cnstr/enable_reduced_arity_initialization_extension.pass.cpp
@@ -89,7 +89,7 @@ void test_example_from_docs() {
   assert(std::get<2>(tup) == std::error_code{});
 }
 
-int main()
+int main(int, char**)
 {
 
     {
@@ -113,4 +113,6 @@ int main()
     // constructor extensions.
     test_default_constructible_extension_sfinae();
     test_example_from_docs();
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/tuple/version.pass.cpp b/libcxx/test/libcxx/utilities/tuple/version.pass.cpp
index 8149eb07e058307135c536ddd2f1fbe295c1b569..28232a99b13f70080ab30fab234e6aca59b242b2 100644
--- a/libcxx/test/libcxx/utilities/tuple/version.pass.cpp
+++ b/libcxx/test/libcxx/utilities/tuple/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/type.index/version.pass.cpp b/libcxx/test/libcxx/utilities/type.index/version.pass.cpp
index 94a1ebf43cf577ccdb18cb06de079cccd3632120..38cd0254a580362493624f0042b3e34fa440e349 100644
--- a/libcxx/test/libcxx/utilities/type.index/version.pass.cpp
+++ b/libcxx/test/libcxx/utilities/type.index/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/utility/__is_inplace_index.pass.cpp b/libcxx/test/libcxx/utilities/utility/__is_inplace_index.pass.cpp
index 85308201274426d36865bb2781523013024cea52..a2559f208f37c22864ad56d25a87880f8df8eb4b 100644
--- a/libcxx/test/libcxx/utilities/utility/__is_inplace_index.pass.cpp
+++ b/libcxx/test/libcxx/utilities/utility/__is_inplace_index.pass.cpp
@@ -14,7 +14,7 @@
 
 struct S {};
 
-int main() {
+int main(int, char**) {
   using I = std::in_place_index_t<0>;
   static_assert( std::__is_inplace_index<I>::value, "");
   static_assert( std::__is_inplace_index<const I>::value, "");
@@ -30,4 +30,6 @@ int main() {
   static_assert(!std::__is_inplace_index<void>::value, "");
   static_assert(!std::__is_inplace_index<int>::value, "");
   static_assert(!std::__is_inplace_index<S>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/utility/__is_inplace_type.pass.cpp b/libcxx/test/libcxx/utilities/utility/__is_inplace_type.pass.cpp
index 9a6739c275360c35989472714ffbe54165419a81..534fb505926607b96ec7c7c6cfcb20686003b44c 100644
--- a/libcxx/test/libcxx/utilities/utility/__is_inplace_type.pass.cpp
+++ b/libcxx/test/libcxx/utilities/utility/__is_inplace_type.pass.cpp
@@ -14,7 +14,7 @@
 
 struct S {};
 
-int main() {
+int main(int, char**) {
   using T = std::in_place_type_t<int>;
   static_assert( std::__is_inplace_type<T>::value, "");
   static_assert( std::__is_inplace_type<const T>::value, "");
@@ -30,4 +30,6 @@ int main() {
   static_assert(!std::__is_inplace_type<void>::value, "");
   static_assert(!std::__is_inplace_type<int>::value, "");
   static_assert(!std::__is_inplace_type<S>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/U_V.pass.cpp b/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/U_V.pass.cpp
index 6e65d9b5289ec499b1123e0426f0d316544ac640..e03fa6d7f3d39952db3503af314eb748f471017f 100644
--- a/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/U_V.pass.cpp
+++ b/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/U_V.pass.cpp
@@ -37,7 +37,7 @@ struct ImplicitNothrowT {
     int value;
 };
 
-int main() {
+int main(int, char**) {
     { // explicit noexcept test
         static_assert(!std::is_nothrow_constructible<std::pair<ExplicitT, ExplicitT>, int, int>::value, "");
         static_assert(!std::is_nothrow_constructible<std::pair<ExplicitNothrowT, ExplicitT>, int, int>::value, "");
@@ -50,4 +50,6 @@ int main() {
         static_assert(!std::is_nothrow_constructible<std::pair<ImplicitT, ImplicitNothrowT>, int, int>::value, "");
         static_assert( std::is_nothrow_constructible<std::pair<ImplicitNothrowT, ImplicitNothrowT>, int, int>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/assign_tuple_like.pass.cpp b/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/assign_tuple_like.pass.cpp
index 17a2b5a41ec025b96f39e6d39f959c27f6ee8bb0..5765700fe136002bfb92d51434cd66a24b5b693a 100644
--- a/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/assign_tuple_like.pass.cpp
+++ b/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/assign_tuple_like.pass.cpp
@@ -27,7 +27,7 @@
 #pragma clang diagnostic ignored "-Wmissing-braces"
 #endif
 
-int main()
+int main(int, char**)
 {
     using C = TestTypes::TestType;
     {
@@ -100,4 +100,6 @@ int main()
        assert(p.first.value == 42);
        assert(p.second.value == -42);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/const_first_const_second.pass.cpp b/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/const_first_const_second.pass.cpp
index 923bd0dd64ab597d42480015ad1627c0c4f217ca..a2fac173ec7cc8263fab68a8824bd3f9e6bbec0e 100644
--- a/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/const_first_const_second.pass.cpp
+++ b/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/const_first_const_second.pass.cpp
@@ -37,7 +37,7 @@ struct ImplicitNothrowT {
     ImplicitNothrowT(ImplicitNothrowT const&) noexcept {}
 };
 
-int main() {
+int main(int, char**) {
     { // explicit noexcept test
         static_assert(!std::is_nothrow_constructible<std::pair<ExplicitT, ExplicitT>,
                                                      ExplicitT const&, ExplicitT const&>::value, "");
@@ -58,4 +58,6 @@ int main() {
         static_assert( std::is_nothrow_constructible<std::pair<ImplicitNothrowT, ImplicitNothrowT>,
                                                      ImplicitNothrowT const&, ImplicitNothrowT const&>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/const_pair_U_V.pass.cpp b/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/const_pair_U_V.pass.cpp
index 68d294bd68c4e0002280d395bfa9406e753581bc..16d714ab9a7edc5778a59db9f16b08145580625a 100644
--- a/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/const_pair_U_V.pass.cpp
+++ b/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/const_pair_U_V.pass.cpp
@@ -39,7 +39,7 @@ struct ImplicitNothrowT {
     int value;
 };
 
-int main() {
+int main(int, char**) {
     { // explicit noexcept test
         static_assert(!std::is_nothrow_constructible<std::pair<ExplicitT, ExplicitT>,
                                                      std::pair<int, int> const&>::value, "");
@@ -60,4 +60,6 @@ int main() {
         static_assert( std::is_nothrow_constructible<std::pair<ImplicitNothrowT, ImplicitNothrowT>,
                                                      std::pair<int, int> const&>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/default.pass.cpp b/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/default.pass.cpp
index efd7fcb40e2cabb9db478d2ccb8aa3ec34feb299..a7f0f87645251f3d46d217709e1da28acea17e56 100644
--- a/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/default.pass.cpp
+++ b/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/default.pass.cpp
@@ -26,10 +26,12 @@ struct NonThrowingDefault {
   NonThrowingDefault() noexcept { }
 };
 
-int main() {
+int main(int, char**) {
 
     static_assert(!std::is_nothrow_default_constructible<std::pair<ThrowingDefault, ThrowingDefault>>::value, "");
     static_assert(!std::is_nothrow_default_constructible<std::pair<NonThrowingDefault, ThrowingDefault>>::value, "");
     static_assert(!std::is_nothrow_default_constructible<std::pair<ThrowingDefault, NonThrowingDefault>>::value, "");
     static_assert( std::is_nothrow_default_constructible<std::pair<NonThrowingDefault, NonThrowingDefault>>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/non_trivial_copy_move_ABI.pass.cpp b/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/non_trivial_copy_move_ABI.pass.cpp
index 076505b46a213b8e53574955208e9d13e01e8de0..00c1910a3ed17b949681a80c819a531564f2323f 100644
--- a/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/non_trivial_copy_move_ABI.pass.cpp
+++ b/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/non_trivial_copy_move_ABI.pass.cpp
@@ -158,7 +158,8 @@ void test_layout() {
     static_assert(offsetof(PairT, first) == 0, "");
 }
 
-int main() {
+int main(int, char**) {
     test_trivial();
     test_layout();
+    return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/pair.tuple_element.fail.cpp b/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/pair.tuple_element.fail.cpp
index fa5f2b6d5ef9c0ce9b2705fee77e950472217d62..5be63dd92c207c02b68eb06ad8123e5e0ded8e2b 100644
--- a/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/pair.tuple_element.fail.cpp
+++ b/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/pair.tuple_element.fail.cpp
@@ -14,11 +14,13 @@
 
 #include <utility>
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<int, double> P;
     std::tuple_element<2, P>::type foo; // expected-note {{requested here}}
         // expected-error-re@utility:* {{static_assert failed{{( due to requirement '2U[L]{0,2} < 2')?}} "Index out of bounds in std::tuple_element<std::pair<T1, T2>>"}}
     }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/piecewise.pass.cpp b/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/piecewise.pass.cpp
index 2c636182f41e6a37734bf09841a82df585c911a9..e4c953840129e168144018c9978f4c0bb90b9945 100644
--- a/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/piecewise.pass.cpp
+++ b/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/piecewise.pass.cpp
@@ -23,7 +23,7 @@
 #include "archetypes.hpp"
 
 
-int main() {
+int main(int, char**) {
     using NonThrowingConvert = NonThrowingTypes::ConvertingType;
     using ThrowingConvert = NonTrivialTypes::ConvertingType;
     static_assert(!std::is_nothrow_constructible<std::pair<ThrowingConvert, ThrowingConvert>,
@@ -34,4 +34,6 @@ int main() {
                                                  std::piecewise_construct_t, std::tuple<int, int>, std::tuple<long, long>>::value, "");
     static_assert( std::is_nothrow_constructible<std::pair<NonThrowingConvert, NonThrowingConvert>,
                                                  std::piecewise_construct_t, std::tuple<int, int>, std::tuple<long, long>>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/rv_pair_U_V.pass.cpp b/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/rv_pair_U_V.pass.cpp
index c64b92107df9efc9f7ab5c89c5a180ed8b7c74cd..8cc83f7bd0b3ed14c193d5562811fdf3ffadbe5a 100644
--- a/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/rv_pair_U_V.pass.cpp
+++ b/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/rv_pair_U_V.pass.cpp
@@ -38,7 +38,7 @@ struct ImplicitNothrowT {
     int value;
 };
 
-int main() {
+int main(int, char**) {
     { // explicit noexcept test
         static_assert(!std::is_nothrow_constructible<std::pair<ExplicitT, ExplicitT>,
                                                      std::pair<int, int>&&>::value, "");
@@ -59,4 +59,6 @@ int main() {
         static_assert( std::is_nothrow_constructible<std::pair<ImplicitNothrowT, ImplicitNothrowT>,
                                                      std::pair<int, int>&&>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/trivial_copy_move_ABI.pass.cpp b/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/trivial_copy_move_ABI.pass.cpp
index 39d3365aadecf5ffa1c51ed0a00ab13455fff607..1086011c37d82877c84f0cce959484c8d2f2e8a0 100644
--- a/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/trivial_copy_move_ABI.pass.cpp
+++ b/libcxx/test/libcxx/utilities/utility/pairs/pairs.pair/trivial_copy_move_ABI.pass.cpp
@@ -153,7 +153,8 @@ void test_layout() {
     static_assert(offsetof(PairT, first) == 0, "");
 }
 
-int main() {
+int main(int, char**) {
     test_trivial();
     test_layout();
+    return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/utility/version.pass.cpp b/libcxx/test/libcxx/utilities/utility/version.pass.cpp
index bd64d6e5aa2257d87fa8d77d595845c5647108b3..ca783db7fc13d78abaa44ccd2aa5654245598fbb 100644
--- a/libcxx/test/libcxx/utilities/utility/version.pass.cpp
+++ b/libcxx/test/libcxx/utilities/utility/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/variant/variant.variant/variant.helper/variant_alternative.fail.cpp b/libcxx/test/libcxx/utilities/variant/variant.variant/variant.helper/variant_alternative.fail.cpp
index 2249028285b0c045344f259e82c8a89dc1ee830e..fd23d5b9465d71bf3e72ca533df05b2b2444edca 100644
--- a/libcxx/test/libcxx/utilities/variant/variant.variant/variant.helper/variant_alternative.fail.cpp
+++ b/libcxx/test/libcxx/utilities/variant/variant.variant/variant.helper/variant_alternative.fail.cpp
@@ -25,11 +25,13 @@
 #include <cassert>
 
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::variant<int, double> T;
         std::variant_alternative<2, T>::type foo; // expected-note {{requested here}}
         // expected-error-re@variant:* {{static_assert failed{{( due to requirement '2U[L]{0,2} < sizeof...\(_Types\)')?}} "Index out of bounds in std::variant_alternative<>"}}
     }
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/variant/variant.variant/variant_size.pass.cpp b/libcxx/test/libcxx/utilities/variant/variant.variant/variant_size.pass.cpp
index 43cb302f95e0f1326bae1d71a86586886d20e64c..1bfe0e9fdff4d03904f5b85e4bcd7c575ee33e4b 100644
--- a/libcxx/test/libcxx/utilities/variant/variant.variant/variant_size.pass.cpp
+++ b/libcxx/test/libcxx/utilities/variant/variant.variant/variant_size.pass.cpp
@@ -59,10 +59,12 @@ void test_index_internals() {
   static_assert(std::__variant_npos<IndexT> == IndexLim::max(), "");
 }
 
-int main() {
+int main(int, char**) {
   test_index_type<unsigned char>();
   // This won't compile due to template depth issues.
   //test_index_type<unsigned short>();
   test_index_internals<unsigned char>();
   test_index_internals<unsigned short>();
+
+  return 0;
 }
diff --git a/libcxx/test/libcxx/utilities/variant/version.pass.cpp b/libcxx/test/libcxx/utilities/variant/version.pass.cpp
index c614ee472805240f8f7303fe71e9c187ede5fb31..3ef8ed50c9140b5deac6eca76fd01f6979f1b2ae 100644
--- a/libcxx/test/libcxx/utilities/variant/version.pass.cpp
+++ b/libcxx/test/libcxx/utilities/variant/version.pass.cpp
@@ -14,6 +14,8 @@
 #error _LIBCPP_VERSION not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/nothing_to_do.pass.cpp b/libcxx/test/nothing_to_do.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/nothing_to_do.pass.cpp
+++ b/libcxx/test/nothing_to_do.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.c.library/tested_elsewhere.pass.cpp b/libcxx/test/std/algorithms/alg.c.library/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/algorithms/alg.c.library/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.c.library/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.copy/copy.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.copy/copy.pass.cpp
index c18550a160aa88fc8bb2ac1339b1ad93a24049e1..9dcace7a03d1dd1dc8e22f674ef2162b96e63775 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.copy/copy.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.copy/copy.pass.cpp
@@ -46,7 +46,7 @@ test()
         assert(ia[i] == ib[i]);
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, output_iterator<int*> >();
     test<input_iterator<const int*>, input_iterator<int*> >();
@@ -86,4 +86,6 @@ int main()
 // #if TEST_STD_VER > 17
 //     static_assert(test_constexpr());
 // #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.copy/copy_backward.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.copy/copy_backward.pass.cpp
index bed5ff63629b9eb6759fb4c9cdc8e4fc2de0ccf5..3b20fbde5ba8c47693fbedc80f44ec0422269629 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.copy/copy_backward.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.copy/copy_backward.pass.cpp
@@ -49,7 +49,7 @@ test()
         assert(ia[i] == ib[i]);
 }
 
-int main()
+int main(int, char**)
 {
     test<bidirectional_iterator<const int*>, bidirectional_iterator<int*> >();
     test<bidirectional_iterator<const int*>, random_access_iterator<int*> >();
@@ -66,4 +66,6 @@ int main()
 // #if TEST_STD_VER > 17
 //     static_assert(test_constexpr());
 // #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.copy/copy_if.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.copy/copy_if.pass.cpp
index 3d29d62971c0756503e2fede816271b728070084..903bcbe6c25010336e6267da93fdf51aabcb684e 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.copy/copy_if.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.copy/copy_if.pass.cpp
@@ -53,7 +53,7 @@ test()
         assert(ib[i] % 3 == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, output_iterator<int*> >();
     test<input_iterator<const int*>, input_iterator<int*> >();
@@ -93,4 +93,6 @@ int main()
 // #if TEST_STD_VER > 17
 //     static_assert(test_constexpr());
 // #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.copy/copy_n.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.copy/copy_n.pass.cpp
index 540211752f3b6a8abbf67721cdaa0812ddeddcc9..2e181cfd49c747fd62654e6168e0b60e401f1cbe 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.copy/copy_n.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.copy/copy_n.pass.cpp
@@ -49,7 +49,7 @@ test()
         assert(ia[i] == ib[i]);
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, output_iterator<int*> >();
     test<input_iterator<const int*>, input_iterator<int*> >();
@@ -89,4 +89,6 @@ int main()
 // #if TEST_STD_VER > 17
 //     static_assert(test_constexpr());
 // #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.fill/fill.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.fill/fill.pass.cpp
index bc6a2c80e6f852c7a9493f90bd5112dd2851d79f..da56ec30f128b1b224bdc6ad67ca3efd32be1905 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.fill/fill.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.fill/fill.pass.cpp
@@ -56,7 +56,7 @@ test_int()
     assert(ia[3] == 1);
 }
 
-int main()
+int main(int, char**)
 {
     test_char<forward_iterator<char*> >();
     test_char<bidirectional_iterator<char*> >();
@@ -71,4 +71,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.fill/fill_n.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.fill/fill_n.pass.cpp
index a133ba63b5b711cbaa9ca561845350b4f961e11b..e774c915fa6457c4739a65de6c1259d6647bb5c8 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.fill/fill_n.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.fill/fill_n.pass.cpp
@@ -148,7 +148,7 @@ void test6()
 }
 
 
-int main()
+int main(int, char**)
 {
     test_char<forward_iterator<char*> >();
     test_char<bidirectional_iterator<char*> >();
@@ -170,4 +170,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.generate/generate.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.generate/generate.pass.cpp
index 4830ea5018bbefb03c07c1d80146135d347b2673..29d32d715674276910680856d338cc0d8643b42e 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.generate/generate.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.generate/generate.pass.cpp
@@ -51,7 +51,7 @@ test()
     assert(ia[3] == 1);
 }
 
-int main()
+int main(int, char**)
 {
     test<forward_iterator<int*> >();
     test<bidirectional_iterator<int*> >();
@@ -61,4 +61,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.generate/generate_n.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.generate/generate_n.pass.cpp
index 5b6712d44ad80e2dee151d9bd07bc66aea46f561..4ffdc648f62f377071cc7d6ef720226347a0a388 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.generate/generate_n.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.generate/generate_n.pass.cpp
@@ -74,7 +74,7 @@ test()
     test2<Iter, long double>();
 }
 
-int main()
+int main(int, char**)
 {
     test<forward_iterator<int*> >();
     test<bidirectional_iterator<int*> >();
@@ -84,4 +84,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.move/move.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.move/move.pass.cpp
index cab5e5a4e7c2211ab4bdf670b604d68e48c50e03..cdb126d4942ce6873947709158845654dfa1a156 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.move/move.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.move/move.pass.cpp
@@ -54,7 +54,7 @@ test1()
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, output_iterator<int*> >();
     test<input_iterator<const int*>, input_iterator<int*> >();
@@ -127,4 +127,6 @@ int main()
     test1<std::unique_ptr<int>*, random_access_iterator<std::unique_ptr<int>*> >();
     test1<std::unique_ptr<int>*, std::unique_ptr<int>*>();
 #endif // TEST_STD_VER >= 11
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.move/move_backward.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.move/move_backward.pass.cpp
index f9a6e77c815f0d4c2c96a05125f04836edcaefcd..365c1a1158d7e5d58edba2f816b1aac278597e0c 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.move/move_backward.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.move/move_backward.pass.cpp
@@ -54,7 +54,7 @@ test1()
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     test<bidirectional_iterator<const int*>, bidirectional_iterator<int*> >();
     test<bidirectional_iterator<const int*>, random_access_iterator<int*> >();
@@ -81,4 +81,6 @@ int main()
     test1<std::unique_ptr<int>*, random_access_iterator<std::unique_ptr<int>*> >();
     test1<std::unique_ptr<int>*, std::unique_ptr<int>*>();
 #endif // TEST_STD_VER >= 11
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.partitions/is_partitioned.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.partitions/is_partitioned.pass.cpp
index 460cc5e05880606beefceb2d8881eb9189346902..6c741490f1f25fe2c67da7cd7f400087142fb842 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.partitions/is_partitioned.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.partitions/is_partitioned.pass.cpp
@@ -35,7 +35,7 @@ TEST_CONSTEXPR bool test_constexpr() {
 #endif
 
 
-int main() {
+int main(int, char**) {
   {
     const int ia[] = {1, 2, 3, 4, 5, 6};
     unary_counting_predicate<is_odd, int> pred((is_odd()));
@@ -94,4 +94,6 @@ int main() {
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.partitions/partition.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.partitions/partition.pass.cpp
index c3749868b974ec3d742d5e4f0cf555b0899b1d1e..97af585b932c59bada66df438b6ccb1df3cc54b9 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.partitions/partition.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.partitions/partition.pass.cpp
@@ -93,9 +93,11 @@ test()
         assert(!is_odd()(*i));
 }
 
-int main()
+int main(int, char**)
 {
     test<bidirectional_iterator<int*> >();
     test<random_access_iterator<int*> >();
     test<int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.partitions/partition_copy.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.partitions/partition_copy.pass.cpp
index fcfcc7c796433cd6777c1402bd15dd64a198a3c8..26713634654101081abfe5e1389aeb8d44ae378c 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.partitions/partition_copy.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.partitions/partition_copy.pass.cpp
@@ -43,7 +43,7 @@ TEST_CONSTEXPR bool test_constexpr() {
     }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         const int ia[] = {1, 2, 3, 4, 6, 8, 5, 7};
@@ -68,4 +68,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.partitions/partition_point.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.partitions/partition_point.pass.cpp
index e6dd5c0414a5ddcba447faaf2f91ed2c2990a072..5da1b815043779c6193369cc888037a4044ba80a 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.partitions/partition_point.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.partitions/partition_point.pass.cpp
@@ -35,7 +35,7 @@ TEST_CONSTEXPR bool test_constexpr() {
 #endif
 
 
-int main()
+int main(int, char**)
 {
     {
         const int ia[] = {2, 4, 6, 8, 10};
@@ -89,4 +89,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.partitions/stable_partition.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.partitions/stable_partition.pass.cpp
index 7e886576f769218a2cf9451aeb54c188d3ba054b..0358f7030e8b3ec49c59acc1dbe80e3bc27c1e3b 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.partitions/stable_partition.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.partitions/stable_partition.pass.cpp
@@ -301,7 +301,7 @@ test1()
 
 #endif  // TEST_STD_VER >= 11
 
-int main()
+int main(int, char**)
 {
     test<bidirectional_iterator<std::pair<int,int>*> >();
     test<random_access_iterator<std::pair<int,int>*> >();
@@ -310,4 +310,6 @@ int main()
 #if TEST_STD_VER >= 11
     test1<bidirectional_iterator<std::unique_ptr<int>*> >();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.sample/sample.fail.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.sample/sample.fail.cpp
index a9aa64e4812db78972fd469fc333fb5ee4d8cdd5..c01104c0cfb546f4a3d82bd7b14af205bb316c77 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.sample/sample.fail.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.sample/sample.fail.cpp
@@ -32,9 +32,11 @@ template <class PopulationIterator, class SampleIterator> void test() {
                             SampleIterator(oa), os, g);
 }
 
-int main() {
+int main(int, char**) {
   // expected-error-re@algorithm:* {{static_assert failed{{( due to requirement '.*')?}} "SampleIterator must meet the requirements of RandomAccessIterator"}}
   // expected-error@algorithm:* 2 {{does not provide a subscript operator}}
   // expected-error@algorithm:* {{invalid operands}}
   test<input_iterator<int *>, output_iterator<int *> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.sample/sample.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.sample/sample.pass.cpp
index bfc71e779fa63958d92fa8b16a33103e3f58adea..40f2037f00e6f85eecad2c72be46c4db2c60e367 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.sample/sample.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.sample/sample.pass.cpp
@@ -136,7 +136,7 @@ void test_small_population() {
   }
 }
 
-int main() {
+int main(int, char**) {
   test<input_iterator, int, random_access_iterator, int>();
   test<forward_iterator, int, output_iterator, int>();
   test<forward_iterator, int, random_access_iterator, int>();
@@ -156,4 +156,6 @@ int main() {
   test_small_population<input_iterator, int, random_access_iterator, int>();
   test_small_population<forward_iterator, int, output_iterator, int>();
   test_small_population<forward_iterator, int, random_access_iterator, int>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.sample/sample.stable.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.sample/sample.stable.pass.cpp
index aa7c74788d74c030289b82ac43c4b72cd7673c15..58e6084626a9041ad4da21c3c6d9abd7c20c6a02 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.sample/sample.stable.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.sample/sample.stable.pass.cpp
@@ -48,7 +48,9 @@ void test_stability(bool expect_stable) {
   assert(expect_stable == !unstable);
 }
 
-int main() {
+int main(int, char**) {
   test_stability<forward_iterator<int *>, output_iterator<int *> >(true);
   test_stability<input_iterator<int *>, random_access_iterator<int *> >(false);
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle.pass.cpp
index 6ae7eb964a162984ebd9a9aad0a2a00a8788df8b..cb83cde936e0a848113ef55628f66d414918e52b 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle.pass.cpp
@@ -39,7 +39,7 @@ test_with_iterator()
 }
 
 
-int main()
+int main(int, char**)
 {
     int ia[]  = {1, 2, 3, 4};
     int ia1[] = {1, 4, 3, 2};
@@ -57,4 +57,5 @@ int main()
     test_with_iterator<random_access_iterator<int*> >();
     test_with_iterator<int*>();
 
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle_rand.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle_rand.pass.cpp
index ffdb098fc53b8f67aecb534cd0391343495f2184..dd5398dace15a347d8ddc1c31478cb523ce86d47 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle_rand.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle_rand.pass.cpp
@@ -51,8 +51,9 @@ test_with_iterator()
 }
 
 
-int main()
+int main(int, char**)
 {
     test_with_iterator<random_access_iterator<int*> >();
     test_with_iterator<int*>();
-}
\ No newline at end of file
+    return 0;
+}
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle_urng.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle_urng.pass.cpp
index 865eb48875102dacaddcf6956465ce039a1629cb..d5f162bced4161ff8965c51281f0c75e4907dd8d 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle_urng.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle_urng.pass.cpp
@@ -18,7 +18,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     int ia[] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
     int ia1[] = {2, 7, 1, 4, 3, 6, 5, 10, 9, 8};
@@ -31,4 +31,6 @@ int main()
     std::shuffle(ia, ia+sa, std::move(g));
     LIBCPP_ASSERT(std::equal(ia, ia+sa, ia2));
     assert(std::is_permutation(ia, ia+sa, ia2));
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.remove/remove.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.remove/remove.pass.cpp
index 3c7651189e89bc463df5a48e6986bae2e36a8b6f..ebacec5f49367a47962d7a5c621e600e6fa94543 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.remove/remove.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.remove/remove.pass.cpp
@@ -73,7 +73,7 @@ test1()
 }
 #endif // TEST_STD_VER >= 11
 
-int main()
+int main(int, char**)
 {
     test<forward_iterator<int*> >();
     test<bidirectional_iterator<int*> >();
@@ -90,4 +90,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.remove/remove_copy.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.remove/remove_copy.pass.cpp
index ab8d6d8866f6e112e3f63593b88f41a1d71f2f8a..8dedddb4c20bfb78c23efb62d8c29d96b420af75 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.remove/remove_copy.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.remove/remove_copy.pass.cpp
@@ -50,7 +50,7 @@ test()
     assert(ib[5] == 4);
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, output_iterator<int*> >();
     test<input_iterator<const int*>, forward_iterator<int*> >();
@@ -85,4 +85,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.remove/remove_copy_if.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.remove/remove_copy_if.pass.cpp
index c4ad12fa8cadb7bf27aa699cb0cc65a83ac5a536..7d10c6bd759ac751d5ea441b4a4a0424732f7a80 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.remove/remove_copy_if.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.remove/remove_copy_if.pass.cpp
@@ -55,7 +55,7 @@ test()
     assert(ib[5] == 4);
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, output_iterator<int*> >();
     test<input_iterator<const int*>, forward_iterator<int*> >();
@@ -90,4 +90,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.remove/remove_if.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.remove/remove_if.pass.cpp
index 35771b5a0222c27f626df971bb5ac2662a9c6fd1..637a91707d34c1903def9650bc48ba82ea1bf9f0 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.remove/remove_if.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.remove/remove_if.pass.cpp
@@ -88,7 +88,7 @@ test1()
 }
 #endif // TEST_STD_VER >= 11
 
-int main()
+int main(int, char**)
 {
     test<forward_iterator<int*> >();
     test<bidirectional_iterator<int*> >();
@@ -105,4 +105,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.replace/replace.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.replace/replace.pass.cpp
index 2f9dc692a89f21a731d8676f92819890cc7fd3d6..1e91fc968cb210eee3d4f849f01ff950d9af8602 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.replace/replace.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.replace/replace.pass.cpp
@@ -47,7 +47,7 @@ test()
     assert(ia[4] == 4);
 }
 
-int main()
+int main(int, char**)
 {
     test<forward_iterator<int*> >();
     test<bidirectional_iterator<int*> >();
@@ -57,4 +57,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.replace/replace_copy.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.replace/replace_copy.pass.cpp
index a7e38b92bbeb478143d1b2a090ebe67e1e44f673..da3fabf406b16914dc3fad5833d44e5e382ba507 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.replace/replace_copy.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.replace/replace_copy.pass.cpp
@@ -54,7 +54,7 @@ test()
     assert(ib[4] == 4);
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, output_iterator<int*> >();
     test<input_iterator<const int*>, forward_iterator<int*> >();
@@ -89,4 +89,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.replace/replace_copy_if.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.replace/replace_copy_if.pass.cpp
index 3daf1109ffcc8410737b489e2857e44901e0f064..26cbd705f49b8cfc7568959d20a58d2d85cddaef 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.replace/replace_copy_if.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.replace/replace_copy_if.pass.cpp
@@ -58,7 +58,7 @@ test()
     assert(ib[4] == 4);
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, output_iterator<int*> >();
     test<input_iterator<const int*>, forward_iterator<int*> >();
@@ -93,4 +93,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.replace/replace_if.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.replace/replace_if.pass.cpp
index d35927a1a9b1d84532c9c9a862faa0447887bb05..4f32b6e94a4132598a8804cfd4d638ad77a5405b 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.replace/replace_if.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.replace/replace_if.pass.cpp
@@ -50,7 +50,7 @@ test()
     assert(ia[4] == 4);
 }
 
-int main()
+int main(int, char**)
 {
     test<forward_iterator<int*> >();
     test<bidirectional_iterator<int*> >();
@@ -60,4 +60,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.reverse/reverse.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.reverse/reverse.pass.cpp
index d39da540582e9f4ad3c795ae62720405f56ea0a4..7838a0ca2f12b943b2187b938cbd9a8294009fa6 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.reverse/reverse.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.reverse/reverse.pass.cpp
@@ -51,9 +51,11 @@ test()
     assert(id[3] == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test<bidirectional_iterator<int*> >();
     test<random_access_iterator<int*> >();
     test<int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.reverse/reverse_copy.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.reverse/reverse_copy.pass.cpp
index 4758c4f1ebbed77d6621c8bfb563d4e247d3e83f..6967c446b75ddfa906be2fa673e0bc11259c34bf 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.reverse/reverse_copy.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.reverse/reverse_copy.pass.cpp
@@ -72,7 +72,7 @@ test()
     assert(jd[3] == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test<bidirectional_iterator<const int*>, output_iterator<int*> >();
     test<bidirectional_iterator<const int*>, forward_iterator<int*> >();
@@ -95,4 +95,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.rotate/rotate.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.rotate/rotate.pass.cpp
index a588b971c8161cea18b7d96918cda4dfad98c2c7..007faf685bfc27e58e7ad2f6b494a38ce39f2b8a 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.rotate/rotate.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.rotate/rotate.pass.cpp
@@ -419,7 +419,7 @@ test1()
 
 #endif  // TEST_STD_VER >= 11
 
-int main()
+int main(int, char**)
 {
     test<forward_iterator<int*> >();
     test<bidirectional_iterator<int*> >();
@@ -434,4 +434,6 @@ int main()
     test1<std::unique_ptr<int>*>();
 
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.rotate/rotate_copy.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.rotate/rotate_copy.pass.cpp
index 5f71e094015559f6244710577e46b0953343316e..d66bf8caad6e6ddfc1790efcc49beb5b9a281fe7 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.rotate/rotate_copy.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.rotate/rotate_copy.pass.cpp
@@ -128,7 +128,7 @@ test()
     assert(ib[3] == 3);
 }
 
-int main()
+int main(int, char**)
 {
     test<bidirectional_iterator<const int*>, output_iterator<int*> >();
     test<bidirectional_iterator<const int*>, forward_iterator<int*> >();
@@ -151,4 +151,6 @@ int main()
 // #if TEST_STD_VER > 17
 //    static_assert(test_constexpr());
 // #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.swap/iter_swap.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.swap/iter_swap.pass.cpp
index 182b17914c8ea34bd30bebc2333630c1e628d598..419bb4bbbffa74769f5e227a8f469059d4023b1b 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.swap/iter_swap.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.swap/iter_swap.pass.cpp
@@ -16,11 +16,13 @@
 #include <algorithm>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int i = 1;
     int j = 2;
     std::iter_swap(&i, &j);
     assert(i == 2);
     assert(j == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.swap/swap_ranges.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.swap/swap_ranges.pass.cpp
index 43cd4ce63f3a5f8bcba79702d9fb5ded8c458b3c..a47bbd24d95eaf26f8506915f1245b9d463ac68b 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.swap/swap_ranges.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.swap/swap_ranges.pass.cpp
@@ -105,7 +105,7 @@ void test2()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<forward_iterator<int*>, forward_iterator<int*> >();
     test<forward_iterator<int*>, bidirectional_iterator<int*> >();
@@ -150,4 +150,6 @@ int main()
 #endif // TEST_STD_VER >= 11
 
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.transform/binary_transform.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.transform/binary_transform.pass.cpp
index dc8101a25e0bde42e001485a364dd1d5a2eefcb3..ca7287bf24ba2192c5d297360690ee4e35387c4f 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.transform/binary_transform.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.transform/binary_transform.pass.cpp
@@ -56,7 +56,7 @@ test()
     assert(ib[4] == 1);
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, input_iterator<const int*>, output_iterator<int*> >();
     test<input_iterator<const int*>, input_iterator<const int*>, input_iterator<int*> >();
@@ -236,4 +236,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.transform/unary_transform.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.transform/unary_transform.pass.cpp
index 9fc25adc3309c9ec407aecb57d30b6e776d637ff..85c3868207bcf6ade64089746d217d429c63e35b 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.transform/unary_transform.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.transform/unary_transform.pass.cpp
@@ -57,7 +57,7 @@ test()
     assert(ib[4] == 5);
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, output_iterator<int*> >();
     test<input_iterator<const int*>, input_iterator<int*> >();
@@ -97,4 +97,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.unique/unique.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.unique/unique.pass.cpp
index 680633745df7ee04c54bde60318e1ee818a084b4..7046d6a2bd4086880c7f6322806cf865eec48de2 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.unique/unique.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.unique/unique.pass.cpp
@@ -181,7 +181,7 @@ test1()
 }
 #endif // TEST_STD_VER >= 11
 
-int main()
+int main(int, char**)
 {
     test<forward_iterator<int*> >();
     test<bidirectional_iterator<int*> >();
@@ -198,4 +198,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.unique/unique_copy.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.unique/unique_copy.pass.cpp
index 3c34a9a31601724a830f3a672bff89b509ae723a..ba533507cd98c1211384cbbf69ce42828fa7843a 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.unique/unique_copy.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.unique/unique_copy.pass.cpp
@@ -105,7 +105,7 @@ test()
     assert(ji[2] == 2);
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, output_iterator<int*> >();
     test<input_iterator<const int*>, forward_iterator<int*> >();
@@ -140,4 +140,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.unique/unique_copy_pred.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.unique/unique_copy_pred.pass.cpp
index b91c05e7652247948144b97994e0ffd44996a100..e8ebeaead8ccf0f9e5cd57aade2355873e71e40e 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.unique/unique_copy_pred.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.unique/unique_copy_pred.pass.cpp
@@ -133,7 +133,7 @@ test()
     assert(count_equal::count == si-1);
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, output_iterator<int*> >();
     test<input_iterator<const int*>, forward_iterator<int*> >();
@@ -168,4 +168,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.unique/unique_pred.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.unique/unique_pred.pass.cpp
index d48bb6a67436cada9b5d8fff1b61cf10fc1fdcaa..9f0c695e212dcc16dd03725c20a9e4d23b080438 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.unique/unique_pred.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.unique/unique_pred.pass.cpp
@@ -223,7 +223,7 @@ test1()
 }
 #endif // TEST_STD_VER >= 11
 
-int main()
+int main(int, char**)
 {
     test<forward_iterator<int*> >();
     test<bidirectional_iterator<int*> >();
@@ -240,4 +240,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/nothing_to_do.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/alg.adjacent.find/adjacent_find.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/alg.adjacent.find/adjacent_find.pass.cpp
index de03da4ba1d67febcb5fd16e1837a30a8e443f8b..6d57c5869ab704e7f23605c29c6d48e17564623a 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/alg.adjacent.find/adjacent_find.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/alg.adjacent.find/adjacent_find.pass.cpp
@@ -30,7 +30,7 @@ TEST_CONSTEXPR bool test_constexpr() {
     }
 #endif
 
-int main()
+int main(int, char**)
 {
     int ia[] = {0, 1, 2, 2, 0, 1, 2, 3};
     const unsigned sa = sizeof(ia)/sizeof(ia[0]);
@@ -47,4 +47,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/alg.adjacent.find/adjacent_find_pred.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/alg.adjacent.find/adjacent_find_pred.pass.cpp
index a542cb81f17c8e76e854a66ca882f7c73122b588..c80bc9fff83b64f42f8cf404679f5e4e231c01d9 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/alg.adjacent.find/adjacent_find_pred.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/alg.adjacent.find/adjacent_find_pred.pass.cpp
@@ -34,7 +34,7 @@ TEST_CONSTEXPR bool test_constexpr() {
     }
 #endif
 
-int main()
+int main(int, char**)
 {
     int ia[] = {0, 1, 2, 2, 0, 1, 2, 3};
     const unsigned sa = sizeof(ia)/sizeof(ia[0]);
@@ -54,4 +54,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/alg.all_of/all_of.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/alg.all_of/all_of.pass.cpp
index 61f6c2ceeded5680eb00459eb1d09f0fde7e794a..5c49878f6a49eae8726a1cbf1b173a6b766398c2 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/alg.all_of/all_of.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/alg.all_of/all_of.pass.cpp
@@ -36,7 +36,7 @@ TEST_CONSTEXPR bool test_constexpr() {
     }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         int ia[] = {2, 4, 6, 8};
@@ -58,4 +58,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/alg.any_of/any_of.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/alg.any_of/any_of.pass.cpp
index ea9f8a4c8d1192a5d878282f64624fa568ec9204..22ae581d64b018b4035c8d32971c086bcd6ce022 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/alg.any_of/any_of.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/alg.any_of/any_of.pass.cpp
@@ -36,7 +36,7 @@ TEST_CONSTEXPR bool test_constexpr() {
     }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         int ia[] = {2, 4, 6, 8};
@@ -66,4 +66,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/alg.count/count.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/alg.count/count.pass.cpp
index f2e93719e5a7554f3e1ebe1dd4f48eb5a378b42d..d864080df8d32eb8302c4fc23779eea47699bfbe 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/alg.count/count.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/alg.count/count.pass.cpp
@@ -29,7 +29,7 @@ TEST_CONSTEXPR bool test_constexpr() {
     }
 #endif
 
-int main()
+int main(int, char**)
 {
     int ia[] = {0, 1, 2, 2, 0, 1, 2, 3};
     const unsigned sa = sizeof(ia)/sizeof(ia[0]);
@@ -43,4 +43,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/alg.count/count_if.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/alg.count/count_if.pass.cpp
index 7f6be6a278fa0fc406bec314d1b2659085dce985..978f5fcdbe58ab2aaaaa929e5139fc668e1b7b13 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/alg.count/count_if.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/alg.count/count_if.pass.cpp
@@ -36,7 +36,7 @@ TEST_CONSTEXPR bool test_constexpr() {
     }
 #endif
 
-int main()
+int main(int, char**)
 {
     int ia[] = {0, 1, 2, 2, 0, 1, 2, 3};
     const unsigned sa = sizeof(ia)/sizeof(ia[0]);
@@ -53,4 +53,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/alg.equal/equal.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/alg.equal/equal.pass.cpp
index 81d46ce62f155ab0ce02f04e67c0895a624e600f..afd57491a40212cc6be92122329fb05f6899c8a8 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/alg.equal/equal.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/alg.equal/equal.pass.cpp
@@ -44,7 +44,7 @@ TEST_CONSTEXPR bool test_constexpr() {
 #endif
 
 
-int main()
+int main(int, char**)
 {
     int ia[] = {0, 1, 2, 3, 4, 5};
     const unsigned s = sizeof(ia)/sizeof(ia[0]);
@@ -88,4 +88,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/alg.equal/equal_pred.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/alg.equal/equal_pred.pass.cpp
index 03de33a6b3f8abff4563a06086a72cedf9a90bd4..2b9619b73ee7442562801fba2a55b9e252eeeafa 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/alg.equal/equal_pred.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/alg.equal/equal_pred.pass.cpp
@@ -58,7 +58,7 @@ bool counting_equals ( const T &a, const T &b ) {
     return a == b;
 }
 
-int main()
+int main(int, char**)
 {
     int ia[] = {0, 1, 2, 3, 4, 5};
     const unsigned s = sizeof(ia)/sizeof(ia[0]);
@@ -114,4 +114,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/alg.find.end/find_end.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/alg.find.end/find_end.pass.cpp
index 36633ee12f498cd5e8c62854a49cd4046ac213e0..3060528a8e899b9fb2302990b8c3ad0108958959 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/alg.find.end/find_end.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/alg.find.end/find_end.pass.cpp
@@ -62,7 +62,7 @@ test()
     assert(std::find_end(Iter1(ia), Iter1(ia), Iter2(b), Iter2(b+1)) == Iter1(ia));
 }
 
-int main()
+int main(int, char**)
 {
     test<forward_iterator<const int*>, forward_iterator<const int*> >();
     test<forward_iterator<const int*>, bidirectional_iterator<const int*> >();
@@ -77,4 +77,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/alg.find.end/find_end_pred.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/alg.find.end/find_end_pred.pass.cpp
index 2b3ca1b0404e27f971da9c99e0840ca812ccad8a..7358cf5f7010654f3d4d7a48cfdf4b3a8b9351a6 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/alg.find.end/find_end_pred.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/alg.find.end/find_end_pred.pass.cpp
@@ -92,7 +92,7 @@ test()
     assert(count_equal::count <= 0);
 }
 
-int main()
+int main(int, char**)
 {
     test<forward_iterator<const int*>, forward_iterator<const int*> >();
     test<forward_iterator<const int*>, bidirectional_iterator<const int*> >();
@@ -107,4 +107,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/alg.find.first.of/find_first_of.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/alg.find.first.of/find_first_of.pass.cpp
index 1df8c1b82708eb74b91c9663b7ceb4929e626800..04468f74103826472d8dcd70de8a2f9f698b808b 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/alg.find.first.of/find_first_of.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/alg.find.first.of/find_first_of.pass.cpp
@@ -38,7 +38,7 @@ TEST_CONSTEXPR bool test_constexpr() {
     }
 #endif
 
-int main()
+int main(int, char**)
 {
     int ia[] = {0, 1, 2, 3, 0, 1, 2, 3};
     const unsigned sa = sizeof(ia)/sizeof(ia[0]);
@@ -69,4 +69,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/alg.find.first.of/find_first_of_pred.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/alg.find.first.of/find_first_of_pred.pass.cpp
index cb64ee80acb93f8890c9830361d6962b81c03d30..3c32aee0e24610b7e94fa562e52ea6d7795c8ec2 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/alg.find.first.of/find_first_of_pred.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/alg.find.first.of/find_first_of_pred.pass.cpp
@@ -40,7 +40,7 @@ constexpr bool test_constexpr() {
     }
 #endif
 
-int main()
+int main(int, char**)
 {
     int ia[] = {0, 1, 2, 3, 0, 1, 2, 3};
     const unsigned sa = sizeof(ia)/sizeof(ia[0]);
@@ -75,4 +75,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/alg.find/find.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/alg.find/find.pass.cpp
index de7a4181c2d9cebba42f7aff2ad48889e4c255de..9dc265f18540c4ca68795b0ee5aa4fad346cceed 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/alg.find/find.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/alg.find/find.pass.cpp
@@ -29,7 +29,7 @@ TEST_CONSTEXPR bool test_constexpr() {
     }
 #endif
 
-int main()
+int main(int, char**)
 {
     int ia[] = {0, 1, 2, 3, 4, 5};
     const unsigned s = sizeof(ia)/sizeof(ia[0]);
@@ -42,4 +42,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/alg.find/find_if.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/alg.find/find_if.pass.cpp
index 7b0ae435a88129d3b256f08623fe9d8e5b6bed10..6151a55b8f6e17152cdf09070bb51805380f48a3 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/alg.find/find_if.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/alg.find/find_if.pass.cpp
@@ -37,7 +37,7 @@ TEST_CONSTEXPR bool test_constexpr() {
     }
 #endif
 
-int main()
+int main(int, char**)
 {
     int ia[] = {0, 1, 2, 3, 4, 5};
     const unsigned s = sizeof(ia)/sizeof(ia[0]);
@@ -53,4 +53,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/alg.find/find_if_not.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/alg.find/find_if_not.pass.cpp
index 90e952171d49b6ef71c58614fd4e4fda36c03f4c..36a75426999651f30e7d969740ec89d07b538b8e 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/alg.find/find_if_not.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/alg.find/find_if_not.pass.cpp
@@ -37,7 +37,7 @@ TEST_CONSTEXPR bool test_constexpr() {
     }
 #endif
 
-int main()
+int main(int, char**)
 {
     int ia[] = {0, 1, 2, 3, 4, 5};
     const unsigned s = sizeof(ia)/sizeof(ia[0]);
@@ -53,4 +53,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/alg.foreach/for_each_n.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/alg.foreach/for_each_n.pass.cpp
index b43acc13a5738758f6ca5ac44c14bdefe0d62b13..f4dcd2d577ad56ac30826ffdbe7745d639f41e45 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/alg.foreach/for_each_n.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/alg.foreach/for_each_n.pass.cpp
@@ -40,7 +40,7 @@ struct for_each_test
     void operator()(int& i) {++i; ++count;}
 };
 
-int main()
+int main(int, char**)
 {
     typedef input_iterator<int*> Iter;
     int ia[] = {0, 1, 2, 3, 4, 5};
@@ -76,4 +76,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/alg.foreach/test.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/alg.foreach/test.pass.cpp
index 66336b2f9fa6c7e185007128095ed9d8853c0a4e..4d129e75578a43ce8ec3b3da947b2995eb8ea1e3 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/alg.foreach/test.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/alg.foreach/test.pass.cpp
@@ -37,7 +37,7 @@ struct for_each_test
     void operator()(int& i) {++i; ++count;}
 };
 
-int main()
+int main(int, char**)
 {
     int ia[] = {0, 1, 2, 3, 4, 5};
     const unsigned s = sizeof(ia)/sizeof(ia[0]);
@@ -51,4 +51,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/alg.is_permutation/is_permutation.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/alg.is_permutation/is_permutation.pass.cpp
index 3173276d19090acccdd3dc5dc31f5e2ad39da85d..2a2c796caac01d7bf3ee6a6dc428ef94e8ec66a5 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/alg.is_permutation/is_permutation.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/alg.is_permutation/is_permutation.pass.cpp
@@ -35,7 +35,7 @@ TEST_CONSTEXPR bool test_constexpr() {
     }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         const int ia[] = {0};
@@ -618,4 +618,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/alg.is_permutation/is_permutation_pred.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/alg.is_permutation/is_permutation_pred.pass.cpp
index 914eccdcd0265005f8df7979a466ad29906b7bfa..ea4270ec4095bb3f706f660a2570ec067a81a448 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/alg.is_permutation/is_permutation_pred.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/alg.is_permutation/is_permutation_pred.pass.cpp
@@ -55,7 +55,7 @@ struct eq {
 };
 
 
-int main()
+int main(int, char**)
 {
     {
         const int ia[] = {0};
@@ -769,4 +769,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/alg.none_of/none_of.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/alg.none_of/none_of.pass.cpp
index c77ffb220b5040e993cf4d68aad70fb2e27b5156..f3a4fea9022da60e19dd724dce680014e21198ab 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/alg.none_of/none_of.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/alg.none_of/none_of.pass.cpp
@@ -36,7 +36,7 @@ TEST_CONSTEXPR bool test_constexpr() {
     }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         int ia[] = {2, 4, 6, 8};
@@ -66,4 +66,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/alg.search/search.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/alg.search/search.pass.cpp
index a3fedafdc852168786fa25438f9b19631d038a46..5aaa832ded024aca2bf3c0f7f7c1d4b00f2e154d 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/alg.search/search.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/alg.search/search.pass.cpp
@@ -95,7 +95,7 @@ test()
     assert(std::search(Iter1(ij), Iter1(ij+sj), Iter2(ik), Iter2(ik+sk)) == Iter1(ij+6));
 }
 
-int main()
+int main(int, char**)
 {
     test<forward_iterator<const int*>, forward_iterator<const int*> >();
     test<forward_iterator<const int*>, bidirectional_iterator<const int*> >();
@@ -121,4 +121,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/alg.search/search_n.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/alg.search/search_n.pass.cpp
index 50d710e673586810a93651bf2a219b75938ba946..3c86127f38b141d131dd64cd3553ec296e6f5dc9 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/alg.search/search_n.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/alg.search/search_n.pass.cpp
@@ -79,7 +79,7 @@ test()
     (void)std::search_n(Iter(ic), Iter(ic+sc), UserDefinedIntegral<unsigned>(0), 0);
 }
 
-int main()
+int main(int, char**)
 {
     test<forward_iterator<const int*> >();
     test<bidirectional_iterator<const int*> >();
@@ -88,4 +88,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/alg.search/search_n_pred.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/alg.search/search_n_pred.pass.cpp
index befa432bf28fb89c75a7ba8adfe6f7a8f20a0876..13568939099718544d7b64666c42773fe5487197 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/alg.search/search_n_pred.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/alg.search/search_n_pred.pass.cpp
@@ -158,7 +158,7 @@ test()
     count_equal::count = 0;
 }
 
-int main()
+int main(int, char**)
 {
     test<forward_iterator<const int*> >();
     test<bidirectional_iterator<const int*> >();
@@ -167,4 +167,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/alg.search/search_pred.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/alg.search/search_pred.pass.cpp
index e61f7f9f0f63eb68bbfc2702c258b3af236f7c31..f835d2f094581671ea4c1b748f6c7d35ab013032 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/alg.search/search_pred.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/alg.search/search_pred.pass.cpp
@@ -110,7 +110,7 @@ test()
     assert(count_equal::count <= sh*3);
 }
 
-int main()
+int main(int, char**)
 {
     test<forward_iterator<const int*>, forward_iterator<const int*> >();
     test<forward_iterator<const int*>, bidirectional_iterator<const int*> >();
@@ -125,4 +125,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/mismatch/mismatch.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/mismatch/mismatch.pass.cpp
index 74502d63156b2ab79a88611ee8ca5689d10956fb..72281b47fd77f23c356492cd4b469e51abd68a98 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/mismatch/mismatch.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/mismatch/mismatch.pass.cpp
@@ -58,7 +58,7 @@ TEST_CONSTEXPR bool test_constexpr() {
     }
 #endif
 
-int main()
+int main(int, char**)
 {
     int ia[] = {0, 1, 2, 2, 0, 1, 2, 3};
     const unsigned sa = sizeof(ia)/sizeof(ia[0]);
@@ -89,4 +89,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/mismatch/mismatch_pred.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/mismatch/mismatch_pred.pass.cpp
index 2b21daab0b8241d384a3b39c117e6a69d0c56613..15edec03a25ed35f90591430a3a1a96e05acdbf6 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/mismatch/mismatch_pred.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/mismatch/mismatch_pred.pass.cpp
@@ -68,7 +68,7 @@ TEST_CONSTEXPR bool test_constexpr() {
 #define HAS_FOUR_ITERATOR_VERSION
 #endif
 
-int main()
+int main(int, char**)
 {
     int ia[] = {0, 1, 2, 2, 0, 1, 2, 3};
     const unsigned sa = sizeof(ia)/sizeof(ia[0]);
@@ -114,4 +114,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.nonmodifying/nothing_to_do.pass.cpp b/libcxx/test/std/algorithms/alg.nonmodifying/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/algorithms/alg.nonmodifying/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.nonmodifying/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/binary.search/binary_search.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/binary.search/binary_search.pass.cpp
index 45c50ed0139e82051ecfc0ef415a6133ad93bca6..3d04d51614086e4cbbc8dfbc48b76ab0f8b20f0a 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/binary.search/binary_search.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/binary.search/binary_search.pass.cpp
@@ -61,7 +61,7 @@ test()
     test(Iter(v.data()), Iter(v.data()+v.size()), M, false);
 }
 
-int main()
+int main(int, char**)
 {
     int d[] = {0, 2, 4, 6};
     for (int* e = d; e <= d+4; ++e)
@@ -76,4 +76,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/binary.search/binary_search_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/binary.search/binary_search_comp.pass.cpp
index 75d7a64a3115c47a048f48e34d227c387ccbdccf..a447853d2da23cb7f3ff620498b0013b7a5fc579 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/binary.search/binary_search_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/binary.search/binary_search_comp.pass.cpp
@@ -62,7 +62,7 @@ test()
     test(Iter(v.data()), Iter(v.data()+v.size()), M, false);
 }
 
-int main()
+int main(int, char**)
 {
     int d[] = {6, 4, 2, 0};
     for (int* e = d; e <= d+4; ++e)
@@ -77,4 +77,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/equal.range/equal_range.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/equal.range/equal_range.pass.cpp
index e8b1598329609ff7b55f5f2969f51512c7ebfe45..e22bd5ad24541369fe6f010fa9e2201b175c0fcf 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/equal.range/equal_range.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/equal.range/equal_range.pass.cpp
@@ -69,7 +69,7 @@ test()
         test(Iter(v.data()), Iter(v.data()+v.size()), x);
 }
 
-int main()
+int main(int, char**)
 {
     int d[] = {0, 1, 2, 3};
     for (int* e = d; e <= d+4; ++e)
@@ -84,4 +84,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/equal.range/equal_range_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/equal.range/equal_range_comp.pass.cpp
index b7b43a829d1857c4d18919eff447a7af2d422852..ab36e70331a20544bd312d0614c96cf1db2c9d24 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/equal.range/equal_range_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/equal.range/equal_range_comp.pass.cpp
@@ -68,7 +68,7 @@ test()
         test(Iter(v.data()), Iter(v.data()+v.size()), x);
 }
 
-int main()
+int main(int, char**)
 {
     int d[] = {3, 2, 1, 0};
     for (int* e = d; e <= d+4; ++e)
@@ -83,4 +83,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/lower.bound/lower_bound.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/lower.bound/lower_bound.pass.cpp
index 8f99ed99e1daefdeb5927f3cd09eb6d3b6b5be30..ce9b71c0624246319b1243531e6cd505da91dcf5 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/lower.bound/lower_bound.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/lower.bound/lower_bound.pass.cpp
@@ -64,7 +64,7 @@ test()
         test(Iter(v.data()), Iter(v.data()+v.size()), x);
 }
 
-int main()
+int main(int, char**)
 {
     int d[] = {0, 1, 2, 3};
     for (int* e = d; e <= d+4; ++e)
@@ -79,4 +79,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/lower.bound/lower_bound_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/lower.bound/lower_bound_comp.pass.cpp
index 0190e0f2120d5b06e7c394840b4395e68e9da208..b9133028d9ade210401b873c1b3b1a03fbb9cac9 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/lower.bound/lower_bound_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/lower.bound/lower_bound_comp.pass.cpp
@@ -64,7 +64,7 @@ test()
         test(Iter(v.data()), Iter(v.data()+v.size()), x);
 }
 
-int main()
+int main(int, char**)
 {
     int d[] = {3, 2, 1, 0};
     for (int* e = d; e <= d+4; ++e)
@@ -79,4 +79,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/nothing_to_do.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/upper.bound/upper_bound.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/upper.bound/upper_bound.pass.cpp
index 6748b5ec4a8ea8689832cadde8ca788bc8f375e5..1f9babde5ec4b9d79beebf4e7aff5973315726f2 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/upper.bound/upper_bound.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/upper.bound/upper_bound.pass.cpp
@@ -61,7 +61,7 @@ test()
         test(Iter(v.data()), Iter(v.data()+v.size()), x);
 }
 
-int main()
+int main(int, char**)
 {
     int d[] = {0, 1, 2, 3};
     for (int* e = d; e <= d+4; ++e)
@@ -76,4 +76,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/upper.bound/upper_bound_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/upper.bound/upper_bound_comp.pass.cpp
index 5cbb01abee7e37c185d0d289fefe4f230f467197..86066a620bbe768341407a54ef363a354a7f5e4e 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/upper.bound/upper_bound_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.binary.search/upper.bound/upper_bound_comp.pass.cpp
@@ -64,7 +64,7 @@ test()
         test(Iter(v.data()), Iter(v.data()+v.size()), x);
 }
 
-int main()
+int main(int, char**)
 {
     int d[] = {3, 2, 1, 0};
     for (int* e = d; e <= d+4; ++e)
@@ -79,4 +79,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.clamp/clamp.comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.clamp/clamp.comp.pass.cpp
index 4fd10376fa22d3e0c92d54f49ddd6b3f290ff531..482af9ef33130797db78e730075a1f13759aad06 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.clamp/clamp.comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.clamp/clamp.comp.pass.cpp
@@ -38,7 +38,7 @@ test(const T& v, const T& lo, const T& hi, C c, const T& x)
     assert(&std::clamp(v, lo, hi, c) == &x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     int x = 0;
@@ -123,4 +123,6 @@ int main()
     static_assert(std::clamp(x, y, z, std::greater<T>()) == y, "" );
     static_assert(std::clamp(y, x, z, std::greater<T>()) == y, "" );
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.clamp/clamp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.clamp/clamp.pass.cpp
index 96c3b43df47c1a8914423d49caeb77d2bfacfa37..4066a39453e3fa8ab6aa38fe9e466b07eebd6372 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.clamp/clamp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.clamp/clamp.pass.cpp
@@ -36,7 +36,7 @@ test(const T& a, const T& lo, const T& hi, const T& x)
     assert(&std::clamp(a, lo, hi) == &x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     int x = 0;
@@ -121,4 +121,6 @@ int main()
     static_assert(std::clamp(x, y, z) == x, "" );
     static_assert(std::clamp(y, x, z) == x, "" );
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/is.heap/is_heap.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/is.heap/is_heap.pass.cpp
index ec78c10af77d7fd15fd315bdf1c9dfe6c01d6783..14b1d1754f22a65c50176646f6d069eb2a405415 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/is.heap/is_heap.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/is.heap/is_heap.pass.cpp
@@ -525,11 +525,13 @@ void test()
     assert(std::is_heap(i246, i246+7) == (std::is_heap_until(i246, i246+7) == i246+7));
 }
 
-int main()
+int main(int, char**)
 {
     test();
 
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/is.heap/is_heap_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/is.heap/is_heap_comp.pass.cpp
index b48db5423403b3b5188c4e2b7937677ee7a37f89..9e34458823976d5438ca00a6695138ac99acf7d5 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/is.heap/is_heap_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/is.heap/is_heap_comp.pass.cpp
@@ -526,11 +526,13 @@ void test()
     assert(std::is_heap(i246, i246+7, std::greater<int>()) == (std::is_heap_until(i246, i246+7, std::greater<int>()) == i246+7));
 }
 
-int main()
+int main(int, char**)
 {
     test();
 
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/is.heap/is_heap_until.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/is.heap/is_heap_until.pass.cpp
index 78eb5dd70d960fc89a592bd54ff84ad8ddff9225..b9bb3e1f5bfc499f355e2580ee26c959a1f8982e 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/is.heap/is_heap_until.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/is.heap/is_heap_until.pass.cpp
@@ -525,11 +525,13 @@ void test()
     assert(std::is_heap_until(i246, i246+7) == i246+7);
 }
 
-int main()
+int main(int, char**)
 {
     test();
 
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/is.heap/is_heap_until_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/is.heap/is_heap_until_comp.pass.cpp
index 21b21deca6489d5f2bf04355291c98b1f16e0d31..6002f662e1ac366eb411e3b8090aa413ddd4cbe3 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/is.heap/is_heap_until_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/is.heap/is_heap_until_comp.pass.cpp
@@ -526,11 +526,13 @@ void test()
     assert(std::is_heap_until(i246, i246+7, std::greater<int>()) == i246+6);
 }
 
-int main()
+int main(int, char**)
 {
     test();
 
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/make.heap/make_heap.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/make.heap/make_heap.pass.cpp
index 9d2bb6e231263b4c0da7b6087715747b1485a55f..3d862ca4f25ec96fbb38d495f214623646b1e916 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/make.heap/make_heap.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/make.heap/make_heap.pass.cpp
@@ -30,7 +30,7 @@ void test(int N)
     delete [] ia;
 }
 
-int main()
+int main(int, char**)
 {
     test(0);
     test(1);
@@ -38,4 +38,6 @@ int main()
     test(3);
     test(10);
     test(1000);
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/make.heap/make_heap_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/make.heap/make_heap_comp.pass.cpp
index 18fffd41ef94f066b9c973c9a4fcabfad9cfb8a6..0650f745479d07806ddb224bffa58a222e570348 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/make.heap/make_heap_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/make.heap/make_heap_comp.pass.cpp
@@ -74,7 +74,7 @@ void test(int N)
     delete [] ia;
 }
 
-int main()
+int main(int, char**)
 {
     test(0);
     test(1);
@@ -97,4 +97,6 @@ int main()
     delete [] ia;
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/nothing_to_do.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/pop.heap/pop_heap.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/pop.heap/pop_heap.pass.cpp
index 1f26f6d15b75d8e1d465d92a5a54ccdb8cdc26c7..2b434983cfcb36d6e253e9e137a1d92f13198b29 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/pop.heap/pop_heap.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/pop.heap/pop_heap.pass.cpp
@@ -35,7 +35,9 @@ void test(int N)
     delete [] ia;
 }
 
-int main()
+int main(int, char**)
 {
     test(1000);
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/pop.heap/pop_heap_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/pop.heap/pop_heap_comp.pass.cpp
index 74474be43c645faff7ebc8e33d56a914cf9627ac..63bd1520f465ebf9d9379ab7cfca84b2c2ce59b6 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/pop.heap/pop_heap_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/pop.heap/pop_heap_comp.pass.cpp
@@ -47,7 +47,7 @@ void test(int N)
     delete [] ia;
 }
 
-int main()
+int main(int, char**)
 {
     test(1000);
 
@@ -67,4 +67,6 @@ int main()
     delete [] ia;
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/push.heap/push_heap.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/push.heap/push_heap.pass.cpp
index d7f681edea1982bf18e23ef4240d5730d9d75999..7db79e3bc5dba2cc80906d9c738354c9bc287d94 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/push.heap/push_heap.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/push.heap/push_heap.pass.cpp
@@ -34,7 +34,9 @@ void test(int N)
     delete [] ia;
 }
 
-int main()
+int main(int, char**)
 {
     test(1000);
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/push.heap/push_heap_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/push.heap/push_heap_comp.pass.cpp
index 536a2687a5e7a9d4a2b78cc698433f895f70fb73..4a47f65bfc326ca1ad14f3770d2e0b0160e121db 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/push.heap/push_heap_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/push.heap/push_heap_comp.pass.cpp
@@ -45,7 +45,7 @@ void test(int N)
     delete [] ia;
 }
 
-int main()
+int main(int, char**)
 {
     test(1000);
 
@@ -64,4 +64,6 @@ int main()
     delete [] ia;
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/sort.heap/sort_heap.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/sort.heap/sort_heap.pass.cpp
index cae2c0d9b380bbb0d6d8c6a5c91095e142391f00..947affcf086e00800ce810d6d0c579de58494b93 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/sort.heap/sort_heap.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/sort.heap/sort_heap.pass.cpp
@@ -31,7 +31,7 @@ void test(int N)
     delete [] ia;
 }
 
-int main()
+int main(int, char**)
 {
     test(0);
     test(1);
@@ -39,4 +39,6 @@ int main()
     test(3);
     test(10);
     test(1000);
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/sort.heap/sort_heap_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/sort.heap/sort_heap_comp.pass.cpp
index 8bad526bb42fc9d7ba0c24d852f4a032680e18fc..151373b7181d56b8319779fb6df9b70bc6377c73 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/sort.heap/sort_heap_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/sort.heap/sort_heap_comp.pass.cpp
@@ -42,7 +42,7 @@ void test(int N)
     delete [] ia;
 }
 
-int main()
+int main(int, char**)
 {
     test(0);
     test(1);
@@ -64,4 +64,6 @@ int main()
     delete [] ia;
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.lex.comparison/lexicographical_compare.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.lex.comparison/lexicographical_compare.pass.cpp
index 096c58ce0b78b420ec5efff06516be737290a6cc..f421bfcb8bcd2dbb18c493f8b0a0218a9c473375 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.lex.comparison/lexicographical_compare.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.lex.comparison/lexicographical_compare.pass.cpp
@@ -46,7 +46,7 @@ test()
     assert(!std::lexicographical_compare(Iter1(ib+1), Iter1(ib+3),  Iter2(ia),   Iter2(ia+sa)));
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, input_iterator<const int*> >();
     test<input_iterator<const int*>, forward_iterator<const int*> >();
@@ -81,4 +81,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.lex.comparison/lexicographical_compare_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.lex.comparison/lexicographical_compare_comp.pass.cpp
index 50050c50aeb73f84026477a1cff990ed2f10a073..b0e0ee7d77ccaf13d1c6a7fea57abda26b5777c0 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.lex.comparison/lexicographical_compare_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.lex.comparison/lexicographical_compare_comp.pass.cpp
@@ -51,7 +51,7 @@ test()
     assert( std::lexicographical_compare(Iter1(ib+1), Iter1(ib+3),  Iter2(ia),   Iter2(ia+sa), c));
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, input_iterator<const int*> >();
     test<input_iterator<const int*>, forward_iterator<const int*> >();
@@ -86,4 +86,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.merge/inplace_merge.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.merge/inplace_merge.pass.cpp
index ebe7307289be9e12e2d2bf0ee7fcee63acc7b8d2..208221416812b5d408c7caee6234d801d7c55606 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.merge/inplace_merge.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.merge/inplace_merge.pass.cpp
@@ -96,7 +96,7 @@ test()
     test<Iter>(1000);
 }
 
-int main()
+int main(int, char**)
 {
     test<bidirectional_iterator<int*> >();
     test<random_access_iterator<int*> >();
@@ -107,4 +107,6 @@ int main()
     test<random_access_iterator<S*> >();
     test<S*>();
 #endif  // TEST_STD_VER >= 11
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.merge/inplace_merge_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.merge/inplace_merge_comp.pass.cpp
index ce26335cb792a07f804c29177c6108c2c7482db8..7ab5c0ca92295e3f9b47a28b4d2c18306e8cefe5 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.merge/inplace_merge_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.merge/inplace_merge_comp.pass.cpp
@@ -135,7 +135,7 @@ void test_PR31166 ()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<bidirectional_iterator<int*> >();
     test<random_access_iterator<int*> >();
@@ -167,4 +167,6 @@ int main()
 #endif  // TEST_STD_VER >= 11
 
     test_PR31166();
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.merge/merge.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.merge/merge.pass.cpp
index f373f04946b1b4d1e46492d7fbf50eae7b105f0d..6c6f0c46d446fc9c9bdbc5fc3effda8a4a2d2c8f 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.merge/merge.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.merge/merge.pass.cpp
@@ -89,7 +89,7 @@ test()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, input_iterator<const int*>, output_iterator<int*> >();
     test<input_iterator<const int*>, input_iterator<const int*>, forward_iterator<int*> >();
@@ -245,4 +245,6 @@ int main()
 //  Not yet - waiting on std::copy
 //     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.merge/merge_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.merge/merge_comp.pass.cpp
index c4fd0746b4b0f58d6b9c43baac16d428cc64a349..508a4f5ab7347492ec8e72df845bd8e9e23a86d3 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.merge/merge_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.merge/merge_comp.pass.cpp
@@ -100,7 +100,7 @@ test()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, input_iterator<const int*>, output_iterator<int*> >();
     test<input_iterator<const int*>, input_iterator<const int*>, forward_iterator<int*> >();
@@ -256,4 +256,6 @@ int main()
 //  Not yet - waiting on std::copy
 //     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/max.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/max.pass.cpp
index 773e14c466825da068b6c42b87ceecbb6224cd51..f52c72b14ceae0914764de5561a6cdb8511e0351 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/max.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/max.pass.cpp
@@ -24,7 +24,7 @@ test(const T& a, const T& b, const T& x)
     assert(&std::max(a, b) == &x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     int x = 0;
@@ -52,4 +52,6 @@ int main()
     static_assert(std::max(y, x) == x, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/max_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/max_comp.pass.cpp
index 8488f70033de474c3cff82bee567c1ec0e04b072..e554b3cd038e8ffcb1fc937a0e2c101878fb7cef 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/max_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/max_comp.pass.cpp
@@ -26,7 +26,7 @@ test(const T& a, const T& b, C c, const T& x)
     assert(&std::max(a, b, c) == &x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     int x = 0;
@@ -54,4 +54,6 @@ int main()
     static_assert(std::max(y, x, std::greater<int>()) == y, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/max_element.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/max_element.pass.cpp
index c6e9e634b1de86f04eca58b366d49de121e25cd2..cb5341ca047057125c9bc751ef9421d723a727ca 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/max_element.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/max_element.pass.cpp
@@ -71,7 +71,7 @@ void constexpr_test()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test<forward_iterator<const int*> >();
     test<bidirectional_iterator<const int*> >();
@@ -79,4 +79,6 @@ int main()
     test<const int*>();
 
     constexpr_test ();
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/max_element_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/max_element_comp.pass.cpp
index 0a7d6ef6a8a62cd06918c6d84b1910b828ca9ee7..fbcea97b636b280c8105826b2f60d611722624a5 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/max_element_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/max_element_comp.pass.cpp
@@ -91,7 +91,7 @@ void constexpr_test()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test<forward_iterator<const int*> >();
     test<bidirectional_iterator<const int*> >();
@@ -100,4 +100,6 @@ int main()
     test_eq();
 
     constexpr_test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/max_init_list.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/max_init_list.pass.cpp
index 560051e3167986225e21f41b006774b0e7da14a8..ff58ba479bdd295d97cb33061bc90bc25d91d82a 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/max_init_list.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/max_init_list.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     int i = std::max({2, 3, 1});
     assert(i == 3);
@@ -40,4 +40,6 @@ int main()
     static_assert(std::max({3, 2, 1}) == 3, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/max_init_list_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/max_init_list_comp.pass.cpp
index 0cdab3aa46a30cce4783b579213b96c81bfbcc7b..4042f48af5b68d90a38e8794e58e51585fdeef70 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/max_init_list_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/max_init_list_comp.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     int i = std::max({2, 3, 1}, std::greater<int>());
     assert(i == 1);
@@ -41,4 +41,6 @@ int main()
     static_assert(std::max({3, 2, 1}, std::greater<int>()) == 1, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/min.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/min.pass.cpp
index a34cb31e7bea52439c15c35f0589a2bc6627de0e..533077a55ae8ba6af147f673f1744efd18f6800c 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/min.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/min.pass.cpp
@@ -24,7 +24,7 @@ test(const T& a, const T& b, const T& x)
     assert(&std::min(a, b) == &x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     int x = 0;
@@ -52,4 +52,6 @@ int main()
     static_assert(std::min(y, x) == y, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/min_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/min_comp.pass.cpp
index 4a815dc0be955ea7bbdc0527ae8ce9e0aa55e2bf..4524fe47b802eabf30ed27847ee2e32057d70d0f 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/min_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/min_comp.pass.cpp
@@ -26,7 +26,7 @@ test(const T& a, const T& b, C c, const T& x)
     assert(&std::min(a, b, c) == &x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     int x = 0;
@@ -54,4 +54,6 @@ int main()
     static_assert(std::min(y, x, std::greater<int>()) == x, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/min_element.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/min_element.pass.cpp
index b208096d4df5e1492620a5d64846581fdf7ceeaa..151bfa8127aa23d6fe892afd7ff5549e31fdbe0b 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/min_element.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/min_element.pass.cpp
@@ -71,7 +71,7 @@ void constexpr_test()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test<forward_iterator<const int*> >();
     test<bidirectional_iterator<const int*> >();
@@ -79,4 +79,6 @@ int main()
     test<const int*>();
 
     constexpr_test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/min_element_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/min_element_comp.pass.cpp
index 89a9227bd2558693b900256f4b776f586b565efe..cada8b346c7a9161feba7d9f6b67f9234fde1761 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/min_element_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/min_element_comp.pass.cpp
@@ -91,7 +91,7 @@ void constexpr_test()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test<forward_iterator<const int*> >();
     test<bidirectional_iterator<const int*> >();
@@ -100,4 +100,6 @@ int main()
     test_eq();
 
     constexpr_test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/min_init_list.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/min_init_list.pass.cpp
index ba8da8dfa3987099c657e2a2f50f0b01c87a948e..1253e1a6fffad25fb84864917f0202df30b81028 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/min_init_list.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/min_init_list.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     int i = std::min({2, 3, 1});
     assert(i == 1);
@@ -40,4 +40,6 @@ int main()
     static_assert(std::min({3, 2, 1}) == 1, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/min_init_list_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/min_init_list_comp.pass.cpp
index e5f372367acdf596cf43e2879eab4abc9de13b08..b0bd5d492fda287d3a0662e9367fc00f0f6bc4f5 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/min_init_list_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/min_init_list_comp.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     int i = std::min({2, 3, 1}, std::greater<int>());
     assert(i == 3);
@@ -41,4 +41,6 @@ int main()
     static_assert(std::min({3, 2, 1}, std::greater<int>()) == 3, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/minmax.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/minmax.pass.cpp
index e7c2ffd5fdf97224b8009f17ecedfad0d817d62d..0dffd52742c1afffd179fb6f6c0d4bde82c2b820 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/minmax.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/minmax.pass.cpp
@@ -26,7 +26,7 @@ test(const T& a, const T& b, const T& x, const T& y)
     assert(&p.second == &y);
 }
 
-int main()
+int main(int, char**)
 {
     {
     int x = 0;
@@ -60,4 +60,6 @@ int main()
     static_assert(p2.second == x, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/minmax_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/minmax_comp.pass.cpp
index 8eb059119bf5047749edec2ad59d87b45a56c835..38ee5a96e52090d87fd20f5de2fda929df379698 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/minmax_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/minmax_comp.pass.cpp
@@ -29,7 +29,7 @@ test(const T& a, const T& b, C c, const T& x, const T& y)
 }
 
 
-int main()
+int main(int, char**)
 {
     {
     int x = 0;
@@ -63,4 +63,6 @@ int main()
     static_assert(p2.second == y, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/minmax_element.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/minmax_element.pass.cpp
index 14e7b0c06587bbf038f56f2a02a51afbbf879ff7..8b56ac180e507c5fb8f41bc501d393c82b390e1a 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/minmax_element.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/minmax_element.pass.cpp
@@ -89,7 +89,7 @@ void constexpr_test()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test<forward_iterator<const int*> >();
     test<bidirectional_iterator<const int*> >();
@@ -97,4 +97,6 @@ int main()
     test<const int*>();
 
    constexpr_test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/minmax_element_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/minmax_element_comp.pass.cpp
index ba7912ed3ded574035babafdf9f368e78fd928b9..3ecc02ce10e1e947bdb4e39c225b2899d49cc66c 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/minmax_element_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/minmax_element_comp.pass.cpp
@@ -96,7 +96,7 @@ void constexpr_test()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test<forward_iterator<const int*> >();
     test<bidirectional_iterator<const int*> >();
@@ -104,4 +104,6 @@ int main()
     test<const int*>();
 
     constexpr_test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/minmax_init_list.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/minmax_init_list.pass.cpp
index 477a0b893e0bf3bfdfba6904d0bbc62f4f3a26ca..e02b9fb38b3527799905ac8417e7b27708927e0b 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/minmax_init_list.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/minmax_init_list.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     assert((std::minmax({1, 2, 3}) == std::pair<int, int>(1, 3)));
     assert((std::minmax({1, 3, 2}) == std::pair<int, int>(1, 3)));
@@ -37,4 +37,6 @@ int main()
     static_assert((std::minmax({3, 2, 1}) == std::pair<int, int>(1, 3)), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/minmax_init_list_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/minmax_init_list_comp.pass.cpp
index 0b834257a55d4be9e63043e25553885443dd6648..efa0e92fb95010fcdec947cc4597e2405851537a 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/minmax_init_list_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/minmax_init_list_comp.pass.cpp
@@ -35,7 +35,7 @@ void test_all_equal(std::initializer_list<int> il)
     assert(pred.count() <= ((3 * il.size()) / 2));
 }
 
-int main()
+int main(int, char**)
 {
     assert((std::minmax({1, 2, 3}, std::greater<int>()) == std::pair<int, int>(3, 1)));
     assert((std::minmax({1, 3, 2}, std::greater<int>()) == std::pair<int, int>(3, 1)));
@@ -72,4 +72,6 @@ int main()
     static_assert((std::minmax({3, 2, 1}, std::greater<int>()) == std::pair<int, int>(3, 1)), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/requires_forward_iterator.fail.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/requires_forward_iterator.fail.cpp
index d19304458c4107fb6f7461c4dcde701c61d9a6ea..e048501753fd0d51417d6be8dc518b28a1d95183 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.min.max/requires_forward_iterator.fail.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.min.max/requires_forward_iterator.fail.cpp
@@ -16,7 +16,7 @@
 
 #include "test_iterators.h"
 
-int main() {
+int main(int, char**) {
   int arr[] = {1, 2, 3};
   const int *b = std::begin(arr), *e = std::end(arr);
   typedef input_iterator<const int*> Iter;
@@ -33,4 +33,6 @@ int main() {
     std::minmax_element(Iter(b), Iter(e));
   }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.nth.element/nth_element.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.nth.element/nth_element.pass.cpp
index b331239f1f4fd82c5a856703133cdc203c1e493b..abde620d03876f5c4a7aed49b5107b7a1bfa3548 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.nth.element/nth_element.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.nth.element/nth_element.pass.cpp
@@ -50,7 +50,7 @@ test(int N)
     test_one(N, N-1);
 }
 
-int main()
+int main(int, char**)
 {
     int d = 0;
     std::nth_element(&d, &d, &d);
@@ -62,4 +62,6 @@ int main()
     test(997);
     test(1000);
     test(1009);
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.nth.element/nth_element_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.nth.element/nth_element_comp.pass.cpp
index 5f46394278caf2c8869e78eb5fa68684d32338c7..980b2b9881b83de5f5f2ac2d9600d4c3e017d06d 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.nth.element/nth_element_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.nth.element/nth_element_comp.pass.cpp
@@ -63,7 +63,7 @@ test(int N)
     test_one(N, N-1);
 }
 
-int main()
+int main(int, char**)
 {
     int d = 0;
     std::nth_element(&d, &d, &d);
@@ -85,4 +85,6 @@ int main()
     assert(static_cast<std::size_t>(*v[v.size()/2]) == v.size()/2);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.permutation.generators/next_permutation.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.permutation.generators/next_permutation.pass.cpp
index 74cd21c5c5b33479f6793df690a2080d0a558227..62d5b42e23e00eccfbb2ebbe36a008684ef30519 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.permutation.generators/next_permutation.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.permutation.generators/next_permutation.pass.cpp
@@ -57,9 +57,11 @@ test()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<bidirectional_iterator<int*> >();
     test<random_access_iterator<int*> >();
     test<int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.permutation.generators/next_permutation_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.permutation.generators/next_permutation_comp.pass.cpp
index fed1a2c51ebdd33a49400ac33bd010544f6a3d6c..4416ed1e4a888cf96016a71738e583517cdba910 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.permutation.generators/next_permutation_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.permutation.generators/next_permutation_comp.pass.cpp
@@ -59,9 +59,11 @@ test()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<bidirectional_iterator<int*> >();
     test<random_access_iterator<int*> >();
     test<int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.permutation.generators/prev_permutation.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.permutation.generators/prev_permutation.pass.cpp
index 6f11ebda07772d4abbaabccdba01c0bd95f8629a..044a6444ab0127cd6a8e063429f862f09f6d90d7 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.permutation.generators/prev_permutation.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.permutation.generators/prev_permutation.pass.cpp
@@ -57,9 +57,11 @@ test()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<bidirectional_iterator<int*> >();
     test<random_access_iterator<int*> >();
     test<int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.permutation.generators/prev_permutation_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.permutation.generators/prev_permutation_comp.pass.cpp
index 1c78728a53d49ea00e57a4e44631eed80ade98bb..760daae36baa258234e990c8120d4692c4a5eb52 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.permutation.generators/prev_permutation_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.permutation.generators/prev_permutation_comp.pass.cpp
@@ -59,9 +59,11 @@ test()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<bidirectional_iterator<int*> >();
     test<random_access_iterator<int*> >();
     test<int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/includes/includes.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/includes/includes.pass.cpp
index 72f80df566d050daef223f5506186ed13d693397..f8e8884085def7d5e1dac63137d3ec0ec264c065 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/includes/includes.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/includes/includes.pass.cpp
@@ -62,7 +62,7 @@ test()
     assert(!std::includes(Iter1(ia), Iter1(ia+sa), Iter2(id), Iter2(id+4)));
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, input_iterator<const int*> >();
     test<input_iterator<const int*>, forward_iterator<const int*> >();
@@ -97,4 +97,6 @@ int main()
 #if TEST_STD_VER > 17
    static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/includes/includes_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/includes/includes_comp.pass.cpp
index 5d959a0a8558355f1603e7135dffc9dba150d369..48bafcb3a84cba6fab3a4e0796e99a5a18ca2d51 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/includes/includes_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/includes/includes_comp.pass.cpp
@@ -65,7 +65,7 @@ test()
     assert(!std::includes(Iter1(ia), Iter1(ia+sa), Iter2(id), Iter2(id+4), std::less<int>()));
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, input_iterator<const int*> >();
     test<input_iterator<const int*>, forward_iterator<const int*> >();
@@ -100,4 +100,6 @@ int main()
 #if TEST_STD_VER > 17
    static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/nothing_to_do.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.difference/set_difference.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.difference/set_difference.pass.cpp
index 576b2889aabd58f9512b00ef3d1388900796b151..4d1f537b7f157766fb904bf2a20361c12db08f2d 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.difference/set_difference.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.difference/set_difference.pass.cpp
@@ -45,7 +45,7 @@ test()
     assert(std::lexicographical_compare(ic, base(ce), irr, irr+srr) == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, input_iterator<const int*>, output_iterator<int*> >();
     test<input_iterator<const int*>, input_iterator<const int*>, forward_iterator<int*> >();
@@ -196,4 +196,6 @@ int main()
     test<const int*, const int*, bidirectional_iterator<int*> >();
     test<const int*, const int*, random_access_iterator<int*> >();
     test<const int*, const int*, int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.difference/set_difference_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.difference/set_difference_comp.pass.cpp
index 8b2f1c0494c2560d594ae07521ed82e19cac6f44..2597174c6068f7ef08f82b0953e504db61d817c6 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.difference/set_difference_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.difference/set_difference_comp.pass.cpp
@@ -47,7 +47,7 @@ test()
     assert(std::lexicographical_compare(ic, base(ce), irr, irr+srr) == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, input_iterator<const int*>, output_iterator<int*> >();
     test<input_iterator<const int*>, input_iterator<const int*>, forward_iterator<int*> >();
@@ -198,4 +198,6 @@ int main()
     test<const int*, const int*, bidirectional_iterator<int*> >();
     test<const int*, const int*, random_access_iterator<int*> >();
     test<const int*, const int*, int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.intersection/set_intersection.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.intersection/set_intersection.pass.cpp
index 84b5aa0a96c96fd2e4137540ad7b052f21972814..08e08f672aed04c8e17970024ab005fa4cc63f3d 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.intersection/set_intersection.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.intersection/set_intersection.pass.cpp
@@ -62,7 +62,7 @@ test()
     assert(std::lexicographical_compare(ic, base(ce), ir, ir+sr) == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, input_iterator<const int*>, output_iterator<int*> >();
     test<input_iterator<const int*>, input_iterator<const int*>, forward_iterator<int*> >();
@@ -217,4 +217,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.intersection/set_intersection_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.intersection/set_intersection_comp.pass.cpp
index 0511d77f8442b0998518e30aefed794e3a716765..acdd7b0191b797cf87aa4d987e8deb321ad9eadb 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.intersection/set_intersection_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.intersection/set_intersection_comp.pass.cpp
@@ -65,7 +65,7 @@ test()
     assert(std::lexicographical_compare(ic, base(ce), ir, ir+sr) == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, input_iterator<const int*>, output_iterator<int*> >();
     test<input_iterator<const int*>, input_iterator<const int*>, forward_iterator<int*> >();
@@ -220,4 +220,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.symmetric.difference/set_symmetric_difference.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.symmetric.difference/set_symmetric_difference.pass.cpp
index e869169b39bdf098ce3701f6cf59a602e7f435e5..c74d6623bc5fb32e999f58e711ff47820eae0577 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.symmetric.difference/set_symmetric_difference.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.symmetric.difference/set_symmetric_difference.pass.cpp
@@ -44,7 +44,7 @@ test()
     assert(std::lexicographical_compare(ic, base(ce), ir, ir+sr) == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, input_iterator<const int*>, output_iterator<int*> >();
     test<input_iterator<const int*>, input_iterator<const int*>, forward_iterator<int*> >();
@@ -195,4 +195,6 @@ int main()
     test<const int*, const int*, bidirectional_iterator<int*> >();
     test<const int*, const int*, random_access_iterator<int*> >();
     test<const int*, const int*, int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.symmetric.difference/set_symmetric_difference_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.symmetric.difference/set_symmetric_difference_comp.pass.cpp
index a429e59bbc6a63722a5eb8bf4a7c65fc58a115d6..99e75b1224a9f486062cfd884b9cb0546825c8bb 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.symmetric.difference/set_symmetric_difference_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.symmetric.difference/set_symmetric_difference_comp.pass.cpp
@@ -48,7 +48,7 @@ test()
     assert(std::lexicographical_compare(ic, base(ce), ir, ir+sr) == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, input_iterator<const int*>, output_iterator<int*> >();
     test<input_iterator<const int*>, input_iterator<const int*>, forward_iterator<int*> >();
@@ -199,4 +199,6 @@ int main()
     test<const int*, const int*, bidirectional_iterator<int*> >();
     test<const int*, const int*, random_access_iterator<int*> >();
     test<const int*, const int*, int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.union/set_union.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.union/set_union.pass.cpp
index bc517543815c48850ac59bca34ee9c8ad44d6f65..827c2c1900107847fd94ae2d364d0039d1ae1436 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.union/set_union.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.union/set_union.pass.cpp
@@ -43,7 +43,7 @@ test()
     assert(std::lexicographical_compare(ic, base(ce), ir, ir+sr) == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, input_iterator<const int*>, output_iterator<int*> >();
     test<input_iterator<const int*>, input_iterator<const int*>, forward_iterator<int*> >();
@@ -194,4 +194,6 @@ int main()
     test<const int*, const int*, bidirectional_iterator<int*> >();
     test<const int*, const int*, random_access_iterator<int*> >();
     test<const int*, const int*, int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.union/set_union_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.union/set_union_comp.pass.cpp
index 8ce76754c4640c411eb66675421d7427a72523d8..c8d1d28828c2677a81ec6c2e7a9bba19f0cf7cd4 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.union/set_union_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.union/set_union_comp.pass.cpp
@@ -45,7 +45,7 @@ test()
     assert(std::lexicographical_compare(ic, base(ce), ir, ir+sr) == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, input_iterator<const int*>, output_iterator<int*> >();
     test<input_iterator<const int*>, input_iterator<const int*>, forward_iterator<int*> >();
@@ -196,4 +196,6 @@ int main()
     test<const int*, const int*, bidirectional_iterator<int*> >();
     test<const int*, const int*, random_access_iterator<int*> >();
     test<const int*, const int*, int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.union/set_union_move.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.union/set_union_move.pass.cpp
index 7af3f23ff435754804720d4bb8be89997da4fadb..45bd455bb8191d580f347784ac77c171f2d4b46e 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.union/set_union_move.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.set.operations/set.union/set_union_move.pass.cpp
@@ -28,7 +28,7 @@
 #include "MoveOnly.h"
 
 
-int main()
+int main(int, char**)
 {
     std::vector<MoveOnly> lhs, rhs;
     lhs.push_back(MoveOnly(2));
@@ -42,4 +42,6 @@ int main()
 
     assert(res.size() == 1);
     assert(res[0].get() == 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.sort/is.sorted/is_sorted.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.sort/is.sorted/is_sorted.pass.cpp
index f500aeb0c5a125bc4633c954bd1cdbf6ce3483d4..6e2ea5f3aed233d0d6491f8ce9f63727574591ad 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.sort/is.sorted/is_sorted.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.sort/is.sorted/is_sorted.pass.cpp
@@ -182,7 +182,7 @@ test()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<forward_iterator<const int*> >();
     test<bidirectional_iterator<const int*> >();
@@ -192,4 +192,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.sort/is.sorted/is_sorted_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.sort/is.sorted/is_sorted_comp.pass.cpp
index 5a490977b6b9c86c093df68f8fc93e675f448ba2..c5624d994d6c44d149f6e2017b3000da2f72d2d4 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.sort/is.sorted/is_sorted_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.sort/is.sorted/is_sorted_comp.pass.cpp
@@ -183,7 +183,7 @@ test()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<forward_iterator<const int*> >();
     test<bidirectional_iterator<const int*> >();
@@ -193,4 +193,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.sort/is.sorted/is_sorted_until.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.sort/is.sorted/is_sorted_until.pass.cpp
index 726772c5b783213be3dcdac55223f474c68e2ec9..4396a4fc820255118874d009277ed5a591c76e22 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.sort/is.sorted/is_sorted_until.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.sort/is.sorted/is_sorted_until.pass.cpp
@@ -182,7 +182,7 @@ test()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<forward_iterator<const int*> >();
     test<bidirectional_iterator<const int*> >();
@@ -192,4 +192,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.sort/is.sorted/is_sorted_until_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.sort/is.sorted/is_sorted_until_comp.pass.cpp
index cb20c0cbad46e1965dc1c1453ac30ced55e9bc1c..48696cf08385282cb1f877a7d6aed5a6b0ef4fdc 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.sort/is.sorted/is_sorted_until_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.sort/is.sorted/is_sorted_until_comp.pass.cpp
@@ -183,7 +183,7 @@ test()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<forward_iterator<const int*> >();
     test<bidirectional_iterator<const int*> >();
@@ -193,4 +193,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.sort/nothing_to_do.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.sort/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.sort/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.sort/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.sort/partial.sort.copy/partial_sort_copy.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.sort/partial.sort.copy/partial_sort_copy.pass.cpp
index ddea611b15824509ba6841c3b2d094a5cab76c72..45a6fef6701d1074d6f8e36d38ea7019d8e3dfa6 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.sort/partial.sort.copy/partial_sort_copy.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.sort/partial.sort.copy/partial_sort_copy.pass.cpp
@@ -75,7 +75,7 @@ test()
     test_larger_sorts<Iter>(1009);
 }
 
-int main()
+int main(int, char**)
 {
     int i = 0;
     std::partial_sort_copy(&i, &i, &i, &i+5);
@@ -85,4 +85,6 @@ int main()
     test<bidirectional_iterator<const int*> >();
     test<random_access_iterator<const int*> >();
     test<const int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.sort/partial.sort.copy/partial_sort_copy_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.sort/partial.sort.copy/partial_sort_copy_comp.pass.cpp
index d3e30b9d04bba6cf593d438daa58894084d0f506..a1c2b0f9c8a3a5834523f3b0d59a2b2696ec5cee 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.sort/partial.sort.copy/partial_sort_copy_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.sort/partial.sort.copy/partial_sort_copy_comp.pass.cpp
@@ -79,7 +79,7 @@ test()
     test_larger_sorts<Iter>(1009);
 }
 
-int main()
+int main(int, char**)
 {
     int i = 0;
     std::partial_sort_copy(&i, &i, &i, &i+5);
@@ -89,4 +89,6 @@ int main()
     test<bidirectional_iterator<const int*> >();
     test<random_access_iterator<const int*> >();
     test<const int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.sort/partial.sort/partial_sort.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.sort/partial.sort/partial_sort.pass.cpp
index 7e52c5747f8fd867846275e6632e745ecad9a617..b41eb12d6aaf56eb87e7acb0a282dcff92f77cde 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.sort/partial.sort/partial_sort.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.sort/partial.sort/partial_sort.pass.cpp
@@ -53,7 +53,7 @@ test_larger_sorts(int N)
     test_larger_sorts(N, N);
 }
 
-int main()
+int main(int, char**)
 {
     int i = 0;
     std::partial_sort(&i, &i, &i);
@@ -66,4 +66,6 @@ int main()
     test_larger_sorts(997);
     test_larger_sorts(1000);
     test_larger_sorts(1009);
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.sort/partial.sort/partial_sort_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.sort/partial.sort/partial_sort_comp.pass.cpp
index e1143f592f930ab762a282d150edb0b2d24805d7..f50d04005a40881621b9ec3136eba932043e21c0 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.sort/partial.sort/partial_sort_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.sort/partial.sort/partial_sort_comp.pass.cpp
@@ -66,7 +66,7 @@ test_larger_sorts(int N)
     test_larger_sorts(N, N);
 }
 
-int main()
+int main(int, char**)
 {
     {
     int i = 0;
@@ -92,4 +92,6 @@ int main()
         assert(*v[i] == i);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.sort/sort/sort.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.sort/sort/sort.pass.cpp
index c65f13c0748e2bf9ccb08a15869fffa03a3b9116..8f2845732cc922ae951f6c420f2db0bded28e705 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.sort/sort/sort.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.sort/sort/sort.pass.cpp
@@ -130,7 +130,7 @@ test_larger_sorts(int N)
     test_larger_sorts(N, N);
 }
 
-int main()
+int main(int, char**)
 {
     // test null range
     int d = 0;
@@ -152,4 +152,6 @@ int main()
     test_larger_sorts(997);
     test_larger_sorts(1000);
     test_larger_sorts(1009);
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.sort/sort/sort_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.sort/sort/sort_comp.pass.cpp
index e6896bea41649141d7fd2e60bcf94114fc529c12..832d190ce47b96d662296727f9e4a7910d130abd 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.sort/sort/sort_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.sort/sort/sort_comp.pass.cpp
@@ -30,7 +30,7 @@ struct indirect_less
         {return *x < *y;}
 };
 
-int main()
+int main(int, char**)
 {
     {
     std::vector<int> v(1000);
@@ -53,4 +53,6 @@ int main()
     assert(*v[2] == 2);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.sort/stable.sort/stable_sort.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.sort/stable.sort/stable_sort.pass.cpp
index 9341d699410cf55239e1a4dd8d6a8f1741da836b..c433baab44a6af08b6e939df8c968847bcc656ea 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.sort/stable.sort/stable_sort.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.sort/stable.sort/stable_sort.pass.cpp
@@ -130,7 +130,7 @@ test_larger_sorts(int N)
     test_larger_sorts(N, N);
 }
 
-int main()
+int main(int, char**)
 {
     // test null range
     int d = 0;
@@ -152,4 +152,6 @@ int main()
     test_larger_sorts(997);
     test_larger_sorts(1000);
     test_larger_sorts(1009);
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/alg.sort/stable.sort/stable_sort_comp.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/alg.sort/stable.sort/stable_sort_comp.pass.cpp
index 6c5dcabfe323d026e1d344ac30799c1e9e896dee..8da2b964b7e3703cad3cf8b8a80b364dca5c96d4 100644
--- a/libcxx/test/std/algorithms/alg.sorting/alg.sort/stable.sort/stable_sort_comp.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/alg.sort/stable.sort/stable_sort_comp.pass.cpp
@@ -66,7 +66,7 @@ void test()
     assert(std::is_sorted(v.begin(), v.end()));
 }
 
-int main()
+int main(int, char**)
 {
     test();
 
@@ -82,4 +82,6 @@ int main()
     assert(*v[2] == 2);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/alg.sorting/nothing_to_do.pass.cpp b/libcxx/test/std/algorithms/alg.sorting/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/algorithms/alg.sorting/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.sorting/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/algorithms/algorithms.general/nothing_to_do.pass.cpp b/libcxx/test/std/algorithms/algorithms.general/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/algorithms/algorithms.general/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/algorithms/algorithms.general/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.fences/atomic_signal_fence.pass.cpp b/libcxx/test/std/atomics/atomics.fences/atomic_signal_fence.pass.cpp
index ae4af5c9750192df685594a8ad70401abb4e884e..bf5325940e41c52e96f5122c3c99ead49f5199d7 100644
--- a/libcxx/test/std/atomics/atomics.fences/atomic_signal_fence.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.fences/atomic_signal_fence.pass.cpp
@@ -14,7 +14,9 @@
 
 #include <atomic>
 
-int main()
+int main(int, char**)
 {
     std::atomic_signal_fence(std::memory_order_seq_cst);
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.fences/atomic_thread_fence.pass.cpp b/libcxx/test/std/atomics/atomics.fences/atomic_thread_fence.pass.cpp
index 91aeff28238234d45eab1cb54daaf6ff8c891412..d237f2de118783bf2c70179ad338d5303add84ef 100644
--- a/libcxx/test/std/atomics/atomics.fences/atomic_thread_fence.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.fences/atomic_thread_fence.pass.cpp
@@ -14,7 +14,9 @@
 
 #include <atomic>
 
-int main()
+int main(int, char**)
 {
     std::atomic_thread_fence(std::memory_order_seq_cst);
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.flag/atomic_flag_clear.pass.cpp b/libcxx/test/std/atomics/atomics.flag/atomic_flag_clear.pass.cpp
index 846d86e7a6bff2e46ce5154195fd30c45565cc44..23cb3d2b6fa401cea7560a0fd9c3951d1d53d644 100644
--- a/libcxx/test/std/atomics/atomics.flag/atomic_flag_clear.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.flag/atomic_flag_clear.pass.cpp
@@ -18,7 +18,7 @@
 #include <atomic>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::atomic_flag f;
@@ -34,4 +34,6 @@ int main()
         atomic_flag_clear(&f);
         assert(f.test_and_set() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.flag/atomic_flag_clear_explicit.pass.cpp b/libcxx/test/std/atomics/atomics.flag/atomic_flag_clear_explicit.pass.cpp
index 104c22b57c07cd7ea713521de999c94873e2f8bd..d87291297eed5a4dc375d2c96399bb1fb1d808ac 100644
--- a/libcxx/test/std/atomics/atomics.flag/atomic_flag_clear_explicit.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.flag/atomic_flag_clear_explicit.pass.cpp
@@ -18,7 +18,7 @@
 #include <atomic>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::atomic_flag f; // uninitialized first
@@ -62,4 +62,6 @@ int main()
         atomic_flag_clear_explicit(&f, std::memory_order_seq_cst);
         assert(f.test_and_set() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.flag/atomic_flag_test_and_set.pass.cpp b/libcxx/test/std/atomics/atomics.flag/atomic_flag_test_and_set.pass.cpp
index 009c859ffe482fb8a4a4b67de104f699a203a726..d73dc316d96e21c0ad0ca7ab68224d1344242629 100644
--- a/libcxx/test/std/atomics/atomics.flag/atomic_flag_test_and_set.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.flag/atomic_flag_test_and_set.pass.cpp
@@ -18,7 +18,7 @@
 #include <atomic>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::atomic_flag f;
@@ -32,4 +32,6 @@ int main()
         assert(atomic_flag_test_and_set(&f) == 0);
         assert(f.test_and_set() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.flag/atomic_flag_test_and_set_explicit.pass.cpp b/libcxx/test/std/atomics/atomics.flag/atomic_flag_test_and_set_explicit.pass.cpp
index 3a40328be8421560d38d2ebbeddd0e8d39a74768..972a6e84b6ff0be594ba0c360481c9018c163f16 100644
--- a/libcxx/test/std/atomics/atomics.flag/atomic_flag_test_and_set_explicit.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.flag/atomic_flag_test_and_set_explicit.pass.cpp
@@ -18,7 +18,7 @@
 #include <atomic>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::atomic_flag f;
@@ -92,4 +92,6 @@ int main()
         assert(atomic_flag_test_and_set_explicit(&f, std::memory_order_seq_cst) == 0);
         assert(f.test_and_set() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.flag/clear.pass.cpp b/libcxx/test/std/atomics/atomics.flag/clear.pass.cpp
index cc877a477b1d31ccb710573ab6054334b31e24cc..33378e4bd87ff217a01062719a313276a45d73f9 100644
--- a/libcxx/test/std/atomics/atomics.flag/clear.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.flag/clear.pass.cpp
@@ -18,7 +18,7 @@
 #include <atomic>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::atomic_flag f; // uninitialized
@@ -76,4 +76,6 @@ int main()
         f.clear(std::memory_order_seq_cst);
         assert(f.test_and_set() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.flag/copy_assign.fail.cpp b/libcxx/test/std/atomics/atomics.flag/copy_assign.fail.cpp
index 9fa766cad2ceb8f4bda32d73dad395a4048f52c9..aa5a24b9e9031c20aded8aaace366f0cd32e941a 100644
--- a/libcxx/test/std/atomics/atomics.flag/copy_assign.fail.cpp
+++ b/libcxx/test/std/atomics/atomics.flag/copy_assign.fail.cpp
@@ -15,9 +15,11 @@
 #include <atomic>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::atomic_flag f0;
     std::atomic_flag f;
     f = f0;
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.flag/copy_ctor.fail.cpp b/libcxx/test/std/atomics/atomics.flag/copy_ctor.fail.cpp
index f167651c925582c5da4e512bba165914f16cf1ab..10deaf1256d9bad4756d870770d3ec34e754afcc 100644
--- a/libcxx/test/std/atomics/atomics.flag/copy_ctor.fail.cpp
+++ b/libcxx/test/std/atomics/atomics.flag/copy_ctor.fail.cpp
@@ -15,8 +15,10 @@
 #include <atomic>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::atomic_flag f0;
     std::atomic_flag f(f0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.flag/copy_volatile_assign.fail.cpp b/libcxx/test/std/atomics/atomics.flag/copy_volatile_assign.fail.cpp
index 128778ab92f6b873f8e224f7c85db6e9b742447e..a453fab28766cf3129e37bbf0319d0189ff5df32 100644
--- a/libcxx/test/std/atomics/atomics.flag/copy_volatile_assign.fail.cpp
+++ b/libcxx/test/std/atomics/atomics.flag/copy_volatile_assign.fail.cpp
@@ -15,9 +15,11 @@
 #include <atomic>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::atomic_flag f0;
     volatile std::atomic_flag f;
     f = f0;
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.flag/default.pass.cpp b/libcxx/test/std/atomics/atomics.flag/default.pass.cpp
index 515e8108c1b7aa46d63b2badded83060d463da56..6a0d907fde94f71768883e7dda11718392d1d5a7 100644
--- a/libcxx/test/std/atomics/atomics.flag/default.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.flag/default.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     std::atomic_flag f;
     f.clear();
@@ -32,4 +32,6 @@ int main()
         assert(!zero.test_and_set());
         zero.~A();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.flag/init.pass.cpp b/libcxx/test/std/atomics/atomics.flag/init.pass.cpp
index 8ca3bc9ccda7c55238be6802d4e1d32fdcd553c3..a45784d802b3bc9f875d7448890965ddb16d6578 100644
--- a/libcxx/test/std/atomics/atomics.flag/init.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.flag/init.pass.cpp
@@ -18,8 +18,10 @@
 #include <atomic>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::atomic_flag f = ATOMIC_FLAG_INIT;
     assert(f.test_and_set() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.flag/test_and_set.pass.cpp b/libcxx/test/std/atomics/atomics.flag/test_and_set.pass.cpp
index d567734d14605bd9aa0e9081cce315436c47d4c2..1a198c1be84f345382ae0ce7d832daa135d095e8 100644
--- a/libcxx/test/std/atomics/atomics.flag/test_and_set.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.flag/test_and_set.pass.cpp
@@ -18,7 +18,7 @@
 #include <atomic>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::atomic_flag f;
@@ -104,4 +104,6 @@ int main()
         assert(f.test_and_set(std::memory_order_seq_cst) == 0);
         assert(f.test_and_set(std::memory_order_seq_cst) == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.general/nothing_to_do.pass.cpp b/libcxx/test/std/atomics/atomics.general/nothing_to_do.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/std/atomics/atomics.general/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.general/nothing_to_do.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.general/replace_failure_order.pass.cpp b/libcxx/test/std/atomics/atomics.general/replace_failure_order.pass.cpp
index b246fc016fbb6cad80c020ce4a8c3d3a3b727f7b..ee23841382bfce87b0eaea999ce0cadeba5631e3 100644
--- a/libcxx/test/std/atomics/atomics.general/replace_failure_order.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.general/replace_failure_order.pass.cpp
@@ -23,7 +23,7 @@
 
 #include <atomic>
 
-int main() {
+int main(int, char**) {
     std::atomic<int> i;
     volatile std::atomic<int> v;
     int exp = 0;
diff --git a/libcxx/test/std/atomics/atomics.lockfree/isalwayslockfree.pass.cpp b/libcxx/test/std/atomics/atomics.lockfree/isalwayslockfree.pass.cpp
index 5d1f3ba9a7ce1b2de9cf3a669c76f9f03fda2a48..d2ce1cefd28595e50b9a94c91a424aece47a29a7 100644
--- a/libcxx/test/std/atomics/atomics.lockfree/isalwayslockfree.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.lockfree/isalwayslockfree.pass.cpp
@@ -134,4 +134,4 @@ void run()
     static_assert(std::atomic<std::nullptr_t>::is_always_lock_free == (2 == ATOMIC_POINTER_LOCK_FREE));
 }
 
-int main() { run(); }
+int main(int, char**) { run(); return 0; }
diff --git a/libcxx/test/std/atomics/atomics.lockfree/lockfree.pass.cpp b/libcxx/test/std/atomics/atomics.lockfree/lockfree.pass.cpp
index cc448e662881adc4cc57c1ba1959dbdf7ea8eb4f..b86893e0b9cb5f7864dc1cd4856bc41f3c1a1f4c 100644
--- a/libcxx/test/std/atomics/atomics.lockfree/lockfree.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.lockfree/lockfree.pass.cpp
@@ -24,7 +24,7 @@
 #include <atomic>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert(ATOMIC_BOOL_LOCK_FREE == 0 ||
            ATOMIC_BOOL_LOCK_FREE == 1 ||
@@ -56,4 +56,6 @@ int main()
     assert(ATOMIC_POINTER_LOCK_FREE == 0 ||
            ATOMIC_POINTER_LOCK_FREE == 1 ||
            ATOMIC_POINTER_LOCK_FREE == 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.order/kill_dependency.pass.cpp b/libcxx/test/std/atomics/atomics.order/kill_dependency.pass.cpp
index 144bf5059074733b921a1aa2f7ebd790e6fd5a29..998b0cef38b25558ae7848aed908de528b166451 100644
--- a/libcxx/test/std/atomics/atomics.order/kill_dependency.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.order/kill_dependency.pass.cpp
@@ -15,8 +15,10 @@
 #include <atomic>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert(std::kill_dependency(5) == 5);
     assert(std::kill_dependency(-5.5) == -5.5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.order/memory_order.pass.cpp b/libcxx/test/std/atomics/atomics.order/memory_order.pass.cpp
index 69a46eac3d1e33db7e828dfbf092b29d88657d13..973f58583cab01997ebfc932cc4bc32e7dc8eedd 100644
--- a/libcxx/test/std/atomics/atomics.order/memory_order.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.order/memory_order.pass.cpp
@@ -19,7 +19,7 @@
 #include <atomic>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert(std::memory_order_relaxed == 0);
     assert(std::memory_order_consume == 1);
@@ -29,4 +29,6 @@ int main()
     assert(std::memory_order_seq_cst == 5);
     std::memory_order o = std::memory_order_seq_cst;
     assert(o == 5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.syn/nothing_to_do.pass.cpp b/libcxx/test/std/atomics/atomics.syn/nothing_to_do.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/std/atomics/atomics.syn/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.syn/nothing_to_do.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.generic/address.pass.cpp b/libcxx/test/std/atomics/atomics.types.generic/address.pass.cpp
index 98c8d4f24a24e76c17a4d13ff711f1ac2f6548ed..598889736ab91008a7f4c279c19efd09911f8509 100644
--- a/libcxx/test/std/atomics/atomics.types.generic/address.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.generic/address.pass.cpp
@@ -136,7 +136,9 @@ void test()
     do_test<volatile A, T>();
 }
 
-int main()
+int main(int, char**)
 {
     test<std::atomic<int*>, int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.generic/bool.pass.cpp b/libcxx/test/std/atomics/atomics.types.generic/bool.pass.cpp
index 33901ce9b318c89d8f319bbd85176cda52b465c2..154d0bfe67d56c1d901df044d7433bb004f18259 100644
--- a/libcxx/test/std/atomics/atomics.types.generic/bool.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.generic/bool.pass.cpp
@@ -58,7 +58,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         volatile std::atomic<bool> obj(true);
@@ -232,4 +232,6 @@ int main()
         assert(zero == false);
         zero.~A();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.generic/cstdint_typedefs.pass.cpp b/libcxx/test/std/atomics/atomics.types.generic/cstdint_typedefs.pass.cpp
index 0c76e7b0fd6435bb61cd532ddd49c63df5974043..a0648ff9c0a18481718385e93da08e17f522a984 100644
--- a/libcxx/test/std/atomics/atomics.types.generic/cstdint_typedefs.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.generic/cstdint_typedefs.pass.cpp
@@ -39,7 +39,7 @@
 #include <type_traits>
 #include <cstdint>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::atomic<  std::int_least8_t>,   std::atomic_int_least8_t>::value), "");
     static_assert((std::is_same<std::atomic< std::uint_least8_t>,  std::atomic_uint_least8_t>::value), "");
@@ -65,4 +65,6 @@ int main()
     static_assert((std::is_same<std::atomic<std::ptrdiff_t>, std::atomic_ptrdiff_t>::value), "");
     static_assert((std::is_same<std::atomic< std::intmax_t>,  std::atomic_intmax_t>::value), "");
     static_assert((std::is_same<std::atomic<std::uintmax_t>, std::atomic_uintmax_t>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.generic/integral.pass.cpp b/libcxx/test/std/atomics/atomics.types.generic/integral.pass.cpp
index e59bee43c55d5efcb59545e34a519ac80ed5aff4..62ef06bcc16ebbad4a2460c4c1afda2716f0d33a 100644
--- a/libcxx/test/std/atomics/atomics.types.generic/integral.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.generic/integral.pass.cpp
@@ -167,7 +167,7 @@ void test()
 }
 
 
-int main()
+int main(int, char**)
 {
     test<std::atomic_char, char>();
     test<std::atomic_schar, signed char>();
@@ -220,4 +220,6 @@ int main()
     test<volatile std::atomic_uint32_t, uint32_t>();
     test<volatile std::atomic_int64_t,   int64_t>();
     test<volatile std::atomic_uint64_t, uint64_t>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.generic/integral_typedefs.pass.cpp b/libcxx/test/std/atomics/atomics.types.generic/integral_typedefs.pass.cpp
index d63043b847321965145b470627dc9bf2a99bcb5e..faa682b8cef2504e7b10da4bf6d64f2c80717f71 100644
--- a/libcxx/test/std/atomics/atomics.types.generic/integral_typedefs.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.generic/integral_typedefs.pass.cpp
@@ -40,7 +40,7 @@
 #include <atomic>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::atomic<char>, std::atomic_char>::value), "");
     static_assert((std::is_same<std::atomic<signed char>, std::atomic_schar>::value), "");
@@ -71,4 +71,6 @@ int main()
     static_assert((std::is_same<std::atomic<uint32_t>,  std::atomic_uint32_t>::value), "");
     static_assert((std::is_same<std::atomic<int64_t>,   std::atomic_int64_t>::value), "");
     static_assert((std::is_same<std::atomic<uint64_t>,  std::atomic_uint64_t>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.generic/trivially_copyable.fail.cpp b/libcxx/test/std/atomics/atomics.types.generic/trivially_copyable.fail.cpp
index 6ea65495c434243d44059af00d05969064b146fa..3ec8ed25c97659982bc108a2b494735a27e71281 100644
--- a/libcxx/test/std/atomics/atomics.types.generic/trivially_copyable.fail.cpp
+++ b/libcxx/test/std/atomics/atomics.types.generic/trivially_copyable.fail.cpp
@@ -63,7 +63,9 @@ void test ( T t ) {
     std::atomic<T> t0(t);
 }
 
-int main()
+int main(int, char**)
 {
     test(NotTriviallyCopyable(42));
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.generic/trivially_copyable.pass.cpp b/libcxx/test/std/atomics/atomics.types.generic/trivially_copyable.pass.cpp
index 03c68de8658eb7aefac49bd272b5dc0efe9c45c7..229761eb32685f18956be17b994b24d18ba11215 100644
--- a/libcxx/test/std/atomics/atomics.types.generic/trivially_copyable.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.generic/trivially_copyable.pass.cpp
@@ -68,9 +68,11 @@ void test ( T t ) {
     std::atomic<T> t0(t);
     }
 
-int main()
+int main(int, char**)
 {
     test(TriviallyCopyable(42));
     test(std::this_thread::get_id());
     test(std::chrono::nanoseconds(2));
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.arith/nothing_to_do.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.arith/nothing_to_do.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.arith/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.arith/nothing_to_do.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.general/nothing_to_do.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.general/nothing_to_do.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.general/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.general/nothing_to_do.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.pointer/nothing_to_do.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.pointer/nothing_to_do.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.pointer/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.pointer/nothing_to_do.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_strong.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_strong.pass.cpp
index 8d96adeea74d8b1df9fcc64b3f26052691d23670..041845d5be2a27bf0ee69fe4c19f29a9d4dfcb31 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_strong.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_strong.pass.cpp
@@ -55,7 +55,9 @@ struct TestFn {
   }
 };
 
-int main()
+int main(int, char**)
 {
     TestEachAtomicType<TestFn>()();
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_strong_explicit.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_strong_explicit.pass.cpp
index b557817d6908d4f2391a59a16fa3649b956c3624..99a85088633685d01707795d0ef5ae3119186f92 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_strong_explicit.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_strong_explicit.pass.cpp
@@ -62,7 +62,9 @@ struct TestFn {
   }
 };
 
-int main()
+int main(int, char**)
 {
     TestEachAtomicType<TestFn>()();
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_weak.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_weak.pass.cpp
index 53f4174ec86ca200f5f8fe25c198246420b0db4a..a2a9e205db8ecf895e053e61ea1dac92fbcd616e 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_weak.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_weak.pass.cpp
@@ -56,7 +56,9 @@ struct TestFn {
   }
 };
 
-int main()
+int main(int, char**)
 {
     TestEachAtomicType<TestFn>()();
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_weak_explicit.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_weak_explicit.pass.cpp
index 7edfb91cdc69b8cc3b2a7aa807cf9b2f769a8be8..2ad17f1cbe6e70de446019d4fc61c36d2385edfa 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_weak_explicit.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_compare_exchange_weak_explicit.pass.cpp
@@ -64,7 +64,9 @@ struct TestFn {
   }
 };
 
-int main()
+int main(int, char**)
 {
     TestEachAtomicType<TestFn>()();
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_exchange.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_exchange.pass.cpp
index 43e6b804ba2e93e4eb12c719cf26aaf88ea699f8..d13238e652839f095b5d7fd35ed4299955908196 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_exchange.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_exchange.pass.cpp
@@ -41,7 +41,9 @@ struct TestFn {
 };
 
 
-int main()
+int main(int, char**)
 {
     TestEachAtomicType<TestFn>()();
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_exchange_explicit.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_exchange_explicit.pass.cpp
index 14e8ed1af60a0141cd3ab3cc912a7081d38b6b31..2acbcb20f7ce8483485d6918602c89abc1294c53 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_exchange_explicit.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_exchange_explicit.pass.cpp
@@ -43,7 +43,9 @@ struct TestFn {
 };
 
 
-int main()
+int main(int, char**)
 {
     TestEachAtomicType<TestFn>()();
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_add.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_add.pass.cpp
index deb68b170e4e1f32d83fcb7594fc2ac2a7448dff..f84a489834867fc99d4251e1d227dce0c8689284 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_add.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_add.pass.cpp
@@ -74,9 +74,11 @@ void testp()
     }
 }
 
-int main()
+int main(int, char**)
 {
     TestEachIntegralType<TestFn>()();
     testp<int*>();
     testp<const int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_add_explicit.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_add_explicit.pass.cpp
index a75acb34118d01054eb4320f42fabd32df1df168..fbdf3fffcd73ecbf2b15251da1d4586aa547c296 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_add_explicit.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_add_explicit.pass.cpp
@@ -79,9 +79,11 @@ testp()
     }
 }
 
-int main()
+int main(int, char**)
 {
     TestEachIntegralType<TestFn>()();
     testp<int*>();
     testp<const int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_and.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_and.pass.cpp
index f80d7a82c5d8c640f28da2047c4701085431d8fc..dfaaaa3e5b4619ddba4fbfbe63d26273f08dca85 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_and.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_and.pass.cpp
@@ -44,7 +44,9 @@ struct TestFn {
   }
 };
 
-int main()
+int main(int, char**)
 {
     TestEachIntegralType<TestFn>()();
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_and_explicit.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_and_explicit.pass.cpp
index 77a89dc79e7b37cee74731da0b38923bef5675bc..d31245a84217cec9bde84515d966275af603ac31 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_and_explicit.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_and_explicit.pass.cpp
@@ -46,7 +46,9 @@ struct TestFn {
   }
 };
 
-int main()
+int main(int, char**)
 {
     TestEachIntegralType<TestFn>()();
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_or.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_or.pass.cpp
index 19c321539e3f13199ac60f4b63b14bbcf2d79d9d..741dca00e86c763bcc0c3eae170047d3c03eeb08 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_or.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_or.pass.cpp
@@ -44,7 +44,9 @@ struct TestFn {
   }
 };
 
-int main()
+int main(int, char**)
 {
     TestEachIntegralType<TestFn>()();
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_or_explicit.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_or_explicit.pass.cpp
index af0a7e8ab8c0caded49fc54549eee002205adab1..e56e946f43cb13a3e22fd14d8b606bffe920b3a9 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_or_explicit.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_or_explicit.pass.cpp
@@ -46,7 +46,9 @@ struct TestFn {
   }
 };
 
-int main()
+int main(int, char**)
 {
     TestEachIntegralType<TestFn>()();
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_sub.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_sub.pass.cpp
index 8298327a994bbcf2acacb56fa3059f506ad461ad..13fde4ad6a75c41ec22cecbe71dade0f65f08c77 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_sub.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_sub.pass.cpp
@@ -74,9 +74,11 @@ void testp()
     }
 }
 
-int main()
+int main(int, char**)
 {
     TestEachIntegralType<TestFn>()();
     testp<int*>();
     testp<const int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_sub_explicit.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_sub_explicit.pass.cpp
index b7447ad7a7211a09ecf333344e528cef2a40dfb9..af97bcc60221e51e408c33fe0f9d181c78011589 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_sub_explicit.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_sub_explicit.pass.cpp
@@ -79,9 +79,11 @@ void testp()
     }
 }
 
-int main()
+int main(int, char**)
 {
     TestEachIntegralType<TestFn>()();
     testp<int*>();
     testp<const int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_xor.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_xor.pass.cpp
index 5eaf5039faa295ce5f972e44292b66136122fcc6..0e6f99f36291af8a28997314f6aac45124713065 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_xor.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_xor.pass.cpp
@@ -44,7 +44,9 @@ struct TestFn {
   }
 };
 
-int main()
+int main(int, char**)
 {
     TestEachIntegralType<TestFn>()();
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_xor_explicit.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_xor_explicit.pass.cpp
index 83ac8dbe52f9f864c98d8315a360b788ecdffc1b..ece15694561e49a86c345ef9cce3d56b29be3480 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_xor_explicit.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_fetch_xor_explicit.pass.cpp
@@ -46,7 +46,9 @@ struct TestFn {
   }
 };
 
-int main()
+int main(int, char**)
 {
     TestEachIntegralType<TestFn>()();
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_init.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_init.pass.cpp
index bcb729469fbabf5d66f8a6e7f950a5a9408e3d93..0e5b920f91e8b437c9265a40b14c4d3f69b5ddbd 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_init.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_init.pass.cpp
@@ -38,7 +38,9 @@ struct TestFn {
   }
 };
 
-int main()
+int main(int, char**)
 {
     TestEachAtomicType<TestFn>()();
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_is_lock_free.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_is_lock_free.pass.cpp
index e8352cd8e3cd0503417c62986492523a2d1bc18b..bfa24dae56244fa96502bd5dbf8df06e91754c0f 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_is_lock_free.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_is_lock_free.pass.cpp
@@ -40,8 +40,10 @@ struct A
     char _[4];
 };
 
-int main()
+int main(int, char**)
 {
     TestFn<A>()();
     TestEachAtomicType<TestFn>()();
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_load.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_load.pass.cpp
index 9431331d676bf96aba28cbb83c69a805d8854ba4..b775c54673726c4f2f274feab63837f9a5936499 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_load.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_load.pass.cpp
@@ -38,7 +38,9 @@ struct TestFn {
   }
 };
 
-int main()
+int main(int, char**)
 {
     TestEachAtomicType<TestFn>()();
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_load_explicit.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_load_explicit.pass.cpp
index d6cf08605027cd92198f705d18cde500cbec1c8e..0384baa5a7f4bcf424381ad118ff634d1c4268f9 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_load_explicit.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_load_explicit.pass.cpp
@@ -38,7 +38,9 @@ struct TestFn {
   }
 };
 
-int main()
+int main(int, char**)
 {
     TestEachAtomicType<TestFn>()();
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_store.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_store.pass.cpp
index 6f91792fba61ca7e1fdd763702040cecc484b11d..0fb3bc7dda9367902c3b9988ca286f642be5a5a4 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_store.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_store.pass.cpp
@@ -38,7 +38,9 @@ struct TestFn {
 };
 
 
-int main()
+int main(int, char**)
 {
     TestEachAtomicType<TestFn>()();
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_store_explicit.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_store_explicit.pass.cpp
index c63c5cc1bbb9e225cf9abd91abf949db8c992e88..11aa295dee4b2783b6bc5768e37ea8cb4528d575 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_store_explicit.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_store_explicit.pass.cpp
@@ -38,7 +38,9 @@ struct TestFn {
 };
 
 
-int main()
+int main(int, char**)
 {
     TestEachAtomicType<TestFn>()();
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_var_init.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_var_init.pass.cpp
index 9111d8bd0371b2c502523aa7bb0e05029059e6c9..1588af3273fb6d00993ab81539fa2ac372da334e 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_var_init.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_var_init.pass.cpp
@@ -17,8 +17,10 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::atomic<int> v = ATOMIC_VAR_INIT(5);
     assert(v == 5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/ctor.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/ctor.pass.cpp
index 563a053373e0d41829b8840ce79e039f59c8704e..d692e931b49a4bdd3c213e954e7f0d171fdd79bc 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/ctor.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.req/ctor.pass.cpp
@@ -56,8 +56,10 @@ struct TestFunc {
 };
 
 
-int main()
+int main(int, char**)
 {
     TestFunc<UserType>()();
     TestEachIntegralType<TestFunc>()();
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.templ/nothing_to_do.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.templ/nothing_to_do.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.templ/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/atomics.types.operations.templ/nothing_to_do.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/atomics/atomics.types.operations/nothing_to_do.pass.cpp b/libcxx/test/std/atomics/atomics.types.operations/nothing_to_do.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/std/atomics/atomics.types.operations/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.operations/nothing_to_do.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/iterator_types.pass.cpp b/libcxx/test/std/containers/associative/iterator_types.pass.cpp
index f18fa2b4fc4f61f0ae7f9d159c0f0af5c20b2d0e..1b8556fb558aa8dae4f00bc275d0e97471935e06 100644
--- a/libcxx/test/std/containers/associative/iterator_types.pass.cpp
+++ b/libcxx/test/std/containers/associative/iterator_types.pass.cpp
@@ -50,7 +50,7 @@ void testSet() {
   }
 }
 
-int main() {
+int main(int, char**) {
   {
     typedef std::map<int, int> Map;
     typedef std::pair<const int, int> ValueTp;
@@ -127,4 +127,6 @@ int main() {
     testSet<Set, ValueTp, min_pointer<const ValueTp>>();
   }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/PR28469_undefined_behavior_segfault.sh.cpp b/libcxx/test/std/containers/associative/map/PR28469_undefined_behavior_segfault.sh.cpp
index ff0be20842d03a51ec0d8b2387d042109f1c9bde..030fdaf39184a91889210eca652abd181ca6bf9c 100644
--- a/libcxx/test/std/containers/associative/map/PR28469_undefined_behavior_segfault.sh.cpp
+++ b/libcxx/test/std/containers/associative/map/PR28469_undefined_behavior_segfault.sh.cpp
@@ -24,7 +24,9 @@ struct F {
     F() { m[42] = &dummy; }
 };
 
-int main() {
+int main(int, char**) {
     F f;
     f = F();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/allocator_mismatch.fail.cpp b/libcxx/test/std/containers/associative/map/allocator_mismatch.fail.cpp
index 08f5ee94fb03a41b30efe3f79ddacd1401251fc9..faec5aa401e135fb2ffdaa9bcf98705afc881ce5 100644
--- a/libcxx/test/std/containers/associative/map/allocator_mismatch.fail.cpp
+++ b/libcxx/test/std/containers/associative/map/allocator_mismatch.fail.cpp
@@ -11,7 +11,9 @@
 
 #include <map>
 
-int main()
+int main(int, char**)
 {
     std::map<int, int, std::less<int>, std::allocator<long> > m;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/compare.pass.cpp b/libcxx/test/std/containers/associative/map/compare.pass.cpp
index fedc9d2b3a18ae5d70f7b25beabbafed02148993..84de271842be62a2015991ff464dbb77cde4130b 100644
--- a/libcxx/test/std/containers/associative/map/compare.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/compare.pass.cpp
@@ -24,7 +24,7 @@ struct Key {
   bool operator< (const Key&) const { return false; }
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::map<Key, int> MapT;
     typedef MapT::iterator Iter;
@@ -48,4 +48,6 @@ int main()
         assert(!result2.second);
         assert(map[Key(0)] == 42);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/gcc_workaround.pass.cpp b/libcxx/test/std/containers/associative/map/gcc_workaround.pass.cpp
index 622449facc118c795118463c42a39af5f1154572..9e05b66a5ebaca4fd46e49aa0931c2c94e9431b9 100644
--- a/libcxx/test/std/containers/associative/map/gcc_workaround.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/gcc_workaround.pass.cpp
@@ -15,7 +15,4 @@ std::map<int,int>::iterator it;
 using std::set;
 using std::multiset;
 
-int main(void)
-{
-       return 0;
-}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/containers/associative/map/incomplete_type.pass.cpp b/libcxx/test/std/containers/associative/map/incomplete_type.pass.cpp
index 1bc320e9cbff314e2bb84173ebfc9fd0d087f8b1..a45c50c32940f0a73d244c0c15b67cfbb1e6c662 100644
--- a/libcxx/test/std/containers/associative/map/incomplete_type.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/incomplete_type.pass.cpp
@@ -23,6 +23,8 @@ struct A {
 
 inline bool operator==(A const& L, A const& R) { return &L == &R; }
 inline bool operator<(A const& L, A const& R)  { return L.data < R.data; }
-int main() {
+int main(int, char**) {
     A a;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.access/at.pass.cpp b/libcxx/test/std/containers/associative/map/map.access/at.pass.cpp
index 475dd641cc2c5fe4c307fc6d708a04a38092b033..c13c6a64acb20b3ccd1fc260ff9eefe414863587 100644
--- a/libcxx/test/std/containers/associative/map/map.access/at.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.access/at.pass.cpp
@@ -20,7 +20,7 @@
 #include "min_allocator.h"
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<const int, double> V;
@@ -160,4 +160,6 @@ int main()
         assert(m.size() == 7);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.access/empty.fail.cpp b/libcxx/test/std/containers/associative/map/map.access/empty.fail.cpp
index 0305fdb5684f64036c2f637079dc5fef7ce1ab1a..61c4e757b0c3668d3139cb6dc32a12b72b333578 100644
--- a/libcxx/test/std/containers/associative/map/map.access/empty.fail.cpp
+++ b/libcxx/test/std/containers/associative/map/map.access/empty.fail.cpp
@@ -20,8 +20,10 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     std::map<int, int> c;
     c.empty();  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.access/empty.pass.cpp b/libcxx/test/std/containers/associative/map/map.access/empty.pass.cpp
index 1317ee31048d01822831db454b5ee6f253b317e6..cff13df7af2888e4994b188009de231924cc7fa1 100644
--- a/libcxx/test/std/containers/associative/map/map.access/empty.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.access/empty.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::map<int, double> M;
@@ -39,4 +39,6 @@ int main()
     assert(m.empty());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.access/index_key.pass.cpp b/libcxx/test/std/containers/associative/map/map.access/index_key.pass.cpp
index 1d842205a8fdb7a913ca839c5b1757b215c43696..8df052e01627b65dbe0641d74da0625510acf909 100644
--- a/libcxx/test/std/containers/associative/map/map.access/index_key.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.access/index_key.pass.cpp
@@ -23,7 +23,7 @@
 #include "container_test_types.h"
 #endif
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<const int, double> V;
@@ -139,4 +139,6 @@ int main()
     assert(m.size() == 8);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.access/index_rv_key.pass.cpp b/libcxx/test/std/containers/associative/map/map.access/index_rv_key.pass.cpp
index 523d4e6d8822e869fd82809ec9493a2ea9120e09..7effa0c64151e0e30f63018f311d34680c476a4c 100644
--- a/libcxx/test/std/containers/associative/map/map.access/index_rv_key.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.access/index_rv_key.pass.cpp
@@ -23,7 +23,7 @@
 #include "min_allocator.h"
 #include "container_test_types.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::map<MoveOnly, double> m;
@@ -76,4 +76,6 @@ int main()
             }
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.access/index_tuple.pass.cpp b/libcxx/test/std/containers/associative/map/map.access/index_tuple.pass.cpp
index 5f39bece03b5e243d73d209cbf654fa8b76d231c..bc99f6ef8e3c3fa68d0f453d30e2fb792ddd2639 100644
--- a/libcxx/test/std/containers/associative/map/map.access/index_tuple.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.access/index_tuple.pass.cpp
@@ -22,9 +22,11 @@
 #include <tuple>
 
 
-int main()
+int main(int, char**)
 {
     using namespace std;
     map<tuple<int,int>, size_t> m;
     m[make_tuple(2,3)]=7;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.access/iterator.pass.cpp b/libcxx/test/std/containers/associative/map/map.access/iterator.pass.cpp
index c1c503733f25db8edbb7c24be3e04aa1f611448b..39b573a1392e0d60ad5f58ff900115fb7399b22c 100644
--- a/libcxx/test/std/containers/associative/map/map.access/iterator.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.access/iterator.pass.cpp
@@ -32,7 +32,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<const int, double> V;
@@ -225,4 +225,6 @@ int main()
         assert (!(cii != ii1 ));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.access/max_size.pass.cpp b/libcxx/test/std/containers/associative/map/map.access/max_size.pass.cpp
index 1bb873f4b5d841db61fba4f1a0f350e065e5eee2..b38cf1146389797a98f5ab901b64623b89275175 100644
--- a/libcxx/test/std/containers/associative/map/map.access/max_size.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.access/max_size.pass.cpp
@@ -20,7 +20,7 @@
 #include "test_allocator.h"
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
   typedef std::pair<const int, int> KV;
   {
@@ -47,4 +47,6 @@ int main()
     assert(c.max_size() <= max_dist);
     assert(c.max_size() <= alloc_max_size(c.get_allocator()));
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.access/size.pass.cpp b/libcxx/test/std/containers/associative/map/map.access/size.pass.cpp
index 4408dc54e64422bbb24001d4a305f8ef59372638..bb4b14e026fb166019c0e40e10f4c94ba5c32516 100644
--- a/libcxx/test/std/containers/associative/map/map.access/size.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.access/size.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::map<int, double> M;
@@ -55,4 +55,6 @@ int main()
     assert(m.size() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.cons/alloc.pass.cpp b/libcxx/test/std/containers/associative/map/map.cons/alloc.pass.cpp
index 04000bec93efd641985e068188ac48620e4ae5ef..5bb9abc88f7d3415d269dadf78d0183e00706cb6 100644
--- a/libcxx/test/std/containers/associative/map/map.cons/alloc.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.cons/alloc.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::less<int> C;
@@ -46,4 +46,6 @@ int main()
     assert(m.get_allocator() == A());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.cons/assign_initializer_list.pass.cpp b/libcxx/test/std/containers/associative/map/map.cons/assign_initializer_list.pass.cpp
index 664d6cf083ec646aa60b8c67c12f64c48c7a9717..612838ef6670ad17d383dbc82fd5f0d41dc2072a 100644
--- a/libcxx/test/std/containers/associative/map/map.cons/assign_initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.cons/assign_initializer_list.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<const int, double> V;
@@ -69,4 +69,6 @@ int main()
     assert(*next(m.begin()) == V(2, 1));
     assert(*next(m.begin(), 2) == V(3, 1));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.cons/compare.pass.cpp b/libcxx/test/std/containers/associative/map/map.cons/compare.pass.cpp
index 2fb00ebde7c7b26e385cecc967870235e915a4c3..40a8e38aef2f5326bfbfa277c28afec794657c28 100644
--- a/libcxx/test/std/containers/associative/map/map.cons/compare.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.cons/compare.pass.cpp
@@ -20,7 +20,7 @@
 #include "../../../test_compare.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef test_compare<std::less<int> > C;
@@ -38,4 +38,6 @@ int main()
     assert(m.key_comp() == C(3));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.cons/compare_alloc.pass.cpp b/libcxx/test/std/containers/associative/map/map.cons/compare_alloc.pass.cpp
index d4de57163d9989b535efba19943ee703df262037..71bc32295e0621472acbbec1d4e708ceaba0ac77 100644
--- a/libcxx/test/std/containers/associative/map/map.cons/compare_alloc.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.cons/compare_alloc.pass.cpp
@@ -19,7 +19,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef test_compare<std::less<int> > C;
@@ -50,4 +50,6 @@ int main()
     assert(m.get_allocator() == A{});
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.cons/compare_copy_constructible.fail.cpp b/libcxx/test/std/containers/associative/map/map.cons/compare_copy_constructible.fail.cpp
index 1e75326dee2db37a5df21624805579c68e72ab7c..3c714de40af934b55919ef04a81dd11b21563ed1 100644
--- a/libcxx/test/std/containers/associative/map/map.cons/compare_copy_constructible.fail.cpp
+++ b/libcxx/test/std/containers/associative/map/map.cons/compare_copy_constructible.fail.cpp
@@ -23,6 +23,8 @@ private:
     };
 
 
-int main() {
+int main(int, char**) {
     std::map<int, int, Comp<int> > m;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.cons/copy.pass.cpp b/libcxx/test/std/containers/associative/map/map.cons/copy.pass.cpp
index 0e7266d59db23c528329887f7fae3ebce875361b..8eec27b3eabed962801a916f488954106521fe51 100644
--- a/libcxx/test/std/containers/associative/map/map.cons/copy.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.cons/copy.pass.cpp
@@ -20,7 +20,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<const int, double> V;
@@ -126,4 +126,6 @@ int main()
         assert(*next(mo.begin(), 2) == V(3, 1));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.cons/copy_alloc.pass.cpp b/libcxx/test/std/containers/associative/map/map.cons/copy_alloc.pass.cpp
index 0e01b3674dfcb5e937ed5fcaf1d19b8d9fb8e611..d25504382e4ef201ffda1179c54bedd1f9595be1 100644
--- a/libcxx/test/std/containers/associative/map/map.cons/copy_alloc.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.cons/copy_alloc.pass.cpp
@@ -19,7 +19,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<const int, double> V;
@@ -125,4 +125,6 @@ int main()
     assert(*next(mo.begin(), 2) == V(3, 1));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.cons/copy_assign.pass.cpp b/libcxx/test/std/containers/associative/map/map.cons/copy_assign.pass.cpp
index e63cbe951fa75a7d6595ea82145e53ba75402836..a902e05603be97dd8e9e40027457b9af5f70ecfb 100644
--- a/libcxx/test/std/containers/associative/map/map.cons/copy_assign.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.cons/copy_assign.pass.cpp
@@ -108,7 +108,7 @@ bool balanced_allocs() {
     }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<const int, double> V;
@@ -337,4 +337,6 @@ int main()
     }
     assert(balanced_allocs());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.cons/default.pass.cpp b/libcxx/test/std/containers/associative/map/map.cons/default.pass.cpp
index 3a2b7fb4837cc666fc675eab6117c1cc8b5c657c..5d3fcaee117adc13caceebe0837622804533137e 100644
--- a/libcxx/test/std/containers/associative/map/map.cons/default.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.cons/default.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::map<int, double> m;
@@ -50,4 +50,6 @@ int main()
     assert(m.begin() == m.end());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.cons/default_noexcept.pass.cpp b/libcxx/test/std/containers/associative/map/map.cons/default_noexcept.pass.cpp
index 61f87b3c1c26ea0a25474b8614cc300fb12b781c..2e4b4242d2d3d6782a486a915cb5077c44fa1bf3 100644
--- a/libcxx/test/std/containers/associative/map/map.cons/default_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.cons/default_noexcept.pass.cpp
@@ -33,7 +33,7 @@ struct some_comp
     bool operator()(const T&, const T&) const { return false; }
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::pair<const MoveOnly, MoveOnly> V;
 #if defined(_LIBCPP_VERSION)
@@ -54,4 +54,6 @@ int main()
         typedef std::map<MoveOnly, MoveOnly, some_comp<MoveOnly>> C;
         static_assert(!std::is_nothrow_default_constructible<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.cons/default_recursive.pass.cpp b/libcxx/test/std/containers/associative/map/map.cons/default_recursive.pass.cpp
index fb01aacf639427cdd90f72ec7ffe66536277690f..af8fbe79f0bdd0c8759f4f0a14cd7e13035da609 100644
--- a/libcxx/test/std/containers/associative/map/map.cons/default_recursive.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.cons/default_recursive.pass.cpp
@@ -23,6 +23,8 @@ struct X
     std::map<int, X>::const_reverse_iterator cri;
 };
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.cons/dtor_noexcept.pass.cpp b/libcxx/test/std/containers/associative/map/map.cons/dtor_noexcept.pass.cpp
index fb07754c6acdd5fcf3abbac28f729860104f7544..2a2e89bf4405c90588c35fd616e5eb6a56ba6df3 100644
--- a/libcxx/test/std/containers/associative/map/map.cons/dtor_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.cons/dtor_noexcept.pass.cpp
@@ -27,7 +27,7 @@ struct some_comp
     bool operator()(const T&, const T&) const noexcept { return false; }
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::pair<const MoveOnly, MoveOnly> V;
     {
@@ -48,4 +48,6 @@ int main()
         static_assert(!std::is_nothrow_destructible<C>::value, "");
     }
 #endif // _LIBCPP_VERSION
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.cons/initializer_list.pass.cpp b/libcxx/test/std/containers/associative/map/map.cons/initializer_list.pass.cpp
index b7f916c11194241988ec349d043753553aec5854..1303f7ef2bad42e4a1df5bcfc0223cb8d6cdbb2f 100644
--- a/libcxx/test/std/containers/associative/map/map.cons/initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.cons/initializer_list.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<const int, double> V;
@@ -61,4 +61,6 @@ int main()
     assert(*next(m.begin()) == V(2, 1));
     assert(*next(m.begin(), 2) == V(3, 1));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.cons/initializer_list_compare.pass.cpp b/libcxx/test/std/containers/associative/map/map.cons/initializer_list_compare.pass.cpp
index 887597768bc72a66e2e35482ff9c1f836315989d..9b6a47ac334ca5eb85621ac060164729dcd1ec18 100644
--- a/libcxx/test/std/containers/associative/map/map.cons/initializer_list_compare.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.cons/initializer_list_compare.pass.cpp
@@ -19,7 +19,7 @@
 #include "../../../test_compare.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<const int, double> V;
@@ -63,4 +63,6 @@ int main()
     assert(*next(m.begin(), 2) == V(3, 1));
     assert(m.key_comp() == C(3));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.cons/initializer_list_compare_alloc.pass.cpp b/libcxx/test/std/containers/associative/map/map.cons/initializer_list_compare_alloc.pass.cpp
index 5288d64f01d66b0072c270f6cdd093313d928df9..0da3115f76f7c12f25ce272feb4521cf8be63b79 100644
--- a/libcxx/test/std/containers/associative/map/map.cons/initializer_list_compare_alloc.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.cons/initializer_list_compare_alloc.pass.cpp
@@ -20,7 +20,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<const int, double> V;
@@ -116,4 +116,6 @@ int main()
     assert(m.key_comp() == C(3));
     assert(m.get_allocator() == a);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.cons/iter_iter.pass.cpp b/libcxx/test/std/containers/associative/map/map.cons/iter_iter.pass.cpp
index 2a17bffb50a03b0081ed3bf3083bd4ab28b50a6d..243800cfd9ba9d2b466b1a4e002d1726bd6ae3f8 100644
--- a/libcxx/test/std/containers/associative/map/map.cons/iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.cons/iter_iter.pass.cpp
@@ -18,7 +18,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<const int, double> V;
@@ -64,4 +64,6 @@ int main()
     assert(*next(m.begin(), 2) == V(3, 1));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.cons/iter_iter_comp.pass.cpp b/libcxx/test/std/containers/associative/map/map.cons/iter_iter_comp.pass.cpp
index 41672578333eef62dbd9718b9d90d2e679be8dd0..12a079ea01c72f6238f38c6072e452d0f6c9478b 100644
--- a/libcxx/test/std/containers/associative/map/map.cons/iter_iter_comp.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.cons/iter_iter_comp.pass.cpp
@@ -19,7 +19,7 @@
 #include "../../../test_compare.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<const int, double> V;
@@ -69,4 +69,6 @@ int main()
     assert(*next(m.begin(), 2) == V(3, 1));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.cons/iter_iter_comp_alloc.pass.cpp b/libcxx/test/std/containers/associative/map/map.cons/iter_iter_comp_alloc.pass.cpp
index c8861573a77a6532a56dffd6e0166bce04efaa92..56396799dc9b30f1d01a1c9ca988b1fa3ea6d1e0 100644
--- a/libcxx/test/std/containers/associative/map/map.cons/iter_iter_comp_alloc.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.cons/iter_iter_comp_alloc.pass.cpp
@@ -22,7 +22,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<const int, double> V;
@@ -119,4 +119,6 @@ int main()
     }
 #endif
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.cons/move.pass.cpp b/libcxx/test/std/containers/associative/map/map.cons/move.pass.cpp
index f2f8dd8a976415b0484451955b2e3db6bb80cdd8..ecf8c9dabfd1d2b7d0fd402a56044986236b1ea2 100644
--- a/libcxx/test/std/containers/associative/map/map.cons/move.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.cons/move.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::pair<const int, double> V;
     {
@@ -114,4 +114,6 @@ int main()
         assert(mo.size() == 0);
         assert(distance(mo.begin(), mo.end()) == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.cons/move_alloc.pass.cpp b/libcxx/test/std/containers/associative/map/map.cons/move_alloc.pass.cpp
index cec9253561a32e33c92fa63a911148d9f02806a7..aa87e9ff07ab2d600c2d1bc5419f2a1c7c1cd5a7 100644
--- a/libcxx/test/std/containers/associative/map/map.cons/move_alloc.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.cons/move_alloc.pass.cpp
@@ -24,7 +24,7 @@
 #include "min_allocator.h"
 #include "Counter.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<MoveOnly, MoveOnly> V;
@@ -268,4 +268,6 @@ int main()
         assert(m3.key_comp() == C(5));
         LIBCPP_ASSERT(m1.empty());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.cons/move_assign.pass.cpp b/libcxx/test/std/containers/associative/map/map.cons/move_assign.pass.cpp
index be06d49c958a281555e5a825edc908730433cf26..758d0f83f86cb7c85aed4a3efdac6a62e34ad202 100644
--- a/libcxx/test/std/containers/associative/map/map.cons/move_assign.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.cons/move_assign.pass.cpp
@@ -22,7 +22,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<MoveOnly, MoveOnly> V;
@@ -184,4 +184,6 @@ int main()
         assert(m3.key_comp() == C(5));
         assert(m1.empty());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.cons/move_assign_noexcept.pass.cpp b/libcxx/test/std/containers/associative/map/map.cons/move_assign_noexcept.pass.cpp
index 42bc980b7e0185fe2b0f00257cb94ce057741d57..fcb92607163edbd8431ee5237d606900bd95e60a 100644
--- a/libcxx/test/std/containers/associative/map/map.cons/move_assign_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.cons/move_assign_noexcept.pass.cpp
@@ -33,7 +33,7 @@ struct some_comp
     bool operator()(const T&, const T&) const { return false; }
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::pair<const MoveOnly, MoveOnly> V;
     {
@@ -54,4 +54,6 @@ int main()
         typedef std::map<MoveOnly, MoveOnly, some_comp<MoveOnly>> C;
         static_assert(!std::is_nothrow_move_assignable<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.cons/move_noexcept.pass.cpp b/libcxx/test/std/containers/associative/map/map.cons/move_noexcept.pass.cpp
index dd61439ca5f79f8afc1c241d11da02c4126c9891..44b2b7e22b617af8164f2e44127c52fdfd4b2129 100644
--- a/libcxx/test/std/containers/associative/map/map.cons/move_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.cons/move_noexcept.pass.cpp
@@ -31,7 +31,7 @@ struct some_comp
     bool operator()(const T&, const T&) const { return false; }
 };
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     typedef std::pair<const MoveOnly, MoveOnly> V;
@@ -52,4 +52,6 @@ int main()
         typedef std::map<MoveOnly, MoveOnly, some_comp<MoveOnly>> C;
         static_assert(!std::is_nothrow_move_constructible<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.erasure/erase_if.pass.cpp b/libcxx/test/std/containers/associative/map/map.erasure/erase_if.pass.cpp
index af7accdffc039e49dc56a8e59ec64613d599af54..88a958368280ae65d682701d5b7fe1b668b5a6e0 100644
--- a/libcxx/test/std/containers/associative/map/map.erasure/erase_if.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.erasure/erase_if.pass.cpp
@@ -66,7 +66,7 @@ void test()
     test0<S>({1,2,3}, False, {1,2,3});
 }
 
-int main()
+int main(int, char**)
 {
     test<std::map<int, int>>();
     test<std::map<int, int, std::less<int>, min_allocator<std::pair<const int, int>>>> ();
@@ -74,5 +74,7 @@ int main()
 
     test<std::map<long, short>>();
     test<std::map<short, double>>();
+
+  return 0;
 }
 
diff --git a/libcxx/test/std/containers/associative/map/map.modifiers/clear.pass.cpp b/libcxx/test/std/containers/associative/map/map.modifiers/clear.pass.cpp
index 895a8115aa064b84e55771e4a45ac314e91de237..5c6d00e9f3a8afcf36a06d379aea31171c74d67e 100644
--- a/libcxx/test/std/containers/associative/map/map.modifiers/clear.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.modifiers/clear.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::map<int, double> M;
@@ -62,4 +62,6 @@ int main()
         assert(m.size() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.modifiers/emplace.pass.cpp b/libcxx/test/std/containers/associative/map/map.modifiers/emplace.pass.cpp
index 8680ab8213b60d72a93c9a06671c4f16584416d9..382e5c8badf845cf3d39c6079394c2ed51d74795 100644
--- a/libcxx/test/std/containers/associative/map/map.modifiers/emplace.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.modifiers/emplace.pass.cpp
@@ -23,7 +23,7 @@
 #include "DefaultOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::map<int, DefaultOnly> M;
@@ -159,4 +159,6 @@ int main()
         assert(m.begin()->first == 2);
         assert(m.begin()->second == 3.5);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.modifiers/emplace_hint.pass.cpp b/libcxx/test/std/containers/associative/map/map.modifiers/emplace_hint.pass.cpp
index 1c649093fe8aab61e65d11c16032d1cd47b1da9f..516d88054b776638dac56ae5450a814ee97e2267 100644
--- a/libcxx/test/std/containers/associative/map/map.modifiers/emplace_hint.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.modifiers/emplace_hint.pass.cpp
@@ -22,7 +22,7 @@
 #include "DefaultOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::map<int, DefaultOnly> M;
@@ -154,4 +154,6 @@ int main()
         assert(m.begin()->first == 2);
         assert(m.begin()->second == 3.5);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.modifiers/erase_iter.pass.cpp b/libcxx/test/std/containers/associative/map/map.modifiers/erase_iter.pass.cpp
index 57de16478fa58e90a0de69a8f244a51a6930aa24..0f23ef638101a4e3ccbbd49e7a1b6fbc1cee4161 100644
--- a/libcxx/test/std/containers/associative/map/map.modifiers/erase_iter.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.modifiers/erase_iter.pass.cpp
@@ -25,7 +25,7 @@ struct TemplateConstructor
 
 bool operator<(const TemplateConstructor&, const TemplateConstructor&) { return false; }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::map<int, double> M;
@@ -255,4 +255,6 @@ int main()
             c.erase(it);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.modifiers/erase_iter_iter.pass.cpp b/libcxx/test/std/containers/associative/map/map.modifiers/erase_iter_iter.pass.cpp
index 875fab5389724ee8e7bf23a713b08e5e385a0149..71fa96ce11b7e2a30c9145fa9ce54ca1c37c19e7 100644
--- a/libcxx/test/std/containers/associative/map/map.modifiers/erase_iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.modifiers/erase_iter_iter.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::map<int, double> M;
@@ -153,4 +153,6 @@ int main()
         assert(i == m.end());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.modifiers/erase_key.pass.cpp b/libcxx/test/std/containers/associative/map/map.modifiers/erase_key.pass.cpp
index 23fae9a6079881672caae12748aab4e26dde8451..da96499b09fb5a4aa6cd797e4b27ada00d03cf60 100644
--- a/libcxx/test/std/containers/associative/map/map.modifiers/erase_key.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.modifiers/erase_key.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::map<int, double> M;
@@ -271,4 +271,6 @@ int main()
         assert(s == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.modifiers/extract_iterator.pass.cpp b/libcxx/test/std/containers/associative/map/map.modifiers/extract_iterator.pass.cpp
index 95ba2b711b940c7032ffd05019219ced2ebfac0e..f2b67c9ff630a866646f0045cdd762bcef6c8bef 100644
--- a/libcxx/test/std/containers/associative/map/map.modifiers/extract_iterator.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.modifiers/extract_iterator.pass.cpp
@@ -40,7 +40,7 @@ void test(Container& c)
     assert(c.size() == 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
         using map_type = std::map<int, int>;
@@ -63,4 +63,6 @@ int main()
         min_alloc_map m = {{1, 1}, {2, 2}, {3, 3}, {4, 4}, {5, 5}, {6, 6}};
         test(m);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.modifiers/extract_key.pass.cpp b/libcxx/test/std/containers/associative/map/map.modifiers/extract_key.pass.cpp
index 70afd45ffb6f4dbaa34854ff00132ab13500cd2d..018e9acf8986352f656e33ba462019a78bfd7b61 100644
--- a/libcxx/test/std/containers/associative/map/map.modifiers/extract_key.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.modifiers/extract_key.pass.cpp
@@ -45,7 +45,7 @@ void test(Container& c, KeyTypeIter first, KeyTypeIter last)
     }
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::map<int, int> m = {{1,1}, {2,2}, {3,3}, {4,4}, {5,5}, {6,6}};
@@ -72,4 +72,6 @@ int main()
         int keys[] = {1, 2, 3, 4, 5, 6};
         test(m, std::begin(keys), std::end(keys));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.modifiers/insert_and_emplace_allocator_requirements.pass.cpp b/libcxx/test/std/containers/associative/map/map.modifiers/insert_and_emplace_allocator_requirements.pass.cpp
index 9adb3d61957d0d7c15b8295657f10b6978fd128f..f3e84002123c9db756a0f676c6e1aaff94676447 100644
--- a/libcxx/test/std/containers/associative/map/map.modifiers/insert_and_emplace_allocator_requirements.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.modifiers/insert_and_emplace_allocator_requirements.pass.cpp
@@ -21,10 +21,12 @@
 #include "container_test_types.h"
 #include "../../../map_allocator_requirement_test_templates.h"
 
-int main()
+int main(int, char**)
 {
   testMapInsert<TCT::map<> >();
   testMapInsertHint<TCT::map<> >();
   testMapEmplace<TCT::map<> >();
   testMapEmplaceHint<TCT::map<> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.modifiers/insert_cv.pass.cpp b/libcxx/test/std/containers/associative/map/map.modifiers/insert_cv.pass.cpp
index 50801f72183c33bd65900e641798eaa75deba254..079b0eaca011a020e0141d22f8b1944aa1ba1b58 100644
--- a/libcxx/test/std/containers/associative/map/map.modifiers/insert_cv.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.modifiers/insert_cv.pass.cpp
@@ -59,7 +59,7 @@ void do_insert_cv_test()
     assert(r.first->second == 3.5);
 }
 
-int main()
+int main(int, char**)
 {
     do_insert_cv_test<std::map<int, double> >();
 #if TEST_STD_VER >= 11
@@ -68,4 +68,6 @@ int main()
         do_insert_cv_test<M>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.modifiers/insert_initializer_list.pass.cpp b/libcxx/test/std/containers/associative/map/map.modifiers/insert_initializer_list.pass.cpp
index 124a40c330e0e3064e7d80b30bc2abe659ce867b..ea6c1380054ae2914638267a34b11af15042dd52 100644
--- a/libcxx/test/std/containers/associative/map/map.modifiers/insert_initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.modifiers/insert_initializer_list.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<const int, double> V;
@@ -65,4 +65,6 @@ int main()
     assert(*next(m.begin()) == V(2, 1));
     assert(*next(m.begin(), 2) == V(3, 1));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.modifiers/insert_iter_cv.pass.cpp b/libcxx/test/std/containers/associative/map/map.modifiers/insert_iter_cv.pass.cpp
index f993bc2027f88c1dcbeb37273b08bbcab958787f..a49a28c67bf530a030c248aaa358fc09872af60d 100644
--- a/libcxx/test/std/containers/associative/map/map.modifiers/insert_iter_cv.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.modifiers/insert_iter_cv.pass.cpp
@@ -55,7 +55,7 @@ void do_insert_iter_cv_test()
     assert(r->second == 3.5);
 }
 
-int main()
+int main(int, char**)
 {
     do_insert_iter_cv_test<std::map<int, double> >();
 #if TEST_STD_VER >= 11
@@ -64,4 +64,6 @@ int main()
         do_insert_iter_cv_test<M>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.modifiers/insert_iter_iter.pass.cpp b/libcxx/test/std/containers/associative/map/map.modifiers/insert_iter_iter.pass.cpp
index 6315bc40ef8b21fce9dc39fcf578071df13b7b1b..a6a7763363b04fd534c7a30e2cfc5176c0c63d00 100644
--- a/libcxx/test/std/containers/associative/map/map.modifiers/insert_iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.modifiers/insert_iter_iter.pass.cpp
@@ -19,7 +19,7 @@
 #include "test_iterators.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::map<int, double> M;
@@ -73,4 +73,6 @@ int main()
         assert(next(m.begin(), 2)->second == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.modifiers/insert_iter_rv.pass.cpp b/libcxx/test/std/containers/associative/map/map.modifiers/insert_iter_rv.pass.cpp
index 45665a411c39f554a2ca3faf13c7175737a427fb..8cbbebe5d3c20ab4fd38adba7681af52f3f7f757 100644
--- a/libcxx/test/std/containers/associative/map/map.modifiers/insert_iter_rv.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.modifiers/insert_iter_rv.pass.cpp
@@ -53,7 +53,7 @@ void do_insert_iter_rv_test()
     assert(r->first == 3);
     assert(r->second == 3);
 }
-int main()
+int main(int, char**)
 {
     do_insert_iter_rv_test<std::map<int, MoveOnly>, std::pair<int, MoveOnly>>();
     do_insert_iter_rv_test<std::map<int, MoveOnly>, std::pair<const int, MoveOnly>>();
@@ -94,4 +94,6 @@ int main()
         assert(r->second == 3);
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.modifiers/insert_node_type.pass.cpp b/libcxx/test/std/containers/associative/map/map.modifiers/insert_node_type.pass.cpp
index 3ad5f46b43b47ac180f2e88614f305f4598a41f4..f3f1662600e155022b93f12d0ad200c096bb37e3 100644
--- a/libcxx/test/std/containers/associative/map/map.modifiers/insert_node_type.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.modifiers/insert_node_type.pass.cpp
@@ -75,10 +75,12 @@ void test(Container& c)
     }
 }
 
-int main()
+int main(int, char**)
 {
     std::map<int, int> m;
     test(m);
     std::map<int, int, std::less<int>, min_allocator<std::pair<const int, int>>> m2;
     test(m2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.modifiers/insert_node_type_hint.pass.cpp b/libcxx/test/std/containers/associative/map/map.modifiers/insert_node_type_hint.pass.cpp
index 41d264f3f7bb7289e59eb205c5136e7a24bd8665..084f7ee2c74ab5ffbb4bffd1d835c9083e8fa604 100644
--- a/libcxx/test/std/containers/associative/map/map.modifiers/insert_node_type_hint.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.modifiers/insert_node_type_hint.pass.cpp
@@ -54,10 +54,12 @@ void test(Container& c)
     }
 }
 
-int main()
+int main(int, char**)
 {
     std::map<int, int> m;
     test(m);
     std::map<int, int, std::less<int>, min_allocator<std::pair<const int, int>>> m2;
     test(m2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.modifiers/insert_or_assign.pass.cpp b/libcxx/test/std/containers/associative/map/map.modifiers/insert_or_assign.pass.cpp
index 69caa8434a4c0f1b24c69c77617be0604e376477..bd9625a09501b35762dce47520183c64e440c95e 100644
--- a/libcxx/test/std/containers/associative/map/map.modifiers/insert_or_assign.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.modifiers/insert_or_assign.pass.cpp
@@ -56,7 +56,7 @@ public:
 };
 
 
-int main()
+int main(int, char**)
 {
     { // pair<iterator, bool> insert_or_assign(const key_type& k, M&& obj);
         typedef std::map<int, Moveable> M;
@@ -181,4 +181,6 @@ int main()
         assert(r->first.get()  == 3);  // key
         assert(r->second.get() == 5);  // value
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.modifiers/insert_rv.pass.cpp b/libcxx/test/std/containers/associative/map/map.modifiers/insert_rv.pass.cpp
index 439adfde27f16a7027610cbe21b7577965f63f6c..e6fb13ee32ce732ece11151f08d55efb33dfcf3c 100644
--- a/libcxx/test/std/containers/associative/map/map.modifiers/insert_rv.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.modifiers/insert_rv.pass.cpp
@@ -59,7 +59,7 @@ void do_insert_rv_test()
     assert(r.first->second == 3);
 }
 
-int main()
+int main(int, char**)
 {
     do_insert_rv_test<std::map<int, MoveOnly>, std::pair<int, MoveOnly>>();
     do_insert_rv_test<std::map<int, MoveOnly>, std::pair<const int, MoveOnly>>();
@@ -103,4 +103,6 @@ int main()
         assert(r.first->first == 3);
         assert(r.first->second == 3);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.modifiers/merge.pass.cpp b/libcxx/test/std/containers/associative/map/map.modifiers/merge.pass.cpp
index 1cef30944a801ff4ea755ed843ec03726c734d4a..ae943df6a452bba7029393d0b613611ba8de0f63 100644
--- a/libcxx/test/std/containers/associative/map/map.modifiers/merge.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.modifiers/merge.pass.cpp
@@ -49,7 +49,7 @@ struct throw_comparator
 };
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         std::map<int, int> src{{1, 0}, {3, 0}, {5, 0}};
@@ -146,4 +146,5 @@ int main()
             first.merge(std::move(second));
         }
     }
+    return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.modifiers/try.emplace.pass.cpp b/libcxx/test/std/containers/associative/map/map.modifiers/try.emplace.pass.cpp
index 43d5c3cac414a48f8ae695e0b72a995f94b1fcd8..fe9484a3ce3b18c29b1fbc8390fcaf004a9d8d9b 100644
--- a/libcxx/test/std/containers/associative/map/map.modifiers/try.emplace.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.modifiers/try.emplace.pass.cpp
@@ -54,7 +54,7 @@ public:
 };
 
 
-int main()
+int main(int, char**)
 {
     { // pair<iterator, bool> try_emplace(const key_type& k, Args&&... args);
         typedef std::map<int, Moveable> M;
@@ -178,4 +178,6 @@ int main()
         assert(r->first.get()  == 3); // key
         assert(r->second.get() == 4); // value
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.ops/count.pass.cpp b/libcxx/test/std/containers/associative/map/map.ops/count.pass.cpp
index 9ac980670de342e45bd0080c1c3c5389d51879d4..8abae288bd8efe863211844e47e420adaffa32ab 100644
--- a/libcxx/test/std/containers/associative/map/map.ops/count.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.ops/count.pass.cpp
@@ -20,7 +20,7 @@
 #include "private_constructor.hpp"
 #include "is_transparent.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<const int, double> V;
@@ -190,4 +190,6 @@ int main()
     assert(r == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.ops/count0.pass.cpp b/libcxx/test/std/containers/associative/map/map.ops/count0.pass.cpp
index eeaa41a00b373f956687e8c942e3e713d6d9dea0..cce0444fdc331529829930bbe423c67cb9994ca7 100644
--- a/libcxx/test/std/containers/associative/map/map.ops/count0.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.ops/count0.pass.cpp
@@ -25,7 +25,7 @@
 
 #include "is_transparent.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::map<int, double, transparent_less> M;
@@ -35,4 +35,6 @@ int main()
     typedef std::map<int, double, transparent_less_not_referenceable> M;
     assert(M().count(C2Int{5}) == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.ops/count1.fail.cpp b/libcxx/test/std/containers/associative/map/map.ops/count1.fail.cpp
index 049ee980a8b1cd58c9b9560634c06a04355f1a62..42dc59c27891f0723368b6133d1cd5b17f93cc70 100644
--- a/libcxx/test/std/containers/associative/map/map.ops/count1.fail.cpp
+++ b/libcxx/test/std/containers/associative/map/map.ops/count1.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::map<int, double, transparent_less_no_type> M;
diff --git a/libcxx/test/std/containers/associative/map/map.ops/count2.fail.cpp b/libcxx/test/std/containers/associative/map/map.ops/count2.fail.cpp
index 6b4c07572f9923f390285d5bde293c5cb7451608..1fe6b927d8deefeda10ebc246fd505c10963c485 100644
--- a/libcxx/test/std/containers/associative/map/map.ops/count2.fail.cpp
+++ b/libcxx/test/std/containers/associative/map/map.ops/count2.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::map<int, double, transparent_less_private> M;
diff --git a/libcxx/test/std/containers/associative/map/map.ops/count3.fail.cpp b/libcxx/test/std/containers/associative/map/map.ops/count3.fail.cpp
index 525c57cefdd68a3771c5fec25a1c24833326f09c..3fd930eb254222ada6f43b7f8a1d67a728064d16 100644
--- a/libcxx/test/std/containers/associative/map/map.ops/count3.fail.cpp
+++ b/libcxx/test/std/containers/associative/map/map.ops/count3.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::map<int, double, transparent_less_not_a_type> M;
diff --git a/libcxx/test/std/containers/associative/map/map.ops/count_transparent.pass.cpp b/libcxx/test/std/containers/associative/map/map.ops/count_transparent.pass.cpp
index fb33d3b0adf3a70d6e599d1e3902b581f6a33dbd..fa649024269089224d163d0e77aa0408d14d1caf 100644
--- a/libcxx/test/std/containers/associative/map/map.ops/count_transparent.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.ops/count_transparent.pass.cpp
@@ -40,10 +40,12 @@ struct Comp {
   }
 };
 
-int main() {
+int main(int, char**) {
   std::map<std::pair<int, int>, int, Comp> s{
       {{2, 1}, 1}, {{1, 2}, 2}, {{1, 3}, 3}, {{1, 4}, 4}, {{2, 2}, 5}};
 
   auto cnt = s.count(1);
   assert(cnt == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.ops/equal_range.pass.cpp b/libcxx/test/std/containers/associative/map/map.ops/equal_range.pass.cpp
index 3c0c16fb5c2599d522ea437ee98dd28c44cbd68a..c46e52c711c57fe80dc1f5993c7c9a7525055023 100644
--- a/libcxx/test/std/containers/associative/map/map.ops/equal_range.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.ops/equal_range.pass.cpp
@@ -21,7 +21,7 @@
 #include "private_constructor.hpp"
 #include "is_transparent.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<const int, double> V;
@@ -487,4 +487,6 @@ int main()
     assert(r.second == next(m.begin(), 8));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.ops/equal_range0.pass.cpp b/libcxx/test/std/containers/associative/map/map.ops/equal_range0.pass.cpp
index 27dac20aed6a861558dc4d96df9dabc6df1ea7f8..22f067a2a70cc37d2b6c601d065bfa84520d644c 100644
--- a/libcxx/test/std/containers/associative/map/map.ops/equal_range0.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.ops/equal_range0.pass.cpp
@@ -25,7 +25,7 @@
 
 #include "is_transparent.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::map<int, double, transparent_less> M;
@@ -41,4 +41,6 @@ int main()
     P result = example.equal_range(C2Int{5});
     assert(result.first == result.second);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.ops/equal_range1.fail.cpp b/libcxx/test/std/containers/associative/map/map.ops/equal_range1.fail.cpp
index 629541c1d634332feac6aebf13ab5b73f45ff4d3..f8ccfc3d8a56b29e2737e439f6eb541b8dead221 100644
--- a/libcxx/test/std/containers/associative/map/map.ops/equal_range1.fail.cpp
+++ b/libcxx/test/std/containers/associative/map/map.ops/equal_range1.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::map<int, double, transparent_less_no_type> M;
diff --git a/libcxx/test/std/containers/associative/map/map.ops/equal_range2.fail.cpp b/libcxx/test/std/containers/associative/map/map.ops/equal_range2.fail.cpp
index db3fe9eea617f2b11523d29994be003d44c38691..dcde9fc2e19c8901bbb1d3897aab40384c016e80 100644
--- a/libcxx/test/std/containers/associative/map/map.ops/equal_range2.fail.cpp
+++ b/libcxx/test/std/containers/associative/map/map.ops/equal_range2.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::map<int, double, transparent_less_private> M;
diff --git a/libcxx/test/std/containers/associative/map/map.ops/equal_range3.fail.cpp b/libcxx/test/std/containers/associative/map/map.ops/equal_range3.fail.cpp
index bdd1ae681406527ca5ef38f0d7fd3a2de76a6b24..f773c482c9f52d93fbd27fc8e9c9da657772f1d5 100644
--- a/libcxx/test/std/containers/associative/map/map.ops/equal_range3.fail.cpp
+++ b/libcxx/test/std/containers/associative/map/map.ops/equal_range3.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::map<int, double, transparent_less_not_a_type> M;
diff --git a/libcxx/test/std/containers/associative/map/map.ops/equal_range_transparent.pass.cpp b/libcxx/test/std/containers/associative/map/map.ops/equal_range_transparent.pass.cpp
index 4387967eb1fc837bd6171cc9712cab588c56adbc..4422135616515b8e68bde29fbb0c64e7d9002e96 100644
--- a/libcxx/test/std/containers/associative/map/map.ops/equal_range_transparent.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.ops/equal_range_transparent.pass.cpp
@@ -43,7 +43,7 @@ struct Comp {
   }
 };
 
-int main() {
+int main(int, char**) {
   std::map<std::pair<int, int>, int, Comp> s{
       {{2, 1}, 1}, {{1, 2}, 2}, {{1, 3}, 3}, {{1, 4}, 4}, {{2, 2}, 5}};
 
@@ -56,4 +56,6 @@ int main() {
   }
 
   assert(nels == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.ops/find.pass.cpp b/libcxx/test/std/containers/associative/map/map.ops/find.pass.cpp
index ca01e839c13780582fda44addf50c69ae3f1839e..bcf498ecf23e01d460964370ec3ee0c38a56cb0a 100644
--- a/libcxx/test/std/containers/associative/map/map.ops/find.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.ops/find.pass.cpp
@@ -21,7 +21,7 @@
 #include "private_constructor.hpp"
 #include "is_transparent.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<const int, double> V;
@@ -257,4 +257,6 @@ int main()
     assert(r == next(m.begin(), 8));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.ops/find0.pass.cpp b/libcxx/test/std/containers/associative/map/map.ops/find0.pass.cpp
index a684738df96d22fe0ee9940055981bee09a65d18..affc61efb545b99e341cf5bd16465671e1d29f6b 100644
--- a/libcxx/test/std/containers/associative/map/map.ops/find0.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.ops/find0.pass.cpp
@@ -25,7 +25,7 @@
 
 #include "is_transparent.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::map<int, double, transparent_less> M;
@@ -37,4 +37,6 @@ int main()
     M example;
     assert(example.find(C2Int{5}) == example.end());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.ops/find1.fail.cpp b/libcxx/test/std/containers/associative/map/map.ops/find1.fail.cpp
index 1cad78a398a2eff1cfc942dd6b6b8618c2c8348b..6bd1a95abc58c49a67bc091b5ba2d4fa57167ec7 100644
--- a/libcxx/test/std/containers/associative/map/map.ops/find1.fail.cpp
+++ b/libcxx/test/std/containers/associative/map/map.ops/find1.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::map<int, double, transparent_less_no_type> M;
diff --git a/libcxx/test/std/containers/associative/map/map.ops/find2.fail.cpp b/libcxx/test/std/containers/associative/map/map.ops/find2.fail.cpp
index cd88583160b19f6435fcbf84901fcfb25f4e6b53..7af1c0eb8b252d87b8203ba9086823d66328a326 100644
--- a/libcxx/test/std/containers/associative/map/map.ops/find2.fail.cpp
+++ b/libcxx/test/std/containers/associative/map/map.ops/find2.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::map<int, double, transparent_less_private> M;
diff --git a/libcxx/test/std/containers/associative/map/map.ops/find3.fail.cpp b/libcxx/test/std/containers/associative/map/map.ops/find3.fail.cpp
index 62a4a648f703f6a47cff1f3976db778ec90014f0..32164fd3a97bba9fc94bca11c8956dae69a4d3ce 100644
--- a/libcxx/test/std/containers/associative/map/map.ops/find3.fail.cpp
+++ b/libcxx/test/std/containers/associative/map/map.ops/find3.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::map<int, double, transparent_less_not_a_type> M;
diff --git a/libcxx/test/std/containers/associative/map/map.ops/lower_bound.pass.cpp b/libcxx/test/std/containers/associative/map/map.ops/lower_bound.pass.cpp
index 3572b08f7fae5a2a7c3545fb6b328459d307887f..5b1c925a6c47d41398cf1a1d7c1c8ab94a01a7e0 100644
--- a/libcxx/test/std/containers/associative/map/map.ops/lower_bound.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.ops/lower_bound.pass.cpp
@@ -21,7 +21,7 @@
 #include "private_constructor.hpp"
 #include "is_transparent.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<const int, double> V;
@@ -369,4 +369,6 @@ int main()
     assert(r == next(m.begin(), 8));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.ops/lower_bound0.pass.cpp b/libcxx/test/std/containers/associative/map/map.ops/lower_bound0.pass.cpp
index 50752e8da33882d5c9641d5acb5cf69a5ee37904..a92790f2bd6fcd99ca7e6ffe9f7c367fe388acb3 100644
--- a/libcxx/test/std/containers/associative/map/map.ops/lower_bound0.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.ops/lower_bound0.pass.cpp
@@ -25,7 +25,7 @@
 
 #include "is_transparent.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::map<int, double, transparent_less> M;
@@ -37,4 +37,6 @@ int main()
     M example;
     assert(example.lower_bound(C2Int{5}) == example.end());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.ops/lower_bound1.fail.cpp b/libcxx/test/std/containers/associative/map/map.ops/lower_bound1.fail.cpp
index 095e1b3b3ed6ca20fb7415503d2768ff2d91a630..efdc762e8b7882c1157f6adc7d8212ed957d81f9 100644
--- a/libcxx/test/std/containers/associative/map/map.ops/lower_bound1.fail.cpp
+++ b/libcxx/test/std/containers/associative/map/map.ops/lower_bound1.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::map<int, double, transparent_less_no_type> M;
diff --git a/libcxx/test/std/containers/associative/map/map.ops/lower_bound2.fail.cpp b/libcxx/test/std/containers/associative/map/map.ops/lower_bound2.fail.cpp
index 455e8fa9999e900914f9e35cc8aae53eef0a1edc..362b223ffa06290593f350c73ce04c306caefbc4 100644
--- a/libcxx/test/std/containers/associative/map/map.ops/lower_bound2.fail.cpp
+++ b/libcxx/test/std/containers/associative/map/map.ops/lower_bound2.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::map<int, double, transparent_less_private> M;
diff --git a/libcxx/test/std/containers/associative/map/map.ops/lower_bound3.fail.cpp b/libcxx/test/std/containers/associative/map/map.ops/lower_bound3.fail.cpp
index 8c9ac1d6509910c7c22a6a6a40876cea4bf62adc..cc8bdf92af743745b99fa9ddf1c2cc985cccc4d2 100644
--- a/libcxx/test/std/containers/associative/map/map.ops/lower_bound3.fail.cpp
+++ b/libcxx/test/std/containers/associative/map/map.ops/lower_bound3.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::map<int, double, transparent_less_not_a_type> M;
diff --git a/libcxx/test/std/containers/associative/map/map.ops/upper_bound.pass.cpp b/libcxx/test/std/containers/associative/map/map.ops/upper_bound.pass.cpp
index 58ccd7f4343fc276c9fc127da243ebac57d0dc47..c7fdd879a35e8caa9b3fb3cee3258dcc956dbfef 100644
--- a/libcxx/test/std/containers/associative/map/map.ops/upper_bound.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.ops/upper_bound.pass.cpp
@@ -20,7 +20,7 @@
 #include "min_allocator.h"
 #include "private_constructor.hpp"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<const int, double> V;
@@ -332,4 +332,6 @@ int main()
     assert(r == next(m.begin(), 8));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.ops/upper_bound0.pass.cpp b/libcxx/test/std/containers/associative/map/map.ops/upper_bound0.pass.cpp
index 723cdc6df6f439d1e090872770c234ed06aac107..8f58df61b7d97a41c6f42925ae2ac125f5cf5f22 100644
--- a/libcxx/test/std/containers/associative/map/map.ops/upper_bound0.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.ops/upper_bound0.pass.cpp
@@ -25,7 +25,7 @@
 
 #include "is_transparent.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::map<int, double, transparent_less> M;
@@ -37,4 +37,6 @@ int main()
     M example;
     assert(example.upper_bound(C2Int{5}) == example.end());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.ops/upper_bound1.fail.cpp b/libcxx/test/std/containers/associative/map/map.ops/upper_bound1.fail.cpp
index fa4afc987c9d09356a43c03a615d570d6e208faf..8ed0eed59dc45bd80dd45406431e8f254fc26e2b 100644
--- a/libcxx/test/std/containers/associative/map/map.ops/upper_bound1.fail.cpp
+++ b/libcxx/test/std/containers/associative/map/map.ops/upper_bound1.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::map<int, double, transparent_less_no_type> M;
diff --git a/libcxx/test/std/containers/associative/map/map.ops/upper_bound2.fail.cpp b/libcxx/test/std/containers/associative/map/map.ops/upper_bound2.fail.cpp
index 5be763366c693e8757e4e83a8cb3a69bc819d8ea..d08b6c0f04e057776f358d1828341eb5c631ab8b 100644
--- a/libcxx/test/std/containers/associative/map/map.ops/upper_bound2.fail.cpp
+++ b/libcxx/test/std/containers/associative/map/map.ops/upper_bound2.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::map<int, double, transparent_less_private> M;
diff --git a/libcxx/test/std/containers/associative/map/map.ops/upper_bound3.fail.cpp b/libcxx/test/std/containers/associative/map/map.ops/upper_bound3.fail.cpp
index 773f114f9a6f00a5c1f1c7dda39e4a9d2b026042..df7cd226993210603ada22d96b96893993d511b0 100644
--- a/libcxx/test/std/containers/associative/map/map.ops/upper_bound3.fail.cpp
+++ b/libcxx/test/std/containers/associative/map/map.ops/upper_bound3.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::map<int, double, transparent_less_not_a_type> M;
diff --git a/libcxx/test/std/containers/associative/map/map.special/member_swap.pass.cpp b/libcxx/test/std/containers/associative/map/map.special/member_swap.pass.cpp
index 4f985bae3db55801af8417a388fac676e3f4247e..a41e43f7a06637facc381bb8a5019847c9473dc5 100644
--- a/libcxx/test/std/containers/associative/map/map.special/member_swap.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.special/member_swap.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::pair<const int, double> V;
     {
@@ -172,4 +172,6 @@ int main()
     }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.special/non_member_swap.pass.cpp b/libcxx/test/std/containers/associative/map/map.special/non_member_swap.pass.cpp
index aea80f9c3cab3d2ee11800b85971767d6d843379..811acc4573ee87f96734a7063360554b935c3a00 100644
--- a/libcxx/test/std/containers/associative/map/map.special/non_member_swap.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.special/non_member_swap.pass.cpp
@@ -20,7 +20,7 @@
 #include "../../../test_compare.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::pair<const int, double> V;
     {
@@ -277,4 +277,6 @@ int main()
         assert(m2.get_allocator() == A());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/map.special/swap_noexcept.pass.cpp b/libcxx/test/std/containers/associative/map/map.special/swap_noexcept.pass.cpp
index 346057415b2349a21bab65215255a5241a5db604..4e1497f7abe023ab87255c2afa418eb9eea0f476 100644
--- a/libcxx/test/std/containers/associative/map/map.special/swap_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/map.special/swap_noexcept.pass.cpp
@@ -91,7 +91,7 @@ struct some_alloc3
     typedef std::false_type is_always_equal;
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::pair<const MoveOnly, MoveOnly> V;
     {
@@ -138,4 +138,6 @@ int main()
 #endif // _LIBCPP_VERSION
 #endif
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/map/types.pass.cpp b/libcxx/test/std/containers/associative/map/types.pass.cpp
index f9f7abc28a83d6497c8f5f03cfa2fe4e94a01493..35fc067433f02481f4583275ce1cb1f9f0473294 100644
--- a/libcxx/test/std/containers/associative/map/types.pass.cpp
+++ b/libcxx/test/std/containers/associative/map/types.pass.cpp
@@ -33,7 +33,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::map<int, double> C;
@@ -66,4 +66,6 @@ int main()
     static_assert((std::is_same<C::difference_type, std::ptrdiff_t>::value), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/allocator_mismatch.fail.cpp b/libcxx/test/std/containers/associative/multimap/allocator_mismatch.fail.cpp
index f59df265af32590271c70635b904c3e21ab953f8..47dd64ebcaf5fb02ad023fe205f0225d1a92c202 100644
--- a/libcxx/test/std/containers/associative/multimap/allocator_mismatch.fail.cpp
+++ b/libcxx/test/std/containers/associative/multimap/allocator_mismatch.fail.cpp
@@ -11,7 +11,9 @@
 
 #include <map>
 
-int main()
+int main(int, char**)
 {
     std::multimap<int, int, std::less<int>, std::allocator<long> > m;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/empty.fail.cpp b/libcxx/test/std/containers/associative/multimap/empty.fail.cpp
index 91fc1026f371a34efb16536d1e5f4b10e93297a8..bc305b9cc8db49dea1949d500018be6f9ad44b10 100644
--- a/libcxx/test/std/containers/associative/multimap/empty.fail.cpp
+++ b/libcxx/test/std/containers/associative/multimap/empty.fail.cpp
@@ -20,8 +20,10 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     std::multimap<int, int> c;
     c.empty();  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/empty.pass.cpp b/libcxx/test/std/containers/associative/multimap/empty.pass.cpp
index a83e2265cfa603054d0f78bdac109d60da119360..12866a0f2d1c9aa0f142c3135668921105bf2648 100644
--- a/libcxx/test/std/containers/associative/multimap/empty.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/empty.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::multimap<int, double> M;
@@ -39,4 +39,6 @@ int main()
     assert(m.empty());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/incomplete_type.pass.cpp b/libcxx/test/std/containers/associative/multimap/incomplete_type.pass.cpp
index 5f83dce469e49ff123c911d4f2d15e0093012fc0..0132ce9fe12e7a4512f8d6a1fae7de3dbe17c9ea 100644
--- a/libcxx/test/std/containers/associative/multimap/incomplete_type.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/incomplete_type.pass.cpp
@@ -23,6 +23,8 @@ struct A {
 
 inline bool operator==(A const& L, A const& R) { return &L == &R; }
 inline bool operator<(A const& L, A const& R)  { return L.data < R.data; }
-int main() {
+int main(int, char**) {
     A a;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/iterator.pass.cpp b/libcxx/test/std/containers/associative/multimap/iterator.pass.cpp
index f27bce16d5c20867e48057f8e2bc5408ded50060..0a61531187e39cc5bac78fc4fc548cf312a245af 100644
--- a/libcxx/test/std/containers/associative/multimap/iterator.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/iterator.pass.cpp
@@ -32,7 +32,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<const int, double> V;
@@ -229,4 +229,6 @@ int main()
         assert (!(cii != ii1 ));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/max_size.pass.cpp b/libcxx/test/std/containers/associative/multimap/max_size.pass.cpp
index 106bb667ca7aa645cd66ab9acacd8064a77507af..a4537c3d1b2979c02859e38883abcfefb1e11f8e 100644
--- a/libcxx/test/std/containers/associative/multimap/max_size.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/max_size.pass.cpp
@@ -20,7 +20,7 @@
 #include "test_allocator.h"
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
   typedef std::pair<const int, int> KV;
   {
@@ -47,4 +47,6 @@ int main()
     assert(c.max_size() <= max_dist);
     assert(c.max_size() <= alloc_max_size(c.get_allocator()));
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.cons/alloc.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.cons/alloc.pass.cpp
index e8c35d5a881c24ec3f394b6299d6e954d203ccc8..6e7e3aa09723db28e88b75a41b3497144542de6f 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.cons/alloc.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.cons/alloc.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::less<int> C;
@@ -46,4 +46,6 @@ int main()
     assert(m.get_allocator() == A{});
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.cons/assign_initializer_list.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.cons/assign_initializer_list.pass.cpp
index 47e4e71a39fd71ed49ca1ba12fc44d5135a35da4..0374062515c681c5a1681a950267b14638a8f3a4 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.cons/assign_initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.cons/assign_initializer_list.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::multimap<int, double> C;
@@ -79,4 +79,6 @@ int main()
     assert(*++i == V(3, 1.5));
     assert(*++i == V(3, 2));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.cons/compare.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.cons/compare.pass.cpp
index 5b83bb0be1cfcfd2426b93f66ddb35db8a9811ec..54bf998ecdd11a67d460fe238cc32b3410580962 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.cons/compare.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.cons/compare.pass.cpp
@@ -20,7 +20,7 @@
 #include "../../../test_compare.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef test_compare<std::less<int> > C;
@@ -38,4 +38,6 @@ int main()
     assert(m.key_comp() == C(3));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.cons/compare_alloc.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.cons/compare_alloc.pass.cpp
index 1f11066f86e61b5c771cc47a6a3ac7706a45df3b..44942036c73bffbd92b6e1937334ce76f8f008ac 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.cons/compare_alloc.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.cons/compare_alloc.pass.cpp
@@ -19,7 +19,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef test_compare<std::less<int> > C;
@@ -50,4 +50,6 @@ int main()
     assert(m.get_allocator() == A{});
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.cons/compare_copy_constructible.fail.cpp b/libcxx/test/std/containers/associative/multimap/multimap.cons/compare_copy_constructible.fail.cpp
index 19276a0eef24590891e911bb773c09f2a1e578f1..23fe479f56cb2ae73284e90ec44b4013affa5266 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.cons/compare_copy_constructible.fail.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.cons/compare_copy_constructible.fail.cpp
@@ -23,6 +23,8 @@ private:
     };
 
 
-int main() {
+int main(int, char**) {
     std::multimap<int, int, Comp<int> > m;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.cons/copy.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.cons/copy.pass.cpp
index c691a196535226b91efcbb3a65895421c7902c88..d3b064256776ce4ea16f3d5ee8e818ad566ae0bd 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.cons/copy.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.cons/copy.pass.cpp
@@ -20,7 +20,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<const int, double> V;
@@ -99,4 +99,6 @@ int main()
         assert(mo.key_comp() == C(5));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.cons/copy_alloc.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.cons/copy_alloc.pass.cpp
index 3c549d6aed146edff45be7772f8ef498c9ec7e12..7144a25f9d44aec6f51ba3639ee62be57e734de9 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.cons/copy_alloc.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.cons/copy_alloc.pass.cpp
@@ -19,7 +19,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<const int, double> V;
@@ -98,4 +98,6 @@ int main()
     assert(mo.key_comp() == C(5));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.cons/copy_assign.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.cons/copy_assign.pass.cpp
index d49290868136bd4089f414c4b577062906a8ae81..6816a5ee43f0d2cd97478d0f559d2f29be40f639 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.cons/copy_assign.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.cons/copy_assign.pass.cpp
@@ -19,7 +19,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<const int, double> V;
@@ -121,4 +121,6 @@ int main()
         assert(mo.key_comp() == C(5));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.cons/default.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.cons/default.pass.cpp
index 6c59b603bdf860a6c853f006488345b1097c5811..6b33088434db581472bff21a23ad2ec767120333 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.cons/default.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.cons/default.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::multimap<int, double> m;
@@ -50,4 +50,6 @@ int main()
     assert(m.begin() == m.end());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.cons/default_noexcept.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.cons/default_noexcept.pass.cpp
index d55adedc906301ed9e27a5618ef985f71ad2378b..e5a28601eec9a08cba2f2ee05567d4ee1caaf377 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.cons/default_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.cons/default_noexcept.pass.cpp
@@ -33,7 +33,7 @@ struct some_comp
     bool operator()(const T&, const T&) const { return false; }
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::pair<const MoveOnly, MoveOnly> V;
 #if defined(_LIBCPP_VERSION)
@@ -54,4 +54,6 @@ int main()
         typedef std::multimap<MoveOnly, MoveOnly, some_comp<MoveOnly>> C;
         static_assert(!std::is_nothrow_default_constructible<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.cons/default_recursive.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.cons/default_recursive.pass.cpp
index 8d960dbe32daf025b7db757df9087ed6bf35040a..b51b6b63b7de8f0cea54a13280fcc8702667037f 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.cons/default_recursive.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.cons/default_recursive.pass.cpp
@@ -23,6 +23,8 @@ struct X
     std::multimap<int, X>::const_reverse_iterator cri;
 };
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.cons/dtor_noexcept.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.cons/dtor_noexcept.pass.cpp
index 01cdff8c3106c4ebd24e5ec8522d44d079658352..100746789ac271cce555468643e56bf545f70cc4 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.cons/dtor_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.cons/dtor_noexcept.pass.cpp
@@ -27,7 +27,7 @@ struct some_comp
     bool operator()(const T&, const T&) const { return false; }
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::pair<const MoveOnly, MoveOnly> V;
     {
@@ -48,4 +48,6 @@ int main()
         static_assert(!std::is_nothrow_destructible<C>::value, "");
     }
 #endif // _LIBCPP_VERSION
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.cons/initializer_list.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.cons/initializer_list.pass.cpp
index bd26b397c5df924109e0ac85073307068e6073af..2642ba6a8eeb6c0f044565fa8fbec84728b6318b 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.cons/initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.cons/initializer_list.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::multimap<int, double> C;
@@ -77,4 +77,6 @@ int main()
     assert(*++i == V(3, 1.5));
     assert(*++i == V(3, 2));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.cons/initializer_list_compare.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.cons/initializer_list_compare.pass.cpp
index a3f29e6079468be2c735aadc3f8ac07f29786e7e..c8e2d293fa0781115822e19710edc04ece5ac4d0 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.cons/initializer_list_compare.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.cons/initializer_list_compare.pass.cpp
@@ -19,7 +19,7 @@
 #include "../../../test_compare.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef test_compare<std::less<int> > Cmp;
@@ -85,4 +85,6 @@ int main()
     assert(*++i == V(3, 2));
     assert(m.key_comp() == Cmp(4));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.cons/initializer_list_compare_alloc.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.cons/initializer_list_compare_alloc.pass.cpp
index 572a3cfb0b6e265f27e9395cc02e46737cdab52a..592dec9974974ee3a246981c991c4eb42505fbaf 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.cons/initializer_list_compare_alloc.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.cons/initializer_list_compare_alloc.pass.cpp
@@ -20,7 +20,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef test_compare<std::less<int> > Cmp;
@@ -155,4 +155,6 @@ int main()
     assert(m.key_comp() == Cmp(4));
     assert(m.get_allocator() == A{});
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.cons/iter_iter.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.cons/iter_iter.pass.cpp
index 0ea352404d1069f17c16e376912187c8b4506956..4d92b3d0b7d9493b8c8f64cc193d5c3773205eb7 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.cons/iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.cons/iter_iter.pass.cpp
@@ -19,7 +19,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<const int, double> V;
@@ -109,4 +109,6 @@ int main()
     }
 #endif
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.cons/iter_iter_comp.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.cons/iter_iter_comp.pass.cpp
index aa114a25a6e295ea43f792d76e8ad5b527a8d08d..d10904a4d448b6864ffd58e118c187ffd3b47c35 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.cons/iter_iter_comp.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.cons/iter_iter_comp.pass.cpp
@@ -20,7 +20,7 @@
 #include "../../../test_compare.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<const int, double> V;
@@ -82,4 +82,6 @@ int main()
     assert(*next(m.begin(), 8) == V(3, 2));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.cons/iter_iter_comp_alloc.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.cons/iter_iter_comp_alloc.pass.cpp
index 7d02c753935bd453f243a4cccf1da2df55b1c7ff..a71c757ffd72741342d6844adcef45eaed53731d 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.cons/iter_iter_comp_alloc.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.cons/iter_iter_comp_alloc.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<const int, double> V;
@@ -118,4 +118,6 @@ int main()
     assert(*next(m.begin(), 8) == V(3, 2));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.cons/move.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.cons/move.pass.cpp
index 324e0a140c5b3fd6176546aa5e6a1a031914f019..cef6857740c797b88902d1769bd89047b4eef0a6 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.cons/move.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.cons/move.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::pair<const int, double> V;
     {
@@ -126,4 +126,6 @@ int main()
         assert(mo.size() == 0);
         assert(distance(mo.begin(), mo.end()) == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.cons/move_alloc.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.cons/move_alloc.pass.cpp
index 3342a4edaab85114134f7d499c556adf5f8d0ed7..712afbeaa6ad4a1c94b2832605835037b7213049 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.cons/move_alloc.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.cons/move_alloc.pass.cpp
@@ -24,7 +24,7 @@
 #include "min_allocator.h"
 #include "Counter.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<MoveOnly, MoveOnly> V;
@@ -268,4 +268,6 @@ int main()
         assert(m3.key_comp() == C(5));
         LIBCPP_ASSERT(m1.empty());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.cons/move_assign.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.cons/move_assign.pass.cpp
index c1f8e7e5a64f0076aa177045646edb6730f1ff6b..386c11ecba2c9bd11eb34c04f9f98e51b908d1c0 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.cons/move_assign.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.cons/move_assign.pass.cpp
@@ -22,7 +22,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<MoveOnly, MoveOnly> V;
@@ -184,4 +184,6 @@ int main()
         assert(m3.key_comp() == C(5));
         assert(m1.empty());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.cons/move_assign_noexcept.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.cons/move_assign_noexcept.pass.cpp
index 41ea65853307d1399ab7f3f1297ad6d5ec966838..2afcc5e58f87b122bd714e911177bd99c007e65a 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.cons/move_assign_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.cons/move_assign_noexcept.pass.cpp
@@ -33,7 +33,7 @@ struct some_comp
     bool operator()(const T&, const T&) const { return false; }
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::pair<const MoveOnly, MoveOnly> V;
     {
@@ -54,4 +54,6 @@ int main()
         typedef std::multimap<MoveOnly, MoveOnly, some_comp<MoveOnly>> C;
         static_assert(!std::is_nothrow_move_assignable<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.cons/move_noexcept.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.cons/move_noexcept.pass.cpp
index b1c148a9fac86021318fc1a90de95e428004ed46..377167484205bc1725fb71ba7659f3e189a33161 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.cons/move_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.cons/move_noexcept.pass.cpp
@@ -31,7 +31,7 @@ struct some_comp
     bool operator()(const T&, const T&) const { return false; }
 };
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     typedef std::pair<const MoveOnly, MoveOnly> V;
@@ -52,4 +52,6 @@ int main()
         typedef std::multimap<MoveOnly, MoveOnly, some_comp<MoveOnly>> C;
         static_assert(!std::is_nothrow_move_constructible<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.erasure/erase_if.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.erasure/erase_if.pass.cpp
index dc448f58d9db0a9dff383517f8a6756bb4a1a895..15893f77b6372cb40f6421346725bbd5342936c8 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.erasure/erase_if.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.erasure/erase_if.pass.cpp
@@ -77,7 +77,7 @@ void test()
     test0<S>({1,2,3}, False, {1,2,3});
 }
 
-int main()
+int main(int, char**)
 {
     test<std::multimap<int, int>>();
     test<std::multimap<int, int, std::less<int>, min_allocator<std::pair<const int, int>>>> ();
@@ -85,4 +85,6 @@ int main()
 
     test<std::multimap<long, short>>();
     test<std::multimap<short, double>>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/clear.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/clear.pass.cpp
index 0cb5cb29b4232de462809a643f7111a1bd23f8e5..d05a13b5f191e34b9b486277e7ec500a316828ba 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/clear.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/clear.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::multimap<int, double> M;
@@ -62,4 +62,6 @@ int main()
         assert(m.size() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/emplace.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/emplace.pass.cpp
index 2780d3a53209803fb19a26b6c9953e42e5cbde78..76d9b171832b5ac0a9542aded9d9438c84a2a8f5 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/emplace.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/emplace.pass.cpp
@@ -22,7 +22,7 @@
 #include "DefaultOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::multimap<int, DefaultOnly> M;
@@ -144,4 +144,6 @@ int main()
         assert(m.begin()->first == 2);
         assert(m.begin()->second == 3.5);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/emplace_hint.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/emplace_hint.pass.cpp
index 49ee3069b28de2dd86f4e964ae430257765bd001..3ad09f38a70d4b3d8e260aec72f31b1906ff2bff 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/emplace_hint.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/emplace_hint.pass.cpp
@@ -22,7 +22,7 @@
 #include "DefaultOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::multimap<int, DefaultOnly> M;
@@ -154,4 +154,6 @@ int main()
         assert(m.begin()->first == 2);
         assert(m.begin()->second == 3.5);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/erase_iter.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/erase_iter.pass.cpp
index 62ab3f5fd3116093a389c506216701ee908f8f27..a0f70d640bd8a3692a084df29f063236f2daa695 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/erase_iter.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/erase_iter.pass.cpp
@@ -25,7 +25,7 @@ struct TemplateConstructor
 
 bool operator<(const TemplateConstructor&, const TemplateConstructor&) { return false; }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::multimap<int, double> M;
@@ -297,4 +297,6 @@ int main()
             c.erase(it);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/erase_iter_iter.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/erase_iter_iter.pass.cpp
index f561d149b53fc560f575376e61eb257fb9285c4c..deef1a1461dc69e8a85641a005677faf704e7939 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/erase_iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/erase_iter_iter.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::multimap<int, double> M;
@@ -153,4 +153,6 @@ int main()
         assert(i == m.end());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/erase_key.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/erase_key.pass.cpp
index f881c77c27a12344baae183761cccab22f8ee9a4..0ab1d4cb8abfdedbad0277bd65bdd9a638f9fe18 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/erase_key.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/erase_key.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::multimap<int, double> M;
@@ -149,4 +149,6 @@ int main()
         assert(i == 3);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/extract_iterator.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/extract_iterator.pass.cpp
index a0992d751575422e3ef9f3324bf373f2b9202a4e..fe3c7883244218a198a0997724cf4605680bb9f0 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/extract_iterator.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/extract_iterator.pass.cpp
@@ -40,7 +40,7 @@ void test(Container& c)
     assert(c.size() == 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
         using map_type = std::multimap<int, int>;
@@ -63,4 +63,6 @@ int main()
         min_alloc_map m = {{1, 1}, {2, 2}, {3, 3}, {4, 4}, {5, 5}, {6, 6}};
         test(m);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/extract_key.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/extract_key.pass.cpp
index 687043a4cc5f1a8c6751f9942bfc5eac38aa2b8a..e2a80dab25ff72e6703d95de85d96d6ef09a630d 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/extract_key.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/extract_key.pass.cpp
@@ -45,7 +45,7 @@ void test(Container& c, KeyTypeIter first, KeyTypeIter last)
     }
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::multimap<int, int> m = {{1,1}, {2,2}, {3,3}, {4,4}, {5,5}, {6,6}};
@@ -72,4 +72,6 @@ int main()
         int keys[] = {1, 2, 3, 4, 5, 6};
         test(m, std::begin(keys), std::end(keys));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_allocator_requirements.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_allocator_requirements.pass.cpp
index 008770cbfdd100f9ac66caaf3fce79d295a9de7f..9a791af57e61cffb4e58d2b23e8fc350a9086586 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_allocator_requirements.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_allocator_requirements.pass.cpp
@@ -20,8 +20,10 @@
 #include "../../../map_allocator_requirement_test_templates.h"
 
 
-int main()
+int main(int, char**)
 {
   testMultimapInsert<TCT::multimap<> >();
   testMultimapInsertHint<TCT::multimap<> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_cv.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_cv.pass.cpp
index 8c4e51b2481bdba79dd990a792d707d24c5085d2..b83034448a145d8b2c95287856d36342c4d92b61 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_cv.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_cv.pass.cpp
@@ -53,7 +53,7 @@ void do_insert_test() {
     assert(r->second == 3.5);
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::multimap<int, double> Container;
@@ -65,4 +65,6 @@ int main()
         do_insert_test<Container>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_initializer_list.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_initializer_list.pass.cpp
index 2da3e7d49419c2bdf20f99528c7122238db61165..33104ca88b5354bb00f52e6219791d217b8e3dd0 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_initializer_list.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::multimap<int, double> C;
@@ -85,4 +85,6 @@ int main()
     assert(*++i == V(3, 2));
     assert(*++i == V(3, 1.5));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_iter_cv.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_iter_cv.pass.cpp
index 946193446b5cc0359617bfea08de2ea01e198bf6..fb3283f838496da267b27ca0fd116d3f412c6800 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_iter_cv.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_iter_cv.pass.cpp
@@ -54,7 +54,7 @@ void do_insert_hint_test()
     assert(r->second == 4.5);
 }
 
-int main()
+int main(int, char**)
 {
     do_insert_hint_test<std::multimap<int, double> >();
 #if TEST_STD_VER >= 11
@@ -63,4 +63,6 @@ int main()
         do_insert_hint_test<M>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_iter_iter.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_iter_iter.pass.cpp
index f7a11f86c4f9377e6307f50f75a34707f237ef36..9533a62896d74885214470782e74ae4c84f41a95 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_iter_iter.pass.cpp
@@ -19,7 +19,7 @@
 #include "test_iterators.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::multimap<int, double> M;
@@ -97,4 +97,6 @@ int main()
         assert(next(m.begin(), 8)->second == 2);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_iter_rv.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_iter_rv.pass.cpp
index 0912136f1801114ef2fa878b7a8ee50da190b09c..5eea856a0d842fdfc6ad5836c241b81fb2e47173 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_iter_rv.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_iter_rv.pass.cpp
@@ -54,7 +54,7 @@ void do_insert_rv_test()
     assert(r->second == 2);
 }
 
-int main()
+int main(int, char**)
 {
     do_insert_rv_test<std::multimap<int, MoveOnly>, std::pair<int, MoveOnly> >();
     do_insert_rv_test<std::multimap<int, MoveOnly>, std::pair<const int, MoveOnly> >();
@@ -95,4 +95,6 @@ int main()
         assert(r->first == 3);
         assert(r->second == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_node_type.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_node_type.pass.cpp
index 71122d3a39a348ec2bea5b294f4304646ccb67b0..7fb62a7c16ee164f2ca0824ab4e2b6a07b5db109 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_node_type.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_node_type.pass.cpp
@@ -68,10 +68,12 @@ void test(Container& c)
     }
 }
 
-int main()
+int main(int, char**)
 {
     std::multimap<int, int> m;
     test(m);
     std::multimap<int, int, std::less<int>, min_allocator<std::pair<const int, int>>> m2;
     test(m2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_node_type_hint.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_node_type_hint.pass.cpp
index edc7d2bd326e5d4bf442793ee542f970988dcf34..847a701369268730123813b0196ed8546c52e091 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_node_type_hint.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_node_type_hint.pass.cpp
@@ -54,10 +54,12 @@ void test(Container& c)
     }
 }
 
-int main()
+int main(int, char**)
 {
     std::multimap<int, int> m;
     test(m);
     std::multimap<int, int, std::less<int>, min_allocator<std::pair<const int, int>>> m2;
     test(m2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_rv.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_rv.pass.cpp
index 041ce97a63d40b55bfae40ade5010f9b08aaa38d..05393345c12e3dea5615f904f56e261e49cbefc6 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_rv.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/insert_rv.pass.cpp
@@ -54,7 +54,7 @@ void do_insert_rv_test()
     assert(r->second == 3);
 }
 
-int main()
+int main(int, char**)
 {
     do_insert_rv_test<std::multimap<int, MoveOnly>>();
     {
@@ -89,4 +89,6 @@ int main()
         assert(r->first == 3);
         assert(r->second == 3);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/merge.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/merge.pass.cpp
index 449d5d92ddaf558a65ca81b02bcd6699bada1860..78b24323d4476a12b5e395c64920968c8daa2b83 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.modifiers/merge.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.modifiers/merge.pass.cpp
@@ -49,7 +49,7 @@ struct throw_comparator
 };
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         std::multimap<int, int> src{{1, 0}, {3, 0}, {5, 0}};
@@ -146,4 +146,5 @@ int main()
             first.merge(std::move(second));
         }
     }
+    return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.ops/count.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.ops/count.pass.cpp
index 7bdb4d200709db3efe919a9b30550c7289e0b03c..053a771bae3c9a413a7ef087f71bdffd485e47c2 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.ops/count.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.ops/count.pass.cpp
@@ -20,7 +20,7 @@
 #include "private_constructor.hpp"
 #include "is_transparent.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::pair<const int, double> V;
     {
@@ -172,4 +172,6 @@ int main()
     assert(r == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.ops/count0.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.ops/count0.pass.cpp
index f725d16f8b3e624807b259a364ca5da4da1d3135..75f9f222816557e494618bf6626045f7180786fa 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.ops/count0.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.ops/count0.pass.cpp
@@ -25,7 +25,7 @@
 
 #include "is_transparent.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::multimap<int, double, transparent_less> M;
@@ -35,4 +35,6 @@ int main()
     typedef std::multimap<int, double, transparent_less_not_referenceable> M;
     assert(M().count(C2Int{5}) == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.ops/count1.fail.cpp b/libcxx/test/std/containers/associative/multimap/multimap.ops/count1.fail.cpp
index 28842553b5f2fb2255c3869c135022c171865ea9..594a424fad48f4043f371b19c9f9849ac036cf1f 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.ops/count1.fail.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.ops/count1.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     typedef std::multimap<int, double, transparent_less_no_type> M;
 
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.ops/count2.fail.cpp b/libcxx/test/std/containers/associative/multimap/multimap.ops/count2.fail.cpp
index 5f06d32261829b6027f3149197141e41c2b314fa..1f98052b7b2abd2c3c2400bc2276e182955d307c 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.ops/count2.fail.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.ops/count2.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     typedef std::multimap<int, double, transparent_less_private> M;
 
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.ops/count3.fail.cpp b/libcxx/test/std/containers/associative/multimap/multimap.ops/count3.fail.cpp
index 2f3aa4dcbf9ec39d04344d2f5538f38f0b38dc74..3304d9f06400b06e203834c172d9dbb8fb89105e 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.ops/count3.fail.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.ops/count3.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     typedef std::multimap<int, double, transparent_less_not_a_type> M;
 
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.ops/count_transparent.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.ops/count_transparent.pass.cpp
index 0483276f84b64fd6fdfe6a7f6695bb84848ef6ce..e6348cbef2a5f726f69444dcef82140001c77151 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.ops/count_transparent.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.ops/count_transparent.pass.cpp
@@ -40,10 +40,12 @@ struct Comp {
   }
 };
 
-int main() {
+int main(int, char**) {
   std::multimap<std::pair<int, int>, int, Comp> s{
       {{2, 1}, 1}, {{1, 1}, 2}, {{1, 1}, 3}, {{1, 1}, 4}, {{2, 2}, 5}};
 
   auto cnt = s.count(1);
   assert(cnt == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.ops/equal_range.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.ops/equal_range.pass.cpp
index 47380d881caa7823c0f0222eeb27325e839a44dd..3d4997f4844368ba78a7f5e7523e1740c9144e43 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.ops/equal_range.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.ops/equal_range.pass.cpp
@@ -21,7 +21,7 @@
 #include "private_constructor.hpp"
 #include "is_transparent.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::pair<const int, double> V;
     {
@@ -283,4 +283,6 @@ int main()
     assert(r.second == m.end());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.ops/equal_range0.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.ops/equal_range0.pass.cpp
index 48002b38123ca2e3fe2c031f066e51e3fe70545e..c01395f0a412261a5a38d94397799a2786a42d78 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.ops/equal_range0.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.ops/equal_range0.pass.cpp
@@ -25,7 +25,7 @@
 
 #include "is_transparent.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::multimap<int, double, transparent_less> M;
@@ -41,4 +41,6 @@ int main()
     P result = example.equal_range(C2Int{5});
     assert(result.first == result.second);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.ops/equal_range1.fail.cpp b/libcxx/test/std/containers/associative/multimap/multimap.ops/equal_range1.fail.cpp
index ea7941c71f65b5c16dff176d90501168e5c5aa72..b826f018fae84c277c3bf7dfbd12d95a055a0960 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.ops/equal_range1.fail.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.ops/equal_range1.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     typedef std::multimap<int, double, transparent_less_no_type> M;
 
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.ops/equal_range2.fail.cpp b/libcxx/test/std/containers/associative/multimap/multimap.ops/equal_range2.fail.cpp
index a6fc925a807571dc9f17cbb11cf1690a06e108a4..a533a7144e7a11a2659614d3241c42ab28be9656 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.ops/equal_range2.fail.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.ops/equal_range2.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::multimap<int, double, transparent_less_private> M;
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.ops/equal_range3.fail.cpp b/libcxx/test/std/containers/associative/multimap/multimap.ops/equal_range3.fail.cpp
index 8b5e77242df94a68898805ae47a54ae64e582fd9..2a26a5849c924a67663771e105ba1b27a886ddfe 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.ops/equal_range3.fail.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.ops/equal_range3.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::multimap<int, double, transparent_less_not_a_type> M;
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.ops/equal_range_transparent.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.ops/equal_range_transparent.pass.cpp
index 34326a453b1f9594c9ffdf3148c1db2fc1ba68f8..95af97cee52a5b2c66ff1aa2b9ad1cb9d7fc02da 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.ops/equal_range_transparent.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.ops/equal_range_transparent.pass.cpp
@@ -43,7 +43,7 @@ struct Comp {
   }
 };
 
-int main() {
+int main(int, char**) {
   std::multimap<std::pair<int, int>, int, Comp> s{
       {{2, 1}, 1}, {{1, 1}, 2}, {{1, 1}, 3}, {{1, 1}, 4}, {{2, 2}, 5}};
 
@@ -56,4 +56,6 @@ int main() {
   }
 
   assert(nels == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.ops/find.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.ops/find.pass.cpp
index 006f98b9635ad281ffd68876b3ee2ecbec1dae63..e526d9a3270dbf6de9a973a20c083523e618afd8 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.ops/find.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.ops/find.pass.cpp
@@ -21,7 +21,7 @@
 #include "private_constructor.hpp"
 #include "is_transparent.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::pair<const int, double> V;
     {
@@ -219,4 +219,6 @@ int main()
     assert(r == m.end());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.ops/find0.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.ops/find0.pass.cpp
index 2516b16e7e5bba5e33657d46aae1416768d870ca..39a8735bccbb0260b951a2569d29ab592c01724c 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.ops/find0.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.ops/find0.pass.cpp
@@ -25,7 +25,7 @@
 
 #include "is_transparent.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::multimap<int, double, transparent_less> M;
@@ -37,4 +37,6 @@ int main()
     M example;
     assert(example.find(C2Int{5}) == example.end());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.ops/find1.fail.cpp b/libcxx/test/std/containers/associative/multimap/multimap.ops/find1.fail.cpp
index 754df859a8a85f8c59356b59f78cf426fa23c130..a22d1b5a0377139a96de6c8d2a6b2b1951c5acf6 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.ops/find1.fail.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.ops/find1.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::multimap<int, double, transparent_less_no_type> M;
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.ops/find2.fail.cpp b/libcxx/test/std/containers/associative/multimap/multimap.ops/find2.fail.cpp
index 898fdbafbbf22f2bcb38c6bff23830146f912d8c..cf2e4b4987b9f7f680c7a668007db64d0e85fc6c 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.ops/find2.fail.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.ops/find2.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::multimap<int, double, transparent_less_private> M;
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.ops/find3.fail.cpp b/libcxx/test/std/containers/associative/multimap/multimap.ops/find3.fail.cpp
index 68608e8d049286e70613122d51e505792ec0f088..2be4062bb5d033bc2c716cc3bcdb17762284abec 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.ops/find3.fail.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.ops/find3.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::multimap<int, double, transparent_less_not_a_type> M;
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.ops/lower_bound.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.ops/lower_bound.pass.cpp
index c94f99d49407d827d27c028d3650df393b97017c..77550b5186aeefea6a86cace87469eb348b649f4 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.ops/lower_bound.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.ops/lower_bound.pass.cpp
@@ -21,7 +21,7 @@
 #include "private_constructor.hpp"
 #include "is_transparent.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::pair<const int, double> V;
     {
@@ -233,4 +233,6 @@ int main()
     }
 
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.ops/lower_bound0.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.ops/lower_bound0.pass.cpp
index fd604d14ebc2941cd1baf1a735175ce2a58a6ce6..1311c9c5a47bedf26189cdf20c155c6bad59d468 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.ops/lower_bound0.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.ops/lower_bound0.pass.cpp
@@ -25,7 +25,7 @@
 
 #include "is_transparent.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::multimap<int, double, transparent_less> M;
@@ -37,4 +37,6 @@ int main()
     M example;
     assert(example.lower_bound(C2Int{5}) == example.end());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.ops/lower_bound1.fail.cpp b/libcxx/test/std/containers/associative/multimap/multimap.ops/lower_bound1.fail.cpp
index 510421a8abd9485da21eb8b52a19f23371a92836..0279f54bf440aeab0e81bf24ab543a851e1aaafc 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.ops/lower_bound1.fail.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.ops/lower_bound1.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::multimap<int, double, transparent_less_no_type> M;
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.ops/lower_bound2.fail.cpp b/libcxx/test/std/containers/associative/multimap/multimap.ops/lower_bound2.fail.cpp
index afcf3285ad521fe091afac0d9cecbe7ddaa8eadf..2282003f4d44d8bcf7b5b4e046fd2cc9d8a0fc38 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.ops/lower_bound2.fail.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.ops/lower_bound2.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::multimap<int, double, transparent_less_private> M;
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.ops/lower_bound3.fail.cpp b/libcxx/test/std/containers/associative/multimap/multimap.ops/lower_bound3.fail.cpp
index 3c7e276763e2837e2e86e632544f5da553edaaba..f5751647ac645ca8d1589534a60ab33439f34018 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.ops/lower_bound3.fail.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.ops/lower_bound3.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::multimap<int, double, transparent_less_not_a_type> M;
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.ops/upper_bound.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.ops/upper_bound.pass.cpp
index 5a0d7c3ce43030025e71507d7f00f965c5762ac2..762387d800d88ca1a7c554f2ab7b43ec595a3ee2 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.ops/upper_bound.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.ops/upper_bound.pass.cpp
@@ -21,7 +21,7 @@
 #include "private_constructor.hpp"
 #include "is_transparent.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::pair<const int, double> V;
     {
@@ -232,4 +232,6 @@ int main()
     }
 
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.ops/upper_bound0.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.ops/upper_bound0.pass.cpp
index 5f257ece9f9711f1eb07f78b6f7bc51a78ef84bf..28c9ff75a7510ac5c3d8880183ac5c1d1f91e361 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.ops/upper_bound0.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.ops/upper_bound0.pass.cpp
@@ -25,7 +25,7 @@
 
 #include "is_transparent.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::multimap<int, double, transparent_less> M;
@@ -37,4 +37,6 @@ int main()
     M example;
     assert(example.upper_bound(C2Int{5}) == example.end());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.ops/upper_bound1.fail.cpp b/libcxx/test/std/containers/associative/multimap/multimap.ops/upper_bound1.fail.cpp
index 33775d23872c715f9046f7e80ed4188d824f0c81..39ecc3cc4cf69f4d5348a680bb4f39ffe3beb944 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.ops/upper_bound1.fail.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.ops/upper_bound1.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::multimap<int, double, transparent_less_no_type> M;
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.ops/upper_bound2.fail.cpp b/libcxx/test/std/containers/associative/multimap/multimap.ops/upper_bound2.fail.cpp
index c2be3e7ebe5faeb92b48de30ed2654c357f026df..f51a199c1198eb554248746d92de8454efe9b522 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.ops/upper_bound2.fail.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.ops/upper_bound2.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::multimap<int, double, transparent_less_private> M;
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.ops/upper_bound3.fail.cpp b/libcxx/test/std/containers/associative/multimap/multimap.ops/upper_bound3.fail.cpp
index 5c1d2a77bf1907caba3b8330121e540085809832..68d05710048f073305c5c37793f9ed4f0fe5c031 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.ops/upper_bound3.fail.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.ops/upper_bound3.fail.cpp
@@ -28,7 +28,7 @@
 #error "This test requires is C++14 (or later)"
 #else
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::multimap<int, double, transparent_less_not_a_type> M;
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.special/member_swap.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.special/member_swap.pass.cpp
index 09740b3f331485080c93c16447da978b74d3b8f9..fe8399713efe0974e003660ca69858ef623eb5c3 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.special/member_swap.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.special/member_swap.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::pair<const int, double> V;
     {
@@ -172,4 +172,6 @@ int main()
     }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.special/non_member_swap.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.special/non_member_swap.pass.cpp
index b776766dda6c3b96fee9dabd2f4b05dd34510d78..3e75991ee95335a0fd7fc2113e435579586f633d 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.special/non_member_swap.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.special/non_member_swap.pass.cpp
@@ -20,7 +20,7 @@
 #include "../../../test_compare.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::pair<const int, double> V;
     {
@@ -277,4 +277,6 @@ int main()
         assert(m2.get_allocator() == A());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/multimap.special/swap_noexcept.pass.cpp b/libcxx/test/std/containers/associative/multimap/multimap.special/swap_noexcept.pass.cpp
index 7c42ff170d84328bff89cd1d395e4fa5592d77d9..9d5dab06c892f41ef52f68e95e3cd412c230ee7f 100644
--- a/libcxx/test/std/containers/associative/multimap/multimap.special/swap_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/multimap.special/swap_noexcept.pass.cpp
@@ -91,7 +91,7 @@ struct some_alloc3
     typedef std::false_type is_always_equal;
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::pair<const MoveOnly, MoveOnly> V;
     {
@@ -137,4 +137,6 @@ int main()
     }
 #endif // _LIBCPP_VERSION
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/scary.pass.cpp b/libcxx/test/std/containers/associative/multimap/scary.pass.cpp
index 2032bfc9699e24b289427209284fa0c94e32e463..faf839b8ee17fdce32946247b6a646e3338107d6 100644
--- a/libcxx/test/std/containers/associative/multimap/scary.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/scary.pass.cpp
@@ -14,11 +14,13 @@
 
 #include <map>
 
-int main()
+int main(int, char**)
 {
     typedef std::map<int, int> M1;
     typedef std::multimap<int, int> M2;
     M2::iterator i;
     M1::iterator j = i;
     ((void)j);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/size.pass.cpp b/libcxx/test/std/containers/associative/multimap/size.pass.cpp
index b608b99e93ca1d14625436c64d5c4ed5aa576a42..df18f7b58ccadae9b2100df81de3e3b41cc0b052 100644
--- a/libcxx/test/std/containers/associative/multimap/size.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/size.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::multimap<int, double> M;
@@ -55,4 +55,6 @@ int main()
     assert(m.size() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multimap/types.pass.cpp b/libcxx/test/std/containers/associative/multimap/types.pass.cpp
index 7c91ab3bdad5567cbfaa69a287e3b1cf93cd42bc..67723f5cdc4a6b3bc98b2bc58dcf8c3be16e09bf 100644
--- a/libcxx/test/std/containers/associative/multimap/types.pass.cpp
+++ b/libcxx/test/std/containers/associative/multimap/types.pass.cpp
@@ -33,7 +33,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::multimap<int, double> C;
@@ -66,4 +66,6 @@ int main()
     static_assert((std::is_same<C::difference_type, std::ptrdiff_t>::value), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/allocator_mismatch.fail.cpp b/libcxx/test/std/containers/associative/multiset/allocator_mismatch.fail.cpp
index ffa0e964074136150dd2e762a584e2644f480550..86e1b307a3de74e1c379f5df57e7d31e0131f959 100644
--- a/libcxx/test/std/containers/associative/multiset/allocator_mismatch.fail.cpp
+++ b/libcxx/test/std/containers/associative/multiset/allocator_mismatch.fail.cpp
@@ -11,7 +11,9 @@
 
 #include <set>
 
-int main()
+int main(int, char**)
 {
     std::multiset<int, std::less<int>, std::allocator<long> > ms;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/clear.pass.cpp b/libcxx/test/std/containers/associative/multiset/clear.pass.cpp
index b5ad9e4f30443fe3dbbdd1eedc111dbee62070e9..93f9fef2caa0ad23e9d72dae361fdd7908cc0a1c 100644
--- a/libcxx/test/std/containers/associative/multiset/clear.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/clear.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::multiset<int> M;
@@ -62,4 +62,6 @@ int main()
         assert(m.size() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/count.pass.cpp b/libcxx/test/std/containers/associative/multiset/count.pass.cpp
index 61d64adb6aea68eb2d6bee6d55fbc5dd78fc587a..3ac6f94230439f331c059fc933da4624e199e391 100644
--- a/libcxx/test/std/containers/associative/multiset/count.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/count.pass.cpp
@@ -19,7 +19,7 @@
 #include "min_allocator.h"
 #include "private_constructor.hpp"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int V;
@@ -157,4 +157,6 @@ int main()
     assert(r == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/count_transparent.pass.cpp b/libcxx/test/std/containers/associative/multiset/count_transparent.pass.cpp
index e26744a75f2299718eef2e1e82155a3909e37fe0..1239286f76c7d80453432179ffc774e1e55536bd 100644
--- a/libcxx/test/std/containers/associative/multiset/count_transparent.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/count_transparent.pass.cpp
@@ -42,9 +42,11 @@ struct Comp {
   }
 };
 
-int main() {
+int main(int, char**) {
   std::multiset<std::pair<int, int>, Comp> s{{2, 1}, {1, 1}, {1, 1}, {1, 1}, {2, 2}};
 
   auto cnt = s.count(1);
   assert(cnt == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/emplace.pass.cpp b/libcxx/test/std/containers/associative/multiset/emplace.pass.cpp
index 8e7b6946c350697619bf03f78c6af41b65bcad7e..1cabd12fce047518a8e03d7b3939279a27932a64 100644
--- a/libcxx/test/std/containers/associative/multiset/emplace.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/emplace.pass.cpp
@@ -22,7 +22,7 @@
 #include "DefaultOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::multiset<DefaultOnly> M;
@@ -77,4 +77,6 @@ int main()
         assert(m.size() == 1);
         assert(*r == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/emplace_hint.pass.cpp b/libcxx/test/std/containers/associative/multiset/emplace_hint.pass.cpp
index d8723d8d91623e49dad940074cd94633b984987c..17db3b4b366ec94ddd0470dc6ac9c3330bd44a80 100644
--- a/libcxx/test/std/containers/associative/multiset/emplace_hint.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/emplace_hint.pass.cpp
@@ -22,7 +22,7 @@
 #include "DefaultOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::multiset<DefaultOnly> M;
@@ -77,4 +77,6 @@ int main()
         assert(m.size() == 1);
         assert(*r == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/empty.fail.cpp b/libcxx/test/std/containers/associative/multiset/empty.fail.cpp
index 29c31a0899a1864babba301b543a295b26c35449..4467b487089b0d6cc1f6b37c4a3babf3dbbb3e5d 100644
--- a/libcxx/test/std/containers/associative/multiset/empty.fail.cpp
+++ b/libcxx/test/std/containers/associative/multiset/empty.fail.cpp
@@ -20,8 +20,10 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     std::multiset<int> c;
     c.empty();  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/empty.pass.cpp b/libcxx/test/std/containers/associative/multiset/empty.pass.cpp
index f0591d8e3d9825a96d6e4c918fc6d801560305dc..2ca20491fca474cfb76eb3616a62fc124170feaa 100644
--- a/libcxx/test/std/containers/associative/multiset/empty.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/empty.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::multiset<int> M;
@@ -39,4 +39,6 @@ int main()
     assert(m.empty());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/equal_range.pass.cpp b/libcxx/test/std/containers/associative/multiset/equal_range.pass.cpp
index 740ecc7f290a0cb37cd8c2884d3bead5bdda55be..44c6c17ecce6dd8130982a578591cb01b4d2821c 100644
--- a/libcxx/test/std/containers/associative/multiset/equal_range.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/equal_range.pass.cpp
@@ -20,7 +20,7 @@
 #include "min_allocator.h"
 #include "private_constructor.hpp"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int V;
@@ -260,4 +260,6 @@ int main()
     assert(r.second == next(m.begin(), 9));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/equal_range_transparent.pass.cpp b/libcxx/test/std/containers/associative/multiset/equal_range_transparent.pass.cpp
index 075aab1a365ecb1f0054b77fa486a9b3455bc910..d052cf169b713fc35ca57af3753d1aef3069cb1a 100644
--- a/libcxx/test/std/containers/associative/multiset/equal_range_transparent.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/equal_range_transparent.pass.cpp
@@ -44,7 +44,7 @@ struct Comp {
   }
 };
 
-int main() {
+int main(int, char**) {
   std::multiset<std::pair<int, int>, Comp> s{{2, 1}, {1, 1}, {1, 1}, {1, 1}, {2, 2}};
 
   auto er = s.equal_range(1);
@@ -56,4 +56,6 @@ int main() {
   }
 
   assert(nels == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/erase_iter.pass.cpp b/libcxx/test/std/containers/associative/multiset/erase_iter.pass.cpp
index 506a0a7c2f90ede62df1f7f78cfd28962a4b9dae..bcedbf338a668609aff20c78be8ae2a885d8bbcc 100644
--- a/libcxx/test/std/containers/associative/multiset/erase_iter.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/erase_iter.pass.cpp
@@ -25,7 +25,7 @@ struct TemplateConstructor
 
 bool operator<(const TemplateConstructor&, const TemplateConstructor&) { return false; }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::multiset<int> M;
@@ -199,4 +199,6 @@ int main()
             c.erase(it);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/erase_iter_iter.pass.cpp b/libcxx/test/std/containers/associative/multiset/erase_iter_iter.pass.cpp
index b1e2d143b7269b4e6e5483cbcfdb38e9f5f21f96..03c725285945490bc69f98e652e6d1bb75fb5e87 100644
--- a/libcxx/test/std/containers/associative/multiset/erase_iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/erase_iter_iter.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::multiset<int> M;
@@ -137,4 +137,6 @@ int main()
         assert(i == m.end());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/erase_key.pass.cpp b/libcxx/test/std/containers/associative/multiset/erase_key.pass.cpp
index d2c3d17db329391c48330a9bf5d569c8f33fb4d4..4b1db05296091bf2678f1743ddd1f32c4ff5bf8e 100644
--- a/libcxx/test/std/containers/associative/multiset/erase_key.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/erase_key.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::multiset<int> M;
@@ -125,4 +125,6 @@ int main()
         assert(i == 3);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/extract_iterator.pass.cpp b/libcxx/test/std/containers/associative/multiset/extract_iterator.pass.cpp
index f162081902ff1c4ba2ac53ddeeda0dfbfdba859f..ef2a64eded056962a8b319040836f93605a168de 100644
--- a/libcxx/test/std/containers/associative/multiset/extract_iterator.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/extract_iterator.pass.cpp
@@ -36,7 +36,7 @@ void test(Container& c)
     assert(c.size() == 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
         using set_type = std::multiset<int>;
@@ -56,4 +56,6 @@ int main()
         min_alloc_set m = {1, 2, 3, 4, 5, 6};
         test(m);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/extract_key.pass.cpp b/libcxx/test/std/containers/associative/multiset/extract_key.pass.cpp
index 7fc0459cae09c7cb7810051cb88d00f7afd4fbfb..d95667def3a7d9d0e0c6aa7a83d2e04fc267706d 100644
--- a/libcxx/test/std/containers/associative/multiset/extract_key.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/extract_key.pass.cpp
@@ -43,7 +43,7 @@ void test(Container& c, KeyTypeIter first, KeyTypeIter last)
     }
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::multiset<int> m = {1, 2, 3, 4, 5, 6};
@@ -67,4 +67,6 @@ int main()
         int keys[] = {1, 2, 3, 4, 5, 6};
         test(m, std::begin(keys), std::end(keys));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/find.pass.cpp b/libcxx/test/std/containers/associative/multiset/find.pass.cpp
index 44d8d051cfcd225bc9f1dc726e36806389a544d7..7a6584b2bb1a019b4a7f4ae071381ab67ae0e2a1 100644
--- a/libcxx/test/std/containers/associative/multiset/find.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/find.pass.cpp
@@ -20,7 +20,7 @@
 #include "min_allocator.h"
 #include "private_constructor.hpp"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int V;
@@ -237,4 +237,6 @@ int main()
     assert(r == next(m.begin(), 8));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/incomplete_type.pass.cpp b/libcxx/test/std/containers/associative/multiset/incomplete_type.pass.cpp
index 71166b2ecd37f19d4ef45b0d3d9d783e8c6e0b89..a118a6230ebcff9c5b1c794ce8263b3047e1bda5 100644
--- a/libcxx/test/std/containers/associative/multiset/incomplete_type.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/incomplete_type.pass.cpp
@@ -23,6 +23,8 @@ struct A {
 
 inline bool operator==(A const& L, A const& R) { return &L == &R; }
 inline bool operator<(A const& L, A const& R)  { return L.data < R.data; }
-int main() {
+int main(int, char**) {
     A a;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/insert_cv.pass.cpp b/libcxx/test/std/containers/associative/multiset/insert_cv.pass.cpp
index 21fec2cd95b8789457d4ccf194847a4d00e0b2a1..856d54da0d4beb65e9bfd9f898d8bf6bff20923f 100644
--- a/libcxx/test/std/containers/associative/multiset/insert_cv.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/insert_cv.pass.cpp
@@ -48,7 +48,7 @@ void do_insert_cv_test()
     assert(*r == 3);
 }
 
-int main()
+int main(int, char**)
 {
     do_insert_cv_test<std::multiset<int> >();
 #if TEST_STD_VER >= 11
@@ -57,4 +57,6 @@ int main()
         do_insert_cv_test<M>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/insert_emplace_allocator_requirements.pass.cpp b/libcxx/test/std/containers/associative/multiset/insert_emplace_allocator_requirements.pass.cpp
index 6b6c22f28513b4de5d4e4804ae63f9bfae49366c..083dea73917a1d4215d9f9e4ecb01aff9a259fc9 100644
--- a/libcxx/test/std/containers/associative/multiset/insert_emplace_allocator_requirements.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/insert_emplace_allocator_requirements.pass.cpp
@@ -19,8 +19,10 @@
 #include "container_test_types.h"
 #include "../../set_allocator_requirement_test_templates.h"
 
-int main()
+int main(int, char**)
 {
   testMultisetInsert<TCT::multiset<> >();
   testMultisetEmplace<TCT::multiset<> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/insert_initializer_list.pass.cpp b/libcxx/test/std/containers/associative/multiset/insert_initializer_list.pass.cpp
index 29a746696b6a450489f3e2c9848e7b90366886c1..7f7a00c15f838b84b65b3e0fb2665d1ac94f1ca9 100644
--- a/libcxx/test/std/containers/associative/multiset/insert_initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/insert_initializer_list.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::multiset<int> C;
@@ -56,4 +56,6 @@ int main()
     assert(*++i == V(8));
     assert(*++i == V(10));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/insert_iter_cv.pass.cpp b/libcxx/test/std/containers/associative/multiset/insert_iter_cv.pass.cpp
index b0da5f4f2d76cf548c2a4a3c0f7638124aa8751c..e29e7b484eb5189dc97497ef7ff32e3af3ddb4b0 100644
--- a/libcxx/test/std/containers/associative/multiset/insert_iter_cv.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/insert_iter_cv.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::multiset<int> M;
@@ -69,4 +69,6 @@ int main()
         assert(*r == 3);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/insert_iter_iter.pass.cpp b/libcxx/test/std/containers/associative/multiset/insert_iter_iter.pass.cpp
index 07b8000d94178de49520e56f329c19f64f85f574..242b9d7f6cc9882cda676cd4d6b08f3d8dc5b333 100644
--- a/libcxx/test/std/containers/associative/multiset/insert_iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/insert_iter_iter.pass.cpp
@@ -19,7 +19,7 @@
 #include "test_iterators.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::multiset<int> M;
@@ -81,4 +81,6 @@ int main()
         assert(*next(m.begin(), 8) == 3);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/insert_iter_rv.pass.cpp b/libcxx/test/std/containers/associative/multiset/insert_iter_rv.pass.cpp
index 3dea1f8a222f4aeb88ddf999adb3688dc63d85b7..e905c5c407276d249db412a9f7f8e7299b34b8e4 100644
--- a/libcxx/test/std/containers/associative/multiset/insert_iter_rv.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/insert_iter_rv.pass.cpp
@@ -20,7 +20,7 @@
 #include "MoveOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::multiset<MoveOnly> M;
@@ -70,4 +70,6 @@ int main()
         assert(m.size() == 4);
         assert(*r == 3);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/insert_node_type.pass.cpp b/libcxx/test/std/containers/associative/multiset/insert_node_type.pass.cpp
index b8aad6c8cc6ce2eec67956fcc41b01dbe996632f..7cf2cebfb58146ee11810b50042b092a27e030df 100644
--- a/libcxx/test/std/containers/associative/multiset/insert_node_type.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/insert_node_type.pass.cpp
@@ -67,10 +67,12 @@ void test(Container& c)
     }
 }
 
-int main()
+int main(int, char**)
 {
     std::multiset<int> m;
     test(m);
     std::multiset<int, std::less<int>, min_allocator<int>> m2;
     test(m2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/insert_node_type_hint.pass.cpp b/libcxx/test/std/containers/associative/multiset/insert_node_type_hint.pass.cpp
index 3e5b40b96c582707856177506f13d473e1cb7b39..d4d6871fb1374befb5313d34e7659e64ed1c237f 100644
--- a/libcxx/test/std/containers/associative/multiset/insert_node_type_hint.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/insert_node_type_hint.pass.cpp
@@ -49,10 +49,12 @@ void test(Container& c)
     }
 }
 
-int main()
+int main(int, char**)
 {
     std::multiset<int> m;
     test(m);
     std::multiset<int, std::less<int>, min_allocator<int>> m2;
     test(m2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/insert_rv.pass.cpp b/libcxx/test/std/containers/associative/multiset/insert_rv.pass.cpp
index 9d50c617dc92b3e40d2b2c55656733ac08da10f8..3f73a2813b0933190a29f82a10d48375239fe945 100644
--- a/libcxx/test/std/containers/associative/multiset/insert_rv.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/insert_rv.pass.cpp
@@ -20,7 +20,7 @@
 #include "MoveOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::multiset<MoveOnly> M;
@@ -70,4 +70,6 @@ int main()
         assert(m.size() == 4);
         assert(*r == 3);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/iterator.pass.cpp b/libcxx/test/std/containers/associative/multiset/iterator.pass.cpp
index bda2c7faa8234591c433b8ba58d246695aa8b568..4ab1d79a0491f7a2c8f3421c335ca7de8f72531b 100644
--- a/libcxx/test/std/containers/associative/multiset/iterator.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/iterator.pass.cpp
@@ -32,7 +32,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int V;
@@ -213,4 +213,6 @@ int main()
         assert (!(cii != ii1 ));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/lower_bound.pass.cpp b/libcxx/test/std/containers/associative/multiset/lower_bound.pass.cpp
index dd9fdf70c7a1388a3ce2ef23751505de23a603ba..6d31f04c8eeffc38266fe2c797de290d2b2a43eb 100644
--- a/libcxx/test/std/containers/associative/multiset/lower_bound.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/lower_bound.pass.cpp
@@ -20,7 +20,7 @@
 #include "min_allocator.h"
 #include "private_constructor.hpp"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int V;
@@ -220,4 +220,6 @@ int main()
     assert(r == next(m.begin(), 9));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/max_size.pass.cpp b/libcxx/test/std/containers/associative/multiset/max_size.pass.cpp
index 64baa6cb04657f032588a0164dc95fe36ce14551..5986df295545a780904d425d118ade154315b4a4 100644
--- a/libcxx/test/std/containers/associative/multiset/max_size.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/max_size.pass.cpp
@@ -20,7 +20,7 @@
 #include "test_allocator.h"
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
       typedef limited_allocator<int, 10> A;
@@ -46,4 +46,6 @@ int main()
       assert(c.max_size() <= max_dist);
       assert(c.max_size() <= alloc_max_size(c.get_allocator()));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/merge.pass.cpp b/libcxx/test/std/containers/associative/multiset/merge.pass.cpp
index 9d566484c33bac971ef0c4b306d701b329574054..e7e05b155f4d5e76942c314e31124bef662af81e 100644
--- a/libcxx/test/std/containers/associative/multiset/merge.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/merge.pass.cpp
@@ -49,7 +49,7 @@ struct throw_comparator
 };
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         std::multiset<int> src{1, 3, 5};
@@ -145,4 +145,5 @@ int main()
             first.merge(std::move(second));
         }
     }
+    return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/multiset.cons/alloc.pass.cpp b/libcxx/test/std/containers/associative/multiset/multiset.cons/alloc.pass.cpp
index 4debe7b4278ef6d367ee26fa1e74782ea18be32b..9ceac884b64dc9df955e4455284c5242556837b3 100644
--- a/libcxx/test/std/containers/associative/multiset/multiset.cons/alloc.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/multiset.cons/alloc.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::less<int> C;
     typedef test_allocator<int> A;
@@ -25,4 +25,6 @@ int main()
     assert(m.empty());
     assert(m.begin() == m.end());
     assert(m.get_allocator() == A(5));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/multiset.cons/assign_initializer_list.pass.cpp b/libcxx/test/std/containers/associative/multiset/multiset.cons/assign_initializer_list.pass.cpp
index f325fe919d4e1300fb2bfcbc3b6a75d4c738b290..c84b042930ae38cb58b6953a611bbd8c3c148f79 100644
--- a/libcxx/test/std/containers/associative/multiset/multiset.cons/assign_initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/multiset.cons/assign_initializer_list.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::multiset<int> C;
@@ -51,4 +51,6 @@ int main()
     assert(*++i == V(5));
     assert(*++i == V(6));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/multiset.cons/compare.pass.cpp b/libcxx/test/std/containers/associative/multiset/multiset.cons/compare.pass.cpp
index b628d50ff86dc3c2ba49416d37a120056b3c71b2..d35de106f8531684d22f8366c5a447571c8f24a8 100644
--- a/libcxx/test/std/containers/associative/multiset/multiset.cons/compare.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/multiset.cons/compare.pass.cpp
@@ -21,7 +21,7 @@
 
 #include "../../../test_compare.h"
 
-int main()
+int main(int, char**)
 {
     typedef test_compare<std::less<int> > C;
     const std::multiset<int, C> m(C(3));
@@ -29,4 +29,6 @@ int main()
     assert(m.begin() == m.end());
     assert(m.key_comp() == C(3));
     assert(m.value_comp() == C(3));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/multiset.cons/compare_alloc.pass.cpp b/libcxx/test/std/containers/associative/multiset/multiset.cons/compare_alloc.pass.cpp
index e06c21719b36fcab3d37fee68e7c6312d2205089..f044b2790b9f5b16ae8167d11d201a93dd26961b 100644
--- a/libcxx/test/std/containers/associative/multiset/multiset.cons/compare_alloc.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/multiset.cons/compare_alloc.pass.cpp
@@ -18,7 +18,7 @@
 #include "../../../test_compare.h"
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     typedef test_compare<std::less<int> > C;
     typedef test_allocator<int> A;
@@ -27,4 +27,6 @@ int main()
     assert(m.begin() == m.end());
     assert(m.key_comp() == C(4));
     assert(m.get_allocator() == A(5));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/multiset.cons/compare_copy_constructible.fail.cpp b/libcxx/test/std/containers/associative/multiset/multiset.cons/compare_copy_constructible.fail.cpp
index 09c2ac0936cd2a86beb8c42bbbfed3b0990e0b20..ae987c64c85bae49f02ef5b1110b3f34ccf99658 100644
--- a/libcxx/test/std/containers/associative/multiset/multiset.cons/compare_copy_constructible.fail.cpp
+++ b/libcxx/test/std/containers/associative/multiset/multiset.cons/compare_copy_constructible.fail.cpp
@@ -23,6 +23,8 @@ private:
     };
 
 
-int main() {
+int main(int, char**) {
     std::multiset<int, Comp<int> > m;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/multiset.cons/copy.pass.cpp b/libcxx/test/std/containers/associative/multiset/multiset.cons/copy.pass.cpp
index a055b15fce1bc675d2fc85a00961d122c81495ec..ac196b5ae33b45fc997f25d47e75df14c765e72d 100644
--- a/libcxx/test/std/containers/associative/multiset/multiset.cons/copy.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/multiset.cons/copy.pass.cpp
@@ -19,7 +19,7 @@
 #include "../../../test_compare.h"
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int V;
@@ -115,4 +115,6 @@ int main()
         assert(*next(mo.begin(), 8) == 3);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/multiset.cons/copy_alloc.pass.cpp b/libcxx/test/std/containers/associative/multiset/multiset.cons/copy_alloc.pass.cpp
index 4466438ca1edd8fa7f5b924817e5c11c1e249ae4..25e6d6efb2dfadaf58223f32fb9c1a7c3a5ad701 100644
--- a/libcxx/test/std/containers/associative/multiset/multiset.cons/copy_alloc.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/multiset.cons/copy_alloc.pass.cpp
@@ -18,7 +18,7 @@
 #include "../../../test_compare.h"
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     typedef int V;
     V ar[] =
@@ -64,4 +64,6 @@ int main()
     assert(*next(mo.begin(), 6) == 3);
     assert(*next(mo.begin(), 7) == 3);
     assert(*next(mo.begin(), 8) == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/multiset.cons/copy_assign.pass.cpp b/libcxx/test/std/containers/associative/multiset/multiset.cons/copy_assign.pass.cpp
index 0efa8bec69a95b95e8cc9c754260d0b156d2cd6a..7992c7cae95bdfc1e62b42dd35e50548d8413a89 100644
--- a/libcxx/test/std/containers/associative/multiset/multiset.cons/copy_assign.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/multiset.cons/copy_assign.pass.cpp
@@ -18,7 +18,7 @@
 #include "../../../test_compare.h"
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int V;
@@ -134,4 +134,6 @@ int main()
         assert(*next(mo.begin(), 7) == 3);
         assert(*next(mo.begin(), 8) == 3);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/multiset.cons/default.pass.cpp b/libcxx/test/std/containers/associative/multiset/multiset.cons/default.pass.cpp
index a84bc6d10e24cb8661c10340e32a7f7bcd98d01e..88c5244f8f9e9bceae67255175d4aef83f1c0229 100644
--- a/libcxx/test/std/containers/associative/multiset/multiset.cons/default.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/multiset.cons/default.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::multiset<int> m;
@@ -50,4 +50,6 @@ int main()
     assert(m.begin() == m.end());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/multiset.cons/default_noexcept.pass.cpp b/libcxx/test/std/containers/associative/multiset/multiset.cons/default_noexcept.pass.cpp
index 747e948ed8910fa5edc3e7e5b05cf3f59b73551d..7fa25ac478627dc0cd9d3c7cabfd0a8baec52005 100644
--- a/libcxx/test/std/containers/associative/multiset/multiset.cons/default_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/multiset.cons/default_noexcept.pass.cpp
@@ -33,7 +33,7 @@ struct some_comp
     bool operator()(const T&, const T&) const { return false; }
 };
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -53,4 +53,6 @@ int main()
         typedef std::multiset<MoveOnly, some_comp<MoveOnly>> C;
         static_assert(!std::is_nothrow_default_constructible<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/multiset.cons/dtor_noexcept.pass.cpp b/libcxx/test/std/containers/associative/multiset/multiset.cons/dtor_noexcept.pass.cpp
index e268282651fbf147dc071bcec1e1834196a6f720..8a18a2977de8e3f91ff8fa9671e23caf2f6d5c05 100644
--- a/libcxx/test/std/containers/associative/multiset/multiset.cons/dtor_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/multiset.cons/dtor_noexcept.pass.cpp
@@ -27,7 +27,7 @@ struct some_comp
     bool operator()(const T&, const T&) const { return false; }
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::multiset<MoveOnly> C;
@@ -47,4 +47,6 @@ int main()
         static_assert(!std::is_nothrow_destructible<C>::value, "");
     }
 #endif // _LIBCPP_VERSION
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/multiset.cons/initializer_list.pass.cpp b/libcxx/test/std/containers/associative/multiset/multiset.cons/initializer_list.pass.cpp
index c0a682e91a13f368e85ffc58d1933f8a1f143e95..68a74e80cdc7f8209b919e6cae845370e00e931b 100644
--- a/libcxx/test/std/containers/associative/multiset/multiset.cons/initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/multiset.cons/initializer_list.pass.cpp
@@ -20,7 +20,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::multiset<int> C;
@@ -66,4 +66,6 @@ int main()
     assert(*++i == V(6));
     assert(m.get_allocator() == a);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/multiset.cons/initializer_list_compare.pass.cpp b/libcxx/test/std/containers/associative/multiset/multiset.cons/initializer_list_compare.pass.cpp
index 719476c7d174aed2bc302020003d2a7222d86c4f..cf4c11dcfb622ce569166ae89ed5003363ea73a1 100644
--- a/libcxx/test/std/containers/associative/multiset/multiset.cons/initializer_list_compare.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/multiset.cons/initializer_list_compare.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include "../../../test_compare.h"
 
-int main()
+int main(int, char**)
 {
     typedef test_compare<std::less<int> > Cmp;
     typedef std::multiset<int, Cmp> C;
@@ -34,4 +34,6 @@ int main()
     assert(*++i == V(5));
     assert(*++i == V(6));
     assert(m.key_comp() == Cmp(10));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/multiset.cons/initializer_list_compare_alloc.pass.cpp b/libcxx/test/std/containers/associative/multiset/multiset.cons/initializer_list_compare_alloc.pass.cpp
index 61a1f3ca0ffcf9f9fedc57973e9b3cd3a1769a27..5f26864cd2130ca721517678b368ded6f1ab38f5 100644
--- a/libcxx/test/std/containers/associative/multiset/multiset.cons/initializer_list_compare_alloc.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/multiset.cons/initializer_list_compare_alloc.pass.cpp
@@ -19,7 +19,7 @@
 #include "../../../test_compare.h"
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     typedef test_compare<std::less<int> > Cmp;
     typedef test_allocator<int> A;
@@ -37,4 +37,6 @@ int main()
     assert(*++i == V(6));
     assert(m.key_comp() == Cmp(10));
     assert(m.get_allocator() == A(4));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/multiset.cons/iter_iter.pass.cpp b/libcxx/test/std/containers/associative/multiset/multiset.cons/iter_iter.pass.cpp
index a1806ecf9c321109d293a3a14f7443621ea8812b..9d521c279055e9d5ca8c4b1e8e3e2d75e258465b 100644
--- a/libcxx/test/std/containers/associative/multiset/multiset.cons/iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/multiset.cons/iter_iter.pass.cpp
@@ -19,7 +19,7 @@
 #include "test_iterators.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int V;
@@ -79,4 +79,6 @@ int main()
     assert(*next(m.begin(), 8) == 3);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/multiset.cons/iter_iter_alloc.pass.cpp b/libcxx/test/std/containers/associative/multiset/multiset.cons/iter_iter_alloc.pass.cpp
index 3a37ac014eadf1c6ad911a210eea90f748e13ce8..82d9f4aea1c2dfccc0175019fcf7bcb5dd8d5d34 100644
--- a/libcxx/test/std/containers/associative/multiset/multiset.cons/iter_iter_alloc.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/multiset.cons/iter_iter_alloc.pass.cpp
@@ -22,7 +22,7 @@
 #include "../../../test_compare.h"
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int V;
@@ -91,4 +91,6 @@ int main()
     assert(m.get_allocator() == a);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/multiset.cons/iter_iter_comp.pass.cpp b/libcxx/test/std/containers/associative/multiset/multiset.cons/iter_iter_comp.pass.cpp
index 77f6b10c4b56e8e62e18c892ec29ac39528869f5..25b4364c182a9e4b3e5d46423db163d65fcff562 100644
--- a/libcxx/test/std/containers/associative/multiset/multiset.cons/iter_iter_comp.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/multiset.cons/iter_iter_comp.pass.cpp
@@ -19,7 +19,7 @@
 #include "test_iterators.h"
 #include "../../../test_compare.h"
 
-int main()
+int main(int, char**)
 {
     typedef int V;
     V ar[] =
@@ -49,4 +49,6 @@ int main()
     assert(*next(m.begin(), 6) == 3);
     assert(*next(m.begin(), 7) == 3);
     assert(*next(m.begin(), 8) == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/multiset.cons/move.pass.cpp b/libcxx/test/std/containers/associative/multiset/multiset.cons/move.pass.cpp
index 8d43c098ef0f66e82107de8614d209a76d1aacef..0d6cc72a66eb097edbfcf488637a785fc8996ac8 100644
--- a/libcxx/test/std/containers/associative/multiset/multiset.cons/move.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/multiset.cons/move.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int V;
@@ -113,4 +113,6 @@ int main()
         assert(mo.size() == 0);
         assert(distance(mo.begin(), mo.end()) == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/multiset.cons/move_alloc.pass.cpp b/libcxx/test/std/containers/associative/multiset/multiset.cons/move_alloc.pass.cpp
index c91a97b490f95a8f416be40b6ba50a7c6f793b47..1abe5b928b5652208b244e43d86ce00789236be3 100644
--- a/libcxx/test/std/containers/associative/multiset/multiset.cons/move_alloc.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/multiset.cons/move_alloc.pass.cpp
@@ -23,7 +23,7 @@
 #include "test_allocator.h"
 #include "Counter.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef MoveOnly V;
@@ -184,4 +184,6 @@ int main()
         }
         assert(Counter_base::gConstructed == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/multiset.cons/move_assign.pass.cpp b/libcxx/test/std/containers/associative/multiset/multiset.cons/move_assign.pass.cpp
index 263e48b46fc4dcad3d5fafea2c41166fae9f00d6..6f584f22cf8afc8baa554a31762bf7a5e6fdc5fc 100644
--- a/libcxx/test/std/containers/associative/multiset/multiset.cons/move_assign.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/multiset.cons/move_assign.pass.cpp
@@ -22,7 +22,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef MoveOnly V;
@@ -180,4 +180,6 @@ int main()
         assert(m3.key_comp() == C(5));
         assert(m1.empty());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/multiset.cons/move_assign_noexcept.pass.cpp b/libcxx/test/std/containers/associative/multiset/multiset.cons/move_assign_noexcept.pass.cpp
index aa164edf0c19423716163f03a491904be02e2921..026fc1ba7f1448daad8fec52f525614f680f0845 100644
--- a/libcxx/test/std/containers/associative/multiset/multiset.cons/move_assign_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/multiset.cons/move_assign_noexcept.pass.cpp
@@ -33,7 +33,7 @@ struct some_comp
     bool operator()(const T&, const T&) const { return false; }
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::multiset<MoveOnly> C;
@@ -53,4 +53,6 @@ int main()
         typedef std::multiset<MoveOnly, some_comp<MoveOnly>> C;
         static_assert(!std::is_nothrow_move_assignable<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/multiset.cons/move_noexcept.pass.cpp b/libcxx/test/std/containers/associative/multiset/multiset.cons/move_noexcept.pass.cpp
index 41fd86269bcc1dd8968cf5684eead82cc450b1e7..88bbb59a43d4b328b8221684732d376d25251bbc 100644
--- a/libcxx/test/std/containers/associative/multiset/multiset.cons/move_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/multiset.cons/move_noexcept.pass.cpp
@@ -31,7 +31,7 @@ struct some_comp
     bool operator()(const T&, const T&) const { return false; }
 };
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -51,4 +51,6 @@ int main()
         typedef std::multiset<MoveOnly, some_comp<MoveOnly>> C;
         static_assert(!std::is_nothrow_move_constructible<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/multiset.erasure/erase_if.pass.cpp b/libcxx/test/std/containers/associative/multiset/multiset.erasure/erase_if.pass.cpp
index 19a0d131f8715930a0c92c7ceea7f65a635f366c..84d665cb151138c3079597cc146375a0ed54c4e1 100644
--- a/libcxx/test/std/containers/associative/multiset/multiset.erasure/erase_if.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/multiset.erasure/erase_if.pass.cpp
@@ -66,7 +66,7 @@ void test()
     test0(S({1,2,3}), False, S({1,2,3}));
 }
 
-int main()
+int main(int, char**)
 {
     test<std::multiset<int>>();
     test<std::multiset<int, std::less<int>, min_allocator<int>>> ();
@@ -74,4 +74,6 @@ int main()
 
     test<std::multiset<long>>();
     test<std::multiset<double>>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/multiset.special/member_swap.pass.cpp b/libcxx/test/std/containers/associative/multiset/multiset.special/member_swap.pass.cpp
index be113250225c69f4c9b5501aca53b7cd2f82c82c..9ac0f1709e956724ca6796a483d49e37fd3a6880 100644
--- a/libcxx/test/std/containers/associative/multiset/multiset.special/member_swap.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/multiset.special/member_swap.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int V;
@@ -173,4 +173,6 @@ int main()
     }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/multiset.special/non_member_swap.pass.cpp b/libcxx/test/std/containers/associative/multiset/multiset.special/non_member_swap.pass.cpp
index 9b6d021f5bc868f4a9ebf8a6c90cf570f071ee65..a3bbf551d3d4df2a69f795123b48f8907e224800 100644
--- a/libcxx/test/std/containers/associative/multiset/multiset.special/non_member_swap.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/multiset.special/non_member_swap.pass.cpp
@@ -17,7 +17,7 @@
 #include "test_allocator.h"
 #include "../../../test_compare.h"
 
-int main()
+int main(int, char**)
 {
     typedef int V;
     {
@@ -163,4 +163,6 @@ int main()
         assert(m2.key_comp() == C(1));
         assert(m2.get_allocator() == A(1));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/multiset.special/swap_noexcept.pass.cpp b/libcxx/test/std/containers/associative/multiset/multiset.special/swap_noexcept.pass.cpp
index 367e6e1c9421d6e7fa3f903cf73ca68a62a87831..47a0d411f938375dd178c7ba23d8a581b9bf2b80 100644
--- a/libcxx/test/std/containers/associative/multiset/multiset.special/swap_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/multiset.special/swap_noexcept.pass.cpp
@@ -91,7 +91,7 @@ struct some_alloc3
     typedef std::false_type is_always_equal;
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::multiset<MoveOnly> C;
@@ -136,4 +136,6 @@ int main()
     }
 #endif // _LIBCPP_VERSION
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/scary.pass.cpp b/libcxx/test/std/containers/associative/multiset/scary.pass.cpp
index 329f9f18fd1936275f26bc7532bb2a08eba12129..5065ab96eaaac0f1a981b682737a43d3bc0b673f 100644
--- a/libcxx/test/std/containers/associative/multiset/scary.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/scary.pass.cpp
@@ -14,11 +14,13 @@
 
 #include <set>
 
-int main()
+int main(int, char**)
 {
     typedef std::set<int> M1;
     typedef std::multiset<int> M2;
     M2::iterator i;
     M1::iterator j = i;
     ((void)j);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/size.pass.cpp b/libcxx/test/std/containers/associative/multiset/size.pass.cpp
index ccb3f0f7a7d46460e2cfa72d00ef9e2c1ebafd14..bb5616e9a6218899946c3c86b524dc36cb502437 100644
--- a/libcxx/test/std/containers/associative/multiset/size.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/size.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::multiset<int> M;
@@ -55,4 +55,6 @@ int main()
     assert(m.size() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/types.pass.cpp b/libcxx/test/std/containers/associative/multiset/types.pass.cpp
index 3ee2fc57087bcc54bab2f43c7763accdb998a7c9..96e8ec4f0b1d266c86e667f40166021471567dcc 100644
--- a/libcxx/test/std/containers/associative/multiset/types.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/types.pass.cpp
@@ -33,7 +33,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::multiset<int> C;
@@ -66,4 +66,6 @@ int main()
     static_assert((std::is_same<C::difference_type, std::ptrdiff_t>::value), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/multiset/upper_bound.pass.cpp b/libcxx/test/std/containers/associative/multiset/upper_bound.pass.cpp
index f2796d7b432bd56cef4cbd1403696a8ef41b36aa..99a7e374d12c3ac8808af299da7e91e0d247b6f2 100644
--- a/libcxx/test/std/containers/associative/multiset/upper_bound.pass.cpp
+++ b/libcxx/test/std/containers/associative/multiset/upper_bound.pass.cpp
@@ -20,7 +20,7 @@
 #include "min_allocator.h"
 #include "private_constructor.hpp"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int V;
@@ -219,4 +219,6 @@ int main()
     assert(r == next(m.begin(), 9));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/allocator_mismatch.fail.cpp b/libcxx/test/std/containers/associative/set/allocator_mismatch.fail.cpp
index ed36019680a49ba8e80f8ac83171ddd3ea0e3fde..69e49351e200d17fede99444a658d3f188a57879 100644
--- a/libcxx/test/std/containers/associative/set/allocator_mismatch.fail.cpp
+++ b/libcxx/test/std/containers/associative/set/allocator_mismatch.fail.cpp
@@ -11,7 +11,9 @@
 
 #include <set>
 
-int main()
+int main(int, char**)
 {
     std::set<int, std::less<int>, std::allocator<long> > s;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/clear.pass.cpp b/libcxx/test/std/containers/associative/set/clear.pass.cpp
index 3f84ee480cb3f2134c72fe634e4df1ac0df30021..0650e912fd35c12ac75ca1659a31f5572bb713a9 100644
--- a/libcxx/test/std/containers/associative/set/clear.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/clear.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::set<int> M;
@@ -62,4 +62,6 @@ int main()
         assert(m.size() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/count.pass.cpp b/libcxx/test/std/containers/associative/set/count.pass.cpp
index e915b1cde80ba41d2de12eadca45c45a42e8fbe2..8866aa7f0574f504bd80528a173ea366d2f82d75 100644
--- a/libcxx/test/std/containers/associative/set/count.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/count.pass.cpp
@@ -19,7 +19,7 @@
 #include "min_allocator.h"
 #include "private_constructor.hpp"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int V;
@@ -167,4 +167,6 @@ int main()
     }
 #endif
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/count_transparent.pass.cpp b/libcxx/test/std/containers/associative/set/count_transparent.pass.cpp
index e8490e6de08b67872891d2c53e973ae878184d02..d94188def083105e477d21a3a73d74bd7520fb4c 100644
--- a/libcxx/test/std/containers/associative/set/count_transparent.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/count_transparent.pass.cpp
@@ -42,9 +42,11 @@ struct Comp {
   }
 };
 
-int main() {
+int main(int, char**) {
   std::set<std::pair<int, int>, Comp> s{{2, 1}, {1, 2}, {1, 3}, {1, 4}, {2, 2}};
 
   auto cnt = s.count(1);
   assert(cnt == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/emplace.pass.cpp b/libcxx/test/std/containers/associative/set/emplace.pass.cpp
index fdabf02a81d53c458200e0c92dd778030e246748..e48f2e1e4474f07c55f1d1fed1d2cf289e7f8db2 100644
--- a/libcxx/test/std/containers/associative/set/emplace.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/emplace.pass.cpp
@@ -22,7 +22,7 @@
 #include "DefaultOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::set<DefaultOnly> M;
@@ -84,4 +84,6 @@ int main()
         assert(m.size() == 1);
         assert(*r.first == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/emplace_hint.pass.cpp b/libcxx/test/std/containers/associative/set/emplace_hint.pass.cpp
index 441adaf2125051ecfd83ec474e1e8162bc804ae1..a7ed7266be2084dff52bd3747c066e3cc8763e74 100644
--- a/libcxx/test/std/containers/associative/set/emplace_hint.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/emplace_hint.pass.cpp
@@ -22,7 +22,7 @@
 #include "DefaultOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::set<DefaultOnly> M;
@@ -77,4 +77,6 @@ int main()
         assert(m.size() == 1);
         assert(*r == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/empty.fail.cpp b/libcxx/test/std/containers/associative/set/empty.fail.cpp
index 7954f6f496b176f3d3031ce6ba6abc0583c0013d..fc5856fbdbf4978cadbadffb4092c518b95da8d9 100644
--- a/libcxx/test/std/containers/associative/set/empty.fail.cpp
+++ b/libcxx/test/std/containers/associative/set/empty.fail.cpp
@@ -20,8 +20,10 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     std::set<int> c;
     c.empty();  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/empty.pass.cpp b/libcxx/test/std/containers/associative/set/empty.pass.cpp
index 50ce5dd3bf7cc73b1f9b7c7d2ab63dbae51df2ae..c00ab68ffc9e4c998ebe16230d906935ec3b5c72 100644
--- a/libcxx/test/std/containers/associative/set/empty.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/empty.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::set<int> M;
@@ -39,4 +39,6 @@ int main()
     assert(m.empty());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/equal_range.pass.cpp b/libcxx/test/std/containers/associative/set/equal_range.pass.cpp
index da221aa54adc09adb8df41e6be651e28f883a694..5c43706118dff6b7251e0b7db4302b1501ee3a39 100644
--- a/libcxx/test/std/containers/associative/set/equal_range.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/equal_range.pass.cpp
@@ -20,7 +20,7 @@
 #include "min_allocator.h"
 #include "private_constructor.hpp"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int V;
@@ -367,4 +367,6 @@ int main()
     assert(r.second == next(m.begin(), 8));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/equal_range_transparent.pass.cpp b/libcxx/test/std/containers/associative/set/equal_range_transparent.pass.cpp
index c091aa6b5d88cc5eb3e56aacd064e4c1cfb73537..b69ff2d522f04bb34842d2715fe4201eb8bfe876 100644
--- a/libcxx/test/std/containers/associative/set/equal_range_transparent.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/equal_range_transparent.pass.cpp
@@ -44,7 +44,7 @@ struct Comp {
   }
 };
 
-int main() {
+int main(int, char**) {
   std::set<std::pair<int, int>, Comp> s{{2, 1}, {1, 2}, {1, 3}, {1, 4}, {2, 2}};
 
   auto er = s.equal_range(1);
@@ -56,4 +56,6 @@ int main() {
   }
 
   assert(nels == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/erase_iter.pass.cpp b/libcxx/test/std/containers/associative/set/erase_iter.pass.cpp
index 99650d3d03fa4d2d12a1fccb68a11951a56336fc..49ce4f29e77a382f57305b56bf72177595883538 100644
--- a/libcxx/test/std/containers/associative/set/erase_iter.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/erase_iter.pass.cpp
@@ -25,7 +25,7 @@ struct TemplateConstructor
 
 bool operator<(const TemplateConstructor&, const TemplateConstructor&) { return false; }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::set<int> M;
@@ -199,4 +199,6 @@ int main()
             c.erase(it);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/erase_iter_iter.pass.cpp b/libcxx/test/std/containers/associative/set/erase_iter_iter.pass.cpp
index b98d83ad8a13ce15ea6ee0adbb03956b787bd172..86fd52c2cb4e49a8907541d2e2867c7b242ef73d 100644
--- a/libcxx/test/std/containers/associative/set/erase_iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/erase_iter_iter.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::set<int> M;
@@ -137,4 +137,6 @@ int main()
         assert(i == m.end());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/erase_key.pass.cpp b/libcxx/test/std/containers/associative/set/erase_key.pass.cpp
index da3ea5c14d8b3ee7f958cd19dac779e13f81b019..3ceec88500b23eeb0a5fc313eb71938eb69111fa 100644
--- a/libcxx/test/std/containers/associative/set/erase_key.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/erase_key.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::set<int> M;
@@ -199,4 +199,6 @@ int main()
         assert(i == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/extract_iterator.pass.cpp b/libcxx/test/std/containers/associative/set/extract_iterator.pass.cpp
index da95331f7c7fb1892db034c6856b7c5d5df430b4..1ba13e318a6c0abc076557b4b805cc7ce2cb0ac1 100644
--- a/libcxx/test/std/containers/associative/set/extract_iterator.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/extract_iterator.pass.cpp
@@ -36,7 +36,7 @@ void test(Container& c)
     assert(c.size() == 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
         using set_type = std::set<int>;
@@ -56,4 +56,6 @@ int main()
         min_alloc_set m = {1, 2, 3, 4, 5, 6};
         test(m);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/extract_key.pass.cpp b/libcxx/test/std/containers/associative/set/extract_key.pass.cpp
index 68f24f6544971b93297853ab6496df3895d1bed9..4417e86367b11418b5ea442ca07afddf2230cb45 100644
--- a/libcxx/test/std/containers/associative/set/extract_key.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/extract_key.pass.cpp
@@ -43,7 +43,7 @@ void test(Container& c, KeyTypeIter first, KeyTypeIter last)
     }
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::set<int> m = {1, 2, 3, 4, 5, 6};
@@ -67,4 +67,6 @@ int main()
         int keys[] = {1, 2, 3, 4, 5, 6};
         test(m, std::begin(keys), std::end(keys));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/find.pass.cpp b/libcxx/test/std/containers/associative/set/find.pass.cpp
index 50b779afdcfe6f5f85fe4cf527bd47b6130552c6..cda1ea87aa5a315a5b8c83b56060e302e9582bc9 100644
--- a/libcxx/test/std/containers/associative/set/find.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/find.pass.cpp
@@ -20,7 +20,7 @@
 #include "min_allocator.h"
 #include "private_constructor.hpp"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int V;
@@ -237,4 +237,6 @@ int main()
     assert(r == next(m.begin(), 8));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/gcc_workaround.pass.cpp b/libcxx/test/std/containers/associative/set/gcc_workaround.pass.cpp
index 2b923b773403184e39e18a5f7fae35f4f862afc2..5f4947b54730396fa10957da1ff996efbd3eb35d 100644
--- a/libcxx/test/std/containers/associative/set/gcc_workaround.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/gcc_workaround.pass.cpp
@@ -15,7 +15,4 @@ std::set<int> s;
 using std::map;
 using std::multimap;
 
-int main(void)
-{
-       return 0;
-}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/containers/associative/set/incomplete_type.pass.cpp b/libcxx/test/std/containers/associative/set/incomplete_type.pass.cpp
index 96b2bbf591683f594519c1dad35dc2ea90401328..d3b93c59972f8585cf937093772d3b42b70cbe8d 100644
--- a/libcxx/test/std/containers/associative/set/incomplete_type.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/incomplete_type.pass.cpp
@@ -23,6 +23,8 @@ struct A {
 
 inline bool operator==(A const& L, A const& R) { return &L == &R; }
 inline bool operator<(A const& L, A const& R)  { return L.data < R.data; }
-int main() {
+int main(int, char**) {
     A a;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/insert_and_emplace_allocator_requirements.pass.cpp b/libcxx/test/std/containers/associative/set/insert_and_emplace_allocator_requirements.pass.cpp
index 8c60e699af1f2d97fee746b46bb0ead4d460f03c..11be14b02b076fb5ca36b60484afac29eea15511 100644
--- a/libcxx/test/std/containers/associative/set/insert_and_emplace_allocator_requirements.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/insert_and_emplace_allocator_requirements.pass.cpp
@@ -20,9 +20,11 @@
 #include "container_test_types.h"
 #include "../../set_allocator_requirement_test_templates.h"
 
-int main()
+int main(int, char**)
 {
   testSetInsert<TCT::set<> >();
   testSetEmplace<TCT::set<> >();
   testSetEmplaceHint<TCT::set<> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/insert_cv.pass.cpp b/libcxx/test/std/containers/associative/set/insert_cv.pass.cpp
index d29a796baa08ddbba096f78a07bb5ed471de34e6..a97e76eb57668f58fc1a85ed073d08091c58c5d7 100644
--- a/libcxx/test/std/containers/associative/set/insert_cv.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/insert_cv.pass.cpp
@@ -53,7 +53,7 @@ void do_insert_cv_test()
     assert(*r.first == 3);
 }
 
-int main()
+int main(int, char**)
 {
     do_insert_cv_test<std::set<int> >();
 #if TEST_STD_VER >= 11
@@ -62,4 +62,6 @@ int main()
         do_insert_cv_test<M>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/insert_initializer_list.pass.cpp b/libcxx/test/std/containers/associative/set/insert_initializer_list.pass.cpp
index 46fdecd4fd73d9b842f521b7cea1c220f3bed9cf..ce5cc6fd2d74575eb9141172eb0a7f361289f374 100644
--- a/libcxx/test/std/containers/associative/set/insert_initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/insert_initializer_list.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::set<int> C;
@@ -56,4 +56,6 @@ int main()
     assert(*++i == V(8));
     assert(*++i == V(10));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/insert_iter_cv.pass.cpp b/libcxx/test/std/containers/associative/set/insert_iter_cv.pass.cpp
index ab8834e6af8ff6ed438922b1014b39ee19b93b2b..be27e5e4e07549cc0dd6a2a1cb2e57158371af81 100644
--- a/libcxx/test/std/containers/associative/set/insert_iter_cv.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/insert_iter_cv.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::set<int> M;
@@ -69,4 +69,6 @@ int main()
         assert(*r == 3);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/insert_iter_iter.pass.cpp b/libcxx/test/std/containers/associative/set/insert_iter_iter.pass.cpp
index bf55e31a8becec29d8bddf4e02a22eaccb010bc0..35c2dca30f48c852438f005bd0a8c9c77643a04d 100644
--- a/libcxx/test/std/containers/associative/set/insert_iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/insert_iter_iter.pass.cpp
@@ -19,7 +19,7 @@
 #include "test_iterators.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::set<int> M;
@@ -69,4 +69,6 @@ int main()
         assert(*next(m.begin(), 2) == 3);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/insert_iter_rv.pass.cpp b/libcxx/test/std/containers/associative/set/insert_iter_rv.pass.cpp
index dfe3b52da6c97e674d0d61e58bb0f5346f753452..08eba9fe60fb1155358195824ec80c30f2c8f59f 100644
--- a/libcxx/test/std/containers/associative/set/insert_iter_rv.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/insert_iter_rv.pass.cpp
@@ -20,7 +20,7 @@
 #include "MoveOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::set<MoveOnly> M;
@@ -70,4 +70,6 @@ int main()
         assert(m.size() == 3);
         assert(*r == 3);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/insert_node_type.pass.cpp b/libcxx/test/std/containers/associative/set/insert_node_type.pass.cpp
index 51826f4fd5ab89e1fb899e452c2ef5d3fcf4b30a..188aea2bb0af223111c739ffc2342e5737989985 100644
--- a/libcxx/test/std/containers/associative/set/insert_node_type.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/insert_node_type.pass.cpp
@@ -73,10 +73,12 @@ void test(Container& c)
     }
 }
 
-int main()
+int main(int, char**)
 {
     std::set<int> m;
     test(m);
     std::set<int, std::less<int>, min_allocator<int>> m2;
     test(m2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/insert_node_type_hint.pass.cpp b/libcxx/test/std/containers/associative/set/insert_node_type_hint.pass.cpp
index 2595a3ca27c4e11a89400f34751245903e1e81fd..6e8c140997c80318bb67aa6ffad64807d7c499ec 100644
--- a/libcxx/test/std/containers/associative/set/insert_node_type_hint.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/insert_node_type_hint.pass.cpp
@@ -51,10 +51,12 @@ void test(Container& c)
     }
 }
 
-int main()
+int main(int, char**)
 {
     std::set<int> m;
     test(m);
     std::set<int, std::less<int>, min_allocator<int>> m2;
     test(m2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/insert_rv.pass.cpp b/libcxx/test/std/containers/associative/set/insert_rv.pass.cpp
index 567243ad5b974449d0e77f42c4bc925c34148ee4..092fd8a710b5aca0bf16db1a1636ede829393199 100644
--- a/libcxx/test/std/containers/associative/set/insert_rv.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/insert_rv.pass.cpp
@@ -20,7 +20,7 @@
 #include "MoveOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::set<MoveOnly> M;
@@ -78,4 +78,6 @@ int main()
         assert(m.size() == 3);
         assert(*r.first == 3);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/iterator.pass.cpp b/libcxx/test/std/containers/associative/set/iterator.pass.cpp
index 5212e3fcfa340c08c0bfc66e4ba92375b8e8ef4a..da0f9a7b946a7a982bf9bf8d5ef632f007122cac 100644
--- a/libcxx/test/std/containers/associative/set/iterator.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/iterator.pass.cpp
@@ -32,7 +32,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int V;
@@ -209,4 +209,6 @@ int main()
         assert (!(cii != ii1 ));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/lower_bound.pass.cpp b/libcxx/test/std/containers/associative/set/lower_bound.pass.cpp
index b363524d412fca964519201950f10482944c274f..9a25950a8515e2e9e052669250cc032363d47e5a 100644
--- a/libcxx/test/std/containers/associative/set/lower_bound.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/lower_bound.pass.cpp
@@ -20,7 +20,7 @@
 #include "min_allocator.h"
 #include "private_constructor.hpp"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int V;
@@ -334,4 +334,6 @@ int main()
     }
 #endif
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/max_size.pass.cpp b/libcxx/test/std/containers/associative/set/max_size.pass.cpp
index 8c2c5fd281a9e9c033163a695b2ae4604be049c0..e37bfe7142b06511135832f68ce607af29a54cfd 100644
--- a/libcxx/test/std/containers/associative/set/max_size.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/max_size.pass.cpp
@@ -20,7 +20,7 @@
 #include "test_allocator.h"
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
       typedef limited_allocator<int, 10> A;
@@ -46,4 +46,6 @@ int main()
       assert(c.max_size() <= max_dist);
       assert(c.max_size() <= alloc_max_size(c.get_allocator()));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/merge.pass.cpp b/libcxx/test/std/containers/associative/set/merge.pass.cpp
index a8b22ea3df34b34928c36490f05e947e158e3e74..62e76ba069bcf1a235960d41c660b76972f57181 100644
--- a/libcxx/test/std/containers/associative/set/merge.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/merge.pass.cpp
@@ -49,7 +49,7 @@ struct throw_comparator
 };
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         std::set<int> src{1, 3, 5};
@@ -145,4 +145,5 @@ int main()
             first.merge(std::move(second));
         }
     }
+    return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/set.cons/alloc.pass.cpp b/libcxx/test/std/containers/associative/set/set.cons/alloc.pass.cpp
index 87bdb7aec7d3231efd68d2c8898c00803902afed..591b28c184b9b25b952c5e9c3d37067e769300ab 100644
--- a/libcxx/test/std/containers/associative/set/set.cons/alloc.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/set.cons/alloc.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::less<int> C;
     typedef test_allocator<int> A;
@@ -25,4 +25,6 @@ int main()
     assert(m.empty());
     assert(m.begin() == m.end());
     assert(m.get_allocator() == A(5));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/set.cons/assign_initializer_list.pass.cpp b/libcxx/test/std/containers/associative/set/set.cons/assign_initializer_list.pass.cpp
index 269ae11758f3ba96872adf02189d583505a44df2..0127b1d8147bf7e4d0b214a4291669da8650d266 100644
--- a/libcxx/test/std/containers/associative/set/set.cons/assign_initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/set.cons/assign_initializer_list.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::set<int> C;
@@ -51,4 +51,6 @@ int main()
     assert(*++i == V(5));
     assert(*++i == V(6));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/set.cons/compare.pass.cpp b/libcxx/test/std/containers/associative/set/set.cons/compare.pass.cpp
index 4a6978d9543930dc6935cefdb51bc77599260337..a4e9718e2b40dba5ae3382949e482ba102a70a0c 100644
--- a/libcxx/test/std/containers/associative/set/set.cons/compare.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/set.cons/compare.pass.cpp
@@ -21,7 +21,7 @@
 
 #include "../../../test_compare.h"
 
-int main()
+int main(int, char**)
 {
     typedef test_compare<std::less<int> > C;
     const std::set<int, C> m(C(3));
@@ -29,4 +29,6 @@ int main()
     assert(m.begin() == m.end());
     assert(m.key_comp() == C(3));
     assert(m.value_comp() == C(3));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/set.cons/compare_alloc.pass.cpp b/libcxx/test/std/containers/associative/set/set.cons/compare_alloc.pass.cpp
index 8264c3f81051da7f3f0aa1f8d2311014efc3ac60..41c7d02894b1f9e6867076781408721b8a3763bc 100644
--- a/libcxx/test/std/containers/associative/set/set.cons/compare_alloc.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/set.cons/compare_alloc.pass.cpp
@@ -18,7 +18,7 @@
 #include "../../../test_compare.h"
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     typedef test_compare<std::less<int> > C;
     typedef test_allocator<int> A;
@@ -27,4 +27,6 @@ int main()
     assert(m.begin() == m.end());
     assert(m.key_comp() == C(4));
     assert(m.get_allocator() == A(5));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/set.cons/compare_copy_constructible.fail.cpp b/libcxx/test/std/containers/associative/set/set.cons/compare_copy_constructible.fail.cpp
index 84c0b4ea0a95e424f491fa4078bb25bdf53c063f..58f678dd1a415cddbc01f68dbaeaa89928a2042d 100644
--- a/libcxx/test/std/containers/associative/set/set.cons/compare_copy_constructible.fail.cpp
+++ b/libcxx/test/std/containers/associative/set/set.cons/compare_copy_constructible.fail.cpp
@@ -23,6 +23,8 @@ private:
     };
 
 
-int main() {
+int main(int, char**) {
     std::set<int, Comp<int> > m;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/set.cons/copy.pass.cpp b/libcxx/test/std/containers/associative/set/set.cons/copy.pass.cpp
index 529d951d282a3b4c6b85dbc37f05572e2c40ee9c..2e256aa172121f68c107cacf6ecf9bfef8ec998a 100644
--- a/libcxx/test/std/containers/associative/set/set.cons/copy.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/set.cons/copy.pass.cpp
@@ -19,7 +19,7 @@
 #include "../../../test_compare.h"
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int V;
@@ -91,4 +91,6 @@ int main()
         assert(*next(mo.begin(), 2) == 3);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/set.cons/copy_alloc.pass.cpp b/libcxx/test/std/containers/associative/set/set.cons/copy_alloc.pass.cpp
index 09e7f84ee2f0b721ef586867ff127562affd1fc8..6b1010c33ff273126944d74759d50b47b6cfd9ed 100644
--- a/libcxx/test/std/containers/associative/set/set.cons/copy_alloc.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/set.cons/copy_alloc.pass.cpp
@@ -18,7 +18,7 @@
 #include "../../../test_compare.h"
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     typedef int V;
     V ar[] =
@@ -52,4 +52,6 @@ int main()
     assert(*mo.begin() == 1);
     assert(*next(mo.begin()) == 2);
     assert(*next(mo.begin(), 2) == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/set.cons/copy_assign.pass.cpp b/libcxx/test/std/containers/associative/set/set.cons/copy_assign.pass.cpp
index d89c278137b21d0c00107df62556eaa190dd6d88..c1f37f83dcc8675e0dd7182b6bb6476b1f233429 100644
--- a/libcxx/test/std/containers/associative/set/set.cons/copy_assign.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/set.cons/copy_assign.pass.cpp
@@ -18,7 +18,7 @@
 #include "../../../test_compare.h"
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int V;
@@ -105,4 +105,6 @@ int main()
         assert(*next(mo.begin()) == 2);
         assert(*next(mo.begin(), 2) == 3);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/set.cons/default.pass.cpp b/libcxx/test/std/containers/associative/set/set.cons/default.pass.cpp
index 16137d7cc9703b502c37db1f9759971aa4b286ad..88dc3a262c803915a1076907536f913e531a9fa1 100644
--- a/libcxx/test/std/containers/associative/set/set.cons/default.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/set.cons/default.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::set<int> m;
@@ -50,4 +50,6 @@ int main()
     assert(m.begin() == m.end());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/set.cons/default_noexcept.pass.cpp b/libcxx/test/std/containers/associative/set/set.cons/default_noexcept.pass.cpp
index 0c25901be30ba1e7eb2947c4c79cfc87a626e191..0305e20f2eecd461af2667bfdb0f4eabcc02a918 100644
--- a/libcxx/test/std/containers/associative/set/set.cons/default_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/set.cons/default_noexcept.pass.cpp
@@ -33,7 +33,7 @@ struct some_comp
     bool operator()(const T&, const T&) const { return false; }
 };
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -53,4 +53,6 @@ int main()
         typedef std::set<MoveOnly, some_comp<MoveOnly>> C;
         static_assert(!std::is_nothrow_default_constructible<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/set.cons/dtor_noexcept.pass.cpp b/libcxx/test/std/containers/associative/set/set.cons/dtor_noexcept.pass.cpp
index 9ee68bf6d76a03bf4302bfce098f3f0fbabde629..a06a47168d294e01121e2b06fddf40a83fc35474 100644
--- a/libcxx/test/std/containers/associative/set/set.cons/dtor_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/set.cons/dtor_noexcept.pass.cpp
@@ -27,7 +27,7 @@ struct some_comp
     bool operator()(const T&, const T&) const { return false; }
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::set<MoveOnly> C;
@@ -47,4 +47,6 @@ int main()
         static_assert(!std::is_nothrow_destructible<C>::value, "");
     }
 #endif // _LIBCPP_VERSION
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/set.cons/initializer_list.pass.cpp b/libcxx/test/std/containers/associative/set/set.cons/initializer_list.pass.cpp
index a0cba90bd3e6883914023b5e2321532f1ef604a0..e4742bbdae0567417892a0e8c6ab19f8d0ddaff6 100644
--- a/libcxx/test/std/containers/associative/set/set.cons/initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/set.cons/initializer_list.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::set<int> C;
@@ -49,4 +49,6 @@ int main()
     assert(*++i == V(5));
     assert(*++i == V(6));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/set.cons/initializer_list_compare.pass.cpp b/libcxx/test/std/containers/associative/set/set.cons/initializer_list_compare.pass.cpp
index a0448cdbcba2105e14886100da3cea6e10629f61..cf4b78af9343cb0cca3ca677d4aa770707b8e441 100644
--- a/libcxx/test/std/containers/associative/set/set.cons/initializer_list_compare.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/set.cons/initializer_list_compare.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include "../../../test_compare.h"
 
-int main()
+int main(int, char**)
 {
     typedef test_compare<std::less<int> > Cmp;
     typedef std::set<int, Cmp> C;
@@ -34,4 +34,6 @@ int main()
     assert(*++i == V(5));
     assert(*++i == V(6));
     assert(m.key_comp() == Cmp(10));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/set.cons/initializer_list_compare_alloc.pass.cpp b/libcxx/test/std/containers/associative/set/set.cons/initializer_list_compare_alloc.pass.cpp
index 40990948b7b5e1985474c2bf376af76c129b1df7..161cdd8c1c3c1c56a3959b2444e8949bbccc2ac5 100644
--- a/libcxx/test/std/containers/associative/set/set.cons/initializer_list_compare_alloc.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/set.cons/initializer_list_compare_alloc.pass.cpp
@@ -21,7 +21,7 @@
 #include "../../../test_compare.h"
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef test_compare<std::less<int> > Cmp;
@@ -58,4 +58,6 @@ int main()
     assert(*++i == V(6));
     assert(m.get_allocator() == A(4));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/set.cons/iter_iter.pass.cpp b/libcxx/test/std/containers/associative/set/set.cons/iter_iter.pass.cpp
index 913efe0da62da292da76f58716caeeb1af87bda8..25143a7df100bd2860363f19799b14eb50ba38e0 100644
--- a/libcxx/test/std/containers/associative/set/set.cons/iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/set.cons/iter_iter.pass.cpp
@@ -19,7 +19,7 @@
 #include "test_iterators.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int V;
@@ -67,4 +67,6 @@ int main()
     assert(*next(m.begin(), 2) == 3);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/set.cons/iter_iter_alloc.pass.cpp b/libcxx/test/std/containers/associative/set/set.cons/iter_iter_alloc.pass.cpp
index 6e3625d0540e3bf12ad0da331d165dc6b5280983..bf8b97098314c54cb68e42c500f74aa30ad74c45 100644
--- a/libcxx/test/std/containers/associative/set/set.cons/iter_iter_alloc.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/set.cons/iter_iter_alloc.pass.cpp
@@ -26,7 +26,7 @@
 #include "../../../test_compare.h"
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int V;
@@ -83,4 +83,6 @@ int main()
     assert(m.get_allocator() == a);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/set.cons/iter_iter_comp.pass.cpp b/libcxx/test/std/containers/associative/set/set.cons/iter_iter_comp.pass.cpp
index b75cccc4e40c5d1830edc4f2eaecb7fa4d51be69..f9c2e4a98ef238c2e72b5fd629dcc29ea53f185d 100644
--- a/libcxx/test/std/containers/associative/set/set.cons/iter_iter_comp.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/set.cons/iter_iter_comp.pass.cpp
@@ -19,7 +19,7 @@
 #include "test_iterators.h"
 #include "../../../test_compare.h"
 
-int main()
+int main(int, char**)
 {
     typedef int V;
     V ar[] =
@@ -43,4 +43,6 @@ int main()
     assert(*m.begin() == 1);
     assert(*next(m.begin()) == 2);
     assert(*next(m.begin(), 2) == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/set.cons/move.pass.cpp b/libcxx/test/std/containers/associative/set/set.cons/move.pass.cpp
index b2d7b0429b8c3a9a3e97f4aa7ded063749403bb2..516274efca400b67ebad12a01388b033fc8c6f1a 100644
--- a/libcxx/test/std/containers/associative/set/set.cons/move.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/set.cons/move.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int V;
@@ -101,4 +101,6 @@ int main()
         assert(mo.size() == 0);
         assert(distance(mo.begin(), mo.end()) == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/set.cons/move_alloc.pass.cpp b/libcxx/test/std/containers/associative/set/set.cons/move_alloc.pass.cpp
index 7bae3ed210eb32d9668f95481877a12af9b9a694..db7933e92b8fd682b7181e6dab8eba43f59ba9fb 100644
--- a/libcxx/test/std/containers/associative/set/set.cons/move_alloc.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/set.cons/move_alloc.pass.cpp
@@ -23,7 +23,7 @@
 #include "test_allocator.h"
 #include "Counter.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef MoveOnly V;
@@ -185,4 +185,6 @@ int main()
         assert(Counter_base::gConstructed == 0);
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/set.cons/move_assign.pass.cpp b/libcxx/test/std/containers/associative/set/set.cons/move_assign.pass.cpp
index bbd787151ab270f988c5dffc38518e843a15f321..ba5c767f30bc1dffa7e025579b411f291e3c7375 100644
--- a/libcxx/test/std/containers/associative/set/set.cons/move_assign.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/set.cons/move_assign.pass.cpp
@@ -22,7 +22,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef MoveOnly V;
@@ -180,4 +180,6 @@ int main()
         assert(m3.key_comp() == C(5));
         assert(m1.empty());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/set.cons/move_assign_noexcept.pass.cpp b/libcxx/test/std/containers/associative/set/set.cons/move_assign_noexcept.pass.cpp
index 408227e8db34513f4553930d68ef5adadbb9b381..f6e3c9f32e6a3e875b8389663c8878150872430c 100644
--- a/libcxx/test/std/containers/associative/set/set.cons/move_assign_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/set.cons/move_assign_noexcept.pass.cpp
@@ -33,7 +33,7 @@ struct some_comp
     bool operator()(const T&, const T&) const { return false; }
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::set<MoveOnly> C;
@@ -53,4 +53,6 @@ int main()
         typedef std::set<MoveOnly, some_comp<MoveOnly>> C;
         static_assert(!std::is_nothrow_move_assignable<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/set.cons/move_noexcept.pass.cpp b/libcxx/test/std/containers/associative/set/set.cons/move_noexcept.pass.cpp
index 6945aa39e45efb8d761669090678e2766aa938b8..2bcd26de6372470951f79b430cd940a29f7d81df 100644
--- a/libcxx/test/std/containers/associative/set/set.cons/move_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/set.cons/move_noexcept.pass.cpp
@@ -31,7 +31,7 @@ struct some_comp
     bool operator()(const T&, const T&) const { return false; }
 };
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -51,4 +51,6 @@ int main()
         typedef std::set<MoveOnly, some_comp<MoveOnly>> C;
         static_assert(!std::is_nothrow_move_constructible<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/set.erasure/erase_if.pass.cpp b/libcxx/test/std/containers/associative/set/set.erasure/erase_if.pass.cpp
index 3eecab797af7fd661d4253316de2e721bf2c6a13..43a60d79c02cfc18281c9f30c2792ec5b3f519e5 100644
--- a/libcxx/test/std/containers/associative/set/set.erasure/erase_if.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/set.erasure/erase_if.pass.cpp
@@ -55,7 +55,7 @@ void test()
     test0(S({1,2,3}), False, S({1,2,3}));
 }
 
-int main()
+int main(int, char**)
 {
     test<std::set<int>>();
     test<std::set<int, std::less<int>, min_allocator<int>>> ();
@@ -63,4 +63,6 @@ int main()
 
     test<std::set<long>>();
     test<std::set<double>>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/set.special/member_swap.pass.cpp b/libcxx/test/std/containers/associative/set/set.special/member_swap.pass.cpp
index 02324a36aee7d32bdf109e96a2fa8fd8de00b2d8..455c34ec89bb8993e4230cd1b34dda38c830ab40 100644
--- a/libcxx/test/std/containers/associative/set/set.special/member_swap.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/set.special/member_swap.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int V;
@@ -173,4 +173,6 @@ int main()
     }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/set.special/non_member_swap.pass.cpp b/libcxx/test/std/containers/associative/set/set.special/non_member_swap.pass.cpp
index 2420dabf6a422d36224349447221304af9f7892b..b111de9cac6892e396fa071f2090158a4777f6a7 100644
--- a/libcxx/test/std/containers/associative/set/set.special/non_member_swap.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/set.special/non_member_swap.pass.cpp
@@ -17,7 +17,7 @@
 #include "test_allocator.h"
 #include "../../../test_compare.h"
 
-int main()
+int main(int, char**)
 {
     typedef int V;
     {
@@ -163,4 +163,6 @@ int main()
         assert(m2.key_comp() == C(1));
         assert(m2.get_allocator() == A(1));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/set.special/swap_noexcept.pass.cpp b/libcxx/test/std/containers/associative/set/set.special/swap_noexcept.pass.cpp
index fc0eba646e5e14d58bb7f73e7c8f1159ca0e19f3..9fd68f66395643b3b8bd5f2a4e9e7258bc375f73 100644
--- a/libcxx/test/std/containers/associative/set/set.special/swap_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/set.special/swap_noexcept.pass.cpp
@@ -91,7 +91,7 @@ struct some_alloc3
     typedef std::false_type is_always_equal;
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::set<MoveOnly> C;
@@ -137,4 +137,6 @@ int main()
 #endif // _LIBCPP_VERSION
 #endif
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/size.pass.cpp b/libcxx/test/std/containers/associative/set/size.pass.cpp
index 93b23472540dba5a2dfa352d093a717fef27915d..b73d833769c2e75f88a6687a8ee7475da8f49483 100644
--- a/libcxx/test/std/containers/associative/set/size.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/size.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::set<int> M;
@@ -55,4 +55,6 @@ int main()
     assert(m.size() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/types.pass.cpp b/libcxx/test/std/containers/associative/set/types.pass.cpp
index 3b8c0983b1ee617dc34d4a83e7ff9282edfab43a..5c7bd25a5b558a8910956c85af3ea3d585badf19 100644
--- a/libcxx/test/std/containers/associative/set/types.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/types.pass.cpp
@@ -33,7 +33,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::set<int> C;
@@ -66,4 +66,6 @@ int main()
     static_assert((std::is_same<C::difference_type, std::ptrdiff_t>::value), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/associative/set/upper_bound.pass.cpp b/libcxx/test/std/containers/associative/set/upper_bound.pass.cpp
index 315268a600add0039c7edf0fd3767eac6da3a806..3649a5c045590c2914d3d88b2c56deefcd6fbd38 100644
--- a/libcxx/test/std/containers/associative/set/upper_bound.pass.cpp
+++ b/libcxx/test/std/containers/associative/set/upper_bound.pass.cpp
@@ -20,7 +20,7 @@
 #include "min_allocator.h"
 #include "private_constructor.hpp"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int V;
@@ -333,4 +333,6 @@ int main()
     assert(r == next(m.begin(), 8));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/nothing_to_do.pass.cpp b/libcxx/test/std/containers/container.adaptors/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/containers/container.adaptors/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons.alloc/ctor_alloc.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons.alloc/ctor_alloc.pass.cpp
index 293356b386a50d1a5543de2609a3f26898a4be79..59547203b49b7536ef2181c8d2d50f3851547549 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons.alloc/ctor_alloc.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons.alloc/ctor_alloc.pass.cpp
@@ -40,9 +40,11 @@ struct test
     using base::c;
 };
 
-int main()
+int main(int, char**)
 {
     test<int> q((test_allocator<int>(3)));
     assert(q.c.get_allocator() == test_allocator<int>(3));
     assert(q.c.size() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons.alloc/ctor_comp_alloc.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons.alloc/ctor_comp_alloc.pass.cpp
index 58d61b70eb2ffd0c96b453b10e13e8cbb9d8c72d..40f6bc473c7a777fa00cbc8f45a227cb2ca2c2ac 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons.alloc/ctor_comp_alloc.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons.alloc/ctor_comp_alloc.pass.cpp
@@ -40,9 +40,11 @@ struct test
     using base::c;
 };
 
-int main()
+int main(int, char**)
 {
     test<int> q(std::less<int>(), test_allocator<int>(3));
     assert(q.c.get_allocator() == test_allocator<int>(3));
     assert(q.c.size() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons.alloc/ctor_comp_cont_alloc.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons.alloc/ctor_comp_cont_alloc.pass.cpp
index 39c4955659ba97e053799e31e61d0985e2587a3c..1f3dd7fbd1679ff52cd3610e737934d0f2adf654 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons.alloc/ctor_comp_cont_alloc.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons.alloc/ctor_comp_cont_alloc.pass.cpp
@@ -51,7 +51,7 @@ struct test
     using base::c;
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::vector<int, test_allocator<int> > C;
     C v = make<C>(5);
@@ -59,4 +59,6 @@ int main()
     assert(q.c.get_allocator() == test_allocator<int>(3));
     assert(q.size() == 5);
     assert(q.top() == 4);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons.alloc/ctor_comp_rcont_alloc.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons.alloc/ctor_comp_rcont_alloc.pass.cpp
index 4609064735fe58ff6d0f2a9fdb9766cfb8d65cdb..3956f9b974e6191d69e88a7eb3a587a753fe412d 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons.alloc/ctor_comp_rcont_alloc.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons.alloc/ctor_comp_rcont_alloc.pass.cpp
@@ -51,11 +51,13 @@ struct test
     using base::c;
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::vector<int, test_allocator<int> > C;
     test<int> q(std::less<int>(), make<C>(5), test_allocator<int>(3));
     assert(q.c.get_allocator() == test_allocator<int>(3));
     assert(q.size() == 5);
     assert(q.top() == 4);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons.alloc/ctor_copy_alloc.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons.alloc/ctor_copy_alloc.pass.cpp
index 69ed27c073c21eb62887f4247f78c7c0c3551efa..c461718430c57a159a1c30a9274b84ad10b74eea 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons.alloc/ctor_copy_alloc.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons.alloc/ctor_copy_alloc.pass.cpp
@@ -45,7 +45,7 @@ struct test
     using base::c;
 };
 
-int main()
+int main(int, char**)
 {
     test<int> qo(std::less<int>(),
                       make<std::vector<int, test_allocator<int> > >(5),
@@ -54,4 +54,6 @@ int main()
     assert(q.size() == 5);
     assert(q.c.get_allocator() == test_allocator<int>(6));
     assert(q.top() == int(4));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons.alloc/ctor_move_alloc.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons.alloc/ctor_move_alloc.pass.cpp
index d1ca38e022bd44aae8a5772917614dd76f70d1bb..98dc207c19990f357bac896710b49d130626a4bb 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons.alloc/ctor_move_alloc.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons.alloc/ctor_move_alloc.pass.cpp
@@ -53,7 +53,7 @@ struct test
 };
 
 
-int main()
+int main(int, char**)
 {
     test<MoveOnly> qo(std::less<MoveOnly>(),
                       make<std::vector<MoveOnly, test_allocator<MoveOnly> > >(5),
@@ -62,4 +62,6 @@ int main()
     assert(q.size() == 5);
     assert(q.c.get_allocator() == test_allocator<MoveOnly>(6));
     assert(q.top() == MoveOnly(4));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/assign_copy.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/assign_copy.pass.cpp
index 12c64256111f445f30365b088f995b4f6cd797b8..5b7760d0546db34494cdaebfe3d569e35e6a158e 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/assign_copy.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/assign_copy.pass.cpp
@@ -24,7 +24,7 @@ make(int n)
     return c;
 }
 
-int main()
+int main(int, char**)
 {
     std::vector<int> v = make<std::vector<int> >(5);
     std::priority_queue<int, std::vector<int>, std::greater<int> > qo(std::greater<int>(), v);
@@ -32,4 +32,6 @@ int main()
     q = qo;
     assert(q.size() == 5);
     assert(q.top() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/assign_move.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/assign_move.pass.cpp
index 61499209478e491df6667d49bd62aa2ed26a3e6e..20f62d9bf64eb2fab53b22da96a49e4de048486d 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/assign_move.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/assign_move.pass.cpp
@@ -29,11 +29,13 @@ make(int n)
 }
 
 
-int main()
+int main(int, char**)
 {
     std::priority_queue<MoveOnly> qo(std::less<MoveOnly>(), make<std::vector<MoveOnly> >(5));
     std::priority_queue<MoveOnly> q;
     q = std::move(qo);
     assert(q.size() == 5);
     assert(q.top() == MoveOnly(4));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_comp.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_comp.pass.cpp
index a195b10fc50280d828dfc731818079fc24730710..02f1bcaf0592b7c24527a6cdc2592bc870a8a1cf 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_comp.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_comp.pass.cpp
@@ -15,7 +15,7 @@
 
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     std::priority_queue<int, std::vector<int, limited_allocator<int, 10> > > q((std::less<int>()));
     assert(q.size() == 0);
@@ -23,4 +23,6 @@ int main()
     q.push(2);
     assert(q.size() == 2);
     assert(q.top() == 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_comp_container.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_comp_container.pass.cpp
index 561b5d48deda7646ecd207d7144d45b74700d5dc..487b86c5f52cc23242d1a3182c6dbb3f4d48b24c 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_comp_container.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_comp_container.pass.cpp
@@ -24,10 +24,12 @@ make(int n)
     return c;
 }
 
-int main()
+int main(int, char**)
 {
     std::vector<int> v = make<std::vector<int> >(5);
     std::priority_queue<int, std::vector<int>, std::greater<int> > q(std::greater<int>(), v);
     assert(q.size() == 5);
     assert(q.top() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_comp_rcontainer.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_comp_rcontainer.pass.cpp
index cb3b97997fa4d5354d9c974bd84e0f3c50a42b4f..47980032c05d6ecd7d50edb28032c2b0e12337b2 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_comp_rcontainer.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_comp_rcontainer.pass.cpp
@@ -29,9 +29,11 @@ make(int n)
 }
 
 
-int main()
+int main(int, char**)
 {
     std::priority_queue<MoveOnly> q(std::less<MoveOnly>(), make<std::vector<MoveOnly> >(5));
     assert(q.size() == 5);
     assert(q.top() == MoveOnly(4));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_copy.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_copy.pass.cpp
index 1c63f71520cadfaa503db948a12c12ae54106cff..fa8bae2b91bfeadfe3325d0dec1fbd23a77a7ac5 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_copy.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_copy.pass.cpp
@@ -24,11 +24,13 @@ make(int n)
     return c;
 }
 
-int main()
+int main(int, char**)
 {
     std::vector<int> v = make<std::vector<int> >(5);
     std::priority_queue<int, std::vector<int>, std::greater<int> > qo(std::greater<int>(), v);
     std::priority_queue<int, std::vector<int>, std::greater<int> > q = qo;
     assert(q.size() == 5);
     assert(q.top() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_default.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_default.pass.cpp
index ae0e7badb6d40940441a148031945f204fcd91bb..4c8dd524aebf482d7565ab3fa485a85c7da66972 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_default.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_default.pass.cpp
@@ -15,7 +15,7 @@
 
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     std::priority_queue<int, std::vector<int, limited_allocator<int, 10> > > q;
     assert(q.size() == 0);
@@ -23,4 +23,6 @@ int main()
     q.push(2);
     assert(q.size() == 2);
     assert(q.top() == 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_iter_iter.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_iter_iter.pass.cpp
index d1cda2029cab04b7f46686e8eade4185941140c4..d2afe72cad5d4d11a5011693f5973ee3b639dde1 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_iter_iter.pass.cpp
@@ -15,11 +15,13 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     int a[] = {3, 5, 2, 0, 6, 8, 1};
     int* an = a + sizeof(a)/sizeof(a[0]);
     std::priority_queue<int> q(a, an);
     assert(q.size() == static_cast<std::size_t>(an - a));
     assert(q.top() == 8);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_iter_iter_comp.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_iter_iter_comp.pass.cpp
index c147b5cfd5000982a6010d4b22b6fe94d3ac4014..caee12f0f5e4e06cb7dcea47bbc0f6c6777607ed 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_iter_iter_comp.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_iter_iter_comp.pass.cpp
@@ -16,7 +16,7 @@
 #include <functional>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     int a[] = {3, 5, 2, 0, 6, 8, 1};
     int* an = a + sizeof(a)/sizeof(a[0]);
@@ -24,4 +24,6 @@ int main()
         q(a, an, std::greater<int>());
     assert(q.size() == static_cast<std::size_t>(an - a));
     assert(q.top() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_iter_iter_comp_cont.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_iter_iter_comp_cont.pass.cpp
index b5dd515da13e11141d5ebab91fbe4286ebd10092..0b0766792408634849ae9d83adda3d22222013a8 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_iter_iter_comp_cont.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_iter_iter_comp_cont.pass.cpp
@@ -15,7 +15,7 @@
 #include <queue>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a[] = {3, 5, 2, 0, 6, 8, 1};
     const int n = sizeof(a)/sizeof(a[0]);
@@ -23,4 +23,6 @@ int main()
     std::priority_queue<int> q(a+n/2, a+n, std::less<int>(), v);
     assert(q.size() == n);
     assert(q.top() == 8);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_iter_iter_comp_rcont.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_iter_iter_comp_rcont.pass.cpp
index f2f78685f2471b2e9dd3ec4c78c7a078cf97a990..6bc4417f4785996bbe98750556996aaf263de0b9 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_iter_iter_comp_rcont.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_iter_iter_comp_rcont.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "MoveOnly.h"
 
-int main()
+int main(int, char**)
 {
     int a[] = {3, 5, 2, 0, 6, 8, 1};
     const int n = sizeof(a)/sizeof(a[0]);
@@ -28,4 +28,6 @@ int main()
                                     std::vector<MoveOnly>(a, a+n/2));
     assert(q.size() == n);
     assert(q.top() == MoveOnly(8));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_move.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_move.pass.cpp
index 445bdb56675a30e52146ad4054ff34edf1187513..4158012445abe44fe2a0daa1f25181fb51d65e87 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_move.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/ctor_move.pass.cpp
@@ -29,10 +29,12 @@ make(int n)
 }
 
 
-int main()
+int main(int, char**)
 {
     std::priority_queue<MoveOnly> qo(std::less<MoveOnly>(), make<std::vector<MoveOnly> >(5));
     std::priority_queue<MoveOnly> q = std::move(qo);
     assert(q.size() == 5);
     assert(q.top() == MoveOnly(4));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/deduct.fail.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/deduct.fail.cpp
index a37e372edc6c78d5d7369a6c2c7e7bb735914cb2..a6e579a44562a0bd22c7f7203f9f4d7c402a4321 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/deduct.fail.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/deduct.fail.cpp
@@ -17,7 +17,7 @@
 #include <cstddef>
 
 
-int main()
+int main(int, char**)
 {
 //  Test the explicit deduction guides
     {
@@ -54,4 +54,6 @@ int main()
 //      stack<allocator<int>, allocator<allocator<int>>>
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/deduct.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/deduct.pass.cpp
index f175c7d14898f8afd69d34a5f87280cc146c5a24..45d39ad3ed7ad3ac855f63743d4a793eb0f64967 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/deduct.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/deduct.pass.cpp
@@ -38,7 +38,7 @@
 
 struct A {};
 
-int main()
+int main(int, char**)
 {
 
 //  Test the explicit deduction guides
@@ -119,4 +119,6 @@ int main()
     assert(pri.size() == 4);
     assert(pri.top() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/default_noexcept.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/default_noexcept.pass.cpp
index fa0e92a1663adab26fd6d92dbda6ea3e0803b76b..d738a553eaf7cffa67b428b73e3d5bb2960d4041 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/default_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/default_noexcept.pass.cpp
@@ -23,7 +23,7 @@
 #include "test_macros.h"
 #include "MoveOnly.h"
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -31,4 +31,6 @@ int main()
         static_assert(std::is_nothrow_default_constructible<C>::value, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/dtor_noexcept.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/dtor_noexcept.pass.cpp
index a6418a3c77bd3cc71ad23cbbd4f58bc842aad184..af583a9e27a75d907983a79295300a85c15a252d 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/dtor_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/dtor_noexcept.pass.cpp
@@ -17,10 +17,12 @@
 
 #include "MoveOnly.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::priority_queue<MoveOnly> C;
         static_assert(std::is_nothrow_destructible<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/move_assign_noexcept.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/move_assign_noexcept.pass.cpp
index 8c3800ba21ea1b6f334bb41896fd801f608241f4..3fbd53dc43e01f7562fb978fafb7cecbea532fbd 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/move_assign_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/move_assign_noexcept.pass.cpp
@@ -21,10 +21,12 @@
 
 #include "MoveOnly.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::priority_queue<MoveOnly> C;
         static_assert(std::is_nothrow_move_assignable<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/move_noexcept.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/move_noexcept.pass.cpp
index ae6eb4b087d6981c27157fde1842ce87b9218260..7c6b5f2136f357a17fc2ee0b09db00b57f124e44 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/move_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.cons/move_noexcept.pass.cpp
@@ -21,10 +21,12 @@
 
 #include "MoveOnly.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::priority_queue<MoveOnly> C;
         static_assert(std::is_nothrow_move_constructible<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/emplace.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/emplace.pass.cpp
index 5e5dd9f126d9de921a96573ea57035ef4e9cac20..928533075d02112dcf35cec5fbe0ba50b1efd63f 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/emplace.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/emplace.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "../../../Emplaceable.h"
 
-int main()
+int main(int, char**)
 {
     std::priority_queue<Emplaceable> q;
     q.emplace(1, 2.5);
@@ -28,4 +28,6 @@ int main()
     assert(q.top() == Emplaceable(3, 4.5));
     q.emplace(2, 3.5);
     assert(q.top() == Emplaceable(3, 4.5));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/empty.fail.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/empty.fail.cpp
index 33b97d533766dd1104b7033b9d8bd035799d94c8..698553d33e10f547c68852c92846e5560ace8c03 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/empty.fail.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/empty.fail.cpp
@@ -20,8 +20,10 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     std::priority_queue<int> c;
     c.empty();  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/empty.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/empty.pass.cpp
index 60499b853d1d0895c489a16878e4dae32f6cc975..f8f9279d576c69307b53a71319c2ae4611dd611e 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/empty.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/empty.pass.cpp
@@ -15,7 +15,7 @@
 #include <queue>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::priority_queue<int> q;
     assert(q.empty());
@@ -23,4 +23,6 @@ int main()
     assert(!q.empty());
     q.pop();
     assert(q.empty());
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/pop.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/pop.pass.cpp
index b6bcb4a72f83d65eb43c5b53240d4653bac56e30..a6fc9509c8bcf5fcde2a43ef786fa21bf97e182f 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/pop.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/pop.pass.cpp
@@ -15,7 +15,7 @@
 #include <queue>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::priority_queue<int> q;
     q.push(1);
@@ -30,4 +30,6 @@ int main()
     assert(q.top() == 1);
     q.pop();
     assert(q.empty());
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/push.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/push.pass.cpp
index 8edbe1ad1274ef17a7561d4e743760fd6d699b5d..01c0ab61832a37605eab65e249c5338bc2945f16 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/push.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/push.pass.cpp
@@ -15,7 +15,7 @@
 #include <queue>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::priority_queue<int> q;
     q.push(1);
@@ -24,4 +24,6 @@ int main()
     assert(q.top() == 3);
     q.push(2);
     assert(q.top() == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/push_rvalue.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/push_rvalue.pass.cpp
index 00bdf0c7e4cbd37c543f1cac0cd5d1940c6e156a..cf474dec565529a077a0ea7343b1e674093cf92a 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/push_rvalue.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/push_rvalue.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "MoveOnly.h"
 
-int main()
+int main(int, char**)
 {
     std::priority_queue<MoveOnly> q;
     q.push(1);
@@ -28,4 +28,6 @@ int main()
     assert(q.top() == 3);
     q.push(2);
     assert(q.top() == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/size.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/size.pass.cpp
index 51eef9eda27b48510ff8e9bc7ed5fb651edf8f22..393a97c28a418196301b6d7835b2c00334a9fc2d 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/size.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/size.pass.cpp
@@ -15,7 +15,7 @@
 #include <queue>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::priority_queue<int> q;
     assert(q.size() == 0);
@@ -23,4 +23,6 @@ int main()
     assert(q.size() == 1);
     q.pop();
     assert(q.size() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/swap.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/swap.pass.cpp
index 995e1742a5283f00ad7e8cedc0917f412f41f8a6..bc3f453d886aba128ba265ee69b9f359a0fa2c5f 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/swap.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/swap.pass.cpp
@@ -15,7 +15,7 @@
 #include <queue>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::priority_queue<int> q1;
     std::priority_queue<int> q2;
@@ -26,4 +26,6 @@ int main()
     assert(q1.empty());
     assert(q2.size() == 3);
     assert(q2.top() == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/top.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/top.pass.cpp
index 22a8174b34fc6bfc543da2c374006e3582e4aaa2..ea0e489f61704911a70a9b03e66b01741dcbde0b 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/top.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.members/top.pass.cpp
@@ -15,7 +15,7 @@
 #include <queue>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::priority_queue<int> q;
     q.push(1);
@@ -24,4 +24,6 @@ int main()
     assert(q.top() == 3);
     q.push(2);
     assert(q.top() == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.special/swap.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.special/swap.pass.cpp
index 2c9a39f66b0ea1a2f78f0d958c3c0a597642850c..bc75df0d384e1286c034248912b7b4e268216492 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.special/swap.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.special/swap.pass.cpp
@@ -17,7 +17,7 @@
 #include <queue>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::priority_queue<int> q1;
     std::priority_queue<int> q2;
@@ -28,4 +28,6 @@ int main()
     assert(q1.empty());
     assert(q2.size() == 3);
     assert(q2.top() == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.special/swap_noexcept.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.special/swap_noexcept.pass.cpp
index f2194ccf8745ba9eebcf0660c2f7dfb4d6a3e84d..ad4254c2b79f01408898906a263cc212d5332b02 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.special/swap_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/priqueue.special/swap_noexcept.pass.cpp
@@ -22,10 +22,12 @@
 
 #include "MoveOnly.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::priority_queue<MoveOnly> C;
         static_assert(noexcept(swap(std::declval<C&>(), std::declval<C&>())), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/types.fail.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/types.fail.cpp
index 431a4d0d502bddda93d2d5514f08843eca14ef64..244028e444d3aa48ac2070296a2b66f4fa8b8fb9 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/types.fail.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/types.fail.cpp
@@ -27,8 +27,10 @@
 #include <cassert>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
 //  LWG#2566 says that the first template param must match the second one's value type
     std::priority_queue<double, std::deque<int>> t;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/priority.queue/types.pass.cpp b/libcxx/test/std/containers/container.adaptors/priority.queue/types.pass.cpp
index 6084e59069e62bc99a5d188b87c15c2cf3b714f6..54712819050178b76de8a270968194d376b8192a 100644
--- a/libcxx/test/std/containers/container.adaptors/priority.queue/types.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/priority.queue/types.pass.cpp
@@ -50,7 +50,7 @@ struct C
     typedef int size_type;
 };
 
-int main()
+int main(int, char**)
 {
     static_assert(( std::is_same<std::priority_queue<int>::container_type, std::vector<int> >::value), "");
     static_assert(( std::is_same<std::priority_queue<int, std::deque<int> >::container_type, std::deque<int> >::value), "");
@@ -64,4 +64,6 @@ int main()
     static_assert(( std::uses_allocator<std::priority_queue<int>, std::allocator<int> >::value), "");
     static_assert((!std::uses_allocator<std::priority_queue<int, C>, std::allocator<int> >::value), "");
     test t;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.cons.alloc/ctor_alloc.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.cons.alloc/ctor_alloc.pass.cpp
index d2a85a34847e79e9f14dfd71fbe981203f575007..8d916f767718aa96c43aa3d2a045aaa55da81e6a 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.cons.alloc/ctor_alloc.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.cons.alloc/ctor_alloc.pass.cpp
@@ -31,8 +31,10 @@ struct test
     test_allocator<int> get_allocator() {return c.get_allocator();}
 };
 
-int main()
+int main(int, char**)
 {
     test q(test_allocator<int>(3));
     assert(q.get_allocator() == test_allocator<int>(3));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.cons.alloc/ctor_container_alloc.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.cons.alloc/ctor_container_alloc.pass.cpp
index fc3549d2da2afd267695d8b8c8207dd0eff093cc..56272064fc22fdf30d79f8beda192b3a59081cce 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.cons.alloc/ctor_container_alloc.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.cons.alloc/ctor_container_alloc.pass.cpp
@@ -44,7 +44,7 @@ struct test
     test_allocator<int> get_allocator() {return c.get_allocator();}
 };
 
-int main()
+int main(int, char**)
 {
     C d = make<C>(5);
     test q(d, test_allocator<int>(4));
@@ -55,4 +55,6 @@ int main()
         assert(q.front() == d[i]);
         q.pop();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.cons.alloc/ctor_queue_alloc.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.cons.alloc/ctor_queue_alloc.pass.cpp
index 6c7fbbc8110a8b269a50e467ac1cbadc54a4bcd5..8a66c6f12e7e4e1c615fcd7388f89882e799e778 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.cons.alloc/ctor_queue_alloc.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.cons.alloc/ctor_queue_alloc.pass.cpp
@@ -42,10 +42,12 @@ struct test
     allocator_type get_allocator() {return this->c.get_allocator();}
 };
 
-int main()
+int main(int, char**)
 {
     test<int> q(make<C>(5), test_allocator<int>(4));
     test<int> q2(q, test_allocator<int>(5));
     assert(q2.get_allocator() == test_allocator<int>(5));
     assert(q2.size() == 5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.cons.alloc/ctor_rcontainer_alloc.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.cons.alloc/ctor_rcontainer_alloc.pass.cpp
index cc6cb5cdbc91cd10e16080e9a0ea0541e47dc2a5..3af4fb0dacc445e89a3e61ecdbff784d8bcd1348 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.cons.alloc/ctor_rcontainer_alloc.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.cons.alloc/ctor_rcontainer_alloc.pass.cpp
@@ -48,9 +48,11 @@ struct test
 };
 
 
-int main()
+int main(int, char**)
 {
     test<MoveOnly> q(make<C>(5), test_allocator<MoveOnly>(4));
     assert(q.get_allocator() == test_allocator<MoveOnly>(4));
     assert(q.size() == 5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.cons.alloc/ctor_rqueue_alloc.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.cons.alloc/ctor_rqueue_alloc.pass.cpp
index cac8bf3cd1f75845422fe5dbdff4d438addfa1ad..29a742df7d41c80bd2d493ab84a2acdcd9d89633 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.cons.alloc/ctor_rqueue_alloc.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.cons.alloc/ctor_rqueue_alloc.pass.cpp
@@ -48,10 +48,12 @@ struct test
 };
 
 
-int main()
+int main(int, char**)
 {
     test<MoveOnly> q(make<C>(5), test_allocator<MoveOnly>(4));
     test<MoveOnly> q2(std::move(q), test_allocator<MoveOnly>(5));
     assert(q2.get_allocator() == test_allocator<MoveOnly>(5));
     assert(q2.size() == 5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.cons/ctor_container.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.cons/ctor_container.pass.cpp
index e9c41a0b612df9876257011579b1c014339f77bf..dad35d2d1696a037940fb150f62fddcc61980b26 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.cons/ctor_container.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.cons/ctor_container.pass.cpp
@@ -24,7 +24,7 @@ make(int n)
     return c;
 }
 
-int main()
+int main(int, char**)
 {
     std::deque<int> d = make<std::deque<int> >(5);
     std::queue<int> q(d);
@@ -34,4 +34,6 @@ int main()
         assert(q.front() == d[i]);
         q.pop();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.cons/ctor_copy.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.cons/ctor_copy.pass.cpp
index 35c2fa0136eafcedae3db042a6de710517f270c8..19e46a23662e5e8034e501113b18694c7de52014 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.cons/ctor_copy.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.cons/ctor_copy.pass.cpp
@@ -23,9 +23,11 @@ make(int n)
     return c;
 }
 
-int main()
+int main(int, char**)
 {
     std::queue<int> q(make<std::deque<int> >(5));
     std::queue<int> q2 = q;
     assert(q2 == q);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.cons/ctor_default.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.cons/ctor_default.pass.cpp
index 0a1d3dd960b1815abd924c58cb970f251889bb72..c5c8b17a6901e08c29d903dd0f3cd337f98ab4bd 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.cons/ctor_default.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.cons/ctor_default.pass.cpp
@@ -15,7 +15,7 @@
 
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     std::queue<int, std::vector<int, limited_allocator<int, 10> > > q;
     assert(q.size() == 0);
@@ -24,4 +24,6 @@ int main()
     assert(q.size() == 2);
     assert(q.front() == 1);
     assert(q.back() == 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.cons/ctor_move.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.cons/ctor_move.pass.cpp
index a9def3e333ba0d78ac1bf97ed3bd65e79940a442..c275d5d602f8b6a0bc65bbe6ad0c61aec99afd56 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.cons/ctor_move.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.cons/ctor_move.pass.cpp
@@ -29,10 +29,12 @@ make(int n)
 }
 
 
-int main()
+int main(int, char**)
 {
     std::queue<MoveOnly> q(make<std::deque<MoveOnly> >(5));
     std::queue<MoveOnly> q2 = std::move(q);
     assert(q2.size() == 5);
     assert(q.empty());
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.cons/ctor_rcontainer.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.cons/ctor_rcontainer.pass.cpp
index 00aba51c3c7da3f69987e01417a1c57c71e3eb9d..3812ce9169b5db933dffe7a0156ca55f1af0ccda 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.cons/ctor_rcontainer.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.cons/ctor_rcontainer.pass.cpp
@@ -29,8 +29,10 @@ make(int n)
 }
 
 
-int main()
+int main(int, char**)
 {
     std::queue<MoveOnly> q(make<std::deque<MoveOnly> >(5));
     assert(q.size() == 5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.cons/deduct.fail.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.cons/deduct.fail.cpp
index eecb0343b4c7fe3af70b90dc5951aa975afde1b3..00b39c6a95b12653013a553ea9d07753add7a0eb 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.cons/deduct.fail.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.cons/deduct.fail.cpp
@@ -17,7 +17,7 @@
 #include <cstddef>
 
 
-int main()
+int main(int, char**)
 {
 //  Test the explicit deduction guides
     {
@@ -42,4 +42,6 @@ int main()
 //      stack<allocator<int>, allocator<allocator<int>>>
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.cons/deduct.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.cons/deduct.pass.cpp
index 45a6f2e75a28eefd754c65098427f41d907ccdc2..247da2a3d98fecd9e613d1b3de3bc3f57024e147 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.cons/deduct.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.cons/deduct.pass.cpp
@@ -33,7 +33,7 @@
 
 struct A {};
 
-int main()
+int main(int, char**)
 {
 
 //  Test the explicit deduction guides
@@ -87,4 +87,6 @@ int main()
     assert(que.back() == 3);
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.cons/default_noexcept.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.cons/default_noexcept.pass.cpp
index a53dd9492564b6dadbea83d77ab6537186ae05f6..1200f2e2fef2732d400f40e3af0b5ffb92ce2783 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.cons/default_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.cons/default_noexcept.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_macros.h"
 #include "MoveOnly.h"
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -29,4 +29,6 @@ int main()
         static_assert(std::is_nothrow_default_constructible<C>::value, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.cons/dtor_noexcept.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.cons/dtor_noexcept.pass.cpp
index 4c87d15e04760a5110e9c9eeb95e5d0f77de942e..18e42ea3a7edaaa525c0d9b1ad8dd98af4e7e701 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.cons/dtor_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.cons/dtor_noexcept.pass.cpp
@@ -17,10 +17,12 @@
 
 #include "MoveOnly.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::queue<MoveOnly> C;
         static_assert(std::is_nothrow_destructible<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.cons/move_assign_noexcept.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.cons/move_assign_noexcept.pass.cpp
index 93f69059fb3145914d960b94eeb12bae0cfe893a..a82ab8fa41c7cafae348ad054936182b087883b3 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.cons/move_assign_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.cons/move_assign_noexcept.pass.cpp
@@ -20,10 +20,12 @@
 
 #include "MoveOnly.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::queue<MoveOnly> C;
         static_assert(std::is_nothrow_move_assignable<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.cons/move_noexcept.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.cons/move_noexcept.pass.cpp
index 24e96edc5e496ee5821ac70cdefac483ce173ed8..e4c170a8bb9d6e377d7b96170b0591b568f6e23e 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.cons/move_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.cons/move_noexcept.pass.cpp
@@ -22,7 +22,7 @@
 #include "test_macros.h"
 #include "MoveOnly.h"
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -30,4 +30,6 @@ int main()
         static_assert(std::is_nothrow_move_constructible<C>::value, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/assign_copy.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/assign_copy.pass.cpp
index 5fe6b70c64dca3290f89fa99bac0fe3bf254b583..98385a6f7cc3e29d51f3f84444ee1d28d91f6704 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/assign_copy.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/assign_copy.pass.cpp
@@ -23,10 +23,12 @@ make(int n)
     return c;
 }
 
-int main()
+int main(int, char**)
 {
     std::queue<int> q(make<std::deque<int> >(5));
     std::queue<int> q2;
     q2 = q;
     assert(q2 == q);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/assign_move.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/assign_move.pass.cpp
index 87c9ad197e651f02ad252b29e2e84c6d7b40633e..de30e5cfe2ebcc39a00f79f8a03ce4110dc092d0 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/assign_move.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/assign_move.pass.cpp
@@ -29,11 +29,13 @@ make(int n)
 }
 
 
-int main()
+int main(int, char**)
 {
     std::queue<MoveOnly> q(make<std::deque<MoveOnly> >(5));
     std::queue<MoveOnly> q2;
     q2 = std::move(q);
     assert(q2.size() == 5);
     assert(q.empty());
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/back.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/back.pass.cpp
index 115360e0709dfb1466ffd19d1e49fe3a5be467f8..cb115c7022294be97975542d772d731fdacb99b5 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/back.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/back.pass.cpp
@@ -13,7 +13,7 @@
 #include <queue>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::queue<int> q;
     assert(q.size() == 0);
@@ -22,4 +22,6 @@ int main()
     q.push(3);
     int& ir = q.back();
     assert(ir == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/back_const.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/back_const.pass.cpp
index 158aa83a9f0eb47a18ebb839dd0bfd9eac12dabe..3a6e4c890372f6dd33b163569b183768a25ef80a 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/back_const.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/back_const.pass.cpp
@@ -13,7 +13,7 @@
 #include <queue>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::queue<int> q;
     assert(q.size() == 0);
@@ -23,4 +23,6 @@ int main()
     const std::queue<int>& cqr = q;
     const int& cir = cqr.back();
     assert(cir == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/emplace.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/emplace.pass.cpp
index a8e8791ac6982d970750e584df33d4cab3cb4a27..74afcce974fa61bdf12395c93a844fbd1f1ef133 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/emplace.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/emplace.pass.cpp
@@ -37,7 +37,7 @@ void test_return_type() {
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test_return_type<std::queue<int> > ();
     test_return_type<std::queue<int, std::list<int> > > ();
@@ -61,4 +61,6 @@ int main()
     assert(q.size() == 3);
     assert(q.front() == Emplaceable(1, 2.5));
     assert(q.back() == Emplaceable(3, 4.5));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/empty.fail.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/empty.fail.cpp
index f53f9a805e0e3b82093d6e06e10f4f39bfe14b59..454bf32bede8ea8b4ba7925ff5c76fdbe63335ca 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/empty.fail.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/empty.fail.cpp
@@ -20,8 +20,10 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     std::queue<int> c;
     c.empty();  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/empty.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/empty.pass.cpp
index 095512c212423c151d0192c0ab23ebb0defac73c..cc0fc56b7c4ebdf01fde14c2a23b47f81225af94 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/empty.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/empty.pass.cpp
@@ -13,7 +13,7 @@
 #include <queue>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::queue<int> q;
     assert(q.empty());
@@ -21,4 +21,6 @@ int main()
     assert(!q.empty());
     q.pop();
     assert(q.empty());
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/front.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/front.pass.cpp
index 7ce29976baf1c2c2df03eb09f4faf9920ad01dca..9c8d253fb924b51f64e2d4bd05400649aaf811b8 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/front.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/front.pass.cpp
@@ -13,7 +13,7 @@
 #include <queue>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::queue<int> q;
     assert(q.size() == 0);
@@ -22,4 +22,6 @@ int main()
     q.push(3);
     int& ir = q.front();
     assert(ir == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/front_const.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/front_const.pass.cpp
index edcb21ea2242fce0cd457566f2b8233339d837fa..5ad1ae97aaec4153a8aca6113ef3f4ed761e1065 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/front_const.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/front_const.pass.cpp
@@ -13,7 +13,7 @@
 #include <queue>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::queue<int> q;
     assert(q.size() == 0);
@@ -23,4 +23,6 @@ int main()
     const std::queue<int>& cqr = q;
     const int& cir = cqr.front();
     assert(cir == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/pop.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/pop.pass.cpp
index 587cf26c3dd82523c67f61562934582e86ad7754..128cda51237237f56c2a8f6a408bc2010da32f15 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/pop.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/pop.pass.cpp
@@ -13,7 +13,7 @@
 #include <queue>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::queue<int> q;
     assert(q.size() == 0);
@@ -33,4 +33,6 @@ int main()
     assert(q.back() == 3);
     q.pop();
     assert(q.size() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/push.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/push.pass.cpp
index a9e962f8afe3e6ccb812c34423aff45c58e19cc7..b2a784ccfa8566a408e300d5c981fbbe6f06494c 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/push.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/push.pass.cpp
@@ -13,7 +13,7 @@
 #include <queue>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::queue<int> q;
     q.push(1);
@@ -28,4 +28,6 @@ int main()
     assert(q.size() == 3);
     assert(q.front() == 1);
     assert(q.back() == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/push_rv.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/push_rv.pass.cpp
index aafc9563525ceeda83b8ca302c79c7c6bd0d00dc..17c442b151efe17b1f8553b26df0d99725b79b70 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/push_rv.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/push_rv.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "MoveOnly.h"
 
-int main()
+int main(int, char**)
 {
     std::queue<MoveOnly> q;
     q.push(MoveOnly(1));
@@ -32,4 +32,6 @@ int main()
     assert(q.size() == 3);
     assert(q.front() == MoveOnly(1));
     assert(q.back() == MoveOnly(3));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/size.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/size.pass.cpp
index f3ecaa5c4f7ae5482a5f4702b8ff4a8294b98226..fb4fdfcac4d828751fb18b2ae404d76a1e08cbf3 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/size.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/size.pass.cpp
@@ -13,10 +13,12 @@
 #include <queue>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::queue<int> q;
     assert(q.size() == 0);
     q.push(1);
     assert(q.size() == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/swap.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/swap.pass.cpp
index 9017d21273d5975c062c4b95fb14b458edee0596..3635cea4a91aeb311de91e24f265c2eec6086651 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/swap.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/swap.pass.cpp
@@ -23,7 +23,7 @@ make(int n)
     return c;
 }
 
-int main()
+int main(int, char**)
 {
     std::queue<int> q1 = make<std::queue<int> >(5);
     std::queue<int> q2 = make<std::queue<int> >(10);
@@ -32,4 +32,6 @@ int main()
     q1.swap(q2);
     assert(q1 == q2_save);
     assert(q2 == q1_save);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/types.fail.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/types.fail.cpp
index b9e018ca13ac54dfbd994f26a04673cba91b74ee..041008ce6aa20256aa6ecb6a5253d43972296af6 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/types.fail.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/types.fail.cpp
@@ -12,8 +12,10 @@
 #include <cassert>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
 //  LWG#2566 says that the first template param must match the second one's value type
     std::queue<double, std::deque<int>> t;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/types.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/types.pass.cpp
index edc41c1a3522ed893c8c446644b7c7f6cf10d876..8623710eaa21015248f9e5673cb7c82f3c42be0e 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/types.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/types.pass.cpp
@@ -43,7 +43,7 @@ struct C
     typedef int size_type;
 };
 
-int main()
+int main(int, char**)
 {
     static_assert(( std::is_same<std::queue<int>::container_type, std::deque<int> >::value), "");
     static_assert(( std::is_same<std::queue<int, std::vector<int> >::container_type, std::vector<int> >::value), "");
@@ -54,4 +54,6 @@ int main()
     static_assert(( std::uses_allocator<std::queue<int>, std::allocator<int> >::value), "");
     static_assert((!std::uses_allocator<std::queue<int, C>, std::allocator<int> >::value), "");
     test t;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.ops/eq.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.ops/eq.pass.cpp
index ee36779b5bd26f91dbc29b39369361ca2d78d304..b4a3327d86b9a9593ec8a89491c6015cbf880f15 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.ops/eq.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.ops/eq.pass.cpp
@@ -27,7 +27,7 @@ make(int n)
     return c;
 }
 
-int main()
+int main(int, char**)
 {
     std::queue<int> q1 = make<std::queue<int> >(5);
     std::queue<int> q2 = make<std::queue<int> >(10);
@@ -36,4 +36,6 @@ int main()
     assert(q1 == q1_save);
     assert(q1 != q2);
     assert(q2 == q2_save);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.ops/lt.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.ops/lt.pass.cpp
index 66ef66c7bd46c556e2ecb2558c891455f4bbf5c6..a8eeb1be19747cd33b9a6925a85f62c92e73309a 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.ops/lt.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.ops/lt.pass.cpp
@@ -33,7 +33,7 @@ make(int n)
     return c;
 }
 
-int main()
+int main(int, char**)
 {
     std::queue<int> q1 = make<std::queue<int> >(5);
     std::queue<int> q2 = make<std::queue<int> >(10);
@@ -41,4 +41,6 @@ int main()
     assert(q2 > q1);
     assert(q1 <= q2);
     assert(q2 >= q1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.special/swap.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.special/swap.pass.cpp
index fcaec66d7559a72dd789eff748c484c1328b04fd..1adc4f1f474ee478b57ac25c9de9509603b4bbf5 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.special/swap.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.special/swap.pass.cpp
@@ -24,7 +24,7 @@ make(int n)
     return c;
 }
 
-int main()
+int main(int, char**)
 {
     std::queue<int> q1 = make<std::queue<int> >(5);
     std::queue<int> q2 = make<std::queue<int> >(10);
@@ -33,4 +33,6 @@ int main()
     swap(q1, q2);
     assert(q1 == q2_save);
     assert(q2 == q1_save);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.special/swap_noexcept.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.special/swap_noexcept.pass.cpp
index 81d728a27d6f6b691f2372379c4359ceed86ad43..b8cc387d186b2582e4118508e393924fd2803075 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.special/swap_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.special/swap_noexcept.pass.cpp
@@ -21,10 +21,12 @@
 
 #include "MoveOnly.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::queue<MoveOnly> C;
         static_assert(noexcept(swap(std::declval<C&>(), std::declval<C&>())), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.cons.alloc/ctor_alloc.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.cons.alloc/ctor_alloc.pass.cpp
index c0023c401387a19edc06c15223b4e297f87962f7..9fb09b158dfbcf247117733a5a11ae7928a49a21 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.cons.alloc/ctor_alloc.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.cons.alloc/ctor_alloc.pass.cpp
@@ -31,8 +31,10 @@ struct test
     test_allocator<int> get_allocator() {return c.get_allocator();}
 };
 
-int main()
+int main(int, char**)
 {
     test q(test_allocator<int>(3));
     assert(q.get_allocator() == test_allocator<int>(3));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.cons.alloc/ctor_container_alloc.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.cons.alloc/ctor_container_alloc.pass.cpp
index ef4d25e05e9f5b6d076294cca0d2e5cf795b9194..b0c6f4fcac792788008426e403d9078cd9b0119b 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.cons.alloc/ctor_container_alloc.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.cons.alloc/ctor_container_alloc.pass.cpp
@@ -44,7 +44,7 @@ struct test
     test_allocator<int> get_allocator() {return c.get_allocator();}
 };
 
-int main()
+int main(int, char**)
 {
     C d = make<C>(5);
     test q(d, test_allocator<int>(4));
@@ -55,4 +55,6 @@ int main()
         assert(q.top() == d[d.size() - i - 1]);
         q.pop();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.cons.alloc/ctor_copy_alloc.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.cons.alloc/ctor_copy_alloc.pass.cpp
index f7c0a962021a43c19d03e540c61d0fe0a1fc0b76..0d8481228fd8de3ce8e7e3ff1ca025aa4c0e9774 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.cons.alloc/ctor_copy_alloc.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.cons.alloc/ctor_copy_alloc.pass.cpp
@@ -42,10 +42,12 @@ struct test
     allocator_type get_allocator() {return this->c.get_allocator();}
 };
 
-int main()
+int main(int, char**)
 {
     test<int> q(make<C>(5), test_allocator<int>(4));
     test<int> q2(q, test_allocator<int>(5));
     assert(q2.get_allocator() == test_allocator<int>(5));
     assert(q2.size() == 5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.cons.alloc/ctor_rcontainer_alloc.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.cons.alloc/ctor_rcontainer_alloc.pass.cpp
index f33f638b8e5ed51ca9c1762cf7002776fa2feea0..5181c673916c43db2158032b87c7c985bb3e5e8e 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.cons.alloc/ctor_rcontainer_alloc.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.cons.alloc/ctor_rcontainer_alloc.pass.cpp
@@ -48,9 +48,11 @@ struct test
 };
 
 
-int main()
+int main(int, char**)
 {
     test<MoveOnly> q(make<C>(5), test_allocator<MoveOnly>(4));
     assert(q.get_allocator() == test_allocator<MoveOnly>(4));
     assert(q.size() == 5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.cons.alloc/ctor_rqueue_alloc.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.cons.alloc/ctor_rqueue_alloc.pass.cpp
index 2889763ecf0891231e87eb76c11c023d293f479e..c5ff35d2d7a72501f17589fb8bed49cec795cb86 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.cons.alloc/ctor_rqueue_alloc.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.cons.alloc/ctor_rqueue_alloc.pass.cpp
@@ -48,10 +48,12 @@ struct test
 };
 
 
-int main()
+int main(int, char**)
 {
     test<MoveOnly> q(make<C>(5), test_allocator<MoveOnly>(4));
     test<MoveOnly> q2(std::move(q), test_allocator<MoveOnly>(5));
     assert(q2.get_allocator() == test_allocator<MoveOnly>(5));
     assert(q2.size() == 5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.cons/ctor_container.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.cons/ctor_container.pass.cpp
index 7db358b3f0dbf9a11ef6270d2f3697badcd4613e..c649e238f5bf3d03399932f2d167dda373f691cb 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.cons/ctor_container.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.cons/ctor_container.pass.cpp
@@ -24,7 +24,7 @@ make(int n)
     return c;
 }
 
-int main()
+int main(int, char**)
 {
     std::deque<int> d = make<std::deque<int> >(5);
     std::stack<int> q(d);
@@ -34,4 +34,6 @@ int main()
         assert(q.top() == d[d.size() - i - 1]);
         q.pop();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.cons/ctor_copy.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.cons/ctor_copy.pass.cpp
index 2bbf7cc93c9ecfbbf6a51215f0f9ee21916055c8..ef3606366ffeb087649bbbdc0f2bb36e7bdfa644 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.cons/ctor_copy.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.cons/ctor_copy.pass.cpp
@@ -23,9 +23,11 @@ make(int n)
     return c;
 }
 
-int main()
+int main(int, char**)
 {
     std::stack<int> q(make<std::deque<int> >(5));
     std::stack<int> q2 = q;
     assert(q2 == q);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.cons/ctor_default.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.cons/ctor_default.pass.cpp
index 731b2fe4ec744022f538595a9fb053d45ee10bda..460cf27ec843f027ee2ef0f08ac7d7bc553979df 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.cons/ctor_default.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.cons/ctor_default.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     std::stack<int, std::vector<int, limited_allocator<int, 10> > > q;
     assert(q.size() == 0);
@@ -24,4 +24,6 @@ int main()
     q.push(2);
     assert(q.size() == 2);
     assert(q.top() == 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.cons/ctor_move.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.cons/ctor_move.pass.cpp
index e5c846df17387a6513e72b5f14b51bc7e776df56..86f4414c91e32a62b42eaf2ab9572ee9c718a237 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.cons/ctor_move.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.cons/ctor_move.pass.cpp
@@ -29,10 +29,12 @@ make(int n)
 }
 
 
-int main()
+int main(int, char**)
 {
     std::stack<MoveOnly> q(make<std::deque<MoveOnly> >(5));
     std::stack<MoveOnly> q2 = std::move(q);
     assert(q2.size() == 5);
     assert(q.empty());
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.cons/ctor_rcontainer.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.cons/ctor_rcontainer.pass.cpp
index 9ead91521666842919c399cd4967baed663ef17e..28fb5655f94f78685f0ce44b123ba9ae87d1a662 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.cons/ctor_rcontainer.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.cons/ctor_rcontainer.pass.cpp
@@ -29,8 +29,10 @@ make(int n)
 }
 
 
-int main()
+int main(int, char**)
 {
     std::stack<MoveOnly> q(make<std::deque<MoveOnly> >(5));
     assert(q.size() == 5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.cons/deduct.fail.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.cons/deduct.fail.cpp
index bfddd8b598c86ca0d4039f443d5fb877e360afdd..894906fc43f4e7c21e818cea4f51ebb3ddc736b9 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.cons/deduct.fail.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.cons/deduct.fail.cpp
@@ -24,7 +24,7 @@
 #include <cstddef>
 
 
-int main()
+int main(int, char**)
 {
 //  Test the explicit deduction guides
     {
@@ -49,4 +49,6 @@ int main()
 //      stack<allocator<int>, allocator<allocator<int>>>
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.cons/deduct.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.cons/deduct.pass.cpp
index ec724b063b530dc4b6ac5ae026398e27aa696a72..dd5ab91a09c9acce3f08e2873c6a6b3ec7b486be 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.cons/deduct.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.cons/deduct.pass.cpp
@@ -35,7 +35,7 @@
 
 struct A {};
 
-int main()
+int main(int, char**)
 {
 
 //  Test the explicit deduction guides
@@ -90,4 +90,6 @@ int main()
     assert(stk.top() == 3);
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.cons/default_noexcept.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.cons/default_noexcept.pass.cpp
index 2e901843ef7769b0469b07c94ba2612cc13a903b..d06e2865e8aef9a506252141e9bef18509f7e3e3 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.cons/default_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.cons/default_noexcept.pass.cpp
@@ -22,7 +22,7 @@
 #include "test_macros.h"
 #include "MoveOnly.h"
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -30,4 +30,6 @@ int main()
         static_assert(std::is_nothrow_default_constructible<C>::value, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.cons/dtor_noexcept.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.cons/dtor_noexcept.pass.cpp
index 616f464186e8e5d6246425b3463ffb42e269fe9b..7c5fd648684e70fbd94a454c6870358ed772d885 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.cons/dtor_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.cons/dtor_noexcept.pass.cpp
@@ -17,10 +17,12 @@
 
 #include "MoveOnly.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::stack<MoveOnly> C;
         static_assert(std::is_nothrow_destructible<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.cons/move_assign_noexcept.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.cons/move_assign_noexcept.pass.cpp
index 0e97c0ff66df4528701a2ed88b075e43fb7f33f2..6ed6b8250aa3833343477d432286ac4d8a727880 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.cons/move_assign_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.cons/move_assign_noexcept.pass.cpp
@@ -20,10 +20,12 @@
 
 #include "MoveOnly.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::stack<MoveOnly> C;
         static_assert(std::is_nothrow_move_assignable<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.cons/move_noexcept.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.cons/move_noexcept.pass.cpp
index e7743ad9807706608e221c2631b4ba214ad6bf01..ddf07c42468d8ed672f840d3e4e23eab64643cb7 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.cons/move_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.cons/move_noexcept.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_macros.h"
 #include "MoveOnly.h"
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -29,4 +29,6 @@ int main()
         static_assert(std::is_nothrow_move_constructible<C>::value, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/assign_copy.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/assign_copy.pass.cpp
index 0f8bf035d98000ff88c3e5721df33c05e698b5d1..df34e4c63c8796daa791749769c258c70cabfc53 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/assign_copy.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/assign_copy.pass.cpp
@@ -23,10 +23,12 @@ make(int n)
     return c;
 }
 
-int main()
+int main(int, char**)
 {
     std::stack<int> q(make<std::deque<int> >(5));
     std::stack<int> q2;
     q2 = q;
     assert(q2 == q);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/assign_move.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/assign_move.pass.cpp
index 16609e983bee3b67d58275a5ef23ff49f6d2bc99..ad77defe21434b7fd7834b28018a24750e88a12c 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/assign_move.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/assign_move.pass.cpp
@@ -29,11 +29,13 @@ make(int n)
 }
 
 
-int main()
+int main(int, char**)
 {
     std::stack<MoveOnly> q(make<std::deque<MoveOnly> >(5));
     std::stack<MoveOnly> q2;
     q2 = std::move(q);
     assert(q2.size() == 5);
     assert(q.empty());
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/emplace.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/emplace.pass.cpp
index 605440bc48f0211f6f85946bbc8032a28434556c..1aa6b62c7bb4588b3029a4717638f95a4c8f9323 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/emplace.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/emplace.pass.cpp
@@ -36,7 +36,7 @@ void test_return_type() {
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test_return_type<std::stack<int> > ();
     test_return_type<std::stack<int, std::vector<int> > > ();
@@ -57,4 +57,6 @@ int main()
 #endif
     assert(q.size() == 3);
     assert(q.top() == Emplaceable(3, 4.5));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/empty.fail.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/empty.fail.cpp
index afdd996ad7005be2dfc6e4ae51b993371cfb57a4..54cd986295a68faa8eb7d3fc9ef26c4feb0b8712 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/empty.fail.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/empty.fail.cpp
@@ -20,8 +20,10 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     std::stack<int> c;
     c.empty();  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/empty.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/empty.pass.cpp
index 37bf18e2d63538b7b0855c4fc5191f60650a5330..a51045e613df541bcd5c0180ef9dea22e4f60ed8 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/empty.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/empty.pass.cpp
@@ -13,7 +13,7 @@
 #include <stack>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::stack<int> q;
     assert(q.empty());
@@ -21,4 +21,6 @@ int main()
     assert(!q.empty());
     q.pop();
     assert(q.empty());
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/pop.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/pop.pass.cpp
index 756eb01c033e072d506dc24a76a24ac209ebebb5..95472d7e2c6b292122c23e4dab6d363b4371418f 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/pop.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/pop.pass.cpp
@@ -13,7 +13,7 @@
 #include <stack>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::stack<int> q;
     assert(q.size() == 0);
@@ -30,4 +30,6 @@ int main()
     assert(q.top() == 1);
     q.pop();
     assert(q.size() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/push.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/push.pass.cpp
index 19615a031dd74c5dcb638992202357329cb137d3..70c085f17dd4ead6ef19542dfa18d02389401a70 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/push.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/push.pass.cpp
@@ -13,7 +13,7 @@
 #include <stack>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::stack<int> q;
     q.push(1);
@@ -25,4 +25,6 @@ int main()
     q.push(3);
     assert(q.size() == 3);
     assert(q.top() == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/push_rv.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/push_rv.pass.cpp
index f8ad69e99d608a8dbadcab16e26c6c734e613a1d..8969d237b54c454bb3166744667594afdd883cab 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/push_rv.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/push_rv.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "MoveOnly.h"
 
-int main()
+int main(int, char**)
 {
     std::stack<MoveOnly> q;
     q.push(MoveOnly(1));
@@ -29,4 +29,6 @@ int main()
     q.push(MoveOnly(3));
     assert(q.size() == 3);
     assert(q.top() == MoveOnly(3));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/size.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/size.pass.cpp
index 2e2f945b23d19d7263812353a402c5f8fd32d345..26f2e22ee8eacfff2bc8ea7d78d59c6203e7d5c2 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/size.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/size.pass.cpp
@@ -13,10 +13,12 @@
 #include <stack>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::stack<int> q;
     assert(q.size() == 0);
     q.push(1);
     assert(q.size() == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/swap.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/swap.pass.cpp
index 10c44c0df3d3db52021a2071391c45e2e084267b..88ec3cdfe3d286c1ee406e5565369f2fa71df60e 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/swap.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/swap.pass.cpp
@@ -23,7 +23,7 @@ make(int n)
     return c;
 }
 
-int main()
+int main(int, char**)
 {
     std::stack<int> q1 = make<std::stack<int> >(5);
     std::stack<int> q2 = make<std::stack<int> >(10);
@@ -32,4 +32,6 @@ int main()
     q1.swap(q2);
     assert(q1 == q2_save);
     assert(q2 == q1_save);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/top.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/top.pass.cpp
index f58effe196e900eb5660c28a07be96de70381fd9..6923cc9d27be234c2d570f348cb6e6e11061f4bc 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/top.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/top.pass.cpp
@@ -13,7 +13,7 @@
 #include <stack>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::stack<int> q;
     assert(q.size() == 0);
@@ -22,4 +22,6 @@ int main()
     q.push(3);
     int& ir = q.top();
     assert(ir == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/top_const.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/top_const.pass.cpp
index 348946baa6b2b348a90436beb7d1d9026758e996..a5e8c49fa203f0e388098de762f83fe293758216 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/top_const.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/top_const.pass.cpp
@@ -13,7 +13,7 @@
 #include <stack>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::stack<int> q;
     assert(q.size() == 0);
@@ -23,4 +23,6 @@ int main()
     const std::stack<int>& cqr = q;
     const int& cir = cqr.top();
     assert(cir == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/types.fail.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/types.fail.cpp
index f343fa109d3be7c4dee6d2615e913e2d77dfbd79..d5fe97fd5d75f537deeb86577ab10c15031f4964 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/types.fail.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/types.fail.cpp
@@ -27,8 +27,10 @@
 #include <cassert>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
 //  LWG#2566 says that the first template param must match the second one's value type
     std::stack<double, std::deque<int>> t;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/types.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/types.pass.cpp
index 33308c1adee425db112319509337137f800efc34..55fc27f8430dcaab84671af34a4812812a6c14af 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/types.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/types.pass.cpp
@@ -44,7 +44,7 @@ struct C
     typedef int size_type;
 };
 
-int main()
+int main(int, char**)
 {
     static_assert(( std::is_same<std::stack<int>::container_type, std::deque<int> >::value), "");
     static_assert(( std::is_same<std::stack<int, std::vector<int> >::container_type, std::vector<int> >::value), "");
@@ -55,4 +55,6 @@ int main()
     static_assert(( std::uses_allocator<std::stack<int>, std::allocator<int> >::value), "");
     static_assert((!std::uses_allocator<std::stack<int, C>, std::allocator<int> >::value), "");
     test t;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.ops/eq.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.ops/eq.pass.cpp
index a6e60f1e0d1e34a93a369bf675001f2da7558a0c..306869f0e9b0b9a085adc09815af419b01a41170 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.ops/eq.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.ops/eq.pass.cpp
@@ -27,7 +27,7 @@ make(int n)
     return c;
 }
 
-int main()
+int main(int, char**)
 {
     std::stack<int> q1 = make<std::stack<int> >(5);
     std::stack<int> q2 = make<std::stack<int> >(10);
@@ -36,4 +36,6 @@ int main()
     assert(q1 == q1_save);
     assert(q1 != q2);
     assert(q2 == q2_save);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.ops/lt.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.ops/lt.pass.cpp
index 5494b3dae71b37f91926b7b45785a778835a03d9..3c8734befda21f9e750093cc656616f8a2f2fd9e 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.ops/lt.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.ops/lt.pass.cpp
@@ -33,7 +33,7 @@ make(int n)
     return c;
 }
 
-int main()
+int main(int, char**)
 {
     std::stack<int> q1 = make<std::stack<int> >(5);
     std::stack<int> q2 = make<std::stack<int> >(10);
@@ -41,4 +41,6 @@ int main()
     assert(q2 > q1);
     assert(q1 <= q2);
     assert(q2 >= q1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.special/swap.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.special/swap.pass.cpp
index f8f0ed919b85ac210dbf5329e1a9091d0913c922..cb1323b58737c51969608cf5752277ab38f16ce4 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.special/swap.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.special/swap.pass.cpp
@@ -24,7 +24,7 @@ make(int n)
     return c;
 }
 
-int main()
+int main(int, char**)
 {
     std::stack<int> q1 = make<std::stack<int> >(5);
     std::stack<int> q2 = make<std::stack<int> >(10);
@@ -33,4 +33,6 @@ int main()
     swap(q1, q2);
     assert(q1 == q2_save);
     assert(q2 == q1_save);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.special/swap_noexcept.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.special/swap_noexcept.pass.cpp
index 43195ecc8b9847e0e8030981296a1f3cbd2d300c..415ea607e17ebf9fad78edf54c5c8b302c5d7eea 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.special/swap_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.special/swap_noexcept.pass.cpp
@@ -21,10 +21,12 @@
 
 #include "MoveOnly.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::stack<MoveOnly> C;
         static_assert(noexcept(swap(std::declval<C&>(), std::declval<C&>())), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.node/node_handle.pass.cpp b/libcxx/test/std/containers/container.node/node_handle.pass.cpp
index 37bb73197af0a7155db4968236f7421905c7d505..40cd8d0499ad863eb9de09e466328838b4c29fc5 100644
--- a/libcxx/test/std/containers/container.node/node_handle.pass.cpp
+++ b/libcxx/test/std/containers/container.node/node_handle.pass.cpp
@@ -128,7 +128,7 @@ void test_insert_return_type()
     test_typedef<typename Container::insert_return_type>();
 }
 
-int main()
+int main(int, char**)
 {
     test_node_handle_operations<std::map<int, int>>();
     test_node_handle_operations_multi<std::multimap<int, int>>();
@@ -143,4 +143,6 @@ int main()
     test_insert_return_type<std::set<int>>();
     test_insert_return_type<std::unordered_map<int, int>>();
     test_insert_return_type<std::unordered_set<int>>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.requirements/associative.reqmts/associative.reqmts.except/nothing_to_do.pass.cpp b/libcxx/test/std/containers/container.requirements/associative.reqmts/associative.reqmts.except/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/containers/container.requirements/associative.reqmts/associative.reqmts.except/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/containers/container.requirements/associative.reqmts/associative.reqmts.except/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.requirements/associative.reqmts/nothing_to_do.pass.cpp b/libcxx/test/std/containers/container.requirements/associative.reqmts/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/containers/container.requirements/associative.reqmts/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/containers/container.requirements/associative.reqmts/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.requirements/container.requirements.dataraces/nothing_to_do.pass.cpp b/libcxx/test/std/containers/container.requirements/container.requirements.dataraces/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/containers/container.requirements/container.requirements.dataraces/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/containers/container.requirements/container.requirements.dataraces/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.requirements/container.requirements.general/allocator_move.pass.cpp b/libcxx/test/std/containers/container.requirements/container.requirements.general/allocator_move.pass.cpp
index 3914affd306db1c8ce87a89d2db8b8f9d3312180..98c291c2e4572a4d96b995f35e521e8f9307f20d 100644
--- a/libcxx/test/std/containers/container.requirements/container.requirements.general/allocator_move.pass.cpp
+++ b/libcxx/test/std/containers/container.requirements/container.requirements.general/allocator_move.pass.cpp
@@ -61,7 +61,7 @@ void test(int expected_num_allocs = 1) {
   }
 }
 
-int main() {
+int main(int, char**) {
   { // test sequence containers
     test<std::vector<int, test_allocator<int> > >();
     test<std::vector<bool, test_allocator<bool> > >();
@@ -102,4 +102,6 @@ int main() {
     test<std::unordered_multimap<int, int, std::hash<int>, std::equal_to<int>,
                                  test_allocator<KV> > >(stored_allocators);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.requirements/container.requirements.general/nothing_to_do.pass.cpp b/libcxx/test/std/containers/container.requirements/container.requirements.general/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/containers/container.requirements/container.requirements.general/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/containers/container.requirements/container.requirements.general/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.requirements/nothing_to_do.pass.cpp b/libcxx/test/std/containers/container.requirements/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/containers/container.requirements/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/containers/container.requirements/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.requirements/sequence.reqmts/nothing_to_do.pass.cpp b/libcxx/test/std/containers/container.requirements/sequence.reqmts/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/containers/container.requirements/sequence.reqmts/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/containers/container.requirements/sequence.reqmts/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.requirements/unord.req/nothing_to_do.pass.cpp b/libcxx/test/std/containers/container.requirements/unord.req/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/containers/container.requirements/unord.req/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/containers/container.requirements/unord.req/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/container.requirements/unord.req/unord.req.except/nothing_to_do.pass.cpp b/libcxx/test/std/containers/container.requirements/unord.req/unord.req.except/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/containers/container.requirements/unord.req/unord.req.except/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/containers/container.requirements/unord.req/unord.req.except/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/containers.general/nothing_to_do.pass.cpp b/libcxx/test/std/containers/containers.general/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/containers/containers.general/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/containers/containers.general/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/nothing_to_do.pass.cpp b/libcxx/test/std/containers/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/containers/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/containers/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/array.cons/deduct.fail.cpp b/libcxx/test/std/containers/sequences/array/array.cons/deduct.fail.cpp
index fb882eea071a57c224583a1b521380feb82dcde5..0c0d32f69c1ef27a6d713cfc8d44410cc9abd98c 100644
--- a/libcxx/test/std/containers/sequences/array/array.cons/deduct.fail.cpp
+++ b/libcxx/test/std/containers/sequences/array/array.cons/deduct.fail.cpp
@@ -28,9 +28,11 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::array arr{1,2,3L}; // expected-error {{no viable constructor or deduction guide for deduction of template arguments of 'array'}}
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/array.cons/deduct.pass.cpp b/libcxx/test/std/containers/sequences/array/array.cons/deduct.pass.cpp
index fead8cacfdeeadedcb48e9fe62716e3bdcc9f7e0..141aafc2a318fbd9727db2384f578e01293a1b1a 100644
--- a/libcxx/test/std/containers/sequences/array/array.cons/deduct.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/array.cons/deduct.pass.cpp
@@ -30,7 +30,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 //  Test the explicit deduction guides
     {
@@ -61,4 +61,6 @@ int main()
     assert(arr[0] == 4.0);
     assert(arr[1] == 5.0);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/array.cons/default.pass.cpp b/libcxx/test/std/containers/sequences/array/array.cons/default.pass.cpp
index 22ed4d8320f4618185c9cc9577a2b2081f827829..daa6a52521082762c8d75cb450f1604320e5fe80 100644
--- a/libcxx/test/std/containers/sequences/array/array.cons/default.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/array.cons/default.pass.cpp
@@ -21,7 +21,7 @@ struct NoDefault {
   NoDefault(int) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -44,4 +44,6 @@ int main()
       C c2 = {{}};
       assert(c2.size() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/array.cons/implicit_copy.pass.cpp b/libcxx/test/std/containers/sequences/array/array.cons/implicit_copy.pass.cpp
index 9d82c93b52c50a47ca89fd58e4af79c0a567ba4b..c0e205c8322a499ecdcbdaf8b152cef4559b13f4 100644
--- a/libcxx/test/std/containers/sequences/array/array.cons/implicit_copy.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/array.cons/implicit_copy.pass.cpp
@@ -32,7 +32,7 @@ struct NoDefault {
   NoDefault(int) {}
 };
 
-int main() {
+int main(int, char**) {
   {
     typedef double T;
     typedef std::array<T, 3> C;
@@ -89,4 +89,6 @@ int main() {
     TEST_NOT_COPY_ASSIGNABLE(C);
   }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/array.cons/initializer_list.pass.cpp b/libcxx/test/std/containers/sequences/array/array.cons/initializer_list.pass.cpp
index 6a9da4e4fdd5b1f32c0e3e33bed82130a2806f93..e85269796fb92132340bb3e75c1b1218b8aae36c 100644
--- a/libcxx/test/std/containers/sequences/array/array.cons/initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/array.cons/initializer_list.pass.cpp
@@ -17,7 +17,7 @@
 // Disable the missing braces warning for this reason.
 #include "disable_missing_braces_warning.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -48,4 +48,6 @@ int main()
         C c = {};
         assert(c.size() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/array.data/data.pass.cpp b/libcxx/test/std/containers/sequences/array/array.data/data.pass.cpp
index 36640160ee2c378d60b63b3abfce79f849805965..ce1843eb5496b0fb75975e384a04b6906595c1a3 100644
--- a/libcxx/test/std/containers/sequences/array/array.data/data.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/array.data/data.pass.cpp
@@ -25,7 +25,7 @@ struct NoDefault {
 };
 
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -67,4 +67,6 @@ int main()
       T* p = c.data();
       LIBCPP_ASSERT(p != nullptr);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/array.data/data_const.pass.cpp b/libcxx/test/std/containers/sequences/array/array.data/data_const.pass.cpp
index 3b035e67ca952df565d70f7d2c863a64bdd2c31d..32c05d7ef35922ea20bd6fa568b23a728bc90c80 100644
--- a/libcxx/test/std/containers/sequences/array/array.data/data_const.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/array.data/data_const.pass.cpp
@@ -24,7 +24,7 @@ struct NoDefault {
   NoDefault(int) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -70,4 +70,6 @@ int main()
         static_assert ( *c2.data()  ==  c2[0], "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/array.fill/fill.fail.cpp b/libcxx/test/std/containers/sequences/array/array.fill/fill.fail.cpp
index 96641c5cb9de56f6699ef5cf21dac2b3d749ed6d..9f560dab4e43f716ae3033cc21c79c887dc3dda6 100644
--- a/libcxx/test/std/containers/sequences/array/array.fill/fill.fail.cpp
+++ b/libcxx/test/std/containers/sequences/array/array.fill/fill.fail.cpp
@@ -17,7 +17,7 @@
 // Disable the missing braces warning for this reason.
 #include "disable_missing_braces_warning.h"
 
-int main() {
+int main(int, char**) {
   {
     typedef double T;
     typedef std::array<const T, 0> C;
@@ -25,4 +25,6 @@ int main() {
     // expected-error-re@array:* {{static_assert failed {{.*}}"cannot fill zero-sized array of type 'const T'"}}
     c.fill(5.5); // expected-note {{requested here}}
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/array.fill/fill.pass.cpp b/libcxx/test/std/containers/sequences/array/array.fill/fill.pass.cpp
index d4dfe9a711932a8bf43bae0702ce825c24b8a449..db7363ab9757a6d3aeddfdfb5643a97bb619f33f 100644
--- a/libcxx/test/std/containers/sequences/array/array.fill/fill.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/array.fill/fill.pass.cpp
@@ -17,7 +17,7 @@
 // Disable the missing braces warning for this reason.
 #include "disable_missing_braces_warning.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -36,4 +36,6 @@ int main()
         c.fill(5.5);
         assert(c.size() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/array.size/size.pass.cpp b/libcxx/test/std/containers/sequences/array/array.size/size.pass.cpp
index 038df0160dc2483b800f7d57f3ea7b1ec084737d..f837bdcf8fb82148e05dad863ed0dc4a5f696239 100644
--- a/libcxx/test/std/containers/sequences/array/array.size/size.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/array.size/size.pass.cpp
@@ -19,7 +19,7 @@
 // Disable the missing braces warning for this reason.
 #include "disable_missing_braces_warning.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -55,4 +55,6 @@ int main()
         static_assert(c.empty(), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/array.special/swap.pass.cpp b/libcxx/test/std/containers/sequences/array/array.special/swap.pass.cpp
index f4751cc7661df46a79dc44bf4f1769f049702cdb..6c9ed957b836bf7d56102aa816119a547fccab6d 100644
--- a/libcxx/test/std/containers/sequences/array/array.special/swap.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/array.special/swap.pass.cpp
@@ -35,7 +35,7 @@ std::false_type can_swap_imp(...);
 template <class Tp>
 struct can_swap : std::is_same<decltype(can_swap_imp<Tp>(0)), void> {};
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -81,4 +81,6 @@ int main()
         static_assert(!can_swap<C1&>::value, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/array.swap/swap.fail.cpp b/libcxx/test/std/containers/sequences/array/array.swap/swap.fail.cpp
index 3e5dc815c248e6ea7b66051db00d589c839319e7..90c1496156aace3d5a2a0742cb85313f72e31e04 100644
--- a/libcxx/test/std/containers/sequences/array/array.swap/swap.fail.cpp
+++ b/libcxx/test/std/containers/sequences/array/array.swap/swap.fail.cpp
@@ -17,7 +17,7 @@
 // Disable the missing braces warning for this reason.
 #include "disable_missing_braces_warning.h"
 
-int main() {
+int main(int, char**) {
   {
     typedef double T;
     typedef std::array<const T, 0> C;
@@ -26,4 +26,6 @@ int main() {
     // expected-error-re@array:* {{static_assert failed {{.*}}"cannot swap zero-sized array of type 'const T'"}}
     c.swap(c2); // expected-note {{requested here}}
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/array.swap/swap.pass.cpp b/libcxx/test/std/containers/sequences/array/array.swap/swap.pass.cpp
index e23daa88e7976887e4f79f13342adafd4d5d3895..aac8a13b29a38234f8ff282880b77f587e34ca43 100644
--- a/libcxx/test/std/containers/sequences/array/array.swap/swap.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/array.swap/swap.pass.cpp
@@ -27,7 +27,7 @@ private:
   NonSwappable& operator=(NonSwappable const&);
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -89,4 +89,6 @@ int main()
 #endif
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/array.tuple/get.fail.cpp b/libcxx/test/std/containers/sequences/array/array.tuple/get.fail.cpp
index 25bf53835a08c78b6a87c79a67708c0abe4640e9..7bfe670b20d4b58d70734133dbc25d22f1777e7b 100644
--- a/libcxx/test/std/containers/sequences/array/array.tuple/get.fail.cpp
+++ b/libcxx/test/std/containers/sequences/array/array.tuple/get.fail.cpp
@@ -23,7 +23,7 @@
 // Disable the missing braces warning for this reason.
 #include "disable_missing_braces_warning.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -32,4 +32,6 @@ int main()
         std::get<3>(c) = 5.5; // expected-note {{requested here}}
         // expected-error-re@array:* {{static_assert failed{{( due to requirement '3U[L]{0,2} < 3U[L]{0,2}')?}} "Index out of bounds in std::get<> (std::array)"}}
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/array.tuple/get.pass.cpp b/libcxx/test/std/containers/sequences/array/array.tuple/get.pass.cpp
index bbc1c071a79b6b401a9c73acefea9175482b039d..9e94417ac9733c96252374c15778cef0769d7e4f 100644
--- a/libcxx/test/std/containers/sequences/array/array.tuple/get.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/array.tuple/get.pass.cpp
@@ -30,7 +30,7 @@ struct S {
 constexpr std::array<int, 2> getArr () { return { 3, 4 }; }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -55,4 +55,6 @@ int main()
         static_assert(std::get<1>(getArr()) == 4, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/array.tuple/get_const.pass.cpp b/libcxx/test/std/containers/sequences/array/array.tuple/get_const.pass.cpp
index 7b964870b37b84dfda37cc91adacbb01abb57c75..b22a76185b6fcd678abf4fd68c58ad40abd91207 100644
--- a/libcxx/test/std/containers/sequences/array/array.tuple/get_const.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/array.tuple/get_const.pass.cpp
@@ -19,7 +19,7 @@
 // Disable the missing braces warning for this reason.
 #include "disable_missing_braces_warning.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -39,4 +39,6 @@ int main()
         static_assert(std::get<2>(c) == 3.5, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/array.tuple/get_const_rv.pass.cpp b/libcxx/test/std/containers/sequences/array/array.tuple/get_const_rv.pass.cpp
index 599e919a384864f4c0c3ee079bdfd74d4134efec..ce8fc4fd3651c1fd0a1f0ec2d105a5e5d7ed9533 100644
--- a/libcxx/test/std/containers/sequences/array/array.tuple/get_const_rv.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/array.tuple/get_const_rv.pass.cpp
@@ -24,7 +24,7 @@
 // Disable the missing braces warning for this reason.
 #include "disable_missing_braces_warning.h"
 
-int main()
+int main(int, char**)
 {
 
     {
@@ -47,4 +47,6 @@ int main()
     static_assert(std::get<2>(std::move(c)) == 3.5, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/array.tuple/get_rv.pass.cpp b/libcxx/test/std/containers/sequences/array/array.tuple/get_rv.pass.cpp
index 77d4633db5ec4dd7beaa31cf3b342c59cefaddd0..d36fcdcc206680748759925db734aedcf7c53982 100644
--- a/libcxx/test/std/containers/sequences/array/array.tuple/get_rv.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/array.tuple/get_rv.pass.cpp
@@ -21,7 +21,7 @@
 // Disable the missing braces warning for this reason.
 #include "disable_missing_braces_warning.h"
 
-int main()
+int main(int, char**)
 {
 
     {
@@ -31,4 +31,6 @@ int main()
         T t = std::get<0>(std::move(c));
         assert(*t == 3.5);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/array.tuple/tuple_element.fail.cpp b/libcxx/test/std/containers/sequences/array/array.tuple/tuple_element.fail.cpp
index 35cd986471723302163e6a18b0518f76a541e7c7..a4fbd3ab4c2147f70a24445e6feab52f009ddd50 100644
--- a/libcxx/test/std/containers/sequences/array/array.tuple/tuple_element.fail.cpp
+++ b/libcxx/test/std/containers/sequences/array/array.tuple/tuple_element.fail.cpp
@@ -23,7 +23,7 @@
 // Disable the missing braces warning for this reason.
 #include "disable_missing_braces_warning.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -31,4 +31,6 @@ int main()
         std::tuple_element<3, C> foo; // expected-note {{requested here}}
         // expected-error-re@array:* {{static_assert failed{{( due to requirement '3U[L]{0,2} < 3U[L]{0,2}')?}} "Index out of bounds in std::tuple_element<> (std::array)"}}
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/array.tuple/tuple_element.pass.cpp b/libcxx/test/std/containers/sequences/array/array.tuple/tuple_element.pass.cpp
index 6980838ab63db48ae053d1100f0e44ca684d123c..fbf5210f26fcfbc2b7fd3bca68c17ed92e940703 100644
--- a/libcxx/test/std/containers/sequences/array/array.tuple/tuple_element.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/array.tuple/tuple_element.pass.cpp
@@ -46,8 +46,10 @@ void test()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<double>();
     test<int>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/array.tuple/tuple_size.pass.cpp b/libcxx/test/std/containers/sequences/array/array.tuple/tuple_size.pass.cpp
index e542f34eefbb754799673fa243c88c2cf4b78295..dddcbcaff7f37dc86d1f38b812aa10873308db09 100644
--- a/libcxx/test/std/containers/sequences/array/array.tuple/tuple_size.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/array.tuple/tuple_size.pass.cpp
@@ -33,9 +33,11 @@ void test()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<double, 0>();
     test<double, 3>();
     test<double, 5>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/array.zero/tested_elsewhere.pass.cpp b/libcxx/test/std/containers/sequences/array/array.zero/tested_elsewhere.pass.cpp
index ba3c5405d075762f8bfb7c2a9f1c7af484976c2a..966e603d13481dcd5a0e3e8feaa92f8a0addd973 100644
--- a/libcxx/test/std/containers/sequences/array/array.zero/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/array.zero/tested_elsewhere.pass.cpp
@@ -12,6 +12,8 @@
 
 #include <array>
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/at.pass.cpp b/libcxx/test/std/containers/sequences/array/at.pass.cpp
index b8d1d2b804bbe07e45431bd43db6e281a955e9d9..0240d5a83728d65cfb98dfacfd2b18c0702b6978 100644
--- a/libcxx/test/std/containers/sequences/array/at.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/at.pass.cpp
@@ -30,7 +30,7 @@ constexpr bool check_idx( size_t idx, double val )
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -116,4 +116,6 @@ int main()
         static_assert (check_idx(2, 3.5), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/begin.pass.cpp b/libcxx/test/std/containers/sequences/array/begin.pass.cpp
index ce023aa3890e621ec632eaa5d6e3b816a7fd61f4..7b26d231dbdd91e3e9f264e58d98ff4cf4e14fba 100644
--- a/libcxx/test/std/containers/sequences/array/begin.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/begin.pass.cpp
@@ -24,7 +24,7 @@ struct NoDefault {
 };
 
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -48,4 +48,6 @@ int main()
       LIBCPP_ASSERT(ib != nullptr);
       LIBCPP_ASSERT(ie != nullptr);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/compare.fail.cpp b/libcxx/test/std/containers/sequences/array/compare.fail.cpp
index 1710fe7888bb8943096beb4d1ef3f86d976158cc..47859ad49db525070819fd1c3b4d5e3edac8c385 100644
--- a/libcxx/test/std/containers/sequences/array/compare.fail.cpp
+++ b/libcxx/test/std/containers/sequences/array/compare.fail.cpp
@@ -41,7 +41,7 @@ void test_compare(const Array& LHS, const Array& RHS) {
 
 template <int Dummy> struct NoCompare {};
 
-int main()
+int main(int, char**)
 {
   {
     typedef NoCompare<0> T;
@@ -67,4 +67,6 @@ int main()
     TEST_IGNORE_NODISCARD (c1 == c1);
     TEST_IGNORE_NODISCARD (c1 < c1);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/compare.pass.cpp b/libcxx/test/std/containers/sequences/array/compare.pass.cpp
index 56eabbd00ab497d58c95ad1ec7ca711964d7a100..c05dd19405bff2acaee17d2e9b8625314ab79c3c 100644
--- a/libcxx/test/std/containers/sequences/array/compare.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/compare.pass.cpp
@@ -28,7 +28,7 @@
 // Disable the missing braces warning for this reason.
 #include "disable_missing_braces_warning.h"
 
-int main()
+int main(int, char**)
 {
   {
     typedef int T;
@@ -58,4 +58,6 @@ int main()
   static_assert(testComparisons6(a2, a1, false, false), "");
   }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/contiguous.pass.cpp b/libcxx/test/std/containers/sequences/array/contiguous.pass.cpp
index ce953794a5616e71b2194a54adf8bc3c532001e2..e0ab5b61c44340d3559b0dffb6e7b54f298a498a 100644
--- a/libcxx/test/std/containers/sequences/array/contiguous.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/contiguous.pass.cpp
@@ -20,11 +20,13 @@ void test_contiguous ( const C &c )
         assert ( *(c.begin() + i) == *(std::addressof(*c.begin()) + i));
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
         typedef std::array<T, 3> C;
         test_contiguous (C());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/empty.fail.cpp b/libcxx/test/std/containers/sequences/array/empty.fail.cpp
index 424f715413d0385924fe79004a1cdafc5187c83d..3bbb3c8e1c04532001fe95f36a3677683a0d0271 100644
--- a/libcxx/test/std/containers/sequences/array/empty.fail.cpp
+++ b/libcxx/test/std/containers/sequences/array/empty.fail.cpp
@@ -20,11 +20,13 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
 
     std::array<int, 1> c;
     c.empty(); // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
     std::array<int, 0> c0;
     c0.empty(); // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/empty.pass.cpp b/libcxx/test/std/containers/sequences/array/empty.pass.cpp
index 48580694708624a6926a1aed2821519882ff5a97..a17aa50c5b2198b0c57cc59c4bf345dff3172dfc 100644
--- a/libcxx/test/std/containers/sequences/array/empty.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/empty.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::array<int, 2> C;
@@ -32,4 +32,6 @@ int main()
     ASSERT_NOEXCEPT(c.empty());
     assert( c.empty());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/front_back.pass.cpp b/libcxx/test/std/containers/sequences/array/front_back.pass.cpp
index 13368683a56fdfdd3f4e65f2f15d0f986d506fdd..1a714369ffc3fb558bbc78cf0752f540b961d861 100644
--- a/libcxx/test/std/containers/sequences/array/front_back.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/front_back.pass.cpp
@@ -36,7 +36,7 @@ constexpr bool check_back( double val )
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -115,4 +115,6 @@ int main()
         static_assert (check_back (3.5), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/indexing.pass.cpp b/libcxx/test/std/containers/sequences/array/indexing.pass.cpp
index a33a597fc5e1c8007fcff8f478376edf8d061d84..bf55711a14180f8dfa1906c1307a99c9d8ee984e 100644
--- a/libcxx/test/std/containers/sequences/array/indexing.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/indexing.pass.cpp
@@ -30,7 +30,7 @@ constexpr bool check_idx( size_t idx, double val )
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -104,4 +104,6 @@ int main()
         static_assert (check_idx(2, 3.5), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/iterators.pass.cpp b/libcxx/test/std/containers/sequences/array/iterators.pass.cpp
index 7e4c9b756206d76bfae1543fb452c35b90cdf84c..71fad183ff730a43fc4262b5a57d5b57decb3b76 100644
--- a/libcxx/test/std/containers/sequences/array/iterators.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/iterators.pass.cpp
@@ -20,7 +20,7 @@
 // Disable the missing braces warning for this reason.
 #include "disable_missing_braces_warning.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::array<int, 5> C;
@@ -141,4 +141,6 @@ int main()
         static_assert ( *std::crbegin(c) == 4, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/max_size.pass.cpp b/libcxx/test/std/containers/sequences/array/max_size.pass.cpp
index 1f3ec0472ae2f12e4472a615f9e44afff9938bd7..a0b77392ee80420b59dc494ca4cc0e89df0ebe89 100644
--- a/libcxx/test/std/containers/sequences/array/max_size.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/max_size.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::array<int, 2> C;
@@ -32,4 +32,6 @@ int main()
     ASSERT_NOEXCEPT(c.max_size());
     assert(c.max_size() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/size_and_alignment.pass.cpp b/libcxx/test/std/containers/sequences/array/size_and_alignment.pass.cpp
index c57740bcaa5b603e0d1315a5a031f22421a556fa..f585da6ce7a1267d8d4035f862613a546c128c46 100644
--- a/libcxx/test/std/containers/sequences/array/size_and_alignment.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/size_and_alignment.pass.cpp
@@ -57,7 +57,9 @@ struct TEST_ALIGNAS(TEST_ALIGNOF(std::max_align_t) * 2) TestType2 {
   char data[1000];
 };
 
-int main() {
+//static_assert(sizeof(void*) == 4, "");
+
+int main(int, char**) {
   test_type<char>();
   test_type<int>();
   test_type<double>();
@@ -65,4 +67,6 @@ int main() {
   test_type<std::max_align_t>();
   test_type<TestType1>();
   test_type<TestType2>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/array/types.pass.cpp b/libcxx/test/std/containers/sequences/array/types.pass.cpp
index e76c06e6d460668e4743cc44d3e804b429bb8c70..f86e008d2e8defab4008a1a290d498fd4ed2a648 100644
--- a/libcxx/test/std/containers/sequences/array/types.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/types.pass.cpp
@@ -47,7 +47,7 @@ void test_iterators() {
     static_assert((std::is_same<typename CItT::difference_type, typename C::difference_type>::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -93,4 +93,6 @@ int main()
         static_assert((std::is_same<typename C::difference_type,
             typename std::iterator_traits<typename C::const_iterator>::difference_type>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/allocator_mismatch.fail.cpp b/libcxx/test/std/containers/sequences/deque/allocator_mismatch.fail.cpp
index 769aa9ec113381c90c23b6838adba22a76c46246..287faf75ec44813f9f07d9656000b092b59ff34e 100644
--- a/libcxx/test/std/containers/sequences/deque/allocator_mismatch.fail.cpp
+++ b/libcxx/test/std/containers/sequences/deque/allocator_mismatch.fail.cpp
@@ -11,7 +11,9 @@
 
 #include <deque>
 
-int main()
+int main(int, char**)
 {
     std::deque<int, std::allocator<long> > d;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.capacity/access.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.capacity/access.pass.cpp
index b63784312d229dcb19e2ac16fab4bdcb64c0e869..86c518450f9e4a02f8d4a28c2ecbc26873c2b443 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.capacity/access.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.capacity/access.pass.cpp
@@ -47,7 +47,7 @@ make(int size, int start = 0 )
     return c;
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::deque<int> c = make<std::deque<int> >(10);
@@ -87,4 +87,6 @@ int main()
         assert(c.back() == 9);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.capacity/empty.fail.cpp b/libcxx/test/std/containers/sequences/deque/deque.capacity/empty.fail.cpp
index 701e318973c2a70b5438b366b6d41cf681295e7f..79e4b30b2b27da79c78e0ee276d4bdc18d8cbce4 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.capacity/empty.fail.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.capacity/empty.fail.cpp
@@ -20,8 +20,10 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     std::deque<int> c;
     c.empty();  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.capacity/empty.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.capacity/empty.pass.cpp
index 7adf6656a7eaf3690a54c9a7ddec8eda3def0cc6..38859411067d44a5434dcab91d90dde2358dad9e 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.capacity/empty.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.capacity/empty.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::deque<int> C;
@@ -42,4 +42,6 @@ int main()
     assert(c.empty());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.capacity/max_size.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.capacity/max_size.pass.cpp
index d5b3cc521e6b341be22e5410084c1c0ec8538d0a..230a46519b107642edab2f898aadc0df40080d98 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.capacity/max_size.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.capacity/max_size.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_allocator.h"
 #include "test_macros.h"
 
-int main() {
+int main(int, char**) {
   {
     typedef limited_allocator<int, 10> A;
     typedef std::deque<int, A> C;
@@ -43,4 +43,6 @@ int main() {
     assert(c.max_size() <= max_dist);
     assert(c.max_size() <= alloc_max_size(c.get_allocator()));
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.capacity/resize_size.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.capacity/resize_size.pass.cpp
index 6ef329ee62fda3022259827e79b882ce5d509a37..9161592213b9b8514cf7b4c31ec51d0af9054a91 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.capacity/resize_size.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.capacity/resize_size.pass.cpp
@@ -65,7 +65,7 @@ testN(int start, int N, int M)
     test(c1, M);
 }
 
-int main()
+int main(int, char**)
 {
     {
     int rng[] = {0, 1, 2, 3, 1023, 1024, 1025, 2047, 2048, 2049};
@@ -85,4 +85,6 @@ int main()
                 testN<std::deque<int, min_allocator<int>>>(rng[i], rng[j], rng[k]);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.capacity/resize_size_value.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.capacity/resize_size_value.pass.cpp
index 02910d8bf50d2cd4393524c07b3614bbf1115d6b..876ff2fe5adbe4dd208cdcc4f73c031b536a0a7e 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.capacity/resize_size_value.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.capacity/resize_size_value.pass.cpp
@@ -65,7 +65,7 @@ testN(int start, int N, int M)
     test(c1, M, -10);
 }
 
-int main()
+int main(int, char**)
 {
     {
     int rng[] = {0, 1, 2, 3, 1023, 1024, 1025, 2047, 2048, 2049};
@@ -85,4 +85,6 @@ int main()
                 testN<std::deque<int, min_allocator<int>>>(rng[i], rng[j], rng[k]);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.capacity/shrink_to_fit.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.capacity/shrink_to_fit.pass.cpp
index e4f0e2bd002caae6235da9bc42f17acead69e123..bde2eaaaa38ee342ea16717851c1fb386ca68860 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.capacity/shrink_to_fit.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.capacity/shrink_to_fit.pass.cpp
@@ -55,7 +55,7 @@ testN(int start, int N)
     test(c1);
 }
 
-int main()
+int main(int, char**)
 {
     {
     int rng[] = {0, 1, 2, 3, 1023, 1024, 1025, 2047, 2048, 2049};
@@ -73,4 +73,6 @@ int main()
             testN<std::deque<int, min_allocator<int>> >(rng[i], rng[j]);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.capacity/size.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.capacity/size.pass.cpp
index 2b89c0490d996cb333fa696d76f9a9c2593d29ea..c70abe421cf287c300270c9e95f5473b17796c82 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.capacity/size.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.capacity/size.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::deque<int> C;
@@ -58,4 +58,6 @@ int main()
     assert(c.size() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.cons/alloc.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.cons/alloc.pass.cpp
index 4dcea9782af5f5b38cced36c3316504ae78818f8..e2700b958a73d161ec0db852b51b082c006770d8 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.cons/alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.cons/alloc.pass.cpp
@@ -26,7 +26,7 @@ test(const Allocator& a)
     assert(d.get_allocator() == a);
 }
 
-int main()
+int main(int, char**)
 {
     test<int>(std::allocator<int>());
     test<NotConstructible>(test_allocator<NotConstructible>(3));
@@ -36,4 +36,6 @@ int main()
     test<int>(explicit_allocator<int>());
     test<NotConstructible>(explicit_allocator<NotConstructible>{});
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.cons/assign_initializer_list.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.cons/assign_initializer_list.pass.cpp
index 5441583fa81f4af533f5bb9a322e83e0060463e4..edca369a54ab5b1cb35244d3e3a60b1233f45c9f 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.cons/assign_initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.cons/assign_initializer_list.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::deque<int> d;
@@ -37,4 +37,6 @@ int main()
     assert(d[2] == 5);
     assert(d[3] == 6);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.cons/assign_iter_iter.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.cons/assign_iter_iter.pass.cpp
index 6b3b3f19a435586eb3b5fa4461c1dad5029bec3d..d59943574f001ba3b709bfe85f6ff8ec08757d2c 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.cons/assign_iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.cons/assign_iter_iter.pass.cpp
@@ -149,7 +149,9 @@ void test_emplacable_concept() {
 #endif
 }
 
-int main() {
+int main(int, char**) {
   basic_test();
   test_emplacable_concept();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.cons/assign_size_value.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.cons/assign_size_value.pass.cpp
index ba18ab24eb32f7d73d824487dc6f7907edc3b0fb..2875a1776268e55acaf97932b5dcd46b50b6cbd0 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.cons/assign_size_value.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.cons/assign_size_value.pass.cpp
@@ -60,7 +60,7 @@ testN(int start, int N, int M)
     test(c1, M, -10);
 }
 
-int main()
+int main(int, char**)
 {
     {
     int rng[] = {0, 1, 2, 3, 1023, 1024, 1025, 2047, 2048, 2049};
@@ -80,4 +80,6 @@ int main()
                 testN<std::deque<int, min_allocator<int>> >(rng[i], rng[j], rng[k]);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.cons/copy.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.cons/copy.pass.cpp
index bb5bb1393c089e567e09502f010e0fa2b9da0914..2d42ee38a50899c2ba5236eaa84e5b65c9d016a0 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.cons/copy.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.cons/copy.pass.cpp
@@ -25,7 +25,7 @@ test(const C& x)
     assert(c == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
         int ab[] = {3, 4, 2, 8, 0, 1, 44, 34, 45, 96, 80, 1, 13, 31, 45};
@@ -57,4 +57,6 @@ int main()
         assert(v2.get_allocator() == v.get_allocator());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.cons/copy_alloc.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.cons/copy_alloc.pass.cpp
index 138e6bdc7e0357f3a9a4fa5586c1e10212af24b8..4334fd6a539c8ff700db26f7218dc06ba667f942 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.cons/copy_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.cons/copy_alloc.pass.cpp
@@ -25,7 +25,7 @@ test(const C& x, const typename C::allocator_type& a)
     assert(c.get_allocator() == a);
 }
 
-int main()
+int main(int, char**)
 {
     {
         int ab[] = {3, 4, 2, 8, 0, 1, 44, 34, 45, 96, 80, 1, 13, 31, 45};
@@ -47,4 +47,6 @@ int main()
                                                           min_allocator<int>());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.cons/deduct.fail.cpp b/libcxx/test/std/containers/sequences/deque/deque.cons/deduct.fail.cpp
index 3180384aab51b8d9340b34bfaa6c1740068bf75f..99bf89c7908dceb5e83abc6248b9c17f40e76eb7 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.cons/deduct.fail.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.cons/deduct.fail.cpp
@@ -25,7 +25,7 @@
 
 struct A {};
 
-int main()
+int main(int, char**)
 {
 //  Test the explicit deduction guides
 
@@ -38,4 +38,6 @@ int main()
 //      deque<allocator<int>, allocator<allocator<int>>>
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.cons/deduct.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.cons/deduct.pass.cpp
index b349819cc7b925d869a3234820d8a0a3bfce83a4..ac08613818a95e281d40ba9caca623c68e275d82 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.cons/deduct.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.cons/deduct.pass.cpp
@@ -29,7 +29,7 @@
 
 struct A {};
 
-int main()
+int main(int, char**)
 {
 
 //  Test the explicit deduction guides
@@ -94,4 +94,6 @@ int main()
     static_assert(std::is_same_v<decltype(deq)::allocator_type, std::allocator<long double>>, "");
     assert(deq.size() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.cons/default.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.cons/default.pass.cpp
index bb84f05f49db3410baa6b267d16469fdc3551fd1..f132eb5bee85d65a91201db0655342a6aca08112 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.cons/default.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.cons/default.pass.cpp
@@ -29,7 +29,7 @@ test()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test<int, std::allocator<int> >();
     test<NotConstructible, limited_allocator<NotConstructible, 1> >();
@@ -37,4 +37,6 @@ int main()
     test<int, min_allocator<int> >();
     test<NotConstructible, min_allocator<NotConstructible> >();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.cons/default_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.cons/default_noexcept.pass.cpp
index fea4799d54da22ef2d10328c792aa6adcfe301a7..abc3de7db991bc043e1347a1237bba6112d6da71 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.cons/default_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.cons/default_noexcept.pass.cpp
@@ -29,7 +29,7 @@ struct some_alloc
     some_alloc(const some_alloc&);
 };
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -49,4 +49,6 @@ int main()
         typedef std::deque<MoveOnly, some_alloc<MoveOnly>> C;
         static_assert(!std::is_nothrow_default_constructible<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.cons/dtor_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.cons/dtor_noexcept.pass.cpp
index 3dcc15045e20ccd5045c9e8368cfb452e91cd4cc..7e09148b4fd7c2a29d85f8140061fd817d7125b2 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.cons/dtor_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.cons/dtor_noexcept.pass.cpp
@@ -27,7 +27,7 @@ struct some_alloc
     ~some_alloc() noexcept(false);
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::deque<MoveOnly> C;
@@ -47,4 +47,6 @@ int main()
         static_assert(!std::is_nothrow_destructible<C>::value, "");
     }
 #endif // _LIBCPP_VERSION
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.cons/initializer_list.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.cons/initializer_list.pass.cpp
index b76d0cca57877481bd56663bef3e928ed0ae1ab5..02cbadd6c68ee7c45dabbc0ae5cabd2c8d3bab03 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.cons/initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.cons/initializer_list.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::deque<int> d = {3, 4, 5, 6};
@@ -35,4 +35,6 @@ int main()
     assert(d[2] == 5);
     assert(d[3] == 6);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.cons/initializer_list_alloc.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.cons/initializer_list_alloc.pass.cpp
index e412e94e7e94c9f75598a9b3c99aeead3b379920..1450c978b68824c559ead03730e721c71c199ffd 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.cons/initializer_list_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.cons/initializer_list_alloc.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::deque<int, test_allocator<int>> d({3, 4, 5, 6}, test_allocator<int>(3));
@@ -38,4 +38,6 @@ int main()
     assert(d[2] == 5);
     assert(d[3] == 6);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.cons/iter_iter.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.cons/iter_iter.pass.cpp
index 6c68cd09016a6328dca7ceacd11777d66f44a89f..214ac8303bd73f52e6cc5e5379896e73b49250f7 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.cons/iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.cons/iter_iter.pass.cpp
@@ -105,7 +105,9 @@ void test_emplacable_concept() {
 #endif
 }
 
-int main() {
+int main(int, char**) {
   basic_test();
   test_emplacable_concept();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.cons/iter_iter_alloc.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.cons/iter_iter_alloc.pass.cpp
index c6391620b2e5a013a3774de17f1b6a7347102943..c72f73a9a8a2bbab213d9333d776ed48fa306731 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.cons/iter_iter_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.cons/iter_iter_alloc.pass.cpp
@@ -96,7 +96,9 @@ void test_emplacable_concept() {
 #endif
 }
 
-int main() {
+int main(int, char**) {
   basic_test();
   test_emplacable_concept();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.cons/move.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.cons/move.pass.cpp
index ee628c6aa99c59dac6effe26abeec78836e7ce36..b8fdc989247ef8b3e81c73779bff95187f8ad6fe 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.cons/move.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.cons/move.pass.cpp
@@ -19,7 +19,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         int ab[] = {3, 4, 2, 8, 0, 1, 44, 34, 45, 96, 80, 1, 13, 31, 45};
@@ -68,4 +68,6 @@ int main()
         assert(c1.size() == 0);
         assert(c3.get_allocator() == c1.get_allocator());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.cons/move_alloc.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.cons/move_alloc.pass.cpp
index 54ce39d7e80efa9b51eaf446906eb21eeae174a5..68dd99f105bb1582ad828e541015fedde3ff91bf 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.cons/move_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.cons/move_alloc.pass.cpp
@@ -20,7 +20,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         int ab[] = {3, 4, 2, 8, 0, 1, 44, 34, 45, 96, 80, 1, 13, 31, 45};
@@ -82,4 +82,6 @@ int main()
         assert(c3.get_allocator() == A());
         LIBCPP_ASSERT(c1.size() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.cons/move_assign.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.cons/move_assign.pass.cpp
index 325f24c8018dd802bcb0038e83a4dfdb8a1bd677..5fcfbb8d9baa227ad21a5926a6f009bf2ba73693 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.cons/move_assign.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.cons/move_assign.pass.cpp
@@ -19,7 +19,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         int ab[] = {3, 4, 2, 8, 0, 1, 44, 34, 45, 96, 80, 1, 13, 31, 45};
@@ -85,4 +85,6 @@ int main()
         assert(c1.size() == 0);
         assert(c3.get_allocator() == A());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.cons/move_assign_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.cons/move_assign_noexcept.pass.cpp
index 3facd3084dc8489eea3810d2fe0e45a74ce09b42..1d86c14aadd47cf724eccff71d1198f68a405a78 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.cons/move_assign_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.cons/move_assign_noexcept.pass.cpp
@@ -31,7 +31,7 @@ struct some_alloc
     some_alloc(const some_alloc&);
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::deque<MoveOnly> C;
@@ -51,4 +51,6 @@ int main()
         static_assert(!std::is_nothrow_move_assignable<C>::value, "");
     }
 #endif // _LIBCPP_VERSION
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.cons/move_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.cons/move_noexcept.pass.cpp
index b5d3331f43ca0f2651ec169d12010e7597bed213..8b4b4fb1fa5b87626678dd232104bea47819e0d6 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.cons/move_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.cons/move_noexcept.pass.cpp
@@ -29,7 +29,7 @@ struct some_alloc
     some_alloc(const some_alloc&);
 };
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -49,4 +49,6 @@ int main()
         static_assert(!std::is_nothrow_move_constructible<C>::value, "");
     }
 #endif // _LIBCPP_VERSION
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.cons/op_equal.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.cons/op_equal.pass.cpp
index 22f015950ebc6f935429fdd8d9b97613421c4289..c26ddec0c194913a421450bee4f0f568b356ddfc 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.cons/op_equal.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.cons/op_equal.pass.cpp
@@ -24,7 +24,7 @@ test(const C& x)
     assert(c == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
         int ab[] = {3, 4, 2, 8, 0, 1, 44, 34, 45, 96, 80, 1, 13, 31, 45};
@@ -59,4 +59,6 @@ int main()
         assert(l2.get_allocator() == min_allocator<int>());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.cons/op_equal_initializer_list.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.cons/op_equal_initializer_list.pass.cpp
index 140bb9c7647595921c74321755fc44b3914ef9ad..5f415020128c91d3136aadabb09a40d239a13526 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.cons/op_equal_initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.cons/op_equal_initializer_list.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::deque<int> d;
@@ -37,4 +37,6 @@ int main()
     assert(d[2] == 5);
     assert(d[3] == 6);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.cons/size.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.cons/size.pass.cpp
index fe378e58f84a3207d38b6b5e6d597df34ac5dbdd..b69d2bb598ed56c107964065355e0925d9b2b0ce 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.cons/size.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.cons/size.pass.cpp
@@ -86,7 +86,7 @@ test(unsigned n)
     test2<T, Allocator> ( n );
 }
 
-int main()
+int main(int, char**)
 {
     test<DefaultOnly, std::allocator<DefaultOnly> >(0);
     test<DefaultOnly, std::allocator<DefaultOnly> >(1);
@@ -113,4 +113,6 @@ int main()
     test3<int, min_allocator<int>> (3);
 #endif
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.cons/size_value.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.cons/size_value.pass.cpp
index 8926a879396e5e559f62a65f806f22bac7da62ea..8c432182a679ecdf22985fd146bc94457e264eff 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.cons/size_value.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.cons/size_value.pass.cpp
@@ -30,7 +30,7 @@ test(unsigned n, const T& x)
         assert(*i == x);
 }
 
-int main()
+int main(int, char**)
 {
     test<int, std::allocator<int> >(0, 5);
     test<int, std::allocator<int> >(1, 10);
@@ -48,4 +48,6 @@ int main()
 #if TEST_STD_VER >= 11
     test<int, min_allocator<int> >(4095, 90);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.cons/size_value_alloc.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.cons/size_value_alloc.pass.cpp
index 80218de73659ef0dca16a217321cec00e7f6ddbb..d7e4b3df99165bb4e9002a73f4de201117dc3154 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.cons/size_value_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.cons/size_value_alloc.pass.cpp
@@ -30,7 +30,7 @@ test(unsigned n, const T& x, const Allocator& a)
         assert(*i == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     std::allocator<int> a;
@@ -64,4 +64,6 @@ int main()
     test(4097, 157, a);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.erasure/erase.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.erasure/erase.pass.cpp
index 5af8faef47b862c4b612c678f5c787f566d1a125..2293ef205314566ed2d9489a03f8ac9e71ad3a2d 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.erasure/erase.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.erasure/erase.pass.cpp
@@ -66,7 +66,7 @@ void test()
     test0(S({1,2,1}), opt(3), S({1,2,1}));
 }
 
-int main()
+int main(int, char**)
 {
     test<std::deque<int>>();
     test<std::deque<int, min_allocator<int>>> ();
@@ -74,4 +74,6 @@ int main()
 
     test<std::deque<long>>();
     test<std::deque<double>>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.erasure/erase_if.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.erasure/erase_if.pass.cpp
index 181c73686e2bf47ae557d6e615892f56ff331da4..e0828a3fad8668a349960d7613f88e4f23bf29b1 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.erasure/erase_if.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.erasure/erase_if.pass.cpp
@@ -66,7 +66,7 @@ void test()
     test0(S({1,2,3}), False, S({1,2,3}));
 }
 
-int main()
+int main(int, char**)
 {
     test<std::deque<int>>();
     test<std::deque<int, min_allocator<int>>> ();
@@ -74,4 +74,6 @@ int main()
 
     test<std::deque<long>>();
     test<std::deque<double>>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.modifiers/clear.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.modifiers/clear.pass.cpp
index 8cfa82406db1e49bc6865c832ad518f962c09255..becc36878bf426f63202aabd6fdc9a9575f9b6f0 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.modifiers/clear.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.modifiers/clear.pass.cpp
@@ -17,7 +17,7 @@
 #include "../../../NotConstructible.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef NotConstructible T;
@@ -63,4 +63,6 @@ int main()
         assert(distance(c.begin(), c.end()) == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.modifiers/emplace.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.modifiers/emplace.pass.cpp
index 78278df325c0a6df69f157905917a7d0a72db785..f4713dfdfef7daae10f2518c2354ddc41303383b 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.modifiers/emplace.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.modifiers/emplace.pass.cpp
@@ -86,7 +86,7 @@ testN(int start, int N)
 }
 
 
-int main()
+int main(int, char**)
 {
     {
     int rng[] = {0, 1, 2, 3, 1023, 1024, 1025, 2047, 2048, 2049};
@@ -102,4 +102,6 @@ int main()
         for (int j = 0; j < N; ++j)
             testN<std::deque<Emplaceable, min_allocator<Emplaceable>> >(rng[i], rng[j]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.modifiers/emplace_back.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.modifiers/emplace_back.pass.cpp
index 835a47a5e83edb03ff2c95842fe9e30c11f53af1..ae04c7d17cf6b4581c734b2bdbb92a3e8149c41f 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.modifiers/emplace_back.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.modifiers/emplace_back.pass.cpp
@@ -74,7 +74,7 @@ testN(int start, int N)
     test(c1);
 }
 
-int main()
+int main(int, char**)
 {
     {
     int rng[] = {0, 1, 2, 3, 1023, 1024, 1025, 2047, 2048, 2049};
@@ -101,4 +101,6 @@ int main()
         c.emplace_front(1, 2, 3);
         assert(c.size() == 4);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.modifiers/emplace_front.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.modifiers/emplace_front.pass.cpp
index 7f0298cdf28ad1ba33172fc0f91eb8e774047db3..43d6c36d2179b4a76b4df1aa9cec4ee819cc6e3b 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.modifiers/emplace_front.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.modifiers/emplace_front.pass.cpp
@@ -75,7 +75,7 @@ testN(int start, int N)
 }
 
 
-int main()
+int main(int, char**)
 {
     {
     int rng[] = {0, 1, 2, 3, 1023, 1024, 1025, 2047, 2048, 2049};
@@ -102,4 +102,6 @@ int main()
         c.emplace_front(1, 2, 3);
         assert(c.size() == 4);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.modifiers/erase_iter.invalidation.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.modifiers/erase_iter.invalidation.pass.cpp
index 3a055df9fee7048a71e366d2779b1e2443c844f4..54395114a0cd82616b13862daf36e8921ae391e9 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.modifiers/erase_iter.invalidation.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.modifiers/erase_iter.invalidation.pass.cpp
@@ -54,7 +54,7 @@ void del_at_end(C c)
     assert(&*it2 == &*it4);
 }
 
-int main()
+int main(int, char**)
 {
     std::deque<int> queue;
     for (int i = 0; i < 20; ++i)
@@ -66,4 +66,6 @@ int main()
         del_at_end(queue);
         queue.pop_back();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.modifiers/erase_iter.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.modifiers/erase_iter.pass.cpp
index 79cb562c1c5fe86f8457b9a11338a42876eab575..d8db68368b00af2894b96ca6b1344d37401539b4 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.modifiers/erase_iter.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.modifiers/erase_iter.pass.cpp
@@ -88,7 +88,7 @@ testN(int start, int N)
     }
 }
 
-int main()
+int main(int, char**)
 {
     {
     int rng[] = {0, 1, 2, 3, 1023, 1024, 1025, 2047, 2048, 2049};
@@ -121,4 +121,6 @@ int main()
     assert(v.size() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.modifiers/erase_iter_iter.invalidation.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.modifiers/erase_iter_iter.invalidation.pass.cpp
index fd08b6afec6b27e9f58f9d0bab84c5b330357b16..3a8a06d58cf4b3abcae8fcb730ee78fb171eb8d4 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.modifiers/erase_iter_iter.invalidation.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.modifiers/erase_iter_iter.invalidation.pass.cpp
@@ -59,7 +59,7 @@ void del_at_end(C c, size_t num)
 }
 
 
-int main()
+int main(int, char**)
 {
     std::deque<int> queue;
     for (int i = 0; i < 20; ++i)
@@ -74,4 +74,6 @@ int main()
         }
         queue.pop_back();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.modifiers/erase_iter_iter.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.modifiers/erase_iter_iter.pass.cpp
index c81d9a8bbac405a37a55c2753d8ce70053ce62a5..c738748a6f61f7747eed90989605caff09243fce 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.modifiers/erase_iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.modifiers/erase_iter_iter.pass.cpp
@@ -95,7 +95,7 @@ testN(int start, int N)
     }
 }
 
-int main()
+int main(int, char**)
 {
     {
     int rng[] = {0, 1, 2, 3, 1023, 1024, 1025, 2047, 2048, 2049};
@@ -127,4 +127,6 @@ int main()
     assert(v.size() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.modifiers/insert_iter_initializer_list.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.modifiers/insert_iter_initializer_list.pass.cpp
index f14da8a817b539a31a2a94387d39009dd8996e23..e0da02f7e7e6de6141d30f08785ac4ee85c3b7cf 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.modifiers/insert_iter_initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.modifiers/insert_iter_initializer_list.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::deque<int> d(10, 1);
@@ -59,4 +59,6 @@ int main()
     assert(d[12] == 1);
     assert(d[13] == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.modifiers/insert_iter_iter.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.modifiers/insert_iter_iter.pass.cpp
index cb36aa2802c700e39cd1f3fe80ca0fed9fde98f3..9a5f05476d393e8fc0e4d06a188419b32c50c553 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.modifiers/insert_iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.modifiers/insert_iter_iter.pass.cpp
@@ -259,7 +259,7 @@ test_move()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
     int rng[] = {0, 1, 2, 3, 1023, 1024, 1025, 2047, 2048, 2049};
@@ -285,4 +285,6 @@ int main()
     test_move<std::deque<MoveOnly, min_allocator<MoveOnly> > >();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.modifiers/insert_rvalue.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.modifiers/insert_rvalue.pass.cpp
index a9f242706c2c0682bac5342f04f13943decc37eb..eec8e0a499845e4f6d8e6f6e9aea1d87ddde8017 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.modifiers/insert_rvalue.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.modifiers/insert_rvalue.pass.cpp
@@ -91,7 +91,7 @@ testN(int start, int N)
     }
 }
 
-int main()
+int main(int, char**)
 {
     {
     int rng[] = {0, 1, 2, 3, 1023, 1024, 1025, 2047, 2048, 2049};
@@ -107,4 +107,6 @@ int main()
         for (int j = 0; j < N; ++j)
             testN<std::deque<MoveOnly, min_allocator<MoveOnly>> >(rng[i], rng[j]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.modifiers/insert_size_value.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.modifiers/insert_size_value.pass.cpp
index ced0e360ba1766ada9d793baee28991efdf991c3..0b95c8fc50a28910f33d449c7dc134d335ef8ae3 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.modifiers/insert_size_value.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.modifiers/insert_size_value.pass.cpp
@@ -132,7 +132,7 @@ self_reference_test()
     }
 }
 
-int main()
+int main(int, char**)
 {
     {
     int rng[] = {0, 1, 2, 3, 1023, 1024, 1025, 2047, 2048, 2049};
@@ -154,4 +154,6 @@ int main()
     self_reference_test<std::deque<int, min_allocator<int>> >();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.modifiers/insert_value.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.modifiers/insert_value.pass.cpp
index 2e16c342a72a6bd1c8b4528d0a8d35c64287244a..8dc0b50b570f18190a290d0788416c7a49d6aacf 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.modifiers/insert_value.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.modifiers/insert_value.pass.cpp
@@ -114,7 +114,7 @@ self_reference_test()
     }
 }
 
-int main()
+int main(int, char**)
 {
     {
     int rng[] = {0, 1, 2, 3, 1023, 1024, 1025, 2047, 2048, 2049};
@@ -134,4 +134,6 @@ int main()
     self_reference_test<std::deque<int, min_allocator<int>> >();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.modifiers/pop_back.invalidation.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.modifiers/pop_back.invalidation.pass.cpp
index 74c48d326f47382073b8bcd3e239d43d1a21f05b..7b5427b83686d904edca59b2fec28befd64afe23 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.modifiers/pop_back.invalidation.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.modifiers/pop_back.invalidation.pass.cpp
@@ -34,7 +34,7 @@ void test(C c)
     assert(&*it2 == &*it4);
 }
 
-int main()
+int main(int, char**)
 {
     std::deque<int> queue;
     for (int i = 0; i < 20; ++i)
@@ -45,4 +45,6 @@ int main()
         test(queue);
         queue.pop_back();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.modifiers/pop_back.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.modifiers/pop_back.pass.cpp
index 1eee65186aede0d2146706e263906e2e66e047ea..b0315eb54be810919e699c83a8f0855eb6f95185 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.modifiers/pop_back.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.modifiers/pop_back.pass.cpp
@@ -63,7 +63,7 @@ testN(int start, int N)
     }
 }
 
-int main()
+int main(int, char**)
 {
     {
     int rng[] = {0, 1, 2, 3, 1023, 1024, 1025, 2047, 2048, 2049};
@@ -81,4 +81,6 @@ int main()
             testN<std::deque<int, min_allocator<int>> >(rng[i], rng[j]);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.modifiers/pop_front.invalidation.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.modifiers/pop_front.invalidation.pass.cpp
index e773debde43faad9b3546008b9ce2c09edd5d15f..3ff1b5b9f176a3525f5b83812e0c21f828e475be 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.modifiers/pop_front.invalidation.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.modifiers/pop_front.invalidation.pass.cpp
@@ -34,7 +34,7 @@ void test(C c)
     assert(&*it2 == &*it4);
 }
 
-int main()
+int main(int, char**)
 {
     std::deque<int> queue;
     for (int i = 0; i < 20; ++i)
@@ -45,4 +45,6 @@ int main()
         test(queue);
         queue.pop_back();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.modifiers/pop_front.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.modifiers/pop_front.pass.cpp
index 672187380a45c239f22bd4d591eb2d6c7184bf0e..9d25d168492e805a1804d04126d52b6f03d0438b 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.modifiers/pop_front.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.modifiers/pop_front.pass.cpp
@@ -63,7 +63,7 @@ testN(int start, int N)
     }
 }
 
-int main()
+int main(int, char**)
 {
     {
     int rng[] = {0, 1, 2, 3, 1023, 1024, 1025, 2047, 2048, 2049};
@@ -81,4 +81,6 @@ int main()
             testN<std::deque<int, min_allocator<int>> >(rng[i], rng[j]);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.modifiers/push_back.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.modifiers/push_back.pass.cpp
index be2d72c53584e308f2ea1d12da3ccecc7a78b771..d0a73c37f9961ed8e7341f1dd33bc0bb1a78a956 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.modifiers/push_back.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.modifiers/push_back.pass.cpp
@@ -53,7 +53,7 @@ void test(int size)
     }
 }
 
-int main()
+int main(int, char**)
 {
     {
     int rng[] = {0, 1, 2, 3, 1023, 1024, 1025, 2046, 2047, 2048, 2049, 4094, 4095, 4096};
@@ -69,4 +69,6 @@ int main()
         test<std::deque<int, min_allocator<int>> >(rng[j]);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.modifiers/push_back_exception_safety.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.modifiers/push_back_exception_safety.pass.cpp
index 4bd62b1091902e5af1f567508d97c6323625559c..d4c46f0bcbc39fe32876ec90d36d44ec3524f651 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.modifiers/push_back_exception_safety.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.modifiers/push_back_exception_safety.pass.cpp
@@ -64,7 +64,7 @@ CMyClass::~CMyClass() {
 
 bool operator==(const CMyClass &lhs, const CMyClass &rhs) { return lhs.equal(rhs); }
 
-int main()
+int main(int, char**)
 {
     CMyClass instance(42);
     {
@@ -98,4 +98,6 @@ int main()
         assert(vec==vec2);
     }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.modifiers/push_back_rvalue.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.modifiers/push_back_rvalue.pass.cpp
index aa9366956ff46896f6136c3bc9e7f0e79bb696c5..29354468134c1c6d65c0629566a0a107629d8614 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.modifiers/push_back_rvalue.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.modifiers/push_back_rvalue.pass.cpp
@@ -58,7 +58,7 @@ void test(int size)
 }
 
 
-int main()
+int main(int, char**)
 {
     {
     int rng[] = {0, 1, 2, 3, 1023, 1024, 1025, 2046, 2047, 2048, 2049, 4094, 4095, 4096};
@@ -72,4 +72,6 @@ int main()
     for (int j = 0; j < N; ++j)
         test<std::deque<MoveOnly, min_allocator<MoveOnly>> >(rng[j]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.modifiers/push_front.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.modifiers/push_front.pass.cpp
index 7e4f7151c5496ef673fb7f63d007b291f738e867..dee483c7957100df11195d412f117ba33dd1c062 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.modifiers/push_front.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.modifiers/push_front.pass.cpp
@@ -62,7 +62,7 @@ testN(int start, int N)
     test(c1, -10);
 }
 
-int main()
+int main(int, char**)
 {
     {
     int rng[] = {0, 1, 2, 3, 1023, 1024, 1025, 2047, 2048, 2049};
@@ -80,4 +80,6 @@ int main()
             testN<std::deque<int, min_allocator<int>> >(rng[i], rng[j]);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.modifiers/push_front_exception_safety.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.modifiers/push_front_exception_safety.pass.cpp
index a6a5200e9a8f36622268b5d88fba28f30622a535..103f2c41d58f7aa1578c33b58aac1c7fc0e23e3c 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.modifiers/push_front_exception_safety.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.modifiers/push_front_exception_safety.pass.cpp
@@ -64,7 +64,7 @@ CMyClass::~CMyClass() {
 
 bool operator==(const CMyClass &lhs, const CMyClass &rhs) { return lhs.equal(rhs); }
 
-int main()
+int main(int, char**)
 {
     CMyClass instance(42);
     {
@@ -98,4 +98,6 @@ int main()
         assert(vec==vec2);
     }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.modifiers/push_front_rvalue.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.modifiers/push_front_rvalue.pass.cpp
index 3ffde9bf34f59e70f87193844ff4b4d84eff8265..7a66554d12701831ae7262270a4d85c4cafd54aa 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.modifiers/push_front_rvalue.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.modifiers/push_front_rvalue.pass.cpp
@@ -67,7 +67,7 @@ testN(int start, int N)
 }
 
 
-int main()
+int main(int, char**)
 {
     {
     int rng[] = {0, 1, 2, 3, 1023, 1024, 1025, 2047, 2048, 2049};
@@ -83,4 +83,6 @@ int main()
         for (int j = 0; j < N; ++j)
             testN<std::deque<MoveOnly, min_allocator<MoveOnly>> >(rng[i], rng[j]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.special/copy.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.special/copy.pass.cpp
index f6ee7737d83ae8b461a7e47ddc772247c1df0449..f861c424af4bdf89be701e88083de786e086c13c 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.special/copy.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.special/copy.pass.cpp
@@ -66,7 +66,7 @@ void testN(int start, int N)
     assert(c1 == c2);
 }
 
-int main()
+int main(int, char**)
 {
     {
     int rng[] = {0, 1, 2, 3, 1023, 1024, 1025, 2047, 2048, 2049};
@@ -84,4 +84,6 @@ int main()
             testN<std::deque<int, min_allocator<int>> >(rng[i], rng[j]);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.special/copy_backward.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.special/copy_backward.pass.cpp
index 2e51d13ce7081d49bd2d592a393093c1dd324351..b5225ae71bc896d7635710cdfef1bd7a3027f448 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.special/copy_backward.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.special/copy_backward.pass.cpp
@@ -65,7 +65,7 @@ void testN(int start, int N)
     assert(c1 == c2);
 }
 
-int main()
+int main(int, char**)
 {
     {
     int rng[] = {0, 1, 2, 3, 1023, 1024, 1025, 2047, 2048, 2049};
@@ -83,4 +83,6 @@ int main()
             testN<std::deque<int, min_allocator<int>> >(rng[i], rng[j]);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.special/move.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.special/move.pass.cpp
index d26132b3f65d40493244c402c97d1ad71fab41d0..d1c2a3d726a2600f98d0000a992e375bb8b56e42 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.special/move.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.special/move.pass.cpp
@@ -65,7 +65,7 @@ void testN(int start, int N)
     assert(c1 == c2);
 }
 
-int main()
+int main(int, char**)
 {
     {
     int rng[] = {0, 1, 2, 3, 1023, 1024, 1025, 2047, 2048, 2049};
@@ -83,4 +83,6 @@ int main()
             testN<std::deque<int, min_allocator<int>> >(rng[i], rng[j]);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.special/move_backward.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.special/move_backward.pass.cpp
index 0f3ab067fc5bdc370da85cd574662ca05047f213..9193609d200cd31cd25e9126f6f140889b8eb397 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.special/move_backward.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.special/move_backward.pass.cpp
@@ -65,7 +65,7 @@ void testN(int start, int N)
     assert(c1 == c2);
 }
 
-int main()
+int main(int, char**)
 {
     {
     int rng[] = {0, 1, 2, 3, 1023, 1024, 1025, 2047, 2048, 2049};
@@ -83,4 +83,6 @@ int main()
             testN<std::deque<int, min_allocator<int> > >(rng[i], rng[j]);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.special/swap.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.special/swap.pass.cpp
index 56310b80ce8e8aa177738187e4e762469c876341..33910e419b73bb9580837f1fc70990dee61d19c6 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.special/swap.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.special/swap.pass.cpp
@@ -50,7 +50,7 @@ void testN(int start, int N, int M)
     assert(c2 == c1_save);
 }
 
-int main()
+int main(int, char**)
 {
     {
         int rng[] = {0, 1, 2, 3, 1023, 1024, 1025, 2047, 2048, 2049};
@@ -106,4 +106,6 @@ int main()
         assert(c2.get_allocator() == A());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.special/swap_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.special/swap_noexcept.pass.cpp
index 7820480da5f14f2b0f35947552d57ca794b4a654..edbe21128956c6052dc05bac56e9ed7c2e634224 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.special/swap_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.special/swap_noexcept.pass.cpp
@@ -52,7 +52,7 @@ struct some_alloc2
     typedef std::true_type is_always_equal;
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::deque<MoveOnly> C;
@@ -85,4 +85,6 @@ int main()
     }
 #endif
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/iterators.pass.cpp b/libcxx/test/std/containers/sequences/deque/iterators.pass.cpp
index 9fe9326ec90541459b25bd99143953cb768d4841..1f06ffde41ac2da24349a7327751a5abc16e0374 100644
--- a/libcxx/test/std/containers/sequences/deque/iterators.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/iterators.pass.cpp
@@ -22,7 +22,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::deque<int> C;
@@ -76,4 +76,6 @@ int main()
 //         assert ( ii1 != c.end());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/deque/types.pass.cpp b/libcxx/test/std/containers/sequences/deque/types.pass.cpp
index 1310400922f95251a2f8108ec93e3f54477a838a..cfab930f390d911c37ab736e601e6774bd1894fe 100644
--- a/libcxx/test/std/containers/sequences/deque/types.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/types.pass.cpp
@@ -71,7 +71,7 @@ test()
         typename std::iterator_traits<typename C::const_iterator>::difference_type>::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     test<int, test_allocator<int> >();
     test<int*, std::allocator<int*> >();
@@ -100,4 +100,6 @@ int main()
             typename std::iterator_traits<typename C::const_iterator>::difference_type>::value), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/allocator_mismatch.fail.cpp b/libcxx/test/std/containers/sequences/forwardlist/allocator_mismatch.fail.cpp
index 6973d9aee3aafc2bcf97d3ddb4336e277d10c839..42fb8da918de326e1f21fe057b3ed967bfbe8f10 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/allocator_mismatch.fail.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/allocator_mismatch.fail.cpp
@@ -11,7 +11,9 @@
 
 #include <forward_list>
 
-int main()
+int main(int, char**)
 {
     std::forward_list<int, std::allocator<long> > fl;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/empty.fail.cpp b/libcxx/test/std/containers/sequences/forwardlist/empty.fail.cpp
index effcc27335bc9bd39e83bab1ec2d2e24998a38c2..2ca3e024e661ab06d6e8fc7522b9e8ee5d73c742 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/empty.fail.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/empty.fail.cpp
@@ -20,8 +20,10 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     std::forward_list<int> c;
     c.empty();  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/empty.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/empty.pass.cpp
index 6597c66ea29c33c0c7af4bb49500aa0d34faec99..727904c9871338a3a564ea71a93c40f10a9e8b44 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/empty.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/empty.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::forward_list<int> C;
@@ -42,4 +42,6 @@ int main()
     assert(c.empty());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.access/front.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.access/front.pass.cpp
index 26bbdb61e6e3f8d94245811b5cb84f4214e126ca..2509e9b2c4fa4d790706d23efcd838d4b2b0dc49 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.access/front.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.access/front.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -57,4 +57,6 @@ int main()
         assert(*c.begin() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/alloc.fail.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/alloc.fail.cpp
index 2057286589c87e18b1daf83366241345b634a889..bf43ee82ca069ccf815130ca908553aba9fcf968 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/alloc.fail.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/alloc.fail.cpp
@@ -16,7 +16,7 @@
 #include "test_allocator.h"
 #include "../../../NotConstructible.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef test_allocator<NotConstructible> A;
@@ -26,4 +26,6 @@ int main()
         assert(c.get_allocator() == A(12));
         assert(c.empty());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/alloc.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/alloc.pass.cpp
index b70b4e8a2899518408d32afdb6f623e5c2a5b585..c362e20515307348e69fc786158d164c3c1fff21 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/alloc.pass.cpp
@@ -17,7 +17,7 @@
 #include "../../../NotConstructible.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef test_allocator<NotConstructible> A;
@@ -45,4 +45,6 @@ int main()
         assert(c.empty());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/assign_copy.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/assign_copy.pass.cpp
index 05a74d50df0f2bbb08ec2e7f0ec835d5c11d8d0d..e40d405c9328c03104ad5a52fd4b399b05ed5556 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/assign_copy.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/assign_copy.pass.cpp
@@ -17,7 +17,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -142,4 +142,6 @@ int main()
         assert(c1.get_allocator() == A());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/assign_init.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/assign_init.pass.cpp
index 20ed6c51a8a19691bf2974cfa4422b7fe7eb657a..40405dd2e7374578eb849ff8a72841f062dc7cb9 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/assign_init.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/assign_init.pass.cpp
@@ -18,7 +18,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -64,4 +64,6 @@ int main()
             assert(*i == 10+n);
         assert(n == 4);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/assign_move.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/assign_move.pass.cpp
index 24feee382edb56d5535ce446b1731422181c9d6d..36e4ea0ca0c5b3e1149203f4f3a0de23fefb638d 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/assign_move.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/assign_move.pass.cpp
@@ -20,7 +20,7 @@
 #include "MoveOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef MoveOnly T;
@@ -193,4 +193,6 @@ int main()
         assert(c1.get_allocator() == A());
         assert(c0.empty());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/assign_op_init.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/assign_op_init.pass.cpp
index 42f0a43b93297e47a55dd06bd8e41aeb6a97ebab..14c098b660b0ea82b0358ac859b02bab0dfa1489 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/assign_op_init.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/assign_op_init.pass.cpp
@@ -18,7 +18,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -64,4 +64,6 @@ int main()
             assert(*i == 10+n);
         assert(n == 4);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/assign_range.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/assign_range.pass.cpp
index 098702b4407665d04ffc37a1ab36e48c6868c8b2..c0b934445e0a5a209a0000e72d7a47af9c822cf7 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/assign_range.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/assign_range.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_iterators.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -74,4 +74,6 @@ int main()
         assert(n == 4);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/assign_size_value.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/assign_size_value.pass.cpp
index ec8aadf38c78bc7daa486c5f9c65dc41c40b53b8..ea4cc811e4bfa9180dcd00f276af2226778b816b 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/assign_size_value.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/assign_size_value.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -64,4 +64,6 @@ int main()
         assert(n == 4);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/copy.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/copy.pass.cpp
index 551eebb440c8d293d033642c035903371bf57a00..681629a2c5e34838a8bae95b91a6f2a19802d062 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/copy.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/copy.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -64,4 +64,6 @@ int main()
         assert(c.get_allocator() == A());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/copy_alloc.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/copy_alloc.pass.cpp
index bfcb2b4905299e95de48e7b00d70457aec51876b..9788ca5ff6bac5d2607ec9f428d33062fbc46bdf 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/copy_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/copy_alloc.pass.cpp
@@ -17,7 +17,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -63,4 +63,6 @@ int main()
         assert(c.get_allocator() == A());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/deduct.fail.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/deduct.fail.cpp
index 9c91a031f99198410f2e9a86bec79fa2b003bc71..cc146316ac1d7b5e46e638ef8b26acb4feae6fc0 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/deduct.fail.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/deduct.fail.cpp
@@ -25,7 +25,7 @@
 
 struct A {};
 
-int main()
+int main(int, char**)
 {
 //  Test the explicit deduction guides
 
@@ -38,4 +38,6 @@ int main()
 //      forward_list<allocator<int>, allocator<allocator<int>>>
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/deduct.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/deduct.pass.cpp
index e4599d469ea033a50b91df4281ea548a986b2565..fd49de5814e62238ff11146d7b0ea433cb73f3a2 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/deduct.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/deduct.pass.cpp
@@ -29,7 +29,7 @@
 
 struct A {};
 
-int main()
+int main(int, char**)
 {
 
 //  Test the explicit deduction guides
@@ -99,4 +99,6 @@ int main()
     static_assert(std::is_same_v<decltype(fwl)::allocator_type, std::allocator<long double>>, "");
     assert(std::distance(fwl.begin(), fwl.end()) == 0); // no size for forward_list
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/default.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/default.pass.cpp
index 27eb1577c448ba2daaa76c022db4b1a66a403f3d..1694faf466b248c2a6268f3f8ac992952a0d353d 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/default.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/default.pass.cpp
@@ -15,7 +15,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -37,4 +37,6 @@ int main()
         assert(c.empty());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/default_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/default_noexcept.pass.cpp
index 9926369164645ef56e19e978b7d050f4bde48678..f9363feb67b71c2c0bc0d4ba191a320543b3ed32 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/default_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/default_noexcept.pass.cpp
@@ -29,7 +29,7 @@ struct some_alloc
     some_alloc(const some_alloc&);
 };
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -49,4 +49,6 @@ int main()
         typedef std::forward_list<MoveOnly, some_alloc<MoveOnly>> C;
         static_assert(!std::is_nothrow_default_constructible<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/default_recursive.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/default_recursive.pass.cpp
index ab61b04f93e0f6730877bd8ff727bb5806ca3784..98b120f5350b929372faa8f193a56ebaed63501e 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/default_recursive.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/default_recursive.pass.cpp
@@ -19,6 +19,8 @@ struct X
     std::forward_list<X> q;
 };
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/dtor_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/dtor_noexcept.pass.cpp
index ce3d0f4379d6b75b282241a24c5f75147ace7743..ba879964554abc67bb4b7765cabc628e7af1d8d0 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/dtor_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/dtor_noexcept.pass.cpp
@@ -27,7 +27,7 @@ struct some_alloc
     ~some_alloc() noexcept(false);
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::forward_list<MoveOnly> C;
@@ -47,4 +47,6 @@ int main()
         static_assert(!std::is_nothrow_destructible<C>::value, "");
     }
 #endif // _LIBCPP_VERSION
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/init.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/init.pass.cpp
index ac4bcf4a518f6dba5dee83362449c6bbe4a69288..fda636073a8f4a0f2f487fc3ce3a94adee5e5b0b 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/init.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/init.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -37,4 +37,6 @@ int main()
             assert(*i == n);
         assert(n == 10);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/init_alloc.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/init_alloc.pass.cpp
index 05a31877834a6a144bdb1485c1eaf85122baeb06..cdef7c07ef5dfde966dea0abfdd23355b508b699 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/init_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/init_alloc.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -42,4 +42,6 @@ int main()
         assert(n == 10);
         assert(c.get_allocator() == A());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/move.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/move.pass.cpp
index 428fa04f1480730c0701a9bc6bc0ec90e3cded68..eedec348783bcf768e7e525a8181258b4bb91dee 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/move.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/move.pass.cpp
@@ -20,7 +20,7 @@
 #include "MoveOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef MoveOnly T;
@@ -67,4 +67,6 @@ int main()
         assert(c0.empty());
         assert(c.get_allocator() == A());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/move_alloc.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/move_alloc.pass.cpp
index 9337b9b0548e115b18c6b79a577ea264d9824402..7db6a41e85e7263baa36ba52208385120a4456f1 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/move_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/move_alloc.pass.cpp
@@ -20,7 +20,7 @@
 #include "MoveOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef MoveOnly T;
@@ -67,4 +67,6 @@ int main()
         assert(c0.empty());
         assert(c.get_allocator() == A());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/move_assign_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/move_assign_noexcept.pass.cpp
index 502ca930e599c3c60513c8bf9ff389a2b1e59d13..486c124af650b60d5583b7e9225d4d8eeef8fd3f 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/move_assign_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/move_assign_noexcept.pass.cpp
@@ -31,7 +31,7 @@ struct some_alloc
     some_alloc(const some_alloc&);
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::forward_list<MoveOnly> C;
@@ -51,4 +51,6 @@ int main()
         static_assert(!std::is_nothrow_move_assignable<C>::value, "");
     }
 #endif // _LIBCPP_VERSION
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/move_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/move_noexcept.pass.cpp
index ddd3cfe732713a984195ad2baa7e023cb45248cc..5717bb8911895ce7c6aff87a859c06f0dfa6fd4d 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/move_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/move_noexcept.pass.cpp
@@ -29,7 +29,7 @@ struct some_alloc
     some_alloc(const some_alloc&);
 };
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -49,4 +49,6 @@ int main()
         static_assert(!std::is_nothrow_move_constructible<C>::value, "");
     }
 #endif // _LIBCPP_VERSION
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/range.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/range.pass.cpp
index fb0ec74d6ebfc375af0413d8f9b2e00cb7b88a69..ce9cd59d1a3ad8e16b2edf35e3a9dfd2fa420e51 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/range.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/range.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_iterators.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -44,4 +44,6 @@ int main()
         assert(n == std::end(t) - std::begin(t));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/range_alloc.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/range_alloc.pass.cpp
index 30fe467fdeaa136b1d2aaf0fcb231c7cadc34833..1a85d3feebec5438b6aadfde951bd1748b2deea7 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/range_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/range_alloc.pass.cpp
@@ -20,7 +20,7 @@
 #include "test_iterators.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -50,4 +50,6 @@ int main()
         assert(c.get_allocator() == A());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/size.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/size.pass.cpp
index 7514d263ed1a2baa6d90d7b38076c29e0a3c7c84..ca3931d107d55937b57808bac883b637334d6ade 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/size.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/size.pass.cpp
@@ -33,7 +33,7 @@ void check_allocator(unsigned n, Allocator const &alloc = Allocator())
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     { // test that the ctor is explicit
       typedef std::forward_list<DefaultOnly> C;
@@ -70,4 +70,6 @@ int main()
         check_allocator<T, min_allocator<T>> ( 3 );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/size_value.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/size_value.pass.cpp
index eee26298e3373f4bb1aa0c076adef43ec867a7ef..e3f247202d430f37a7b35f9a7aba3387b7e7baab 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/size_value.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/size_value.pass.cpp
@@ -15,7 +15,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -41,4 +41,6 @@ int main()
         assert(n == N);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/size_value_alloc.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/size_value_alloc.pass.cpp
index 26b3f8c6f58f132dc8fc24cfc923308884efd9c7..cc5394f5ab382cafdea7c2afa0a0e158fccce9d0 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/size_value_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.cons/size_value_alloc.pass.cpp
@@ -16,7 +16,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef test_allocator<int> A;
@@ -46,4 +46,6 @@ int main()
         assert(c.get_allocator() == A());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.erasure/erase.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.erasure/erase.pass.cpp
index 53e99b48c284ef2552c348c7954193c364aaf50c..68a26fbc704ff8c128be0ea61f5d75efdbd98e5a 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.erasure/erase.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.erasure/erase.pass.cpp
@@ -66,7 +66,7 @@ void test()
     test0(S({1,2,1}), opt(3), S({1,2,1}));
 }
 
-int main()
+int main(int, char**)
 {
     test<std::forward_list<int>>();
     test<std::forward_list<int, min_allocator<int>>> ();
@@ -74,4 +74,6 @@ int main()
 
     test<std::forward_list<long>>();
     test<std::forward_list<double>>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.erasure/erase_if.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.erasure/erase_if.pass.cpp
index e3e8575403e8e36bf05db15e24bdafb5736a56d8..b2106b8c8de455f5c80a0c9faba86594cc780606 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.erasure/erase_if.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.erasure/erase_if.pass.cpp
@@ -66,7 +66,7 @@ void test()
     test0(S({1,2,3}), False, S({1,2,3}));
 }
 
-int main()
+int main(int, char**)
 {
     test<std::forward_list<int>>();
     test<std::forward_list<int, min_allocator<int>>> ();
@@ -74,4 +74,6 @@ int main()
 
     test<std::forward_list<long>>();
     test<std::forward_list<double>>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.iter/before_begin.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.iter/before_begin.pass.cpp
index 726051b8e0f4abc9c631cecf4ffe1176f732acf2..638a78327df0d1a9ec48eee0b5f573aef1767cdf 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.iter/before_begin.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.iter/before_begin.pass.cpp
@@ -18,7 +18,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -100,4 +100,6 @@ int main()
         assert(std::distance(i, c.end()) == 11);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.iter/iterators.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.iter/iterators.pass.cpp
index 25c2c312bf4b47bf81a2bf2ac689db8cbed608fc..e5441109bf37336abdf9563435fd2f94ff1fe2c0 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.iter/iterators.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.iter/iterators.pass.cpp
@@ -22,7 +22,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -142,4 +142,6 @@ int main()
 //         assert ( ii1 != c.end());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/clear.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/clear.pass.cpp
index 5f7ac62c445d558896640a7d9f50d4f5dd280bd9..8ed29ec5afd30af67ed29c239a9e3cd3f98ff400 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/clear.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/clear.pass.cpp
@@ -17,7 +17,7 @@
 #include "../../../NotConstructible.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef NotConstructible T;
@@ -63,4 +63,6 @@ int main()
         assert(distance(c.begin(), c.end()) == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/emplace_after.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/emplace_after.pass.cpp
index 70e7d248fadcf8a192f5e2479c7dcc9dda2edd71..f2581239824ae2af1377133b7ceecd924a465f88 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/emplace_after.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/emplace_after.pass.cpp
@@ -19,7 +19,7 @@
 #include "../../../Emplaceable.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef Emplaceable T;
@@ -83,4 +83,6 @@ int main()
         assert(*next(c.begin(), 3) == Emplaceable(2, 3.5));
         assert(distance(c.begin(), c.end()) == 4);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/emplace_front.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/emplace_front.pass.cpp
index 121e0178c1c881adbc2dad37e79d943931d64a1c..1669e0c5c12a34e7fa5982077cfaca3b6e4aa8bd 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/emplace_front.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/emplace_front.pass.cpp
@@ -21,7 +21,7 @@
 #include "../../../Emplaceable.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef Emplaceable T;
@@ -67,4 +67,6 @@ int main()
         assert(*next(c.begin()) == Emplaceable());
         assert(distance(c.begin(), c.end()) == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/erase_after_many.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/erase_after_many.pass.cpp
index 419ce6891d46efd24da0ff756dc5730e639b1081..0a431a8965d46b5750518348cd0f588218fb9f52 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/erase_after_many.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/erase_after_many.pass.cpp
@@ -15,7 +15,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -151,4 +151,6 @@ int main()
         assert(distance(c.begin(), c.end()) == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/erase_after_one.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/erase_after_one.pass.cpp
index 563be1739b1e46ec8f27bc1e370ea7669fd3ca8b..59e687f6c4c3dc003ef87cafb4646463327ad228 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/erase_after_one.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/erase_after_one.pass.cpp
@@ -15,7 +15,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -93,4 +93,6 @@ int main()
         assert(distance(c.begin(), c.end()) == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/insert_after_const.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/insert_after_const.pass.cpp
index bfc8c04f19f24dfe8c06a5f8a61ae48bb04b619d..3ba4f9e23f190100540132991d2f5cff483a61e8 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/insert_after_const.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/insert_after_const.pass.cpp
@@ -15,7 +15,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -83,4 +83,6 @@ int main()
         assert(distance(c.begin(), c.end()) == 4);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/insert_after_init.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/insert_after_init.pass.cpp
index 1782bc7fdc0ef44c7817be92a8855a5a7f69a81f..be5c6e5176cf2f3d696487b54a70f34e5135bfbe 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/insert_after_init.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/insert_after_init.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -69,4 +69,6 @@ int main()
         assert(*next(c.begin(), 3) == 1);
         assert(*next(c.begin(), 4) == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/insert_after_range.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/insert_after_range.pass.cpp
index 8ad42aced00fd0069ed748603a0a5263854ea184..4cbc92edd7437b61bb2a74146dbcf90f54413c8c 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/insert_after_range.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/insert_after_range.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_iterators.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -76,4 +76,6 @@ int main()
         assert(*next(c.begin(), 4) == 2);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/insert_after_rv.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/insert_after_rv.pass.cpp
index 2aa254bbf6a30295498d3d55e7307b40b7255dbb..2495a707a98293ee74241559899343e25fae388a 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/insert_after_rv.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/insert_after_rv.pass.cpp
@@ -18,7 +18,7 @@
 #include "MoveOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef MoveOnly T;
@@ -84,4 +84,6 @@ int main()
         assert(*next(c.begin(), 3) == 2);
         assert(distance(c.begin(), c.end()) == 4);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/insert_after_size_value.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/insert_after_size_value.pass.cpp
index e1927945af15a3937248bbb7ac709569e76898fc..7898fea9219ad5217d9c2dc9a97f4b3e15fd6325 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/insert_after_size_value.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/insert_after_size_value.pass.cpp
@@ -15,7 +15,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -69,4 +69,6 @@ int main()
         assert(*next(c.begin(), 4) == 3);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/pop_front.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/pop_front.pass.cpp
index 40b092e7697d91fb92f88d573d5c247e273fefb8..d28f10e81923b2ed889f4f4031e434997c0a7b6d 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/pop_front.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/pop_front.pass.cpp
@@ -16,7 +16,7 @@
 #include "MoveOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -70,4 +70,6 @@ int main()
         assert(distance(c.begin(), c.end()) == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/push_front_const.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/push_front_const.pass.cpp
index 15e3bfbc18468c5dffbbe7760ebeb34279b846f5..192227ee2b11d1f329dbf93d238f777d563bd1a2 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/push_front_const.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/push_front_const.pass.cpp
@@ -15,7 +15,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -43,4 +43,6 @@ int main()
         assert(distance(c.begin(), c.end()) == 2);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/push_front_exception_safety.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/push_front_exception_safety.pass.cpp
index 3015abb76db6831dee303b0b5238c219bf1d62c5..8b122f1f937beb1fda4c13c8abd4d9e462def4fa 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/push_front_exception_safety.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/push_front_exception_safety.pass.cpp
@@ -57,7 +57,7 @@ CMyClass::~CMyClass() {
     assert(fMagicValue == kFinishedConstructionMagicValue);
 }
 
-int main()
+int main(int, char**)
 {
     CMyClass instance;
     std::forward_list<CMyClass> vec;
@@ -70,4 +70,6 @@ int main()
     }
     catch (...) {
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/push_front_rv.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/push_front_rv.pass.cpp
index e768cd0aec30f7d72f7e2b6f4a081bfd02385d32..268101671cb556b55a54a0149530d842dfb3cabb 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/push_front_rv.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/push_front_rv.pass.cpp
@@ -18,7 +18,7 @@
 #include "MoveOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef MoveOnly T;
@@ -44,4 +44,6 @@ int main()
         assert(*next(c.begin()) == 1);
         assert(distance(c.begin(), c.end()) == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/resize_size.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/resize_size.pass.cpp
index b79e4fd36e7d93097eee18ec75ce69f54f60d890..ed2de980072939203d8152d9c3d62a76a2d598a4 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/resize_size.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/resize_size.pass.cpp
@@ -16,7 +16,7 @@
 #include "DefaultOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef DefaultOnly T;
@@ -110,4 +110,6 @@ int main()
         assert(*next(c.begin(), 5) == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/resize_size_value.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/resize_size_value.pass.cpp
index 30f99ab9670e4029c91fef8c105127864349b3a6..f6f4027e0fc6680fefa7c9eb7597a4544ac5971b 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/resize_size_value.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/resize_size_value.pass.cpp
@@ -21,7 +21,7 @@
 #include "container_test_types.h"
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -98,4 +98,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/merge.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/merge.pass.cpp
index c2e32a754ee9530cf0fceca75ebfa37937903c78..5a55ae963de36bcb22a75057bf78bee77aae8620 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/merge.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/merge.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -44,4 +44,6 @@ int main()
         assert(c1 == c3);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/merge_pred.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/merge_pred.pass.cpp
index 6656f9191ae1aa60991ba669514fd26c3c684348..3de61a37f7253f121ca19517fcfa22df01daa298 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/merge_pred.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/merge_pred.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -45,4 +45,6 @@ int main()
         assert(c1 == c3);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/remove.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/remove.pass.cpp
index fec75668a65612aa913887dd2d922cd98882fafb..ca3ec253da326bedcf6de424b4bc99125fd47447 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/remove.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/remove.pass.cpp
@@ -27,7 +27,7 @@ struct S {
     };
 
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -151,4 +151,6 @@ int main()
         assert(c1 == c2);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/remove_if.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/remove_if.pass.cpp
index 45a12e7e86482217590d4a18230dc30ec9b126d2..1b18337bc993465043de06d383a1195467e946ef 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/remove_if.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/remove_if.pass.cpp
@@ -24,7 +24,7 @@ bool g(int i)
     return i < 3;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -152,4 +152,6 @@ int main()
         assert(cp.count() == static_cast<std::size_t>(std::distance(std::begin(t1), std::end(t1))));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/reverse.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/reverse.pass.cpp
index e9fe3cae68ac1408392073588ba319b002248649..82b6813fff082280cfdb983d32e69b15401b93be 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/reverse.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/reverse.pass.cpp
@@ -30,7 +30,7 @@ void test(int N)
         assert(*j == i);
 }
 
-int main()
+int main(int, char**)
 {
     for (int i = 0; i < 10; ++i)
         test<std::forward_list<int> >(i);
@@ -38,4 +38,6 @@ int main()
     for (int i = 0; i < 10; ++i)
         test<std::forward_list<int, min_allocator<int>> >(i);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/sort.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/sort.pass.cpp
index 239e5f129d6780ee88f5667b58748ef8293496bb..c76fe03ec1a32bf76e95061d2cb57eda4ed6af05 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/sort.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/sort.pass.cpp
@@ -38,7 +38,7 @@ void test(int N)
         assert(*j == i);
 }
 
-int main()
+int main(int, char**)
 {
     for (int i = 0; i < 40; ++i)
         test<std::forward_list<int> >(i);
@@ -46,4 +46,6 @@ int main()
     for (int i = 0; i < 40; ++i)
         test<std::forward_list<int, min_allocator<int>> >(i);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/sort_pred.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/sort_pred.pass.cpp
index d7e127bf4813253f0852a8573db0e61edfd0c411..971508ac4103d44fa7125ec8591baa0148ea66a1 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/sort_pred.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/sort_pred.pass.cpp
@@ -39,7 +39,7 @@ void test(int N)
         assert(*j == N-1-i);
 }
 
-int main()
+int main(int, char**)
 {
     for (int i = 0; i < 40; ++i)
         test<std::forward_list<int> >(i);
@@ -47,4 +47,6 @@ int main()
     for (int i = 0; i < 40; ++i)
         test<std::forward_list<int, min_allocator<int>> >(i);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/splice_after_flist.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/splice_after_flist.pass.cpp
index 6b57b3189749e9b09d623f3536f8f5ae93e93573..e883aee2ce4beb42e0ed5f248fb602ad33ef8269 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/splice_after_flist.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/splice_after_flist.pass.cpp
@@ -38,7 +38,7 @@ testd(const C& c, int p, int l)
     assert(distance(c.begin(), c.end()) == size_t1 + l);
 }
 
-int main()
+int main(int, char**)
 {
     {
     // splicing different containers
@@ -72,4 +72,6 @@ int main()
     }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/splice_after_one.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/splice_after_one.pass.cpp
index a192627d8d18c4e21b0d8fad56641000ca957321..87b2f60e1ad048bc66e474603e425793fbb5efc8 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/splice_after_one.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/splice_after_one.pass.cpp
@@ -75,7 +75,7 @@ tests(const C& c, int p, int f)
     assert(distance(c.begin(), c.end()) == size_t1);
 }
 
-int main()
+int main(int, char**)
 {
     {
     // splicing different containers
@@ -137,4 +137,6 @@ int main()
     }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/splice_after_range.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/splice_after_range.pass.cpp
index c836a8bfe61420f654b89b86c53f34a005dcfd15..32050076c036664d2bfe33f35744665a5081a201 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/splice_after_range.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/splice_after_range.pass.cpp
@@ -75,7 +75,7 @@ tests(const C& c, int p, int f, int l)
     assert(distance(c.begin(), c.end()) == size_t1);
 }
 
-int main()
+int main(int, char**)
 {
     {
     // splicing different containers
@@ -165,4 +165,6 @@ int main()
     }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/unique.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/unique.pass.cpp
index ccb0f9a8631abc45e583a9b5d48cef2eaf882e36..07a4eae97b0d61482a54ca1fbcab5e04463dbb92 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/unique.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/unique.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -116,4 +116,6 @@ int main()
         assert(c1 == c2);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/unique_pred.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/unique_pred.pass.cpp
index 1d4a9a0f3ce95568908a3bd7b448ab4905daa02e..87db88080fc9814fd467810b1165a54d4f76b386 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/unique_pred.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/unique_pred.pass.cpp
@@ -21,7 +21,7 @@ bool g(int x, int y)
     return x == y;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -121,4 +121,6 @@ int main()
         assert(c1 == c2);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.spec/equal.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.spec/equal.pass.cpp
index 9f01fed66465a373455e6ea4b37a1b92485608d8..a727487ed0d9c530045b05c07efc0b1534eb4863 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.spec/equal.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.spec/equal.pass.cpp
@@ -47,7 +47,7 @@ void test(int N, int M)
     }
 }
 
-int main()
+int main(int, char**)
 {
     for (int i = 0; i < 10; ++i)
         for (int j = 0; j < 10; ++j)
@@ -57,4 +57,6 @@ int main()
         for (int j = 0; j < 10; ++j)
             test<std::forward_list<int, min_allocator<int>> >(i, j);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.spec/member_swap.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.spec/member_swap.pass.cpp
index 242a00bd8608982ffa7c652060e0e03d01be8b80..5e0438c62bfe414dd712c08226fdc68621e0dc4c 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.spec/member_swap.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.spec/member_swap.pass.cpp
@@ -17,7 +17,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -256,4 +256,6 @@ int main()
         assert(c2.get_allocator() == A());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.spec/non_member_swap.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.spec/non_member_swap.pass.cpp
index 44820d9d304e847acae7aaf3d9fa275ee129f26d..5b9b590d5551288880d6d55a011a996b6f459aed 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.spec/non_member_swap.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.spec/non_member_swap.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -257,4 +257,6 @@ int main()
         assert(c2.get_allocator() == A());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.spec/relational.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.spec/relational.pass.cpp
index e65e064ffdafc869395afbd604f8d68bc7fe888e..29a180a9661242bd63c453e8307b621157a5cf15 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.spec/relational.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.spec/relational.pass.cpp
@@ -52,7 +52,7 @@ void test(int N, int M)
         assert(c1 > c2);
 }
 
-int main()
+int main(int, char**)
 {
     for (int i = 0; i < 10; ++i)
         for (int j = 0; j < 10; ++j)
@@ -62,4 +62,6 @@ int main()
         for (int j = 0; j < 10; ++j)
             test<std::forward_list<int, min_allocator<int>> >(i, j);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.spec/swap_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.spec/swap_noexcept.pass.cpp
index ae48d1a4b95c5c5b16c46d867cbfc207f1a8fa36..6247954958457b00908e5c89604a0e9542d520c2 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.spec/swap_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.spec/swap_noexcept.pass.cpp
@@ -53,7 +53,7 @@ struct some_alloc2
     typedef std::true_type is_always_equal;
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::forward_list<MoveOnly> C;
@@ -85,4 +85,6 @@ int main()
         static_assert( noexcept(swap(std::declval<C&>(), std::declval<C&>())), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/incomplete.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/incomplete.pass.cpp
index fd789b8c895ff7deef8f84b1fa9e442beb119b2e..2bdfad777e8dfb190a71b22fb9b32517838aeaa8 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/incomplete.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/incomplete.pass.cpp
@@ -33,7 +33,7 @@ struct B {
 };
 #endif
 
-int main()
+int main(int, char**)
 {
   {
     A a;
@@ -49,4 +49,6 @@ int main()
     b.it2 = b.d.cbefore_begin();
   }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/max_size.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/max_size.pass.cpp
index 6b93a3db60b0e058b7488d7a4e2d54136c0c9c96..08d21d641163f4084b15330e2edae544a32f9ed1 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/max_size.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/max_size.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_allocator.h"
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
       typedef limited_allocator<int, 10> A;
@@ -44,4 +44,6 @@ int main()
       assert(c.max_size() <= max_dist);
       assert(c.max_size() <= alloc_max_size(c.get_allocator()));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/types.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/types.pass.cpp
index ff6c10e46308dcc2546ec98ef2da54b0f32bb139..01a7db039d46ff6cc13a96feb1d61abc90df8d90 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/types.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/types.pass.cpp
@@ -31,7 +31,7 @@
 
 struct A { std::forward_list<A> v; }; // incomplete type support
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::forward_list<char> C;
@@ -72,4 +72,6 @@ int main()
         typename std::iterator_traits<typename C::const_iterator>::difference_type>::value), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/allocator_mismatch.fail.cpp b/libcxx/test/std/containers/sequences/list/allocator_mismatch.fail.cpp
index 002954b4480f4d8b2188b954a235ef995560c590..39dcde477c291036a441555243752e07fbf52076 100644
--- a/libcxx/test/std/containers/sequences/list/allocator_mismatch.fail.cpp
+++ b/libcxx/test/std/containers/sequences/list/allocator_mismatch.fail.cpp
@@ -11,7 +11,9 @@
 
 #include <list>
 
-int main()
+int main(int, char**)
 {
     std::list<int, std::allocator<long> > l;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/incomplete_type.pass.cpp b/libcxx/test/std/containers/sequences/list/incomplete_type.pass.cpp
index 04b04d0bc2f7d2976c2dc63e094d1ac281a7bcfc..e68f06176b7b54d323938c438e051dbf66a9464a 100644
--- a/libcxx/test/std/containers/sequences/list/incomplete_type.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/incomplete_type.pass.cpp
@@ -21,6 +21,8 @@ struct A {
     std::list<A>::const_reverse_iterator crit;
 };
 
-int main() {
+int main(int, char**) {
     A a;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/iterators.pass.cpp b/libcxx/test/std/containers/sequences/list/iterators.pass.cpp
index 89cc3932d56f263af6b6eaeaa762ab041e62e428..0fe92dfba694f1e286af6ace6c659adb46f04e85 100644
--- a/libcxx/test/std/containers/sequences/list/iterators.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/iterators.pass.cpp
@@ -28,7 +28,7 @@ struct A
     int second;
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -152,4 +152,6 @@ int main()
     }
 #endif
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.capacity/empty.fail.cpp b/libcxx/test/std/containers/sequences/list/list.capacity/empty.fail.cpp
index 99325fcb67a9bb1fb4a31ac4648e3b9b871919d8..0cbaa464d4a1d4d5409efc0999dda2c0e95922d1 100644
--- a/libcxx/test/std/containers/sequences/list/list.capacity/empty.fail.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.capacity/empty.fail.cpp
@@ -20,8 +20,10 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     std::list<int> c;
     c.empty();  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.capacity/empty.pass.cpp b/libcxx/test/std/containers/sequences/list/list.capacity/empty.pass.cpp
index 27bd73e88459d0290658e733a83408e80e0da179..7619ec50853ad93c01dec4457bddae30592453af 100644
--- a/libcxx/test/std/containers/sequences/list/list.capacity/empty.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.capacity/empty.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::list<int> C;
@@ -42,4 +42,6 @@ int main()
     assert(c.empty());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.capacity/max_size.pass.cpp b/libcxx/test/std/containers/sequences/list/list.capacity/max_size.pass.cpp
index e3da37d73979823a4554fd2eff5c1c5dd5364fbf..8560a6a87f05ff92c80e4ea3c80d968a297ce96b 100644
--- a/libcxx/test/std/containers/sequences/list/list.capacity/max_size.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.capacity/max_size.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_allocator.h"
 #include "test_macros.h"
 
-int main() {
+int main(int, char**) {
   {
     typedef limited_allocator<int, 10> A;
     typedef std::list<int, A> C;
@@ -43,4 +43,6 @@ int main() {
     assert(c.max_size() <= max_dist);
     assert(c.max_size() <= alloc_max_size(c.get_allocator()));
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.capacity/resize_size.pass.cpp b/libcxx/test/std/containers/sequences/list/list.capacity/resize_size.pass.cpp
index 04476900dd0e23af1de0eec6e9f1cb78cee93de6..3c9e240d7523b3abc918a9dda1801e4d227bb82b 100644
--- a/libcxx/test/std/containers/sequences/list/list.capacity/resize_size.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.capacity/resize_size.pass.cpp
@@ -15,7 +15,7 @@
 #include "DefaultOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::list<int> l(5, 2);
@@ -77,4 +77,6 @@ int main()
     }
 #endif  // __LIBCPP_MOVE
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.capacity/resize_size_value.pass.cpp b/libcxx/test/std/containers/sequences/list/list.capacity/resize_size_value.pass.cpp
index 404bb0c1b65cfb64da4627a949bf7070da77cf55..db1c1419cca90cb2395e57a64e3971c6325a5e82 100644
--- a/libcxx/test/std/containers/sequences/list/list.capacity/resize_size_value.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.capacity/resize_size_value.pass.cpp
@@ -15,7 +15,7 @@
 #include "DefaultOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::list<double> l(5, 2);
@@ -49,4 +49,6 @@ int main()
         assert(l.back() == 3.5);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.capacity/size.pass.cpp b/libcxx/test/std/containers/sequences/list/list.capacity/size.pass.cpp
index b28b6572f9e050868ba7f5182163af888b1cbcf5..d4801e76c225556eb670f14352afe9e917011526 100644
--- a/libcxx/test/std/containers/sequences/list/list.capacity/size.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.capacity/size.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::list<int> C;
@@ -58,4 +58,6 @@ int main()
     assert(c.size() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.cons/assign_copy.pass.cpp b/libcxx/test/std/containers/sequences/list/list.cons/assign_copy.pass.cpp
index c4493cac7875a56f44c59f3e316c5d41d75c16a1..91ac1cfa6aa4f7872422b45405053e9515e45359 100644
--- a/libcxx/test/std/containers/sequences/list/list.cons/assign_copy.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.cons/assign_copy.pass.cpp
@@ -15,7 +15,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::list<int, test_allocator<int> > l(3, 2, test_allocator<int>(5));
@@ -40,4 +40,6 @@ int main()
         assert(l2.get_allocator() == min_allocator<int>());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.cons/assign_initializer_list.pass.cpp b/libcxx/test/std/containers/sequences/list/list.cons/assign_initializer_list.pass.cpp
index 80d5ad074a90451ca08b9b1c4f72f0082649862b..54c91ae4a12cc298a215be86951948c348e773c0 100644
--- a/libcxx/test/std/containers/sequences/list/list.cons/assign_initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.cons/assign_initializer_list.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::list<int> d;
@@ -39,4 +39,6 @@ int main()
     assert(*i++ == 5);
     assert(*i++ == 6);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.cons/assign_move.pass.cpp b/libcxx/test/std/containers/sequences/list/list.cons/assign_move.pass.cpp
index 7400ba5ca3f4b30e1351e0a3d4e29a50b35aa68e..1e826ed9115031b061249262f8f3828e5f4d9e65 100644
--- a/libcxx/test/std/containers/sequences/list/list.cons/assign_move.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.cons/assign_move.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::list<MoveOnly, test_allocator<MoveOnly> > l(test_allocator<MoveOnly>(5));
@@ -76,4 +76,6 @@ int main()
         assert(l.empty());
         assert(l2.get_allocator() == lo.get_allocator());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.cons/copy.pass.cpp b/libcxx/test/std/containers/sequences/list/list.cons/copy.pass.cpp
index 68b2e9d16f413a7cb8f1946aa44409b8cca620a3..153cd2dbc96b605d33c83117ee397995ec519ec1 100644
--- a/libcxx/test/std/containers/sequences/list/list.cons/copy.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.cons/copy.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::list<int> l(3, 2);
@@ -50,4 +50,6 @@ int main()
         assert(l2.get_allocator() == l.get_allocator());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.cons/copy_alloc.pass.cpp b/libcxx/test/std/containers/sequences/list/list.cons/copy_alloc.pass.cpp
index b722c40e602ab625090aec57060ab406b6aadf1b..14e95850225605468f4804269c9bd63ce356f0de 100644
--- a/libcxx/test/std/containers/sequences/list/list.cons/copy_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.cons/copy_alloc.pass.cpp
@@ -16,7 +16,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::list<int, test_allocator<int> > l(3, 2, test_allocator<int>(5));
@@ -38,4 +38,6 @@ int main()
         assert(l2.get_allocator() == min_allocator<int>());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.cons/deduct.fail.cpp b/libcxx/test/std/containers/sequences/list/list.cons/deduct.fail.cpp
index 6d9833b5f87b839fd136c950e1ba4933a3ebab4d..36982263dfced9102314af165caa4c5827b1bfad 100644
--- a/libcxx/test/std/containers/sequences/list/list.cons/deduct.fail.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.cons/deduct.fail.cpp
@@ -25,7 +25,7 @@
 
 struct A {};
 
-int main()
+int main(int, char**)
 {
 //  Test the explicit deduction guides
 
@@ -38,4 +38,6 @@ int main()
 //      deque<allocator<int>, allocator<allocator<int>>>
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.cons/deduct.pass.cpp b/libcxx/test/std/containers/sequences/list/list.cons/deduct.pass.cpp
index 20c017500e00dc878c258e773fb47a9a05d85870..03d3f38187e48e60b8f60b49c29e6f71270f5c25 100644
--- a/libcxx/test/std/containers/sequences/list/list.cons/deduct.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.cons/deduct.pass.cpp
@@ -29,7 +29,7 @@
 
 struct A {};
 
-int main()
+int main(int, char**)
 {
 
 //  Test the explicit deduction guides
@@ -99,4 +99,6 @@ int main()
     static_assert(std::is_same_v<decltype(lst)::allocator_type, std::allocator<long double>>, "");
     assert(lst.size() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.cons/default.pass.cpp b/libcxx/test/std/containers/sequences/list/list.cons/default.pass.cpp
index ffbfa0b21dc1fd3f88bb2f1d4f8d63b369f64f21..348390c4586078ba6dd5a8ec4768ace1aec7de20 100644
--- a/libcxx/test/std/containers/sequences/list/list.cons/default.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.cons/default.pass.cpp
@@ -15,7 +15,7 @@
 #include "DefaultOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::list<int> l;
@@ -64,4 +64,6 @@ int main()
         assert(std::distance(l.begin(), l.end()) == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.cons/default_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/list/list.cons/default_noexcept.pass.cpp
index b41f7320d0fbd1b6d90b9bad8cfb0c5b574373f9..93951e963618c6d7af362605facd93ca9dd85f4d 100644
--- a/libcxx/test/std/containers/sequences/list/list.cons/default_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.cons/default_noexcept.pass.cpp
@@ -29,7 +29,7 @@ struct some_alloc
     some_alloc(const some_alloc&);
 };
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -49,4 +49,6 @@ int main()
         typedef std::list<MoveOnly, some_alloc<MoveOnly>> C;
         static_assert(!std::is_nothrow_default_constructible<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.cons/default_stack_alloc.pass.cpp b/libcxx/test/std/containers/sequences/list/list.cons/default_stack_alloc.pass.cpp
index 1596a4e44b2e8085828a4d904a6aea9e1cd8b7d6..2e0b5203b8e976fc8f86fbe96bf3955ab2dd0da0 100644
--- a/libcxx/test/std/containers/sequences/list/list.cons/default_stack_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.cons/default_stack_alloc.pass.cpp
@@ -15,7 +15,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::list<int> l;
@@ -44,4 +44,6 @@ int main()
         assert(std::distance(l.begin(), l.end()) == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.cons/dtor_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/list/list.cons/dtor_noexcept.pass.cpp
index 64894dc38ddf228378a02ff195a468dcc5a993e8..62af49e639aa0e348c17708b1edd364ee24afd5b 100644
--- a/libcxx/test/std/containers/sequences/list/list.cons/dtor_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.cons/dtor_noexcept.pass.cpp
@@ -27,7 +27,7 @@ struct some_alloc
     ~some_alloc() noexcept(false);
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::list<MoveOnly> C;
@@ -47,4 +47,6 @@ int main()
         static_assert(!std::is_nothrow_destructible<C>::value, "");
     }
 #endif // _LIBCPP_VERSION
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.cons/initializer_list.pass.cpp b/libcxx/test/std/containers/sequences/list/list.cons/initializer_list.pass.cpp
index 61a277395e5ca9c6b32f291fa6a91c3f46357a0d..bd4ffeb137134504eded78de72ee9cab4db897c9 100644
--- a/libcxx/test/std/containers/sequences/list/list.cons/initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.cons/initializer_list.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::list<int> d = {3, 4, 5, 6};
@@ -37,4 +37,6 @@ int main()
     assert(*i++ == 5);
     assert(*i++ == 6);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.cons/initializer_list_alloc.pass.cpp b/libcxx/test/std/containers/sequences/list/list.cons/initializer_list_alloc.pass.cpp
index ec560ef8d34c7fd2c7c50681b48ed90b91169689..f6eca2112e1d5abb82e5fa16ae4fb1a5d123abc9 100644
--- a/libcxx/test/std/containers/sequences/list/list.cons/initializer_list_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.cons/initializer_list_alloc.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::list<int, test_allocator<int>> d({3, 4, 5, 6}, test_allocator<int>(3));
@@ -40,4 +40,6 @@ int main()
     assert(*i++ == 5);
     assert(*i++ == 6);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.cons/input_iterator.pass.cpp b/libcxx/test/std/containers/sequences/list/list.cons/input_iterator.pass.cpp
index ef6e11b25f130be34dbce9f5751a90839ce49d84..f7491f4501f78ee359022be5ca0de1342f34e73c 100644
--- a/libcxx/test/std/containers/sequences/list/list.cons/input_iterator.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.cons/input_iterator.pass.cpp
@@ -244,10 +244,12 @@ void test_ctor_under_alloc_with_alloc() {
 
 
 
-int main() {
+int main(int, char**) {
   basic_test();
   test_emplacable_concept();
   test_emplacable_concept_with_alloc();
   test_ctor_under_alloc();
   test_ctor_under_alloc_with_alloc();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.cons/move.pass.cpp b/libcxx/test/std/containers/sequences/list/list.cons/move.pass.cpp
index 9ad55ecdb012ba8e595464ab3119bcb44fc99f64..a79a3723231cfcac1483cea3b160c939538c943a 100644
--- a/libcxx/test/std/containers/sequences/list/list.cons/move.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.cons/move.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::list<MoveOnly, test_allocator<MoveOnly> > l(test_allocator<MoveOnly>(5));
@@ -59,4 +59,6 @@ int main()
         assert(l.empty());
         assert(l2.get_allocator() == lo.get_allocator());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.cons/move_alloc.pass.cpp b/libcxx/test/std/containers/sequences/list/list.cons/move_alloc.pass.cpp
index 80ef7cdde0aa44d4d4cb5e8879c2855d6759cb0b..d18ea2c4a0f4f1c7d4e65d4851efcc9d7f054e15 100644
--- a/libcxx/test/std/containers/sequences/list/list.cons/move_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.cons/move_alloc.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::list<MoveOnly, test_allocator<MoveOnly> > l(test_allocator<MoveOnly>(5));
@@ -72,4 +72,6 @@ int main()
         assert(l.empty());
         assert(l2.get_allocator() == min_allocator<MoveOnly>());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.cons/move_assign_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/list/list.cons/move_assign_noexcept.pass.cpp
index b12e3d9e3b71ebc36ffbeb59e16bcf39e3166b1b..c6c714595b4eb82ef9a144d038c9b482a6b844f6 100644
--- a/libcxx/test/std/containers/sequences/list/list.cons/move_assign_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.cons/move_assign_noexcept.pass.cpp
@@ -31,7 +31,7 @@ struct some_alloc
     some_alloc(const some_alloc&);
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::list<MoveOnly> C;
@@ -51,4 +51,6 @@ int main()
         static_assert(!std::is_nothrow_move_assignable<C>::value, "");
     }
 #endif // _LIBCPP_VERSION
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.cons/move_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/list/list.cons/move_noexcept.pass.cpp
index 1b40bbdff25e11e7597b027394988d613d039674..43abd019ad4d3564ca5cb1d58c0c5e74463cb28f 100644
--- a/libcxx/test/std/containers/sequences/list/list.cons/move_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.cons/move_noexcept.pass.cpp
@@ -29,7 +29,7 @@ struct some_alloc
     some_alloc(const some_alloc&);
 };
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -49,4 +49,6 @@ int main()
         typedef std::list<MoveOnly, some_alloc<MoveOnly>> C;
         static_assert(!std::is_nothrow_move_constructible<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.cons/op_equal_initializer_list.pass.cpp b/libcxx/test/std/containers/sequences/list/list.cons/op_equal_initializer_list.pass.cpp
index b0d6a374e1c9bc88a15dffa76fcd507912301782..58ea88f4315060158824ef1652062af4f8318e83 100644
--- a/libcxx/test/std/containers/sequences/list/list.cons/op_equal_initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.cons/op_equal_initializer_list.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::list<int> d;
@@ -38,4 +38,6 @@ int main()
     assert(*i++ == 5);
     assert(*i++ == 6);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.cons/size_type.pass.cpp b/libcxx/test/std/containers/sequences/list/list.cons/size_type.pass.cpp
index f11d617e134f96e5465724fba747f0f3d4ddce18..ef365d09fd435e6c4dcc7559bc639df505529b10 100644
--- a/libcxx/test/std/containers/sequences/list/list.cons/size_type.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.cons/size_type.pass.cpp
@@ -37,7 +37,7 @@ test3(unsigned n, Allocator const &alloc = Allocator())
 }
 
 
-int main()
+int main(int, char**)
 {
     {
         std::list<int> l(3);
@@ -100,4 +100,6 @@ int main()
         assert(std::distance(l.begin(), l.end()) == 3);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.cons/size_value_alloc.pass.cpp b/libcxx/test/std/containers/sequences/list/list.cons/size_value_alloc.pass.cpp
index 25b3425abe3ca2566aed0586443c62c6f1744953..282de37bbc536989d28ca31efd884bc9a1baf6b5 100644
--- a/libcxx/test/std/containers/sequences/list/list.cons/size_value_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.cons/size_value_alloc.pass.cpp
@@ -16,7 +16,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::list<int> l(3, 2);
@@ -76,4 +76,6 @@ int main()
         assert(*i == 2);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.erasure/erase.pass.cpp b/libcxx/test/std/containers/sequences/list/list.erasure/erase.pass.cpp
index 6f0b5fc89254189232af3cfeef7dc526f32d220b..9c03c7282487044b9acb3532b72caed6405b86c3 100644
--- a/libcxx/test/std/containers/sequences/list/list.erasure/erase.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.erasure/erase.pass.cpp
@@ -66,7 +66,7 @@ void test()
     test0(S({1,2,1}), opt(3), S({1,2,1}));
 }
 
-int main()
+int main(int, char**)
 {
     test<std::list<int>>();
     test<std::list<int, min_allocator<int>>> ();
@@ -74,4 +74,6 @@ int main()
 
     test<std::list<long>>();
     test<std::list<double>>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.erasure/erase_if.pass.cpp b/libcxx/test/std/containers/sequences/list/list.erasure/erase_if.pass.cpp
index 152f666331541af89d930f986ce3a826f1c94b62..f25d3e830f2e8b1d7456e0cb76c4635ce7da2513 100644
--- a/libcxx/test/std/containers/sequences/list/list.erasure/erase_if.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.erasure/erase_if.pass.cpp
@@ -66,7 +66,7 @@ void test()
     test0(S({1,2,3}), False, S({1,2,3}));
 }
 
-int main()
+int main(int, char**)
 {
     test<std::list<int>>();
     test<std::list<int, min_allocator<int>>> ();
@@ -74,4 +74,6 @@ int main()
 
     test<std::list<long>>();
     test<std::list<double>>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.modifiers/clear.pass.cpp b/libcxx/test/std/containers/sequences/list/list.modifiers/clear.pass.cpp
index ba9e413e52af7518ae7cfcc56eb684d94ea75b9d..0afd0a5483512cb4588a9a47329a01f1c57f1936 100644
--- a/libcxx/test/std/containers/sequences/list/list.modifiers/clear.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.modifiers/clear.pass.cpp
@@ -16,7 +16,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     int a[] = {1, 2, 3};
@@ -34,4 +34,6 @@ int main()
     assert(c.empty());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.modifiers/emplace.pass.cpp b/libcxx/test/std/containers/sequences/list/list.modifiers/emplace.pass.cpp
index 5183cd9a7f2a96efffcf4de72d7ddb8595bcb8a2..642e8434221c4e3536feb0922ecfd775b221408f 100644
--- a/libcxx/test/std/containers/sequences/list/list.modifiers/emplace.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.modifiers/emplace.pass.cpp
@@ -34,7 +34,7 @@ public:
     double getd() const {return d_;}
 };
 
-int main()
+int main(int, char**)
 {
     {
     std::list<A> c;
@@ -63,4 +63,6 @@ int main()
     assert(c.back().getd() == 4.5);
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.modifiers/emplace_back.pass.cpp b/libcxx/test/std/containers/sequences/list/list.modifiers/emplace_back.pass.cpp
index ca428ec65064d81d39b61b6ebc89e8ae37c0ccd2..b7eaa7047bd8e22f525c3d0e86f5dc79e47a123f 100644
--- a/libcxx/test/std/containers/sequences/list/list.modifiers/emplace_back.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.modifiers/emplace_back.pass.cpp
@@ -34,7 +34,7 @@ public:
     double getd() const {return d_;}
 };
 
-int main()
+int main(int, char**)
 {
     {
     std::list<A> c;
@@ -84,4 +84,6 @@ int main()
     assert(c.back().geti() == 3);
     assert(c.back().getd() == 4.5);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.modifiers/emplace_front.pass.cpp b/libcxx/test/std/containers/sequences/list/list.modifiers/emplace_front.pass.cpp
index 25d7eb37d3be9920238578a6e8f10628e2622186..eece4186caa1004dfe00c17f0a0b2b292eccb6d2 100644
--- a/libcxx/test/std/containers/sequences/list/list.modifiers/emplace_front.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.modifiers/emplace_front.pass.cpp
@@ -33,7 +33,7 @@ public:
     double getd() const {return d_;}
 };
 
-int main()
+int main(int, char**)
 {
     {
     std::list<A> c;
@@ -84,4 +84,6 @@ int main()
     assert(c.back().geti() == 2);
     assert(c.back().getd() == 3.5);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.modifiers/erase_iter.pass.cpp b/libcxx/test/std/containers/sequences/list/list.modifiers/erase_iter.pass.cpp
index 824c3680644eb4fa55202b987b53ac9fa48383cf..87486b61690dd3baad5e43c9c4837ab2f7b68f00 100644
--- a/libcxx/test/std/containers/sequences/list/list.modifiers/erase_iter.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.modifiers/erase_iter.pass.cpp
@@ -15,7 +15,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     int a1[] = {1, 2, 3};
@@ -61,4 +61,6 @@ int main()
     assert(distance(l1.begin(), l1.end()) == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.modifiers/erase_iter_iter.pass.cpp b/libcxx/test/std/containers/sequences/list/list.modifiers/erase_iter_iter.pass.cpp
index 8166efbd34351d6b55743c05b258140c4888b1c3..1df39913c53ca596945f6d7b34fd17c8a9924fa1 100644
--- a/libcxx/test/std/containers/sequences/list/list.modifiers/erase_iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.modifiers/erase_iter_iter.pass.cpp
@@ -15,7 +15,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     int a1[] = {1, 2, 3};
     {
@@ -80,4 +80,6 @@ int main()
         assert(i == l1.begin());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.modifiers/insert_iter_initializer_list.pass.cpp b/libcxx/test/std/containers/sequences/list/list.modifiers/insert_iter_initializer_list.pass.cpp
index 5cfde77e29b3eefc3e18835b79b97170bbbd2d0b..98dcd0ba28df79f219360b93a30f45807fa7dd51 100644
--- a/libcxx/test/std/containers/sequences/list/list.modifiers/insert_iter_initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.modifiers/insert_iter_initializer_list.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::list<int> d(10, 1);
@@ -61,4 +61,6 @@ int main()
     assert(*i++ == 1);
     assert(*i++ == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.modifiers/insert_iter_iter_iter.pass.cpp b/libcxx/test/std/containers/sequences/list/list.modifiers/insert_iter_iter_iter.pass.cpp
index 0070266498ffcf533aedfde4f591949f2d872989..22ef0f72b909007be6fc80e9b7c390bcc9a60c86 100644
--- a/libcxx/test/std/containers/sequences/list/list.modifiers/insert_iter_iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.modifiers/insert_iter_iter_iter.pass.cpp
@@ -81,10 +81,12 @@ void test() {
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test<std::list<int> >();
 #if TEST_STD_VER >= 11
     test<std::list<int, min_allocator<int>>>();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.modifiers/insert_iter_rvalue.pass.cpp b/libcxx/test/std/containers/sequences/list/list.modifiers/insert_iter_rvalue.pass.cpp
index eefee91238300466a322ed5dad671393e795393b..4ded48991a5bf99b086a9d0ab3ca73b04be695a4 100644
--- a/libcxx/test/std/containers/sequences/list/list.modifiers/insert_iter_rvalue.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.modifiers/insert_iter_rvalue.pass.cpp
@@ -18,7 +18,7 @@
 #include "MoveOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::list<MoveOnly> l1;
@@ -40,4 +40,6 @@ int main()
     assert(l1.front() == MoveOnly(2));
     assert(l1.back() == MoveOnly(1));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.modifiers/insert_iter_size_value.pass.cpp b/libcxx/test/std/containers/sequences/list/list.modifiers/insert_iter_size_value.pass.cpp
index 2fc8ab7c4f5ae7ec46fc9a94f10e997304838c0a..f577fc0bcb4b505b83a2950272fa0656f4dd2075 100644
--- a/libcxx/test/std/containers/sequences/list/list.modifiers/insert_iter_size_value.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.modifiers/insert_iter_size_value.pass.cpp
@@ -44,10 +44,12 @@ void test() {
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test<std::list<int> >();
 #if TEST_STD_VER >= 11
     test<std::list<int, min_allocator<int>>>();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.modifiers/insert_iter_value.pass.cpp b/libcxx/test/std/containers/sequences/list/list.modifiers/insert_iter_value.pass.cpp
index 614f57d1263b5c563fdd84c37629ce014cedb430..10a3d9704063c883bce888a7ebf12cff5324474b 100644
--- a/libcxx/test/std/containers/sequences/list/list.modifiers/insert_iter_value.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.modifiers/insert_iter_value.pass.cpp
@@ -46,10 +46,12 @@ void test()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test<std::list<int> >();
 #if TEST_STD_VER >= 11
     test<std::list<int, min_allocator<int>>>();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.modifiers/pop_back.pass.cpp b/libcxx/test/std/containers/sequences/list/list.modifiers/pop_back.pass.cpp
index 7247e828dda18ab65d428fab570ce50ecda59d8b..c4c88d421d6089eae8dab9f6ff1087b889719596 100644
--- a/libcxx/test/std/containers/sequences/list/list.modifiers/pop_back.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.modifiers/pop_back.pass.cpp
@@ -16,7 +16,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     int a[] = {1, 2, 3};
@@ -40,4 +40,6 @@ int main()
     assert(c.empty());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.modifiers/pop_front.pass.cpp b/libcxx/test/std/containers/sequences/list/list.modifiers/pop_front.pass.cpp
index 9a0104d030ab0e20549e5c2b1317c938cb8be7e4..3decb94c4214fb88454deecaf80896ce57f454b9 100644
--- a/libcxx/test/std/containers/sequences/list/list.modifiers/pop_front.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.modifiers/pop_front.pass.cpp
@@ -15,7 +15,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     int a[] = {1, 2, 3};
@@ -39,4 +39,6 @@ int main()
     assert(c.empty());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.modifiers/push_back.pass.cpp b/libcxx/test/std/containers/sequences/list/list.modifiers/push_back.pass.cpp
index dba7c0f681e55ef8dd7f4321cd179f7d7150be9b..e4aa404416f5665aeca721850860c834cd09d1ef 100644
--- a/libcxx/test/std/containers/sequences/list/list.modifiers/push_back.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.modifiers/push_back.pass.cpp
@@ -15,7 +15,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::list<int> c;
@@ -33,4 +33,6 @@ int main()
     assert((c == std::list<int, min_allocator<int>>(a, a+5)));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.modifiers/push_back_exception_safety.pass.cpp b/libcxx/test/std/containers/sequences/list/list.modifiers/push_back_exception_safety.pass.cpp
index f2b7664a15d3bd30d178a9ba0f72055159ad1422..a6bbc256e0beb229fe2b7a29bcd95c550226111d 100644
--- a/libcxx/test/std/containers/sequences/list/list.modifiers/push_back_exception_safety.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.modifiers/push_back_exception_safety.pass.cpp
@@ -57,7 +57,7 @@ CMyClass::~CMyClass() {
     assert(fMagicValue == kFinishedConstructionMagicValue);
 }
 
-int main()
+int main(int, char**)
 {
     CMyClass instance;
     std::list<CMyClass> vec;
@@ -70,4 +70,6 @@ int main()
     }
     catch (...) {
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.modifiers/push_back_rvalue.pass.cpp b/libcxx/test/std/containers/sequences/list/list.modifiers/push_back_rvalue.pass.cpp
index 0a4c4014b3871d12c72ac18f2a2211c20cc7a72c..5894c2cc889d0c77aba699eaed5b9f4ef636d827 100644
--- a/libcxx/test/std/containers/sequences/list/list.modifiers/push_back_rvalue.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.modifiers/push_back_rvalue.pass.cpp
@@ -18,7 +18,7 @@
 #include "MoveOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::list<MoveOnly> l1;
@@ -40,4 +40,6 @@ int main()
     assert(l1.front() == MoveOnly(1));
     assert(l1.back() == MoveOnly(2));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.modifiers/push_front.pass.cpp b/libcxx/test/std/containers/sequences/list/list.modifiers/push_front.pass.cpp
index 980b2515eb07a98c7fcbee393af1729a870a9dbe..27e39e90a7bc3e9c3fa373a717bec29a63e4dfba 100644
--- a/libcxx/test/std/containers/sequences/list/list.modifiers/push_front.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.modifiers/push_front.pass.cpp
@@ -15,7 +15,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::list<int> c;
@@ -33,4 +33,6 @@ int main()
     assert((c == std::list<int, min_allocator<int>>(a, a+5)));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.modifiers/push_front_exception_safety.pass.cpp b/libcxx/test/std/containers/sequences/list/list.modifiers/push_front_exception_safety.pass.cpp
index 7b680396101393df758ea6a7a776d0c639bf6d3b..49f86222aeed457f6cd324d02936f2f07594c6d9 100644
--- a/libcxx/test/std/containers/sequences/list/list.modifiers/push_front_exception_safety.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.modifiers/push_front_exception_safety.pass.cpp
@@ -57,7 +57,7 @@ CMyClass::~CMyClass() {
     assert(fMagicValue == kFinishedConstructionMagicValue);
 }
 
-int main()
+int main(int, char**)
 {
     CMyClass instance;
     std::list<CMyClass> vec;
@@ -70,4 +70,6 @@ int main()
     }
     catch (...) {
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.modifiers/push_front_rvalue.pass.cpp b/libcxx/test/std/containers/sequences/list/list.modifiers/push_front_rvalue.pass.cpp
index 5f74b15975ffb75c2d7c9d0fa322903ff76911d2..0020112858f03ad71dbbee6aee030001e8e1395d 100644
--- a/libcxx/test/std/containers/sequences/list/list.modifiers/push_front_rvalue.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.modifiers/push_front_rvalue.pass.cpp
@@ -18,7 +18,7 @@
 #include "MoveOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::list<MoveOnly> l1;
@@ -40,4 +40,6 @@ int main()
     assert(l1.front() == MoveOnly(2));
     assert(l1.back() == MoveOnly(1));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.ops/merge.pass.cpp b/libcxx/test/std/containers/sequences/list/list.ops/merge.pass.cpp
index eb60a416547c9ad038ccfa5f589c228453350f3b..c2a552cf62c1096cb62c8fa800ecabc3e0ad6b0c 100644
--- a/libcxx/test/std/containers/sequences/list/list.ops/merge.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.ops/merge.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     int a1[] = {1, 3, 7, 9, 10};
@@ -48,4 +48,6 @@ int main()
     assert(c2.empty());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.ops/merge_comp.pass.cpp b/libcxx/test/std/containers/sequences/list/list.ops/merge_comp.pass.cpp
index d2d048b38310d10c82ae99d3a61d2922b5c4d748..911c3d09af18f4d53ee8d7e864fc5acb245ce8d3 100644
--- a/libcxx/test/std/containers/sequences/list/list.ops/merge_comp.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.ops/merge_comp.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     int a1[] = {10, 9, 7, 3, 1};
@@ -48,4 +48,6 @@ int main()
     assert(c2.empty());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.ops/remove.pass.cpp b/libcxx/test/std/containers/sequences/list/list.ops/remove.pass.cpp
index db6fd89a8d941c80f819b9133c0517026a448c56..dab23f0414fa9fa8390afe66af8ad2b6f6f2e0f0 100644
--- a/libcxx/test/std/containers/sequences/list/list.ops/remove.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.ops/remove.pass.cpp
@@ -32,7 +32,7 @@ struct S {
   int *i_;
 };
 
-int main() {
+int main(int, char**) {
   {
     int a1[] = {1, 2, 3, 4};
     int a2[] = {1, 2, 4};
@@ -79,4 +79,6 @@ int main() {
     assert((c == std::list<int, min_allocator<int>>(a2, a2 + 3)));
   }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.ops/remove_if.pass.cpp b/libcxx/test/std/containers/sequences/list/list.ops/remove_if.pass.cpp
index 29dfafaaa73ea0bd3c8a3c24810199878322688f..f903278b3f1b4081639535f7a0759c3a0f7707c3 100644
--- a/libcxx/test/std/containers/sequences/list/list.ops/remove_if.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.ops/remove_if.pass.cpp
@@ -29,7 +29,7 @@ bool g(int i)
 
 typedef unary_counting_predicate<bool(*)(int), int> Predicate;
 
-int main()
+int main(int, char**)
 {
     {
     int a1[] = {1, 2, 3, 4};
@@ -60,4 +60,6 @@ int main()
     assert(cp.count() == 4);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.ops/reverse.pass.cpp b/libcxx/test/std/containers/sequences/list/list.ops/reverse.pass.cpp
index a8e5f50a21a4ffc45f0f91b0b9a93c95365a6752..0cf1242df5913335cd82fd41cc470a44e6466a43 100644
--- a/libcxx/test/std/containers/sequences/list/list.ops/reverse.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.ops/reverse.pass.cpp
@@ -15,7 +15,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     int a1[] = {11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0};
@@ -33,4 +33,6 @@ int main()
     assert((c1 == std::list<int, min_allocator<int>>(a2, a2+sizeof(a2)/sizeof(a2[0]))));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.ops/sort.pass.cpp b/libcxx/test/std/containers/sequences/list/list.ops/sort.pass.cpp
index 9cc92ef0d19538d741eda7cefbbff3434fa19233..cd229c2d214f8d1e1bdd4bb0a84436eb9ae93679 100644
--- a/libcxx/test/std/containers/sequences/list/list.ops/sort.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.ops/sort.pass.cpp
@@ -15,7 +15,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     int a1[] = {4, 8, 1, 0, 5, 7, 2, 3, 6, 11, 10, 9};
@@ -33,4 +33,6 @@ int main()
     assert((c1 == std::list<int, min_allocator<int>>(a2, a2+sizeof(a2)/sizeof(a2[0]))));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.ops/sort_comp.pass.cpp b/libcxx/test/std/containers/sequences/list/list.ops/sort_comp.pass.cpp
index f7dc6b0b300a1d6d8a7c4ce2913b5b8e4dc4cef7..a87e32acccb62d58db7a0c831af6ec5780ee44ad 100644
--- a/libcxx/test/std/containers/sequences/list/list.ops/sort_comp.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.ops/sort_comp.pass.cpp
@@ -35,7 +35,7 @@ struct throwingLess {
 #endif
 
 
-int main()
+int main(int, char**)
 {
     {
     int a1[] = {4, 8, 1, 0, 5, 7, 2, 3, 6, 11, 10, 9};
@@ -75,4 +75,6 @@ int main()
     assert((c1 == std::list<int, min_allocator<int>>(a2, a2+sizeof(a2)/sizeof(a2[0]))));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.ops/splice_pos_list.pass.cpp b/libcxx/test/std/containers/sequences/list/list.ops/splice_pos_list.pass.cpp
index e1d9f4c5218819c1e97bd73328290279fa656ec8..6a921e25ea9342208b366520ca98fc7fcb02132d 100644
--- a/libcxx/test/std/containers/sequences/list/list.ops/splice_pos_list.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.ops/splice_pos_list.pass.cpp
@@ -16,7 +16,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     int a1[] = {1, 2, 3};
     int a2[] = {4, 5, 6};
@@ -780,4 +780,6 @@ int main()
         assert(*i == 6);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.ops/splice_pos_list_iter.pass.cpp b/libcxx/test/std/containers/sequences/list/list.ops/splice_pos_list_iter.pass.cpp
index b87e6b8252aafc07b6be31c03dbb3a8e289005d7..9388b559fd6e0797a344f765f886f0fbe91f771e 100644
--- a/libcxx/test/std/containers/sequences/list/list.ops/splice_pos_list_iter.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.ops/splice_pos_list_iter.pass.cpp
@@ -16,7 +16,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     int a1[] = {1, 2, 3};
     int a2[] = {4, 5, 6};
@@ -334,4 +334,6 @@ int main()
         assert(*i == 2);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.ops/splice_pos_list_iter_iter.pass.cpp b/libcxx/test/std/containers/sequences/list/list.ops/splice_pos_list_iter_iter.pass.cpp
index e4c5752df608fb04904ab20dc200148cca6ac7c0..d22321b244029820b23ce897473f61d7a0bdff54 100644
--- a/libcxx/test/std/containers/sequences/list/list.ops/splice_pos_list_iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.ops/splice_pos_list_iter_iter.pass.cpp
@@ -16,7 +16,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     int a1[] = {1, 2, 3};
     int a2[] = {4, 5, 6};
@@ -214,4 +214,6 @@ int main()
         assert(*i == 4);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.ops/unique.pass.cpp b/libcxx/test/std/containers/sequences/list/list.ops/unique.pass.cpp
index e5e45949168ae496103212dd06c8ff95db85490c..651ffbc7baee833a6f5f1d8ddf34ad5de53d8685 100644
--- a/libcxx/test/std/containers/sequences/list/list.ops/unique.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.ops/unique.pass.cpp
@@ -15,7 +15,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     int a1[] = {2, 1, 1, 4, 4, 4, 4, 3, 3};
@@ -33,4 +33,6 @@ int main()
     assert((c == std::list<int, min_allocator<int>>(a2, a2+4)));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.ops/unique_pred.pass.cpp b/libcxx/test/std/containers/sequences/list/list.ops/unique_pred.pass.cpp
index a3f149d05edf09702a14f2ca6fa1066ad4b4fafb..dd0bcd77b6f1984dbf13eaa8b881dd272a824f28 100644
--- a/libcxx/test/std/containers/sequences/list/list.ops/unique_pred.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.ops/unique_pred.pass.cpp
@@ -20,7 +20,7 @@ bool g(int x, int y)
     return x == y;
 }
 
-int main()
+int main(int, char**)
 {
     {
     int a1[] = {2, 1, 1, 4, 4, 4, 4, 3, 3};
@@ -38,4 +38,6 @@ int main()
     assert((c == std::list<int, min_allocator<int>>(a2, a2+4)));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.special/swap.pass.cpp b/libcxx/test/std/containers/sequences/list/list.special/swap.pass.cpp
index de98cfe9f2a26bfba091df44eedee8fbf8403536..be7df207bdd197dbfc0f54c910c2962570e0dbf4 100644
--- a/libcxx/test/std/containers/sequences/list/list.special/swap.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.special/swap.pass.cpp
@@ -16,7 +16,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         int a1[] = {1, 3, 7, 9, 10};
@@ -136,4 +136,6 @@ int main()
         assert(c2.get_allocator() == A());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.special/swap_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/list/list.special/swap_noexcept.pass.cpp
index c6e4f61ef2aeee2221fea794abe9e4b8c3248c29..86634dd838d09828ffb4ac4be0a719a9f7c6a482 100644
--- a/libcxx/test/std/containers/sequences/list/list.special/swap_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.special/swap_noexcept.pass.cpp
@@ -52,7 +52,7 @@ struct some_alloc2
     typedef std::true_type is_always_equal;
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::list<MoveOnly> C;
@@ -85,4 +85,6 @@ int main()
     }
 #endif
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/list/types.pass.cpp b/libcxx/test/std/containers/sequences/list/types.pass.cpp
index bf872fffd93b671ccf95f55386ff16296fe2b7ca..914f9abab7d07ce69aee03a210a98858988170b0 100644
--- a/libcxx/test/std/containers/sequences/list/types.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/types.pass.cpp
@@ -28,7 +28,7 @@
 
 struct A { std::list<A> v; }; // incomplete type support
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::list<int> C;
@@ -65,4 +65,6 @@ int main()
         typename std::iterator_traits<typename C::const_iterator>::difference_type>::value), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/nothing_to_do.pass.cpp b/libcxx/test/std/containers/sequences/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/containers/sequences/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/containers/sequences/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/assign_copy.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/assign_copy.pass.cpp
index cffc3bfff0f4adcda5f37e677067ed8724934256..5aa86839ff4f0875b7c8da380f09bbab7eaf4177 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/assign_copy.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/assign_copy.pass.cpp
@@ -15,7 +15,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<bool, test_allocator<bool> > l(3, true, test_allocator<bool>(5));
@@ -40,4 +40,6 @@ int main()
         assert(l2.get_allocator() == min_allocator<bool>());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/assign_initializer_list.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/assign_initializer_list.pass.cpp
index 36d32c73c735dc4463e97551f540f8a06d10d179..bbd980bd325529fdb33ab9bacc98ca4afd3819f9 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/assign_initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/assign_initializer_list.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::vector<bool> d;
@@ -37,4 +37,6 @@ int main()
     assert(d[2] == false);
     assert(d[3] == true);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/assign_move.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/assign_move.pass.cpp
index 59fb08fbf2368973514285f783651af0f881841a..b70e9cde65b44bf0f1824227cc9d12c9c29fcc35 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/assign_move.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/assign_move.pass.cpp
@@ -17,7 +17,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<bool, test_allocator<bool> > l(test_allocator<bool>(5));
@@ -75,4 +75,6 @@ int main()
         assert(l.empty());
         assert(l2.get_allocator() == lo.get_allocator());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/capacity.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/capacity.pass.cpp
index 14ebc6c1e63d31a80d6d5080ee37eb1099913133..e24ebe00c6a043609f0f8c67c42ba1d73902f5f5 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/capacity.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/capacity.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<bool> v;
@@ -40,4 +40,6 @@ int main()
         assert(v.capacity() >= 101);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/construct_default.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/construct_default.pass.cpp
index e481ece9f71c90c9ef1a6b768c67445f04e0e8f3..3fd2bf8d195de838fe2ff48cd0d22b1c12b055ac 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/construct_default.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/construct_default.pass.cpp
@@ -59,7 +59,7 @@ test1(const typename C::allocator_type& a)
     assert(c.get_allocator() == a);
 }
 
-int main()
+int main(int, char**)
 {
     {
     test0<std::vector<bool> >();
@@ -75,4 +75,6 @@ int main()
     test1<std::vector<bool, explicit_allocator<bool> > >(explicit_allocator<bool>());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/construct_iter_iter.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/construct_iter_iter.pass.cpp
index 44931a75c6a7638551736a8c4300760570035ae3..e20f300982c9185c87c032ca799cd65196147d63 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/construct_iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/construct_iter_iter.pass.cpp
@@ -30,7 +30,7 @@ test(Iterator first, Iterator last)
         assert(*i == *first);
 }
 
-int main()
+int main(int, char**)
 {
     bool a[] = {0, 1, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0};
     bool* an = a + sizeof(a)/sizeof(a[0]);
@@ -46,4 +46,6 @@ int main()
     test<std::vector<bool, min_allocator<bool>> >(random_access_iterator<const bool*>(a), random_access_iterator<const bool*>(an));
     test<std::vector<bool, min_allocator<bool>> >(a, an);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/construct_iter_iter_alloc.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/construct_iter_iter_alloc.pass.cpp
index 49d2c23e0ea3c795cbfd02f32fe3ba2be32e4441..2aa2b42648f20bad89c4a8470a3ef5c5d7002253 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/construct_iter_iter_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/construct_iter_iter_alloc.pass.cpp
@@ -31,7 +31,7 @@ test(Iterator first, Iterator last, const typename C::allocator_type& a)
         assert(*i == *first);
 }
 
-int main()
+int main(int, char**)
 {
     bool a[] = {0, 1, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0};
     bool* an = a + sizeof(a)/sizeof(a[0]);
@@ -53,4 +53,6 @@ int main()
     test<std::vector<bool, min_allocator<bool>> >(a, an, alloc);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/construct_size.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/construct_size.pass.cpp
index 8300924b6d0104187acbfbba733d3835b17acab9..2763df7e11d5c7710d6285f3ebc5a16662579be8 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/construct_size.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/construct_size.pass.cpp
@@ -56,11 +56,13 @@ test(typename C::size_type n)
     test2<C> ( n );
 }
 
-int main()
+int main(int, char**)
 {
     test<std::vector<bool> >(50);
 #if TEST_STD_VER >= 11
     test<std::vector<bool, min_allocator<bool>> >(50);
     test2<std::vector<bool, test_allocator<bool>> >( 100, test_allocator<bool>(23));
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/construct_size_value.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/construct_size_value.pass.cpp
index ecde426780992992dbc5650052b1fa6bb1b2857e..068989330a31f686e53ef38de96ba5c3e98b1581 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/construct_size_value.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/construct_size_value.pass.cpp
@@ -28,10 +28,12 @@ test(typename C::size_type n, const typename C::value_type& x)
         assert(*i == x);
 }
 
-int main()
+int main(int, char**)
 {
     test<std::vector<bool> >(50, true);
 #if TEST_STD_VER >= 11
     test<std::vector<bool, min_allocator<bool>> >(50, true);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/construct_size_value_alloc.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/construct_size_value_alloc.pass.cpp
index c9439246560e2020c677bc494240b8b6f1579f93..e19f3c4a9d531d57cb2b550e868ecd20c164c56c 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/construct_size_value_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/construct_size_value_alloc.pass.cpp
@@ -30,10 +30,12 @@ test(typename C::size_type n, const typename C::value_type& x,
         assert(*i == x);
 }
 
-int main()
+int main(int, char**)
 {
     test<std::vector<bool> >(50, true, std::allocator<bool>());
 #if TEST_STD_VER >= 11
     test<std::vector<bool, min_allocator<bool>> >(50, true, min_allocator<bool>());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/copy.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/copy.pass.cpp
index 66a15a4c86129d11b65e5f4b077567c7831c1c05..618a37faf70afda7fa5f1c7e1169d3cdaa0e5dbf 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/copy.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/copy.pass.cpp
@@ -29,7 +29,7 @@ test(const C& x)
     assert(c == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
         bool a[] = {0, 1, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0};
@@ -61,4 +61,6 @@ int main()
         assert(v2.get_allocator() == v.get_allocator());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/copy_alloc.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/copy_alloc.pass.cpp
index 9a63e5a555d328d2eae1ee856f5e735dc7635884..7970b2c7ed962891e4a66818a7917559a3d0a48d 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/copy_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/copy_alloc.pass.cpp
@@ -28,7 +28,7 @@ test(const C& x, const typename C::allocator_type& a)
     assert(c == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
         bool a[] = {0, 1, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0};
@@ -60,4 +60,6 @@ int main()
         assert(l2.get_allocator() == min_allocator<bool>());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/default_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/default_noexcept.pass.cpp
index bffeaf64c74d3062393755b7407fa323455057ca..800bd1b4b1c54f4cf3ea3ddea94a3bcfa79b8373 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/default_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/default_noexcept.pass.cpp
@@ -30,7 +30,7 @@ struct some_alloc
     some_alloc(const some_alloc&);
 };
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -50,4 +50,6 @@ int main()
         static_assert(!std::is_nothrow_default_constructible<C>::value, "");
     }
 #endif // _LIBCPP_VERSION
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/dtor_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/dtor_noexcept.pass.cpp
index 9d7858b4f8c65c5c5f4f7f7a463b26c6965317ab..949add271a28d869c7a34b8232773d4bfdc49fdc 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/dtor_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/dtor_noexcept.pass.cpp
@@ -26,7 +26,7 @@ struct some_alloc
     ~some_alloc() noexcept(false);
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::vector<bool> C;
@@ -46,4 +46,6 @@ int main()
         static_assert(!std::is_nothrow_destructible<C>::value, "");
     }
 #endif // _LIBCPP_VERSION
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/emplace.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/emplace.pass.cpp
index 26b9039073c9eebeafb2da0323487b09a560c33c..129cbff154ec32a8d1a401ff45ece1b04e22a5da 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/emplace.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/emplace.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::vector<bool> C;
@@ -63,4 +63,6 @@ int main()
         assert(c[1] == true);
         assert(c.back() == true);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/emplace_back.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/emplace_back.pass.cpp
index 0ad7210021448542fa1645dbdfff3df02b9a6b3c..974b7c24ac7faf6f9f6b708407de8d9fa8efc997 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/emplace_back.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/emplace_back.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::vector<bool> C;
@@ -87,4 +87,6 @@ int main()
         assert(c[1] == true);
         assert(c.back() == true);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/empty.fail.cpp b/libcxx/test/std/containers/sequences/vector.bool/empty.fail.cpp
index 0381d7eb24b92294b74debe30f8df30ff4958eea..0a84eb79d125d52e186855ebd7ead5499d9727f4 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/empty.fail.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/empty.fail.cpp
@@ -20,8 +20,10 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     std::vector<bool> c;
     c.empty();  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/empty.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/empty.pass.cpp
index e3226a12835826e0927dec080e27d975b3c6def7..e0c0243e139022fddc6317889dbf4357574c2723 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/empty.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/empty.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::vector<bool> C;
@@ -42,4 +42,6 @@ int main()
     assert(c.empty());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/enabled_hash.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/enabled_hash.pass.cpp
index ba8bdf5312a0736e7cbe93128f44b550f6262333..f6631cf2d49c3f24d842e7978ffe9f2095f9255e 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/enabled_hash.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/enabled_hash.pass.cpp
@@ -18,10 +18,12 @@
 #include "poisoned_hash_helper.hpp"
 #include "min_allocator.h"
 
-int main() {
+int main(int, char**) {
   test_library_hash_specializations_available();
   {
     test_hash_enabled_for_type<std::vector<bool> >();
     test_hash_enabled_for_type<std::vector<bool, min_allocator<bool>>>();
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/erase_iter.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/erase_iter.pass.cpp
index b0a65c9ae27e4ed6022a28b45c12ac9023013141..c3d6bfd5de01faaca9172281258244ac259935ea 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/erase_iter.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/erase_iter.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     bool a1[] = {1, 0, 1};
     {
@@ -61,4 +61,6 @@ int main()
     assert(distance(l1.begin(), l1.end()) == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/erase_iter_iter.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/erase_iter_iter.pass.cpp
index b574552309af742997156c75481666aca82b35ac..89763017e971473243ff8672e4c46f383ec0b482 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/erase_iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/erase_iter_iter.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     bool a1[] = {1, 0, 1};
     {
@@ -81,4 +81,6 @@ int main()
         assert(i == l1.begin());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/find.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/find.pass.cpp
index 265b519de78808cbc8d86b100c1ba4e05d08330a..883b5b4dbca58920c62ff5b2249de612654f7733 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/find.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/find.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         for (unsigned i = 1; i < 256; ++i)
@@ -38,4 +38,6 @@ int main()
             assert(b.end() == j);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/initializer_list.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/initializer_list.pass.cpp
index 9f99675896f208a5bc55b2353ed8ff2228e4af23..d510b86fed0769f0dcd2d13669b1dd1fbdba24c3 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/initializer_list.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::vector<bool> d = {true, false, false, true};
@@ -35,4 +35,6 @@ int main()
     assert(d[2] == false);
     assert(d[3] == true);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/initializer_list_alloc.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/initializer_list_alloc.pass.cpp
index 29164b598e666abf4b7cbfb068ef0c9187719dca..27d8420a6df7db599f7f42502ff248e01d234212 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/initializer_list_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/initializer_list_alloc.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::vector<bool, test_allocator<bool>> d({true, false, false, true}, test_allocator<bool>(3));
@@ -38,4 +38,6 @@ int main()
     assert(d[2] == false);
     assert(d[3] == true);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/insert_iter_initializer_list.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/insert_iter_initializer_list.pass.cpp
index 3760a9611bbd6eb11243a42f72ac5dfb14c52b93..519752da1030b3be4053ac121fa17f65149aeb85 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/insert_iter_initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/insert_iter_initializer_list.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::vector<bool> d(10, true);
@@ -59,4 +59,6 @@ int main()
     assert(d[12] == true);
     assert(d[13] == true);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/insert_iter_iter_iter.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/insert_iter_iter_iter.pass.cpp
index 7180bb8c28bf35349454502a07ade1f8f34bb698..b9a92189169e567dce8f9ad658ae5947a1a1724f 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/insert_iter_iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/insert_iter_iter_iter.pass.cpp
@@ -20,7 +20,7 @@
 #include "test_iterators.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<bool> v(100);
@@ -125,4 +125,6 @@ int main()
             assert(v[j] == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/insert_iter_size_value.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/insert_iter_size_value.pass.cpp
index 9e13af2ac7d2ec9708a5d5b54f8658845069aff4..5774ab5f6ca7bf1fe6b424d512db3bae073f013a 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/insert_iter_size_value.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/insert_iter_size_value.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<bool> v(100);
@@ -78,4 +78,6 @@ int main()
             assert(v[j] == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/insert_iter_value.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/insert_iter_value.pass.cpp
index 1c0e8ed03a820862df49e2a82c10a620dce96b0b..2502865c78e2b91044ce75cd0acad799f6a6a18a 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/insert_iter_value.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/insert_iter_value.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<bool> v(100);
@@ -74,4 +74,6 @@ int main()
             assert(v[j] == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/iterators.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/iterators.pass.cpp
index 0780d1dd093312a7277518bd9fa684a521d11036..7714e53b2cd5fdad0661d57bb8cb6e7e34b98e07 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/iterators.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/iterators.pass.cpp
@@ -22,7 +22,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef bool T;
@@ -120,4 +120,6 @@ int main()
         assert (ii1 - cii == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/move.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/move.pass.cpp
index e5752e0843782e49af7c7cc7a79820ebecae9d12..4de0604c6a7a10257e0cc0327f77abd345fcdcf9 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/move.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/move.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<bool, test_allocator<bool> > l(test_allocator<bool>(5));
@@ -89,4 +89,6 @@ int main()
         assert(a.get_data() == 42);
       }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/move_alloc.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/move_alloc.pass.cpp
index bcf57b6c2c3daa22ec0cd97449e8057dad21f328..f2ff5303b0fa5396a97d1f6d671ffc134d1f2f7a 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/move_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/move_alloc.pass.cpp
@@ -17,7 +17,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<bool, test_allocator<bool> > l(test_allocator<bool>(5));
@@ -71,4 +71,6 @@ int main()
         assert(l.empty());
         assert(l2.get_allocator() == min_allocator<bool>());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/move_assign_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/move_assign_noexcept.pass.cpp
index 60517e206536105728f11e1668d9e1e90102833f..6c7fcfca75c483a93058863efffb1907af50b067 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/move_assign_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/move_assign_noexcept.pass.cpp
@@ -56,7 +56,7 @@ struct some_alloc3
     typedef std::false_type is_always_equal;
 };
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -97,4 +97,6 @@ int main()
         static_assert(!std::is_nothrow_move_assignable<C>::value, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/move_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/move_noexcept.pass.cpp
index 8326e4c42715199afaf5b10c4ed0ab22b287bf17..a59e1a8eb94fe75a8d7548bb3c4c1caf1a427528 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/move_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/move_noexcept.pass.cpp
@@ -28,7 +28,7 @@ struct some_alloc
     some_alloc(const some_alloc&);
 };
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -56,4 +56,6 @@ int main()
         static_assert(!std::is_nothrow_move_constructible<C>::value, "");
 #endif
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/op_equal_initializer_list.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/op_equal_initializer_list.pass.cpp
index 5263fa3bd3ae2bb5d1ab1ade90fd7e1d6d177151..22384fe8d06c93b10d4b1f7ef8023ece8c256bfc 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/op_equal_initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/op_equal_initializer_list.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::vector<bool> d;
@@ -37,4 +37,6 @@ int main()
     assert(d[2] == false);
     assert(d[3] == true);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/push_back.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/push_back.pass.cpp
index 2e7d82d961bc0902e52e76dc0a4f4746817ae77e..438869be16cc31c132498372573af97c0fb48a5a 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/push_back.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/push_back.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         bool a[] = {0, 1, 1, 0, 1, 0, 0};
@@ -45,4 +45,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/reference.swap.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/reference.swap.pass.cpp
index 22e1091422561041f81133a52fcc5b239064d73b..c41bac188364cd7d86133e1e172ac561274a2721 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/reference.swap.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/reference.swap.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 
     bool a[] = {false, true, false, true};
@@ -35,4 +35,6 @@ int main()
     v.swap(r1, r2);
     assert( r1);
     assert(!r2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/reserve.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/reserve.pass.cpp
index b7430453fae5deb925c83df4e76f09afb85323da..039c1bc18fa34a64a005d63da84d809262d76162 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/reserve.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/reserve.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<bool> v;
@@ -50,4 +50,6 @@ int main()
         assert(v.capacity() >= 150);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/resize_size.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/resize_size.pass.cpp
index 3d926910ce70060c5a2351eac9caa6a6833741ff..53e83ac7effaddfabf1bdf35c9d4b9a701dafab8 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/resize_size.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/resize_size.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<bool> v(100);
@@ -46,4 +46,6 @@ int main()
         assert(v.capacity() >= 400);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/resize_size_value.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/resize_size_value.pass.cpp
index 061f8a505e4e1a12b9116b6e603e3a87944d7753..ef0cb6160c6a33569e281dab7be32c50b8b38ed4 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/resize_size_value.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/resize_size_value.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<bool> v(100);
@@ -48,4 +48,6 @@ int main()
             assert(v[i] == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/shrink_to_fit.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/shrink_to_fit.pass.cpp
index 988ce6e03bfbe697d9cc816c43db493c262333d5..59714d5fb5ccb6e764739bbafa21cbbd292724ca 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/shrink_to_fit.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/shrink_to_fit.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<bool> v(100);
@@ -34,4 +34,6 @@ int main()
         assert(v.size() >= 101);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/size.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/size.pass.cpp
index d8abef9893f1adeea4297b8bc2cc8de53288b545..db737c930c3596f0269d268c5958e2560fc48daf 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/size.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/size.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::vector<bool> C;
@@ -58,4 +58,6 @@ int main()
     assert(c.size() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/swap.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/swap.pass.cpp
index 9aa579d4a6d3ded3566c4ed707fa2f25dc0d7d9f..9ff11113d82c842bf0f778d5e589e4046f005e1c 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/swap.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/swap.pass.cpp
@@ -16,7 +16,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<bool> v1(100);
@@ -94,4 +94,6 @@ int main()
         assert(v[1] == true);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/swap_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/swap_noexcept.pass.cpp
index dbf0f821f136a062044d73079ea4090e958c7ee0..e346c29983f83e2d1bfced5dca44fc320d7095c6 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/swap_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/swap_noexcept.pass.cpp
@@ -52,7 +52,7 @@ struct some_alloc2
     typedef std::true_type is_always_equal;
 };
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -89,4 +89,6 @@ int main()
     }
 #endif // _LIBCPP_VERSION
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/types.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/types.pass.cpp
index 4736f8ac9761ce37638627a28de3e7f151b3729c..d15973a38b1b8a5f682f781974702726b2cdbeea 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/types.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/types.pass.cpp
@@ -67,7 +67,7 @@ test()
         std::reverse_iterator<typename C::const_iterator> >::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     test<test_allocator<bool> >();
     test<std::allocator<bool> >();
@@ -76,4 +76,6 @@ int main()
 #if TEST_STD_VER >= 11
     test<min_allocator<bool> >();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/vector_bool.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/vector_bool.pass.cpp
index c0d27e4d294602de4a42c995c19baaee29dc7e96..5f9ae3decb6ec647fd7d89831562325deafc5a67 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/vector_bool.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/vector_bool.pass.cpp
@@ -23,7 +23,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::vector<bool> T;
@@ -50,4 +50,6 @@ int main()
     assert(h(vb) != 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/allocator_mismatch.fail.cpp b/libcxx/test/std/containers/sequences/vector/allocator_mismatch.fail.cpp
index 001af629856d585bd57adacb007a9b44f427b82d..0c57f16be6c620c592840be748c65063bcd258b9 100644
--- a/libcxx/test/std/containers/sequences/vector/allocator_mismatch.fail.cpp
+++ b/libcxx/test/std/containers/sequences/vector/allocator_mismatch.fail.cpp
@@ -11,7 +11,9 @@
 
 #include <vector>
 
-int main()
+int main(int, char**)
 {
     std::vector<int, std::allocator<long> > v;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/contiguous.pass.cpp b/libcxx/test/std/containers/sequences/vector/contiguous.pass.cpp
index 2ac79be6ad170d7954e2e5d0669b18276c6fcae3..99d9d6ecae7a3d66b579a33230183023f3de4d4c 100644
--- a/libcxx/test/std/containers/sequences/vector/contiguous.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/contiguous.pass.cpp
@@ -23,7 +23,7 @@ void test_contiguous ( const C &c )
         assert ( *(c.begin() + static_cast<typename C::difference_type>(i)) == *(std::addressof(*c.begin()) + i));
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef int T;
@@ -48,4 +48,6 @@ int main()
     test_contiguous(C(9, 11.0, A{}));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/iterators.pass.cpp b/libcxx/test/std/containers/sequences/vector/iterators.pass.cpp
index f8b8ca3176bb6878c679407baba49fa6c90af07c..296c551f76f67bac0613d432c063533b78677b3d 100644
--- a/libcxx/test/std/containers/sequences/vector/iterators.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/iterators.pass.cpp
@@ -28,7 +28,7 @@ struct A
     int second;
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -166,4 +166,6 @@ int main()
         assert (ii1 - cii == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/types.pass.cpp b/libcxx/test/std/containers/sequences/vector/types.pass.cpp
index 101355bee7c2bc4f461bc27ffa564b8c6d37d9cb..0a04c25527a630f6a990e60f6df8fc35eba29f1c 100644
--- a/libcxx/test/std/containers/sequences/vector/types.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/types.pass.cpp
@@ -78,7 +78,7 @@ test()
         std::reverse_iterator<typename C::const_iterator> >::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     test<int, test_allocator<int> >();
     test<int*, std::allocator<int*> >();
@@ -104,4 +104,6 @@ int main()
 //         typename std::iterator_traits<typename C::const_iterator>::difference_type>::value), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.capacity/capacity.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.capacity/capacity.pass.cpp
index 58dccba224ac945b9483c0da2b4e2c0933e200fb..a8ee9f2296234e27a1ea987c667c169ddca63acc 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.capacity/capacity.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.capacity/capacity.pass.cpp
@@ -16,7 +16,7 @@
 #include "min_allocator.h"
 #include "asan_testing.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<int> v;
@@ -44,4 +44,6 @@ int main()
         assert(is_contiguous_container_asan_correct(v));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.capacity/empty.fail.cpp b/libcxx/test/std/containers/sequences/vector/vector.capacity/empty.fail.cpp
index 8085bd4846c7feb27b157862012db67ea64b4df0..0f7dc6c64cc009e00129caea2858b7d4fa214b09 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.capacity/empty.fail.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.capacity/empty.fail.cpp
@@ -20,8 +20,10 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     std::vector<int> c;
     c.empty();  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.capacity/empty.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.capacity/empty.pass.cpp
index 594b9e4f48d95d569a5733e055f7bc26dacffc82..cce2602bd360bec341b199a677efd6eb75277515 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.capacity/empty.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.capacity/empty.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::vector<int> C;
@@ -42,4 +42,6 @@ int main()
     assert(c.empty());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.capacity/max_size.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.capacity/max_size.pass.cpp
index 3e18d4a4d5bf2f92d0abf8671216e858ee81aeb6..c9cc6d5821c4f74241fa6df83a15afc68a74a113 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.capacity/max_size.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.capacity/max_size.pass.cpp
@@ -19,7 +19,7 @@
 #include "test_macros.h"
 
 
-int main() {
+int main(int, char**) {
   {
     typedef limited_allocator<int, 10> A;
     typedef std::vector<int, A> C;
@@ -44,4 +44,6 @@ int main() {
     assert(c.max_size() <= max_dist);
     assert(c.max_size() <= alloc_max_size(c.get_allocator()));
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.capacity/reserve.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.capacity/reserve.pass.cpp
index 48f57c99cb466e873c61906d21af8679264c9e3d..4cf3b2d338c05a2d7fb3c6816e903d59fbd0dbfb 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.capacity/reserve.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.capacity/reserve.pass.cpp
@@ -16,7 +16,7 @@
 #include "min_allocator.h"
 #include "asan_testing.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<int> v;
@@ -66,4 +66,6 @@ int main()
         assert(is_contiguous_container_asan_correct(v));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.capacity/resize_size.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.capacity/resize_size.pass.cpp
index d4b282518fe03254e33d6194b5476e5bd6db41dc..41188acb7d893d2dd6842fc287a9f373614082f6 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.capacity/resize_size.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.capacity/resize_size.pass.cpp
@@ -19,7 +19,7 @@
 #include "min_allocator.h"
 #include "asan_testing.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<int> v(100);
@@ -80,4 +80,6 @@ int main()
         assert(is_contiguous_container_asan_correct(v));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.capacity/resize_size_value.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.capacity/resize_size_value.pass.cpp
index 35b63756a31670c1e4d298ae68019c081aaafd1a..4d9f7931d8acaaf4dc2541d1529c200064af2154 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.capacity/resize_size_value.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.capacity/resize_size_value.pass.cpp
@@ -16,7 +16,7 @@
 #include "min_allocator.h"
 #include "asan_testing.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<int> v(100);
@@ -73,4 +73,6 @@ int main()
         assert(is_contiguous_container_asan_correct(v));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.capacity/shrink_to_fit.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.capacity/shrink_to_fit.pass.cpp
index 1b8d2815ccd77d0a4d182237b1cc7362c1b522ae..36125bb932c38190b703ea6cb8ea8ffa6582e249 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.capacity/shrink_to_fit.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.capacity/shrink_to_fit.pass.cpp
@@ -16,7 +16,7 @@
 #include "min_allocator.h"
 #include "asan_testing.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<int> v(100);
@@ -58,4 +58,6 @@ int main()
         assert(is_contiguous_container_asan_correct(v));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.capacity/size.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.capacity/size.pass.cpp
index 8944eca422ef04c48599763ac15d23106a38b68b..373a7069f3a914f3600ad4c775b60349940c0eb0 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.capacity/size.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.capacity/size.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::vector<int> C;
@@ -58,4 +58,6 @@ int main()
     assert(c.size() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.capacity/swap.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.capacity/swap.pass.cpp
index f66eafe25f5a1788973cf3a3aae852741270d9c4..e2fa0d8b92832d10ee11db0da21ab83e188508ff 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.capacity/swap.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.capacity/swap.pass.cpp
@@ -16,7 +16,7 @@
 #include "min_allocator.h"
 #include "asan_testing.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<int> v1(100);
@@ -46,4 +46,6 @@ int main()
         assert(is_contiguous_container_asan_correct(v2));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.cons/assign_copy.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.cons/assign_copy.pass.cpp
index 2c087fb498d1b63b45812a1f25404d9b31f2e97a..f6d8dd50b7e507ac6a3ebd8745e656f6ffd7df10 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.cons/assign_copy.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.cons/assign_copy.pass.cpp
@@ -15,7 +15,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<int, test_allocator<int> > l(3, 2, test_allocator<int>(5));
@@ -40,4 +40,6 @@ int main()
         assert(l2.get_allocator() == min_allocator<int>());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.cons/assign_initializer_list.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.cons/assign_initializer_list.pass.cpp
index c64c8bf3bce5bdd435381a3770114baa7e615a70..4673df9558de88abbd17e2af1537488625e3afac 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.cons/assign_initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.cons/assign_initializer_list.pass.cpp
@@ -30,7 +30,7 @@ void test ( Vec &v )
     assert(v[3] == 6);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::vector<int> V;
@@ -48,4 +48,6 @@ int main()
     test(d1);
     test(d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.cons/assign_iter_iter.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.cons/assign_iter_iter.pass.cpp
index 888ffb105d16ec9165ae4d50d1ef0ea74ff6162d..df8450210d8a20bbe3e2e3f7ba721067c7179c59 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.cons/assign_iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.cons/assign_iter_iter.pass.cpp
@@ -69,7 +69,9 @@ void test_emplaceable_concept() {
 
 
 
-int main()
+int main(int, char**)
 {
     test_emplaceable_concept();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.cons/assign_move.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.cons/assign_move.pass.cpp
index 1a915060c1a79bbb4248d909f3b68a1d3ced5830..4b70c7843f19ace84ea8ddf212117c0d9c0b1383 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.cons/assign_move.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.cons/assign_move.pass.cpp
@@ -19,7 +19,7 @@
 #include "min_allocator.h"
 #include "asan_testing.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<MoveOnly, test_allocator<MoveOnly> > l(test_allocator<MoveOnly>(5));
@@ -95,4 +95,6 @@ int main()
         assert(l2.get_allocator() == lo.get_allocator());
         assert(is_contiguous_container_asan_correct(l2));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.cons/assign_size_value.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.cons/assign_size_value.pass.cpp
index 4f05307223422c29122aabf98a5348284a6b7489..b85238db9a940150318247a053956cb8b752abe1 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.cons/assign_size_value.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.cons/assign_size_value.pass.cpp
@@ -29,7 +29,7 @@ void test ( Vec &v )
     assert(std::all_of(v.begin(), v.end(), is6));
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::vector<int> V;
@@ -50,4 +50,6 @@ int main()
     test(d2);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.cons/construct_default.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.cons/construct_default.pass.cpp
index c31b3c2faa5d87b4b6f746ccff31d0a7039cfe39..346c357d3f3ed72da8c8ac3e71a0577226727871 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.cons/construct_default.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.cons/construct_default.pass.cpp
@@ -60,7 +60,7 @@ test1(const typename C::allocator_type& a)
     LIBCPP_ASSERT(is_contiguous_container_asan_correct(c));
 }
 
-int main()
+int main(int, char**)
 {
     {
     test0<std::vector<int> >();
@@ -98,4 +98,6 @@ int main()
         assert(v.empty());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.cons/construct_iter_iter.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.cons/construct_iter_iter.pass.cpp
index 1623c8296be9cb06c9c1decae5e998c7a8d9250b..8f8ffa82c0c047031ed9b3a6afb8158735b73721 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.cons/construct_iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.cons/construct_iter_iter.pass.cpp
@@ -176,9 +176,11 @@ void test_ctor_with_different_value_type() {
 }
 
 
-int main() {
+int main(int, char**) {
   basic_test_cases();
   emplaceable_concept_tests(); // See PR34898
   test_ctor_under_alloc();
   test_ctor_with_different_value_type();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.cons/construct_iter_iter_alloc.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.cons/construct_iter_iter_alloc.pass.cpp
index 6cd319bc8a9324111bf629e5700dfdb9cf84c5e6..3a97b43b7e04200fef437bd72bfc7730b52da24a 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.cons/construct_iter_iter_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.cons/construct_iter_iter_alloc.pass.cpp
@@ -162,8 +162,10 @@ void test_ctor_under_alloc() {
 #endif
 }
 
-int main() {
+int main(int, char**) {
   basic_tests();
   emplaceable_concept_tests(); // See PR34898
   test_ctor_under_alloc();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.cons/construct_size.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.cons/construct_size.pass.cpp
index fe20a70369444f4a929dd023de113ddef2d416dd..f111220d3a4500df95c02c80195f4cc04d85a13c 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.cons/construct_size.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.cons/construct_size.pass.cpp
@@ -60,7 +60,7 @@ test(typename C::size_type n)
     test2<C> ( n );
 }
 
-int main()
+int main(int, char**)
 {
     test<std::vector<int> >(50);
     test<std::vector<DefaultOnly> >(500);
@@ -71,4 +71,6 @@ int main()
     test2<std::vector<DefaultOnly, test_allocator<DefaultOnly>> >( 100, test_allocator<DefaultOnly>(23));
     assert(DefaultOnly::count == 0);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.cons/construct_size_value.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.cons/construct_size_value.pass.cpp
index c8cd2f2a3c4d72a94df0f713182203a4b4d836bf..0839883a9b5b5942938a001437aedfaa7aeef555 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.cons/construct_size_value.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.cons/construct_size_value.pass.cpp
@@ -30,7 +30,7 @@ test(typename C::size_type n, const typename C::value_type& x)
         assert(*i == x);
 }
 
-int main()
+int main(int, char**)
 {
     test<std::vector<int> >(50, 3);
     // Add 1 for implementations that dynamically allocate a container proxy.
@@ -38,4 +38,6 @@ int main()
 #if TEST_STD_VER >= 11
     test<std::vector<int, min_allocator<int>> >(50, 3);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.cons/construct_size_value_alloc.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.cons/construct_size_value_alloc.pass.cpp
index c0bba42da4561eff3c38580e16afb49c833fb052..1de08853454f8760b62c43c6b6a5ef642614c5fd 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.cons/construct_size_value_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.cons/construct_size_value_alloc.pass.cpp
@@ -31,10 +31,12 @@ test(typename C::size_type n, const typename C::value_type& x,
         assert(*i == x);
 }
 
-int main()
+int main(int, char**)
 {
     test<std::vector<int> >(50, 3, std::allocator<int>());
 #if TEST_STD_VER >= 11
     test<std::vector<int, min_allocator<int>> >(50, 3, min_allocator<int>());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.cons/copy.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.cons/copy.pass.cpp
index 1542827e35beff45eba7a50e9aacb5fbb0712486..844da38416b0f8495bbf6d7864de7396a8d90844 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.cons/copy.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.cons/copy.pass.cpp
@@ -30,7 +30,7 @@ test(const C& x)
     LIBCPP_ASSERT(is_contiguous_container_asan_correct(c));
 }
 
-int main()
+int main(int, char**)
 {
     {
         int a[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 8, 7, 6, 5, 4, 3, 1, 0};
@@ -74,4 +74,6 @@ int main()
         assert(is_contiguous_container_asan_correct(v2));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.cons/copy_alloc.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.cons/copy_alloc.pass.cpp
index d54fc59f508d3e4df12873545cbe9755148ea176..79b484f78c7cc090f73e70464fbf522a1ddda436 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.cons/copy_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.cons/copy_alloc.pass.cpp
@@ -30,7 +30,7 @@ test(const C& x, const typename C::allocator_type& a)
     LIBCPP_ASSERT(is_contiguous_container_asan_correct(c));
 }
 
-int main()
+int main(int, char**)
 {
     {
         int a[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 8, 7, 6, 5, 4, 3, 1, 0};
@@ -62,4 +62,6 @@ int main()
         assert(l2.get_allocator() == min_allocator<int>());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.cons/deduct.fail.cpp b/libcxx/test/std/containers/sequences/vector/vector.cons/deduct.fail.cpp
index 0ce0bafbff4fd7091a38d18aa4700b604eaced84..beb10498c771f83eb45f71a8275d72a5a10d3c47 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.cons/deduct.fail.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.cons/deduct.fail.cpp
@@ -23,7 +23,7 @@
 #include <cstddef>
 
 
-int main()
+int main(int, char**)
 {
 //  Test the explicit deduction guides
 
@@ -36,4 +36,6 @@ int main()
 //      deque<allocator<int>, allocator<allocator<int>>>
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.cons/deduct.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.cons/deduct.pass.cpp
index 0ada98c0c9abccc104753c7df96fef6aa925a662..e6b59b40c8fb7ac2478d752f004a91bf232f7253 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.cons/deduct.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.cons/deduct.pass.cpp
@@ -29,7 +29,7 @@
 
 struct A {};
 
-int main()
+int main(int, char**)
 {
 
 //  Test the explicit deduction guides
@@ -112,4 +112,6 @@ int main()
     static_assert(std::is_same_v<decltype(vec)::allocator_type, std::allocator<bool>>, "");
     assert(vec.size() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.cons/default.recursive.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.cons/default.recursive.pass.cpp
index e7298ba85a06a286888d58622b60665205ded02f..1558ea4b619f4280cba253c882448eebc286f258 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.cons/default.recursive.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.cons/default.recursive.pass.cpp
@@ -17,6 +17,8 @@ struct X
     std::vector<X> q;
 };
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.cons/default_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.cons/default_noexcept.pass.cpp
index 24f78b28244f2a0e4458e6c1dcf9de74d0223848..91434964b2ca28d5e2609210ef18b62c94fb6010 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.cons/default_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.cons/default_noexcept.pass.cpp
@@ -29,7 +29,7 @@ struct some_alloc
     some_alloc(const some_alloc&);
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::vector<MoveOnly> C;
@@ -47,4 +47,6 @@ int main()
         typedef std::vector<MoveOnly, some_alloc<MoveOnly>> C;
         static_assert(!std::is_nothrow_default_constructible<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.cons/dtor_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.cons/dtor_noexcept.pass.cpp
index e02a7b029e23d602e487280522faf13352eabb7a..f4c05b6e2d56c9e7e0abd7d921dd58234af2c572 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.cons/dtor_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.cons/dtor_noexcept.pass.cpp
@@ -27,7 +27,7 @@ struct some_alloc
     ~some_alloc() noexcept(false);
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::vector<MoveOnly> C;
@@ -47,4 +47,6 @@ int main()
         static_assert(!std::is_nothrow_destructible<C>::value, "");
     }
 #endif // _LIBCPP_VERSION
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.cons/initializer_list.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.cons/initializer_list.pass.cpp
index a839e03666a22ca68c41053b44ca630d8297a5e5..168e3b58bd5a4b64f95148fbe47deba8ee3f8c88 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.cons/initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.cons/initializer_list.pass.cpp
@@ -17,7 +17,7 @@
 #include "min_allocator.h"
 #include "asan_testing.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::vector<int> d = {3, 4, 5, 6};
@@ -37,4 +37,6 @@ int main()
     assert(d[2] == 5);
     assert(d[3] == 6);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.cons/initializer_list_alloc.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.cons/initializer_list_alloc.pass.cpp
index f8ea034f7401162085e512ad3ffc934d21408d32..633b5c5e2ea121bb5d02f0aa77694574cfc288b8 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.cons/initializer_list_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.cons/initializer_list_alloc.pass.cpp
@@ -19,7 +19,7 @@
 #include "min_allocator.h"
 #include "asan_testing.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::vector<int, test_allocator<int>> d({3, 4, 5, 6}, test_allocator<int>(3));
@@ -41,4 +41,6 @@ int main()
     assert(d[2] == 5);
     assert(d[3] == 6);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.cons/move.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.cons/move.pass.cpp
index e5d625b5e3634f67682574100c288b6569236072..938857458b790f229dd7d1e43fee1617285daf8c 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.cons/move.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.cons/move.pass.cpp
@@ -21,7 +21,7 @@
 #include "min_allocator.h"
 #include "asan_testing.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<MoveOnly, test_allocator<MoveOnly> > l(test_allocator<MoveOnly>(5));
@@ -129,4 +129,6 @@ int main()
         assert(a.get_data() == 42);
       }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.cons/move_alloc.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.cons/move_alloc.pass.cpp
index dcea27a0d7aeb5ec67b226a8cbeb6ff160cb13b4..2f15a14e8c89d5ca72f112f754e30fed7c032ad4 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.cons/move_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.cons/move_alloc.pass.cpp
@@ -19,7 +19,7 @@
 #include "min_allocator.h"
 #include "asan_testing.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<MoveOnly, test_allocator<MoveOnly> > l(test_allocator<MoveOnly>(5));
@@ -93,4 +93,6 @@ int main()
         assert(l2.get_allocator() == min_allocator<MoveOnly>());
         assert(is_contiguous_container_asan_correct(l2));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.cons/move_assign_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.cons/move_assign_noexcept.pass.cpp
index 8eeb19eb43ad059b47edf7a9caeec3a8ab60195a..c5c5e29cda4f7a25c0e796b71f3354f41a292e87 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.cons/move_assign_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.cons/move_assign_noexcept.pass.cpp
@@ -57,7 +57,7 @@ struct some_alloc3
 };
 
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::vector<MoveOnly> C;
@@ -91,4 +91,6 @@ int main()
         static_assert(!std::is_nothrow_move_assignable<C>::value, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.cons/move_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.cons/move_noexcept.pass.cpp
index a9a554ad213bc6d63fa7aa76f1d6d1472d69aa70..1228414289f3ec2379892f3011616102a24d0bc7 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.cons/move_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.cons/move_noexcept.pass.cpp
@@ -28,7 +28,7 @@ struct some_alloc
     some_alloc(const some_alloc&);
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::vector<MoveOnly> C;
@@ -51,4 +51,6 @@ int main()
         static_assert(!std::is_nothrow_move_constructible<C>::value, "");
 #endif
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.cons/op_equal_initializer_list.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.cons/op_equal_initializer_list.pass.cpp
index 941f1e012b3c5d65605a9460308097ac95ba7c00..61c20b7c7f062317f00bb4f838deb4eba9b07747 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.cons/op_equal_initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.cons/op_equal_initializer_list.pass.cpp
@@ -18,7 +18,7 @@
 #include "min_allocator.h"
 #include "asan_testing.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::vector<int> d;
@@ -40,4 +40,6 @@ int main()
     assert(d[2] == 5);
     assert(d[3] == 6);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.data/data.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.data/data.pass.cpp
index cd176c7017b31799ce70f12b3d2e47cbc6b4b503..3477c5eb1bd0b78e0b9be823e23864e945a917a1 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.data/data.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.data/data.pass.cpp
@@ -25,7 +25,7 @@ struct Nasty {
     int i_;
     };
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<int> v;
@@ -59,4 +59,6 @@ int main()
         assert(is_contiguous_container_asan_correct(v));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.data/data_const.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.data/data_const.pass.cpp
index 33d973954e2bb6d2c21cdb9e383caca853d0a841..ec5016d2f6cbe97098c01d4959bcc010d7f57bcf 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.data/data_const.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.data/data_const.pass.cpp
@@ -25,7 +25,7 @@ struct Nasty {
     int i_;
     };
 
-int main()
+int main(int, char**)
 {
     {
         const std::vector<int> v;
@@ -59,4 +59,6 @@ int main()
         assert(is_contiguous_container_asan_correct(v));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.erasure/erase.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.erasure/erase.pass.cpp
index 3a96b55cadfaf91bfc0201331637b63835132bfb..00676b52dc609b404e7a0f6f5211741e37c6ff6a 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.erasure/erase.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.erasure/erase.pass.cpp
@@ -66,7 +66,7 @@ void test()
     test0(S({1,2,1}), opt(3), S({1,2,1}));
 }
 
-int main()
+int main(int, char**)
 {
     test<std::vector<int>>();
     test<std::vector<int, min_allocator<int>>> ();
@@ -74,4 +74,6 @@ int main()
 
     test<std::vector<long>>();
     test<std::vector<double>>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.erasure/erase_if.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.erasure/erase_if.pass.cpp
index f18c404837716645df0435869eef82c4d574cd30..10d66a29b4e4bc872aab8782ffd43f19d2c3b47b 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.erasure/erase_if.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.erasure/erase_if.pass.cpp
@@ -66,7 +66,7 @@ void test()
     test0(S({1,2,3}), False, S({1,2,3}));
 }
 
-int main()
+int main(int, char**)
 {
     test<std::vector<int>>();
     test<std::vector<int, min_allocator<int>>> ();
@@ -74,4 +74,6 @@ int main()
 
     test<std::vector<long>>();
     test<std::vector<double>>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.modifiers/clear.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.modifiers/clear.pass.cpp
index a1ce8f000261aead2e2ddc0f0f32983ba4c114ad..334c67adcfc6742c4df0622a6ac15e85d217006f 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.modifiers/clear.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.modifiers/clear.pass.cpp
@@ -17,7 +17,7 @@
 #include "min_allocator.h"
 #include "asan_testing.h"
 
-int main()
+int main(int, char**)
 {
     {
     int a[] = {1, 2, 3};
@@ -39,4 +39,6 @@ int main()
     LIBCPP_ASSERT(is_contiguous_container_asan_correct(c));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.modifiers/emplace.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.modifiers/emplace.pass.cpp
index 7acc90b5a69fb0ac6852417b826a9de0263275b1..1279fba4ce291172d89d172339b72334b9b31d5d 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.modifiers/emplace.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.modifiers/emplace.pass.cpp
@@ -52,7 +52,7 @@ public:
     double getd() const {return d_;}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<A> c;
@@ -132,4 +132,6 @@ int main()
         assert(c.back().geti() == 3);
         assert(c.back().getd() == 4.5);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.modifiers/emplace_back.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.modifiers/emplace_back.pass.cpp
index 6ddc88560d21f7b0126abf312fbf5f4edd91e968..435be207bb44b6511a6178aef901f018d86315d1 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.modifiers/emplace_back.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.modifiers/emplace_back.pass.cpp
@@ -53,7 +53,7 @@ public:
     double getd() const {return d_;}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<A> c;
@@ -144,4 +144,6 @@ int main()
         assert(c.size() == 2);
         assert(is_contiguous_container_asan_correct(c));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.modifiers/emplace_extra.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.modifiers/emplace_extra.pass.cpp
index 45835c338627d9caf26370507d106e33d8b33578..ec5f778565a6f788003ae3b83c4060df390b1259 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.modifiers/emplace_extra.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.modifiers/emplace_extra.pass.cpp
@@ -18,7 +18,7 @@
 #include "min_allocator.h"
 #include "asan_testing.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<int> v;
@@ -56,4 +56,6 @@ int main()
         assert(v[0] == 3);
         assert(is_contiguous_container_asan_correct(v));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.modifiers/erase_iter.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.modifiers/erase_iter.pass.cpp
index def3b350dd2649fb91002ead2a6df016eac82ee9..aac35f9f8114a33157e77e9ab72058870951ce78 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.modifiers/erase_iter.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.modifiers/erase_iter.pass.cpp
@@ -32,7 +32,7 @@ struct Throws {
 bool Throws::sThrows = false;
 #endif
 
-int main()
+int main(int, char**)
 {
     {
     int a1[] = {1, 2, 3};
@@ -99,4 +99,6 @@ int main()
     assert(v.size() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.modifiers/erase_iter_iter.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.modifiers/erase_iter_iter.pass.cpp
index aab348f08bf39e6f6a69c1bd5ff5f36ded16b0c3..7682000d75e778552dd7a637f5088b438286b87f 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.modifiers/erase_iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.modifiers/erase_iter_iter.pass.cpp
@@ -32,7 +32,7 @@ struct Throws {
 bool Throws::sThrows = false;
 #endif
 
-int main()
+int main(int, char**)
 {
     int a1[] = {1, 2, 3};
     {
@@ -152,4 +152,6 @@ int main()
     assert(v.size() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.modifiers/insert_iter_initializer_list.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.modifiers/insert_iter_initializer_list.pass.cpp
index 46b6c010abf8d0e176ee128dab54c21855c43ef8..30d0cd686a4e08b627ed09b82d41f93588220153 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.modifiers/insert_iter_initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.modifiers/insert_iter_initializer_list.pass.cpp
@@ -18,7 +18,7 @@
 #include "min_allocator.h"
 #include "asan_testing.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::vector<int> d(10, 1);
@@ -62,4 +62,6 @@ int main()
     assert(d[12] == 1);
     assert(d[13] == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.modifiers/insert_iter_iter_iter.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.modifiers/insert_iter_iter_iter.pass.cpp
index fadd09e3e5aa291ead6ce6bf84c3c1bfbaede3c1..74cb612aab0f90ead3daf6a47e945bb741ad16af 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.modifiers/insert_iter_iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.modifiers/insert_iter_iter_iter.pass.cpp
@@ -21,7 +21,7 @@
 #include "min_allocator.h"
 #include "asan_testing.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::vector<int> V;
@@ -171,4 +171,6 @@ int main()
             assert(v[j] == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.modifiers/insert_iter_rvalue.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.modifiers/insert_iter_rvalue.pass.cpp
index e2190fd885d04830940ea8a68c36c84d78951d92..780bd9c485fd76b75f575eabe5c64e1066f85e95 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.modifiers/insert_iter_rvalue.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.modifiers/insert_iter_rvalue.pass.cpp
@@ -21,7 +21,7 @@
 #include "min_allocator.h"
 #include "asan_testing.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<MoveOnly> v(100);
@@ -62,4 +62,6 @@ int main()
         for (++j; j < 101; ++j)
             assert(v[j] == MoveOnly());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.modifiers/insert_iter_size_value.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.modifiers/insert_iter_size_value.pass.cpp
index ddaa4fb6a35e082d5e3212d3cdeca28195356103..5b182f44d6adc9e5d8715e9ca4c3381b7935a8d3 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.modifiers/insert_iter_size_value.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.modifiers/insert_iter_size_value.pass.cpp
@@ -19,7 +19,7 @@
 #include "min_allocator.h"
 #include "asan_testing.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<int> v(100);
@@ -111,4 +111,6 @@ int main()
             assert(v[j] == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.modifiers/insert_iter_value.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.modifiers/insert_iter_value.pass.cpp
index 23f0030ab25cb381b435358d0c9389a7a8b42297..2edadd0fe7774b0e3192686c8ad4d67c57767210 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.modifiers/insert_iter_value.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.modifiers/insert_iter_value.pass.cpp
@@ -19,7 +19,7 @@
 #include "min_allocator.h"
 #include "asan_testing.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<int> v(100);
@@ -93,4 +93,6 @@ int main()
             assert(v[j] == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.modifiers/pop_back.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.modifiers/pop_back.pass.cpp
index c0784f7031ed9cb961139043d178f61890f3dae9..db2337c276ec3605735f5b386338d7c3baea8ae0 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.modifiers/pop_back.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.modifiers/pop_back.pass.cpp
@@ -18,7 +18,7 @@
 #include "min_allocator.h"
 
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<int> c;
@@ -37,4 +37,6 @@ int main()
         assert(c.size() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.modifiers/push_back.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.modifiers/push_back.pass.cpp
index e9bcf24116b8df359de181d83e84be9d68e04078..d22136ddbcbe70921309c1064ce947ec41304a61 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.modifiers/push_back.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.modifiers/push_back.pass.cpp
@@ -17,7 +17,7 @@
 #include "min_allocator.h"
 #include "asan_testing.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<int> c;
@@ -108,4 +108,6 @@ int main()
             assert(c[j] == j);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.modifiers/push_back_exception_safety.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.modifiers/push_back_exception_safety.pass.cpp
index 48152cb81cf15280fb4b7f8ae5ed7a47b9304228..9e25611290cc6452ca2ba9ade6d2683b009ab08f 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.modifiers/push_back_exception_safety.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.modifiers/push_back_exception_safety.pass.cpp
@@ -64,7 +64,7 @@ CMyClass::~CMyClass() {
 
 bool operator==(const CMyClass &lhs, const CMyClass &rhs) { return lhs.equal(rhs); }
 
-int main()
+int main(int, char**)
 {
     CMyClass instance(42);
     std::vector<CMyClass> vec;
@@ -85,4 +85,6 @@ int main()
         assert(is_contiguous_container_asan_correct(vec));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.modifiers/push_back_rvalue.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.modifiers/push_back_rvalue.pass.cpp
index 070cabe5c29698f1329585f8872082a0aeace91f..d876eb6170a12094f23104375e3ecd039bceb0c6 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.modifiers/push_back_rvalue.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.modifiers/push_back_rvalue.pass.cpp
@@ -20,7 +20,7 @@
 #include "min_allocator.h"
 #include "asan_testing.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<MoveOnly> c;
@@ -109,4 +109,6 @@ int main()
         for (int j = 0; static_cast<std::size_t>(j) < c.size(); ++j)
             assert(c[j] == MoveOnly(j));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.special/swap.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.special/swap.pass.cpp
index d107be98fb5dffeb6e0626797db82bcdaa6d9c31..2ded4fe750f66ee084578dcdbe25b06532e22e79 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.special/swap.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.special/swap.pass.cpp
@@ -18,7 +18,7 @@
 #include "min_allocator.h"
 #include "asan_testing.h"
 
-int main()
+int main(int, char**)
 {
     {
         int a1[] = {1, 3, 7, 9, 10};
@@ -178,4 +178,6 @@ int main()
         assert(is_contiguous_container_asan_correct(c2));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector/vector.special/swap_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.special/swap_noexcept.pass.cpp
index 06d89282f2a25afe9c789f896b09254087a2c2af..40205b67c3ce9cef113813bde3a334c41ee5f8b3 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.special/swap_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.special/swap_noexcept.pass.cpp
@@ -53,7 +53,7 @@ struct some_alloc2
     typedef std::true_type is_always_equal;
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::vector<MoveOnly> C;
@@ -85,4 +85,6 @@ int main()
         static_assert( noexcept(swap(std::declval<C&>(), std::declval<C&>())), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/iterator_difference_type.pass.cpp b/libcxx/test/std/containers/unord/iterator_difference_type.pass.cpp
index 3f0b61e5f226e4f358d9572fb3f32cec6ddad783..fc5ccbee34f22559782c1ec2f2ba80ca20f6bcfc 100644
--- a/libcxx/test/std/containers/unord/iterator_difference_type.pass.cpp
+++ b/libcxx/test/std/containers/unord/iterator_difference_type.pass.cpp
@@ -73,7 +73,7 @@ void testUnorderedSet() {
   }
 }
 
-int main() {
+int main(int, char**) {
   {
     typedef std::unordered_map<int, int> Map;
     typedef std::pair<const int, int> ValueTp;
@@ -150,4 +150,6 @@ int main() {
     testUnorderedSet<Set, ValueTp, min_pointer<const ValueTp>>();
   }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/allocator_mismatch.fail.cpp b/libcxx/test/std/containers/unord/unord.map/allocator_mismatch.fail.cpp
index 9dc9869eaf7d701dd40198bc5517b40c235b7856..7059220425dd904446d6c132d49953c718497ccd 100644
--- a/libcxx/test/std/containers/unord/unord.map/allocator_mismatch.fail.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/allocator_mismatch.fail.cpp
@@ -11,7 +11,9 @@
 
 #include <unordered_map>
 
-int main()
+int main(int, char**)
 {
     std::unordered_map<int, int, std::hash<int>, std::less<int>, std::allocator<long> > m;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/bucket.pass.cpp b/libcxx/test/std/containers/unord/unord.map/bucket.pass.cpp
index ae65ac887956a7ed70b3720c95fb05a06625b63f..522b70976509596be62d7e1b9c3a54667d9536fa 100644
--- a/libcxx/test/std/containers/unord/unord.map/bucket.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/bucket.pass.cpp
@@ -25,7 +25,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string> C;
@@ -74,4 +74,6 @@ int main()
         assert(false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/bucket_count.pass.cpp b/libcxx/test/std/containers/unord/unord.map/bucket_count.pass.cpp
index b2529a831adf2a60c4987e405a677c109a420bd8..ee1a125232b51008c9fc9dc61ea5e9cc9757a06c 100644
--- a/libcxx/test/std/containers/unord/unord.map/bucket_count.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/bucket_count.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string> C;
@@ -71,4 +71,6 @@ int main()
         assert(c.bucket_count() >= 8);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/bucket_size.pass.cpp b/libcxx/test/std/containers/unord/unord.map/bucket_size.pass.cpp
index 2edb6cc206cd325fe19e095e69871c8337c121e9..439d2b533bf404306fdc1f1b0bf673a06e31c1dc 100644
--- a/libcxx/test/std/containers/unord/unord.map/bucket_size.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/bucket_size.pass.cpp
@@ -25,7 +25,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string> C;
@@ -78,4 +78,6 @@ int main()
         assert(false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/compare.pass.cpp b/libcxx/test/std/containers/unord/unord.map/compare.pass.cpp
index 6c5891e1a8d51a033ea252662812b52381d8789b..7d6cbf9a8ad16634d2d633adf7bd201021d92c70 100644
--- a/libcxx/test/std/containers/unord/unord.map/compare.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/compare.pass.cpp
@@ -32,7 +32,7 @@ namespace std
     };
 }
 
-int main()
+int main(int, char**)
 {
     typedef std::unordered_map<Key, int> MapT;
     typedef MapT::iterator Iter;
@@ -42,4 +42,6 @@ int main()
     std::pair<Iter, bool> result = map.insert(std::make_pair(Key(0), 42));
     assert(result.second);
     assert(result.first->second == 42);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/count.pass.cpp b/libcxx/test/std/containers/unord/unord.map/count.pass.cpp
index bd754843cadfe31f29d30aa17dbd260d5095b185..1a1bea90b8268e7ef7d4ff8073053b39fd04ecbd 100644
--- a/libcxx/test/std/containers/unord/unord.map/count.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/count.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string> C;
@@ -61,4 +61,6 @@ int main()
         assert(c.count(5) == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/empty.fail.cpp b/libcxx/test/std/containers/unord/unord.map/empty.fail.cpp
index c4fa89e662db2800554ba396ef8484d4c3a742c1..283d6fa3e243bfa128c6b8bc9899e6089d7f4de7 100644
--- a/libcxx/test/std/containers/unord/unord.map/empty.fail.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/empty.fail.cpp
@@ -20,8 +20,10 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     std::unordered_map<int, int> c;
     c.empty();  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/empty.pass.cpp b/libcxx/test/std/containers/unord/unord.map/empty.pass.cpp
index 1dcba5cf70f678e6baa68650ca64ba9305caaaa6..da6d48df2d57c83e7c8f49e351b750d52bb708f5 100644
--- a/libcxx/test/std/containers/unord/unord.map/empty.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/empty.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::unordered_map<int, double> M;
@@ -42,4 +42,6 @@ int main()
     assert(m.empty());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/eq.pass.cpp b/libcxx/test/std/containers/unord/unord.map/eq.pass.cpp
index 99bd1fa67582f7d1ef0a580d25080a3264049d33..d284e822ade863ba7c05c4f23934e72e587f2928 100644
--- a/libcxx/test/std/containers/unord/unord.map/eq.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/eq.pass.cpp
@@ -24,7 +24,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string> C;
@@ -159,4 +159,6 @@ int main()
         assert(!(c1 != c2));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/equal_range_const.pass.cpp b/libcxx/test/std/containers/unord/unord.map/equal_range_const.pass.cpp
index a3b2b5c8a972a667a825adcdd9f2cc8aa13462c6..b9dd9a64e2ec2d1f0cfe97a856aebb285b8cb45c 100644
--- a/libcxx/test/std/containers/unord/unord.map/equal_range_const.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/equal_range_const.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string> C;
@@ -71,4 +71,6 @@ int main()
         assert(std::distance(r.first, r.second) == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/equal_range_non_const.pass.cpp b/libcxx/test/std/containers/unord/unord.map/equal_range_non_const.pass.cpp
index 505d355d7a366eac4e2f5178386f5a36db1cc563..029222d5caf8e67a0b07372d328d17e60e8b9c0c 100644
--- a/libcxx/test/std/containers/unord/unord.map/equal_range_non_const.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/equal_range_non_const.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string> C;
@@ -71,4 +71,6 @@ int main()
         assert(std::distance(r.first, r.second) == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/erase_if.pass.cpp b/libcxx/test/std/containers/unord/unord.map/erase_if.pass.cpp
index 5238d9ee0e89e892ac5edcab0288d41bf37c5a90..5498f454388b4f099ffe511ec15f79bc65d7a28c 100644
--- a/libcxx/test/std/containers/unord/unord.map/erase_if.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/erase_if.pass.cpp
@@ -67,7 +67,7 @@ void test()
     test0<S>({1,2,3}, False, {1,2,3});
 }
 
-int main()
+int main(int, char**)
 {
     test<std::unordered_map<int, int>>();
     test<std::unordered_map<int, int, std::hash<int>, std::equal_to<int>, min_allocator<std::pair<const int, int>>>> ();
@@ -75,5 +75,7 @@ int main()
 
     test<std::unordered_map<long, short>>();
     test<std::unordered_map<short, double>>();
+
+  return 0;
 }
 
diff --git a/libcxx/test/std/containers/unord/unord.map/find_const.pass.cpp b/libcxx/test/std/containers/unord/unord.map/find_const.pass.cpp
index 65c2a12088f50332f8be5032e451db08390339af..1d63b4be2ef08f689e7c234bc4d63072e59a7813 100644
--- a/libcxx/test/std/containers/unord/unord.map/find_const.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/find_const.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string> C;
@@ -67,4 +67,6 @@ int main()
         assert(i == c.cend());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/find_non_const.pass.cpp b/libcxx/test/std/containers/unord/unord.map/find_non_const.pass.cpp
index e6efa8e06429e17b002631c85c387bb42029fa94..58a9cd35afd469f771fa12d253d9d781c4801587 100644
--- a/libcxx/test/std/containers/unord/unord.map/find_non_const.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/find_non_const.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string> C;
@@ -67,4 +67,6 @@ int main()
         assert(i == c.end());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/incomplete_type.pass.cpp b/libcxx/test/std/containers/unord/unord.map/incomplete_type.pass.cpp
index f6faaac500ec94f2732d4ca6fd796bd3cee7096e..ddcd6e14c50b8d4cf07492a6f80d58c57f0b2762 100644
--- a/libcxx/test/std/containers/unord/unord.map/incomplete_type.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/incomplete_type.pass.cpp
@@ -31,6 +31,8 @@ struct A {
 
 inline bool operator==(A const& L, A const& R) { return &L == &R; }
 
-int main() {
+int main(int, char**) {
     A a;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/iterators.pass.cpp b/libcxx/test/std/containers/unord/unord.map/iterators.pass.cpp
index 609e7d7c4af9573a20e948efa06a3994b9960a3a..0b4e02e339f627ebeb6d0045a4beca32f5cfcff3 100644
--- a/libcxx/test/std/containers/unord/unord.map/iterators.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/iterators.pass.cpp
@@ -27,7 +27,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string> C;
@@ -126,4 +126,6 @@ int main()
         assert (!(cii != ii1 ));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/load_factor.pass.cpp b/libcxx/test/std/containers/unord/unord.map/load_factor.pass.cpp
index 418cdf7fd5f663a6894c0cc566c4b85cea514e60..7a5fde8a489543ab99279f122c9e06244569f9b9 100644
--- a/libcxx/test/std/containers/unord/unord.map/load_factor.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/load_factor.pass.cpp
@@ -23,7 +23,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string> C;
@@ -73,4 +73,6 @@ int main()
         assert(c.load_factor() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/local_iterators.pass.cpp b/libcxx/test/std/containers/unord/unord.map/local_iterators.pass.cpp
index f51df487856e9a32e2940ad5e23669bb08225e9a..e24e1811ac1d82272795c04e476bfb97d05701dd 100644
--- a/libcxx/test/std/containers/unord/unord.map/local_iterators.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/local_iterators.pass.cpp
@@ -25,7 +25,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string> C;
@@ -417,4 +417,6 @@ int main()
         assert(i->second == "four");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/max_bucket_count.pass.cpp b/libcxx/test/std/containers/unord/unord.map/max_bucket_count.pass.cpp
index d9c03128a3ab8613ecff97a0a48ca9e3594ddf7d..eb8f3e9d2ed5d8fa0bf9f92e1d4ce9a1f85b0147 100644
--- a/libcxx/test/std/containers/unord/unord.map/max_bucket_count.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/max_bucket_count.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string> C;
@@ -36,4 +36,6 @@ int main()
         assert(c.max_bucket_count() > 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/max_load_factor.pass.cpp b/libcxx/test/std/containers/unord/unord.map/max_load_factor.pass.cpp
index e57eb71d32a1cb1a34068fb32ac4de12f23664ee..8620dd1bd46ee0f05f3f915d163e1edfaa8a98a1 100644
--- a/libcxx/test/std/containers/unord/unord.map/max_load_factor.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/max_load_factor.pass.cpp
@@ -27,7 +27,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string> C;
@@ -65,4 +65,6 @@ int main()
         assert(false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/max_size.pass.cpp b/libcxx/test/std/containers/unord/unord.map/max_size.pass.cpp
index 3dc62d0b8aa76de5aeed562d0edbbb21482bdb00..7c2ec58de57f47c36ca63af3d126bc23fea6318d 100644
--- a/libcxx/test/std/containers/unord/unord.map/max_size.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/max_size.pass.cpp
@@ -20,7 +20,7 @@
 #include "test_allocator.h"
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
   typedef std::pair<const int, int> KV;
   {
@@ -49,4 +49,6 @@ int main()
       assert(c.max_size() <= max_dist);
       assert(c.max_size() <= alloc_max_size(c.get_allocator()));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/rehash.pass.cpp b/libcxx/test/std/containers/unord/unord.map/rehash.pass.cpp
index ff7b1b75f222bea3782742d9b0cbe8849c704f87..c8f079fb6178002436eb11d4f659f956416f73a6 100644
--- a/libcxx/test/std/containers/unord/unord.map/rehash.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/rehash.pass.cpp
@@ -37,7 +37,7 @@ void test(const C& c)
     assert(c.at(4) == "four");
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string> C;
@@ -100,4 +100,6 @@ int main()
         test(c);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/reserve.pass.cpp b/libcxx/test/std/containers/unord/unord.map/reserve.pass.cpp
index 983c872379a9a18b4e910de82dc8c6d77ce69bb1..622a9691e4575a8ada38009dde19be29a26fc57e 100644
--- a/libcxx/test/std/containers/unord/unord.map/reserve.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/reserve.pass.cpp
@@ -46,7 +46,7 @@ void reserve_invariant(size_t n) // LWG #2156
     }
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string> C;
@@ -104,4 +104,6 @@ int main()
     }
 #endif
     reserve_invariant(20);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/size.pass.cpp b/libcxx/test/std/containers/unord/unord.map/size.pass.cpp
index 22a922d1fbe24ec6d5c6ae77833829226394d530..d4e7cb97f6491a6739ef390772b3db8268f42db8 100644
--- a/libcxx/test/std/containers/unord/unord.map/size.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/size.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::unordered_map<int, double> M;
@@ -58,4 +58,6 @@ int main()
     assert(m.size() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/swap_member.pass.cpp b/libcxx/test/std/containers/unord/unord.map/swap_member.pass.cpp
index 2763940f8c50887b111c3b03b1412d4cbf7b90cf..ff9b32e3ea27ffe7790ebc5c68719d8fed39d854 100644
--- a/libcxx/test/std/containers/unord/unord.map/swap_member.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/swap_member.pass.cpp
@@ -25,7 +25,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef test_hash<std::hash<int> > Hash;
@@ -567,4 +567,6 @@ int main()
         assert(c2.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/types.pass.cpp b/libcxx/test/std/containers/unord/unord.map/types.pass.cpp
index 1c8c86b5d93ccf82da704cefebb3f52f97de8f1a..e194f69f8ac1701f911fea0cbdcfc12e96820c31 100644
--- a/libcxx/test/std/containers/unord/unord.map/types.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/types.pass.cpp
@@ -32,7 +32,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<char, short> C;
@@ -68,4 +68,6 @@ int main()
         static_assert((std::is_same<C::difference_type, std::ptrdiff_t>::value), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/allocator.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/allocator.pass.cpp
index 0c1ee685b520450712f43b2fb0b52bd3cc1ead17..8f1d7561b2470974b19f66126214775256973555 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/allocator.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/allocator.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<NotConstructible, NotConstructible,
@@ -126,4 +126,6 @@ int main()
     }
 #endif
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/assign_copy.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/assign_copy.pass.cpp
index 2820e66a82f9425a72934f7b33293d303cfef992..a5a67bcc29d2197d1d4c03ea7cf1cbeee20fc278 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/assign_copy.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/assign_copy.pass.cpp
@@ -28,7 +28,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef test_allocator<std::pair<const int, std::string> > A;
@@ -185,4 +185,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/assign_init.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/assign_init.pass.cpp
index 8f651b92983432b5b895b30c00f1822f587aa325..e9e62898886224605185e2a9714c0dea3beee848 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/assign_init.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/assign_init.pass.cpp
@@ -27,7 +27,7 @@
 #include "../../../test_hash.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::allocator<std::pair<const int, std::string> > A;
@@ -93,4 +93,6 @@ int main()
         assert(fabs(c.load_factor() - (float)c.size()/c.bucket_count()) < FLT_EPSILON);
         assert(c.max_load_factor() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/assign_move.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/assign_move.pass.cpp
index ab0df753a3148bd0e2219deb21914c519aa92aa1..87b80cef1c48ad5a3b6f15738c4099fea0cf1235 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/assign_move.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/assign_move.pass.cpp
@@ -29,7 +29,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef test_allocator<std::pair<const int, std::string> > A;
@@ -214,4 +214,6 @@ int main()
         assert(c.max_load_factor() == 1);
         assert(c0.size() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/compare_copy_constructible.fail.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/compare_copy_constructible.fail.cpp
index 1a3cbc38668dac8b553f0feb49b98bdc54144169..2591c99f4e4f8f11d830b6f35a5dffc37f9a4dfc 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/compare_copy_constructible.fail.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/compare_copy_constructible.fail.cpp
@@ -26,6 +26,8 @@ private:
     };
 
 
-int main() {
+int main(int, char**) {
     std::unordered_map<int, int, std::hash<int>, Comp<int> > m;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/copy.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/copy.pass.cpp
index c8e1d73d0ffbc9af21a7484750b8989057a53884..ee4bc43a54aa91a1cb2d62cbbd8b28b034c19909 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/copy.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/copy.pass.cpp
@@ -27,7 +27,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string,
@@ -148,4 +148,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/copy_alloc.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/copy_alloc.pass.cpp
index 939e30c8211d39e9ef36dbf788a6d973a1897cff..8e7a3a0796e2466fe1935f131efde514e2a761b4 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/copy_alloc.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/copy_alloc.pass.cpp
@@ -27,7 +27,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string,
@@ -148,4 +148,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/default.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/default.pass.cpp
index fe95ce8f8652564d2ab90cf50bc704ab68cfa2c2..bda7d24a6fd459a964c21aab6b032e15c1731095 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/default.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/default.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<NotConstructible, NotConstructible,
@@ -108,4 +108,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/default_noexcept.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/default_noexcept.pass.cpp
index cf00bb116be04648755187e0f4aa80eafc8b15da..a4af74a89a119072d3647a4d05753ccc5227135c 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/default_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/default_noexcept.pass.cpp
@@ -45,7 +45,7 @@ struct some_hash
     std::size_t operator()(T const&) const;
 };
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -72,4 +72,6 @@ int main()
                                                          some_comp<MoveOnly>> C;
         static_assert(!std::is_nothrow_default_constructible<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/dtor_noexcept.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/dtor_noexcept.pass.cpp
index 247e57600d6496483998a380bd042ae17faa9057..4f4331fa0878c3d4f676aca1fb8af8ca4ebd045f 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/dtor_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/dtor_noexcept.pass.cpp
@@ -38,7 +38,7 @@ struct some_hash
     std::size_t operator()(T const&) const;
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<MoveOnly, MoveOnly> C;
@@ -65,4 +65,6 @@ int main()
         static_assert(!std::is_nothrow_destructible<C>::value, "");
     }
 #endif // _LIBCPP_VERSION
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/hash_copy_constructible.fail.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/hash_copy_constructible.fail.cpp
index 3da62824078833b1a6ed1d98d1d5bb7bee52a986..026e319fcbdc900bd33f82a1b8f614dba09cc1c0 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/hash_copy_constructible.fail.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/hash_copy_constructible.fail.cpp
@@ -26,6 +26,8 @@ private:
 };
 
 
-int main() {
+int main(int, char**) {
     std::unordered_map<int, int, Hash<int> > m;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/init.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/init.pass.cpp
index 6b00cb7c515092c5a93b68ce6aa7f322058c310e..00b4a2f0bc2a848b981d2db226f8dd35d1690b6e 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/init.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/init.pass.cpp
@@ -29,7 +29,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string,
@@ -159,4 +159,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif // TEST_STD_VER > 11
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/init_size.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/init_size.pass.cpp
index 702b9231ea2b2206baf2f96c08e4f5e1dbe8c85f..f1dbad9feca9fdbe31c40c371daa27d2ec7dd915 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/init_size.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/init_size.pass.cpp
@@ -29,7 +29,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string,
@@ -97,4 +97,6 @@ int main()
         assert(std::fabs(c.load_factor() - (float)c.size()/c.bucket_count()) < FLT_EPSILON);
         assert(c.max_load_factor() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/init_size_hash.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/init_size_hash.pass.cpp
index 57f6dca546d9b5a1bd34c9fc531dfc3b55662ddc..c0c3d5c5b8a2a04cac8b6d0ee0d9395b53b2001e 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/init_size_hash.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/init_size_hash.pass.cpp
@@ -29,7 +29,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string,
@@ -99,4 +99,6 @@ int main()
         assert(std::fabs(c.load_factor() - (float)c.size()/c.bucket_count()) < FLT_EPSILON);
         assert(c.max_load_factor() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/init_size_hash_equal.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/init_size_hash_equal.pass.cpp
index d8d073a4d55f8e00b507aa56262d9bdf0d6a48b2..5c87af0a1e0b0407bc47d3949ac8fe856380dfd1 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/init_size_hash_equal.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/init_size_hash_equal.pass.cpp
@@ -30,7 +30,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string,
@@ -102,4 +102,6 @@ int main()
         assert(std::fabs(c.load_factor() - (float)c.size()/c.bucket_count()) < FLT_EPSILON);
         assert(c.max_load_factor() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/init_size_hash_equal_allocator.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/init_size_hash_equal_allocator.pass.cpp
index 0bce91b3ac470b503854043068a14135a46f6d70..5ab0366da29de8b59e34e342c59d67c271874c82 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/init_size_hash_equal_allocator.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/init_size_hash_equal_allocator.pass.cpp
@@ -30,7 +30,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string,
@@ -140,4 +140,6 @@ int main()
         assert(std::fabs(c.load_factor() - (float)c.size()/c.bucket_count()) < FLT_EPSILON);
         assert(c.max_load_factor() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/move.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/move.pass.cpp
index fdcd596e939df019a39911d50dca936dfeeff730..d4eed3c03be10c546132dabdfd5971f313d505c0 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/move.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/move.pass.cpp
@@ -29,7 +29,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string,
@@ -176,4 +176,6 @@ int main()
         assert(s2.size() == 2);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/move_alloc.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/move_alloc.pass.cpp
index 82e83ba482ba54629689299d29f7ae137e246ca1..be72227dabe04e6583e486702a5472de29c04740 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/move_alloc.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/move_alloc.pass.cpp
@@ -29,7 +29,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<int, std::string> P;
@@ -195,4 +195,6 @@ int main()
 
         assert(c0.empty());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/move_assign_noexcept.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/move_assign_noexcept.pass.cpp
index 71e913f27563a8eb4c2a3204139f77f44fcf7d4d..78ac7d787c28bb9f5704b3e0eb81e3cbeaa45cc0 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/move_assign_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/move_assign_noexcept.pass.cpp
@@ -44,7 +44,7 @@ struct some_hash
     std::size_t operator()(T const&) const;
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<MoveOnly, MoveOnly> C;
@@ -71,4 +71,6 @@ int main()
                                                          some_comp<MoveOnly>> C;
         static_assert(!std::is_nothrow_move_assignable<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/move_noexcept.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/move_noexcept.pass.cpp
index 09fefc4baf40d1cdb4c917c2d760e5118ee8bea9..62175145de9cd36d7899e8ab95a722133bee530e 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/move_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/move_noexcept.pass.cpp
@@ -41,7 +41,7 @@ struct some_hash
     std::size_t operator()(T const&) const;
 };
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -68,4 +68,6 @@ int main()
                                                          some_comp<MoveOnly>> C;
         static_assert(!std::is_nothrow_move_constructible<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/range.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/range.pass.cpp
index 002a39a861c87314ac2032c5230bfd22fe5e36b9..a6d87150846fb926c8447ed22558eda48499710c 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/range.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/range.pass.cpp
@@ -30,7 +30,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string,
@@ -169,4 +169,6 @@ int main()
     }
 #endif
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/range_size.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/range_size.pass.cpp
index e9ce1a29f2d4f92b7d6b81315515aaba9386d16f..66e0ac3a7698b0f6c359b714b68243fa5200bbdb 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/range_size.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/range_size.pass.cpp
@@ -30,7 +30,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string,
@@ -104,4 +104,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/range_size_hash.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/range_size_hash.pass.cpp
index 5240d2b5246302c654ca834a933b82b95ccfc521..62a590736bf78fd417c1578d6e40a538cdb4b7f2 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/range_size_hash.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/range_size_hash.pass.cpp
@@ -31,7 +31,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string,
@@ -107,4 +107,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/range_size_hash_equal.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/range_size_hash_equal.pass.cpp
index a8f69b235c919bee7a603a452c81a249b484eb07..70e391d466383c724d00692bca83b647c75f8d45 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/range_size_hash_equal.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/range_size_hash_equal.pass.cpp
@@ -31,7 +31,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string,
@@ -109,4 +109,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/range_size_hash_equal_allocator.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/range_size_hash_equal_allocator.pass.cpp
index 9c8f221f306c5df9902c40e38591120f391451d8..1f29c5414ead5ab9a23ad9a490cab19e2882b63d 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/range_size_hash_equal_allocator.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/range_size_hash_equal_allocator.pass.cpp
@@ -32,7 +32,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string,
@@ -150,4 +150,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/size.fail.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/size.fail.cpp
index 50252dd5b8881e4c5ea56b39be96cd5a3e320b23..9a715b6a1bb9cbe8f855f16fe62c1c225bb164c8 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/size.fail.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/size.fail.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<NotConstructible, NotConstructible,
@@ -66,4 +66,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/size.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/size.pass.cpp
index d9af5a3226e1aad50c1f3c10046827ca905e8530..41cfc7104fa3fe99beefafa380d281bcbd4708bb 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/size.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/size.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<NotConstructible, NotConstructible,
@@ -66,4 +66,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/size_hash.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/size_hash.pass.cpp
index 2c69847d90b08f07a671ee50d02ee14fdcc866a1..f97ee39fbef34aa4fed881fe9374430bc8d15704 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/size_hash.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/size_hash.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<NotConstructible, NotConstructible,
@@ -70,4 +70,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/size_hash_equal.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/size_hash_equal.pass.cpp
index b47f309f9d6b9f28ad90070bbafe1c41a949a27d..8c306364ed84786013d8b14e6f61cbee0a676d31 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/size_hash_equal.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/size_hash_equal.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<NotConstructible, NotConstructible,
@@ -72,4 +72,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/size_hash_equal_allocator.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/size_hash_equal_allocator.pass.cpp
index 1e821b8c668b04ce2fb8b75ff594d5a8e05d0003..40b9d01a203bb0e693c4106446aaf58068a86036 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/size_hash_equal_allocator.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.cnstr/size_hash_equal_allocator.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<NotConstructible, NotConstructible,
@@ -96,4 +96,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.elem/at.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.elem/at.pass.cpp
index 11db9bff726a7078720dcf29aa7fcd5d792aea03..fe6ef8bc7e85cade5df17fe2d37cfb454c536602 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.elem/at.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.elem/at.pass.cpp
@@ -24,7 +24,7 @@
 #include "min_allocator.h"
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string> C;
@@ -140,4 +140,6 @@ int main()
 #endif
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.elem/index.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.elem/index.pass.cpp
index 4ddb9f986a7686b310d7a0ebe8d7e0b453051ba5..ff83f1d6842b663f848025584c37711859fb325e 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.elem/index.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.elem/index.pass.cpp
@@ -28,7 +28,7 @@
 #include "container_test_types.h"
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string> C;
@@ -159,4 +159,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.elem/index_tuple.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.elem/index_tuple.pass.cpp
index feea53ecdab114fc94fe64cd8e597c3c4896a20d..4719b5583b31e91deb05895d99543a440fd1d2c1 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.elem/index_tuple.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.elem/index_tuple.pass.cpp
@@ -28,8 +28,10 @@ struct my_hash
     size_t operator()(const tuple<int,int>&) const {return 0;}
 };
 
-int main()
+int main(int, char**)
 {
     unordered_map<tuple<int,int>, size_t, my_hash> m;
     m[make_tuple(2,3)]=7;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/clear.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/clear.pass.cpp
index 6b0f03d9c287423e36fa9b09595291fa55afd81b..64fe72ecdacdbcedc1d9517ebc0fa53c83e19fff 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/clear.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/clear.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string> C;
@@ -60,4 +60,6 @@ int main()
         assert(c.size() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/emplace.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/emplace.pass.cpp
index 2ea264b53439f049c25510dad77790abb104bf60..63a269601f093c32833f77e85f484bcf3210057b 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/emplace.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/emplace.pass.cpp
@@ -23,7 +23,7 @@
 #include "../../../Emplaceable.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, Emplaceable> C;
@@ -74,4 +74,6 @@ int main()
         assert(r.first->first == 5);
         assert(r.first->second == Emplaceable(6, 7));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/emplace_hint.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/emplace_hint.pass.cpp
index a130d65c0ce61091734c319125838f8b15b19c5f..01e8d9c6fab7bcc5c71d8622e0fa1e4b95b8f210 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/emplace_hint.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/emplace_hint.pass.cpp
@@ -24,7 +24,7 @@
 #include "../../../Emplaceable.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, Emplaceable> C;
@@ -71,4 +71,6 @@ int main()
         assert(r->first == 5);
         assert(r->second == Emplaceable(6, 7));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_const_iter.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_const_iter.pass.cpp
index 78e70fbba4b93850cd623512fb07781ee21e61dd..1d0b18bf1d47ebc603bc0e2d620420cb453cad2c 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_const_iter.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_const_iter.pass.cpp
@@ -30,7 +30,7 @@ struct TemplateConstructor
 bool operator==(const TemplateConstructor&, const TemplateConstructor&) { return false; }
 struct Hash { size_t operator() (const TemplateConstructor &) const { return 0; } };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string> C;
@@ -89,4 +89,6 @@ int main()
             m.erase(it);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_iter_db1.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_iter_db1.pass.cpp
index b923752ef5800eb6718f8c9c388ae892151a7d20..38ba03d5e88f6439d7c9242e99b2cf6e25faa106 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_iter_db1.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_iter_db1.pass.cpp
@@ -17,7 +17,7 @@
 #include <unordered_map>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<int, int> P;
@@ -31,8 +31,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_iter_db2.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_iter_db2.pass.cpp
index fcc499ebf8fa6dfed7845d47ce9d6460f9fe5a30..887f7859b3e72f4edfd837e46815c79c7b860da4 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_iter_db2.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_iter_db2.pass.cpp
@@ -19,7 +19,7 @@
 #include <cstdlib>
 #include <exception>
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<int, int> P;
@@ -34,8 +34,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_iter_iter_db1.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_iter_iter_db1.pass.cpp
index fd9931ad2a0c547571eb38d362ac490a2c1af70a..15c6745adc95ff917ea4a6220a5b1fbb3d244778 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_iter_iter_db1.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_iter_iter_db1.pass.cpp
@@ -19,7 +19,7 @@
 #include <exception>
 #include <cstdlib>
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<int, int> P;
@@ -33,8 +33,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_iter_iter_db2.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_iter_iter_db2.pass.cpp
index 9f64445af0bbbd132d08533739bf11cff0f171b6..0ae0674adb79daae791b88a77ef17cf69f598bf4 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_iter_iter_db2.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_iter_iter_db2.pass.cpp
@@ -19,7 +19,7 @@
 #include <exception>
 #include <cstdlib>
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<int, int> P;
@@ -33,8 +33,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_iter_iter_db3.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_iter_iter_db3.pass.cpp
index 16cf5367fd42ff866ecf0798c140266fb167f9f4..134d075ec6ec19ab90e6373c5e203ea1b328742e 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_iter_iter_db3.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_iter_iter_db3.pass.cpp
@@ -19,7 +19,7 @@
 #include <exception>
 #include <cstdlib>
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<int, int> P;
@@ -33,8 +33,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_iter_iter_db4.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_iter_iter_db4.pass.cpp
index 2c59093458fa0c5fd0ca167be1f5d61f3c25c621..17745175bae1a5144964bac49c5d47c466df015e 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_iter_iter_db4.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_iter_iter_db4.pass.cpp
@@ -19,7 +19,7 @@
 #include <exception>
 #include <cstdlib>
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<int, int> P;
@@ -32,8 +32,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_key.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_key.pass.cpp
index aa2dea3d9edd4bc5152286b4c4c2b1a54788ce28..305d149a583749eac15ec6cb12a4429a67d8ce16 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_key.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_key.pass.cpp
@@ -38,7 +38,7 @@ bool only_deletions ( const Unordered &whole, const Unordered &part ) {
 #endif
 
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string> C;
@@ -174,4 +174,6 @@ int main()
     assert (only_deletions (m, m2));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_range.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_range.pass.cpp
index 5c2c676f2fb381d15b9ecaa687e9f05e0c92b523..839d65733dea5b219f4352ee28f88ac97bcbb01b 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_range.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/erase_range.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string> C;
@@ -95,4 +95,6 @@ int main()
         assert(k == c.end());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/extract_iterator.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/extract_iterator.pass.cpp
index 332eea13fb6f7388fafdb435815f31a3380b7d0b..3ad30510f92c02594dfd38ded51ae040fa6fe9e4 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/extract_iterator.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/extract_iterator.pass.cpp
@@ -40,7 +40,7 @@ void test(Container& c)
     assert(c.size() == 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
         using map_type = std::unordered_map<int, int>;
@@ -63,4 +63,6 @@ int main()
         min_alloc_map m = {{1, 1}, {2, 2}, {3, 3}, {4, 4}, {5, 5}, {6, 6}};
         test(m);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/extract_key.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/extract_key.pass.cpp
index 3272a438393b9daa981d5ae4878c91c421efb80f..4d6c24e6e996c7dbb74702fc4420f0df54e7833e 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/extract_key.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/extract_key.pass.cpp
@@ -45,7 +45,7 @@ void test(Container& c, KeyTypeIter first, KeyTypeIter last)
     }
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::unordered_map<int, int> m = {{1,1}, {2,2}, {3,3}, {4,4}, {5,5}, {6,6}};
@@ -72,4 +72,6 @@ int main()
         int keys[] = {1, 2, 3, 4, 5, 6};
         test(m, std::begin(keys), std::end(keys));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_and_emplace_allocator_requirements.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_and_emplace_allocator_requirements.pass.cpp
index f84e98c2babb0d1f0e44a54f3410533363cb46b1..71d456e6619d1333d87972e69e061eca0b87cbb1 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_and_emplace_allocator_requirements.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_and_emplace_allocator_requirements.pass.cpp
@@ -21,10 +21,12 @@
 #include "container_test_types.h"
 #include "../../../map_allocator_requirement_test_templates.h"
 
-int main()
+int main(int, char**)
 {
   testMapInsert<TCT::unordered_map<> >();
   testMapInsertHint<TCT::unordered_map<> >();
   testMapEmplace<TCT::unordered_map<> >();
   testMapEmplaceHint<TCT::unordered_map<> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_const_lvalue.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_const_lvalue.pass.cpp
index 3b4b7db1dafbbfeba9ac92edca73dd1cd160fa30..eb505218fdd1d46ba7bb75669849f80947623211 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_const_lvalue.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_const_lvalue.pass.cpp
@@ -65,7 +65,7 @@ void do_insert_cv_test()
     assert(r.first->second == 3);
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<double, int> M;
@@ -78,4 +78,6 @@ int main()
         do_insert_cv_test<M>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_hint_const_lvalue.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_hint_const_lvalue.pass.cpp
index 60c5d359c73de0a86c9301db00fec391d371da63..b1b77eb9c184ed80c7f24a2f7768c9bb974fe4d1 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_hint_const_lvalue.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_hint_const_lvalue.pass.cpp
@@ -56,7 +56,7 @@ void do_insert_hint_const_lvalue_test()
     assert(r->second == 4);
 }
 
-int main()
+int main(int, char**)
 {
     do_insert_hint_const_lvalue_test<std::unordered_map<double, int> >();
 #if TEST_STD_VER >= 11
@@ -80,4 +80,6 @@ int main()
         assert(false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_hint_rvalue.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_hint_rvalue.pass.cpp
index 4670fbfbed83d00b639dfd53ee5add296d5811b9..b7374d1a6eeac3e0c02e8a2d068b24468c821d66 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_hint_rvalue.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_hint_rvalue.pass.cpp
@@ -28,7 +28,7 @@
 #include "MoveOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<double, int> C;
@@ -173,4 +173,6 @@ int main()
         assert(false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_init.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_init.pass.cpp
index 20b5fb649c80d0516234e22afec266db3831928b..27e8747348e7cded0826f2a8d8b088a448a35bc2 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_init.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_init.pass.cpp
@@ -23,7 +23,7 @@
 #include "test_iterators.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string> C;
@@ -66,4 +66,6 @@ int main()
         assert(c.at(3) == "three");
         assert(c.at(4) == "four");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_node_type.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_node_type.pass.cpp
index 5840950d7a28681b31b472dc376e7e078f8e0c7b..24d0a23a59ff3cc9e2e48ab8245bb4fd9ac87eef 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_node_type.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_node_type.pass.cpp
@@ -74,10 +74,12 @@ void test(Container& c)
     }
 }
 
-int main()
+int main(int, char**)
 {
     std::unordered_map<int, int> m;
     test(m);
     std::unordered_map<int, int, std::hash<int>, std::equal_to<int>, min_allocator<std::pair<const int, int>>> m2;
     test(m2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_node_type_hint.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_node_type_hint.pass.cpp
index 3a97868804aa7c217bcd45a15c326f303c6fd353..21ccb88caf0bb8fd6c8bae3f5152ec9008490331 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_node_type_hint.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_node_type_hint.pass.cpp
@@ -54,10 +54,12 @@ void test(Container& c)
     }
 }
 
-int main()
+int main(int, char**)
 {
     std::unordered_map<int, int> m;
     test(m);
     std::unordered_map<int, int, std::hash<int>, std::equal_to<int>, min_allocator<std::pair<const int, int>>> m2;
     test(m2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_or_assign.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_or_assign.pass.cpp
index 5c02fc1290dc8f6a891bf488a9015de265ce766d..7fc3ff187be432d2f9dad7ae6419e1204e8658d9 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_or_assign.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_or_assign.pass.cpp
@@ -61,7 +61,7 @@ namespace std {
     };
 }
 
-int main()
+int main(int, char**)
 {
 
     { // pair<iterator, bool> insert_or_assign(const key_type& k, M&& obj);
@@ -188,4 +188,6 @@ int main()
         assert(r->second.get() == 5);  // value
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_range.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_range.pass.cpp
index a70703b5fa6d2cd40018ce3ebec0d923a418e475..1d51bdb4fbc436b4b70be883dca435681914562e 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_range.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_range.pass.cpp
@@ -22,7 +22,7 @@
 #include "test_iterators.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<int, std::string> C;
@@ -67,4 +67,6 @@ int main()
         assert(c.at(4) == "four");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_rvalue.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_rvalue.pass.cpp
index ed0a2a58df8e02ca94464a675f1a29b114d8d566..1f8528ab5b1673c1db57650449f63615bd71378d 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_rvalue.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/insert_rvalue.pass.cpp
@@ -24,7 +24,7 @@
 #include "MoveOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_map<double, int> C;
@@ -172,4 +172,6 @@ int main()
         assert(r.first->first == 5.5);
         assert(r.first->second == 4);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/merge.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/merge.pass.cpp
index 17be66154a1ca74486b1d098dfdf0b15fc259ec7..1437d46d2e287726d9a489558e01a59cac6b8da1 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/merge.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/merge.pass.cpp
@@ -49,7 +49,7 @@ struct throw_hasher
 };
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         std::unordered_map<int, int> src{{1, 0}, {3, 0}, {5, 0}};
@@ -153,4 +153,5 @@ int main()
             first.merge(std::move(second));
         }
     }
+    return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/try.emplace.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/try.emplace.pass.cpp
index dbdb1b89bf66f8c52dfb53672e66ffd349b149a0..c3ee0050a26a1ee632aca6f884e0fc3d01f719b6 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/try.emplace.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.modifiers/try.emplace.pass.cpp
@@ -60,7 +60,7 @@ namespace std {
     };
 }
 
-int main()
+int main(int, char**)
 {
 
     { // pair<iterator, bool> try_emplace(const key_type& k, Args&&... args);
@@ -185,4 +185,6 @@ int main()
         assert(r->first.get()  == 3); // key
         assert(r->second.get() == 4); // value
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.swap/db_swap_1.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.swap/db_swap_1.pass.cpp
index e47e7b6600f46d7f3daf928c2430bc2e69429a38..67a49d4bb8bf921793f03fb8f5eb1fdf262de800 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.swap/db_swap_1.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.swap/db_swap_1.pass.cpp
@@ -21,7 +21,7 @@
 #include <unordered_map>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
 #if _LIBCPP_DEBUG >= 1
     {
@@ -40,4 +40,6 @@ int main()
         assert(false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.swap/swap_noexcept.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.swap/swap_noexcept.pass.cpp
index 2522270fd7ae0a94af4b12287eaa65bf7715b25a..44ee7be490da19ea1044492f3a3f04d6d3dc9d87 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.swap/swap_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.swap/swap_noexcept.pass.cpp
@@ -119,7 +119,7 @@ struct some_alloc3
 };
 
 
-int main()
+int main(int, char**)
 {
     typedef std::pair<const MoveOnly, MoveOnly> MapType;
     {
@@ -188,4 +188,6 @@ int main()
     }
 #endif // _LIBCPP_VERSION
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.map/unord.map.swap/swap_non_member.pass.cpp b/libcxx/test/std/containers/unord/unord.map/unord.map.swap/swap_non_member.pass.cpp
index 9966bcd4f9db780ed6394b975e6f6c2e99732c62..7852394cdfbb8db4b05ace54324c432f8d5397f3 100644
--- a/libcxx/test/std/containers/unord/unord.map/unord.map.swap/swap_non_member.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.map/unord.map.swap/swap_non_member.pass.cpp
@@ -25,7 +25,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef test_hash<std::hash<int> > Hash;
@@ -567,4 +567,6 @@ int main()
         assert(c2.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/allocator_mismatch.fail.cpp b/libcxx/test/std/containers/unord/unord.multimap/allocator_mismatch.fail.cpp
index f1e7a2a96f5d61f114f83fa6e0f7cc406638aae0..ba24ca3cc9562a40c707cdbbd96bdf2f9cd110a5 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/allocator_mismatch.fail.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/allocator_mismatch.fail.cpp
@@ -11,7 +11,9 @@
 
 #include <unordered_map>
 
-int main()
+int main(int, char**)
 {
     std::unordered_multimap<int, int, std::hash<int>, std::less<int>, std::allocator<long> > m;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/bucket.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/bucket.pass.cpp
index 7b10eb86beb9f3e803816a52987aaf1134634bfc..c6c8b217cc4b9d150059d2e11da999782b39b75c 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/bucket.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/bucket.pass.cpp
@@ -25,7 +25,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string> C;
@@ -74,4 +74,6 @@ int main()
         assert(false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/bucket_count.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/bucket_count.pass.cpp
index 340c1dcc2c2c6c5151d2cc95d548cd64d3492706..9c0735719094489a059d222464b7e2111c288821 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/bucket_count.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/bucket_count.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string> C;
@@ -44,4 +44,6 @@ int main()
         const C c(std::begin(a), std::end(a));
         assert(c.bucket_count() >= 8);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/bucket_size.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/bucket_size.pass.cpp
index b7c7d653f5fa6fc5d681917899b1b518b6774abf..f491975215342efa10cbc0306d1007c9c1f26aa9 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/bucket_size.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/bucket_size.pass.cpp
@@ -25,7 +25,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string> C;
@@ -82,4 +82,6 @@ int main()
         assert(false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/count.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/count.pass.cpp
index 15134dd0f228c7d3194d3747485ab26cf13741fe..4a6ec5d6576e8c0184bc608ef49b08b9bbbd015b 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/count.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/count.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string> C;
@@ -67,4 +67,6 @@ int main()
         assert(c.count(5) == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/db_iterators_7.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/db_iterators_7.pass.cpp
index 2cffa13a4e052403f58ff57c568dd764bcc5286c..463b49938efbc3b8fa5e66eac1683c0529eb5082 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/db_iterators_7.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/db_iterators_7.pass.cpp
@@ -23,7 +23,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::unordered_multimap<int, std::string> C;
@@ -52,8 +52,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.multimap/db_iterators_8.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/db_iterators_8.pass.cpp
index 62da82f2d10692d7b9b24f4223fe0e00faf6a8fb..38395e5f9605c491358d6df2aa57747b44e2c749 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/db_iterators_8.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/db_iterators_8.pass.cpp
@@ -23,7 +23,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::unordered_multimap<int, std::string> C;
@@ -48,8 +48,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.multimap/db_local_iterators_7.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/db_local_iterators_7.pass.cpp
index a609b5dd0cc0fe590bf0fc740c6e0b5646d1a170..04d8b3ff06c55915e21135b7a63d30a58ebc171d 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/db_local_iterators_7.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/db_local_iterators_7.pass.cpp
@@ -23,7 +23,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::unordered_multimap<int, std::string> C;
@@ -49,8 +49,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.multimap/db_local_iterators_8.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/db_local_iterators_8.pass.cpp
index a397cad563ed85e63eb1780dad5abf8230a84fd7..69ef06993dcf062971335c72283ca77c16d406a5 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/db_local_iterators_8.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/db_local_iterators_8.pass.cpp
@@ -23,7 +23,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::unordered_multimap<int, std::string> C;
@@ -46,8 +46,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.multimap/empty.fail.cpp b/libcxx/test/std/containers/unord/unord.multimap/empty.fail.cpp
index 93ec56e94f759ccc1a7f0c0d95d423e44f67001a..4eb7bfc9c36c47c4880b51a37c6ff7121b6f29b3 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/empty.fail.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/empty.fail.cpp
@@ -20,8 +20,10 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     std::unordered_multimap<int, int> c;
     c.empty();  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/empty.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/empty.pass.cpp
index 58f4e602f9b627023dc1886eb7b2bd99be3c19c5..6189b7f0e3dedcd89794ae920196fb8a585b7d6f 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/empty.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/empty.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::unordered_multimap<int, double> M;
@@ -42,4 +42,6 @@ int main()
     assert(m.empty());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/eq.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/eq.pass.cpp
index 85dfb00923da4689e449efb882c342a93da1d3fe..5751916875fd1e06c10d94c73f4f152ffc13b7dc 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/eq.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/eq.pass.cpp
@@ -24,7 +24,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string> C;
@@ -177,4 +177,6 @@ int main()
         assert(!(c1 != c2));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/equal_range_const.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/equal_range_const.pass.cpp
index 88686a1fd3b983f6d10eaad9880de738eaa83f9b..148081be7be6abb1d5c1d5d71b21d2c5bb0ad27f 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/equal_range_const.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/equal_range_const.pass.cpp
@@ -21,7 +21,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string> C;
@@ -100,4 +100,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/equal_range_non_const.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/equal_range_non_const.pass.cpp
index 5e833c978ada1631a439ee7e7e309c5da5fb5401..5da87166bdab4d6efc42ea244a17656c5a62a282 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/equal_range_non_const.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/equal_range_non_const.pass.cpp
@@ -21,7 +21,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string> C;
@@ -100,4 +100,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/erase_if.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/erase_if.pass.cpp
index ef44cd81bf86e2dca300a68615b4d35bdf9828c4..2cec092056da2c15f8e788a69ed1460fc08a71c5 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/erase_if.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/erase_if.pass.cpp
@@ -78,7 +78,7 @@ void test()
     test0<S>({1,2,3}, False, {1,2,3});
 }
 
-int main()
+int main(int, char**)
 {
     test<std::unordered_multimap<int, int>>();
     test<std::unordered_multimap<int, int, std::hash<int>, std::equal_to<int>, min_allocator<std::pair<const int, int>>>> ();
@@ -86,4 +86,6 @@ int main()
 
     test<std::unordered_multimap<long, short>>();
     test<std::unordered_multimap<short, double>>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/find_const.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/find_const.pass.cpp
index c48d6ffff1d3b4477232141084546646aa68b5ff..271bf9d0c6085c64410d5a1ec9c86037dcf8a790 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/find_const.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/find_const.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string> C;
@@ -67,4 +67,6 @@ int main()
         assert(i == c.cend());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/find_non_const.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/find_non_const.pass.cpp
index b8975ef09acd41110ae7a1944521332b39f6e844..3e642e346f14950a86c2c80bfebfc1e529563da6 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/find_non_const.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/find_non_const.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string> C;
@@ -67,4 +67,6 @@ int main()
         assert(i == c.end());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/incomplete.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/incomplete.pass.cpp
index 77f03f51fc75779d1dc82345aab67c3d18ef0461..6ea4931299b6dfa067dee97460d114ca5a2434cd 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/incomplete.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/incomplete.pass.cpp
@@ -31,6 +31,8 @@ struct A {
 
 inline bool operator==(A const& L, A const& R) { return &L == &R; }
 
-int main() {
+int main(int, char**) {
     A a;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/iterators.fail.cpp b/libcxx/test/std/containers/unord/unord.multimap/iterators.fail.cpp
index aed2f713879c10b94f09a0bc8245401c1755ce4c..0c1b50fac059c4355131dd584db1eb17a8d8e3b3 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/iterators.fail.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/iterators.fail.cpp
@@ -25,7 +25,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string> C;
@@ -67,4 +67,6 @@ int main()
         assert(std::distance(c.begin(), c.end()) == c.size());
         assert(std::distance(c.cbegin(), c.cend()) == c.size());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/iterators.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/iterators.pass.cpp
index e669be6f3b880045ffb546a81d6aba701b34025f..5fd52beebbc7423b93f53639528310052b29d8f7 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/iterators.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/iterators.pass.cpp
@@ -27,7 +27,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string> C;
@@ -132,4 +132,6 @@ int main()
         assert (!(cii != ii1 ));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/load_factor.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/load_factor.pass.cpp
index f1624616ec40a239cbab3d00b782f4df5d006162..ae8a8403b8594961daaa296a6ad9bde26eeb289d 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/load_factor.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/load_factor.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string> C;
@@ -72,4 +72,6 @@ int main()
         assert(c.load_factor() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/local_iterators.fail.cpp b/libcxx/test/std/containers/unord/unord.multimap/local_iterators.fail.cpp
index 313c9e3782d6bdcb04510c3fad5ca02f9e4da268..f5af791804bddff0a575ad546e5a83f2ba3b82e7 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/local_iterators.fail.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/local_iterators.fail.cpp
@@ -25,7 +25,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string> C;
@@ -284,4 +284,6 @@ int main()
         j = c.cend(b);
         assert(std::distance(i, j) == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/local_iterators.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/local_iterators.pass.cpp
index 61815a9c67357dbf4a5598d291633cc057af2cb7..b5dd2d4b0fd03ac1488421dcd53d5c52aef973ed 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/local_iterators.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/local_iterators.pass.cpp
@@ -26,7 +26,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string> C;
@@ -658,4 +658,6 @@ int main()
         assert(std::distance(i, j) == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/max_bucket_count.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/max_bucket_count.pass.cpp
index b2442ff87250e6259acafe494c4bb78071d0b016..c55f4de8d44de3b51eb4db885d263f852d5786a3 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/max_bucket_count.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/max_bucket_count.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string> C;
@@ -35,4 +35,6 @@ int main()
         assert(c.max_bucket_count() > 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/max_load_factor.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/max_load_factor.pass.cpp
index a75052ebdb1c43b7bee73bc3fe108acff1c1ce64..ed46b681b7d5b58b6120d7d0b0329d8f9fc4eaf9 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/max_load_factor.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/max_load_factor.pass.cpp
@@ -25,7 +25,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string> C;
@@ -63,4 +63,6 @@ int main()
         assert(false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/max_size.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/max_size.pass.cpp
index 5ed732902bf147080b41e5715f4949586b562e5e..d03cf67ae7c693e850f337daa6c8f4bb6413d8bc 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/max_size.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/max_size.pass.cpp
@@ -20,7 +20,7 @@
 #include "test_allocator.h"
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
   typedef std::pair<const int, int> KV;
   {
@@ -51,4 +51,6 @@ int main()
       assert(c.max_size() <= max_dist);
       assert(c.max_size() <= alloc_max_size(c.get_allocator()));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/rehash.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/rehash.pass.cpp
index aa8996a1a7a8abc4b42ab300f8cd45077b27b1f3..99538e32d8276b3cfc5b6e0cb0cb7d53a5d9ce94 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/rehash.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/rehash.pass.cpp
@@ -81,7 +81,7 @@ void test(const C& c)
     assert(std::fabs(c.load_factor() - (float)c.size()/c.bucket_count()) < FLT_EPSILON);
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string> C;
@@ -144,4 +144,6 @@ int main()
         test(c);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/reserve.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/reserve.pass.cpp
index 1771faa60c48becf51e9dd4cd5285be9888e49d6..811ac97fb4a26418f9cf9096befc778be2844c56 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/reserve.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/reserve.pass.cpp
@@ -61,7 +61,7 @@ void reserve_invariant(size_t n) // LWG #2156
     }
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string> C;
@@ -119,4 +119,6 @@ int main()
     }
 #endif
     reserve_invariant(20);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/scary.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/scary.pass.cpp
index 321c38ceb26dcb08f26e114bc225dcd76b5187de..4c4b1cd110e0abded6167414414ecea57fae2dc2 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/scary.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/scary.pass.cpp
@@ -14,11 +14,13 @@
 
 #include <unordered_map>
 
-int main()
+int main(int, char**)
 {
     typedef std::unordered_map<int, int> M1;
     typedef std::unordered_multimap<int, int> M2;
     M2::iterator i;
     M1::iterator j = i;
     ((void)j);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/size.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/size.pass.cpp
index c24d93b5bfce1ecc9dc84081eba4ea1b2f19d0d3..493b8d757cfddced235ce2da75202d6e605631c6 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/size.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/size.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::unordered_multimap<int, double> M;
@@ -58,4 +58,6 @@ int main()
     assert(m.size() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/swap_member.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/swap_member.pass.cpp
index f57d821094f992aa1e487739e1a4338f306050a1..75806df9791783d14815232c0519955d60be4e83 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/swap_member.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/swap_member.pass.cpp
@@ -27,7 +27,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef test_hash<std::hash<int> > Hash;
@@ -653,4 +653,6 @@ int main()
         assert(c2.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/types.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/types.pass.cpp
index 5e7e1451b3706c5d378b9fa052408d9c7a44b2ba..2cb74a1545d7f2528a0875eed0f9f7fa47c24390 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/types.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/types.pass.cpp
@@ -32,7 +32,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<char, short> C;
@@ -68,4 +68,6 @@ int main()
         static_assert((std::is_same<C::difference_type, std::ptrdiff_t>::value), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/allocator.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/allocator.pass.cpp
index dadd81765a9bec978bff822e06b6e4a828e64439..e15999f183eead468ca1c79520135a09df392d2f 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/allocator.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/allocator.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<NotConstructible, NotConstructible,
@@ -126,4 +126,6 @@ int main()
     }
 #endif
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/assign_copy.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/assign_copy.pass.cpp
index 3b2b0cba703181b7bc15d45a23d7ea70441c7688..191dec98e5817b64dd66e710de33ad46e5e82a40 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/assign_copy.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/assign_copy.pass.cpp
@@ -28,7 +28,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef test_allocator<std::pair<const int, std::string> > A;
@@ -227,4 +227,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/assign_init.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/assign_init.pass.cpp
index cae8605dbb20f68660dc0da27c51cb171010ef82..5947905a62e4668c06e7df383f0799316b3dc572 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/assign_init.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/assign_init.pass.cpp
@@ -28,7 +28,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef test_allocator<std::pair<const int, std::string> > A;
@@ -142,4 +142,6 @@ int main()
         assert(fabs(c.load_factor() - (float)c.size()/c.bucket_count()) < FLT_EPSILON);
         assert(c.max_load_factor() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/assign_move.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/assign_move.pass.cpp
index f918721113dd4bcc4e471bb00e8f164902ad47cc..21c791a814f20b9c5711bc171552eb8a40166996 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/assign_move.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/assign_move.pass.cpp
@@ -29,7 +29,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef test_allocator<std::pair<const int, std::string> > A;
@@ -291,4 +291,6 @@ int main()
         assert(fabs(c.load_factor() - (float)c.size()/c.bucket_count()) < FLT_EPSILON);
         assert(c.max_load_factor() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/compare_copy_constructible.fail.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/compare_copy_constructible.fail.cpp
index 7438bf5301c0da3ae7a3e5385e0132667be9b302..fe288035fd02fcd70e8b13c41d765e5eb3461cff 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/compare_copy_constructible.fail.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/compare_copy_constructible.fail.cpp
@@ -26,6 +26,8 @@ private:
     };
 
 
-int main() {
+int main(int, char**) {
     std::unordered_multimap<int, int, std::hash<int>, Comp<int> > m;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/copy.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/copy.pass.cpp
index 7747aef541d41e55646d5f219c195c8557e0df2d..d570162222fd8fabdfb458589bbf539e33a6f9a7 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/copy.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/copy.pass.cpp
@@ -27,7 +27,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string,
@@ -190,4 +190,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/copy_alloc.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/copy_alloc.pass.cpp
index 41b5f537d9990641948e3ae1cbb76b7498dc094d..ebd047184845ab81b1c2f768d7d2ff1bd08984fc 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/copy_alloc.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/copy_alloc.pass.cpp
@@ -27,7 +27,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string,
@@ -190,4 +190,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/default.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/default.pass.cpp
index 3cd4da37e1e634bade7cf19902a32f846a16c150..dea7a46043839df65f9ccfda61460967efdb9558 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/default.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/default.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<NotConstructible, NotConstructible,
@@ -108,4 +108,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/default_noexcept.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/default_noexcept.pass.cpp
index 4866dde5d8666176ebdaae8a00614e0e14e1927d..5a54f61b503024a0abf304969762dc15673b7f1b 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/default_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/default_noexcept.pass.cpp
@@ -44,7 +44,7 @@ struct some_hash
     std::size_t operator()(T const&) const;
 };
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -71,4 +71,6 @@ int main()
                                                          some_comp<MoveOnly>> C;
         static_assert(!std::is_nothrow_default_constructible<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/dtor_noexcept.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/dtor_noexcept.pass.cpp
index f276bf77731feeaf2fb6fe562e611c8f6a5cae70..8f677edcb9c0d705dcdfb0eaf5ff22f6d2ee5aa4 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/dtor_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/dtor_noexcept.pass.cpp
@@ -37,7 +37,7 @@ struct some_hash
     std::size_t operator()(T const&) const;
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<MoveOnly, MoveOnly> C;
@@ -64,4 +64,6 @@ int main()
         static_assert(!std::is_nothrow_destructible<C>::value, "");
     }
 #endif // _LIBCPP_VERSION
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/hash_copy_constructible.fail.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/hash_copy_constructible.fail.cpp
index f6b8cb23e1805c1923d2da29b5feed3bd7240218..2681710c94d011a745a5dffea3cf81efc0eee9b1 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/hash_copy_constructible.fail.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/hash_copy_constructible.fail.cpp
@@ -26,6 +26,8 @@ private:
     };
 
 
-int main() {
+int main(int, char**) {
     std::unordered_multimap<int, int, Hash<int> > m;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/init.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/init.pass.cpp
index 43fb0f971ccc3a5ae69f72bd25bee2c481a52805..aba32bfeb84f386170f21328e4a5184c031de29f 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/init.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/init.pass.cpp
@@ -29,7 +29,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string,
@@ -251,4 +251,6 @@ int main()
         assert(!(c.get_allocator() == A()));
     }
 #endif // TEST_STD_VER > 11
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/init_size.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/init_size.pass.cpp
index 37bf73b5ca1d677f71f7af412860250a993e9483..194daf9f956f14b2a6692660e094a08d41cc42ed 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/init_size.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/init_size.pass.cpp
@@ -29,7 +29,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string,
@@ -141,4 +141,6 @@ int main()
         assert(c.key_eq() == test_compare<std::equal_to<int> >());
         assert((c.get_allocator() == min_allocator<std::pair<const int, std::string> >()));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/init_size_hash.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/init_size_hash.pass.cpp
index 9fbc5893fe98e8942098144f2feecf3b14e922f0..4613e3ca554134d354671f0b33d8ed02f5ac9729 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/init_size_hash.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/init_size_hash.pass.cpp
@@ -29,7 +29,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string,
@@ -143,4 +143,6 @@ int main()
         assert(c.key_eq() == test_compare<std::equal_to<int> >());
         assert((c.get_allocator() == min_allocator<std::pair<const int, std::string> >()));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/init_size_hash_equal.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/init_size_hash_equal.pass.cpp
index 398103dee0930f132fe9912d0cb30917e19054eb..582b68b94e2b36b7e71029a965cbaf2d66a0c764 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/init_size_hash_equal.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/init_size_hash_equal.pass.cpp
@@ -30,7 +30,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string,
@@ -146,4 +146,6 @@ int main()
         assert(c.key_eq() == test_compare<std::equal_to<int> >(9));
         assert((c.get_allocator() == min_allocator<std::pair<const int, std::string> >()));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/init_size_hash_equal_allocator.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/init_size_hash_equal_allocator.pass.cpp
index 2f81c2a01cbd512f5cc2532956a832a3ff5a879a..9019d9221d012ea9972a90ac8697509acb51ce73 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/init_size_hash_equal_allocator.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/init_size_hash_equal_allocator.pass.cpp
@@ -30,7 +30,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string,
@@ -207,4 +207,6 @@ int main()
         assert(c.key_eq() == test_compare<std::equal_to<int> >(9));
         assert(c.get_allocator() == A{});
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/move.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/move.pass.cpp
index 4bfc4d3b7ac09f687845e38087c84584bb399efd..bfa2327e598b90d1fd85822994fb5fef2366cc09 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/move.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/move.pass.cpp
@@ -29,7 +29,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string,
@@ -221,4 +221,6 @@ int main()
         assert(s2.size() == 2);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/move_alloc.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/move_alloc.pass.cpp
index 2b711513bf9f5889ca1462c5c885e670d88040cb..d99c2ad9deaf0466f18f6c07a4f31cbe2b93c073 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/move_alloc.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/move_alloc.pass.cpp
@@ -31,7 +31,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<int, std::string> P;
@@ -289,4 +289,6 @@ int main()
 
         assert(c0.empty());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/move_assign_noexcept.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/move_assign_noexcept.pass.cpp
index 649dfd94b819b59425810e313f0830a56969b5c1..e6f7f4c999bf51c17d44caa90e91e0dcee110cd4 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/move_assign_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/move_assign_noexcept.pass.cpp
@@ -43,7 +43,7 @@ struct some_hash
     std::size_t operator()(T const&) const;
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<MoveOnly, MoveOnly> C;
@@ -70,4 +70,6 @@ int main()
                                                          some_comp<MoveOnly>> C;
         static_assert(!std::is_nothrow_move_assignable<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/move_noexcept.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/move_noexcept.pass.cpp
index c1f6d3143fa41de24480161b7832fe7c37dbcb73..68ec2600aeba4d282a450964588739eef988ed11 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/move_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/move_noexcept.pass.cpp
@@ -40,7 +40,7 @@ struct some_hash
     std::size_t operator()(T const&) const;
 };
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -67,4 +67,6 @@ int main()
                                                          some_comp<MoveOnly>> C;
         static_assert(!std::is_nothrow_move_constructible<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/range.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/range.pass.cpp
index 3158236a46153ed097a06d4868944a1db92e2355..4b916fa419a511ab834c91bb24c82a52710dd5c1 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/range.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/range.pass.cpp
@@ -30,7 +30,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string,
@@ -262,4 +262,6 @@ int main()
     }
 #endif
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/range_size.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/range_size.pass.cpp
index 731207ef69fddc8d375491d83395436f18cf924f..aa45e074702849957c8078798aa3c32f9311496d 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/range_size.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/range_size.pass.cpp
@@ -30,7 +30,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string,
@@ -148,4 +148,6 @@ int main()
         assert((c.get_allocator() == min_allocator<std::pair<const int, std::string> >()));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/range_size_hash.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/range_size_hash.pass.cpp
index a009d1372bc2ecb2f608183639135c189f8aa8e3..ee9de7a4ec3659698e6a8c37b63bfffaa0a82719 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/range_size_hash.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/range_size_hash.pass.cpp
@@ -31,7 +31,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string,
@@ -151,4 +151,6 @@ int main()
         assert((c.get_allocator() == min_allocator<std::pair<const int, std::string> >()));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/range_size_hash_equal.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/range_size_hash_equal.pass.cpp
index b6548bcc5439975b4c671dac8263ebcc0a159e72..54c1f1e9d85672a1b430a3cfd83765a6b6eb9ff1 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/range_size_hash_equal.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/range_size_hash_equal.pass.cpp
@@ -31,7 +31,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string,
@@ -153,4 +153,6 @@ int main()
         assert((c.get_allocator() == min_allocator<std::pair<const int, std::string> >()));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/range_size_hash_equal_allocator.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/range_size_hash_equal_allocator.pass.cpp
index 288ad6dd3657a906fed1567831d8f43e2b9a028b..68181d714c1c5b13a48a95294c5e7cd9384f1b7c 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/range_size_hash_equal_allocator.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/range_size_hash_equal_allocator.pass.cpp
@@ -32,7 +32,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string,
@@ -217,4 +217,6 @@ int main()
         assert(c.get_allocator() == A{});
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/size.fail.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/size.fail.cpp
index 284618117bcafb3c3310714522fd26b2dd16ee16..122e3aec33fbd0e11f3d2819ff3e506481f3014d 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/size.fail.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/size.fail.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<NotConstructible, NotConstructible,
@@ -66,4 +66,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/size.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/size.pass.cpp
index 3c8c46bab80b7ab162cf34949590439a8e30906c..9b58de89d9fae1e7e45b3db15450908180ea3c0f 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/size.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/size.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<NotConstructible, NotConstructible,
@@ -66,4 +66,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/size_hash.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/size_hash.pass.cpp
index b299639ee0d73086df83b8239f50c5d5096466f7..8dceccf59140631c54a88c5790422263b42eca7e 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/size_hash.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/size_hash.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<NotConstructible, NotConstructible,
@@ -70,4 +70,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/size_hash_equal.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/size_hash_equal.pass.cpp
index 2507e5e8fa49571eaf6031ab09f9f35e72f3a1c9..5d32ec29bab4f4840bc17d9ef9bb1fd42ea9b7aa 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/size_hash_equal.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/size_hash_equal.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<NotConstructible, NotConstructible,
@@ -72,4 +72,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/size_hash_equal_allocator.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/size_hash_equal_allocator.pass.cpp
index d9c6a60dfe86ad607fe7344cb858d47f287db79b..254d89d99b5aea26068c07aa173d6d092972799f 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/size_hash_equal_allocator.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.cnstr/size_hash_equal_allocator.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<NotConstructible, NotConstructible,
@@ -96,4 +96,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/clear.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/clear.pass.cpp
index 2db684a52ee4fa0296f76bc590e77a990c156031..71c3c57c215fecb21a0f14e88ebb3d6f907c1abd 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/clear.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/clear.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string> C;
@@ -60,4 +60,6 @@ int main()
         assert(c.size() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/emplace.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/emplace.pass.cpp
index aa38084df8267fc6a390a235d484985a81715e3a..1a20fb876daa0906c39407b6fb6084f8743bc6ae 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/emplace.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/emplace.pass.cpp
@@ -23,7 +23,7 @@
 #include "../../../Emplaceable.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, Emplaceable> C;
@@ -68,4 +68,6 @@ int main()
         assert(r->first == 5);
         assert(r->second == Emplaceable(6, 7));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/emplace_hint.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/emplace_hint.pass.cpp
index 3729b9e5f72d6d05ea3dfff324a7e8ddb7e32696..ef2904f3658467366a237c0ae46a53ae1649a4c0 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/emplace_hint.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/emplace_hint.pass.cpp
@@ -25,7 +25,7 @@
 #include "min_allocator.h"
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, Emplaceable> C;
@@ -88,4 +88,6 @@ int main()
         assert(r->first == 3);
         LIBCPP_ASSERT(r->second == Emplaceable(5, 6));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_const_iter.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_const_iter.pass.cpp
index 0444252566c7c8c3adc475445ccbb3fc0064d78a..5ab975077d88dfecae19db559b6c451922ec58fa 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_const_iter.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_const_iter.pass.cpp
@@ -30,7 +30,7 @@ struct TemplateConstructor
 bool operator==(const TemplateConstructor&, const TemplateConstructor&) { return false; }
 struct Hash { size_t operator() (const TemplateConstructor &) const { return 0; } };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string> C;
@@ -143,4 +143,6 @@ int main()
             m.erase(it);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_iter_db1.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_iter_db1.pass.cpp
index 4986848cd2edd056904da0b3e69c9f88b960f837..30fae95f7595f868d536485ad293ea6ebb6a4601 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_iter_db1.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_iter_db1.pass.cpp
@@ -17,7 +17,7 @@
 #include <unordered_map>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<int, int> P;
@@ -31,8 +31,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_iter_db2.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_iter_db2.pass.cpp
index 035a796e90d06e2ed82a6bd1bf0db7abb789eb61..3c0418497b0b7cbd58528a7a0da4ed1f52d69581 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_iter_db2.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_iter_db2.pass.cpp
@@ -19,7 +19,7 @@
 #include <cstdlib>
 #include <exception>
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<int, int> P;
@@ -34,8 +34,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_iter_iter_db1.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_iter_iter_db1.pass.cpp
index 8f38b65efc0483ec39b85a323f17c67023ec6753..6c3a2cf38556f95eb27135cfe9c25d12e952d121 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_iter_iter_db1.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_iter_iter_db1.pass.cpp
@@ -19,7 +19,7 @@
 #include <exception>
 #include <cstdlib>
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<int, int> P;
@@ -33,8 +33,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_iter_iter_db2.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_iter_iter_db2.pass.cpp
index 7d6a7794aa944366e1192d660c9c00dfcdac5e2b..6b0ea3528c741528e042df2ef355314e77a4ece4 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_iter_iter_db2.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_iter_iter_db2.pass.cpp
@@ -19,7 +19,7 @@
 #include <exception>
 #include <cstdlib>
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<int, int> P;
@@ -33,8 +33,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_iter_iter_db3.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_iter_iter_db3.pass.cpp
index 2502f123d95cf876def74de45bedbdfb784ab81a..0b53c1cdf08f96cd7ac689ef93f7129ad95b787f 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_iter_iter_db3.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_iter_iter_db3.pass.cpp
@@ -19,7 +19,7 @@
 #include <exception>
 #include <cstdlib>
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<int, int> P;
@@ -33,8 +33,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_iter_iter_db4.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_iter_iter_db4.pass.cpp
index a098f2a6698bd77da15fe198a3a9ee7c4e41e550..7cea5e78938b0f5e46ffd0baa225d328f0181087 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_iter_iter_db4.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_iter_iter_db4.pass.cpp
@@ -19,7 +19,7 @@
 #include <exception>
 #include <cstdlib>
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<int, int> P;
@@ -32,8 +32,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_key.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_key.pass.cpp
index 7a94e3489bf8a61a333fdab8aa448ebd957276eb..5e19c970a42ced2e09e88deba985f532e644c441 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_key.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_key.pass.cpp
@@ -37,7 +37,7 @@ bool only_deletions ( const Unordered &whole, const Unordered &part ) {
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string> C;
@@ -385,4 +385,6 @@ int main()
     assert (only_deletions (m, m2));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_range.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_range.pass.cpp
index 46ca4b40d5a5748402ff696a7446e6fcbb7657a6..50f058422b9309f5d80be77c97b35cd03a7ddff3 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_range.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/erase_range.pass.cpp
@@ -21,7 +21,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string> C;
@@ -176,4 +176,6 @@ int main()
         assert(k == c.end());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/extract_iterator.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/extract_iterator.pass.cpp
index b3ecc3556199c6d799f48500516efeaa2e740d8d..a06aca77432c7dee3704dd4f65b4137cbff4c83f 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/extract_iterator.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/extract_iterator.pass.cpp
@@ -40,7 +40,7 @@ void test(Container& c)
     assert(c.size() == 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
         using map_type = std::unordered_multimap<int, int>;
@@ -63,4 +63,6 @@ int main()
         min_alloc_map m = {{1, 1}, {2, 2}, {3, 3}, {4, 4}, {5, 5}, {6, 6}};
         test(m);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/extract_key.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/extract_key.pass.cpp
index fb27c14344715ef8d1e378dfae8d54e048f11cf5..272d5acfb76ab741287022cebe78cf4bcf09cf67 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/extract_key.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/extract_key.pass.cpp
@@ -45,7 +45,7 @@ void test(Container& c, KeyTypeIter first, KeyTypeIter last)
     }
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::unordered_multimap<int, int> m =
@@ -73,4 +73,6 @@ int main()
         int keys[] = {1, 2, 3, 4, 5, 6};
         test(m, std::begin(keys), std::end(keys));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_allocator_requirements.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_allocator_requirements.pass.cpp
index 855b5ea61115042fe426d32c31b02b7dda264cc0..73fe6b49b79c848247189e390f870ec2bad18440 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_allocator_requirements.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_allocator_requirements.pass.cpp
@@ -19,8 +19,10 @@
 #include "container_test_types.h"
 #include "../../../map_allocator_requirement_test_templates.h"
 
-int main()
+int main(int, char**)
 {
   testMultimapInsert<TCT::unordered_multimap<> >();
   testMultimapInsertHint<TCT::unordered_multimap<> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_const_lvalue.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_const_lvalue.pass.cpp
index 112af3ca4113b22e52934784bcf4f59efad46f30..8eaa69509495da85f65c99168bd382e98c38e879 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_const_lvalue.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_const_lvalue.pass.cpp
@@ -51,7 +51,7 @@ void do_insert_const_lvalue_test()
     assert(r->second == 4);
 }
 
-int main()
+int main(int, char**)
 {
     do_insert_const_lvalue_test<std::unordered_multimap<double, int> >();
 #if TEST_STD_VER >= 11
@@ -61,4 +61,6 @@ int main()
         do_insert_const_lvalue_test<C>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_hint_const_lvalue.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_hint_const_lvalue.pass.cpp
index b21adc888c13485149ff0f80a632d3bf880b4af2..83cf7b86acb3dc202f43a78701925dc688d004c3 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_hint_const_lvalue.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_hint_const_lvalue.pass.cpp
@@ -56,7 +56,7 @@ void do_insert_const_lvalue_test()
     assert(r->second == 4);
 }
 
-int main()
+int main(int, char**)
 {
     do_insert_const_lvalue_test<std::unordered_multimap<double, int> >();
 #if TEST_STD_VER >= 11
@@ -79,4 +79,6 @@ int main()
         assert(false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_hint_rvalue.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_hint_rvalue.pass.cpp
index 1485e2a8392b030f36cf06b7f6f795639233509a..2993fe7572aeba8782acbc7a77e79425208c0f3d 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_hint_rvalue.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_hint_rvalue.pass.cpp
@@ -28,7 +28,7 @@
 #include "MoveOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<double, int> C;
@@ -173,4 +173,6 @@ int main()
         assert(false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_init.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_init.pass.cpp
index a707f77c59ff6f20443f8a5e648f13234e805e4b..3a3f98785f25e44555879f26a942cc81a07417f9 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_init.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_init.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_iterators.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string> C;
@@ -117,4 +117,6 @@ int main()
         assert(static_cast<std::size_t>(std::distance(c.begin(), c.end())) == c.size());
         assert(static_cast<std::size_t>(std::distance(c.cbegin(), c.cend())) == c.size());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_node_type.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_node_type.pass.cpp
index bbaf6aac0d84bdd20ced3ab32bcf92d2da959db9..fd1cfa114cc007d8f3cd7acb00ce7b068a76e116 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_node_type.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_node_type.pass.cpp
@@ -67,10 +67,12 @@ void test(Container& c)
     }
 }
 
-int main()
+int main(int, char**)
 {
     std::unordered_multimap<int, int> m;
     test(m);
     std::unordered_multimap<int, int, std::hash<int>, std::equal_to<int>, min_allocator<std::pair<const int, int>>> m2;
     test(m2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_node_type_hint.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_node_type_hint.pass.cpp
index ae36abb922943e0120454550f35e766c21e97672..70d207551a20429c8956c17e487269cd5410b6e6 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_node_type_hint.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_node_type_hint.pass.cpp
@@ -53,10 +53,12 @@ void test(Container& c)
     }
 }
 
-int main()
+int main(int, char**)
 {
     std::unordered_multimap<int, int> m;
     test(m);
     std::unordered_multimap<int, int, std::hash<int>, std::equal_to<int>, min_allocator<std::pair<const int, int>>> m2;
     test(m2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_range.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_range.pass.cpp
index 4d0f37dbb86dac9cdd6cc08d563a50dd59166db1..333392af9020e5fc0ac7cb6c2b28adb5b1b740d6 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_range.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_range.pass.cpp
@@ -23,7 +23,7 @@
 #include "test_iterators.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<int, std::string> C;
@@ -118,4 +118,6 @@ int main()
         assert(static_cast<std::size_t>(std::distance(c.cbegin(), c.cend())) == c.size());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_rvalue.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_rvalue.pass.cpp
index 58bb723797c88fea7f2c306b515919fca0017f8f..92b91b07c318418458b6e8962f1fe4b688455f76 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_rvalue.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/insert_rvalue.pass.cpp
@@ -24,7 +24,7 @@
 #include "MoveOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multimap<double, int> C;
@@ -152,4 +152,6 @@ int main()
         assert(r->first == 5.5);
         assert(r->second == 4);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/merge.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/merge.pass.cpp
index 0f590972f37e4fde7643e92d9b391f12841ed3bb..1ce1c8361eee8b363d6fa866a69bcc6bd274de25 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/merge.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.modifiers/merge.pass.cpp
@@ -49,7 +49,7 @@ struct throw_hasher
 };
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         std::unordered_multimap<int, int> src{{1, 0}, {3, 0}, {5, 0}};
@@ -153,4 +153,5 @@ int main()
             first.merge(std::move(second));
         }
     }
+    return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.swap/db_swap_1.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.swap/db_swap_1.pass.cpp
index 8b0b8a4989e25d34a8cc5e12eb54a6eb26f84208..3e15211d5010145fa96157cc9456fe7ba90daba8 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.swap/db_swap_1.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.swap/db_swap_1.pass.cpp
@@ -21,7 +21,7 @@
 #include <unordered_map>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
 #if _LIBCPP_DEBUG >= 1
     {
@@ -40,4 +40,6 @@ int main()
         assert(false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.swap/swap_noexcept.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.swap/swap_noexcept.pass.cpp
index 6162cb2ff3b02c7533a77915cf93cebfbf5f2ec3..971fff7930eacaa97a6b7aa6d9dd5de2c890bba7 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.swap/swap_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.swap/swap_noexcept.pass.cpp
@@ -118,7 +118,7 @@ struct some_alloc3
     typedef std::false_type is_always_equal;
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::pair<const MoveOnly, MoveOnly> V;
     {
@@ -187,4 +187,6 @@ int main()
     }
 #endif // _LIBCPP_VERSION
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.swap/swap_non_member.pass.cpp b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.swap/swap_non_member.pass.cpp
index 7b639ef55996e1949fe898624256834513afce3f..406978241d114108f43716208ab9a92c204890fc 100644
--- a/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.swap/swap_non_member.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multimap/unord.multimap.swap/swap_non_member.pass.cpp
@@ -25,7 +25,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef test_hash<std::hash<int> > Hash;
@@ -579,4 +579,6 @@ int main()
         assert(c2.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/allocator_mismatch.fail.cpp b/libcxx/test/std/containers/unord/unord.multiset/allocator_mismatch.fail.cpp
index 1ff880b4e8aadabe1a8ed6245e300bdefd03cfde..6183761a32ce5371a7c62f40de05d1623a6c1bb8 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/allocator_mismatch.fail.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/allocator_mismatch.fail.cpp
@@ -11,7 +11,9 @@
 
 #include <unordered_set>
 
-int main()
+int main(int, char**)
 {
     std::unordered_multiset<int, std::hash<int>, std::less<int>, std::allocator<long> > v;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/bucket.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/bucket.pass.cpp
index a0837f9fd8657b73e05cf958df3841586829a4a3..4aeb849332016c8a5da2f08175daed2bee8888c6 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/bucket.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/bucket.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int> C;
@@ -73,4 +73,6 @@ int main()
         assert(false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/bucket_count.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/bucket_count.pass.cpp
index b6f7349612fde6e883ab27404c8d63942b293da0..8f389ebc206ba2eea525666f613907099848fe85 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/bucket_count.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/bucket_count.pass.cpp
@@ -20,7 +20,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int> C;
@@ -70,4 +70,6 @@ int main()
         assert(c.bucket_count() >= 8);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/bucket_size.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/bucket_size.pass.cpp
index 78e8c68268a422c8e40d7e7150b74803d0d66af4..99b76972aa03a0c1924a61b988abf6eed348a8ca 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/bucket_size.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/bucket_size.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int> C;
@@ -81,4 +81,6 @@ int main()
         assert(false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/clear.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/clear.pass.cpp
index 449de3520ccb25402ef034e9c0e2499a52a4032a..01ff0459383979fa9f38598f5956326fd877ffc0 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/clear.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/clear.pass.cpp
@@ -20,7 +20,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int> C;
@@ -59,4 +59,6 @@ int main()
         assert(c.size() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/count.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/count.pass.cpp
index 2eb50539b2070826546f0c43f40c612317e8929d..40cef2af203f4fcb23d8a33a93275a9fb972ea21 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/count.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/count.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int> C;
@@ -66,4 +66,6 @@ int main()
         assert(c.count(5) == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/db_iterators_7.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/db_iterators_7.pass.cpp
index 7f82cf65cb362fc308dc3e36b65d14271ca0a048..8da63023389d7c1c47c36b17fac21aaeeb7018dd 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/db_iterators_7.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/db_iterators_7.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int T;
@@ -50,8 +50,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.multiset/db_iterators_8.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/db_iterators_8.pass.cpp
index 305a76f240baa681c0e4252dfb5ec68fc3d54b50..8bc1e5c168d9448e84f55cf6ac1e278bcbb053b7 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/db_iterators_8.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/db_iterators_8.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int T;
@@ -46,8 +46,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.multiset/db_local_iterators_7.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/db_local_iterators_7.pass.cpp
index e12e3cefb9596bde03daaab08ae75d93ee3a0d3b..fbf40ca6eab2559aef42b875aec1f2433d70f5d4 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/db_local_iterators_7.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/db_local_iterators_7.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int T;
@@ -49,8 +49,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.multiset/db_local_iterators_8.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/db_local_iterators_8.pass.cpp
index 51ccf32ae0a3c6470bf8ec51c55ceebfbc6d0961..53c9c9bd58bf28062b15ed74b14622cc10a9e449 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/db_local_iterators_8.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/db_local_iterators_8.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int T;
@@ -46,8 +46,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.multiset/emplace.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/emplace.pass.cpp
index efbaa35aaa4debe59314124998c68496aec40652..67c5d1642066ff12aef28e60e8f59654bce673c2 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/emplace.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/emplace.pass.cpp
@@ -23,7 +23,7 @@
 #include "../../Emplaceable.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<Emplaceable> C;
@@ -58,4 +58,6 @@ int main()
         assert(c.size() == 3);
         assert(*r == Emplaceable(5, 6));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/emplace_hint.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/emplace_hint.pass.cpp
index 715b77425bda6178e1aff79aa75963e779cda816..61f06edd485b4cefae28dd950904893978566557 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/emplace_hint.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/emplace_hint.pass.cpp
@@ -24,7 +24,7 @@
 #include "../../Emplaceable.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<Emplaceable> C;
@@ -61,4 +61,6 @@ int main()
         assert(c.size() == 3);
         assert(*r == Emplaceable(5, 6));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/empty.fail.cpp b/libcxx/test/std/containers/unord/unord.multiset/empty.fail.cpp
index 1aeffd599f1d5e65b229ef292c9eecdbf379f12a..449b2116a547cc410854a525ac419faa038887a3 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/empty.fail.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/empty.fail.cpp
@@ -20,8 +20,10 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     std::unordered_multiset<int> c;
     c.empty();  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/empty.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/empty.pass.cpp
index f96e944a3dd5190ce1a58b446431b314d98b6107..078f95f564b6812ddc6c997c6cf0b34719ff206e 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/empty.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/empty.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::unordered_multiset<int> M;
@@ -42,4 +42,6 @@ int main()
     assert(m.empty());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/eq.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/eq.pass.cpp
index 6681e05eea206db38f07b3555000653e39d4ea4a..761ad7051e7e2e0dfafb562e350ffaa7bc95304d 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/eq.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/eq.pass.cpp
@@ -23,7 +23,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int> C;
@@ -176,4 +176,6 @@ int main()
         assert(!(c1 != c2));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/equal_range_const.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/equal_range_const.pass.cpp
index 77bfb557b499274c7e6a030a6b2b776dec802aad..ddfd77e18c6cfbe07c4027d10a2db9af41be3d1e 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/equal_range_const.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/equal_range_const.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int> C;
@@ -86,4 +86,6 @@ int main()
         assert(*r.first == 50);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/equal_range_non_const.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/equal_range_non_const.pass.cpp
index c3da35a48e710e8192543eae884e7c7570919497..a148f65b173d1bc84f8212ee09ab6bb90bcfe5a3 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/equal_range_non_const.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/equal_range_non_const.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int> C;
@@ -86,4 +86,6 @@ int main()
         assert(*r.first == 50);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/erase_const_iter.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/erase_const_iter.pass.cpp
index daa39956a6d01128f4f21dae8b989627c53c029a..0a92f7d06210dcce45ad2bd7094f21f4184820bb 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/erase_const_iter.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/erase_const_iter.pass.cpp
@@ -28,7 +28,7 @@ struct TemplateConstructor
 bool operator==(const TemplateConstructor&, const TemplateConstructor&) { return false; }
 struct Hash { size_t operator() (const TemplateConstructor &) const { return 0; } };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int> C;
@@ -96,4 +96,6 @@ int main()
             m.erase(it);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/erase_if.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/erase_if.pass.cpp
index 761b94e1d7d5528cd1e05b3f3dbed24aa22e2664..bd587473ce72cbfb5c70c3fcda7c194eddfe9e56 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/erase_if.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/erase_if.pass.cpp
@@ -79,7 +79,7 @@ void test()
     test0<S>({1,2,3}, False, {1,2,3});
 }
 
-int main()
+int main(int, char**)
 {
     test<std::unordered_multiset<int>>();
     test<std::unordered_multiset<int, std::hash<int>, std::equal_to<int>, min_allocator<int>>> ();
@@ -87,4 +87,6 @@ int main()
 
     test<std::unordered_multiset<long>>();
     test<std::unordered_multiset<double>>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/erase_iter_db1.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/erase_iter_db1.pass.cpp
index 742fe2bc2d4b2d2ce8150c2b9ef253fae0742617..073043f5a364b3fc7fe76a39253fb4249c64401d 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/erase_iter_db1.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/erase_iter_db1.pass.cpp
@@ -17,7 +17,7 @@
 #include <unordered_set>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
     int a1[] = {1, 2, 3};
@@ -30,8 +30,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.multiset/erase_iter_db2.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/erase_iter_db2.pass.cpp
index 9a6e09d4735b5d729e04345e68489a41b3b6b04a..28768eaf5c2b3d78aa7f858e2aa6fa0d4635ce8b 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/erase_iter_db2.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/erase_iter_db2.pass.cpp
@@ -19,7 +19,7 @@
 #include <cstdlib>
 #include <exception>
 
-int main()
+int main(int, char**)
 {
     {
     int a1[] = {1, 2, 3};
@@ -33,8 +33,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.multiset/erase_iter_iter_db1.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/erase_iter_iter_db1.pass.cpp
index dac9ac6afad69d2c595eda8caae4e213e02a7baf..0a9853d66e36c31e58baab43675c9dbedef27db4 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/erase_iter_iter_db1.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/erase_iter_iter_db1.pass.cpp
@@ -19,7 +19,7 @@
 #include <exception>
 #include <cstdlib>
 
-int main()
+int main(int, char**)
 {
     {
     int a1[] = {1, 2, 3};
@@ -32,8 +32,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.multiset/erase_iter_iter_db2.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/erase_iter_iter_db2.pass.cpp
index f2eb5277ee74145b50252810df33c71c1af58e2f..cc1ec00961a134df854acb7e4ebf4624d513186e 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/erase_iter_iter_db2.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/erase_iter_iter_db2.pass.cpp
@@ -19,7 +19,7 @@
 #include <exception>
 #include <cstdlib>
 
-int main()
+int main(int, char**)
 {
     {
     int a1[] = {1, 2, 3};
@@ -32,8 +32,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.multiset/erase_iter_iter_db3.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/erase_iter_iter_db3.pass.cpp
index a3e2d8cce10468e8846dce800644b6505bc76760..a1de8cb7c7108b362169e03ba22e6e3adb1bc283 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/erase_iter_iter_db3.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/erase_iter_iter_db3.pass.cpp
@@ -19,7 +19,7 @@
 #include <exception>
 #include <cstdlib>
 
-int main()
+int main(int, char**)
 {
     {
     int a1[] = {1, 2, 3};
@@ -32,8 +32,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.multiset/erase_iter_iter_db4.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/erase_iter_iter_db4.pass.cpp
index 41cc1f8737e8ddd9f2deef7a9354986db982b0f7..a82ecfc3cc364db624281644ea0bd8f77fd1de33 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/erase_iter_iter_db4.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/erase_iter_iter_db4.pass.cpp
@@ -19,7 +19,7 @@
 #include <exception>
 #include <cstdlib>
 
-int main()
+int main(int, char**)
 {
     {
     int a1[] = {1, 2, 3};
@@ -31,8 +31,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.multiset/erase_key.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/erase_key.pass.cpp
index 1ed8cd70490991d241ca47723c97ed1cdf81eb23..ba7248d746885da66baf360dd27b4c08d9b6f71b 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/erase_key.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/erase_key.pass.cpp
@@ -36,7 +36,7 @@ bool only_deletions ( const Unordered &whole, const Unordered &part ) {
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int> C;
@@ -172,4 +172,6 @@ int main()
     assert (only_deletions (m, m2));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/erase_range.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/erase_range.pass.cpp
index 8c1f8479a6250b38dd6f9e36b2b44ef1e20fd66f..c6bb4b597c3f5e41be1f28828571507edc621e28 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/erase_range.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/erase_range.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int> C;
@@ -91,4 +91,6 @@ int main()
         assert(k == c.end());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/extract_iterator.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/extract_iterator.pass.cpp
index e0a0f96b9ffd6ce70b0bd712eae8b28b021c0c59..01994120c8a3053853e1bc1a19e362d753ae66aa 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/extract_iterator.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/extract_iterator.pass.cpp
@@ -36,7 +36,7 @@ void test(Container& c)
     assert(c.size() == 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
         using set_type = std::unordered_multiset<int>;
@@ -56,4 +56,6 @@ int main()
         min_alloc_set m = {1, 2, 3, 4, 5, 6};
         test(m);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/extract_key.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/extract_key.pass.cpp
index 78d763ff5df9a0a5c300dabdeea9cede63e5f863..380b39f85e2f1064887414b68f2ee481ff741f2e 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/extract_key.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/extract_key.pass.cpp
@@ -43,7 +43,7 @@ void test(Container& c, KeyTypeIter first, KeyTypeIter last)
     }
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::unordered_multiset<int> m = {1, 2, 3, 4, 5, 6};
@@ -67,4 +67,6 @@ int main()
         int keys[] = {1, 2, 3, 4, 5, 6};
         test(m, std::begin(keys), std::end(keys));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/find_const.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/find_const.pass.cpp
index 8d6da19452a305b8d9ef70f5a1bf77cda2d4ba41..efa8bfc12b5291806c498ecd2f28d6d45a70296b 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/find_const.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/find_const.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int> C;
@@ -64,4 +64,6 @@ int main()
         assert(i == c.cend());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/find_non_const.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/find_non_const.pass.cpp
index 713f1ebe10a230c9aa391379013e1f40995f21f4..4eeb8ac6a80545f433bcf040d0dd7452efd25612 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/find_non_const.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/find_non_const.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int> C;
@@ -64,4 +64,6 @@ int main()
         assert(i == c.cend());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/incomplete.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/incomplete.pass.cpp
index 67fe1a9c084fc8f61b3a13b9d5125fab48544fdf..0aeb246ca437a9eed0dc96c427875e8401de6284 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/incomplete.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/incomplete.pass.cpp
@@ -32,6 +32,8 @@ struct A {
 
 inline bool operator==(A const& L, A const& R) { return &L == &R; }
 
-int main() {
+int main(int, char**) {
     A a;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/insert_const_lvalue.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/insert_const_lvalue.pass.cpp
index 90666e0c14fcf03f94f1374d0a975ec286657fb7..8200dc2fc94e71adb0941b9c507958f8155be172 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/insert_const_lvalue.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/insert_const_lvalue.pass.cpp
@@ -46,7 +46,7 @@ void do_insert_const_lvalue_test()
     assert(*r == 5.5);
 }
 
-int main()
+int main(int, char**)
 {
     do_insert_const_lvalue_test<std::unordered_multiset<double> >();
 #if TEST_STD_VER >= 11
@@ -56,4 +56,6 @@ int main()
         do_insert_const_lvalue_test<C>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/insert_emplace_allocator_requirements.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/insert_emplace_allocator_requirements.pass.cpp
index bc14294c38cba361c635027b2dbc09de229a2395..d7474f24e7c0f18dc54ba2146c86b4a9fd10de8c 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/insert_emplace_allocator_requirements.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/insert_emplace_allocator_requirements.pass.cpp
@@ -18,8 +18,10 @@
 #include "container_test_types.h"
 #include "../../set_allocator_requirement_test_templates.h"
 
-int main()
+int main(int, char**)
 {
   testMultisetInsert<TCT::unordered_multiset<> >();
   testMultisetEmplace<TCT::unordered_multiset<> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/insert_hint_const_lvalue.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/insert_hint_const_lvalue.pass.cpp
index 283368091e8fddf5f624a199e69cd1ba41fb4316..ede013ef99e43fc19ac4c5f54fefeffe4c6e09a5 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/insert_hint_const_lvalue.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/insert_hint_const_lvalue.pass.cpp
@@ -51,7 +51,7 @@ void do_insert_hint_const_lvalue_test()
     assert(*r == 5.5);
 }
 
-int main()
+int main(int, char**)
 {
     do_insert_hint_const_lvalue_test<std::unordered_multiset<double> >();
 #if TEST_STD_VER >= 11
@@ -74,4 +74,6 @@ int main()
         assert(false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/insert_hint_rvalue.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/insert_hint_rvalue.pass.cpp
index 39c04a1b66c80d08d471414cdcd331cf78f115c8..ab5302462e97c0b1ee182781c43490ab4c06d476 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/insert_hint_rvalue.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/insert_hint_rvalue.pass.cpp
@@ -21,7 +21,7 @@
 #include "MoveOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<double> C;
@@ -115,4 +115,6 @@ int main()
         assert(*r == 5);
     }
 #endif // TEST_STD_VER >= 11
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/insert_init.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/insert_init.pass.cpp
index 60d58c0d240990478b14f6b8f20638288153f07e..4467c74b4395eb23a6dab55286e2d092919956df 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/insert_init.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/insert_init.pass.cpp
@@ -22,7 +22,7 @@
 #include "test_iterators.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int> C;
@@ -65,4 +65,6 @@ int main()
         assert(c.count(3) == 1);
         assert(c.count(4) == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/insert_node_type.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/insert_node_type.pass.cpp
index 0a06fe6b922ef4115477513d807d1fd938f1b5e9..c660ab22d6be3e2bccf439c61bf888a287bbeb8b 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/insert_node_type.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/insert_node_type.pass.cpp
@@ -66,10 +66,12 @@ void test(Container& c)
     }
 }
 
-int main()
+int main(int, char**)
 {
     std::unordered_multiset<int> m;
     test(m);
     std::unordered_multiset<int, std::hash<int>, std::equal_to<int>, min_allocator<int>> m2;
     test(m2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/insert_node_type_hint.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/insert_node_type_hint.pass.cpp
index 36434680579a643196d9e35219e5a9f36c4d7527..e95dd31e39ecee7cc3eb39ac012132e84b5f82ca 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/insert_node_type_hint.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/insert_node_type_hint.pass.cpp
@@ -49,10 +49,12 @@ void test(Container& c)
     }
 }
 
-int main()
+int main(int, char**)
 {
     std::unordered_multiset<int> m;
     test(m);
     std::unordered_multiset<int, std::hash<int>, std::equal_to<int>, min_allocator<int>> m2;
     test(m2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/insert_range.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/insert_range.pass.cpp
index 2487a2d4bd1ab07643bc5f6c3d1e6325dbe5b44b..b8742f520b92292f80580d7750884d553022d98e 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/insert_range.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/insert_range.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_iterators.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int> C;
@@ -66,4 +66,6 @@ int main()
         assert(c.count(4) == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/insert_rvalue.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/insert_rvalue.pass.cpp
index 056288c78c1350faee0639ad6139c9312e2b0e1d..1bec2b7e6c2e90949e7ed43b7d243e32ab95ad9c 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/insert_rvalue.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/insert_rvalue.pass.cpp
@@ -21,7 +21,7 @@
 #include "MoveOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<double> C;
@@ -111,4 +111,6 @@ int main()
         assert(*r == 5);
     }
 #endif  // TEST_STD_VER >= 11
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/iterators.fail.cpp b/libcxx/test/std/containers/unord/unord.multiset/iterators.fail.cpp
index 3cf31d52c0169a528826015e67946512d90550c0..2c282fdbaab4bfb67b9c2be0d931e09aea038977 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/iterators.fail.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/iterators.fail.cpp
@@ -24,7 +24,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int> C;
@@ -65,4 +65,6 @@ int main()
         assert(std::distance(c.begin(), c.end()) == c.size());
         assert(std::distance(c.cbegin(), c.cend()) == c.size());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/iterators.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/iterators.pass.cpp
index b6147e9c64daa4161f824c43817ad8a73d304153..2c0cd496ddb240c1b6b3de17d411b5c35df22623 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/iterators.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/iterators.pass.cpp
@@ -26,7 +26,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int> C;
@@ -125,4 +125,6 @@ int main()
         assert (!(cii != ii1 ));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/load_factor.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/load_factor.pass.cpp
index ece450ceb170693c8b05081df40ba2c403cd7524..bb3350e8689884002427a84e718e403fb0068a3e 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/load_factor.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/load_factor.pass.cpp
@@ -21,7 +21,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int> C;
@@ -71,4 +71,6 @@ int main()
         assert(c.load_factor() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/local_iterators.fail.cpp b/libcxx/test/std/containers/unord/unord.multiset/local_iterators.fail.cpp
index a27353414a62c2dc0320fd9dea0e15c7cd2582e2..d6f1a55fd49cbc41d2aa0d703a8a75fd18096c4e 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/local_iterators.fail.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/local_iterators.fail.cpp
@@ -24,7 +24,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int> C;
@@ -259,4 +259,6 @@ int main()
         j = c.cend(b);
         assert(std::distance(i, j) == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/local_iterators.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/local_iterators.pass.cpp
index b63a94ae10093c22920f4a6649ddeafbdf732fcb..5aa65756371c806089a986dfafa11eb66c2a5619 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/local_iterators.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/local_iterators.pass.cpp
@@ -24,7 +24,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int> C;
@@ -496,4 +496,6 @@ int main()
         assert(std::distance(i, j) == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/max_bucket_count.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/max_bucket_count.pass.cpp
index c503a35378e3a63c8c7e4034665367ea30757f6c..7fb76c41c492ad1693f16ffcd695d3bf068eacbd 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/max_bucket_count.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/max_bucket_count.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int> C;
@@ -34,4 +34,6 @@ int main()
         assert(c.max_bucket_count() > 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/max_load_factor.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/max_load_factor.pass.cpp
index 1a6b1335a62ec4a078c14d99163e5a2863f18538..c89aa6d339f134c1a9c6f9f33cc624fe7ad4068c 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/max_load_factor.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/max_load_factor.pass.cpp
@@ -24,7 +24,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int> C;
@@ -62,4 +62,6 @@ int main()
         assert(false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/max_size.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/max_size.pass.cpp
index a6a7dae25195f8b3d3ed7c4b19c80f829580cedb..d08cdb6221fd3cffa1d7732a260cd9079062d8ae 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/max_size.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/max_size.pass.cpp
@@ -20,7 +20,7 @@
 #include "test_allocator.h"
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
       typedef limited_allocator<int, 10> A;
@@ -50,4 +50,6 @@ int main()
       assert(c.max_size() <= max_dist);
       assert(c.max_size() <= alloc_max_size(c.get_allocator()));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/merge.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/merge.pass.cpp
index 1082f4990f89c071efd85e1a43d50dca68bf73fe..e951b33d2127bbc765b4adb22c1c496c4ac9c505 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/merge.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/merge.pass.cpp
@@ -49,7 +49,7 @@ struct throw_hasher
 };
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         std::unordered_multiset<int> src{1, 3, 5};
@@ -150,4 +150,5 @@ int main()
             first.merge(std::move(second));
         }
     }
+    return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/rehash.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/rehash.pass.cpp
index 38691f20040dcbf24b30bf4e41dda8505c1c1546..8c6699b18e247382ed9920524c82824ecca14b27 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/rehash.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/rehash.pass.cpp
@@ -36,7 +36,7 @@ void test(const C& c)
     assert(c.count(4) == 1);
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int> C;
@@ -99,4 +99,6 @@ int main()
         test(c);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/reserve.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/reserve.pass.cpp
index 079786689f6f3d37e1569b29e1a88f8bf4a8438d..54eada5a76989101e13b64e4b258e30630f92783 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/reserve.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/reserve.pass.cpp
@@ -45,7 +45,7 @@ void reserve_invariant(size_t n) // LWG #2156
     }
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int> C;
@@ -103,4 +103,6 @@ int main()
     }
 #endif
     reserve_invariant(20);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/scary.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/scary.pass.cpp
index 7ef4a513f6423ce330bdde66466690cab9d4bc39..670c6406a2bd618366a1bf7e3ebaa83c93c5865f 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/scary.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/scary.pass.cpp
@@ -14,11 +14,13 @@
 
 #include <unordered_set>
 
-int main()
+int main(int, char**)
 {
     typedef std::unordered_set<int> M1;
     typedef std::unordered_multiset<int> M2;
     M2::iterator i;
     M1::iterator j = i;
     ((void)j);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/size.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/size.pass.cpp
index 3aae7dd53c2381c8fd9a7daccd7d96adc01876f4..12a4733ccb192294f96b69858863520b27aa7b1e 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/size.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/size.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::unordered_multiset<int> M;
@@ -58,4 +58,6 @@ int main()
     assert(m.size() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/swap_member.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/swap_member.pass.cpp
index 2937e444e4a8d23af60c9882940158956ba265a7..bad8df9d9f09c7e8150c75a58de4a82c87c658dd 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/swap_member.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/swap_member.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef test_hash<std::hash<int> > Hash;
@@ -566,4 +566,6 @@ int main()
         assert(c2.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/types.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/types.pass.cpp
index 8b246778d4978bac456e3172170ae2ee3d00dcd2..81f8334c28f1177f024453613bec4ceb1db8ff0c 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/types.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/types.pass.cpp
@@ -31,7 +31,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<short> C;
@@ -65,4 +65,6 @@ int main()
         static_assert((std::is_same<C::difference_type, std::ptrdiff_t>::value), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/allocator.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/allocator.pass.cpp
index e446fa65e32fad66444f8dc237d36d2bd65817b9..2a3b867b5e0aa8a100f50e215ef0aed7fc132999 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/allocator.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/allocator.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<NotConstructible,
@@ -106,4 +106,6 @@ int main()
     }
 #endif
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/assign_copy.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/assign_copy.pass.cpp
index c90a0106af8727db7f13aff88a1f95db6cd10159..1fcd71002e9558916ea046615b03eb447bf8ee3d 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/assign_copy.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/assign_copy.pass.cpp
@@ -27,7 +27,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef test_allocator<int> A;
@@ -209,4 +209,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/assign_init.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/assign_init.pass.cpp
index cf286319d42b340c99ddaeb3e31900cc2399a0f7..795370c44fe8b3bea737a83ad713de8c8348e8bb 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/assign_init.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/assign_init.pass.cpp
@@ -27,7 +27,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef test_allocator<int> A;
@@ -93,4 +93,6 @@ int main()
         assert(fabs(c.load_factor() - (float)c.size()/c.bucket_count()) < FLT_EPSILON);
         assert(c.max_load_factor() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/assign_move.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/assign_move.pass.cpp
index 00adca3c4525cfd9a5397e1ce5e31d015cc69c7f..1ed77851cf3f2a1869222e5f2769eb67a55f3512 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/assign_move.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/assign_move.pass.cpp
@@ -28,7 +28,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef test_allocator<int> A;
@@ -263,4 +263,6 @@ int main()
         assert(fabs(c.load_factor() - (float)c.size()/c.bucket_count()) < FLT_EPSILON);
         assert(c.max_load_factor() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/compare_copy_constructible.fail.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/compare_copy_constructible.fail.cpp
index b1e161b42e02391bfd0eeb044f426285b6fb8b1e..4b8d55cac982b44cb4b860483677d7303d27c8f1 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/compare_copy_constructible.fail.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/compare_copy_constructible.fail.cpp
@@ -23,6 +23,8 @@ private:
     };
 
 
-int main() {
+int main(int, char**) {
     std::unordered_multiset<int, std::hash<int>, Comp<int> > m;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/copy.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/copy.pass.cpp
index e3a57fa55549f27fcd48f4ef895c38ee32b219d1..f3ca15241ad9dc7e3fb6d46bb67ba979e8073f22 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/copy.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/copy.pass.cpp
@@ -26,7 +26,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int,
@@ -168,4 +168,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/copy_alloc.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/copy_alloc.pass.cpp
index aac5fde6a79627f54de9a7f4c8e36ff4d7b8d9df..4e99490ea6111bb28e41548d7b5cb3973ed1dc44 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/copy_alloc.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/copy_alloc.pass.cpp
@@ -26,7 +26,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int,
@@ -122,4 +122,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/default.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/default.pass.cpp
index 85fc84896b8a4ad7dcfefc5e56bd723785e54dc7..bb762b576caa6cb5eb5b6c38006a2462eaa00c3f 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/default.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/default.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<NotConstructible,
@@ -104,4 +104,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/default_noexcept.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/default_noexcept.pass.cpp
index 71661d5ea157c85c919310c1d82dabd5a37ddc0b..4acda32557d008205e0aec580833b75a0cac50a1 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/default_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/default_noexcept.pass.cpp
@@ -44,7 +44,7 @@ struct some_hash
     std::size_t operator()(T const&) const;
 };
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -71,4 +71,6 @@ int main()
                                                          some_comp<MoveOnly>> C;
         static_assert(!std::is_nothrow_default_constructible<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/dtor_noexcept.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/dtor_noexcept.pass.cpp
index c65c0f15e10fe79507f5207f99513ec395d177e8..1d963b6be7b785c79d862501f2ee4727bc0baefb 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/dtor_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/dtor_noexcept.pass.cpp
@@ -37,7 +37,7 @@ struct some_hash
     std::size_t operator()(T const&) const;
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<MoveOnly> C;
@@ -64,4 +64,6 @@ int main()
         static_assert(!std::is_nothrow_destructible<C>::value, "");
     }
 #endif // _LIBCPP_VERSION
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/hash_copy_constructible.fail.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/hash_copy_constructible.fail.cpp
index 97b031ab81ab811319010a8aa1ab0410f71de6a2..9e24ce2ecbcde7354917cbd63d3a47f597c4de7d 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/hash_copy_constructible.fail.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/hash_copy_constructible.fail.cpp
@@ -23,6 +23,8 @@ private:
     };
 
 
-int main() {
+int main(int, char**) {
     std::unordered_multiset<int, Hash<int> > m;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/init.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/init.pass.cpp
index 7b3d996f7880f274a36b06f4fea6b4bfb43299be..d8fc0c0021c758b8d22c1630e5cf48bc30d65181 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/init.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/init.pass.cpp
@@ -28,7 +28,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int,
@@ -160,4 +160,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif // TEST_STD_VER > 11
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/init_size.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/init_size.pass.cpp
index 475f2664da0e9b741970bde895b24aa0645de782..bda874ce559252ca2bde5a6193f55cc1bb759c41 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/init_size.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/init_size.pass.cpp
@@ -28,7 +28,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int,
@@ -94,4 +94,6 @@ int main()
         assert(std::fabs(c.load_factor() - (float)c.size()/c.bucket_count()) < FLT_EPSILON);
         assert(c.max_load_factor() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/init_size_hash.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/init_size_hash.pass.cpp
index de5f6ae174d1c1ac3e47064274a5d009453a4884..5c81a3461e18f91a05d970a178e07fddf0e90200 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/init_size_hash.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/init_size_hash.pass.cpp
@@ -29,7 +29,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int,
@@ -97,4 +97,6 @@ int main()
         assert(std::fabs(c.load_factor() - (float)c.size()/c.bucket_count()) < FLT_EPSILON);
         assert(c.max_load_factor() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/init_size_hash_equal.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/init_size_hash_equal.pass.cpp
index cffd9d55eb1f61d3479fd4592ee9294c1d4be549..c77d85057aee6bce37f38f49a78b6f986d992d7d 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/init_size_hash_equal.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/init_size_hash_equal.pass.cpp
@@ -29,7 +29,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int,
@@ -99,4 +99,6 @@ int main()
         assert(std::fabs(c.load_factor() - (float)c.size()/c.bucket_count()) < FLT_EPSILON);
         assert(c.max_load_factor() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/init_size_hash_equal_allocator.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/init_size_hash_equal_allocator.pass.cpp
index 57df301452006e7d8aea19dafd4e83eb494127a5..8a26b3948ec9424e53d5c40216970f036a558e14 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/init_size_hash_equal_allocator.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/init_size_hash_equal_allocator.pass.cpp
@@ -29,7 +29,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int,
@@ -101,4 +101,6 @@ int main()
         assert(std::fabs(c.load_factor() - (float)c.size()/c.bucket_count()) < FLT_EPSILON);
         assert(c.max_load_factor() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/move.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/move.pass.cpp
index 670102be4193f9cf31542ba937a395d16a1735ca..196044f21c662786b61f40f5de042cbd4e109546 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/move.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/move.pass.cpp
@@ -28,7 +28,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int,
@@ -171,4 +171,6 @@ int main()
         assert(s2.size() == 2);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/move_alloc.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/move_alloc.pass.cpp
index 5e822b4587f741c80b0ae45b75ae1711ddbf941b..eb567a9da7533e08d572a7e760810b4d4b260810 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/move_alloc.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/move_alloc.pass.cpp
@@ -28,7 +28,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int P;
@@ -202,4 +202,6 @@ int main()
 
         assert(c0.empty());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/move_assign_noexcept.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/move_assign_noexcept.pass.cpp
index 702125b661e0e2fd26eb8069cb2bf2c12ac0392e..4b0051a9be5360b08476a19dc0d8887a8be037ba 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/move_assign_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/move_assign_noexcept.pass.cpp
@@ -43,7 +43,7 @@ struct some_hash
     std::size_t operator()(T const&) const;
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<MoveOnly> C;
@@ -70,4 +70,6 @@ int main()
                                                          some_comp<MoveOnly>> C;
         static_assert(!std::is_nothrow_move_assignable<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/move_noexcept.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/move_noexcept.pass.cpp
index 03f61a504d3c4a9edd649d74027983e24d481366..3941940f9a0a0d3e55224aec0498727b57ee2290 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/move_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/move_noexcept.pass.cpp
@@ -40,7 +40,7 @@ struct some_hash
     std::size_t operator()(T const&) const;
 };
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -67,4 +67,6 @@ int main()
                                                          some_comp<MoveOnly>> C;
         static_assert(!std::is_nothrow_move_constructible<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/range.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/range.pass.cpp
index 5d729ec49653c4c92229f5c9a0d7c0a7bbed01c3..953e702a682456c84cea669319c4dd3b0d51d2bb 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/range.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/range.pass.cpp
@@ -28,7 +28,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int,
@@ -166,4 +166,6 @@ int main()
     }
 #endif
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/range_size.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/range_size.pass.cpp
index d423c8864880af8f20b7f96f6bb51c31d47ae0c7..2b7e911cd8f39c2e622d098b7a123fcae37967ea 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/range_size.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/range_size.pass.cpp
@@ -28,7 +28,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int,
@@ -100,4 +100,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/range_size_hash.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/range_size_hash.pass.cpp
index 84f7d5a1310f29a85fda14991b646c760b489b7d..1b394413041c59ddda7d8ae91946a7488fde8e9e 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/range_size_hash.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/range_size_hash.pass.cpp
@@ -29,7 +29,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int,
@@ -103,4 +103,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/range_size_hash_equal.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/range_size_hash_equal.pass.cpp
index 93d92257cb01f1f5706fc97b9d1d1c0db54e91c8..d83555f57e6f7d8b84b433fc667ad097ca8fc173 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/range_size_hash_equal.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/range_size_hash_equal.pass.cpp
@@ -29,7 +29,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int,
@@ -105,4 +105,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/range_size_hash_equal_allocator.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/range_size_hash_equal_allocator.pass.cpp
index e8e425f2df7379e2e5fedfc15714512454a961e8..10c69c27ab8b6fc9ea15e375a41c02bef561c0ff 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/range_size_hash_equal_allocator.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/range_size_hash_equal_allocator.pass.cpp
@@ -30,7 +30,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<int,
@@ -108,4 +108,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/size.fail.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/size.fail.cpp
index d115f98fe1ea7184540f6ebc943f0abe709bca81..45d67f33a61c8b0b165feb6b6079697049b192b2 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/size.fail.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/size.fail.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<NotConstructible,
@@ -62,4 +62,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/size.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/size.pass.cpp
index 2e1c749f2ceb2375e5be9061f7456a5100a6184e..ba32ec37055879519d1287bf7292392ac7b858c9 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/size.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/size.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<NotConstructible,
@@ -62,4 +62,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/size_hash.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/size_hash.pass.cpp
index 3868b372003a280cd3b459f8d10c3ac293b6ec52..47d0867f0f944a6789dfade06ea8208b8b4fe44e 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/size_hash.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/size_hash.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<NotConstructible,
@@ -66,4 +66,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/size_hash_equal.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/size_hash_equal.pass.cpp
index eebcc14a68b9de441a94a27590da32c0d61cddd9..f9cc2503b68a5c174ab3a3bad6cd7562add7aa99 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/size_hash_equal.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/size_hash_equal.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<NotConstructible,
@@ -68,4 +68,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/size_hash_equal_allocator.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/size_hash_equal_allocator.pass.cpp
index ab2ac6ee547edbc846bbaa676bd0202297ac44c5..8e25bf00e21ffd344d2cf7fa8deeb7b891518c83 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/size_hash_equal_allocator.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.cnstr/size_hash_equal_allocator.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<NotConstructible,
@@ -70,4 +70,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.swap/db_swap_1.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.swap/db_swap_1.pass.cpp
index 3ad54c42fbae9960d0b3904dfa688c998cd82f2a..a546d0d7d1de81d00f23dfa38e69b19440856135 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.swap/db_swap_1.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.swap/db_swap_1.pass.cpp
@@ -21,7 +21,7 @@
 #include <unordered_set>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
 #if _LIBCPP_DEBUG >= 1
     {
@@ -39,4 +39,6 @@ int main()
         assert(false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.swap/swap_noexcept.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.swap/swap_noexcept.pass.cpp
index 73c3cc66a0d4209d3a4a0fc5d8c88b406be9a3ff..3586e8d5bd53f7b3ffacd689787ad792ef2da286 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.swap/swap_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.swap/swap_noexcept.pass.cpp
@@ -118,7 +118,7 @@ struct some_alloc3
     typedef std::false_type is_always_equal;
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_multiset<MoveOnly> C;
@@ -186,4 +186,6 @@ int main()
     }
 #endif // _LIBCPP_VERSION
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.swap/swap_non_member.pass.cpp b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.swap/swap_non_member.pass.cpp
index 60826ffd199a7c3633bb332f919f6380d2970d23..706c995f3de5a594ad6ca17c544fafd33bac8d4a 100644
--- a/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.swap/swap_non_member.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.multiset/unord.multiset.swap/swap_non_member.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef test_hash<std::hash<int> > Hash;
@@ -566,4 +566,6 @@ int main()
         assert(c2.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/allocator_mismatch.fail.cpp b/libcxx/test/std/containers/unord/unord.set/allocator_mismatch.fail.cpp
index 6286031e590b20b363ed434864c700a9fa39b7c7..0d1341e6939cc2c6240da9e805ac56fcda934c52 100644
--- a/libcxx/test/std/containers/unord/unord.set/allocator_mismatch.fail.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/allocator_mismatch.fail.cpp
@@ -11,7 +11,9 @@
 
 #include <unordered_set>
 
-int main()
+int main(int, char**)
 {
     std::unordered_set<int, std::hash<int>, std::less<int>, std::allocator<long> > v;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/bucket.pass.cpp b/libcxx/test/std/containers/unord/unord.set/bucket.pass.cpp
index 58d77e3d57acc196cd6e92a927ec6036e1553e80..2215b99493b9a357c91783610ddeeb9ef33ac683 100644
--- a/libcxx/test/std/containers/unord/unord.set/bucket.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/bucket.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int> C;
@@ -72,4 +72,6 @@ int main()
         assert(false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/bucket_count.pass.cpp b/libcxx/test/std/containers/unord/unord.set/bucket_count.pass.cpp
index 3dadbd21a977a7f36136abdaa68d489a9b7a1cb7..3a1a78cb3d80aa85c1f4089bd29e3a4e9d504103 100644
--- a/libcxx/test/std/containers/unord/unord.set/bucket_count.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/bucket_count.pass.cpp
@@ -20,7 +20,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int> C;
@@ -68,4 +68,6 @@ int main()
         assert(c.bucket_count() >= 8);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/bucket_size.pass.cpp b/libcxx/test/std/containers/unord/unord.set/bucket_size.pass.cpp
index e37e047af66ea792bec2741cf74b2d156aa6e5ba..6ca89d57224726b37a587239ceb7143cab0cf9cc 100644
--- a/libcxx/test/std/containers/unord/unord.set/bucket_size.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/bucket_size.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int> C;
@@ -76,4 +76,6 @@ int main()
         assert(false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/clear.pass.cpp b/libcxx/test/std/containers/unord/unord.set/clear.pass.cpp
index abaaec3e258c3b224a131dac77ce9a80c6199015..ab04cdd9105993535be104f950748a786ef03c2f 100644
--- a/libcxx/test/std/containers/unord/unord.set/clear.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/clear.pass.cpp
@@ -20,7 +20,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int> C;
@@ -58,4 +58,6 @@ int main()
         assert(c.size() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/count.pass.cpp b/libcxx/test/std/containers/unord/unord.set/count.pass.cpp
index 97694684de0a7e364d6554e22049d43323e5b389..971e126fdc676c1477ede2f4e690478ec58c406c 100644
--- a/libcxx/test/std/containers/unord/unord.set/count.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/count.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int> C;
@@ -65,4 +65,6 @@ int main()
         assert(c.count(5) == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/db_iterators_7.pass.cpp b/libcxx/test/std/containers/unord/unord.set/db_iterators_7.pass.cpp
index ef58e2561330a7a3fc94f8abfe95e8823860b77b..8420de60d331be59eed87946e81e50bbb8a4fd00 100644
--- a/libcxx/test/std/containers/unord/unord.set/db_iterators_7.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/db_iterators_7.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int T;
@@ -50,8 +50,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.set/db_iterators_8.pass.cpp b/libcxx/test/std/containers/unord/unord.set/db_iterators_8.pass.cpp
index 10692fa4904f0141d88b8531d9435474b456163e..14dccf97db023a0590785804f527536946ffb637 100644
--- a/libcxx/test/std/containers/unord/unord.set/db_iterators_8.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/db_iterators_8.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int T;
@@ -46,8 +46,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.set/db_local_iterators_7.pass.cpp b/libcxx/test/std/containers/unord/unord.set/db_local_iterators_7.pass.cpp
index e3a04f6a95f2a3fe6727279aec8ff918241ae08a..ac066af7fbeae9ab64c3479d11a62c008cf857e6 100644
--- a/libcxx/test/std/containers/unord/unord.set/db_local_iterators_7.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/db_local_iterators_7.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int T;
@@ -49,8 +49,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.set/db_local_iterators_8.pass.cpp b/libcxx/test/std/containers/unord/unord.set/db_local_iterators_8.pass.cpp
index 57dfda6fc683c1a8f4c319423402f50287eb74ff..a1595cd360142972df447bca08c13c3e8c4dd1db 100644
--- a/libcxx/test/std/containers/unord/unord.set/db_local_iterators_8.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/db_local_iterators_8.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef int T;
@@ -46,8 +46,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.set/emplace.pass.cpp b/libcxx/test/std/containers/unord/unord.set/emplace.pass.cpp
index 32e6e348722fa0a52a70a05ca2bdb563a7bc819e..6616aa51c2cd8cbcf2299e931c5906f06970ef07 100644
--- a/libcxx/test/std/containers/unord/unord.set/emplace.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/emplace.pass.cpp
@@ -23,7 +23,7 @@
 #include "../../Emplaceable.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<Emplaceable> C;
@@ -64,4 +64,6 @@ int main()
         assert(*r.first == Emplaceable(5, 6));
         assert(!r.second);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/emplace_hint.pass.cpp b/libcxx/test/std/containers/unord/unord.set/emplace_hint.pass.cpp
index 1bab8d9c3291a708b270fee4d8ff2b108cfc540b..55b3ccbc97896d3a591ecf87d09089fcfaf8bd93 100644
--- a/libcxx/test/std/containers/unord/unord.set/emplace_hint.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/emplace_hint.pass.cpp
@@ -24,7 +24,7 @@
 #include "../../Emplaceable.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<Emplaceable> C;
@@ -61,4 +61,6 @@ int main()
         assert(c.size() == 2);
         assert(*r == Emplaceable(5, 6));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/empty.fail.cpp b/libcxx/test/std/containers/unord/unord.set/empty.fail.cpp
index f683f23a7f341be29599f88457b8b0f8b9dca99f..11273f44fceb12fa53454f23d576ba2a1f5952c4 100644
--- a/libcxx/test/std/containers/unord/unord.set/empty.fail.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/empty.fail.cpp
@@ -20,8 +20,10 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     std::unordered_set<int> c;
     c.empty();  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/empty.pass.cpp b/libcxx/test/std/containers/unord/unord.set/empty.pass.cpp
index 3656e60c0eda565d698d3bbeb270559ff271532e..ce9cfdcf5f479ffd8305ceacd53ab934c1b31e9e 100644
--- a/libcxx/test/std/containers/unord/unord.set/empty.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/empty.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::unordered_set<int> M;
@@ -42,4 +42,6 @@ int main()
     assert(m.empty());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/eq.pass.cpp b/libcxx/test/std/containers/unord/unord.set/eq.pass.cpp
index 82737f1ba0594b23be404a392ddb768a94309407..5362f57f4f5d25578d77e1f8a68d96d6b10d836a 100644
--- a/libcxx/test/std/containers/unord/unord.set/eq.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/eq.pass.cpp
@@ -23,7 +23,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int> C;
@@ -155,4 +155,6 @@ int main()
         assert(!(c1 != c2));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/equal_range_const.pass.cpp b/libcxx/test/std/containers/unord/unord.set/equal_range_const.pass.cpp
index 587971b743aea877b5d4231105710de9ed1939d2..9489deaf2ea4470a56f749fad20b83eae645550b 100644
--- a/libcxx/test/std/containers/unord/unord.set/equal_range_const.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/equal_range_const.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int> C;
@@ -77,4 +77,6 @@ int main()
         assert(*r.first == 50);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/equal_range_non_const.pass.cpp b/libcxx/test/std/containers/unord/unord.set/equal_range_non_const.pass.cpp
index 923c1764d94852f8356a584b5574f2e44a071285..6713dbd91e081985154734f2f409f269a07006e4 100644
--- a/libcxx/test/std/containers/unord/unord.set/equal_range_non_const.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/equal_range_non_const.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int> C;
@@ -77,4 +77,6 @@ int main()
         assert(*r.first == 50);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/erase_const_iter.pass.cpp b/libcxx/test/std/containers/unord/unord.set/erase_const_iter.pass.cpp
index 84f4f81d19a8ef1755b006e7e622fa2d2ae54146..3d9cfe6834fa9f574d8789f0aa31263b465bb09c 100644
--- a/libcxx/test/std/containers/unord/unord.set/erase_const_iter.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/erase_const_iter.pass.cpp
@@ -28,7 +28,7 @@ struct TemplateConstructor
 bool operator==(const TemplateConstructor&, const TemplateConstructor&) { return false; }
 struct Hash { size_t operator() (const TemplateConstructor &) const { return 0; } };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int> C;
@@ -94,4 +94,6 @@ int main()
             m.erase(it);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/erase_if.pass.cpp b/libcxx/test/std/containers/unord/unord.set/erase_if.pass.cpp
index 2b5f8f6c87b38fa891dcda4f23b866909f5171e1..cbd2ebb1afb307416aed8c5102bace7d5621da96 100644
--- a/libcxx/test/std/containers/unord/unord.set/erase_if.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/erase_if.pass.cpp
@@ -69,7 +69,7 @@ void test()
     test0<S>({1,2,3}, False, {1,2,3});
 }
 
-int main()
+int main(int, char**)
 {
     test<std::unordered_set<int>>();
     test<std::unordered_set<int, std::hash<int>, std::equal_to<int>, min_allocator<int>>> ();
@@ -77,4 +77,6 @@ int main()
 
     test<std::unordered_set<long>>();
     test<std::unordered_set<double>>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/erase_iter_db1.pass.cpp b/libcxx/test/std/containers/unord/unord.set/erase_iter_db1.pass.cpp
index 3bf6282ccc2e42d87bfdb1a1739f9a51cdddbe6d..a65086ee8c66a46a4a680743b69c52ea225414e0 100644
--- a/libcxx/test/std/containers/unord/unord.set/erase_iter_db1.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/erase_iter_db1.pass.cpp
@@ -17,7 +17,7 @@
 #include <unordered_set>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
     int a1[] = {1, 2, 3};
@@ -30,8 +30,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.set/erase_iter_db2.pass.cpp b/libcxx/test/std/containers/unord/unord.set/erase_iter_db2.pass.cpp
index 34f8a60766e981b67d8948e4b51a27a5225bdfb4..c7f64da355cc726145b0b112a10aba6e6b8e0bdc 100644
--- a/libcxx/test/std/containers/unord/unord.set/erase_iter_db2.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/erase_iter_db2.pass.cpp
@@ -19,7 +19,7 @@
 #include <cstdlib>
 #include <exception>
 
-int main()
+int main(int, char**)
 {
     {
     int a1[] = {1, 2, 3};
@@ -33,8 +33,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.set/erase_iter_iter_db1.pass.cpp b/libcxx/test/std/containers/unord/unord.set/erase_iter_iter_db1.pass.cpp
index bcf3df82b77fcc0f7176509e7bf10fe0e761e371..002a24bf1bc154c699eb94506ca876cc739bb46b 100644
--- a/libcxx/test/std/containers/unord/unord.set/erase_iter_iter_db1.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/erase_iter_iter_db1.pass.cpp
@@ -19,7 +19,7 @@
 #include <exception>
 #include <cstdlib>
 
-int main()
+int main(int, char**)
 {
     {
     int a1[] = {1, 2, 3};
@@ -32,8 +32,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.set/erase_iter_iter_db2.pass.cpp b/libcxx/test/std/containers/unord/unord.set/erase_iter_iter_db2.pass.cpp
index 1a222d91ba303ee0c7462d9e4f7d588d3019ed45..59bf0cc33fe6f55eea31917439e6a845acae12fc 100644
--- a/libcxx/test/std/containers/unord/unord.set/erase_iter_iter_db2.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/erase_iter_iter_db2.pass.cpp
@@ -19,7 +19,7 @@
 #include <exception>
 #include <cstdlib>
 
-int main()
+int main(int, char**)
 {
     {
     int a1[] = {1, 2, 3};
@@ -32,8 +32,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.set/erase_iter_iter_db3.pass.cpp b/libcxx/test/std/containers/unord/unord.set/erase_iter_iter_db3.pass.cpp
index 83cc5d558d57f54221767e54d658b97334f5198e..c522fce26336c8382466a34347cddb979d61f50d 100644
--- a/libcxx/test/std/containers/unord/unord.set/erase_iter_iter_db3.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/erase_iter_iter_db3.pass.cpp
@@ -19,7 +19,7 @@
 #include <exception>
 #include <cstdlib>
 
-int main()
+int main(int, char**)
 {
     {
     int a1[] = {1, 2, 3};
@@ -32,8 +32,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.set/erase_iter_iter_db4.pass.cpp b/libcxx/test/std/containers/unord/unord.set/erase_iter_iter_db4.pass.cpp
index 218d50137b63c51642d74f960065c0bf5f812386..a7c3c0020756cd5b17437a4800aee993278d34c9 100644
--- a/libcxx/test/std/containers/unord/unord.set/erase_iter_iter_db4.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/erase_iter_iter_db4.pass.cpp
@@ -19,7 +19,7 @@
 #include <exception>
 #include <cstdlib>
 
-int main()
+int main(int, char**)
 {
     {
     int a1[] = {1, 2, 3};
@@ -31,8 +31,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/containers/unord/unord.set/erase_key.pass.cpp b/libcxx/test/std/containers/unord/unord.set/erase_key.pass.cpp
index ea80e2d019ca2ba1093aa5f32edaa6a7ffef9d07..912a4ae6b15b924c78e82cdb55e4310b24dac309 100644
--- a/libcxx/test/std/containers/unord/unord.set/erase_key.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/erase_key.pass.cpp
@@ -36,7 +36,7 @@ bool only_deletions ( const Unordered &whole, const Unordered &part ) {
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int> C;
@@ -171,4 +171,6 @@ int main()
     assert (only_deletions (m, m2));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/erase_range.pass.cpp b/libcxx/test/std/containers/unord/unord.set/erase_range.pass.cpp
index 11908637bf69fbf25c2772a7616b69a00fedd791..907063c6a5a93962f83ace1ac84d6f184c96738b 100644
--- a/libcxx/test/std/containers/unord/unord.set/erase_range.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/erase_range.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int> C;
@@ -90,4 +90,6 @@ int main()
         assert(k == c.end());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/extract_iterator.pass.cpp b/libcxx/test/std/containers/unord/unord.set/extract_iterator.pass.cpp
index e03e11ff6723beab8c717a9b99f1222b1054f5b6..03dfcc6028498c4b9f2afb63608f4f48b4a6287f 100644
--- a/libcxx/test/std/containers/unord/unord.set/extract_iterator.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/extract_iterator.pass.cpp
@@ -36,7 +36,7 @@ void test(Container& c)
     assert(c.size() == 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
         using set_type = std::unordered_set<int>;
@@ -56,4 +56,6 @@ int main()
         min_alloc_set m = {1, 2, 3, 4, 5, 6};
         test(m);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/extract_key.pass.cpp b/libcxx/test/std/containers/unord/unord.set/extract_key.pass.cpp
index 9a6123714804d8bacc9fb21c0e26345c7c0d898c..b2a6f04935b14f3d3fdbf6127ef5b0cd3f31260d 100644
--- a/libcxx/test/std/containers/unord/unord.set/extract_key.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/extract_key.pass.cpp
@@ -43,7 +43,7 @@ void test(Container& c, KeyTypeIter first, KeyTypeIter last)
     }
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::unordered_set<int> m = {1, 2, 3, 4, 5, 6};
@@ -67,4 +67,6 @@ int main()
         int keys[] = {1, 2, 3, 4, 5, 6};
         test(m, std::begin(keys), std::end(keys));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/find_const.pass.cpp b/libcxx/test/std/containers/unord/unord.set/find_const.pass.cpp
index e46e3d5f1d7c2586e1fdc18ee2f331215310100e..f226a69606fd28287c123c6e56d6bdb678151f94 100644
--- a/libcxx/test/std/containers/unord/unord.set/find_const.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/find_const.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int> C;
@@ -63,4 +63,6 @@ int main()
         assert(i == c.cend());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/find_non_const.pass.cpp b/libcxx/test/std/containers/unord/unord.set/find_non_const.pass.cpp
index bbd37754eed128be53c22736fcd1815a086d7f38..4b24b2f447c353308815013ac98aa1c9085cc110 100644
--- a/libcxx/test/std/containers/unord/unord.set/find_non_const.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/find_non_const.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int> C;
@@ -63,4 +63,6 @@ int main()
         assert(i == c.cend());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/incomplete.pass.cpp b/libcxx/test/std/containers/unord/unord.set/incomplete.pass.cpp
index 12c95353cf6e8186415f39a953cbd3328403732c..b77f679fef5c3b5c57d2bfd2c2593decc561c367 100644
--- a/libcxx/test/std/containers/unord/unord.set/incomplete.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/incomplete.pass.cpp
@@ -32,6 +32,8 @@ struct A {
 
 inline bool operator==(A const& L, A const& R) { return &L == &R; }
 
-int main() {
+int main(int, char**) {
     A a;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/insert_and_emplace_allocator_requirements.pass.cpp b/libcxx/test/std/containers/unord/unord.set/insert_and_emplace_allocator_requirements.pass.cpp
index fffd108a783376402870c68129d78fe2744db605..34905e3c8dcf1814f1a5ebfb57321c04af6c3892 100644
--- a/libcxx/test/std/containers/unord/unord.set/insert_and_emplace_allocator_requirements.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/insert_and_emplace_allocator_requirements.pass.cpp
@@ -21,8 +21,10 @@
 #include "../../set_allocator_requirement_test_templates.h"
 
 
-int main()
+int main(int, char**)
 {
   testSetInsert<TCT::unordered_set<> >();
   testSetEmplace<TCT::unordered_set<> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/insert_const_lvalue.pass.cpp b/libcxx/test/std/containers/unord/unord.set/insert_const_lvalue.pass.cpp
index 820ac6e907c31e67fdc8c5bf1e17ac9628cb32fd..097b221a65bd03eaa694aab4d8e709d03ec932d1 100644
--- a/libcxx/test/std/containers/unord/unord.set/insert_const_lvalue.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/insert_const_lvalue.pass.cpp
@@ -50,7 +50,7 @@ void do_insert_const_lvalue_test()
     assert(r.second);
 }
 
-int main()
+int main(int, char**)
 {
     do_insert_const_lvalue_test<std::unordered_set<double> >();
 #if TEST_STD_VER >= 11
@@ -60,4 +60,6 @@ int main()
         do_insert_const_lvalue_test<C>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/insert_hint_const_lvalue.pass.cpp b/libcxx/test/std/containers/unord/unord.set/insert_hint_const_lvalue.pass.cpp
index 3ca654764a1cf5ce9bd4687e8715cdbb58485618..e3765ca02cb3e8db0cf2c67edf4b8da28f49e347 100644
--- a/libcxx/test/std/containers/unord/unord.set/insert_hint_const_lvalue.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/insert_hint_const_lvalue.pass.cpp
@@ -51,7 +51,7 @@ void do_insert_hint_const_lvalue_test()
     assert(*r == 5.5);
 }
 
-int main()
+int main(int, char**)
 {
     do_insert_hint_const_lvalue_test<std::unordered_set<double> >();
 #if TEST_STD_VER >= 11
@@ -74,4 +74,6 @@ int main()
         assert(false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/insert_hint_rvalue.pass.cpp b/libcxx/test/std/containers/unord/unord.set/insert_hint_rvalue.pass.cpp
index f4a38dcfbef95d832a9cb5d5d38f328a98ce5e8b..071708e1eacdfd66756aca5012f1991469ce7e36 100644
--- a/libcxx/test/std/containers/unord/unord.set/insert_hint_rvalue.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/insert_hint_rvalue.pass.cpp
@@ -21,7 +21,7 @@
 #include "MoveOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<double> C;
@@ -115,4 +115,6 @@ int main()
         assert(*r == 5);
     }
 #endif // TEST_STD_VER >= 11
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/insert_init.pass.cpp b/libcxx/test/std/containers/unord/unord.set/insert_init.pass.cpp
index 2af3d37328707339be82b3a1cfedfbdc18e703e3..c60fcb16bff22d04e319347feb1709d212809245 100644
--- a/libcxx/test/std/containers/unord/unord.set/insert_init.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/insert_init.pass.cpp
@@ -22,7 +22,7 @@
 #include "test_iterators.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int> C;
@@ -65,4 +65,6 @@ int main()
         assert(c.count(3) == 1);
         assert(c.count(4) == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/insert_node_type.pass.cpp b/libcxx/test/std/containers/unord/unord.set/insert_node_type.pass.cpp
index 8eed6586556a3043f8b8cd685c11a66100a7fcd5..f41c936857baca1543cc9d2a1725d9670a8c552d 100644
--- a/libcxx/test/std/containers/unord/unord.set/insert_node_type.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/insert_node_type.pass.cpp
@@ -73,10 +73,12 @@ void test(Container& c)
     }
 }
 
-int main()
+int main(int, char**)
 {
     std::unordered_set<int> m;
     test(m);
     std::unordered_set<int, std::hash<int>, std::equal_to<int>, min_allocator<int>> m2;
     test(m2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/insert_node_type_hint.pass.cpp b/libcxx/test/std/containers/unord/unord.set/insert_node_type_hint.pass.cpp
index bf8c12776499569d2a5d7df50920a3c25f4b4dc5..ae5e8976e48f5ded4289e0016850548ee6b0e200 100644
--- a/libcxx/test/std/containers/unord/unord.set/insert_node_type_hint.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/insert_node_type_hint.pass.cpp
@@ -51,10 +51,12 @@ void test(Container& c)
     }
 }
 
-int main()
+int main(int, char**)
 {
     std::unordered_set<int> m;
     test(m);
     std::unordered_set<int, std::hash<int>, std::equal_to<int>, min_allocator<int>> m2;
     test(m2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/insert_range.pass.cpp b/libcxx/test/std/containers/unord/unord.set/insert_range.pass.cpp
index d0c4d7e85d1b6b5a62268996e90ed55f84182241..cb365483a9db914dcdd45cb39fefd92aac1713b2 100644
--- a/libcxx/test/std/containers/unord/unord.set/insert_range.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/insert_range.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_iterators.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int> C;
@@ -66,4 +66,6 @@ int main()
         assert(c.count(4) == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/insert_rvalue.pass.cpp b/libcxx/test/std/containers/unord/unord.set/insert_rvalue.pass.cpp
index 75342b7c3bcc1be8cae564351c05ed5046443303..9edab2740415576ce3fbc205c1627b57e34bfa80 100644
--- a/libcxx/test/std/containers/unord/unord.set/insert_rvalue.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/insert_rvalue.pass.cpp
@@ -21,7 +21,7 @@
 #include "MoveOnly.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<double> C;
@@ -127,4 +127,6 @@ int main()
         assert(r.second);
     }
 #endif // TEST_STD_VER >= 11
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/iterators.fail.cpp b/libcxx/test/std/containers/unord/unord.set/iterators.fail.cpp
index 8ded4e0233ac24cd078e55bc5b4cda6b86a3ed60..de5f88e792fedfa14aa4ac106d17a9d13b71ee56 100644
--- a/libcxx/test/std/containers/unord/unord.set/iterators.fail.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/iterators.fail.cpp
@@ -22,7 +22,7 @@
 #include <unordered_set>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int> C;
@@ -63,4 +63,6 @@ int main()
         assert(std::distance(c.begin(), c.end()) == c.size());
         assert(std::distance(c.cbegin(), c.cend()) == c.size());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/iterators.pass.cpp b/libcxx/test/std/containers/unord/unord.set/iterators.pass.cpp
index 73b1a4c5402879e4530e65faf976e2bf3c9b0aca..eb8459101b2a289bb7e8729c7afa71bc98cb4c2c 100644
--- a/libcxx/test/std/containers/unord/unord.set/iterators.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/iterators.pass.cpp
@@ -26,7 +26,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int> C;
@@ -125,4 +125,6 @@ int main()
         assert (!(cii != ii1 ));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/load_factor.pass.cpp b/libcxx/test/std/containers/unord/unord.set/load_factor.pass.cpp
index 06d17dc905c4695c1e81b32bd2420c80a8e6a606..c5857b7b47c88d57e0e2badfc1d653ee925e1b98 100644
--- a/libcxx/test/std/containers/unord/unord.set/load_factor.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/load_factor.pass.cpp
@@ -21,7 +21,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int> C;
@@ -71,4 +71,6 @@ int main()
         assert(c.load_factor() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/local_iterators.fail.cpp b/libcxx/test/std/containers/unord/unord.set/local_iterators.fail.cpp
index b7c3d9b6b5446056480d50199d7d1950ad6f44fa..7bacd2f6f7653952f82a24470c1a13f0db6b439d 100644
--- a/libcxx/test/std/containers/unord/unord.set/local_iterators.fail.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/local_iterators.fail.cpp
@@ -22,7 +22,7 @@
 #include <unordered_set>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int> C;
@@ -257,4 +257,6 @@ int main()
         j = c.cend(b);
         assert(std::distance(i, j) == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/local_iterators.pass.cpp b/libcxx/test/std/containers/unord/unord.set/local_iterators.pass.cpp
index 0797c1ec8b9e1437405296ee64766f531073049e..ad3de5b0ae0d7b9b7adfe617c685700710e1aa70 100644
--- a/libcxx/test/std/containers/unord/unord.set/local_iterators.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/local_iterators.pass.cpp
@@ -24,7 +24,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int> C;
@@ -384,4 +384,6 @@ int main()
         assert(*i == 4);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/max_bucket_count.pass.cpp b/libcxx/test/std/containers/unord/unord.set/max_bucket_count.pass.cpp
index 88471bbaf8e18489424329be97f1f6183c572b60..121147a08e7c5af09faa57bcaf2e1a4e3ca4dbfe 100644
--- a/libcxx/test/std/containers/unord/unord.set/max_bucket_count.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/max_bucket_count.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int> C;
@@ -34,4 +34,6 @@ int main()
         assert(c.max_bucket_count() > 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/max_load_factor.pass.cpp b/libcxx/test/std/containers/unord/unord.set/max_load_factor.pass.cpp
index 35028a827d1eaf45b67212f1da166d54e618220d..ac345a1d4ea2b6d7c8831d1666064e8ac5a5eb06 100644
--- a/libcxx/test/std/containers/unord/unord.set/max_load_factor.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/max_load_factor.pass.cpp
@@ -24,7 +24,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int> C;
@@ -62,4 +62,6 @@ int main()
         assert(false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/max_size.pass.cpp b/libcxx/test/std/containers/unord/unord.set/max_size.pass.cpp
index 5ec2af75b74606dd5c146e03d25799539ee84b67..aeb1354da56218dce64a4a5f1d130ba99339ffba 100644
--- a/libcxx/test/std/containers/unord/unord.set/max_size.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/max_size.pass.cpp
@@ -20,7 +20,7 @@
 #include "test_allocator.h"
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
       typedef limited_allocator<int, 10> A;
@@ -46,4 +46,6 @@ int main()
       assert(c.max_size() <= max_dist);
       assert(c.max_size() <= alloc_max_size(c.get_allocator()));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/merge.pass.cpp b/libcxx/test/std/containers/unord/unord.set/merge.pass.cpp
index 91dd476d4f9acbe7bcc4541843a0f24f3438cd11..4a11867ed2adc41d0b6b27f586a40ada90a3630c 100644
--- a/libcxx/test/std/containers/unord/unord.set/merge.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/merge.pass.cpp
@@ -49,7 +49,7 @@ struct throw_hasher
 };
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         std::unordered_set<int> src{1, 3, 5};
@@ -150,4 +150,5 @@ int main()
             first.merge(std::move(second));
         }
     }
+    return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/rehash.pass.cpp b/libcxx/test/std/containers/unord/unord.set/rehash.pass.cpp
index c373b1632d52ddda91771138a704f3db42d2f9f2..e45327ad7ec51613dad3d70675e9bf56d952d4f4 100644
--- a/libcxx/test/std/containers/unord/unord.set/rehash.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/rehash.pass.cpp
@@ -36,7 +36,7 @@ void test(const C& c)
     assert(c.count(4) == 1);
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int> C;
@@ -99,4 +99,6 @@ int main()
         test(c);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/reserve.pass.cpp b/libcxx/test/std/containers/unord/unord.set/reserve.pass.cpp
index a852f10223da960c66e6c1580169c5f0d5442e1e..7ea358e889d48714c190a8b573578ec1b398310c 100644
--- a/libcxx/test/std/containers/unord/unord.set/reserve.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/reserve.pass.cpp
@@ -45,7 +45,7 @@ void reserve_invariant(size_t n) // LWG #2156
     }
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int> C;
@@ -103,4 +103,6 @@ int main()
     }
 #endif
     reserve_invariant(20);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/size.pass.cpp b/libcxx/test/std/containers/unord/unord.set/size.pass.cpp
index e3e488461c97cb52bbd580e978c44619610fc1d3..f7967fcd5f7a5fbcdca01748577cd9f8aac55265 100644
--- a/libcxx/test/std/containers/unord/unord.set/size.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/size.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::unordered_set<int> M;
@@ -58,4 +58,6 @@ int main()
     assert(m.size() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/swap_member.pass.cpp b/libcxx/test/std/containers/unord/unord.set/swap_member.pass.cpp
index 9c34e8de9c5b3d073b664827c469b63bdae37e5b..0877b14f763f24a6f471e23c74f312a9ce1d532e 100644
--- a/libcxx/test/std/containers/unord/unord.set/swap_member.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/swap_member.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef test_hash<std::hash<int> > Hash;
@@ -566,4 +566,6 @@ int main()
         assert(c2.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/types.pass.cpp b/libcxx/test/std/containers/unord/unord.set/types.pass.cpp
index 7beafedc2c5dbfe8badb87a87ac3960c2aa63252..7b1531dc28f6e11ad5f1a6686879ddeb44eaa467 100644
--- a/libcxx/test/std/containers/unord/unord.set/types.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/types.pass.cpp
@@ -31,7 +31,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<short> C;
@@ -65,4 +65,6 @@ int main()
         static_assert((std::is_same<C::difference_type, std::ptrdiff_t>::value), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/allocator.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/allocator.pass.cpp
index d6e604d72024ab3f43f3cc0f9a36507135de2ffd..920244aae82424cf196e4994b540c16c9354281b 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/allocator.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/allocator.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<NotConstructible,
@@ -106,4 +106,6 @@ int main()
     }
 #endif
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/assign_copy.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/assign_copy.pass.cpp
index 083ebda3f2a87f5fb68cff851cf3495f76eaccf7..10952954284eafc0b85cd8f3d403edf4d57abb61 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/assign_copy.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/assign_copy.pass.cpp
@@ -27,7 +27,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef test_allocator<int> A;
@@ -184,4 +184,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/assign_init.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/assign_init.pass.cpp
index 515022124a44b47a7aacf62a5b689f123d89442f..bbb2045cb9cabd908aca201aa1a549d8195f5877 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/assign_init.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/assign_init.pass.cpp
@@ -27,7 +27,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef test_allocator<int> A;
@@ -93,4 +93,6 @@ int main()
         assert(fabs(c.load_factor() - (float)c.size()/c.bucket_count()) < FLT_EPSILON);
         assert(c.max_load_factor() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/assign_move.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/assign_move.pass.cpp
index 9c8d055a9458ac23f445bb951fbde586fec37c24..15741254d9648d9532ae8aab21bdea7dceb087d7 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/assign_move.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/assign_move.pass.cpp
@@ -28,7 +28,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef test_allocator<int> A;
@@ -210,4 +210,6 @@ int main()
         assert(fabs(c.load_factor() - (float)c.size()/c.bucket_count()) < FLT_EPSILON);
         assert(c.max_load_factor() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/compare_copy_constructible.fail.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/compare_copy_constructible.fail.cpp
index 21cd61458c6a4aa41d76447a87777f28f9252b6f..0638027fd814bcab05a86bebf8a85bab36f347e2 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/compare_copy_constructible.fail.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/compare_copy_constructible.fail.cpp
@@ -23,6 +23,8 @@ private:
     };
 
 
-int main() {
+int main(int, char**) {
     std::unordered_set<int, std::hash<int>, Comp<int> > m;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/copy.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/copy.pass.cpp
index 652f2e4a44207e96295c93c4187e27edf4e7de15..179e6e473c8f12ff8b60c6bc8a74bc00605c6518 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/copy.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/copy.pass.cpp
@@ -26,7 +26,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int,
@@ -144,4 +144,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/copy_alloc.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/copy_alloc.pass.cpp
index 800f4f36ad093949d825bc5f71fb2aa8a4794029..970da0877174296b0d3ee8b1411153e7c1584b6f 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/copy_alloc.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/copy_alloc.pass.cpp
@@ -26,7 +26,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int,
@@ -106,4 +106,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/default.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/default.pass.cpp
index 52cda0692d9889101a18048ffa175ca1cc98a975..1fa2932e5a52e5ae05d62e206958fcad5f618754 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/default.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/default.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<NotConstructible,
@@ -104,4 +104,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/default_noexcept.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/default_noexcept.pass.cpp
index 533c10df4c0afb5dd3479768da8dd68f3daed5fb..5d6508d464b090b76e9833af282c1ceb57495d50 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/default_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/default_noexcept.pass.cpp
@@ -44,7 +44,7 @@ struct some_hash
     std::size_t operator()(T const&) const;
 };
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -71,4 +71,6 @@ int main()
                                                          some_comp<MoveOnly>> C;
         static_assert(!std::is_nothrow_default_constructible<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/dtor_noexcept.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/dtor_noexcept.pass.cpp
index 7041c8263a45af5ff87d13094d368cf2c842aa58..2225469e9e5ab8584d8cae28dfd29e090dc376a1 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/dtor_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/dtor_noexcept.pass.cpp
@@ -37,7 +37,7 @@ struct some_hash
     std::size_t operator()(T const&) const;
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<MoveOnly> C;
@@ -64,4 +64,6 @@ int main()
         static_assert(!std::is_nothrow_destructible<C>::value, "");
     }
 #endif // _LIBCPP_VERSION
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/hash_copy_constructible.fail.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/hash_copy_constructible.fail.cpp
index 0ddae66710c4d55758f6a929f6a38e038723e019..92550a0962fac244c6e18358c526fd416a0a8654 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/hash_copy_constructible.fail.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/hash_copy_constructible.fail.cpp
@@ -23,6 +23,8 @@ private:
     };
 
 
-int main() {
+int main(int, char**) {
     std::unordered_set<int, Hash<int> > m;
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/init.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/init.pass.cpp
index 1550727d8feac8b1c17c645fef00604880d7ed8c..8bf0453c32052e97ba90a736d3a4bb13c8497515 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/init.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/init.pass.cpp
@@ -28,7 +28,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
   {
         typedef std::unordered_set<int,
@@ -160,4 +160,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/init_size.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/init_size.pass.cpp
index 54b6fbd7185c684396b9a28c9fcd42b143a71ea3..3e58ce92836fe88969a725aa4e0d8237789446e2 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/init_size.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/init_size.pass.cpp
@@ -28,7 +28,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int,
@@ -94,4 +94,6 @@ int main()
         assert(std::fabs(c.load_factor() - (float)c.size()/c.bucket_count()) < FLT_EPSILON);
         assert(c.max_load_factor() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/init_size_hash.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/init_size_hash.pass.cpp
index d7330c3bd76e1ac90a66e9d03cbae6fe85143ac9..3761cc33dde254cbf55b59e93d41d81380df78ae 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/init_size_hash.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/init_size_hash.pass.cpp
@@ -29,7 +29,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int,
@@ -97,4 +97,6 @@ int main()
         assert(std::fabs(c.load_factor() - (float)c.size()/c.bucket_count()) < FLT_EPSILON);
         assert(c.max_load_factor() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/init_size_hash_equal.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/init_size_hash_equal.pass.cpp
index 1741320bc952db96321a1f12b6098a3df4a3e8f7..7123e3415090e860ebeb027fbea10ddd41140f4d 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/init_size_hash_equal.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/init_size_hash_equal.pass.cpp
@@ -29,7 +29,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int,
@@ -99,4 +99,6 @@ int main()
         assert(std::fabs(c.load_factor() - (float)c.size()/c.bucket_count()) < FLT_EPSILON);
         assert(c.max_load_factor() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/init_size_hash_equal_allocator.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/init_size_hash_equal_allocator.pass.cpp
index ac13691693e87431a12306ef6bb3fd145e76e871..94aa74f2434489745a5848efeb74e6acdade2913 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/init_size_hash_equal_allocator.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/init_size_hash_equal_allocator.pass.cpp
@@ -29,7 +29,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int,
@@ -101,4 +101,6 @@ int main()
         assert(std::fabs(c.load_factor() - (float)c.size()/c.bucket_count()) < FLT_EPSILON);
         assert(c.max_load_factor() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/move.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/move.pass.cpp
index 0bbf312bd68cb7f124907f9420ed198eef65b3de..5b599ae71d4c6ccf2a947bb9c923edf9ea68ff9c 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/move.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/move.pass.cpp
@@ -28,7 +28,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int,
@@ -171,4 +171,6 @@ int main()
         assert(s2.size() == 2);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/move_alloc.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/move_alloc.pass.cpp
index 03567db22a1c026c48d1524ff8cb6e68e0ab6eb3..bc6629acdb728cb351573c997e9c0c1a34bee108 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/move_alloc.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/move_alloc.pass.cpp
@@ -27,7 +27,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int P;
@@ -152,4 +152,6 @@ int main()
 
         assert(c0.empty());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/move_assign_noexcept.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/move_assign_noexcept.pass.cpp
index c91d972f3fcc5dbe8562da8b79b83c46fbde0bbe..dba99837d07347cf7a7ecdb66221c4700bb58882 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/move_assign_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/move_assign_noexcept.pass.cpp
@@ -43,7 +43,7 @@ struct some_hash
     std::size_t operator()(T const&) const;
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<MoveOnly> C;
@@ -70,4 +70,6 @@ int main()
                                                          some_comp<MoveOnly>> C;
         static_assert(!std::is_nothrow_move_assignable<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/move_noexcept.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/move_noexcept.pass.cpp
index 86a058b076b9825ef6d9535625c69f46b9bb2378..49802f689f33adae013e141f236a9f953d522ce7 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/move_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/move_noexcept.pass.cpp
@@ -40,7 +40,7 @@ struct some_hash
     std::size_t operator()(T const&) const;
 };
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -67,4 +67,6 @@ int main()
                                                          some_comp<MoveOnly>> C;
         static_assert(!std::is_nothrow_move_constructible<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/range.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/range.pass.cpp
index 182ce8bee4d3c0fdcb6e13b71ead37e64f271f65..dfa46ec568653de1a544e7915b01dbf94ebd1d99 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/range.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/range.pass.cpp
@@ -28,7 +28,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int,
@@ -167,4 +167,6 @@ int main()
 
 #endif
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/range_size.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/range_size.pass.cpp
index 0c90055eb37036fe2052dc0e4ed5df42fe2308d7..1115044e02227a6dc4aac5ff27cd48816b75c932 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/range_size.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/range_size.pass.cpp
@@ -28,7 +28,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int,
@@ -100,4 +100,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/range_size_hash.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/range_size_hash.pass.cpp
index 3805b7f32cb49d3c784fe6f028cf226683075e55..2acbb2d18fa089bbf952ea2eb175e02ecf0199ba 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/range_size_hash.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/range_size_hash.pass.cpp
@@ -29,7 +29,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int,
@@ -103,4 +103,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/range_size_hash_equal.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/range_size_hash_equal.pass.cpp
index 3fc872236334463896d453ab3ec0a4886e62a833..245e12476086312992a26feab42a8eddadcd4adf 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/range_size_hash_equal.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/range_size_hash_equal.pass.cpp
@@ -29,7 +29,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int,
@@ -105,4 +105,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/range_size_hash_equal_allocator.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/range_size_hash_equal_allocator.pass.cpp
index 8d73e92dbd45d987c6cde39e41815cbd855c3257..002466496763cc3ffc680c8419f27054a6e8ba2f 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/range_size_hash_equal_allocator.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/range_size_hash_equal_allocator.pass.cpp
@@ -30,7 +30,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<int,
@@ -108,4 +108,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/size.fail.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/size.fail.cpp
index 4ed509633e5ae4e6a9b77b3b11dd2dafef7617f0..da3dc1855774a77b0f59756e00076120611939fe 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/size.fail.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/size.fail.cpp
@@ -23,7 +23,7 @@
 #include "../../../test_hash.h"
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<NotConstructible,
@@ -42,4 +42,6 @@ int main()
         assert(c.load_factor() == 0);
         assert(c.max_load_factor() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/size.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/size.pass.cpp
index d637705294325b4b3c38af9d90f390bc1b639686..12ba6201a1b5e621c9149da16fcea0cfa34e3850 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/size.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/size.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<NotConstructible,
@@ -62,4 +62,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/size_hash.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/size_hash.pass.cpp
index 4ded899f6a5fdc94517e86adb959d8b7c6fbfd5d..60134b7fad2ac88c1c7f612e32c690a0238b16ee 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/size_hash.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/size_hash.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<NotConstructible,
@@ -66,4 +66,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/size_hash_equal.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/size_hash_equal.pass.cpp
index 36f104dfb9ac6bc68b0e3a98a54317461900b0d8..49e12ea29d9ccea27929f19ba6c5336749f8ea32 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/size_hash_equal.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/size_hash_equal.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<NotConstructible,
@@ -68,4 +68,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/size_hash_equal_allocator.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/size_hash_equal_allocator.pass.cpp
index bb14b27a916369fe1790599fe396d3c94bccc463..43eb1f7170365225d62bad6abff9b2f4fae9245c 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/size_hash_equal_allocator.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/size_hash_equal_allocator.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<NotConstructible,
@@ -70,4 +70,6 @@ int main()
         assert(c.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.swap/db_swap_1.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.swap/db_swap_1.pass.cpp
index 5ea0aa38f75e3d1085212bf5f351f604cecc93ef..f14f0ddeb7bcdbc86e3a4722b7da844496ccb92c 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.swap/db_swap_1.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.swap/db_swap_1.pass.cpp
@@ -21,7 +21,7 @@
 #include <unordered_set>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
 #if _LIBCPP_DEBUG >= 1
     {
@@ -39,4 +39,6 @@ int main()
         assert(false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.swap/swap_noexcept.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.swap/swap_noexcept.pass.cpp
index 61371306ef09a446fd0a34f33a570d7376704e59..40bf1894d76241eb565b3cb6f47b97fe809570f0 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.swap/swap_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.swap/swap_noexcept.pass.cpp
@@ -118,7 +118,7 @@ struct some_alloc3
     typedef std::false_type is_always_equal;
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unordered_set<MoveOnly> C;
@@ -186,4 +186,6 @@ int main()
     }
 #endif // _LIBCPP_VERSION
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/unord/unord.set/unord.set.swap/swap_non_member.pass.cpp b/libcxx/test/std/containers/unord/unord.set/unord.set.swap/swap_non_member.pass.cpp
index aad68658a3b2f59cc125ce94b2a3b4c6939f4ea8..8f1d9f0c3ee37f469526857f75664684b55b85ee 100644
--- a/libcxx/test/std/containers/unord/unord.set/unord.set.swap/swap_non_member.pass.cpp
+++ b/libcxx/test/std/containers/unord/unord.set/unord.set.swap/swap_non_member.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef test_hash<std::hash<int> > Hash;
@@ -566,4 +566,6 @@ int main()
         assert(c2.max_load_factor() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.cons/array.fail.cpp b/libcxx/test/std/containers/views/span.cons/array.fail.cpp
index 7e9d85dcdcb8736e630eadf45acb5ffb9402d004..f6164977187770094a2af2ab510314b192ea70d3 100644
--- a/libcxx/test/std/containers/views/span.cons/array.fail.cpp
+++ b/libcxx/test/std/containers/views/span.cons/array.fail.cpp
@@ -34,7 +34,7 @@ const          int  carr[] = {4,5,6};
       volatile int  varr[] = {7,8,9};
 const volatile int cvarr[] = {1,3,5};
 
-int main ()
+int main(int, char**)
 {
 //  Size wrong
     {
@@ -68,4 +68,6 @@ int main ()
     std::span<      volatile int,3> s6{ carr};  // expected-error {{no matching constructor for initialization of 'std::span<volatile int, 3>'}}
     std::span<      volatile int,3> s7{cvarr};  // expected-error {{no matching constructor for initialization of 'std::span<volatile int, 3>'}}
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.cons/array.pass.cpp b/libcxx/test/std/containers/views/span.cons/array.pass.cpp
index d9d1029b623aff960050f3fcae76aecb0967b1cf..5ac7e1a4a19dd90992669877d262cf2c4b4356eb 100644
--- a/libcxx/test/std/containers/views/span.cons/array.pass.cpp
+++ b/libcxx/test/std/containers/views/span.cons/array.pass.cpp
@@ -105,7 +105,7 @@ void testRuntimeSpan()
 
 struct A{};
 
-int main ()
+int main(int, char**)
 {
     static_assert(testConstexprSpan<int>(),    "");
     static_assert(testConstexprSpan<long>(),   "");
@@ -119,4 +119,6 @@ int main ()
     testRuntimeSpan<A>();
 
     checkCV();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.cons/assign.pass.cpp b/libcxx/test/std/containers/views/span.cons/assign.pass.cpp
index ea6028ad065e1245e918c68bf1fc249b9c1a301c..3f8d5f418628f747f0a9dcb51f3c5d8a536381ac 100644
--- a/libcxx/test/std/containers/views/span.cons/assign.pass.cpp
+++ b/libcxx/test/std/containers/views/span.cons/assign.pass.cpp
@@ -37,7 +37,7 @@ constexpr int carr3[] = {7,8};
 std::string strs[] = {"ABC", "DEF", "GHI"};
 
 
-int main ()
+int main(int, char**)
 {
 
 //  constexpr dynamically sized assignment
@@ -289,4 +289,6 @@ int main ()
             for (size_t j = i; j < std::size(spans); ++j)
                 assert((doAssign(spans[i], spans[j])));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.cons/container.fail.cpp b/libcxx/test/std/containers/views/span.cons/container.fail.cpp
index cfffa57a1e3db9e4a882c0189a21ec490cdadf0d..d0fb5656d21e3a1d86cfe1093603756f70698fbb 100644
--- a/libcxx/test/std/containers/views/span.cons/container.fail.cpp
+++ b/libcxx/test/std/containers/views/span.cons/container.fail.cpp
@@ -63,7 +63,7 @@ private:
 };
 
 
-int main ()
+int main(int, char**)
 {
 
 //  Making non-const spans from const sources (a temporary binds to `const &`)
@@ -129,4 +129,6 @@ int main ()
     std::span<      volatile int,1> s7{cv}; // expected-error {{no matching constructor for initialization of 'std::span<volatile int, 1>'}}
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.cons/container.pass.cpp b/libcxx/test/std/containers/views/span.cons/container.pass.cpp
index 4e9001bff8de6b6eec107470260175873e35b0c5..07aac9229f09940d112a824b4607e50c632f540a 100644
--- a/libcxx/test/std/containers/views/span.cons/container.pass.cpp
+++ b/libcxx/test/std/containers/views/span.cons/container.pass.cpp
@@ -117,7 +117,7 @@ void testRuntimeSpan()
 
 struct A{};
 
-int main ()
+int main(int, char**)
 {
     static_assert(testConstexprSpan<int>(),    "");
     static_assert(testConstexprSpan<long>(),   "");
@@ -131,4 +131,6 @@ int main ()
     testRuntimeSpan<A>();
 
     checkCV();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.cons/copy.pass.cpp b/libcxx/test/std/containers/views/span.cons/copy.pass.cpp
index 1ccb679ce94b586ab23f13ac64777f1705aeffa4..2ad1cded2165a4f0bc75995afe143393c367c4c4 100644
--- a/libcxx/test/std/containers/views/span.cons/copy.pass.cpp
+++ b/libcxx/test/std/containers/views/span.cons/copy.pass.cpp
@@ -42,7 +42,7 @@ void testCV ()
 }
 
 
-int main ()
+int main(int, char**)
 {
     constexpr int carr[] = {1,2,3};
 
@@ -67,4 +67,6 @@ int main ()
     testCV<const          int>();
     testCV<      volatile int>();
     testCV<const volatile int>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.cons/deduct.pass.cpp b/libcxx/test/std/containers/views/span.cons/deduct.pass.cpp
index 7c533883658960ed7c53b4170b9dcf75775ef26d..188463bc31f839cdf64cfb5f271d34afefef91fe 100644
--- a/libcxx/test/std/containers/views/span.cons/deduct.pass.cpp
+++ b/libcxx/test/std/containers/views/span.cons/deduct.pass.cpp
@@ -40,7 +40,7 @@
 // Disable the missing braces warning for this reason.
 #include "disable_missing_braces_warning.h"
 
-int main ()
+int main(int, char**)
 {
     {
     int arr[] = {1,2,3};
@@ -83,4 +83,6 @@ int main ()
     assert((size_t)s.size() == str.size());
     assert((std::equal(s.begin(), s.end(), std::begin(s), std::end(s))));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.cons/default.fail.cpp b/libcxx/test/std/containers/views/span.cons/default.fail.cpp
index 309f7180c18ede8045ffaa7991d8fe236beaa798..24ff77477bd2e59e0a9dd9721028be3022a2fa68 100644
--- a/libcxx/test/std/containers/views/span.cons/default.fail.cpp
+++ b/libcxx/test/std/containers/views/span.cons/default.fail.cpp
@@ -22,10 +22,12 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     std::span<int, 2> s; // expected-error-re@span:* {{static_assert failed{{( due to requirement '2[LL]{0,2} == 0')?}} "Can't default construct a statically sized span with size > 0"}}
 
 //  TODO: This is what I want:
 // eXpected-error {{no matching constructor for initialization of 'std::span<int, 2>'}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.cons/default.pass.cpp b/libcxx/test/std/containers/views/span.cons/default.pass.cpp
index 431b7e90bafbde7df66f324b341b98c243865508..867026bd9aecc3390af646efd9eadc277b536ad3 100644
--- a/libcxx/test/std/containers/views/span.cons/default.pass.cpp
+++ b/libcxx/test/std/containers/views/span.cons/default.pass.cpp
@@ -64,7 +64,7 @@ void testRuntimeSpan()
 
 struct A{};
 
-int main ()
+int main(int, char**)
 {
     static_assert(testConstexprSpan<int>(),    "");
     static_assert(testConstexprSpan<long>(),   "");
@@ -78,4 +78,6 @@ int main ()
     testRuntimeSpan<A>();
 
     checkCV();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.cons/ptr_len.fail.cpp b/libcxx/test/std/containers/views/span.cons/ptr_len.fail.cpp
index ad63c69b3ea63f8fe460e6831bb2b73ec631624b..d407ae7793645f4fbcacf4827c55ac5794516b4b 100644
--- a/libcxx/test/std/containers/views/span.cons/ptr_len.fail.cpp
+++ b/libcxx/test/std/containers/views/span.cons/ptr_len.fail.cpp
@@ -27,7 +27,7 @@ const          int  carr[] = {4,5,6};
       volatile int  varr[] = {7,8,9};
 const volatile int cvarr[] = {1,3,5};
 
-int main ()
+int main(int, char**)
 {
 //  We can't check that the size doesn't match - because that's a runtime property
 //  std::span<int, 2>   s1(arr, 3);
@@ -59,4 +59,6 @@ int main ()
     std::span<      volatile int,3> s6{ carr, 3};   // expected-error {{no matching constructor for initialization of 'std::span<volatile int, 3>'}}
     std::span<      volatile int,3> s7{cvarr, 3};   // expected-error {{no matching constructor for initialization of 'std::span<volatile int, 3>'}}
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.cons/ptr_len.pass.cpp b/libcxx/test/std/containers/views/span.cons/ptr_len.pass.cpp
index a1a93c71fabfcd82c77ae20ed383926e9e82a4a5..2a4b260c87dd762f2ff192858b7ed5c4daca1d20 100644
--- a/libcxx/test/std/containers/views/span.cons/ptr_len.pass.cpp
+++ b/libcxx/test/std/containers/views/span.cons/ptr_len.pass.cpp
@@ -95,7 +95,7 @@ void testRuntimeSpan()
 
 struct A{};
 
-int main ()
+int main(int, char**)
 {
     static_assert(testConstexprSpan<int>(),    "");
     static_assert(testConstexprSpan<long>(),   "");
@@ -109,4 +109,6 @@ int main ()
     testRuntimeSpan<A>();
 
     checkCV();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.cons/ptr_ptr.fail.cpp b/libcxx/test/std/containers/views/span.cons/ptr_ptr.fail.cpp
index 0bda60c3f023236ea8c0de9daadaf20f7604ef2c..9c15ea58c9529071c563521013b8dfc248f800c2 100644
--- a/libcxx/test/std/containers/views/span.cons/ptr_ptr.fail.cpp
+++ b/libcxx/test/std/containers/views/span.cons/ptr_ptr.fail.cpp
@@ -27,7 +27,7 @@ const          int  carr[] = {4,5,6};
       volatile int  varr[] = {7,8,9};
 const volatile int cvarr[] = {1,3,5};
 
-int main ()
+int main(int, char**)
 {
 //  We can't check that the size doesn't match - because that's a runtime property
 //  std::span<int, 2>   s1(arr, arr + 3);
@@ -59,4 +59,6 @@ int main ()
     std::span<      volatile int,3> s6{ carr,  carr + 3};   // expected-error {{no matching constructor for initialization of 'std::span<volatile int, 3>'}}
     std::span<      volatile int,3> s7{cvarr, cvarr + 3};   // expected-error {{no matching constructor for initialization of 'std::span<volatile int, 3>'}}
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.cons/ptr_ptr.pass.cpp b/libcxx/test/std/containers/views/span.cons/ptr_ptr.pass.cpp
index 1d693e39244d399b70e8849d93bebae3b9cf4fe8..15c9f303ecb5a900eb09c01f96e28bd2622acb00 100644
--- a/libcxx/test/std/containers/views/span.cons/ptr_ptr.pass.cpp
+++ b/libcxx/test/std/containers/views/span.cons/ptr_ptr.pass.cpp
@@ -95,7 +95,7 @@ void testRuntimeSpan()
 
 struct A{};
 
-int main ()
+int main(int, char**)
 {
     static_assert(testConstexprSpan<int>(),    "");
     static_assert(testConstexprSpan<long>(),   "");
@@ -109,4 +109,6 @@ int main ()
     testRuntimeSpan<A>();
 
     checkCV();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.cons/span.fail.cpp b/libcxx/test/std/containers/views/span.cons/span.fail.cpp
index 132d1b15226c995210492a94c4452b476cb1e387..f559b1fb0c29d5a2713a0e4990c884e81465a4e2 100644
--- a/libcxx/test/std/containers/views/span.cons/span.fail.cpp
+++ b/libcxx/test/std/containers/views/span.cons/span.fail.cpp
@@ -89,7 +89,7 @@ void checkCV ()
     }
 }
 
-int main ()
+int main(int, char**)
 {
     std::span<int>      sp;
     std::span<int, 0>   sp0;
@@ -100,4 +100,6 @@ int main ()
     std::span<float, 0> s4{sp0};    // expected-error {{no matching constructor for initialization of 'std::span<float, 0>'}}
 
     checkCV();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.cons/span.pass.cpp b/libcxx/test/std/containers/views/span.cons/span.pass.cpp
index 8ace94f5e0583f4829c7b02eac3b9da1c6e3fc4e..74da3fce894a1f0ccf5ce30f627299b1af86ee0b 100644
--- a/libcxx/test/std/containers/views/span.cons/span.pass.cpp
+++ b/libcxx/test/std/containers/views/span.cons/span.pass.cpp
@@ -121,7 +121,7 @@ bool testConversionSpan()
 
 struct A{};
 
-int main ()
+int main(int, char**)
 {
     static_assert(testConstexprSpan<int>(),    "");
     static_assert(testConstexprSpan<long>(),   "");
@@ -138,4 +138,6 @@ int main ()
 //  assert((testConversionSpan<unsigned char, char>()));
 
     checkCV();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.cons/stdarray.pass.cpp b/libcxx/test/std/containers/views/span.cons/stdarray.pass.cpp
index a0b37fe8e64b9d6fa5512959f8df30084fc1fd0d..03fdd253426085891c3fd12e30a277b4e1c94e71 100644
--- a/libcxx/test/std/containers/views/span.cons/stdarray.pass.cpp
+++ b/libcxx/test/std/containers/views/span.cons/stdarray.pass.cpp
@@ -96,7 +96,7 @@ void testRuntimeSpan()
 
 struct A{};
 
-int main ()
+int main(int, char**)
 {
     static_assert(testConstexprSpan<int>(),    "");
     static_assert(testConstexprSpan<long>(),   "");
@@ -110,4 +110,6 @@ int main ()
     testRuntimeSpan<A>();
 
     checkCV();
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.elem/data.pass.cpp b/libcxx/test/std/containers/views/span.elem/data.pass.cpp
index ca49eb8900a0785d5784377d3e8e8ea7fb544b9e..c858a7e11e335bf2b95bdc4874552f0cb30db951 100644
--- a/libcxx/test/std/containers/views/span.elem/data.pass.cpp
+++ b/libcxx/test/std/containers/views/span.elem/data.pass.cpp
@@ -40,7 +40,7 @@ struct A{};
 constexpr int iArr1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9};
           int iArr2[] = {10, 11, 12, 13, 14, 15, 16, 17, 18, 19};
 
-int main ()
+int main(int, char**)
 {
 
 //  dynamic size
@@ -117,4 +117,6 @@ int main ()
     testRuntimeSpan(std::span<std::string>(&s, 1), &s);
     testRuntimeSpan(std::span<std::string, 1>(&s, 1), &s);
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.elem/op_idx.pass.cpp b/libcxx/test/std/containers/views/span.elem/op_idx.pass.cpp
index d11032673fbfd0efecb960a0687172257b1970b3..c56be7d3e2cba233e685a0df63c6b9546f092098 100644
--- a/libcxx/test/std/containers/views/span.elem/op_idx.pass.cpp
+++ b/libcxx/test/std/containers/views/span.elem/op_idx.pass.cpp
@@ -51,7 +51,7 @@ struct A{};
 constexpr int iArr1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9};
           int iArr2[] = {10, 11, 12, 13, 14, 15, 16, 17, 18, 19};
 
-int main ()
+int main(int, char**)
 {
     static_assert(testConstexprSpan(std::span<const int>(iArr1, 1), 0), "");
 
@@ -115,4 +115,6 @@ int main ()
     std::string s;
     testRuntimeSpan(std::span<std::string>   (&s, 1), 0);
     testRuntimeSpan(std::span<std::string, 1>(&s, 1), 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.iterators/begin.pass.cpp b/libcxx/test/std/containers/views/span.iterators/begin.pass.cpp
index 0abae63ff2ff12edf3af20c3d610147bbaa6466a..e4532ade54e1723fea4e1b6c07f45a802adecc82 100644
--- a/libcxx/test/std/containers/views/span.iterators/begin.pass.cpp
+++ b/libcxx/test/std/containers/views/span.iterators/begin.pass.cpp
@@ -70,7 +70,7 @@ constexpr int iArr1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9};
           int iArr2[] = {10, 11, 12, 13, 14, 15, 16, 17, 18, 19};
 
 
-int main()
+int main(int, char**)
 {
     static_assert(testConstexprSpan(std::span<int>()),            "");
     static_assert(testConstexprSpan(std::span<long>()),           "");
@@ -112,4 +112,6 @@ int main()
     std::string s;
     testRuntimeSpan(std::span<std::string>(&s, (std::ptrdiff_t) 0));
     testRuntimeSpan(std::span<std::string>(&s, 1));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.iterators/end.pass.cpp b/libcxx/test/std/containers/views/span.iterators/end.pass.cpp
index a834804d1762a69122c048c5edc8133aeb703ca0..c52c8bc6004db99056f13dcc2022ec6e04f6b99c 100644
--- a/libcxx/test/std/containers/views/span.iterators/end.pass.cpp
+++ b/libcxx/test/std/containers/views/span.iterators/end.pass.cpp
@@ -78,7 +78,7 @@ constexpr int iArr1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9};
           int iArr2[] = {10, 11, 12, 13, 14, 15, 16, 17, 18, 19};
 
 
-int main()
+int main(int, char**)
 {
     static_assert(testConstexprSpan(std::span<int>()),            "");
     static_assert(testConstexprSpan(std::span<long>()),           "");
@@ -120,4 +120,6 @@ int main()
     std::string s;
     testRuntimeSpan(std::span<std::string>(&s, (std::ptrdiff_t) 0));
     testRuntimeSpan(std::span<std::string>(&s, 1));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.iterators/rbegin.pass.cpp b/libcxx/test/std/containers/views/span.iterators/rbegin.pass.cpp
index 66e1d5ebf96bc2ae0ec7d3818cecb153a49959a9..fc7d3c8e006879822464d7afbd0547fff05cd429 100644
--- a/libcxx/test/std/containers/views/span.iterators/rbegin.pass.cpp
+++ b/libcxx/test/std/containers/views/span.iterators/rbegin.pass.cpp
@@ -71,7 +71,7 @@ constexpr int iArr1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9};
           int iArr2[] = {10, 11, 12, 13, 14, 15, 16, 17, 18, 19};
 
 
-int main()
+int main(int, char**)
 {
     static_assert(testConstexprSpan(std::span<int>()),            "");
     static_assert(testConstexprSpan(std::span<long>()),           "");
@@ -113,4 +113,6 @@ int main()
     std::string s;
     testRuntimeSpan(std::span<std::string>(&s, static_cast<std::ptrdiff_t>(0)));
     testRuntimeSpan(std::span<std::string>(&s, 1));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.iterators/rend.pass.cpp b/libcxx/test/std/containers/views/span.iterators/rend.pass.cpp
index 7c53cb0becddb66c90d003ac170918a08e1e0ab1..056fe2a7d2bc7500bdfe0ac3ef35d68630cd22c1 100644
--- a/libcxx/test/std/containers/views/span.iterators/rend.pass.cpp
+++ b/libcxx/test/std/containers/views/span.iterators/rend.pass.cpp
@@ -72,7 +72,7 @@ constexpr int iArr1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9};
           int iArr2[] = {10, 11, 12, 13, 14, 15, 16, 17, 18, 19};
 
 
-int main()
+int main(int, char**)
 {
     static_assert(testConstexprSpan(std::span<int>()),            "");
     static_assert(testConstexprSpan(std::span<long>()),           "");
@@ -114,4 +114,6 @@ int main()
     std::string s;
     testRuntimeSpan(std::span<std::string>(&s, (std::ptrdiff_t) 0));
     testRuntimeSpan(std::span<std::string>(&s, 1));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.objectrep/as_bytes.pass.cpp b/libcxx/test/std/containers/views/span.objectrep/as_bytes.pass.cpp
index 989b6dc5cb69ff98ec38da918e971ac07b89985a..3e6a7d79ffd1d6e9f8750ebdd1b27abe1628c16f 100644
--- a/libcxx/test/std/containers/views/span.objectrep/as_bytes.pass.cpp
+++ b/libcxx/test/std/containers/views/span.objectrep/as_bytes.pass.cpp
@@ -45,7 +45,7 @@ void testRuntimeSpan(Span sp)
 struct A{};
 int iArr2[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9};
 
-int main ()
+int main(int, char**)
 {
     testRuntimeSpan(std::span<int>        ());
     testRuntimeSpan(std::span<long>       ());
@@ -74,4 +74,6 @@ int main ()
     std::string s;
     testRuntimeSpan(std::span<std::string>(&s, (std::ptrdiff_t) 0));
     testRuntimeSpan(std::span<std::string>(&s, 1));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.objectrep/as_writeable_bytes.fail.cpp b/libcxx/test/std/containers/views/span.objectrep/as_writeable_bytes.fail.cpp
index 9b0034b9b58a9a7b1715f715ab9fd5a244145ac2..b987edb30a52e91fe4285d9b41211d514300905c 100644
--- a/libcxx/test/std/containers/views/span.objectrep/as_writeable_bytes.fail.cpp
+++ b/libcxx/test/std/containers/views/span.objectrep/as_writeable_bytes.fail.cpp
@@ -28,7 +28,7 @@ const int iArr2[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9};
 
 struct A {};
 
-int main ()
+int main(int, char**)
 {
     std::as_writeable_bytes(std::span<const int>());            // expected-error {{no matching function for call to 'as_writeable_bytes'}}
     std::as_writeable_bytes(std::span<const long>());           // expected-error {{no matching function for call to 'as_writeable_bytes'}}
@@ -44,4 +44,6 @@ int main ()
 
     std::as_writeable_bytes(std::span<const int>   (iArr2, 1));     // expected-error {{no matching function for call to 'as_writeable_bytes'}}
     std::as_writeable_bytes(std::span<const int, 1>(iArr2 + 5, 1)); // expected-error {{no matching function for call to 'as_writeable_bytes'}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.objectrep/as_writeable_bytes.pass.cpp b/libcxx/test/std/containers/views/span.objectrep/as_writeable_bytes.pass.cpp
index 6538a59465a7676067ced07b02a3f56fe51cb762..96bb40ec49b553e0da106c657d1f7985544d077b 100644
--- a/libcxx/test/std/containers/views/span.objectrep/as_writeable_bytes.pass.cpp
+++ b/libcxx/test/std/containers/views/span.objectrep/as_writeable_bytes.pass.cpp
@@ -45,7 +45,7 @@ void testRuntimeSpan(Span sp)
 struct A{};
 int iArr2[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9};
 
-int main ()
+int main(int, char**)
 {
     testRuntimeSpan(std::span<int>        ());
     testRuntimeSpan(std::span<long>       ());
@@ -74,4 +74,6 @@ int main ()
     std::string s;
     testRuntimeSpan(std::span<std::string>(&s, (std::ptrdiff_t) 0));
     testRuntimeSpan(std::span<std::string>(&s, 1));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.obs/empty.pass.cpp b/libcxx/test/std/containers/views/span.obs/empty.pass.cpp
index e0cdb141b1e1a1364b0937a465e2aa387c328773..9db8c8ab71c057ea0a2e303b681f9b945608d8ef 100644
--- a/libcxx/test/std/containers/views/span.obs/empty.pass.cpp
+++ b/libcxx/test/std/containers/views/span.obs/empty.pass.cpp
@@ -24,7 +24,7 @@ struct A{};
 constexpr int iArr1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9};
           int iArr2[] = {10, 11, 12, 13, 14, 15, 16, 17, 18, 19};
 
-int main ()
+int main(int, char**)
 {
     static_assert( noexcept(std::span<int>   ().empty()), "");
     static_assert( noexcept(std::span<int, 0>().empty()), "");
@@ -69,4 +69,6 @@ int main ()
     std::string s;
     assert( ((std::span<std::string>(&s, (std::ptrdiff_t) 0)).empty()));
     assert(!((std::span<std::string>(&s, 1).empty())));
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.obs/size.pass.cpp b/libcxx/test/std/containers/views/span.obs/size.pass.cpp
index 0dc1dd268f8df5b99a7cca99bb86ff37b1bdf075..f1dbc1fd99e0aa7219f0910d6adaa1b2fadc8f8d 100644
--- a/libcxx/test/std/containers/views/span.obs/size.pass.cpp
+++ b/libcxx/test/std/containers/views/span.obs/size.pass.cpp
@@ -40,7 +40,7 @@ struct A{};
 constexpr int iArr1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9};
           int iArr2[] = {10, 11, 12, 13, 14, 15, 16, 17, 18, 19};
 
-int main ()
+int main(int, char**)
 {
     static_assert(testConstexprSpan(std::span<int>(), 0),            "");
     static_assert(testConstexprSpan(std::span<long>(), 0),           "");
@@ -87,4 +87,6 @@ int main ()
     std::string s;
     testRuntimeSpan(std::span<std::string>(&s, (std::ptrdiff_t) 0), 0);
     testRuntimeSpan(std::span<std::string>(&s, 1), 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.obs/size_bytes.pass.cpp b/libcxx/test/std/containers/views/span.obs/size_bytes.pass.cpp
index fa26a408f30ac0268fe56a6fa645a97ec3dd770f..1d423527cd05cd78e63f27934d1b41cb82df0938 100644
--- a/libcxx/test/std/containers/views/span.obs/size_bytes.pass.cpp
+++ b/libcxx/test/std/containers/views/span.obs/size_bytes.pass.cpp
@@ -41,7 +41,7 @@ struct A{};
 constexpr int iArr1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9};
           int iArr2[] = {10, 11, 12, 13, 14, 15, 16, 17, 18, 19};
 
-int main ()
+int main(int, char**)
 {
     static_assert(testConstexprSpan(std::span<int>(), 0),            "");
     static_assert(testConstexprSpan(std::span<long>(), 0),           "");
@@ -88,4 +88,6 @@ int main ()
     std::string s;
     testRuntimeSpan(std::span<std::string>(&s, (std::ptrdiff_t) 0), 0);
     testRuntimeSpan(std::span<std::string>(&s, 1), 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.sub/first.pass.cpp b/libcxx/test/std/containers/views/span.sub/first.pass.cpp
index 7d66884280ac3b45b613a6e96ea21e6630f982f4..f9da9fdc233878b100714640e3229543c8381644 100644
--- a/libcxx/test/std/containers/views/span.sub/first.pass.cpp
+++ b/libcxx/test/std/containers/views/span.sub/first.pass.cpp
@@ -68,7 +68,7 @@ constexpr int carr1[] = {1,2,3,4};
           int   arr[] = {5,6,7};
 std::string   sarr [] = { "ABC", "DEF", "GHI", "JKL", "MNO"};
 
-int main ()
+int main(int, char**)
 {
     {
     using Sp = std::span<const int>;
@@ -132,4 +132,6 @@ int main ()
     testRuntimeSpan<Sp, 4>(Sp{sarr});
     testRuntimeSpan<Sp, 5>(Sp{sarr});
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.sub/last.pass.cpp b/libcxx/test/std/containers/views/span.sub/last.pass.cpp
index 1715560477601c19ad0927e0eed73b106c3cab1d..e0a399ff9cd3c13555e8fc6ec67c446aa87be4b4 100644
--- a/libcxx/test/std/containers/views/span.sub/last.pass.cpp
+++ b/libcxx/test/std/containers/views/span.sub/last.pass.cpp
@@ -68,7 +68,7 @@ constexpr int carr1[] = {1,2,3,4};
           int   arr[] = {5,6,7};
 std::string   sarr [] = { "ABC", "DEF", "GHI", "JKL", "MNO"};
 
-int main ()
+int main(int, char**)
 {
     {
     using Sp = std::span<const int>;
@@ -132,4 +132,6 @@ int main ()
     testRuntimeSpan<Sp, 4>(Sp{sarr});
     testRuntimeSpan<Sp, 5>(Sp{sarr});
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/span.sub/subspan.pass.cpp b/libcxx/test/std/containers/views/span.sub/subspan.pass.cpp
index 22446adbbd6ba358bdae75f0d15e156da999de67..9cb7310934720b850ae243f930561e9e300e118f 100644
--- a/libcxx/test/std/containers/views/span.sub/subspan.pass.cpp
+++ b/libcxx/test/std/containers/views/span.sub/subspan.pass.cpp
@@ -106,7 +106,7 @@ void testRuntimeSpan(Span sp)
 constexpr int carr1[] = {1,2,3,4};
           int  arr1[] = {5,6,7};
 
-int main ()
+int main(int, char**)
 {
     {
     using Sp = std::span<const int>;
@@ -206,4 +206,6 @@ int main ()
     testRuntimeSpan<Sp, 2>(Sp{arr1});
     testRuntimeSpan<Sp, 3>(Sp{arr1});
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/views/types.pass.cpp b/libcxx/test/std/containers/views/types.pass.cpp
index e8ddbed161f779b179e8b30675b980190eeb964c..ac6f47fa8e5a63555fff7d2db3f8fafc980abec5 100644
--- a/libcxx/test/std/containers/views/types.pass.cpp
+++ b/libcxx/test/std/containers/views/types.pass.cpp
@@ -96,11 +96,13 @@ void test()
 
 struct A{};
 
-int main ()
+int main(int, char**)
 {
     test<int>();
     test<long>();
     test<double>();
     test<std::string>();
     test<A>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/assignment.fail.cpp b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/assignment.fail.cpp
index 1b2d9043fbad025b3b0785ccaf188d36594601c2..2fa102e2783745d540af242caecbe13391582b8d 100644
--- a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/assignment.fail.cpp
+++ b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/assignment.fail.cpp
@@ -37,7 +37,9 @@ test()
     assert(A::count == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/assignment.pass.cpp b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/assignment.pass.cpp
index a8899e103fd7bd8d3bc5ea61c10b21871082941b..31eb1f67db7eb8be4c390eff8f9783425e6ebe85 100644
--- a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/assignment.pass.cpp
+++ b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/assignment.pass.cpp
@@ -39,7 +39,9 @@ test()
     assert(A::count == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/convert.fail.cpp b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/convert.fail.cpp
index 9e7505acdd7143e0cbea6d9cfea4372b0d1797f9..2a7fe6640b286509c61937da4b1754b951ba0450 100644
--- a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/convert.fail.cpp
+++ b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/convert.fail.cpp
@@ -33,7 +33,9 @@ test()
     assert(B::count == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/convert.pass.cpp b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/convert.pass.cpp
index eccfad4cb5f8a792d02764b9966641115d9de563..3d574de342a9b3df646109040880b0ed1723c411 100644
--- a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/convert.pass.cpp
+++ b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/convert.pass.cpp
@@ -35,7 +35,9 @@ test()
     assert(B::count == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/convert_assignment.fail.cpp b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/convert_assignment.fail.cpp
index c3abdf01062c338bb803ec2c31bd36c1b122f277..23f6a19995bc188c11904f06625416390d7f5cd0 100644
--- a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/convert_assignment.fail.cpp
+++ b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/convert_assignment.fail.cpp
@@ -40,7 +40,9 @@ test()
     assert(B::count == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/convert_assignment.pass.cpp b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/convert_assignment.pass.cpp
index 5704f8db076bea86512022b9a6cf28a45c0d9a93..dc363c1e9a759d6bd0402c952c8f9d159856344e 100644
--- a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/convert_assignment.pass.cpp
+++ b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/convert_assignment.pass.cpp
@@ -42,7 +42,9 @@ test()
     assert(B::count == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/copy.fail.cpp b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/copy.fail.cpp
index 9efb9cdb6ee4bdaf8f9afbf96b4577d5f2ae7f1e..3684da493529ee6b652c50b5a1cf11b06fa8a44c 100644
--- a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/copy.fail.cpp
+++ b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/copy.fail.cpp
@@ -31,7 +31,9 @@ test()
     assert(A::count == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/copy.pass.cpp b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/copy.pass.cpp
index 6c9c476cd19fe4254d145c401ea1b82d20367343..0e674f21a348d679534fae5f3d60a40da77d74fe 100644
--- a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/copy.pass.cpp
+++ b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/copy.pass.cpp
@@ -33,7 +33,9 @@ test()
     assert(A::count == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/explicit.fail.cpp b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/explicit.fail.cpp
index 7e75911ffa7bd2aa514b85bfb60a9e019fb15c62..e91abaf5a1bf24fc872bf16b78b3a69cee1acce5 100644
--- a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/explicit.fail.cpp
+++ b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/explicit.fail.cpp
@@ -33,7 +33,9 @@ test()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/pointer.pass.cpp b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/pointer.pass.cpp
index 400126e4ab42c2471f110130801a9aebe2b77b80..7423c3b73f3c5913f0d236b2ba62f6cc86fd7d33 100644
--- a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/pointer.pass.cpp
+++ b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.cons/pointer.pass.cpp
@@ -35,7 +35,9 @@ test()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.conv/assign_from_auto_ptr_ref.pass.cpp b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.conv/assign_from_auto_ptr_ref.pass.cpp
index 0b5b9c5da0b214b125f33f4c7aa35c6755d95bb7..0486e02fb83cbbb3751e7e3a7678c9cf99341367 100644
--- a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.conv/assign_from_auto_ptr_ref.pass.cpp
+++ b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.conv/assign_from_auto_ptr_ref.pass.cpp
@@ -35,7 +35,9 @@ test()
     assert(A::count == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.conv/convert_from_auto_ptr_ref.pass.cpp b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.conv/convert_from_auto_ptr_ref.pass.cpp
index 2e08decfa7d90ed82c2401919d303565d4815614..7dd37f76026e54c2273e6c789143c8aca4e0f2a9 100644
--- a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.conv/convert_from_auto_ptr_ref.pass.cpp
+++ b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.conv/convert_from_auto_ptr_ref.pass.cpp
@@ -34,7 +34,9 @@ test()
     assert(B::count == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.conv/convert_to_auto_ptr.pass.cpp b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.conv/convert_to_auto_ptr.pass.cpp
index 554ce3165b850894af570304fd0f5683d267bcf1..809f6b37e179c6585e32be12e7b10e0249896bbe 100644
--- a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.conv/convert_to_auto_ptr.pass.cpp
+++ b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.conv/convert_to_auto_ptr.pass.cpp
@@ -31,7 +31,9 @@ test()
     std::auto_ptr<A> ap2(source());
 }
 
-int main()
+int main(int, char**)
 {
     test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.conv/convert_to_auto_ptr_ref.pass.cpp b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.conv/convert_to_auto_ptr_ref.pass.cpp
index bcb7d61c9858171c74e29a03ade92a57351e618f..a75f134923635c57b492ccff24b16fcd689eb93b 100644
--- a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.conv/convert_to_auto_ptr_ref.pass.cpp
+++ b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.conv/convert_to_auto_ptr_ref.pass.cpp
@@ -32,7 +32,9 @@ test()
     delete p1;
 }
 
-int main()
+int main(int, char**)
 {
     test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.members/arrow.pass.cpp b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.members/arrow.pass.cpp
index c10beec7967d24de3c94c8ec0bef0b0e907dc9e4..7878f50f7a9d7772defbf8f21cab7e66328ed100 100644
--- a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.members/arrow.pass.cpp
+++ b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.members/arrow.pass.cpp
@@ -32,7 +32,9 @@ test()
     assert(A::count == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.members/deref.pass.cpp b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.members/deref.pass.cpp
index 271b4ffb496a2628c569fcdabaa3178e388c92ee..1e41c8a9daba0ff7d76e5eea2f618ab2e3c8fd5c 100644
--- a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.members/deref.pass.cpp
+++ b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.members/deref.pass.cpp
@@ -32,7 +32,9 @@ test()
     assert(A::count == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.members/release.pass.cpp b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.members/release.pass.cpp
index 2cd0faf2736cbb0d7476d692ee3f6de3f6584980..61b6bbcc6925caf05b6191977d3d4a92e7ca073a 100644
--- a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.members/release.pass.cpp
+++ b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.members/release.pass.cpp
@@ -33,7 +33,9 @@ test()
     assert(A::count == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.members/reset.pass.cpp b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.members/reset.pass.cpp
index c74cabf79f30fe400f85b1db4525dd56f111020f..d2ebd5668e91bf4123cae4e73a8cd945ff08f1b2 100644
--- a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.members/reset.pass.cpp
+++ b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/auto.ptr.members/reset.pass.cpp
@@ -49,7 +49,9 @@ test()
     assert(A::count == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/element_type.pass.cpp b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/element_type.pass.cpp
index 36e59dd0fa58a665dad23f1b69879e8e88e54206..a4dac761526de59d1512fee36d7e598e08073ae4 100644
--- a/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/element_type.pass.cpp
+++ b/libcxx/test/std/depr/depr.auto.ptr/auto.ptr/element_type.pass.cpp
@@ -30,9 +30,11 @@ test()
     ((void)p);
 }
 
-int main()
+int main(int, char**)
 {
     test<int>();
     test<double>();
     test<void>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.auto.ptr/nothing_to_do.pass.cpp b/libcxx/test/std/depr/depr.auto.ptr/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/depr/depr.auto.ptr/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/depr/depr.auto.ptr/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.c.headers/assert_h.pass.cpp b/libcxx/test/std/depr/depr.c.headers/assert_h.pass.cpp
index aee59570a8c04e34a79ed0d9d3654219c0001eef..d680f33efccb9913bbbd2fcff58e4aa3d3e5b7b4 100644
--- a/libcxx/test/std/depr/depr.c.headers/assert_h.pass.cpp
+++ b/libcxx/test/std/depr/depr.c.headers/assert_h.pass.cpp
@@ -14,6 +14,8 @@
 #error assert not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.c.headers/ciso646.pass.cpp b/libcxx/test/std/depr/depr.c.headers/ciso646.pass.cpp
index 2f962bc8b6e8e222e014876c36a27118ed3ddb3f..3eb4064e69e1fc53d61e73406984cdabe32abc9c 100644
--- a/libcxx/test/std/depr/depr.c.headers/ciso646.pass.cpp
+++ b/libcxx/test/std/depr/depr.c.headers/ciso646.pass.cpp
@@ -10,6 +10,8 @@
 
 #include <ciso646>
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.c.headers/complex.h.pass.cpp b/libcxx/test/std/depr/depr.c.headers/complex.h.pass.cpp
index 6502bb669651905694cc89e150f0d7f900ec9d07..d92ddb67b0e8d10695c8268f6404ea42400276fe 100644
--- a/libcxx/test/std/depr/depr.c.headers/complex.h.pass.cpp
+++ b/libcxx/test/std/depr/depr.c.headers/complex.h.pass.cpp
@@ -10,8 +10,10 @@
 
 #include <complex.h>
 
-int main()
+int main(int, char**)
 {
     std::complex<double> d;
     (void)d;
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.c.headers/ctype_h.pass.cpp b/libcxx/test/std/depr/depr.c.headers/ctype_h.pass.cpp
index 7c7c83a836710f3f76ceaf5ed683fa5b5afe1dd9..61b539d40939532c7fe0b3d7d80b12fdaf5b14e2 100644
--- a/libcxx/test/std/depr/depr.c.headers/ctype_h.pass.cpp
+++ b/libcxx/test/std/depr/depr.c.headers/ctype_h.pass.cpp
@@ -68,7 +68,7 @@
 #error toupper defined
 #endif
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<decltype(isalnum(0)), int>::value), "");
     static_assert((std::is_same<decltype(isalpha(0)), int>::value), "");
@@ -99,4 +99,6 @@ int main()
     assert(isxdigit('a'));
     assert(tolower('A') == 'a');
     assert(toupper('a') == 'A');
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.c.headers/errno_h.pass.cpp b/libcxx/test/std/depr/depr.c.headers/errno_h.pass.cpp
index 51ad3fe7c9f0065de47340ddd0c36f05a2b42f03..985cdc7f5c4d22e193817afcd1ba9f49a5be86cf 100644
--- a/libcxx/test/std/depr/depr.c.headers/errno_h.pass.cpp
+++ b/libcxx/test/std/depr/depr.c.headers/errno_h.pass.cpp
@@ -27,6 +27,8 @@
 #error errno not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.c.headers/fenv_h.pass.cpp b/libcxx/test/std/depr/depr.c.headers/fenv_h.pass.cpp
index b6c2549b5cbd4c243245e2cc5f10e89e2083cfc5..3a6f63c3fc34caf7411f8fa4f825c2e4f8362105 100644
--- a/libcxx/test/std/depr/depr.c.headers/fenv_h.pass.cpp
+++ b/libcxx/test/std/depr/depr.c.headers/fenv_h.pass.cpp
@@ -57,7 +57,7 @@
 #error FE_DFL_ENV not defined
 #endif
 
-int main()
+int main(int, char**)
 {
     fenv_t fenv = {};
     fexcept_t fex = 0;
@@ -72,4 +72,6 @@ int main()
     static_assert((std::is_same<decltype(feholdexcept(&fenv)), int>::value), "");
     static_assert((std::is_same<decltype(fesetenv(&fenv)), int>::value), "");
     static_assert((std::is_same<decltype(feupdateenv(&fenv)), int>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.c.headers/float_h.pass.cpp b/libcxx/test/std/depr/depr.c.headers/float_h.pass.cpp
index 3e73b385de7a3437eb5fcf57bba78be45d07d8e1..779fbc66f5d020c7371eec308e88e5dd5e47ce74 100644
--- a/libcxx/test/std/depr/depr.c.headers/float_h.pass.cpp
+++ b/libcxx/test/std/depr/depr.c.headers/float_h.pass.cpp
@@ -178,6 +178,8 @@
 #endif
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.c.headers/inttypes_h.pass.cpp b/libcxx/test/std/depr/depr.c.headers/inttypes_h.pass.cpp
index 6db3a42f1842ab5c95563ddde07acff9b90d0e3c..a088733119e94dac3f87a47895a38e0d80b843b0 100644
--- a/libcxx/test/std/depr/depr.c.headers/inttypes_h.pass.cpp
+++ b/libcxx/test/std/depr/depr.c.headers/inttypes_h.pass.cpp
@@ -877,7 +877,7 @@ template <class T> void test()
     ((void)t); // Prevent unused warning
 }
 
-int main()
+int main(int, char**)
 {
     test<int8_t >();
     test<int16_t>();
@@ -927,4 +927,6 @@ int main()
     static_assert((std::is_same<decltype(strtoumax("", (char**)0, 0)), uintmax_t>::value), "");
     static_assert((std::is_same<decltype(wcstoimax(L"", (wchar_t**)0, 0)), intmax_t>::value), "");
     static_assert((std::is_same<decltype(wcstoumax(L"", (wchar_t**)0, 0)), uintmax_t>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.c.headers/iso646_h.pass.cpp b/libcxx/test/std/depr/depr.c.headers/iso646_h.pass.cpp
index dee560858a0e95be1645739f1df7c7b9dfd7d68d..77ca126278d91d6d4e7ec1531386fafe5c2e7c68 100644
--- a/libcxx/test/std/depr/depr.c.headers/iso646_h.pass.cpp
+++ b/libcxx/test/std/depr/depr.c.headers/iso646_h.pass.cpp
@@ -10,7 +10,9 @@
 
 #include <iso646.h>
 
-int main()
+int main(int, char**)
 {
     // Nothing to test
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.c.headers/limits_h.pass.cpp b/libcxx/test/std/depr/depr.c.headers/limits_h.pass.cpp
index a8ad39215bee07aa2de162688067297b058a3fb1..5dba10edfb7e1e1df205276925a57790526b86d5 100644
--- a/libcxx/test/std/depr/depr.c.headers/limits_h.pass.cpp
+++ b/libcxx/test/std/depr/depr.c.headers/limits_h.pass.cpp
@@ -86,6 +86,8 @@
 #error ULLONG_MAX not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.c.headers/locale_h.pass.cpp b/libcxx/test/std/depr/depr.c.headers/locale_h.pass.cpp
index 9774dd6e83d0102e6a095923f2022147abc6a703..fd2419bb707572853b5a52199783b7dc13533f52 100644
--- a/libcxx/test/std/depr/depr.c.headers/locale_h.pass.cpp
+++ b/libcxx/test/std/depr/depr.c.headers/locale_h.pass.cpp
@@ -39,9 +39,11 @@
 #error NULL not defined
 #endif
 
-int main()
+int main(int, char**)
 {
     lconv lc; ((void)lc);
     static_assert((std::is_same<decltype(setlocale(0, "")), char*>::value), "");
     static_assert((std::is_same<decltype(localeconv()), lconv*>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.c.headers/math_h.pass.cpp b/libcxx/test/std/depr/depr.c.headers/math_h.pass.cpp
index 5625971062550e853d6dfc5dbe15e9ebf0aad76a..b0b6c0cb3249fccad35a3e29f21f9f21ea12be4b 100644
--- a/libcxx/test/std/depr/depr.c.headers/math_h.pass.cpp
+++ b/libcxx/test/std/depr/depr.c.headers/math_h.pass.cpp
@@ -1463,7 +1463,7 @@ void test_trunc()
     assert(trunc(1) == 1);
 }
 
-int main()
+int main(int, char**)
 {
     test_abs();
     test_acos();
@@ -1535,4 +1535,6 @@ int main()
     test_scalbn();
     test_tgamma();
     test_trunc();
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.c.headers/setjmp_h.pass.cpp b/libcxx/test/std/depr/depr.c.headers/setjmp_h.pass.cpp
index 3c8584b1b2f24379b733f180ba7d90ac5d87e89b..1878f4f847078b530fc8e0d0b47ba860129d1926 100644
--- a/libcxx/test/std/depr/depr.c.headers/setjmp_h.pass.cpp
+++ b/libcxx/test/std/depr/depr.c.headers/setjmp_h.pass.cpp
@@ -15,10 +15,12 @@
 #error setjmp not defined
 #endif
 
-int main()
+int main(int, char**)
 {
     jmp_buf jb;
     ((void)jb); // Prevent unused warning
     static_assert((std::is_same<decltype(longjmp(jb, 0)), void>::value),
                   "std::is_same<decltype(longjmp(jb, 0)), void>::value");
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.c.headers/signal_h.pass.cpp b/libcxx/test/std/depr/depr.c.headers/signal_h.pass.cpp
index e2fc456e44ca4ac4247c3cdf34034400cd4220b9..463d670ba1eba209cc5ee8135cba46e4961ff77a 100644
--- a/libcxx/test/std/depr/depr.c.headers/signal_h.pass.cpp
+++ b/libcxx/test/std/depr/depr.c.headers/signal_h.pass.cpp
@@ -47,10 +47,12 @@
 #error SIGTERM not defined
 #endif
 
-int main()
+int main(int, char**)
 {
     sig_atomic_t sig; ((void)sig);
     typedef void (*func)(int);
     static_assert((std::is_same<decltype(signal(0, (func)0)), func>::value), "");
     static_assert((std::is_same<decltype(raise(0)), int>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.c.headers/stdarg_h.pass.cpp b/libcxx/test/std/depr/depr.c.headers/stdarg_h.pass.cpp
index a336fe59f4ba5a09c0a64d79a2984d8655fa287b..feb9c4a460f38e4c93ea4c374ec572c865057e35 100644
--- a/libcxx/test/std/depr/depr.c.headers/stdarg_h.pass.cpp
+++ b/libcxx/test/std/depr/depr.c.headers/stdarg_h.pass.cpp
@@ -30,8 +30,10 @@
 #error va_start not defined
 #endif
 
-int main()
+int main(int, char**)
 {
     va_list va;
     ((void)va);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.c.headers/stdbool_h.pass.cpp b/libcxx/test/std/depr/depr.c.headers/stdbool_h.pass.cpp
index 38dfc6d8496e5bef28a3a86a79f963481bb7153b..132ad9c5cd964a0b68af8ba1c557c096d63a8e24 100644
--- a/libcxx/test/std/depr/depr.c.headers/stdbool_h.pass.cpp
+++ b/libcxx/test/std/depr/depr.c.headers/stdbool_h.pass.cpp
@@ -26,6 +26,8 @@
 #error false should not be defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.c.headers/stddef_h.pass.cpp b/libcxx/test/std/depr/depr.c.headers/stddef_h.pass.cpp
index 8c420de52e36a052ad30b15e0d42783ee128a5dd..c54c976ee0946fc7161b44dc6d53fcc6585c649f 100644
--- a/libcxx/test/std/depr/depr.c.headers/stddef_h.pass.cpp
+++ b/libcxx/test/std/depr/depr.c.headers/stddef_h.pass.cpp
@@ -22,7 +22,7 @@
 #error offsetof not defined
 #endif
 
-int main()
+int main(int, char**)
 {
     void *p = NULL;
     assert(!p);
@@ -65,4 +65,6 @@ int main()
                   std::alignment_of<void*>::value,
                   "std::alignment_of<max_align_t>::value >= "
                   "std::alignment_of<void*>::value");
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.c.headers/stdint_h.pass.cpp b/libcxx/test/std/depr/depr.c.headers/stdint_h.pass.cpp
index e031e21036d5c08ed4d8882363750334f5c04ad8..68efe7992af932af6642a433df1ccf9f05fec592 100644
--- a/libcxx/test/std/depr/depr.c.headers/stdint_h.pass.cpp
+++ b/libcxx/test/std/depr/depr.c.headers/stdint_h.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     // typedef int8_t
     static_assert(sizeof(int8_t)*CHAR_BIT == 8,
@@ -287,4 +287,6 @@ int main()
 #ifndef UINTMAX_C
 #error UINTMAX_C not defined
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.c.headers/stdio_h.pass.cpp b/libcxx/test/std/depr/depr.c.headers/stdio_h.pass.cpp
index b60279696c08e77c88034d24996999831a9328fe..97ea0d41519b6a5f7f045b35a66abd90a9091a3d 100644
--- a/libcxx/test/std/depr/depr.c.headers/stdio_h.pass.cpp
+++ b/libcxx/test/std/depr/depr.c.headers/stdio_h.pass.cpp
@@ -103,7 +103,7 @@
 #pragma GCC diagnostic ignored "-Wdeprecated-declarations" // for tmpnam
 #endif
 
-int main()
+int main(int, char**)
 {
     FILE* fp = 0;
     fpos_t fpos = fpos_t();
@@ -165,4 +165,6 @@ int main()
     static_assert((std::is_same<decltype(feof(fp)), int>::value), "");
     static_assert((std::is_same<decltype(ferror(fp)), int>::value), "");
     static_assert((std::is_same<decltype(perror("")), void>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.c.headers/stdlib_h.pass.cpp b/libcxx/test/std/depr/depr.c.headers/stdlib_h.pass.cpp
index c035cf046a722662063d1aa4b6f98a83ed3dcec2..4c0218d6ef6aab999f06f0f11748aab17b1dd84d 100644
--- a/libcxx/test/std/depr/depr.c.headers/stdlib_h.pass.cpp
+++ b/libcxx/test/std/depr/depr.c.headers/stdlib_h.pass.cpp
@@ -63,7 +63,7 @@
 #error RAND_MAX not defined
 #endif
 
-int main()
+int main(int, char**)
 {
     size_t s = 0; ((void)s);
     div_t d; ((void)d);
@@ -116,4 +116,6 @@ int main()
     static_assert((std::is_same<decltype(wctomb(pc,L' ')), int>::value), "");
     static_assert((std::is_same<decltype(mbstowcs(pw,"",0)), size_t>::value), "");
     static_assert((std::is_same<decltype(wcstombs(pc,pwc,0)), size_t>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.c.headers/string_h.pass.cpp b/libcxx/test/std/depr/depr.c.headers/string_h.pass.cpp
index 62c552b9bec23b35b687d66a652f71a2783798bb..8ed1513b356597a3b5e49bfc9aee14d12f864148 100644
--- a/libcxx/test/std/depr/depr.c.headers/string_h.pass.cpp
+++ b/libcxx/test/std/depr/depr.c.headers/string_h.pass.cpp
@@ -15,7 +15,7 @@
 #error NULL not defined
 #endif
 
-int main()
+int main(int, char**)
 {
     size_t s = 0;
     void* vp = 0;
@@ -57,4 +57,6 @@ int main()
     static_assert((std::is_same<decltype(strstr(cpc, cpc)), const char*>::value), "");
     static_assert((std::is_same<decltype(memchr(vpc, 0, s)), const void*>::value), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.c.headers/tgmath_h.pass.cpp b/libcxx/test/std/depr/depr.c.headers/tgmath_h.pass.cpp
index e9c480605086bb3b8d444be89bf08865bf5b07e9..28cf93ada0aba0ad87c3780909ec22147f41160c 100644
--- a/libcxx/test/std/depr/depr.c.headers/tgmath_h.pass.cpp
+++ b/libcxx/test/std/depr/depr.c.headers/tgmath_h.pass.cpp
@@ -10,10 +10,12 @@
 
 #include <tgmath.h>
 
-int main()
+int main(int, char**)
 {
     std::complex<double> cd;
     (void)cd;
     double x = sin(1.0);
     (void)x; // to placate scan-build
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.c.headers/time_h.pass.cpp b/libcxx/test/std/depr/depr.c.headers/time_h.pass.cpp
index eb9565128eba8b01b21a19e124cf5766e42c035a..5c2cc57bc6907c8edc63380e69b7c8c8a11dbda2 100644
--- a/libcxx/test/std/depr/depr.c.headers/time_h.pass.cpp
+++ b/libcxx/test/std/depr/depr.c.headers/time_h.pass.cpp
@@ -19,7 +19,7 @@
 #error CLOCKS_PER_SEC not defined
 #endif
 
-int main()
+int main(int, char**)
 {
     clock_t c = 0; ((void)c);
     size_t s = 0;
@@ -36,4 +36,6 @@ int main()
     char* c1 = 0;
     const char* c2 = 0;
     static_assert((std::is_same<decltype(strftime(c1,s,c2,&tmv)), size_t>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.c.headers/uchar_h.pass.cpp b/libcxx/test/std/depr/depr.c.headers/uchar_h.pass.cpp
index bff39d2c8554ff54da799fd8e90c08daa48aaf26..cddf7a284a3ac38ff3bd967552a301bc5c89faa1 100644
--- a/libcxx/test/std/depr/depr.c.headers/uchar_h.pass.cpp
+++ b/libcxx/test/std/depr/depr.c.headers/uchar_h.pass.cpp
@@ -15,6 +15,8 @@
 
 #include <uchar.h>
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.c.headers/wchar_h.pass.cpp b/libcxx/test/std/depr/depr.c.headers/wchar_h.pass.cpp
index 6072159952c471403bacb5531fdbd1d93271a26a..b964ea76f94242c1e414da36c077d729036c3381 100644
--- a/libcxx/test/std/depr/depr.c.headers/wchar_h.pass.cpp
+++ b/libcxx/test/std/depr/depr.c.headers/wchar_h.pass.cpp
@@ -28,7 +28,7 @@
 #error WEOF not defined
 #endif
 
-int main()
+int main(int, char**)
 {
 // mbstate_t comes from the underlying C library; it is defined (in C99) as:
 //    a complete object type other than an array type that can hold the conversion
@@ -126,4 +126,6 @@ int main()
     static_assert((std::is_same<decltype(vwprintf(L"", va)), int>::value), "");
     static_assert((std::is_same<decltype(wprintf(L"")), int>::value), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.c.headers/wctype_h.pass.cpp b/libcxx/test/std/depr/depr.c.headers/wctype_h.pass.cpp
index f4dc1bf4f7a8dbab5c4b1849c8d5234ade0192c4..1774a7f0897e6de4de7d7820ff0c6f97e1e5f13d 100644
--- a/libcxx/test/std/depr/depr.c.headers/wctype_h.pass.cpp
+++ b/libcxx/test/std/depr/depr.c.headers/wctype_h.pass.cpp
@@ -87,7 +87,7 @@
 #error wctrans defined
 #endif
 
-int main()
+int main(int, char**)
 {
     wint_t w = 0;
     wctrans_t wctr = 0;
@@ -110,4 +110,6 @@ int main()
     static_assert((std::is_same<decltype(towupper(w)), wint_t>::value), "");
     static_assert((std::is_same<decltype(towctrans(w, wctr)), wint_t>::value), "");
     static_assert((std::is_same<decltype(wctrans("")), wctrans_t>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/pointer_to_binary_function.cxx1z.fail.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/pointer_to_binary_function.cxx1z.fail.cpp
index 062bbaee8da01780bfbce0c805dd0a7d576659dc..feb345b9ae57b33667c77809785583b1320f119c 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/pointer_to_binary_function.cxx1z.fail.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/pointer_to_binary_function.cxx1z.fail.cpp
@@ -18,7 +18,9 @@
 
 double binary_f(int i, short j) {return i - j + .75;}
 
-int main()
+int main(int, char**)
 {
     typedef std::pointer_to_binary_function<int, short, double> F;
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/pointer_to_binary_function.pass.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/pointer_to_binary_function.pass.cpp
index 8d099e52ca7bb6f3ce0534ee76f7336adf09da13..53df5f34832cb7f3857bb95d5c0317292756a452 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/pointer_to_binary_function.pass.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/pointer_to_binary_function.pass.cpp
@@ -17,10 +17,12 @@
 
 double binary_f(int i, short j) {return i - j + .75;}
 
-int main()
+int main(int, char**)
 {
     typedef std::pointer_to_binary_function<int, short, double> F;
     static_assert((std::is_base_of<std::binary_function<int, short, double>, F>::value), "");
     const F f(binary_f);
     assert(f(36, 27) == 9.75);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/pointer_to_unary_function.cxx1z.fail.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/pointer_to_unary_function.cxx1z.fail.cpp
index cc3bb6dcf0e31fd097e01ccd6482734a14e28157..9d2d891bb2c5e60a28f8210d8b6e00bbcb616cd9 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/pointer_to_unary_function.cxx1z.fail.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/pointer_to_unary_function.cxx1z.fail.cpp
@@ -18,7 +18,9 @@
 
 double unary_f(int i) {return 0.5 - i;}
 
-int main()
+int main(int, char**)
 {
     typedef std::pointer_to_unary_function<int, double> F;
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/pointer_to_unary_function.pass.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/pointer_to_unary_function.pass.cpp
index e039fb4c60abc01004b4776f065a068769ebb63d..776fd309b564d4685df8f66916104fcec2009f4d 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/pointer_to_unary_function.pass.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/pointer_to_unary_function.pass.cpp
@@ -17,10 +17,12 @@
 
 double unary_f(int i) {return 0.5 - i;}
 
-int main()
+int main(int, char**)
 {
     typedef std::pointer_to_unary_function<int, double> F;
     static_assert((std::is_base_of<std::unary_function<int, double>, F>::value), "");
     const F f(unary_f);
     assert(f(36) == -35.5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/ptr_fun1.cxx1z.fail.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/ptr_fun1.cxx1z.fail.cpp
index 3efe3db5638016f0fa0a8dc66b506a716b992ed7..e0e7889e91f2869874a20c117fe1283b64247820 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/ptr_fun1.cxx1z.fail.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/ptr_fun1.cxx1z.fail.cpp
@@ -21,7 +21,9 @@
 
 double unary_f(int i) {return 0.5 - i;}
 
-int main()
+int main(int, char**)
 {
     assert(std::ptr_fun(unary_f)(36) == -35.5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/ptr_fun1.pass.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/ptr_fun1.pass.cpp
index 323a559815cbadf151a278d492d1d3c8c76c28e4..b356be2e90c8ed7b9f51d4e5270bbe86e96d6d4b 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/ptr_fun1.pass.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/ptr_fun1.pass.cpp
@@ -19,7 +19,9 @@
 
 double unary_f(int i) {return 0.5 - i;}
 
-int main()
+int main(int, char**)
 {
     assert(std::ptr_fun(unary_f)(36) == -35.5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/ptr_fun2.cxx1z.fail.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/ptr_fun2.cxx1z.fail.cpp
index d1ad2636264b4ad7a604df480218b002ba901d54..d975072966e57387dfcaccddbf219d6fed21a586 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/ptr_fun2.cxx1z.fail.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/ptr_fun2.cxx1z.fail.cpp
@@ -21,7 +21,9 @@
 
 double binary_f(int i, short j) {return i - j + .75;}
 
-int main()
+int main(int, char**)
 {
     assert(std::ptr_fun(binary_f)(36, 27) == 9.75);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/ptr_fun2.pass.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/ptr_fun2.pass.cpp
index 1bffccff58f6eb89f74fe287f1d6a0ac7a9bb67f..885f7db67a42f5258afef231af0b6989ed0ab076 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/ptr_fun2.pass.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.function.pointer.adaptors/ptr_fun2.pass.cpp
@@ -19,7 +19,9 @@
 
 double binary_f(int i, short j) {return i - j + .75;}
 
-int main()
+int main(int, char**)
 {
     assert(std::ptr_fun(binary_f)(36, 27) == 9.75);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun.cxx1z.fail.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun.cxx1z.fail.cpp
index 86cc02ec3dd65e215fc04667941f0536f447393e..e346f07ccb8d755926e5f8d3721f0823bd6a3344 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun.cxx1z.fail.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun.cxx1z.fail.cpp
@@ -27,8 +27,10 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     const A a = A();
     assert(std::mem_fun(&A::a3)(&a) == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun.pass.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun.pass.cpp
index f4a73e7536295bc4165e22a69c59a35b8320bf35..d7052ee5a33372ffed80ece160a14167a7cb4de4 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun.pass.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun.pass.cpp
@@ -24,8 +24,10 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     const A a = A();
     assert(std::mem_fun(&A::a3)(&a) == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun1.cxx1z.fail.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun1.cxx1z.fail.cpp
index 4f1e0aa70c685c86f7e3a4f204b6ae162c7a345d..e489a558ebd222d65f85fe42cbb110d64f62a5d4 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun1.cxx1z.fail.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun1.cxx1z.fail.cpp
@@ -27,8 +27,10 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     const A a = A();
     assert(std::mem_fun(&A::a4)(&a, 6) == 5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun1.pass.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun1.pass.cpp
index 6f89ec1802b36e1daad72e8c08c9e264f8357eef..f3c35f257f57e6b24df31039d33a2497afd0bad3 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun1.pass.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun1.pass.cpp
@@ -24,8 +24,10 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     const A a = A();
     assert(std::mem_fun(&A::a4)(&a, 6) == 5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun1_ref_t.cxx1z.fail.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun1_ref_t.cxx1z.fail.cpp
index 903e13c9755b68cce8851f8e5001d2fda2400a4c..14368e6e9e63262cc1d50b4d096c7647693cd43c 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun1_ref_t.cxx1z.fail.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun1_ref_t.cxx1z.fail.cpp
@@ -26,7 +26,9 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::const_mem_fun1_ref_t<double, A, unsigned> F;
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun1_ref_t.pass.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun1_ref_t.pass.cpp
index 6e6c60d60fb7fdc38b959598ea14302c0117fe96..50782e09aa4a8c4bd019fbb3c09a4efb958c7106 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun1_ref_t.pass.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun1_ref_t.pass.cpp
@@ -23,11 +23,13 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::const_mem_fun1_ref_t<double, A, unsigned> F;
     static_assert((std::is_base_of<std::binary_function<A, unsigned, double>, F>::value), "");
     const F f(&A::a4);
     const A a = A();
     assert(f(a, 6) == 5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun1_t.cxx1z.fail.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun1_t.cxx1z.fail.cpp
index 242c977a2beb295d0664441ca666464bbbb40e16..afa0b781ffc43a9f0a83586a56a74667ef0a9df6 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun1_t.cxx1z.fail.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun1_t.cxx1z.fail.cpp
@@ -26,7 +26,9 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::const_mem_fun1_t<double, A, unsigned> F;
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun1_t.pass.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun1_t.pass.cpp
index f4a78729e65bf8c66730a669ea707668759f5949..cf0218e8f9fa11dfef692e68ed2672b3046f3749 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun1_t.pass.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun1_t.pass.cpp
@@ -23,11 +23,13 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::const_mem_fun1_t<double, A, unsigned> F;
     static_assert((std::is_base_of<std::binary_function<const A*, unsigned, double>, F>::value), "");
     const F f(&A::a4);
     const A a = A();
     assert(f(&a, 6) == 5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_ref.cxx1z.fail.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_ref.cxx1z.fail.cpp
index 93322099da057eb70532797ee826368535dbae4b..1217cfe597bd4d6774a4557348a610fe398366b7 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_ref.cxx1z.fail.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_ref.cxx1z.fail.cpp
@@ -27,8 +27,10 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     const A a = A();
     assert(std::mem_fun_ref(&A::a3)(a) == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_ref.pass.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_ref.pass.cpp
index 5f05821c864540a2db4c45bfa952a56a76f81bb3..7765319908cee0e04ed358e1c6e20bd0514fa56f 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_ref.pass.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_ref.pass.cpp
@@ -24,8 +24,10 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     const A a = A();
     assert(std::mem_fun_ref(&A::a3)(a) == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_ref1.cxx1z.fail.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_ref1.cxx1z.fail.cpp
index 44eee11be20b8d4ddebddd110f9c6a68251505ee..58251d130922229c164741c8d63e27c0d19a1ff7 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_ref1.cxx1z.fail.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_ref1.cxx1z.fail.cpp
@@ -27,8 +27,10 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     const A a = A();
     assert(std::mem_fun_ref(&A::a4)(a, 6) == 5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_ref1.pass.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_ref1.pass.cpp
index 55586a91fc369a2999f8063c93ed14931c368a8a..4015675f8f4849915652d09858085cd74da8b4d1 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_ref1.pass.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_ref1.pass.cpp
@@ -24,8 +24,10 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     const A a = A();
     assert(std::mem_fun_ref(&A::a4)(a, 6) == 5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_ref_t.cxx1z.fail.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_ref_t.cxx1z.fail.cpp
index eac5820624b26cfe0dc8d8d4ec0c5d7cf15aa585..577cfe5376084d033d09c535ce7eb91330c3bb55 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_ref_t.cxx1z.fail.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_ref_t.cxx1z.fail.cpp
@@ -26,7 +26,9 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::const_mem_fun_ref_t<int, A> F;
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_ref_t.pass.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_ref_t.pass.cpp
index 3654ec2f196b8b9a144fd0d89efbd5b0d5f1382c..61382dc40f85fb2c285b3524dad1a7baa551c5f0 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_ref_t.pass.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_ref_t.pass.cpp
@@ -23,11 +23,13 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::const_mem_fun_ref_t<int, A> F;
     static_assert((std::is_base_of<std::unary_function<A, int>, F>::value), "");
     const F f(&A::a3);
     const A a = A();
     assert(f(a) == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_t.cxx1z.fail.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_t.cxx1z.fail.cpp
index 824cdf9adb748dcc19e01066c50254c906e61945..ee24e4116a1e39dead81733fc542b60806b49017 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_t.cxx1z.fail.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_t.cxx1z.fail.cpp
@@ -26,7 +26,9 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::const_mem_fun_t<int, A> F;
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_t.pass.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_t.pass.cpp
index 2814dccf8444a04127405cf26d35c80ffe4dce81..ca1065abfe89031cf0fa9313e9bb1519144153e7 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_t.pass.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/const_mem_fun_t.pass.cpp
@@ -23,11 +23,13 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::const_mem_fun_t<int, A> F;
     static_assert((std::is_base_of<std::unary_function<const A*, int>, F>::value), "");
     const F f(&A::a3);
     const A a = A();
     assert(f(&a) == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun.cxx1z.fail.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun.cxx1z.fail.cpp
index d54896c55a32cde36864d9500e8dc9502f4adfb0..a000ac5ee2fd617e7151439d6f72eee91b17298e 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun.cxx1z.fail.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun.cxx1z.fail.cpp
@@ -27,8 +27,10 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     A a;
     assert(std::mem_fun(&A::a1)(&a) == 5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun.pass.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun.pass.cpp
index e1bbb65d68bd519b95bd35665d57a5f51788a78f..6b707c4ad19ca802585313fb63d1e46feecde866 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun.pass.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun.pass.cpp
@@ -24,8 +24,10 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     A a;
     assert(std::mem_fun(&A::a1)(&a) == 5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun1.cxx1z.fail.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun1.cxx1z.fail.cpp
index c4f9dcb4ebc3da9b32ade73891d20e8e3d25b09d..626c9102e5c56aa65ad33667ac06e9ffa1859abf 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun1.cxx1z.fail.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun1.cxx1z.fail.cpp
@@ -27,8 +27,10 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     A a;
     assert(std::mem_fun(&A::a2)(&a, 5) == 6);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun1.pass.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun1.pass.cpp
index d5261e211a4a453f2e4ce6ddcdc306a996801016..5abf157a6ce9f5707fff8b0c44d7b9a257ac4627 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun1.pass.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun1.pass.cpp
@@ -24,8 +24,10 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     A a;
     assert(std::mem_fun(&A::a2)(&a, 5) == 6);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun1_ref_t.cxx1z.fail.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun1_ref_t.cxx1z.fail.cpp
index 653ea21479bd5e0aeb79a6951016d63cbb4c140a..4ac39e764211ea99bb0aa44ecc5a3cd67c66947e 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun1_ref_t.cxx1z.fail.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun1_ref_t.cxx1z.fail.cpp
@@ -26,7 +26,9 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::mem_fun1_ref_t<short, A, int> F;
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun1_ref_t.pass.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun1_ref_t.pass.cpp
index 416c20856c30738591013816dc5936ead40d52d9..ec21c42c9b6b19bd1f1295aa9e5f1ba5639b3fa1 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun1_ref_t.pass.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun1_ref_t.pass.cpp
@@ -23,11 +23,13 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::mem_fun1_ref_t<short, A, int> F;
     static_assert((std::is_base_of<std::binary_function<A, int, short>, F>::value), "");
     const F f(&A::a2);
     A a;
     assert(f(a, 5) == 6);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun1_t.cxx1z.fail.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun1_t.cxx1z.fail.cpp
index 3d77237a203fff74257a620c3414b17e05881167..6471f8e915317549bd412618ed9b616399314442 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun1_t.cxx1z.fail.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun1_t.cxx1z.fail.cpp
@@ -26,7 +26,9 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::mem_fun1_t<short, A, int> F;
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun1_t.pass.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun1_t.pass.cpp
index 8403d471d68ce8d3ca8b8c837842a0de95ce6676..d696bae067e7d736a2bf0ba9ea56a0d9ba82358c 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun1_t.pass.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun1_t.pass.cpp
@@ -23,11 +23,13 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::mem_fun1_t<short, A, int> F;
     static_assert((std::is_base_of<std::binary_function<A*, int, short>, F>::value), "");
     const F f(&A::a2);
     A a;
     assert(f(&a, 5) == 6);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_ref.cxx1z.fail.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_ref.cxx1z.fail.cpp
index 4eaa53eeee9a2b4aacf95dba6689a8b29f92f782..e6227509fb05e361a7678ff1578d6679963c201b 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_ref.cxx1z.fail.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_ref.cxx1z.fail.cpp
@@ -27,8 +27,10 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     A a;
     assert(std::mem_fun_ref(&A::a1)(a) == 5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_ref.pass.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_ref.pass.cpp
index 6ceff9257c04bcec2d44872b18ac1fc1aade1f15..e22a7f03d03a69e3384dfbbfb000fa8013190d27 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_ref.pass.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_ref.pass.cpp
@@ -24,8 +24,10 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     A a;
     assert(std::mem_fun_ref(&A::a1)(a) == 5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_ref1.cxx1z.fail.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_ref1.cxx1z.fail.cpp
index 2a73da49eabf85083871ed7aa6f77aae5b2ff5a1..c633e769dd65cc34def06d9d5a2400629793f3ae 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_ref1.cxx1z.fail.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_ref1.cxx1z.fail.cpp
@@ -27,8 +27,10 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     A a;
     assert(std::mem_fun_ref(&A::a2)(a, 5) == 6);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_ref1.pass.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_ref1.pass.cpp
index 19c4dca9e7a42bc64eac072cce59e75874a8f66e..1ff7a9af929e6aeeea5b4aaae627fe40c57054ec 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_ref1.pass.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_ref1.pass.cpp
@@ -24,8 +24,10 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     A a;
     assert(std::mem_fun_ref(&A::a2)(a, 5) == 6);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_ref_t.cxx1z.fail.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_ref_t.cxx1z.fail.cpp
index 0717a41b9801165b82219c481e125f7c930acbe3..02c3213be1549beefff2a59f88fef2481d2f1843 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_ref_t.cxx1z.fail.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_ref_t.cxx1z.fail.cpp
@@ -26,7 +26,9 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::mem_fun_ref_t<char, A> F;
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_ref_t.pass.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_ref_t.pass.cpp
index 0fac15b3d5c138591c540d8d60b8cff68482cae1..037454ed219803c6e57717b8beab1e6792616602 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_ref_t.pass.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_ref_t.pass.cpp
@@ -23,11 +23,13 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::mem_fun_ref_t<char, A> F;
     static_assert((std::is_base_of<std::unary_function<A, char>, F>::value), "");
     const F f(&A::a1);
     A a;
     assert(f(a) == 5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_t.cxx1z.fail.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_t.cxx1z.fail.cpp
index 25c3ce85f33ca4ea241fc56f70ab505d38b53d5b..ec379d7241b30b89f017f900d95d0713bfd1e27d 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_t.cxx1z.fail.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_t.cxx1z.fail.cpp
@@ -26,7 +26,9 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::mem_fun_t<char, A> F;
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_t.pass.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_t.pass.cpp
index 36205d11b23dc23bab644f7444e0dee768b29abe..e14ea14d12af56e665278fc8b88808240704cca8 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_t.pass.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/depr.member.pointer.adaptors/mem_fun_t.pass.cpp
@@ -23,11 +23,13 @@ struct A
     double a4(unsigned i) const {return i-1;}
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::mem_fun_t<char, A> F;
     static_assert((std::is_base_of<std::unary_function<A*, char>, F>::value), "");
     const F f(&A::a1);
     A a;
     assert(f(&a) == 5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/nothing_to_do.pass.cpp b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.adaptors/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.adaptors/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.base/binary_function.pass.cpp b/libcxx/test/std/depr/depr.function.objects/depr.base/binary_function.pass.cpp
index affa796364af63add67c9618eaa5565bea206b78..dbe6d1eb9ef903a26ee9f46bc997a4cc5ec35818 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.base/binary_function.pass.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.base/binary_function.pass.cpp
@@ -21,9 +21,11 @@
 #include <functional>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::binary_function<int, unsigned, char>::first_argument_type, int>::value), "");
     static_assert((std::is_same<std::binary_function<int, unsigned, char>::second_argument_type, unsigned>::value), "");
     static_assert((std::is_same<std::binary_function<int, unsigned, char>::result_type, char>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/depr.base/unary_function.pass.cpp b/libcxx/test/std/depr/depr.function.objects/depr.base/unary_function.pass.cpp
index c0be3d8a5e89b4a0396fbacdea78a2b4112e3582..0aaf3fc136c37decb8966bd3a198fda8e90b4101 100644
--- a/libcxx/test/std/depr/depr.function.objects/depr.base/unary_function.pass.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/depr.base/unary_function.pass.cpp
@@ -20,8 +20,10 @@
 #include <functional>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::unary_function<unsigned, char>::argument_type, unsigned>::value), "");
     static_assert((std::is_same<std::unary_function<unsigned, char>::result_type, char>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.function.objects/nothing_to_do.pass.cpp b/libcxx/test/std/depr/depr.function.objects/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/depr/depr.function.objects/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/depr/depr.function.objects/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.ios.members/io_state.pass.cpp b/libcxx/test/std/depr/depr.ios.members/io_state.pass.cpp
index 0806205990719778cccc48df00336f7dfe5677c9..37b23fc5e8c34417e2d2a91626a6a0011cb40e0b 100644
--- a/libcxx/test/std/depr/depr.ios.members/io_state.pass.cpp
+++ b/libcxx/test/std/depr/depr.ios.members/io_state.pass.cpp
@@ -20,10 +20,12 @@
 #include <strstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
 #if TEST_STD_VER <= 14
     std::strstream::io_state b = std::strstream::eofbit;
     assert(b == std::ios::eofbit);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.ios.members/open_mode.pass.cpp b/libcxx/test/std/depr/depr.ios.members/open_mode.pass.cpp
index b8088f651aa89d880afa6550927fd8864cfd20d0..57a88c957673a504d30f09c41ed039a5b8c5f36b 100644
--- a/libcxx/test/std/depr/depr.ios.members/open_mode.pass.cpp
+++ b/libcxx/test/std/depr/depr.ios.members/open_mode.pass.cpp
@@ -20,10 +20,12 @@
 #include <strstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
 #if TEST_STD_VER <= 14
     std::strstream::open_mode b = std::strstream::app;
     assert(b == std::ios::app);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.ios.members/seek_dir.pass.cpp b/libcxx/test/std/depr/depr.ios.members/seek_dir.pass.cpp
index 6c808cb71152fb45f67e1e213332762e0d23273b..5b48073bd2f110b749f08579a2dd1240728545f4 100644
--- a/libcxx/test/std/depr/depr.ios.members/seek_dir.pass.cpp
+++ b/libcxx/test/std/depr/depr.ios.members/seek_dir.pass.cpp
@@ -20,10 +20,12 @@
 #include <strstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
 #if TEST_STD_VER <= 14
     std::strstream::seek_dir b = std::strstream::cur;
     assert(b == std::ios::cur);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.ios.members/streamoff.pass.cpp b/libcxx/test/std/depr/depr.ios.members/streamoff.pass.cpp
index 66200175c0b6da416ed13b3dde40f62c7ef048bd..8abced55ee4ca39db0d89abef75193bfc28a22f1 100644
--- a/libcxx/test/std/depr/depr.ios.members/streamoff.pass.cpp
+++ b/libcxx/test/std/depr/depr.ios.members/streamoff.pass.cpp
@@ -20,10 +20,12 @@
 #include <ios>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
 #if TEST_STD_VER <= 14
     static_assert((std::is_integral<std::ios_base::streamoff>::value), "");
     static_assert((std::is_signed<std::ios_base::streamoff>::value), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.ios.members/streampos.pass.cpp b/libcxx/test/std/depr/depr.ios.members/streampos.pass.cpp
index 7af7c97e25ee65ac230e9719eba4ea7090ae75c4..7e95727033a362e79214e9b5872b4f351da9bebc 100644
--- a/libcxx/test/std/depr/depr.ios.members/streampos.pass.cpp
+++ b/libcxx/test/std/depr/depr.ios.members/streampos.pass.cpp
@@ -20,9 +20,11 @@
 #include <ios>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
 #if TEST_STD_VER <= 14
     static_assert((std::is_same<std::ios_base::streampos, std::streampos>::value), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.lib.binders/depr.lib.bind.1st/bind1st.depr_in_cxx11.fail.cpp b/libcxx/test/std/depr/depr.lib.binders/depr.lib.bind.1st/bind1st.depr_in_cxx11.fail.cpp
index b06816a225e539f2b84706e8d7965c2cfd79a9a1..e00cfe7c328565afa7b34bd3fcdfca2cc18a8a95 100644
--- a/libcxx/test/std/depr/depr.lib.binders/depr.lib.bind.1st/bind1st.depr_in_cxx11.fail.cpp
+++ b/libcxx/test/std/depr/depr.lib.binders/depr.lib.bind.1st/bind1st.depr_in_cxx11.fail.cpp
@@ -24,7 +24,9 @@
 #include "../test_func.h"
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     std::bind1st(test_func(1), 5); // expected-error{{'bind1st<test_func, int>' is deprecated}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.lib.binders/depr.lib.bind.1st/bind1st.pass.cpp b/libcxx/test/std/depr/depr.lib.binders/depr.lib.bind.1st/bind1st.pass.cpp
index e9fc7b39c01f77eb6dbe93cdbfdcb884e9695e95..5d89f369f98df44185dc0d3cbac1846176d9d013 100644
--- a/libcxx/test/std/depr/depr.lib.binders/depr.lib.bind.1st/bind1st.pass.cpp
+++ b/libcxx/test/std/depr/depr.lib.binders/depr.lib.bind.1st/bind1st.pass.cpp
@@ -18,7 +18,9 @@
 
 #include "../test_func.h"
 
-int main()
+int main(int, char**)
 {
     assert(std::bind1st(test_func(1), 5)(10.) == -5.);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.lib.binders/depr.lib.bind.2nd/bind2nd.depr_in_cxx11.fail.cpp b/libcxx/test/std/depr/depr.lib.binders/depr.lib.bind.2nd/bind2nd.depr_in_cxx11.fail.cpp
index eca83a007b688c204586fbf3c30a4d4b3b224439..d31189b0b980dee1eaf1fe9846264e467f963a29 100644
--- a/libcxx/test/std/depr/depr.lib.binders/depr.lib.bind.2nd/bind2nd.depr_in_cxx11.fail.cpp
+++ b/libcxx/test/std/depr/depr.lib.binders/depr.lib.bind.2nd/bind2nd.depr_in_cxx11.fail.cpp
@@ -24,7 +24,9 @@
 #include "../test_func.h"
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     std::bind2nd(test_func(1), 5); // expected-error{{'bind2nd<test_func, int>' is deprecated}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.lib.binders/depr.lib.bind.2nd/bind2nd.pass.cpp b/libcxx/test/std/depr/depr.lib.binders/depr.lib.bind.2nd/bind2nd.pass.cpp
index a7f19fe981345ce4260dbea4e19b071eb5b8c5e0..243ffd1165dd88a91daac076ce633ff1784dd31e 100644
--- a/libcxx/test/std/depr/depr.lib.binders/depr.lib.bind.2nd/bind2nd.pass.cpp
+++ b/libcxx/test/std/depr/depr.lib.binders/depr.lib.bind.2nd/bind2nd.pass.cpp
@@ -18,7 +18,9 @@
 
 #include "../test_func.h"
 
-int main()
+int main(int, char**)
 {
     assert(std::bind2nd(test_func(1), 5)(10) == 5.);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.lib.binders/depr.lib.binder.1st/binder1st.depr_in_cxx11.fail.cpp b/libcxx/test/std/depr/depr.lib.binders/depr.lib.binder.1st/binder1st.depr_in_cxx11.fail.cpp
index 3ee4154b925cc3c9d3106c650496eef2eeca0f6a..92d93b01f9eede938d04f4b7d5417dd48ec09cf0 100644
--- a/libcxx/test/std/depr/depr.lib.binders/depr.lib.binder.1st/binder1st.depr_in_cxx11.fail.cpp
+++ b/libcxx/test/std/depr/depr.lib.binders/depr.lib.binder.1st/binder1st.depr_in_cxx11.fail.cpp
@@ -24,7 +24,9 @@
 #include "../test_func.h"
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::binder1st<test_func> B1ST; // expected-error{{'binder1st<test_func>' is deprecated}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.lib.binders/depr.lib.binder.1st/binder1st.pass.cpp b/libcxx/test/std/depr/depr.lib.binders/depr.lib.binder.1st/binder1st.pass.cpp
index 18d4df48d58a0d4045436e4478b0096a57e8faf4..66df2614efde8d4abe695550be40c5d6e0119a66 100644
--- a/libcxx/test/std/depr/depr.lib.binders/depr.lib.binder.1st/binder1st.pass.cpp
+++ b/libcxx/test/std/depr/depr.lib.binders/depr.lib.binder.1st/binder1st.pass.cpp
@@ -51,8 +51,10 @@ public:
     }
 };
 
-int main()
+int main(int, char**)
 {
     test t;
     t.do_test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.lib.binders/depr.lib.binder.2nd/binder2nd.depr_in_cxx11.fail.cpp b/libcxx/test/std/depr/depr.lib.binders/depr.lib.binder.2nd/binder2nd.depr_in_cxx11.fail.cpp
index adecc53bd2a0aa63ff80f38206629604b5720df2..f2dd190726e31209647db9880f26b6f4256cfc42 100644
--- a/libcxx/test/std/depr/depr.lib.binders/depr.lib.binder.2nd/binder2nd.depr_in_cxx11.fail.cpp
+++ b/libcxx/test/std/depr/depr.lib.binders/depr.lib.binder.2nd/binder2nd.depr_in_cxx11.fail.cpp
@@ -24,7 +24,9 @@
 #include "../test_func.h"
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::binder2nd<test_func> B2ND; // expected-error{{'binder2nd<test_func>' is deprecated}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.lib.binders/depr.lib.binder.2nd/binder2nd.pass.cpp b/libcxx/test/std/depr/depr.lib.binders/depr.lib.binder.2nd/binder2nd.pass.cpp
index 3671d82448f5398917efd2980c92ef955d181061..f8cb7d46726c7214ade359118f1fd47f6009f720 100644
--- a/libcxx/test/std/depr/depr.lib.binders/depr.lib.binder.2nd/binder2nd.pass.cpp
+++ b/libcxx/test/std/depr/depr.lib.binders/depr.lib.binder.2nd/binder2nd.pass.cpp
@@ -51,8 +51,10 @@ public:
     }
 };
 
-int main()
+int main(int, char**)
 {
     test t;
     t.do_test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.lib.binders/nothing_to_do.pass.cpp b/libcxx/test/std/depr/depr.lib.binders/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/depr/depr.lib.binders/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/depr/depr.lib.binders/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.istrstream/depr.istrstream.cons/ccp.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.istrstream/depr.istrstream.cons/ccp.pass.cpp
index 9cce2a3d81bfc9f130d9ce183b93eab274ffab94..90288578f15104f6d066a96f6d03e54d53096637 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.istrstream/depr.istrstream.cons/ccp.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.istrstream/depr.istrstream.cons/ccp.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <string>
 
-int main()
+int main(int, char**)
 {
     {
         const char buf[] = "123 4.5 dog";
@@ -40,4 +40,6 @@ int main()
         assert(buf[9] == 'o');
         assert(buf[10] == 'g');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.istrstream/depr.istrstream.cons/ccp_size.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.istrstream/depr.istrstream.cons/ccp_size.pass.cpp
index 6cf4b621b38ae6474838a841c067a9c78b8cbb0e..867225bf851d50b5d3368fb48d87de5e1776a22f 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.istrstream/depr.istrstream.cons/ccp_size.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.istrstream/depr.istrstream.cons/ccp_size.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <string>
 
-int main()
+int main(int, char**)
 {
     {
         const char buf[] = "123 4.5 dog";
@@ -40,4 +40,6 @@ int main()
         assert(buf[5] == '.');
         assert(buf[6] == '5');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.istrstream/depr.istrstream.cons/cp.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.istrstream/depr.istrstream.cons/cp.pass.cpp
index b73bf32c9cd29bc6e77632174f7ffe5923fdbb88..106aaa7687a577f8d64e8c59c9d1786941cafa2a 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.istrstream/depr.istrstream.cons/cp.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.istrstream/depr.istrstream.cons/cp.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <string>
 
-int main()
+int main(int, char**)
 {
     {
         char buf[] = "123 4.5 dog";
@@ -40,4 +40,6 @@ int main()
         assert(buf[9] == 'g');
         assert(buf[10] == 'g');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.istrstream/depr.istrstream.cons/cp_size.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.istrstream/depr.istrstream.cons/cp_size.pass.cpp
index 914212031463b19fefa8fc127b49e8ae9aa8c325..79a0bfeec2fc7c77530a3342d47694a5ab58a7e0 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.istrstream/depr.istrstream.cons/cp_size.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.istrstream/depr.istrstream.cons/cp_size.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <string>
 
-int main()
+int main(int, char**)
 {
     {
         char buf[] = "123 4.5 dog";
@@ -40,4 +40,6 @@ int main()
         assert(buf[5] == '5');
         assert(buf[6] == '5');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.istrstream/depr.istrstream.members/rdbuf.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.istrstream/depr.istrstream.members/rdbuf.pass.cpp
index 66de73a570a807d2406650104c35a1ead88c3b2b..68b2ee8c40bb66b99bf82602c64b4b8cb666f9d9 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.istrstream/depr.istrstream.members/rdbuf.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.istrstream/depr.istrstream.members/rdbuf.pass.cpp
@@ -15,7 +15,7 @@
 #include <strstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         const char buf[] = "123 4.5 dog";
@@ -23,4 +23,6 @@ int main()
         std::strstreambuf* sb = in.rdbuf();
         assert(sb->sgetc() == '1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.istrstream/depr.istrstream.members/str.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.istrstream/depr.istrstream.members/str.pass.cpp
index f4b91c97a74d4017361596a9fbd00b0b5526558d..bae10783837bf873f636143848af260cec6c956e 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.istrstream/depr.istrstream.members/str.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.istrstream/depr.istrstream.members/str.pass.cpp
@@ -15,11 +15,13 @@
 #include <strstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         const char buf[] = "123 4.5 dog";
         std::istrstream in(buf);
         assert(in.str() == std::string("123 4.5 dog"));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.istrstream/types.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.istrstream/types.pass.cpp
index 94c2a48857823b5449987f25fbef0444cfb0fcdd..80f5af082d348f86ac01a5705ae6d58403840f54 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.istrstream/types.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.istrstream/types.pass.cpp
@@ -16,7 +16,9 @@
 #include <strstream>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::istream, std::istrstream>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.ostrstream/depr.ostrstream.cons/cp_size_mode.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.ostrstream/depr.ostrstream.cons/cp_size_mode.pass.cpp
index edece7db0a61a57fcc85c2ea8312f81787bed2c5..81c84fe321795c8a69ddeab78d800837c50b28d0 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.ostrstream/depr.ostrstream.cons/cp_size_mode.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.ostrstream/depr.ostrstream.cons/cp_size_mode.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <string>
 
-int main()
+int main(int, char**)
 {
     {
         char buf[] = "123 4.5 dog";
@@ -38,4 +38,6 @@ int main()
         out << i << ' ' << d << ' ' << s << std::ends;
         assert(out.str() == std::string("123 4.5 dog321 5.5 cat"));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.ostrstream/depr.ostrstream.cons/default.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.ostrstream/depr.ostrstream.cons/default.pass.cpp
index 96417da1163bc7d2fe09dc4e6c2c88616e7474f1..5f9e9e6a88ed7743432edcd0bc13f61ba60ef387 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.ostrstream/depr.ostrstream.cons/default.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.ostrstream/depr.ostrstream.cons/default.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <string>
 
-int main()
+int main(int, char**)
 {
     std::ostrstream out;
     int i = 123;
@@ -25,4 +25,6 @@ int main()
     out << i << ' ' << d << ' ' << s << std::ends;
     assert(out.str() == std::string("123 4.5 dog"));
     out.freeze(false);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.ostrstream/depr.ostrstream.members/freeze.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.ostrstream/depr.ostrstream.members/freeze.pass.cpp
index 817597168a869beb93afc9798d7c361e58889a73..4b3412edc880fe2aeae5f91a6429ee6f069bbe58 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.ostrstream/depr.ostrstream.members/freeze.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.ostrstream/depr.ostrstream.members/freeze.pass.cpp
@@ -15,7 +15,7 @@
 #include <strstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::ostrstream out;
@@ -30,4 +30,6 @@ int main()
         assert(out.str() == std::string("a"));
         out.freeze(false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.ostrstream/depr.ostrstream.members/pcount.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.ostrstream/depr.ostrstream.members/pcount.pass.cpp
index a592848ed0081ec5a1647ac144338b7bc8a63303..73a4bb81e25078616b6637f0e3a738f58544d4b4 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.ostrstream/depr.ostrstream.members/pcount.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.ostrstream/depr.ostrstream.members/pcount.pass.cpp
@@ -15,7 +15,7 @@
 #include <strstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::ostrstream out;
@@ -23,4 +23,6 @@ int main()
         out << 123 << ' ' << 4.5 << ' ' << "dog";
         assert(out.pcount() == 11);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.ostrstream/depr.ostrstream.members/rdbuf.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.ostrstream/depr.ostrstream.members/rdbuf.pass.cpp
index 547dde0644b44b678888ba56a76762063a09c012..ff58af45b204e49f2cf2cab17eb028772944e04a 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.ostrstream/depr.ostrstream.members/rdbuf.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.ostrstream/depr.ostrstream.members/rdbuf.pass.cpp
@@ -15,7 +15,7 @@
 #include <strstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         char buf[] = "123 4.5 dog";
@@ -24,4 +24,6 @@ int main()
         assert(sb->sputc('a') == 'a');
         assert(buf == std::string("a23 4.5 dog"));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.ostrstream/depr.ostrstream.members/str.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.ostrstream/depr.ostrstream.members/str.pass.cpp
index c9f3e8dc0059e2bdfe1677555e0cf71cccd5be8f..60ec02f341d24d7c29ce0c28489b645fc47c34e9 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.ostrstream/depr.ostrstream.members/str.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.ostrstream/depr.ostrstream.members/str.pass.cpp
@@ -15,7 +15,7 @@
 #include <strstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::ostrstream out;
@@ -23,4 +23,6 @@ int main()
         assert(out.str() == std::string("123 4.5 dog"));
         out.freeze(false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.ostrstream/types.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.ostrstream/types.pass.cpp
index b394f8326ad89f73a67c930e752d44d46f4dee9c..5fde850372300d561e5beca5524461348b1d2e7c 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.ostrstream/types.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.ostrstream/types.pass.cpp
@@ -16,7 +16,9 @@
 #include <strstream>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::ostream, std::ostrstream>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.strstream/depr.strstream.cons/cp_size_mode.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.strstream/depr.strstream.cons/cp_size_mode.pass.cpp
index 0a54296467092386ec4de75f3fda7f39e9274312..2387b1eebbe4a0e3b375357f6494fec328e65558 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.strstream/depr.strstream.cons/cp_size_mode.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.strstream/depr.strstream.cons/cp_size_mode.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <string>
 
-int main()
+int main(int, char**)
 {
     {
         char buf[] = "123 4.5 dog";
@@ -56,4 +56,6 @@ int main()
         inout << i << ' ' << d << ' ' << s;
         assert(inout.str() == std::string("123 4.5 dog321 5.5 cat"));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.strstream/depr.strstream.cons/default.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.strstream/depr.strstream.cons/default.pass.cpp
index ff68a3d1d8bededbe4625ac0c45c9357f5b2bfa5..0e278490ab7a79b637b7314071f975c64f6539e7 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.strstream/depr.strstream.cons/default.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.strstream/depr.strstream.cons/default.pass.cpp
@@ -17,7 +17,7 @@
 #include <cstring>
 #include <string>
 
-int main()
+int main(int, char**)
 {
     std::strstream inout;
     int i = 123;
@@ -33,4 +33,6 @@ int main()
     assert(d == 4.5);
     assert(std::strcmp(s.c_str(), "dog") == 0);
     inout.freeze(false);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.strstream/depr.strstream.dest/rdbuf.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.strstream/depr.strstream.dest/rdbuf.pass.cpp
index f02e713241624c3af541cf7886f442df85115c66..b4eb17397a6265b133f00a23fbbae422fc04b58f 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.strstream/depr.strstream.dest/rdbuf.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.strstream/depr.strstream.dest/rdbuf.pass.cpp
@@ -15,7 +15,7 @@
 #include <strstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         char buf[] = "123 4.5 dog";
@@ -24,4 +24,6 @@ int main()
         assert(sb->sputc('a') == 'a');
         assert(buf == std::string("a23 4.5 dog"));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.strstream/depr.strstream.oper/freeze.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.strstream/depr.strstream.oper/freeze.pass.cpp
index 8fd137ea67ee2252d26471d5652376517d9129f6..dab7c04a6bbae877475952a03ec6e0ca11a66bbb 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.strstream/depr.strstream.oper/freeze.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.strstream/depr.strstream.oper/freeze.pass.cpp
@@ -15,7 +15,7 @@
 #include <strstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::strstream out;
@@ -30,4 +30,6 @@ int main()
         assert(out.str() == std::string("a"));
         out.freeze(false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.strstream/depr.strstream.oper/pcount.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.strstream/depr.strstream.oper/pcount.pass.cpp
index 56624f2b26d41bfa8102fd95fcf90fd13a1a7b14..3a7641b23ea69f706c94fe252112e96f679877c8 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.strstream/depr.strstream.oper/pcount.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.strstream/depr.strstream.oper/pcount.pass.cpp
@@ -15,7 +15,7 @@
 #include <strstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::strstream out;
@@ -23,4 +23,6 @@ int main()
         out << 123 << ' ' << 4.5 << ' ' << "dog";
         assert(out.pcount() == 11);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.strstream/depr.strstream.oper/str.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.strstream/depr.strstream.oper/str.pass.cpp
index e780e843fbbaf03ff1d6110bf383f5dc6ad638e4..f3482c756d0d902351bc5a0f2b0b203c642ba5df 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.strstream/depr.strstream.oper/str.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.strstream/depr.strstream.oper/str.pass.cpp
@@ -15,7 +15,7 @@
 #include <strstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::strstream out;
@@ -23,4 +23,6 @@ int main()
         assert(out.str() == std::string("123 4.5 dog"));
         out.freeze(false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.strstream/types.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.strstream/types.pass.cpp
index 81979d0af50d0de56ff8238ed597ffefd870f346..7944b789996adab1c2d56ca6ab79e34027aceaf3 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.strstream/types.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.strstream/types.pass.cpp
@@ -21,11 +21,13 @@
 #include <strstream>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::iostream, std::strstream>::value), "");
     static_assert((std::is_same<std::strstream::char_type, char>::value), "");
     static_assert((std::is_same<std::strstream::int_type, std::char_traits<char>::int_type>::value), "");
     static_assert((std::is_same<std::strstream::pos_type, std::char_traits<char>::pos_type>::value), "");
     static_assert((std::is_same<std::strstream::off_type, std::char_traits<char>::off_type>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/ccp_size.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/ccp_size.pass.cpp
index e9003c9e63f3dbb05fa64b36446662b0885f91e5..08cb61914a6197e2dbaabef5052cffff0c4b98f6 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/ccp_size.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/ccp_size.pass.cpp
@@ -15,7 +15,7 @@
 #include <strstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         const char buf[] = "abcd";
@@ -36,4 +36,6 @@ int main()
         assert(sb.snextc() == 'd');
         assert(sb.snextc() == EOF);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/cp_size_cp.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/cp_size_cp.pass.cpp
index c5acd63a09783d6fe3c40380aa58960bf1fe9cd4..19eb15f948ce8a31ca538be8fcf7cb0f082cebcf 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/cp_size_cp.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/cp_size_cp.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstring>
 
-int main()
+int main(int, char**)
 {
     {
         char buf[] = "abcd";
@@ -93,4 +93,6 @@ int main()
         assert(sb.snextc() == 'j');
         assert(sb.snextc() == EOF);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/cscp_size.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/cscp_size.pass.cpp
index d38b8d3c8103ab104551fba726a215399287dc23..8cba11faca8137ff7b6dcf7ad36b50a0560f2c8a 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/cscp_size.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/cscp_size.pass.cpp
@@ -15,7 +15,7 @@
 #include <strstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         const signed char buf[] = "abcd";
@@ -36,4 +36,6 @@ int main()
         assert(sb.snextc() == 'd');
         assert(sb.snextc() == EOF);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/cucp_size.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/cucp_size.pass.cpp
index 03dc3056eca69cababca88122e58bf1baf3a4fbc..9546b74dbd563291b482217a6ed49da90e0c83a9 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/cucp_size.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/cucp_size.pass.cpp
@@ -15,7 +15,7 @@
 #include <strstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         unsigned char buf[] = "abcd";
@@ -36,4 +36,6 @@ int main()
         assert(sb.snextc() == 'd');
         assert(sb.snextc() == EOF);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/custom_alloc.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/custom_alloc.pass.cpp
index 997e6707c2f4fcc4f6c44d9620bc9002005f7dbf..d7587c0055e03cceb41125efc6145a6881c9c5b5 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/custom_alloc.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/custom_alloc.pass.cpp
@@ -38,7 +38,7 @@ struct test
         {return std::strstreambuf::overflow(c);}
 };
 
-int main()
+int main(int, char**)
 {
     {
         test s(my_alloc, my_free);
@@ -47,4 +47,6 @@ int main()
         assert(called == 1);
     }
     assert(called == 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/default.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/default.pass.cpp
index 49da5b2626d5f142fb20e1b82b2e364944b48dd9..2764efd0efda693ad2209c5c5cb3a31a785e8f30 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/default.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/default.pass.cpp
@@ -15,7 +15,7 @@
 #include <strstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::strstreambuf s;
@@ -27,4 +27,6 @@ int main()
         assert(s.str() == nullptr);
         assert(s.pcount() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/scp_size_scp.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/scp_size_scp.pass.cpp
index 5d419f7a4106f740a5bed5a6af2f5378baad0a8b..fdd46164bbbeac8b78c2685fe38aac6704a2acef 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/scp_size_scp.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/scp_size_scp.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstring>
 
-int main()
+int main(int, char**)
 {
     {
         signed char buf[] = "abcd";
@@ -93,4 +93,6 @@ int main()
         assert(sb.snextc() == 'j');
         assert(sb.snextc() == EOF);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/ucp_size_ucp.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/ucp_size_ucp.pass.cpp
index 6a7467dece33e962c330305dee721e6a3aa18df5..80aafd4481a46badabb7b52f03149733d0c7751e 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/ucp_size_ucp.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.cons/ucp_size_ucp.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstring>
 
-int main()
+int main(int, char**)
 {
     {
         unsigned char buf[] = "abcd";
@@ -93,4 +93,6 @@ int main()
         assert(sb.snextc() == 'j');
         assert(sb.snextc() == EOF);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.members/freeze.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.members/freeze.pass.cpp
index d798eb308b12dc5da4babde2d92b2f75b1b3e8e6..4cbb7b80aa7292f9d43f7b714cb1f7a278f4a201 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.members/freeze.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.members/freeze.pass.cpp
@@ -15,7 +15,7 @@
 #include <strstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::strstreambuf sb;
@@ -24,4 +24,6 @@ int main()
         sb.freeze(false);
         assert(sb.sputc('a') == 'a');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.members/overflow.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.members/overflow.pass.cpp
index 7d98f8cfd3dc6da0af7a5acfdba1c74888913c0e..b47a34ed8f7068f94cd571429fcc79d743f24d79 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.members/overflow.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.members/overflow.pass.cpp
@@ -20,7 +20,7 @@
 #include <string>
 #include <strstream>
 
-int main() {
+int main(int, char**) {
   std::ostrstream oss;
   std::string s;
 
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.members/pcount.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.members/pcount.pass.cpp
index 901dc4a9c5c856ec8a392d468bbd17e2531273b6..1d2f34d924b2f0a0c765b8a196aa6626860d914f 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.members/pcount.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.members/pcount.pass.cpp
@@ -15,7 +15,7 @@
 #include <strstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::strstreambuf sb;
@@ -28,4 +28,6 @@ int main()
         assert(sb.pcount() == 2);
         sb.freeze(false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.members/str.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.members/str.pass.cpp
index 933b6306e24b26f47aa511f827f065e3d9800e25..04ecb94cbd6459ab2143b091d67a6ceed921f128 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.members/str.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.members/str.pass.cpp
@@ -15,7 +15,7 @@
 #include <strstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::strstreambuf sb;
@@ -24,4 +24,6 @@ int main()
         assert(sb.str() == std::string("a"));
         sb.freeze(false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.virtuals/overflow.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.virtuals/overflow.pass.cpp
index 0e5f6a7e6e48b598ffc268470912c1587c7a6c52..19cb7abf12f9a47840598387d8a0167560e414b0 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.virtuals/overflow.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.virtuals/overflow.pass.cpp
@@ -15,7 +15,7 @@
 #include <strstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         char buf[12] = "abc";
@@ -43,4 +43,6 @@ int main()
         assert(sb.sputc('1') == '1');
         assert(sb.str() == std::string("12345678901"));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.virtuals/pbackfail.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.virtuals/pbackfail.pass.cpp
index 8364ab7ff94c6f6ae3fce883b4fa8f54409a3165..59fdb640d53a1ea65e01c620bd55ea705c271b26 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.virtuals/pbackfail.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.virtuals/pbackfail.pass.cpp
@@ -27,7 +27,7 @@ struct test
     virtual int_type pbackfail(int_type c = EOF) {return base::pbackfail(c);}
 };
 
-int main()
+int main(int, char**)
 {
     {
         const char buf[] = "123";
@@ -58,4 +58,6 @@ int main()
         assert(sb.pbackfail(EOF) == EOF);
         assert(sb.str() == std::string("133"));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.virtuals/seekoff.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.virtuals/seekoff.pass.cpp
index 9b5ba9ada70bd346d36689911ad09fcc50a9c8d4..8e1f22eeb117d1d333019b5c789f31e833cf30b7 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.virtuals/seekoff.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.virtuals/seekoff.pass.cpp
@@ -16,7 +16,7 @@
 #include <strstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         char buf[] = "0123456789";
@@ -53,4 +53,6 @@ int main()
         assert(sb.sputc('c') == 'c');
         assert(sb.str() == std::string("012a456c89"));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.virtuals/seekpos.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.virtuals/seekpos.pass.cpp
index f888a4d88cb5aed34e82b9ddcbdcc7a3fd746933..9d13dc4aa826bd85c979c62e518493bea12d927d 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.virtuals/seekpos.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.virtuals/seekpos.pass.cpp
@@ -16,7 +16,7 @@
 #include <strstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         char buf[] = "0123456789";
@@ -35,4 +35,6 @@ int main()
         assert(sb.sputc('a') == 'a');
         assert(sb.str() == std::string("012a456789"));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.virtuals/setbuf.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.virtuals/setbuf.pass.cpp
index 85c308ad57c577888ceb0b874d7af0eeb49f5335..c78004e21191899c2122480aa686f7e9b7037051 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.virtuals/setbuf.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.virtuals/setbuf.pass.cpp
@@ -15,7 +15,7 @@
 #include <strstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         char buf[] = "0123456789";
@@ -23,4 +23,6 @@ int main()
         assert(sb.pubsetbuf(0, 0) == &sb);
         assert(sb.str() == std::string("0123456789"));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.virtuals/underflow.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.virtuals/underflow.pass.cpp
index a28d943d9b963d6e1c1ae7fd82536de6c0591f56..e8da2957c6a96824ebb2df781e3e42641147b94d 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.virtuals/underflow.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/depr.strstreambuf.virtuals/underflow.pass.cpp
@@ -27,7 +27,7 @@ struct test
     base::int_type underflow() {return base::underflow();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         char buf[10] = "123";
@@ -47,4 +47,6 @@ int main()
         assert(sb.underflow() == '4');
         assert(sb.underflow() == '4');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/types.pass.cpp b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/types.pass.cpp
index 755916f653c5a2a75557abdf698165d87b6dede1..398605af98a5ac7002c8db506314f597707386dd 100644
--- a/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/types.pass.cpp
+++ b/libcxx/test/std/depr/depr.str.strstreams/depr.strstreambuf/types.pass.cpp
@@ -14,7 +14,9 @@
 #include <strstream>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::streambuf, std::strstreambuf>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/exception.unexpected/nothing_to_do.pass.cpp b/libcxx/test/std/depr/exception.unexpected/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/depr/exception.unexpected/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/depr/exception.unexpected/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/exception.unexpected/set.unexpected/get_unexpected.pass.cpp b/libcxx/test/std/depr/exception.unexpected/set.unexpected/get_unexpected.pass.cpp
index 0974b2ee95dee0a0d11d563dfd7458d4e2473834..7b11c3037f04b78c1a2f2f48eb21cbcf6e6ee1cf 100644
--- a/libcxx/test/std/depr/exception.unexpected/set.unexpected/get_unexpected.pass.cpp
+++ b/libcxx/test/std/depr/exception.unexpected/set.unexpected/get_unexpected.pass.cpp
@@ -22,7 +22,7 @@ void f3()
     std::exit(0);
 }
 
-int main()
+int main(int, char**)
 {
 
     std::unexpected_handler old = std::get_unexpected();
@@ -37,4 +37,6 @@ int main()
     std::set_terminate(f3);
     (*old)();
     assert(0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/exception.unexpected/set.unexpected/set_unexpected.pass.cpp b/libcxx/test/std/depr/exception.unexpected/set.unexpected/set_unexpected.pass.cpp
index f46d1d4eec0705232f6f5377116f7e877adccc84..38ae81ec9b07433cd15d4ce1bc3655b1211e8b8d 100644
--- a/libcxx/test/std/depr/exception.unexpected/set.unexpected/set_unexpected.pass.cpp
+++ b/libcxx/test/std/depr/exception.unexpected/set.unexpected/set_unexpected.pass.cpp
@@ -22,7 +22,7 @@ void f3()
     std::exit(0);
 }
 
-int main()
+int main(int, char**)
 {
     std::unexpected_handler old = std::set_unexpected(f1);
     // verify there is a previous unexpected handler
@@ -33,4 +33,6 @@ int main()
     std::set_terminate(f3);
     (*old)();
     assert(0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/exception.unexpected/unexpected.handler/unexpected_handler.pass.cpp b/libcxx/test/std/depr/exception.unexpected/unexpected.handler/unexpected_handler.pass.cpp
index 549f8e0a5ac8f04a153960e52e14f0e37ed4c55e..e4d4869d77a444c88c8e3f1ae71796e88a61c51f 100644
--- a/libcxx/test/std/depr/exception.unexpected/unexpected.handler/unexpected_handler.pass.cpp
+++ b/libcxx/test/std/depr/exception.unexpected/unexpected.handler/unexpected_handler.pass.cpp
@@ -14,8 +14,10 @@
 
 void f() {}
 
-int main()
+int main(int, char**)
 {
     std::unexpected_handler p = f;
     ((void)p);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/exception.unexpected/unexpected/unexpected.pass.cpp b/libcxx/test/std/depr/exception.unexpected/unexpected/unexpected.pass.cpp
index 883aa923757c68adafc6a4eb2042af66679b132e..2562b78848710bab1f3f951d4be130f6c806e4b8 100644
--- a/libcxx/test/std/depr/exception.unexpected/unexpected/unexpected.pass.cpp
+++ b/libcxx/test/std/depr/exception.unexpected/unexpected/unexpected.pass.cpp
@@ -19,9 +19,11 @@ void f1()
     std::exit(0);
 }
 
-int main()
+int main(int, char**)
 {
     std::set_unexpected(f1);
     std::unexpected();
     assert(false);
+
+  return 0;
 }
diff --git a/libcxx/test/std/depr/nothing_to_do.pass.cpp b/libcxx/test/std/depr/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/depr/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/depr/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/assertions/cassert.pass.cpp b/libcxx/test/std/diagnostics/assertions/cassert.pass.cpp
index fe54e1852df079d0bfb30cba135ab2e87c70b0fb..a18a4d0df039f5f758c42b6b030590557035c889 100644
--- a/libcxx/test/std/diagnostics/assertions/cassert.pass.cpp
+++ b/libcxx/test/std/diagnostics/assertions/cassert.pass.cpp
@@ -14,6 +14,8 @@
 #error assert not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/diagnostics.general/nothing_to_do.pass.cpp b/libcxx/test/std/diagnostics/diagnostics.general/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/diagnostics/diagnostics.general/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/diagnostics/diagnostics.general/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/errno/cerrno.pass.cpp b/libcxx/test/std/diagnostics/errno/cerrno.pass.cpp
index 100e5b30b0df302a95496318fbc84450d887b5fb..452f99e337afad2b5e50de3f777446d4e6dfc945 100644
--- a/libcxx/test/std/diagnostics/errno/cerrno.pass.cpp
+++ b/libcxx/test/std/diagnostics/errno/cerrno.pass.cpp
@@ -339,6 +339,8 @@
 #error errno not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/nothing_to_do.pass.cpp b/libcxx/test/std/diagnostics/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/diagnostics/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/diagnostics/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/std.exceptions/domain.error/domain_error.pass.cpp b/libcxx/test/std/diagnostics/std.exceptions/domain.error/domain_error.pass.cpp
index 14ded723f161a06cfcf4b17f9b226055a35475b0..31a320d113aefe5b8441d4c70fe00952d1eecf3b 100644
--- a/libcxx/test/std/diagnostics/std.exceptions/domain.error/domain_error.pass.cpp
+++ b/libcxx/test/std/diagnostics/std.exceptions/domain.error/domain_error.pass.cpp
@@ -14,7 +14,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::logic_error, std::domain_error>::value),
                  "std::is_base_of<std::logic_error, std::domain_error>::value");
@@ -38,4 +38,6 @@ int main()
     e2 = e;
     assert(e2.what() == msg);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/std.exceptions/invalid.argument/invalid_argument.pass.cpp b/libcxx/test/std/diagnostics/std.exceptions/invalid.argument/invalid_argument.pass.cpp
index bcdfe477b357327cb41b2e11b161de80425a16a8..00d9a9296dfa8431821c2833bb696570fedf6ef2 100644
--- a/libcxx/test/std/diagnostics/std.exceptions/invalid.argument/invalid_argument.pass.cpp
+++ b/libcxx/test/std/diagnostics/std.exceptions/invalid.argument/invalid_argument.pass.cpp
@@ -14,7 +14,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::logic_error, std::invalid_argument>::value),
                  "std::is_base_of<std::logic_error, std::invalid_argument>::value");
@@ -38,4 +38,6 @@ int main()
     e2 = e;
     assert(e2.what() == msg);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/std.exceptions/length.error/length_error.pass.cpp b/libcxx/test/std/diagnostics/std.exceptions/length.error/length_error.pass.cpp
index 754f7906152e01bc7392ae9dfec5fe84b569cad9..1e8f1e46c8e2b881e66c2c69c55edc7706dd3101 100644
--- a/libcxx/test/std/diagnostics/std.exceptions/length.error/length_error.pass.cpp
+++ b/libcxx/test/std/diagnostics/std.exceptions/length.error/length_error.pass.cpp
@@ -14,7 +14,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::logic_error, std::length_error>::value),
                  "std::is_base_of<std::logic_error, std::length_error>::value");
@@ -38,4 +38,6 @@ int main()
     e2 = e;
     assert(e2.what() == msg);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/std.exceptions/logic.error/logic_error.pass.cpp b/libcxx/test/std/diagnostics/std.exceptions/logic.error/logic_error.pass.cpp
index 279ac7345b741f261beece9607bb867337f07520..e30b3b9f8ee33515a1a7c4f95fdb9f3f6e2b737c 100644
--- a/libcxx/test/std/diagnostics/std.exceptions/logic.error/logic_error.pass.cpp
+++ b/libcxx/test/std/diagnostics/std.exceptions/logic.error/logic_error.pass.cpp
@@ -14,7 +14,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::exception, std::logic_error>::value),
                  "std::is_base_of<std::exception, std::logic_error>::value");
@@ -38,4 +38,6 @@ int main()
     e2 = e;
     assert(e2.what() == msg);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/std.exceptions/out.of.range/out_of_range.pass.cpp b/libcxx/test/std/diagnostics/std.exceptions/out.of.range/out_of_range.pass.cpp
index 8f5a8f2f806ed66c39f8599c354a4f77ad034e58..01a5b46b4a45f658b99c81e9011f0b214f2920a0 100644
--- a/libcxx/test/std/diagnostics/std.exceptions/out.of.range/out_of_range.pass.cpp
+++ b/libcxx/test/std/diagnostics/std.exceptions/out.of.range/out_of_range.pass.cpp
@@ -14,7 +14,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::logic_error, std::out_of_range>::value),
                  "std::is_base_of<std::logic_error, std::out_of_range>::value");
@@ -38,4 +38,6 @@ int main()
     e2 = e;
     assert(e2.what() == msg);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/std.exceptions/overflow.error/overflow_error.pass.cpp b/libcxx/test/std/diagnostics/std.exceptions/overflow.error/overflow_error.pass.cpp
index 0e576290d8ebf5f0ab050ed087817ce75db73ff9..a9e7fb994229841c806e3514f4538a0357943fbc 100644
--- a/libcxx/test/std/diagnostics/std.exceptions/overflow.error/overflow_error.pass.cpp
+++ b/libcxx/test/std/diagnostics/std.exceptions/overflow.error/overflow_error.pass.cpp
@@ -14,7 +14,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::runtime_error, std::overflow_error>::value),
                  "std::is_base_of<std::runtime_error, std::overflow_error>::value");
@@ -38,4 +38,6 @@ int main()
     e2 = e;
     assert(e2.what() == msg);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/std.exceptions/range.error/range_error.pass.cpp b/libcxx/test/std/diagnostics/std.exceptions/range.error/range_error.pass.cpp
index 211c53d12e2694b9824de2c93147142f2a83a547..92d1151ff6c1a6145f97c611d8623ce746e2a111 100644
--- a/libcxx/test/std/diagnostics/std.exceptions/range.error/range_error.pass.cpp
+++ b/libcxx/test/std/diagnostics/std.exceptions/range.error/range_error.pass.cpp
@@ -14,7 +14,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::runtime_error, std::range_error>::value),
                  "std::is_base_of<std::runtime_error, std::range_error>::value");
@@ -38,4 +38,6 @@ int main()
     e2 = e;
     assert(e2.what() == msg);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/std.exceptions/runtime.error/runtime_error.pass.cpp b/libcxx/test/std/diagnostics/std.exceptions/runtime.error/runtime_error.pass.cpp
index dae3371cd99b92688c2d46d6a5c381e3f2367c81..c4b8eea74c8f63fe2f24037ac90994d2ac9aaa50 100644
--- a/libcxx/test/std/diagnostics/std.exceptions/runtime.error/runtime_error.pass.cpp
+++ b/libcxx/test/std/diagnostics/std.exceptions/runtime.error/runtime_error.pass.cpp
@@ -14,7 +14,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::exception, std::runtime_error>::value),
                  "std::is_base_of<std::exception, std::runtime_error>::value");
@@ -38,4 +38,6 @@ int main()
     e2 = e;
     assert(e2.what() == msg);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/std.exceptions/underflow.error/underflow_error.pass.cpp b/libcxx/test/std/diagnostics/std.exceptions/underflow.error/underflow_error.pass.cpp
index f2588576a6ea89ecf722f9fce50c8faf85e381e1..88a3f46fbdc8cb482366b88db23d410f585a6031 100644
--- a/libcxx/test/std/diagnostics/std.exceptions/underflow.error/underflow_error.pass.cpp
+++ b/libcxx/test/std/diagnostics/std.exceptions/underflow.error/underflow_error.pass.cpp
@@ -14,7 +14,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::runtime_error, std::underflow_error>::value),
                  "std::is_base_of<std::runtime_error, std::underflow_error>::value");
@@ -38,4 +38,6 @@ int main()
     e2 = e;
     assert(e2.what() == msg);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/errc.pass.cpp b/libcxx/test/std/diagnostics/syserr/errc.pass.cpp
index 0738264afdb8362d3229ac24a6a4ce01a075374a..201878d2dd58c59147477b677cc2f23f77bb2151 100644
--- a/libcxx/test/std/diagnostics/syserr/errc.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/errc.pass.cpp
@@ -12,7 +12,7 @@
 
 #include <system_error>
 
-int main()
+int main(int, char**)
 {
     static_assert(static_cast<int>(std::errc::address_family_not_supported) == EAFNOSUPPORT, "");
     static_assert(static_cast<int>(std::errc::address_in_use) == EADDRINUSE, "");
@@ -100,4 +100,6 @@ int main()
     static_assert(static_cast<int>(std::errc::too_many_symbolic_link_levels) == ELOOP, "");
     static_assert(static_cast<int>(std::errc::value_too_large) == EOVERFLOW, "");
     static_assert(static_cast<int>(std::errc::wrong_protocol_type) == EPROTOTYPE, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/is_error_code_enum.pass.cpp b/libcxx/test/std/diagnostics/syserr/is_error_code_enum.pass.cpp
index 2b1416e15d6c7f14d089a3a73c6bb082a6d2f1cd..2a44b5ee352d30909d21bce53219eec4dcf10833 100644
--- a/libcxx/test/std/diagnostics/syserr/is_error_code_enum.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/is_error_code_enum.pass.cpp
@@ -39,7 +39,7 @@ namespace std
 }
 
 
-int main()
+int main(int, char**)
 {
     test<false, void>();
     test<false, int>();
@@ -47,4 +47,6 @@ int main()
     test<false, std::string>();
 
     test<true, A>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/is_error_condition_enum.pass.cpp b/libcxx/test/std/diagnostics/syserr/is_error_condition_enum.pass.cpp
index 8398c70febbfca5b41e09cc2de446462e055137b..df89fc334b246a1693e740110179714a3c542ef7 100644
--- a/libcxx/test/std/diagnostics/syserr/is_error_condition_enum.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/is_error_condition_enum.pass.cpp
@@ -39,7 +39,7 @@ namespace std
 }
 
 
-int main()
+int main(int, char**)
 {
     test<false, void>();
     test<false, int>();
@@ -47,4 +47,6 @@ int main()
     test<false, std::string>();
 
     test<true, A>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.compare/eq_error_code_error_code.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.compare/eq_error_code_error_code.pass.cpp
index 425406ade46336ee7085940c2473a510c6a40a43..0e2dbe552bd726eb35d6b234ccbf41c4691836e0 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.compare/eq_error_code_error_code.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.compare/eq_error_code_error_code.pass.cpp
@@ -20,7 +20,7 @@
 #include <system_error>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::error_code e_code1(5, std::generic_category());
     std::error_code e_code2(5, std::system_category());
@@ -102,4 +102,6 @@ int main()
     assert(e_condition4 != e_condition2);
     assert(e_condition4 != e_condition3);
     assert(e_condition4 == e_condition4);
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcat/nothing_to_do.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcat/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcat/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcat/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.derived/message.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.derived/message.pass.cpp
index 8aa7fedf6f8c55ad9442cc31bd6921de60c47b7b..ed580198efc4cba73fbf5e54e9c27b693f87ddd8 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.derived/message.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.derived/message.pass.cpp
@@ -18,7 +18,7 @@
 
 #include <stdio.h>
 
-int main()
+int main(int, char**)
 {
     const std::error_category& e_cat1 = std::generic_category();
     const std::error_category& e_cat2 = std::system_category();
@@ -30,4 +30,6 @@ int main()
     assert(!m3.empty());
     assert(m1 == m2);
     assert(m1 != m3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.nonvirtuals/default_ctor.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.nonvirtuals/default_ctor.pass.cpp
index 8e5bda76297e3b67cd916d9f0be7f8549cc4cf68..185f96e26eb9e1b86266127bcc6b625adf260a53 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.nonvirtuals/default_ctor.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.nonvirtuals/default_ctor.pass.cpp
@@ -27,8 +27,10 @@ public:
     virtual std::string message(int) const {return std::string();}
 };
 
-int main()
+int main(int, char**)
 {
     static_assert(std::is_nothrow_default_constructible<test1>::value,
                                  "error_category() must exist and be noexcept");
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.nonvirtuals/eq.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.nonvirtuals/eq.pass.cpp
index abe0c36873f7bb79974548745a1b56557d17c0d7..ce09481e324889f207e7553b04138fec0ea783e3 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.nonvirtuals/eq.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.nonvirtuals/eq.pass.cpp
@@ -15,11 +15,13 @@
 #include <system_error>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::error_category& e_cat1 = std::generic_category();
     const std::error_category& e_cat2 = std::generic_category();
     const std::error_category& e_cat3 = std::system_category();
     assert(e_cat1 == e_cat2);
     assert(!(e_cat1 == e_cat3));
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.nonvirtuals/lt.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.nonvirtuals/lt.pass.cpp
index 9b9a1acc0f25dd074b189797c41c884eca71a74f..db6b3b90814e1a5532d5a8c6e002429b9798639e 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.nonvirtuals/lt.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.nonvirtuals/lt.pass.cpp
@@ -15,11 +15,13 @@
 #include <system_error>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::error_category& e_cat1 = std::generic_category();
     const std::error_category& e_cat2 = std::generic_category();
     const std::error_category& e_cat3 = std::system_category();
     assert(!(e_cat1 < e_cat2) && !(e_cat2 < e_cat1));
     assert((e_cat1 < e_cat3) || (e_cat3 < e_cat1));
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.nonvirtuals/neq.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.nonvirtuals/neq.pass.cpp
index 615c9a0bec624a2dba38e07ec07e70098b20baa1..2826018d3d57cfba947ce79e58b25e0ae7ad5d58 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.nonvirtuals/neq.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.nonvirtuals/neq.pass.cpp
@@ -15,11 +15,13 @@
 #include <system_error>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::error_category& e_cat1 = std::generic_category();
     const std::error_category& e_cat2 = std::generic_category();
     const std::error_category& e_cat3 = std::system_category();
     assert(!(e_cat1 != e_cat2));
     assert(e_cat1 != e_cat3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.objects/generic_category.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.objects/generic_category.pass.cpp
index 73967e90f42590128ccb5c10f36a18b7011afc69..f04427381cbbb751ffc97950f4f9aa79b120e877 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.objects/generic_category.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.objects/generic_category.pass.cpp
@@ -35,7 +35,7 @@ void test_message_for_bad_value() {
     assert(errno == E2BIG);
 }
 
-int main()
+int main(int, char**)
 {
     const std::error_category& e_cat1 = std::generic_category();
     std::string m1 = e_cat1.name();
@@ -43,4 +43,6 @@ int main()
     {
         test_message_for_bad_value();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.objects/system_category.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.objects/system_category.pass.cpp
index 78d3a3ef00c4eaac6394265b422ea1a1dd58410b..8374c8766b2eaaa89287fb81a3dd9dd247baab42 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.objects/system_category.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.objects/system_category.pass.cpp
@@ -35,7 +35,7 @@ void test_message_for_bad_value() {
     assert(errno == E2BIG);
 }
 
-int main()
+int main(int, char**)
 {
     const std::error_category& e_cat1 = std::system_category();
     std::error_condition e_cond = e_cat1.default_error_condition(5);
@@ -47,4 +47,6 @@ int main()
     {
         test_message_for_bad_value();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.overview/error_category.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.overview/error_category.pass.cpp
index b75b6b92437b2b3c0ffb9af09d1365cd3717b6c2..112c3944885fdbafa3ae6304cc3885f32bd2f95b 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.overview/error_category.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.overview/error_category.pass.cpp
@@ -12,8 +12,10 @@
 
 #include <system_error>
 
-int main()
+int main(int, char**)
 {
     std::error_category* p = 0;
     ((void)p);
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.virtuals/default_error_condition.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.virtuals/default_error_condition.pass.cpp
index 870822cbcbe1925c7bab3dbbff626f22e4abc0ec..07daf6f4912790d738c1852363572428967ad45c 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.virtuals/default_error_condition.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.virtuals/default_error_condition.pass.cpp
@@ -15,10 +15,12 @@
 #include <system_error>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::error_category& e_cat = std::generic_category();
     std::error_condition e_cond = e_cat.default_error_condition(static_cast<int>(std::errc::not_a_directory));
     assert(e_cond.category() == e_cat);
     assert(e_cond.value() == static_cast<int>(std::errc::not_a_directory));
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.virtuals/equivalent_error_code_int.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.virtuals/equivalent_error_code_int.pass.cpp
index 89eb8b475233eae46c7640ec08b93bf6bf955748..7682227980ed5940ef449fedd8cfc0e72be4eb01 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.virtuals/equivalent_error_code_int.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.virtuals/equivalent_error_code_int.pass.cpp
@@ -15,9 +15,11 @@
 #include <system_error>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::error_category& e_cat = std::generic_category();
     assert(e_cat.equivalent(std::error_code(5, e_cat), 5));
     assert(!e_cat.equivalent(std::error_code(5, e_cat), 6));
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.virtuals/equivalent_int_error_condition.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.virtuals/equivalent_int_error_condition.pass.cpp
index 76cc198382b92832fb160d1c02eacf34941b120a..7e627d4097a88f86188a73b681016b33d6fb5d4a 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.virtuals/equivalent_int_error_condition.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcat/syserr.errcat.virtuals/equivalent_int_error_condition.pass.cpp
@@ -15,10 +15,12 @@
 #include <system_error>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::error_category& e_cat = std::generic_category();
     std::error_condition e_cond = e_cat.default_error_condition(5);
     assert(e_cat.equivalent(5, e_cond));
     assert(!e_cat.equivalent(6, e_cond));
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcode/nothing_to_do.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcode/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcode/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcode/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.constructors/ErrorCodeEnum.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.constructors/ErrorCodeEnum.pass.cpp
index 50f48e170bc7a9ad12fb8b83b9aaec44d2074f23..bfebd012b8d0df96c726dc6dfce288a1c511412a 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.constructors/ErrorCodeEnum.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.constructors/ErrorCodeEnum.pass.cpp
@@ -33,11 +33,13 @@ make_error_code(testing x)
     return std::error_code(static_cast<int>(x), std::generic_category());
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::error_code ec(two);
         assert(ec.value() == 2);
         assert(ec.category() == std::generic_category());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.constructors/default.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.constructors/default.pass.cpp
index 9d7fbba1dfb1e6285c45e5277fe25dc6c8a16560..3a7249edeae74cf64416913b67653a93bf65302d 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.constructors/default.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.constructors/default.pass.cpp
@@ -15,9 +15,11 @@
 #include <system_error>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::error_code ec;
     assert(ec.value() == 0);
     assert(ec.category() == std::system_category());
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.constructors/int_error_category.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.constructors/int_error_category.pass.cpp
index 99d8f94076841fe026e6ad6b4bce4aa5b928e5a7..5a2150fbf7ffb08b2d560b4969d38bb2a8b9865e 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.constructors/int_error_category.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.constructors/int_error_category.pass.cpp
@@ -15,7 +15,7 @@
 #include <system_error>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::error_code ec(6, std::system_category());
@@ -27,4 +27,6 @@ int main()
         assert(ec.value() == 8);
         assert(ec.category() == std::generic_category());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.modifiers/ErrorCodeEnum.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.modifiers/ErrorCodeEnum.pass.cpp
index aa99f4b3a891e1f25d24feeaf5c4b350ccbc2f3e..a98e22944568fa7290aac572539882ee1a1d37d6 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.modifiers/ErrorCodeEnum.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.modifiers/ErrorCodeEnum.pass.cpp
@@ -33,7 +33,7 @@ make_error_code(testing x)
     return std::error_code(static_cast<int>(x), std::generic_category());
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::error_code ec;
@@ -41,4 +41,6 @@ int main()
         assert(ec.value() == 2);
         assert(ec.category() == std::generic_category());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.modifiers/assign.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.modifiers/assign.pass.cpp
index 2c06d4b937978ac427a6b38c6fe844c73f41e2e1..998cfd3545e18e56eb5d5cd1a037986fe876950f 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.modifiers/assign.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.modifiers/assign.pass.cpp
@@ -15,7 +15,7 @@
 #include <system_error>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::error_code ec;
@@ -29,4 +29,6 @@ int main()
         assert(ec.value() == 8);
         assert(ec.category() == std::generic_category());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.modifiers/clear.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.modifiers/clear.pass.cpp
index 523562c8e257bab533c8701d52f120660c51ba1a..c4b7eca258a43470deeb0f4f45092ff8afb616fb 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.modifiers/clear.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.modifiers/clear.pass.cpp
@@ -15,7 +15,7 @@
 #include <system_error>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::error_code ec;
@@ -26,4 +26,6 @@ int main()
         assert(ec.value() == 0);
         assert(ec.category() == std::system_category());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.nonmembers/lt.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.nonmembers/lt.pass.cpp
index 98f46eea650d64696e95c2e24712de1810819e03..9dc37fc342528360c8d64fcee6a698f722a90591 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.nonmembers/lt.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.nonmembers/lt.pass.cpp
@@ -16,11 +16,13 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         const std::error_code ec1(6, std::generic_category());
         const std::error_code ec2(7, std::generic_category());
         assert(ec1 < ec2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.nonmembers/make_error_code.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.nonmembers/make_error_code.pass.cpp
index 7917de06e59bfa03c63d7e6acdd4f576cef79539..1f4603f7c9872e4d80d9954d04725573a22d8c05 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.nonmembers/make_error_code.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.nonmembers/make_error_code.pass.cpp
@@ -15,11 +15,13 @@
 #include <system_error>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::error_code ec = make_error_code(std::errc::operation_canceled);
         assert(ec.value() == static_cast<int>(std::errc::operation_canceled));
         assert(ec.category() == std::generic_category());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.nonmembers/stream_inserter.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.nonmembers/stream_inserter.pass.cpp
index 0828c1fb8e545145727dfbc72ef605f66e7699cb..37e1d817dbbf52907bcee230ccf31bdbaae57636 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.nonmembers/stream_inserter.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.nonmembers/stream_inserter.pass.cpp
@@ -18,9 +18,11 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::ostringstream out;
     out << std::error_code(std::io_errc::stream);
     assert(out.str() == "iostream:1");
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.observers/bool.fail.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.observers/bool.fail.cpp
index 6b9838ca73d0bb4f7fb36b08994f3808e6bd1dec..902e108a1c1b45c7c2c989e5cf3ef7daa78a56c2 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.observers/bool.fail.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.observers/bool.fail.cpp
@@ -22,7 +22,7 @@ bool test_func(void)
     return ec;   // conversion to bool is explicit; should fail.
 }
 
-int main()
+int main(int, char**)
 {
     return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.observers/bool.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.observers/bool.pass.cpp
index da226788c21cbf127efe6e8a3bf5bde12077c357..11bea5a344e644ed578348dbb3705d402422fdc5 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.observers/bool.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.observers/bool.pass.cpp
@@ -16,7 +16,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         const std::error_code ec(6, std::generic_category());
@@ -26,4 +26,6 @@ int main()
         const std::error_code ec(0, std::generic_category());
         assert(!static_cast<bool>(ec));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.observers/category.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.observers/category.pass.cpp
index a2a9ef717b273d69758ac6fa94ddb2f6495d4f45..16197d934a09f6b0b7386d4aa21498795d4c3911 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.observers/category.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.observers/category.pass.cpp
@@ -15,8 +15,10 @@
 #include <system_error>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::error_code ec(6, std::generic_category());
     assert(ec.category() == std::generic_category());
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.observers/default_error_condition.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.observers/default_error_condition.pass.cpp
index e7119a3e67114b87071389e74c7765be788ec053..4c92b488e2054e6baf5e9525af1fdf593d1db5c3 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.observers/default_error_condition.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.observers/default_error_condition.pass.cpp
@@ -15,7 +15,7 @@
 #include <system_error>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         const std::error_code ec(6, std::generic_category());
@@ -27,4 +27,6 @@ int main()
         std::error_condition e_cond = ec.default_error_condition();
         assert(e_cond == ec);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.observers/message.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.observers/message.pass.cpp
index 7482914e6728e140c0c864c557f499c5564f9df3..513eeae77d5be2915edf362c962bd6be56bc0ee2 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.observers/message.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.observers/message.pass.cpp
@@ -16,8 +16,10 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::error_code ec(6, std::generic_category());
     assert(ec.message() == std::generic_category().message(6));
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.observers/value.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.observers/value.pass.cpp
index 5e15e06300dbf9f4fca826d528091917a97ecd69..f1fcee4146991d734d9508b2695931106fa7874f 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.observers/value.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.observers/value.pass.cpp
@@ -15,8 +15,10 @@
 #include <system_error>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::error_code ec(6, std::system_category());
     assert(ec.value() == 6);
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.overview/types.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.overview/types.pass.cpp
index c5f8650d2f54d79bbc1a39fe460a9437d98678ba..b2441ac974652de4426af7e4618cd5a379bafe42 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.overview/types.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcode/syserr.errcode.overview/types.pass.cpp
@@ -14,10 +14,12 @@
 #include <system_error>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     std::error_code x;
     TEST_IGNORE_NODISCARD  x.category();   // returns a std::error_category &
     TEST_IGNORE_NODISCARD  x.default_error_condition(); // std::error_condition
     TEST_IGNORE_NODISCARD  x.message();    // returns a std::string
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcondition/nothing_to_do.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcondition/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcondition/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcondition/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.constructors/ErrorConditionEnum.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.constructors/ErrorConditionEnum.pass.cpp
index 34c3af883d5f2e477d2678e33d593a87fa9d6192..63e718dda308b6c2e593e245dbee5b0904a84c2e 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.constructors/ErrorConditionEnum.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.constructors/ErrorConditionEnum.pass.cpp
@@ -15,11 +15,13 @@
 #include <system_error>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::error_condition ec(std::errc::not_a_directory);
         assert(ec.value() == static_cast<int>(std::errc::not_a_directory));
         assert(ec.category() == std::generic_category());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.constructors/default.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.constructors/default.pass.cpp
index e303920102e122b86f2088daa33b0d7c9dbe0e59..f39904a12e8f8872ac3f12815da63b55d6b1ddc2 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.constructors/default.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.constructors/default.pass.cpp
@@ -15,9 +15,11 @@
 #include <system_error>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::error_condition ec;
     assert(ec.value() == 0);
     assert(ec.category() == std::generic_category());
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.constructors/int_error_category.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.constructors/int_error_category.pass.cpp
index 82b0de8b6cf55976b068a143d9f3c71cdd256c52..b30c23f1913fcb7ede689529733de46821a2fb31 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.constructors/int_error_category.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.constructors/int_error_category.pass.cpp
@@ -15,7 +15,7 @@
 #include <system_error>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::error_condition ec(6, std::system_category());
@@ -27,4 +27,6 @@ int main()
         assert(ec.value() == 8);
         assert(ec.category() == std::generic_category());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.modifiers/ErrorConditionEnum.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.modifiers/ErrorConditionEnum.pass.cpp
index 0cefa6e3283fd96bbaa9ad76a17763d7eb7ed225..129e30e3fa31907a8628e6fac86502b94b5aa9c2 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.modifiers/ErrorConditionEnum.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.modifiers/ErrorConditionEnum.pass.cpp
@@ -15,7 +15,7 @@
 #include <system_error>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::error_condition ec;
@@ -23,4 +23,6 @@ int main()
         assert(ec.value() == static_cast<int>(std::errc::not_enough_memory));
         assert(ec.category() == std::generic_category());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.modifiers/assign.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.modifiers/assign.pass.cpp
index 44ff3f67eff0e5d5aa0fb9173b84bb394ff01883..a0e27ee5e77134b8cf8c843ca7419f4180eab155 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.modifiers/assign.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.modifiers/assign.pass.cpp
@@ -15,7 +15,7 @@
 #include <system_error>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::error_condition ec;
@@ -29,4 +29,6 @@ int main()
         assert(ec.value() == 8);
         assert(ec.category() == std::generic_category());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.modifiers/clear.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.modifiers/clear.pass.cpp
index 9dd5bf3035f1f3a318d6ca29a33f4b640ea00460..5de51aa954a6e5e0018315813b4850a935b06222 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.modifiers/clear.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.modifiers/clear.pass.cpp
@@ -15,7 +15,7 @@
 #include <system_error>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::error_condition ec;
@@ -26,4 +26,6 @@ int main()
         assert(ec.value() == 0);
         assert(ec.category() == std::generic_category());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.nonmembers/lt.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.nonmembers/lt.pass.cpp
index ce57687518ed1aa2af8b60496f5533e8d84b4fc7..f1c24514b60dde9bfda1bebfe8447371183daffa 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.nonmembers/lt.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.nonmembers/lt.pass.cpp
@@ -16,11 +16,13 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         const std::error_condition ec1(6, std::generic_category());
         const std::error_condition ec2(7, std::generic_category());
         assert(ec1 < ec2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.nonmembers/make_error_condition.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.nonmembers/make_error_condition.pass.cpp
index 6f64e49bfe7f1bbbf776ad66c4c859c42ba143ef..e9e65db5965b530d56d2e77196ceddf2d7122f82 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.nonmembers/make_error_condition.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.nonmembers/make_error_condition.pass.cpp
@@ -15,11 +15,13 @@
 #include <system_error>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         const std::error_condition ec1 = std::make_error_condition(std::errc::message_size);
         assert(ec1.value() == static_cast<int>(std::errc::message_size));
         assert(ec1.category() == std::generic_category());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.observers/bool.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.observers/bool.pass.cpp
index 8684393dfd13c62a6a1d43d9e7689a4c78371ca9..bccdf5fb0ac73632dc7f1d6ab00a84e16758fc30 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.observers/bool.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.observers/bool.pass.cpp
@@ -16,7 +16,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         const std::error_condition ec(6, std::generic_category());
@@ -26,4 +26,6 @@ int main()
         const std::error_condition ec(0, std::generic_category());
         assert(!static_cast<bool>(ec));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.observers/category.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.observers/category.pass.cpp
index d5bbc94b302f86c4ba4bdf3f989f0470c77e0a8f..f4710a7226c06f7b2f885b295e1e5fa9abc40884 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.observers/category.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.observers/category.pass.cpp
@@ -15,8 +15,10 @@
 #include <system_error>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::error_condition ec(6, std::generic_category());
     assert(ec.category() == std::generic_category());
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.observers/message.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.observers/message.pass.cpp
index c5fc8c60a95d0d746fb24413aaaad516035ce1cf..e533e84ee4bf69a4885329c29cd52f78fa05c282 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.observers/message.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.observers/message.pass.cpp
@@ -16,8 +16,10 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::error_condition ec(6, std::generic_category());
     assert(ec.message() == std::generic_category().message(6));
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.observers/value.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.observers/value.pass.cpp
index 03038e1c83072ea7706b356a7883d36650df124a..d78b1787492ba9c6cff52b17fb04f2618d9bdd48 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.observers/value.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.observers/value.pass.cpp
@@ -15,8 +15,10 @@
 #include <system_error>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::error_condition ec(6, std::system_category());
     assert(ec.value() == 6);
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.overview/types.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.overview/types.pass.cpp
index f6376d523e375c686f5d9e1e00cd55d2d2dfa395..85a0155d75da66acb4f60e73401913d36ae463da 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.overview/types.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.errcondition/syserr.errcondition.overview/types.pass.cpp
@@ -14,9 +14,11 @@
 #include <system_error>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     std::error_condition x = std::errc(0);
     TEST_IGNORE_NODISCARD  x.category();   // returns a std::error_condition &
     TEST_IGNORE_NODISCARD  x.message();    // returns a std::string
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.hash/enabled_hash.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.hash/enabled_hash.pass.cpp
index 6be7b4e9c126df1cfd5bcfb52ff132092b897f73..c127e900a1ce97edb811a1944bd36352f4a8ed70 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.hash/enabled_hash.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.hash/enabled_hash.pass.cpp
@@ -17,10 +17,12 @@
 
 #include "poisoned_hash_helper.hpp"
 
-int main() {
+int main(int, char**) {
   test_library_hash_specializations_available();
   {
     test_hash_enabled_for_type<std::error_code>();
     test_hash_enabled_for_type<std::error_condition>();
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.hash/error_code.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.hash/error_code.pass.cpp
index 0158f3ff31d4ffc5088668b42198babb1afdeb10..f8c09775f232953e4418ce98e6564c86df4dd62e 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.hash/error_code.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.hash/error_code.pass.cpp
@@ -36,9 +36,11 @@ test(int i)
     ((void)result); // Prevent unused warning
 }
 
-int main()
+int main(int, char**)
 {
     test(0);
     test(2);
     test(10);
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.hash/error_condition.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.hash/error_condition.pass.cpp
index d651e6d5c6d4e4019f5dd17c2f4a13f9b01f8e3b..b9b0057b98fb671d31d41ceb26cf4acb2dad8f42 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.hash/error_condition.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.hash/error_condition.pass.cpp
@@ -36,9 +36,11 @@ test(int i)
     ((void)result); // Prevent unused warning
 }
 
-int main()
+int main(int, char**)
 {
     test(0);
     test(2);
     test(10);
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.syserr/nothing_to_do.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.syserr/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.syserr/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.syserr/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.syserr/syserr.syserr.members/ctor_error_code.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.syserr/syserr.syserr.members/ctor_error_code.pass.cpp
index 4d59735fe94cdc1653058cf7d5c23edc9eac35a3..3e721c2d2e2cab5ac30fcaddf0c9686209b6e308 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.syserr/syserr.syserr.members/ctor_error_code.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.syserr/syserr.syserr.members/ctor_error_code.pass.cpp
@@ -18,11 +18,13 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::system_error se(static_cast<int>(std::errc::not_a_directory),
                          std::generic_category(), "some text");
     assert(se.code() == std::make_error_code(std::errc::not_a_directory));
     std::string what_message(se.what());
     assert(what_message.find("Not a directory") != std::string::npos);
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.syserr/syserr.syserr.members/ctor_error_code_const_char_pointer.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.syserr/syserr.syserr.members/ctor_error_code_const_char_pointer.pass.cpp
index c2b229a9df9c368ec7c18fa0db411dfaaff44f31..d15ff75bf9c3c04a7ae342ff2d5e6718483bd4aa 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.syserr/syserr.syserr.members/ctor_error_code_const_char_pointer.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.syserr/syserr.syserr.members/ctor_error_code_const_char_pointer.pass.cpp
@@ -18,7 +18,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::string what_arg("test message");
     std::system_error se(make_error_code(std::errc::not_a_directory), what_arg.c_str());
@@ -26,4 +26,6 @@ int main()
     std::string what_message(se.what());
     assert(what_message.find(what_arg) != std::string::npos);
     assert(what_message.find("Not a directory") != std::string::npos);
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.syserr/syserr.syserr.members/ctor_error_code_string.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.syserr/syserr.syserr.members/ctor_error_code_string.pass.cpp
index adca00d1eb63532849ab315b2bbb5882f2951245..8e2b078005cae07f669038f7caa9e0d1f64d9a14 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.syserr/syserr.syserr.members/ctor_error_code_string.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.syserr/syserr.syserr.members/ctor_error_code_string.pass.cpp
@@ -18,7 +18,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::string what_arg("test message");
     std::system_error se(make_error_code(std::errc::not_a_directory), what_arg);
@@ -26,4 +26,6 @@ int main()
     std::string what_message(se.what());
     assert(what_message.find(what_arg) != std::string::npos);
     assert(what_message.find("Not a directory") != std::string::npos);
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.syserr/syserr.syserr.members/ctor_int_error_category.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.syserr/syserr.syserr.members/ctor_int_error_category.pass.cpp
index d77d20cfe3c05514fb4ec48219097ed0edc95f8b..b1ac08e666d3ef3ad10fe1b028378ccb0ad960b9 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.syserr/syserr.syserr.members/ctor_int_error_category.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.syserr/syserr.syserr.members/ctor_int_error_category.pass.cpp
@@ -18,11 +18,13 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::system_error se(static_cast<int>(std::errc::not_a_directory),
                          std::generic_category());
     assert(se.code() == std::make_error_code(std::errc::not_a_directory));
     std::string what_message(se.what());
     assert(what_message.find("Not a directory") != std::string::npos);
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.syserr/syserr.syserr.members/ctor_int_error_category_const_char_pointer.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.syserr/syserr.syserr.members/ctor_int_error_category_const_char_pointer.pass.cpp
index 789fed6b62f98b0c2df1c78a2a18eae2ebfc7423..a6d24326783a3cd8af6ac5f4134fafbe05272b5b 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.syserr/syserr.syserr.members/ctor_int_error_category_const_char_pointer.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.syserr/syserr.syserr.members/ctor_int_error_category_const_char_pointer.pass.cpp
@@ -18,7 +18,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::string what_arg("test message");
     std::system_error se(static_cast<int>(std::errc::not_a_directory),
@@ -27,4 +27,6 @@ int main()
     std::string what_message(se.what());
     assert(what_message.find(what_arg) != std::string::npos);
     assert(what_message.find("Not a directory") != std::string::npos);
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.syserr/syserr.syserr.members/ctor_int_error_category_string.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.syserr/syserr.syserr.members/ctor_int_error_category_string.pass.cpp
index 29df242f0e26995451ffca14ebd149a10f5290a4..913c675b9a16bd69407efff45647a9f439826220 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.syserr/syserr.syserr.members/ctor_int_error_category_string.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.syserr/syserr.syserr.members/ctor_int_error_category_string.pass.cpp
@@ -18,7 +18,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::string what_arg("test message");
     std::system_error se(static_cast<int>(std::errc::not_a_directory),
@@ -27,4 +27,6 @@ int main()
     std::string what_message(se.what());
     assert(what_message.find(what_arg) != std::string::npos);
     assert(what_message.find("Not a directory") != std::string::npos);
+
+  return 0;
 }
diff --git a/libcxx/test/std/diagnostics/syserr/syserr.syserr/syserr.syserr.overview/nothing_to_do.pass.cpp b/libcxx/test/std/diagnostics/syserr/syserr.syserr/syserr.syserr.overview/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/diagnostics/syserr/syserr.syserr/syserr.syserr.overview/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/diagnostics/syserr/syserr.syserr/syserr.syserr.overview/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/algorithms/alg.search/search.pass.cpp b/libcxx/test/std/experimental/algorithms/alg.search/search.pass.cpp
index 4faa6549ebbe0f57bdcd3cfb9254a8154785e87f..45b1f09729b64ddc260eeec021d397e82dc4803f 100644
--- a/libcxx/test/std/experimental/algorithms/alg.search/search.pass.cpp
+++ b/libcxx/test/std/experimental/algorithms/alg.search/search.pass.cpp
@@ -35,11 +35,13 @@ struct MySearcher {
 };
 
 
-int main() {
+int main(int, char**) {
     typedef int * RI;
     static_assert((std::is_same<RI, decltype(std::experimental::search(RI(), RI(), MySearcher()))>::value), "" );
 
     RI it(nullptr);
     assert(it == std::experimental::search(it, it, MySearcher()));
     assert(searcher_called == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/filesystem/fs.req.macros/feature_macro.pass.cpp b/libcxx/test/std/experimental/filesystem/fs.req.macros/feature_macro.pass.cpp
index 6c216bd20d3ada6938bdd0881a8598044d2836b4..595162d309aa3d4bb1b56f6e257463a52bd0968b 100644
--- a/libcxx/test/std/experimental/filesystem/fs.req.macros/feature_macro.pass.cpp
+++ b/libcxx/test/std/experimental/filesystem/fs.req.macros/feature_macro.pass.cpp
@@ -25,4 +25,6 @@
 #endif
 #endif
 
-int main() { }
+int main(int, char**) { 
+  return 0;
+}
diff --git a/libcxx/test/std/experimental/filesystem/fs.req.namespace/namespace.pass.cpp b/libcxx/test/std/experimental/filesystem/fs.req.namespace/namespace.pass.cpp
index 5e1920f893507682031add17d2e238a4d9888345..87086d429589639468b44324189f372d977c0c78 100644
--- a/libcxx/test/std/experimental/filesystem/fs.req.namespace/namespace.pass.cpp
+++ b/libcxx/test/std/experimental/filesystem/fs.req.namespace/namespace.pass.cpp
@@ -15,9 +15,11 @@
 #include <experimental/filesystem>
 #include <type_traits>
 
-int main() {
+int main(int, char**) {
   static_assert(std::is_same<
           std::experimental::filesystem::path,
           std::experimental::filesystem::v1::path
       >::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore/default.pass.cpp b/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore/default.pass.cpp
index 21780ab8076bff47fab14e1a5cd4dbf927032b12..35c5e50bbe721acd7f2412663a4b023c68388967 100644
--- a/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore/default.pass.cpp
+++ b/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore/default.pass.cpp
@@ -121,7 +121,9 @@ test2()
     do_search(Iter1(ij), Iter1(ij+sj), Iter2(ik), Iter2(ik+sk), Iter1(ij+6));
 }
 
-int main() {
+int main(int, char**) {
     test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
     test2<random_access_iterator<const char*>, random_access_iterator<const char*> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore/hash.pass.cpp b/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore/hash.pass.cpp
index c1546706ec390e9c626ca5e95f3b7ad430ee9969..245b3ddfc7f92d6ca0a575b05bcf21a57a9bbd7d 100644
--- a/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore/hash.pass.cpp
+++ b/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore/hash.pass.cpp
@@ -117,7 +117,9 @@ test2()
     do_search(Iter1(ih), Iter1(ih+sh), Iter2(ii), Iter2(ii+3), Iter1(ih+3),  sh*3);
 }
 
-int main() {
+int main(int, char**) {
     test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
     test2<random_access_iterator<const char*>, random_access_iterator<const char*> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore/hash.pred.pass.cpp b/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore/hash.pred.pass.cpp
index 0614cb98731cd7c4906d7accc5cec53746b688bc..ad90954758e3803446c5739ee40625f52f591589 100644
--- a/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore/hash.pred.pass.cpp
+++ b/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore/hash.pred.pass.cpp
@@ -135,7 +135,9 @@ test2()
     do_search(Iter1(ih), Iter1(ih+sh), Iter2(ii), Iter2(ii+3), Iter1(ih+3),  sh*3);
 }
 
-int main() {
+int main(int, char**) {
     test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
     test2<random_access_iterator<const char*>, random_access_iterator<const char*> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore/pred.pass.cpp b/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore/pred.pass.cpp
index 12ab20cdd4424b7cb9b2f1654a604f9263d12762..a361b90b85267414a5674493f4b2bace6d20d860 100644
--- a/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore/pred.pass.cpp
+++ b/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore/pred.pass.cpp
@@ -126,7 +126,9 @@ test2()
     do_search(Iter1(ih), Iter1(ih+sh), Iter2(ii), Iter2(ii+3), Iter1(ih+3),  sh*3);
 }
 
-int main() {
+int main(int, char**) {
     test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
     test2<random_access_iterator<const char*>, random_access_iterator<const char*> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore_horspool/default.pass.cpp b/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore_horspool/default.pass.cpp
index 0cd6174afce1cdd2aeb89f003ac3a718210d77c2..95426f81c88f5475525fad7ef8b0989c3fd4ac11 100644
--- a/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore_horspool/default.pass.cpp
+++ b/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore_horspool/default.pass.cpp
@@ -121,7 +121,9 @@ test2()
     do_search(Iter1(ij), Iter1(ij+sj), Iter2(ik), Iter2(ik+sk), Iter1(ij+6));
 }
 
-int main() {
+int main(int, char**) {
     test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
     test2<random_access_iterator<const char*>, random_access_iterator<const char*> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore_horspool/hash.pass.cpp b/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore_horspool/hash.pass.cpp
index 0fe8420a5185afc222b47963d7673b819fbf7676..151a0f46b41866050ad730e89995776fe76c5bd5 100644
--- a/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore_horspool/hash.pass.cpp
+++ b/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore_horspool/hash.pass.cpp
@@ -116,7 +116,9 @@ test2()
     do_search(Iter1(ih), Iter1(ih+sh), Iter2(ii), Iter2(ii+3), Iter1(ih+3),  sh*3);
 }
 
-int main() {
+int main(int, char**) {
     test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
     test2<random_access_iterator<const char*>, random_access_iterator<const char*> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore_horspool/hash.pred.pass.cpp b/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore_horspool/hash.pred.pass.cpp
index 916660c1eb06039bce607477172dab731e9340ab..bcdaa87c4a49017130b8f119cbb24382cd1e7ca7 100644
--- a/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore_horspool/hash.pred.pass.cpp
+++ b/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore_horspool/hash.pred.pass.cpp
@@ -129,7 +129,9 @@ test2()
     do_search(Iter1(ih), Iter1(ih+sh), Iter2(ii), Iter2(ii+3), Iter1(ih+3),  sh*3);
 }
 
-int main() {
+int main(int, char**) {
     test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
     test2<random_access_iterator<const char*>, random_access_iterator<const char*> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore_horspool/pred.pass.cpp b/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore_horspool/pred.pass.cpp
index 3cdac5ffd374a9bccd6f690c6f1cb837c36a53dc..06a93c5d7b7119b7b250f4ee7c831c84fe61f116 100644
--- a/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore_horspool/pred.pass.cpp
+++ b/libcxx/test/std/experimental/func/func.searchers/func.searchers.boyer_moore_horspool/pred.pass.cpp
@@ -123,7 +123,9 @@ test2()
     do_search(Iter1(ih), Iter1(ih+sh), Iter2(ii), Iter2(ii+3), Iter1(ih+3),  sh*3);
 }
 
-int main() {
+int main(int, char**) {
     test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
     test2<random_access_iterator<const char*>, random_access_iterator<const char*> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/func/func.searchers/func.searchers.default/default.pass.cpp b/libcxx/test/std/experimental/func/func.searchers/func.searchers.default/default.pass.cpp
index 524bba17d402919924277eb744d279b48743fdc9..b3f6c66387fcbe27461dbe459c39050c5769d8d3 100644
--- a/libcxx/test/std/experimental/func/func.searchers/func.searchers.default/default.pass.cpp
+++ b/libcxx/test/std/experimental/func/func.searchers/func.searchers.default/default.pass.cpp
@@ -82,7 +82,7 @@ test()
     do_search(Iter1(ij), Iter1(ij+sj), Iter2(ik), Iter2(ik+sk), Iter1(ij+6));
 }
 
-int main() {
+int main(int, char**) {
     test<forward_iterator<const int*>, forward_iterator<const int*> >();
     test<forward_iterator<const int*>, bidirectional_iterator<const int*> >();
     test<forward_iterator<const int*>, random_access_iterator<const int*> >();
@@ -92,4 +92,6 @@ int main() {
     test<random_access_iterator<const int*>, forward_iterator<const int*> >();
     test<random_access_iterator<const int*>, bidirectional_iterator<const int*> >();
     test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/func/func.searchers/func.searchers.default/default.pred.pass.cpp b/libcxx/test/std/experimental/func/func.searchers/func.searchers.default/default.pred.pass.cpp
index a4d0b0730a12e4d2d52fbe5ccc8b8a5bb6126969..f1573a2e06728df79fe82feefff1213f6aa5e13e 100644
--- a/libcxx/test/std/experimental/func/func.searchers/func.searchers.default/default.pred.pass.cpp
+++ b/libcxx/test/std/experimental/func/func.searchers/func.searchers.default/default.pred.pass.cpp
@@ -89,7 +89,7 @@ test()
     do_search(Iter1(ih), Iter1(ih+sh), Iter2(ii), Iter2(ii+3), Iter1(ih+3),  sh*3);
 }
 
-int main() {
+int main(int, char**) {
     test<forward_iterator<const int*>, forward_iterator<const int*> >();
     test<forward_iterator<const int*>, bidirectional_iterator<const int*> >();
     test<forward_iterator<const int*>, random_access_iterator<const int*> >();
@@ -99,4 +99,6 @@ int main() {
     test<random_access_iterator<const int*>, forward_iterator<const int*> >();
     test<random_access_iterator<const int*>, bidirectional_iterator<const int*> >();
     test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/func/func.searchers/func.searchers.default/func.searchers.default.creation/make_default_searcher.pass.cpp b/libcxx/test/std/experimental/func/func.searchers/func.searchers.default/func.searchers.default.creation/make_default_searcher.pass.cpp
index 3bf33c808b681d6cf979755c17a38d4b5e6d7119..5187569ecf3824bbd097a3a1d2fe918044c0cef5 100644
--- a/libcxx/test/std/experimental/func/func.searchers/func.searchers.default/func.searchers.default.creation/make_default_searcher.pass.cpp
+++ b/libcxx/test/std/experimental/func/func.searchers/func.searchers.default/func.searchers.default.creation/make_default_searcher.pass.cpp
@@ -67,7 +67,7 @@ test()
     do_search(Iter1(ij), Iter1(ij+sj), Iter2(ik), Iter2(ik+sk), Iter1(ij+6));
 }
 
-int main() {
+int main(int, char**) {
     test<forward_iterator<const int*>, forward_iterator<const int*> >();
     test<forward_iterator<const int*>, bidirectional_iterator<const int*> >();
     test<forward_iterator<const int*>, random_access_iterator<const int*> >();
@@ -77,4 +77,6 @@ int main() {
     test<random_access_iterator<const int*>, forward_iterator<const int*> >();
     test<random_access_iterator<const int*>, bidirectional_iterator<const int*> >();
     test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/func/func.searchers/func.searchers.default/func.searchers.default.creation/make_default_searcher.pred.pass.cpp b/libcxx/test/std/experimental/func/func.searchers/func.searchers.default/func.searchers.default.creation/make_default_searcher.pred.pass.cpp
index a827f3d2a4b0e9a5b0529acc13e43aebc28e8b9c..a6996437ec1f3685870982afd8d5cf36b915d49f 100644
--- a/libcxx/test/std/experimental/func/func.searchers/func.searchers.default/func.searchers.default.creation/make_default_searcher.pred.pass.cpp
+++ b/libcxx/test/std/experimental/func/func.searchers/func.searchers.default/func.searchers.default.creation/make_default_searcher.pred.pass.cpp
@@ -74,7 +74,7 @@ test()
     do_search(Iter1(ih), Iter1(ih+sh), Iter2(ii), Iter2(ii+3), Iter1(ih+3),  sh*3);
 }
 
-int main() {
+int main(int, char**) {
     test<forward_iterator<const int*>, forward_iterator<const int*> >();
     test<forward_iterator<const int*>, bidirectional_iterator<const int*> >();
     test<forward_iterator<const int*>, random_access_iterator<const int*> >();
@@ -84,4 +84,6 @@ int main() {
     test<random_access_iterator<const int*>, forward_iterator<const int*> >();
     test<random_access_iterator<const int*>, bidirectional_iterator<const int*> >();
     test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/func/func.searchers/nothing_to_do.pass.cpp b/libcxx/test/std/experimental/func/func.searchers/nothing_to_do.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/std/experimental/func/func.searchers/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/experimental/func/func.searchers/nothing_to_do.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/func/header.functional.synop/includes.pass.cpp b/libcxx/test/std/experimental/func/header.functional.synop/includes.pass.cpp
index 805d8c8fdc9d115c91ab48e79de3451bd9168d2a..4b913c2d780e194ad02aad2fe2a5b044c517c824 100644
--- a/libcxx/test/std/experimental/func/header.functional.synop/includes.pass.cpp
+++ b/libcxx/test/std/experimental/func/header.functional.synop/includes.pass.cpp
@@ -14,7 +14,9 @@
 
 #include <experimental/functional>
 
-int main()
+int main(int, char**)
 {
   std::function<int(int)> x;
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/func/nothing_to_do.pass.cpp b/libcxx/test/std/experimental/func/nothing_to_do.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/std/experimental/func/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/experimental/func/nothing_to_do.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/iterator/nothing_to_do.pass.cpp b/libcxx/test/std/experimental/iterator/nothing_to_do.pass.cpp
index 85149549f17dce58b073b283635d3557541c788f..782c1a03ee553389dd465bc3a9c9735198637d5b 100644
--- a/libcxx/test/std/experimental/iterator/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/experimental/iterator/nothing_to_do.pass.cpp
@@ -8,4 +8,6 @@
 
 #include <experimental/iterator>
 
-int main () {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/std/experimental/iterator/ostream.joiner/ostream.joiner.cons/ostream_joiner.cons.pass.cpp b/libcxx/test/std/experimental/iterator/ostream.joiner/ostream.joiner.cons/ostream_joiner.cons.pass.cpp
index 869af67bc62760d88cb1d8955775c463111f0135..4e3994f956045fddd67d9ee28f5547653893cfdc 100644
--- a/libcxx/test/std/experimental/iterator/ostream.joiner/ostream.joiner.cons/ostream_joiner.cons.pass.cpp
+++ b/libcxx/test/std/experimental/iterator/ostream.joiner/ostream.joiner.cons/ostream_joiner.cons.pass.cpp
@@ -24,7 +24,7 @@
 
 namespace exp = std::experimental;
 
-int main () {
+int main(int, char**) {
     const char eight = '8';
     const std::string nine = "9";
     const std::wstring ten = L"10";
@@ -54,4 +54,6 @@ int main () {
     { exp::ostream_joiner<std::wstring, wchar_t> oj(std::wcout, ten); }
     { exp::ostream_joiner<int, wchar_t>          oj(std::wcout, eleven); }
 
-    }
+    
+  return 0;
+}
diff --git a/libcxx/test/std/experimental/iterator/ostream.joiner/ostream.joiner.creation/make_ostream_joiner.pass.cpp b/libcxx/test/std/experimental/iterator/ostream.joiner/ostream.joiner.creation/make_ostream_joiner.pass.cpp
index b8e98b9048ff88811b7714cb171820b190847c7b..a2dab9afbb603cf2e456ffaa2bb746ddf3bb7e2d 100644
--- a/libcxx/test/std/experimental/iterator/ostream.joiner/ostream.joiner.creation/make_ostream_joiner.pass.cpp
+++ b/libcxx/test/std/experimental/iterator/ostream.joiner/ostream.joiner.creation/make_ostream_joiner.pass.cpp
@@ -39,7 +39,7 @@ void test (Delim &&d, Iter first, Iter last, const CharT *expected ) {
     assert(sstream.str() == expected);
     }
 
-int main () {
+int main(int, char**) {
     const char chars[] = "0123456789";
     const int  ints [] = { 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 };
 
@@ -49,4 +49,6 @@ int main () {
     test('x', ints,  ints+10,  "10x11x12x13x14x15x16x17x18x19");
     test("Z", chars, chars+10, "0Z1Z2Z3Z4Z5Z6Z7Z8Z9");
     test("z", ints,  ints+10,  "10z11z12z13z14z15z16z17z18z19");
-    }
+    
+  return 0;
+}
diff --git a/libcxx/test/std/experimental/iterator/ostream.joiner/ostream.joiner.ops/ostream_joiner.op.assign.pass.cpp b/libcxx/test/std/experimental/iterator/ostream.joiner/ostream.joiner.ops/ostream_joiner.op.assign.pass.cpp
index 674f2863d6a156642a4cc6cf6fdb23417afcd40e..c1bf74afcd5ef2e0b368d725f7bff18904940aab 100644
--- a/libcxx/test/std/experimental/iterator/ostream.joiner/ostream.joiner.ops/ostream_joiner.op.assign.pass.cpp
+++ b/libcxx/test/std/experimental/iterator/ostream.joiner/ostream.joiner.ops/ostream_joiner.op.assign.pass.cpp
@@ -67,7 +67,7 @@ void test (Delim &&d, Iter first, Iter last, const CharT *expected ) {
     assert(sstream.str() == expected);
     }
 
-int main () {
+int main(int, char**) {
 {
     const char chars[] = "0123456789";
     const int  ints [] = { 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 };
@@ -116,4 +116,6 @@ int main () {
     test(mutating_delimiter(), chars, chars+10, L"0 1!2\"3#4$5%6&7'8(9");
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/iterator/ostream.joiner/ostream.joiner.ops/ostream_joiner.op.postincrement.pass.cpp b/libcxx/test/std/experimental/iterator/ostream.joiner/ostream.joiner.ops/ostream_joiner.op.postincrement.pass.cpp
index 69d2258b13e8259709d83ec60be1543209dc2dfc..095020eb63ca97a21f68b571bad54a605e96cfb9 100644
--- a/libcxx/test/std/experimental/iterator/ostream.joiner/ostream.joiner.ops/ostream_joiner.op.postincrement.pass.cpp
+++ b/libcxx/test/std/experimental/iterator/ostream.joiner/ostream.joiner.ops/ostream_joiner.op.postincrement.pass.cpp
@@ -31,7 +31,7 @@ void test ( exp::ostream_joiner<Delim, CharT, Traits> &oj ) {
     assert( &ret == &oj );
     }
 
-int main () {
+int main(int, char**) {
 
     { exp::ostream_joiner<char>         oj(std::cout, '8');                 test(oj); }
     { exp::ostream_joiner<std::string>  oj(std::cout, std::string("9"));    test(oj); }
@@ -42,4 +42,6 @@ int main () {
     { exp::ostream_joiner<std::string, wchar_t>  oj(std::wcout, std::string("9"));    test(oj); }
     { exp::ostream_joiner<std::wstring, wchar_t> oj(std::wcout, std::wstring(L"10")); test(oj); }
     { exp::ostream_joiner<int, wchar_t>          oj(std::wcout, 11);                  test(oj); }
-    }
+    
+  return 0;
+}
diff --git a/libcxx/test/std/experimental/iterator/ostream.joiner/ostream.joiner.ops/ostream_joiner.op.pretincrement.pass.cpp b/libcxx/test/std/experimental/iterator/ostream.joiner/ostream.joiner.ops/ostream_joiner.op.pretincrement.pass.cpp
index e7210ac721fe996c65cc16102d0c01d022713f2c..2e305c2ff7c7e38d914fac22964d192504c0735a 100644
--- a/libcxx/test/std/experimental/iterator/ostream.joiner/ostream.joiner.ops/ostream_joiner.op.pretincrement.pass.cpp
+++ b/libcxx/test/std/experimental/iterator/ostream.joiner/ostream.joiner.ops/ostream_joiner.op.pretincrement.pass.cpp
@@ -31,7 +31,7 @@ void test ( exp::ostream_joiner<Delim, CharT, Traits> &oj ) {
     assert( &ret == &oj );
     }
 
-int main () {
+int main(int, char**) {
 
     { exp::ostream_joiner<char>         oj(std::cout, '8');                 test(oj); }
     { exp::ostream_joiner<std::string>  oj(std::cout, std::string("9"));    test(oj); }
@@ -42,4 +42,6 @@ int main () {
     { exp::ostream_joiner<std::string, wchar_t>  oj(std::wcout, std::string("9"));    test(oj); }
     { exp::ostream_joiner<std::wstring, wchar_t> oj(std::wcout, std::wstring(L"10")); test(oj); }
     { exp::ostream_joiner<int, wchar_t>          oj(std::wcout, 11);                  test(oj); }
-    }
+    
+  return 0;
+}
diff --git a/libcxx/test/std/experimental/iterator/ostream.joiner/ostream.joiner.ops/ostream_joiner.op.star.pass.cpp b/libcxx/test/std/experimental/iterator/ostream.joiner/ostream.joiner.ops/ostream_joiner.op.star.pass.cpp
index d9661510bee630c35905409eab51c473eb9f764a..74bf9c3091174267b16c01c7c362c05ee62cd324 100644
--- a/libcxx/test/std/experimental/iterator/ostream.joiner/ostream.joiner.ops/ostream_joiner.op.star.pass.cpp
+++ b/libcxx/test/std/experimental/iterator/ostream.joiner/ostream.joiner.ops/ostream_joiner.op.star.pass.cpp
@@ -31,7 +31,7 @@ void test ( exp::ostream_joiner<Delim, CharT, Traits> &oj ) {
     assert( &ret == &oj );
     }
 
-int main () {
+int main(int, char**) {
 
     { exp::ostream_joiner<char>         oj(std::cout, '8');                 test(oj); }
     { exp::ostream_joiner<std::string>  oj(std::cout, std::string("9"));    test(oj); }
@@ -42,4 +42,6 @@ int main () {
     { exp::ostream_joiner<std::string, wchar_t>  oj(std::wcout, std::string("9"));    test(oj); }
     { exp::ostream_joiner<std::wstring, wchar_t> oj(std::wcout, std::wstring(L"10")); test(oj); }
     { exp::ostream_joiner<int, wchar_t>          oj(std::wcout, 11);                  test(oj); }
-    }
+    
+  return 0;
+}
diff --git a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.capacity/operator_bool.pass.cpp b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.capacity/operator_bool.pass.cpp
index 99786488114cd488aa00fc2d31d2c3810fc4231c..b3fbd27632e2c4b1898ebd2e3a2a90dc8718feef 100644
--- a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.capacity/operator_bool.pass.cpp
+++ b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.capacity/operator_bool.pass.cpp
@@ -50,8 +50,10 @@ void do_test() {
   }
 }
 
-int main()
+int main(int, char**)
 {
   do_test<coro::coroutine_handle<>>();
   do_test<coro::coroutine_handle<int>>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.compare/equal_comp.pass.cpp b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.compare/equal_comp.pass.cpp
index 8b205ab89159a50503c95030c47ce2cf876e9bbe..f6290fdfa9921bf5e3c5700c5632930ff8fdf1f8 100644
--- a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.compare/equal_comp.pass.cpp
+++ b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.compare/equal_comp.pass.cpp
@@ -44,7 +44,7 @@ void do_test(uintptr_t LHSVal, uintptr_t RHSVal) {
   }
 }
 
-int main()
+int main(int, char**)
 {
   std::pair<uintptr_t, uintptr_t> const TestCases[] = {
       {0, 0},
@@ -56,4 +56,6 @@ int main()
     do_test<coro::coroutine_handle<>>(TC.first, TC.second);
     do_test<coro::coroutine_handle<int>>(TC.first, TC.second);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.compare/less_comp.pass.cpp b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.compare/less_comp.pass.cpp
index 428b2e4b09e4b5cc9395aaed06ced3d50749c902..8152b53f988d52ceba930cf330181a5c2e223e0c 100644
--- a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.compare/less_comp.pass.cpp
+++ b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.compare/less_comp.pass.cpp
@@ -53,7 +53,7 @@ void do_test(uintptr_t LHSVal, uintptr_t RHSVal) {
   }
 }
 
-int main()
+int main(int, char**)
 {
   std::pair<uintptr_t, uintptr_t> const TestCases[] = {
       {0, 0},
@@ -65,4 +65,6 @@ int main()
     do_test<coro::coroutine_handle<>>(TC.first, TC.second);
     do_test<coro::coroutine_handle<int>>(TC.first, TC.second);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.completion/done.pass.cpp b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.completion/done.pass.cpp
index 39c279fe82d0efe6ce88eca0bf3c25ef05168460..14ac3976e1936fa1198465dd9fa5eb78fad2c120 100644
--- a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.completion/done.pass.cpp
+++ b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.completion/done.pass.cpp
@@ -36,8 +36,10 @@ void do_test(coro::coroutine_handle<Promise> const& H) {
   }
 }
 
-int main()
+int main(int, char**)
 {
   do_test(coro::coroutine_handle<>{});
   do_test(coro::coroutine_handle<int>{});
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.con/assign.pass.cpp b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.con/assign.pass.cpp
index da14b4b60f9566d9105082263bb89a7ff6d68c19..2af0b717ea698b4e431be46599e358347f87077d 100644
--- a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.con/assign.pass.cpp
+++ b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.con/assign.pass.cpp
@@ -46,8 +46,10 @@ void do_test() {
   }
 }
 
-int main()
+int main(int, char**)
 {
   do_test<coro::coroutine_handle<>>();
   do_test<coro::coroutine_handle<int>>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.con/construct.pass.cpp b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.con/construct.pass.cpp
index 84fa9314dab8b4b13d61bb381234847141c00f48..7832856c1cf64c34850c8595acb4339db98c3e8b 100644
--- a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.con/construct.pass.cpp
+++ b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.con/construct.pass.cpp
@@ -45,8 +45,10 @@ void do_test() {
   }
 }
 
-int main()
+int main(int, char**)
 {
   do_test<coro::coroutine_handle<>>();
   do_test<coro::coroutine_handle<int>>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.export/address.pass.cpp b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.export/address.pass.cpp
index 6559ad52d7faa7048e5f7a89d53467052509a0b7..3c63dbbeb30e7429a12d0ada660e8e8b9f9eeddf 100644
--- a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.export/address.pass.cpp
+++ b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.export/address.pass.cpp
@@ -43,8 +43,10 @@ void do_test() {
   }
 }
 
-int main()
+int main(int, char**)
 {
   do_test<coro::coroutine_handle<>>();
   do_test<coro::coroutine_handle<int>>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.export/from_address.fail.cpp b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.export/from_address.fail.cpp
index 9e9490a3ee7b3c26d37da77dd980297b39420db0..e9dd0678f4fdcdc4b5a97a9c1b4d54ba62e7f7f8 100644
--- a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.export/from_address.fail.cpp
+++ b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.export/from_address.fail.cpp
@@ -26,7 +26,7 @@
 
 namespace coro = std::experimental;
 
-int main()
+int main(int, char**)
 {
   {
     using H = coro::coroutine_handle<>;
@@ -42,4 +42,6 @@ int main()
     // expected-error@experimental/coroutine:* 1 {{coroutine_handle<promise_type>::from_address cannot be called with non-void pointers}}
     H::from_address((int*)nullptr); // expected-note {{requested here}}
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.export/from_address.pass.cpp b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.export/from_address.pass.cpp
index e856ca12ed65dcf6029b1c529a5b4fbc978e96e3..9c4a647e5fc8d8e6d1557470a068d0ec910c9061 100644
--- a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.export/from_address.pass.cpp
+++ b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.export/from_address.pass.cpp
@@ -38,8 +38,10 @@ void do_test() {
   }
 }
 
-int main()
+int main(int, char**)
 {
   do_test<coro::coroutine_handle<>>();
   do_test<coro::coroutine_handle<int>>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.hash/hash.pass.cpp b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.hash/hash.pass.cpp
index 59c20b84930fd3c3f16bfa8c95dbcdc850205f74..612380b6de026139d325271096ff399b3b6fc82e 100644
--- a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.hash/hash.pass.cpp
+++ b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.hash/hash.pass.cpp
@@ -47,7 +47,7 @@ void do_test(uintptr_t LHSVal, uintptr_t RHSVal) {
   }
 }
 
-int main()
+int main(int, char**)
 {
   std::pair<uintptr_t, uintptr_t> const TestCases[] = {
       {0, 0},
@@ -59,4 +59,6 @@ int main()
     do_test<coro::coroutine_handle<>>(TC.first, TC.second);
     do_test<coro::coroutine_handle<int>>(TC.first, TC.second);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.noop/noop_coroutine.pass.cpp b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.noop/noop_coroutine.pass.cpp
index eabf03ef0c7ae013d03346bb1b573ca90572825b..27b83ce02e15f48181864658e1115468df61fc20 100644
--- a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.noop/noop_coroutine.pass.cpp
+++ b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.noop/noop_coroutine.pass.cpp
@@ -44,7 +44,7 @@ static_assert(std::is_same<decltype(coro::noop_coroutine()), coro::noop_coroutin
 // // 18.11.2.10 noop address
 // constexpr void* address() const noexcept;
 
-int main()
+int main(int, char**)
 {
   auto h = coro::noop_coroutine();
   coro::coroutine_handle<> base = h;
@@ -65,10 +65,12 @@ int main()
   assert(h.address() == base.address());
   assert(h.address() != nullptr);
   assert(coro::coroutine_handle<>::from_address(h.address()) == base);
+
+  return 0;
 }
 
 #else
 
-int main() {}
+int main(int, char**) { return 0; }
 
 #endif //  __has_builtin(__builtin_coro_noop)
diff --git a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.prom/promise.pass.cpp b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.prom/promise.pass.cpp
index 87e182e03dcb3fe6d8925c4ca6e5f887c5957702..0f81fdca85b171828f489efef8e0442773a42ca7 100644
--- a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.prom/promise.pass.cpp
+++ b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.prom/promise.pass.cpp
@@ -75,9 +75,11 @@ void do_test(coro::coroutine_handle<Promise>&& H) {
   }
 }
 
-int main()
+int main(int, char**)
 {
   do_test(coro::coroutine_handle<int>{});
   do_test(coro::coroutine_handle<const int>{});
   do_runtime_test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.resumption/destroy.pass.cpp b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.resumption/destroy.pass.cpp
index 693e0518fddb920b107efc02593ae71e3613bd9e..72ba9fee637e7257ae2ba2b4e1765585321eedc4 100644
--- a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.resumption/destroy.pass.cpp
+++ b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.resumption/destroy.pass.cpp
@@ -53,8 +53,10 @@ void do_test(coro::coroutine_handle<Promise>&& H) {
   }
 }
 
-int main()
+int main(int, char**)
 {
   do_test(coro::coroutine_handle<>{});
   do_test(coro::coroutine_handle<int>{});
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.resumption/resume.pass.cpp b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.resumption/resume.pass.cpp
index 85d84a4351ee42493413a4966eddafa5020a24b7..a3804ae43a5dc4d084d8ec8a1422df91b0c9dfa8 100644
--- a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.resumption/resume.pass.cpp
+++ b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/coroutine.handle.resumption/resume.pass.cpp
@@ -72,8 +72,10 @@ void do_test(coro::coroutine_handle<Promise>&& H) {
   }
 }
 
-int main()
+int main(int, char**)
 {
   do_test(coro::coroutine_handle<>{});
   do_test(coro::coroutine_handle<int>{});
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/void_handle.pass.cpp b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/void_handle.pass.cpp
index a2214ba108ce277581b42f8989c66d032c8df089..8536e23d4624ed799181c26258507f0e906cd745 100644
--- a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/void_handle.pass.cpp
+++ b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.handle/void_handle.pass.cpp
@@ -41,10 +41,12 @@ void check_type() {
   static_assert(std::is_same<P, Expect>::value, "");
 };
 
-int main()
+int main(int, char**)
 {
   check_type<A*, A>();
   check_type<int*, A, int>();
   check_type<B*, B>();
   check_type<void, C>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.traits/promise_type.pass.cpp b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.traits/promise_type.pass.cpp
index b06dac41bed4480dfe399fd7ad63c0fcfd1476f9..781f264ffd7ac5dfb6444ac3af0e88f14a0c9cc0 100644
--- a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.traits/promise_type.pass.cpp
+++ b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.traits/promise_type.pass.cpp
@@ -60,7 +60,7 @@ void check_no_type() {
   static_assert(!has_promise_type<Traits>(), "");
 }
 
-int main()
+int main(int, char**)
 {
   {
     check_type<A*, A>();
@@ -73,4 +73,6 @@ int main()
     check_no_type<E>();
     check_no_type<C, int>();
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.trivial.awaitables/suspend_always.pass.cpp b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.trivial.awaitables/suspend_always.pass.cpp
index 93ac47196671bc5b40cad667c785c9b6d41f46a4..89f1619df60370a1f948f78ec6673dbbf10b1d06 100644
--- a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.trivial.awaitables/suspend_always.pass.cpp
+++ b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.trivial.awaitables/suspend_always.pass.cpp
@@ -31,7 +31,7 @@ constexpr bool check_suspend_constexpr() {
   return true;
 }
 
-int main()
+int main(int, char**)
 {
   using H = coro::coroutine_handle<>;
   using S = SuspendT;
@@ -69,4 +69,6 @@ int main()
     // suppress unused warnings for the global constexpr test variable
     ((void)constexpr_sa);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.trivial.awaitables/suspend_never.pass.cpp b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.trivial.awaitables/suspend_never.pass.cpp
index 2ff45941796897ec69673cb9bc30a89007d48ff0..7986b292649d3321fddb8a7d5e91ce85df3b995b 100644
--- a/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.trivial.awaitables/suspend_never.pass.cpp
+++ b/libcxx/test/std/experimental/language.support/support.coroutines/coroutine.trivial.awaitables/suspend_never.pass.cpp
@@ -33,7 +33,7 @@ constexpr bool check_suspend_constexpr() {
 }
 
 
-int main()
+int main(int, char**)
 {
   using H = coro::coroutine_handle<>;
   using S = SuspendT;
@@ -71,4 +71,6 @@ int main()
     // suppress unused warnings for the global constexpr test variable
     ((void)constexpr_sn);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/await_result.pass.cpp b/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/await_result.pass.cpp
index a5ec2075612c3d0cee4672140abd735fbdfd1633..c540ca9fb35378d1af12928e96bcffb03286981a 100644
--- a/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/await_result.pass.cpp
+++ b/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/await_result.pass.cpp
@@ -59,10 +59,12 @@ coro_t f(int n) {
 
 coro_t g() { B val = co_await B{}; }
 
-int main() {
+int main(int, char**) {
   last_value = -1;
   f(0);
   assert(last_value == 0);
   f(1);
   assert(last_value == 42);
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/bool_await_suspend.pass.cpp b/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/bool_await_suspend.pass.cpp
index ea30b89771f19f75216497e520cd9d1bde4f2565..fb15ade8bb2ba1d1650fa3ae853ba3cd0f77f82d 100644
--- a/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/bool_await_suspend.pass.cpp
+++ b/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/bool_await_suspend.pass.cpp
@@ -57,7 +57,7 @@ coro_t g() {
   g_resumed = true;
 }
 
-int main() {
+int main(int, char**) {
   assert(!f_started && !f_resumed && !g_started && !g_resumed);
   auto fret = f();
   assert(f_started && !f_resumed);
@@ -65,4 +65,6 @@ int main() {
   assert(f_started && !f_resumed);
   g();
   assert(g_started && g_resumed);
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/expected.pass.cpp b/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/expected.pass.cpp
index 4358f670038e090912949969f2ecf7a022d57db6..a899092d0347834808a8f2933887b49ef485a7f5 100644
--- a/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/expected.pass.cpp
+++ b/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/expected.pass.cpp
@@ -75,7 +75,7 @@ expected<int> f2() {
   co_return 200;
 }
 
-int main() {
+int main(int, char**) {
   auto c1 = f1();
   assert(f1_started && f1_resumed);
   assert(c1.value() == 100);
@@ -85,4 +85,6 @@ int main() {
   assert(f2_started && !f2_resumed);
   assert(c2.value() == 0);
   assert(c2.error() == 42);
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/fullexpr-dtor.pass.cpp b/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/fullexpr-dtor.pass.cpp
index 62fe61a31756f46697f498f735c99cb6673f057e..87d3c8f9d68ffaa225b89cce18214ac0cfb46601 100644
--- a/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/fullexpr-dtor.pass.cpp
+++ b/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/fullexpr-dtor.pass.cpp
@@ -108,9 +108,11 @@ coro2 d() {
   assert(dtor_called == 1);
 }
 
-int main() {
+int main(int, char**) {
   a();
   b();
   c();
   d();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/generator.pass.cpp b/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/generator.pass.cpp
index e885358d2d8f08816f19ff67a2b69e92bf7bfcc3..84b4deb9ce454a419025cfd6850f9384a50c4f8b 100644
--- a/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/generator.pass.cpp
+++ b/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/generator.pass.cpp
@@ -95,8 +95,10 @@ void test_mini_generator() {
   assert(sum == 10);
 }
 
-int main() {
+int main(int, char**) {
   test_count();
   test_range();
   test_mini_generator();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/go.pass.cpp b/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/go.pass.cpp
index 18e96b680de2b32cd7387a86d4ecd60a907bf411..994bd87d6de445142249c345ef74eae6b9c36271 100644
--- a/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/go.pass.cpp
+++ b/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/go.pass.cpp
@@ -164,7 +164,7 @@ goroutine pusher(channel& left, channel& right)
 const int N = 100;
 channel* c = new channel[N + 1];
 
-int main() {
+int main(int, char**) {
   for (int i = 0; i < N; ++i)
     goroutine::go(pusher(c[i], c[i + 1]));
 
@@ -172,4 +172,6 @@ int main() {
   int result = c[N].sync_pull();
 
   assert(result == 100);
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/multishot_func.pass.cpp b/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/multishot_func.pass.cpp
index 1b7bdd16106d0ed45e79adb0ee32fc8fdefcf134..fed97ea2308dbc2ef3e7323c387cef9c0b5700bc 100644
--- a/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/multishot_func.pass.cpp
+++ b/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/multishot_func.pass.cpp
@@ -80,7 +80,9 @@ int Do(int acc, int n, func<int> f) {
   return acc;
 }
 
-int main() {
+int main(int, char**) {
   int result = Do(1, 10, [](int a, int b) {return a + b;});
   assert(result == 46);
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/oneshot_func.pass.cpp b/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/oneshot_func.pass.cpp
index 567f438daa595d642dcacd30382db72f53b88162..4bab2dd3bf2f9da8fadf8d8b792f023ad7961e25 100644
--- a/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/oneshot_func.pass.cpp
+++ b/libcxx/test/std/experimental/language.support/support.coroutines/end.to.end/oneshot_func.pass.cpp
@@ -72,11 +72,13 @@ float fyield(int x) { yielded_values.push_back(x); return static_cast<float>(x +
 void Do1(func<int> f) { yield(f()); }
 void Do2(func<double> f) { yield(static_cast<int>(f())); }
 
-int main() {
+int main(int, char**) {
   Do1([] { return yield(43); });
   assert((yielded_values == std::vector<int>{43, 44}));
 
   yielded_values = {};
   Do2([] { return fyield(44); });
   assert((yielded_values == std::vector<int>{44, 46}));
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/language.support/support.coroutines/includes.pass.cpp b/libcxx/test/std/experimental/language.support/support.coroutines/includes.pass.cpp
index 8fc7b4cc80bb552dedff824a22515e196c22d847..440ffa113a13f319d19d0831424db2744cb71117 100644
--- a/libcxx/test/std/experimental/language.support/support.coroutines/includes.pass.cpp
+++ b/libcxx/test/std/experimental/language.support/support.coroutines/includes.pass.cpp
@@ -15,10 +15,11 @@
 
 #include <experimental/coroutine>
 
-int main(){
+int main(int, char**) {
   // std::nothrow is not implicitly defined by the compiler when the include is
   // missing, unlike other parts of <new>. Therefore we use std::nothrow to
   // test for #include <new>
   (void)std::nothrow;
 
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.ctor/assign.pass.cpp b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.ctor/assign.pass.cpp
index 885137e762e1203edcaf0f32dcdbd2e098487a4d..35a98b789ef77b346689adc2618b5d1dbd1626f7 100644
--- a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.ctor/assign.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.ctor/assign.pass.cpp
@@ -20,9 +20,11 @@
 
 namespace ex = std::experimental::pmr;
 
-int main()
+int main(int, char**)
 {
     typedef ex::polymorphic_allocator<void> T;
     static_assert(!std::is_copy_assignable<T>::value, "");
     static_assert(!std::is_move_assignable<T>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.ctor/copy.pass.cpp b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.ctor/copy.pass.cpp
index 1500f641d3ffa5ba841c6f887539f93c831dedba..ce3c9be105db9f012c0234d77ac5581bffac0b5c 100644
--- a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.ctor/copy.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.ctor/copy.pass.cpp
@@ -20,7 +20,7 @@
 
 namespace ex = std::experimental::pmr;
 
-int main()
+int main(int, char**)
 {
     typedef ex::polymorphic_allocator<void> A1;
     {
@@ -44,4 +44,6 @@ int main()
         assert(a.resource() == a2.resource());
         assert(a2.resource() == (ex::memory_resource*)42);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.ctor/default.pass.cpp b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.ctor/default.pass.cpp
index acec1a02def0475096bc482dc5accdc367da8150..6a60021e543dacc703a894fefebb0cd51fbe5fc9 100644
--- a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.ctor/default.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.ctor/default.pass.cpp
@@ -23,7 +23,7 @@
 
 namespace ex = std::experimental::pmr;
 
-int main()
+int main(int, char**)
 {
     {
         static_assert(
@@ -45,4 +45,6 @@ int main()
         assert(a.resource() == &R1);
         assert(a2.resource() == ex::new_delete_resource());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.ctor/memory_resource_convert.pass.cpp b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.ctor/memory_resource_convert.pass.cpp
index 0e963117d66d2f4752bd07cb6a3f8e4f1fef15d0..77748ea122a2c3e0291c4bd72c985d8afe183c02 100644
--- a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.ctor/memory_resource_convert.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.ctor/memory_resource_convert.pass.cpp
@@ -22,7 +22,7 @@
 
 namespace ex = std::experimental::pmr;
 
-int main()
+int main(int, char**)
 {
     {
         typedef ex::polymorphic_allocator<void> A;
@@ -41,4 +41,6 @@ int main()
         A const a(&R);
         assert(a.resource() == &R);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.ctor/other_alloc.pass.cpp b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.ctor/other_alloc.pass.cpp
index c0a685615ca008365624acbe9232f4707e739336..21a56f67b5f9eb65d6b57d7a3c37159e5dfa706b 100644
--- a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.ctor/other_alloc.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.ctor/other_alloc.pass.cpp
@@ -22,7 +22,7 @@
 
 namespace ex = std::experimental::pmr;
 
-int main()
+int main(int, char**)
 {
     typedef ex::polymorphic_allocator<void> A1;
     typedef ex::polymorphic_allocator<char> A2;
@@ -53,4 +53,6 @@ int main()
         assert(a.resource() == a2.resource());
         assert(a2.resource() == (ex::memory_resource*)42);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.eq/equal.pass.cpp b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.eq/equal.pass.cpp
index 84672d3b3404e081950de50e5697c8fafd2116f5..6877885a72d6487228a0eeafcd9a0393bd79d839 100644
--- a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.eq/equal.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.eq/equal.pass.cpp
@@ -26,7 +26,7 @@
 
 namespace ex = std::experimental::pmr;
 
-int main()
+int main(int, char**)
 {
     typedef ex::polymorphic_allocator<void> A1;
     typedef ex::polymorphic_allocator<int> A2;
@@ -130,4 +130,6 @@ int main()
         assert(d1.checkIsEqualCalledEq(0));
         assert(d2.checkIsEqualCalledEq(1));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.eq/not_equal.pass.cpp b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.eq/not_equal.pass.cpp
index 7ce6ec1fc5e08438f8dd00b9450c13974e0cb107..39bc3e28ffd33408825538824eb3c211418285a6 100644
--- a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.eq/not_equal.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.eq/not_equal.pass.cpp
@@ -26,7 +26,7 @@
 
 namespace ex = std::experimental::pmr;
 
-int main()
+int main(int, char**)
 {
     typedef ex::polymorphic_allocator<void> A1;
     typedef ex::polymorphic_allocator<int> A2;
@@ -101,4 +101,6 @@ int main()
         assert(d1.checkIsEqualCalledEq(0));
         assert(d2.checkIsEqualCalledEq(1));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/allocate.pass.cpp b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/allocate.pass.cpp
index a489e865c67a809d62fb85cf927488b19622bb47..ce9c82fb4b556dd3317971c7fd2ed48ee32bbf12 100644
--- a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/allocate.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/allocate.pass.cpp
@@ -80,7 +80,7 @@ void testAllocForSizeThrows() {
 }
 #endif // TEST_HAS_NO_EXCEPTIONS
 
-int main()
+int main(int, char**)
 {
     {
         ex::polymorphic_allocator<int> a;
@@ -108,4 +108,6 @@ int main()
         testAllocForSizeThrows<13>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_pair.pass.cpp b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_pair.pass.cpp
index 66a072fb2db8653fcd45fd67b16b49b8c4900704..739d95126f8693d43c5fb90abf4699a48d3a5cf7 100644
--- a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_pair.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_pair.pass.cpp
@@ -34,7 +34,7 @@ struct default_constructible
     int x{0};
 };
 
-int main()
+int main(int, char**)
 {
     // pair<default_constructible, default_constructible> as T()
     {
@@ -49,4 +49,6 @@ int main()
         assert(ptr->second.x == 42);
         std::free(ptr);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_pair_const_lvalue_pair.pass.cpp b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_pair_const_lvalue_pair.pass.cpp
index 16309d6626af18783ef3755b0715d071649e2911..862657a31db7c1381b67b75dd85afcff1f076c97 100644
--- a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_pair_const_lvalue_pair.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_pair_const_lvalue_pair.pass.cpp
@@ -118,7 +118,7 @@ void test_pmr_not_uses_allocator(std::pair<TT, UU> const& p)
 template <class Tp>
 struct Print;
 
-int main()
+int main(int, char**)
 {
     using ERT = std::experimental::erased_type;
     using PMR = ex::memory_resource*;
@@ -139,4 +139,6 @@ int main()
         test_pmr_not_uses_allocator<PMR>(p);
         test_pmr_uses_allocator<PMA>(p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_pair_rvalue.pass.cpp b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_pair_rvalue.pass.cpp
index 91e96cf398263eac20de09520cd8eb1f51a89696..479587ed0d9121da08c7e2810905716bc2047d55 100644
--- a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_pair_rvalue.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_pair_rvalue.pass.cpp
@@ -114,7 +114,7 @@ void test_pmr_not_uses_allocator(std::pair<TT, UU>&& p)
     }
 }
 
-int main()
+int main(int, char**)
 {
     using ERT = std::experimental::erased_type;
     using PMR = ex::memory_resource*;
@@ -135,4 +135,6 @@ int main()
         test_pmr_not_uses_allocator<PMR>(std::move(p));
         test_pmr_uses_allocator<PMA>(std::move(p));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_pair_values.pass.cpp b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_pair_values.pass.cpp
index d6fa37b8480d8661a7628dafc6d0e336a84e701e..9f558581a9cdf40289dc3849cc4f2a736af338e9 100644
--- a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_pair_values.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_pair_values.pass.cpp
@@ -121,7 +121,7 @@ void test_pmr_not_uses_allocator(TT&& t, UU&& u)
     }
 }
 
-int main()
+int main(int, char**)
 {
     using ERT = std::experimental::erased_type;
     using PMR = ex::memory_resource*;
@@ -140,4 +140,6 @@ int main()
         test_pmr_not_uses_allocator<PMR>(std::move(x), y);
         test_pmr_uses_allocator<PMA>(std::move(x), y);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_piecewise_pair.pass.cpp b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_piecewise_pair.pass.cpp
index f043c301e01d515e9f8d5dd0b896abe5284cc2d1..91f315468921916d1c1fe3dbfb6b9cd90eb4dfc8 100644
--- a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_piecewise_pair.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_piecewise_pair.pass.cpp
@@ -111,7 +111,7 @@ void test_pmr_not_uses_allocator(std::tuple<TTypes...> ttuple, std::tuple<UTypes
     }
 }
 
-int main()
+int main(int, char**)
 {
     using ERT = std::experimental::erased_type;
     using PMR = ex::memory_resource*;
@@ -159,4 +159,6 @@ int main()
         test_pmr_uses_allocator<PMA>(           t1, std::move(t2));
         test_pmr_uses_allocator<PMA>(std::move(t2),            t1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_piecewise_pair_evil.pass.cpp b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_piecewise_pair_evil.pass.cpp
index dc19ae170fb5fdd893829e6e955392dd529a8d43..4f30d13c8f4480327fff7bc7d2dd6c825273726d 100644
--- a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_piecewise_pair_evil.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_piecewise_pair_evil.pass.cpp
@@ -120,7 +120,7 @@ void test_evil()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test_evil<WidgetV0, WidgetV0>();
     test_evil<WidgetV0, WidgetV1>();
@@ -138,4 +138,6 @@ int main()
     test_evil<WidgetV3, WidgetV1>();
     test_evil<WidgetV3, WidgetV2>();
     test_evil<WidgetV3, WidgetV3>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_types.pass.cpp b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_types.pass.cpp
index adfe683e23faec2cb6bbdfdf814b9803772d1b7e..526988199ccb9fb88733a139b17aefac2a5b1696 100644
--- a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_types.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/construct_types.pass.cpp
@@ -187,7 +187,7 @@ void test_non_pmr_uses_alloc(AllocObj const& A, Args&&... args)
     }
 }
 
-int main()
+int main(int, char**)
 {
     using ET = std::experimental::erased_type;
     using PMR = ex::memory_resource*;
@@ -223,4 +223,6 @@ int main()
         test_non_pmr_uses_alloc<STDA>(std_alloc, cvalue, std::move(value));
         test_non_pmr_uses_alloc<TESTA>(test_alloc, cvalue, std::move(value));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/deallocate.pass.cpp b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/deallocate.pass.cpp
index 8dadb1773daa1b094500ddb793b29b7ff53b4b14..022478da75df3fa780abf109e20761647ebcf49b 100644
--- a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/deallocate.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/deallocate.pass.cpp
@@ -41,7 +41,7 @@ void testForSizeAndAlign() {
     }
 }
 
-int main()
+int main(int, char**)
 {
     {
         ex::polymorphic_allocator<int> a;
@@ -58,4 +58,6 @@ int main()
         testForSizeAndAlign<73, MA>();
         testForSizeAndAlign<13, MA>();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/destroy.pass.cpp b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/destroy.pass.cpp
index 75c04c53c9113032607ba809224f6e52bf21343e..0a1b60dc2fe0d562ebb9e6ecf60bcccb729643e4 100644
--- a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/destroy.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/destroy.pass.cpp
@@ -32,7 +32,7 @@ struct destroyable
     ~destroyable() { --count; }
 };
 
-int main()
+int main(int, char**)
 {
     typedef ex::polymorphic_allocator<double> A;
     {
@@ -48,4 +48,6 @@ int main()
         assert(count == 0);
         std::free(ptr);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/resource.pass.cpp b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/resource.pass.cpp
index 11d392f5939d33cda27e2431bac0bf11777fbfe3..b05f2b292cace8c4ac46f6fb16f72452e459d270 100644
--- a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/resource.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/resource.pass.cpp
@@ -22,7 +22,7 @@
 
 namespace ex = std::experimental::pmr;
 
-int main()
+int main(int, char**)
 {
     typedef ex::polymorphic_allocator<void> A;
     {
@@ -53,4 +53,6 @@ int main()
         assert(a.resource() == mptr);
         assert(a.resource() == ex::get_default_resource());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/select_on_container_copy_construction.pass.cpp b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/select_on_container_copy_construction.pass.cpp
index 7c7c07d5250dcf9a877a839dfde25dace4d4861a..92beab473ab2952016f7bb3e081b081749d03b9c 100644
--- a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/select_on_container_copy_construction.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.mem/select_on_container_copy_construction.pass.cpp
@@ -22,7 +22,7 @@
 
 namespace ex = std::experimental::pmr;
 
-int main()
+int main(int, char**)
 {
     typedef ex::polymorphic_allocator<void> A;
     {
@@ -49,4 +49,6 @@ int main()
         assert(other.resource() == mptr);
         assert(a.resource() == nullptr);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.overview/nothing_to_do.pass.cpp b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.overview/nothing_to_do.pass.cpp
index 98c4bdd4f1c1fc34ee22a17b22fb2c44aa7f6f21..796f3c353ba17d4aade1333ee2c86b7b85b4bbd7 100644
--- a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.overview/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/memory.polymorphic.allocator.overview/nothing_to_do.pass.cpp
@@ -6,4 +6,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main () {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/nothing_to_do.pass.cpp b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/nothing_to_do.pass.cpp
index 98c4bdd4f1c1fc34ee22a17b22fb2c44aa7f6f21..796f3c353ba17d4aade1333ee2c86b7b85b4bbd7 100644
--- a/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.polymorphic.allocator.class/nothing_to_do.pass.cpp
@@ -6,4 +6,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main () {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/std/experimental/memory/memory.resource.adaptor/memory.resource.adaptor.ctor/alloc_copy.pass.cpp b/libcxx/test/std/experimental/memory/memory.resource.adaptor/memory.resource.adaptor.ctor/alloc_copy.pass.cpp
index 09249219f40f3db5b1ce15cc98bd7c08adac5208..4466b2b4e5155c0f905201aa82bfadc165edcd46 100644
--- a/libcxx/test/std/experimental/memory/memory.resource.adaptor/memory.resource.adaptor.ctor/alloc_copy.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource.adaptor/memory.resource.adaptor.ctor/alloc_copy.pass.cpp
@@ -21,7 +21,7 @@
 
 namespace ex = std::experimental::pmr;
 
-int main()
+int main(int, char**)
 {
     typedef CountingAllocator<char> AllocT;
     typedef ex::resource_adaptor<AllocT> R;
@@ -49,4 +49,6 @@ int main()
         assert(P.move_constructed == 0);
         assert(r.get_allocator() == a);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.resource.adaptor/memory.resource.adaptor.ctor/alloc_move.pass.cpp b/libcxx/test/std/experimental/memory/memory.resource.adaptor/memory.resource.adaptor.ctor/alloc_move.pass.cpp
index df54ba503aa156096d57b051b072f22f5da3f26f..b6af8515100cb2466ac20eee606f021c8efc166f 100644
--- a/libcxx/test/std/experimental/memory/memory.resource.adaptor/memory.resource.adaptor.ctor/alloc_move.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource.adaptor/memory.resource.adaptor.ctor/alloc_move.pass.cpp
@@ -21,7 +21,7 @@
 
 namespace ex = std::experimental::pmr;
 
-int main()
+int main(int, char**)
 {
     typedef CountingAllocator<char> AllocT;
     typedef ex::resource_adaptor<AllocT> R;
@@ -40,4 +40,6 @@ int main()
         assert(P.move_constructed == 1);
         assert(r.get_allocator() == AllocT{P});
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.resource.adaptor/memory.resource.adaptor.ctor/default.pass.cpp b/libcxx/test/std/experimental/memory/memory.resource.adaptor/memory.resource.adaptor.ctor/default.pass.cpp
index 5550e4fa519a1132fc70a24eea82519f32f7e1ae..53481ab39f215fecbd09a0fd532770a010320240 100644
--- a/libcxx/test/std/experimental/memory/memory.resource.adaptor/memory.resource.adaptor.ctor/default.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource.adaptor/memory.resource.adaptor.ctor/default.pass.cpp
@@ -23,7 +23,7 @@
 
 namespace ex = std::experimental::pmr;
 
-int main()
+int main(int, char**)
 {
     {
         typedef CountingAllocator<char> AllocT; // Not default constructible
@@ -36,4 +36,6 @@ int main()
         static_assert(std::is_default_constructible<R>::value, "");
         R r; ((void)r);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.resource.adaptor/memory.resource.adaptor.mem/do_allocate_and_deallocate.pass.cpp b/libcxx/test/std/experimental/memory/memory.resource.adaptor/memory.resource.adaptor.mem/do_allocate_and_deallocate.pass.cpp
index b2dc3aae18c33987f9f418ef1495e70ea123c782..806fa6e95e15bf0485641e8b50d481a6f50bbd48 100644
--- a/libcxx/test/std/experimental/memory/memory.resource.adaptor/memory.resource.adaptor.mem/do_allocate_and_deallocate.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource.adaptor/memory.resource.adaptor.mem/do_allocate_and_deallocate.pass.cpp
@@ -106,9 +106,11 @@ void check_alloc_max_size() {
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     check_allocate_deallocate<CountingAllocator<char>>();
     check_allocate_deallocate<MinAlignedAllocator<char>>();
     check_alloc_max_size();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.resource.adaptor/memory.resource.adaptor.mem/do_is_equal.pass.cpp b/libcxx/test/std/experimental/memory/memory.resource.adaptor/memory.resource.adaptor.mem/do_is_equal.pass.cpp
index baa8e17c52f0875519d2ad69b94917fc9e8f9a96..71c36693c3c774a4cb63303aae35e87e78cb82b7 100644
--- a/libcxx/test/std/experimental/memory/memory.resource.adaptor/memory.resource.adaptor.mem/do_is_equal.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource.adaptor/memory.resource.adaptor.mem/do_is_equal.pass.cpp
@@ -23,7 +23,7 @@
 using std::size_t;
 namespace ex = std::experimental::pmr;
 
-int main()
+int main(int, char**)
 {
 
     typedef CountingAllocator<char> Alloc1;
@@ -79,4 +79,6 @@ int main()
         assert(!m1.is_equal(m2));
         assert(!m2.is_equal(m1));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.resource.adaptor/memory.resource.adaptor.overview/overview.pass.cpp b/libcxx/test/std/experimental/memory/memory.resource.adaptor/memory.resource.adaptor.overview/overview.pass.cpp
index a47968e905a89613691ca4a28f3d21e67382c9ee..873dfd9391cc886b72f628469cb93406cd05bc83 100644
--- a/libcxx/test/std/experimental/memory/memory.resource.adaptor/memory.resource.adaptor.overview/overview.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource.adaptor/memory.resource.adaptor.overview/overview.pass.cpp
@@ -19,7 +19,7 @@
 
 namespace ex = std::experimental::pmr;
 
-int main()
+int main(int, char**)
 {
     typedef ex::resource_adaptor<std::allocator<void>> R;
     typedef ex::resource_adaptor<std::allocator<long>> R2;
@@ -35,4 +35,6 @@ int main()
         static_assert(std::is_copy_assignable<R>::value, "");
         static_assert(std::is_move_assignable<R>::value, "");
    }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.resource.aliases/header_deque_synop.pass.cpp b/libcxx/test/std/experimental/memory/memory.resource.aliases/header_deque_synop.pass.cpp
index 80e3c6e2e5dc8a75330bb4311c0a913073db9253..2aba4431e63083420def83236abedbd37607d3ff 100644
--- a/libcxx/test/std/experimental/memory/memory.resource.aliases/header_deque_synop.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource.aliases/header_deque_synop.pass.cpp
@@ -26,11 +26,13 @@
 
 namespace pmr = std::experimental::pmr;
 
-int main()
+int main(int, char**)
 {
     using StdDeque = std::deque<int, pmr::polymorphic_allocator<int>>;
     using PmrDeque = pmr::deque<int>;
     static_assert(std::is_same<StdDeque, PmrDeque>::value, "");
     PmrDeque d;
     assert(d.get_allocator().resource() == pmr::get_default_resource());
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.resource.aliases/header_forward_list_synop.pass.cpp b/libcxx/test/std/experimental/memory/memory.resource.aliases/header_forward_list_synop.pass.cpp
index 5fc71fb9a1801d64b87b2eb2e80ff9c888777b03..66adb0b511dad6e08c00a56f3e318e2e01c6c34c 100644
--- a/libcxx/test/std/experimental/memory/memory.resource.aliases/header_forward_list_synop.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource.aliases/header_forward_list_synop.pass.cpp
@@ -26,11 +26,13 @@
 
 namespace pmr = std::experimental::pmr;
 
-int main()
+int main(int, char**)
 {
     using StdForwardList = std::forward_list<int, pmr::polymorphic_allocator<int>>;
     using PmrForwardList = pmr::forward_list<int>;
     static_assert(std::is_same<StdForwardList, PmrForwardList>::value, "");
     PmrForwardList d;
     assert(d.get_allocator().resource() == pmr::get_default_resource());
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.resource.aliases/header_list_synop.pass.cpp b/libcxx/test/std/experimental/memory/memory.resource.aliases/header_list_synop.pass.cpp
index 3a13f13038980767076b99573a0a119c68c94818..2884a3fbb7449eb53ec39152786c7f47f8a8820d 100644
--- a/libcxx/test/std/experimental/memory/memory.resource.aliases/header_list_synop.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource.aliases/header_list_synop.pass.cpp
@@ -26,11 +26,13 @@
 
 namespace pmr = std::experimental::pmr;
 
-int main()
+int main(int, char**)
 {
     using StdList = std::list<int, pmr::polymorphic_allocator<int>>;
     using PmrList = pmr::list<int>;
     static_assert(std::is_same<StdList, PmrList>::value, "");
     PmrList d;
     assert(d.get_allocator().resource() == pmr::get_default_resource());
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.resource.aliases/header_map_synop.pass.cpp b/libcxx/test/std/experimental/memory/memory.resource.aliases/header_map_synop.pass.cpp
index 507aaf7b7bc9ad95b2df798c6eb7cac718f6d347..5b221c539ee084d54d0afbdbc50f78dd5c124092 100644
--- a/libcxx/test/std/experimental/memory/memory.resource.aliases/header_map_synop.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource.aliases/header_map_synop.pass.cpp
@@ -30,7 +30,7 @@
 
 namespace pmr = std::experimental::pmr;
 
-int main()
+int main(int, char**)
 {
     using K = int;
     using V = char;
@@ -65,4 +65,6 @@ int main()
         pmr::multimap<int, int> m;
         assert(m.get_allocator().resource() == pmr::get_default_resource());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.resource.aliases/header_regex_synop.pass.cpp b/libcxx/test/std/experimental/memory/memory.resource.aliases/header_regex_synop.pass.cpp
index ffc6f4239d53dd1ad343abdea0dc4fe04b4087e7..95f6d6f0c1e9f3f85383dcfea93a4e296ead9f38 100644
--- a/libcxx/test/std/experimental/memory/memory.resource.aliases/header_regex_synop.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource.aliases/header_regex_synop.pass.cpp
@@ -40,7 +40,7 @@ void test_match_result_typedef() {
     static_assert(std::is_same<PmrMR, PmrTypedef>::value, "");
 }
 
-int main()
+int main(int, char**)
 {
     {
         test_match_result_typedef<const char*, pmr::cmatch>();
@@ -53,4 +53,6 @@ int main()
         pmr::smatch s;
         assert(s.get_allocator().resource() == pmr::get_default_resource());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.resource.aliases/header_set_synop.pass.cpp b/libcxx/test/std/experimental/memory/memory.resource.aliases/header_set_synop.pass.cpp
index 42b6f33ebce114fe7940295de110fe441e53a29e..4ee12d61a0db85b0c3e4c8d6bb9476d2f4a4496a 100644
--- a/libcxx/test/std/experimental/memory/memory.resource.aliases/header_set_synop.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource.aliases/header_set_synop.pass.cpp
@@ -30,7 +30,7 @@
 
 namespace pmr = std::experimental::pmr;
 
-int main()
+int main(int, char**)
 {
     using V = char;
     using DC = std::less<V>;
@@ -63,4 +63,6 @@ int main()
         pmr::multiset<int> m;
         assert(m.get_allocator().resource() == pmr::get_default_resource());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.resource.aliases/header_string_synop.pass.cpp b/libcxx/test/std/experimental/memory/memory.resource.aliases/header_string_synop.pass.cpp
index 081466dbc7714ce8a185b197f2399af81b6802b4..3a730fafea1efeb10d7712cd512fbbe6c9649e74 100644
--- a/libcxx/test/std/experimental/memory/memory.resource.aliases/header_string_synop.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource.aliases/header_string_synop.pass.cpp
@@ -50,7 +50,7 @@ void test_basic_string_alias() {
     static_assert(std::is_same<StdStr, PmrStr>::value, "");
 }
 
-int main()
+int main(int, char**)
 {
     {
         test_string_typedef<char,     pmr::string>();
@@ -69,4 +69,6 @@ int main()
         pmr::string s;
         assert(s.get_allocator().resource() == pmr::get_default_resource());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.resource.aliases/header_unordered_map_synop.pass.cpp b/libcxx/test/std/experimental/memory/memory.resource.aliases/header_unordered_map_synop.pass.cpp
index 190cfd40fecde8cc7b1ac04d86be3aaef85c1e37..8b07d68a016df70b4e14c24ef08edd14a69ea475 100644
--- a/libcxx/test/std/experimental/memory/memory.resource.aliases/header_unordered_map_synop.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource.aliases/header_unordered_map_synop.pass.cpp
@@ -36,7 +36,7 @@ struct MyHash : std::hash<T> {};
 template <class T>
 struct MyPred : std::equal_to<T> {};
 
-int main()
+int main(int, char**)
 {
     using K = int;
     using V = char;
@@ -83,4 +83,6 @@ int main()
         pmr::unordered_multimap<int, int> m;
         assert(m.get_allocator().resource() == pmr::get_default_resource());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.resource.aliases/header_unordered_set_synop.pass.cpp b/libcxx/test/std/experimental/memory/memory.resource.aliases/header_unordered_set_synop.pass.cpp
index 7a795d08fae8e148b3ccc22aeeea1351e227f66f..c4238dee184b2ed66c1d65f9eaf48977945d4d13 100644
--- a/libcxx/test/std/experimental/memory/memory.resource.aliases/header_unordered_set_synop.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource.aliases/header_unordered_set_synop.pass.cpp
@@ -36,7 +36,7 @@ struct MyHash : std::hash<T> {};
 template <class T>
 struct MyPred : std::equal_to<T> {};
 
-int main()
+int main(int, char**)
 {
     using V = char;
     using DH = std::hash<V>;
@@ -81,4 +81,6 @@ int main()
         pmr::unordered_multiset<int> m;
         assert(m.get_allocator().resource() == pmr::get_default_resource());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.resource.aliases/header_vector_synop.pass.cpp b/libcxx/test/std/experimental/memory/memory.resource.aliases/header_vector_synop.pass.cpp
index ea8d11e1473043c164035c987df77648ee959372..a5c0e8bbd3c53cacfc0aeab24d55a65687eae2c3 100644
--- a/libcxx/test/std/experimental/memory/memory.resource.aliases/header_vector_synop.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource.aliases/header_vector_synop.pass.cpp
@@ -26,11 +26,13 @@
 
 namespace pmr = std::experimental::pmr;
 
-int main()
+int main(int, char**)
 {
     using StdVector = std::vector<int, pmr::polymorphic_allocator<int>>;
     using PmrVector = pmr::vector<int>;
     static_assert(std::is_same<StdVector, PmrVector>::value, "");
     PmrVector d;
     assert(d.get_allocator().resource() == pmr::get_default_resource());
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.resource.global/default_resource.pass.cpp b/libcxx/test/std/experimental/memory/memory.resource.global/default_resource.pass.cpp
index 91a9027a2cc3658f31606c2535249235dcbe7696..c3bf1a2fcfd43008dc55917ae31d343f2a3d9c43 100644
--- a/libcxx/test/std/experimental/memory/memory.resource.global/default_resource.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource.global/default_resource.pass.cpp
@@ -36,7 +36,7 @@
 
 using namespace std::experimental::pmr;
 
-int main() {
+int main(int, char**) {
     TestResource R;
     { // Test (A) and (B)
         memory_resource* p = get_default_resource();
@@ -70,4 +70,6 @@ int main() {
         static_assert(noexcept(set_default_resource(nullptr)),
                       "set_default_resource() must be noexcept");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.resource.global/new_delete_resource.pass.cpp b/libcxx/test/std/experimental/memory/memory.resource.global/new_delete_resource.pass.cpp
index 958490d78c6136a9e061946908a161a1cfd0573e..da340d7a000120631fef7b8a139298b59b4abae1 100644
--- a/libcxx/test/std/experimental/memory/memory.resource.global/new_delete_resource.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource.global/new_delete_resource.pass.cpp
@@ -92,10 +92,12 @@ void test_allocate_deallocate()
 
 }
 
-int main()
+int main(int, char**)
 {
     static_assert(noexcept(ex::new_delete_resource()), "Must be noexcept");
     test_return();
     test_equality();
     test_allocate_deallocate();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.resource.global/null_memory_resource.pass.cpp b/libcxx/test/std/experimental/memory/memory.resource.global/null_memory_resource.pass.cpp
index aab29728f8f6753132d9b96c4316f4d4b81c1f00..f7111b49325a46288452058ac99c335fca68437a 100644
--- a/libcxx/test/std/experimental/memory/memory.resource.global/null_memory_resource.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource.global/null_memory_resource.pass.cpp
@@ -108,10 +108,12 @@ void test_deallocate()
     assert(globalMemCounter.checkDeleteArrayCalledEq(0));
 }
 
-int main()
+int main(int, char**)
 {
     test_return();
     test_equality();
     test_allocate();
     test_deallocate();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.resource.synop/nothing_to_do.pass.cpp b/libcxx/test/std/experimental/memory/memory.resource.synop/nothing_to_do.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/std/experimental/memory/memory.resource.synop/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource.synop/nothing_to_do.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.resource/construct.fail.cpp b/libcxx/test/std/experimental/memory/memory.resource/construct.fail.cpp
index d23f583505e469f47399b21114bdeb8c8817dedd..f4d57be8dc67aafaef94ba80cd3112e556b48680 100644
--- a/libcxx/test/std/experimental/memory/memory.resource/construct.fail.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource/construct.fail.cpp
@@ -18,7 +18,9 @@
 
 namespace ex = std::experimental::pmr;
 
-int main()
+int main(int, char**)
 {
     ex::memory_resource m; // expected-error {{variable type 'ex::memory_resource' is an abstract class}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.resource/memory.resource.eq/equal.pass.cpp b/libcxx/test/std/experimental/memory/memory.resource/memory.resource.eq/equal.pass.cpp
index 774e6c7e76cf17b98bb1a28b5b172966a8972bbb..f9d4d5beb91f1edc44ec7276c39bb0c6e7653d4f 100644
--- a/libcxx/test/std/experimental/memory/memory.resource/memory.resource.eq/equal.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource/memory.resource.eq/equal.pass.cpp
@@ -21,7 +21,7 @@
 
 namespace ex = std::experimental::pmr;
 
-int main()
+int main(int, char**)
 {
     // check return types
     {
@@ -72,4 +72,6 @@ int main()
         assert(r1.checkIsEqualCalledEq(1));
         assert(r2.checkIsEqualCalledEq(1));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.resource/memory.resource.eq/not_equal.pass.cpp b/libcxx/test/std/experimental/memory/memory.resource/memory.resource.eq/not_equal.pass.cpp
index c9ce391381825f390f44ef654712e45353972424..037bb1a9613777a9afc9a60f5c1490da4ca12fa7 100644
--- a/libcxx/test/std/experimental/memory/memory.resource/memory.resource.eq/not_equal.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource/memory.resource.eq/not_equal.pass.cpp
@@ -20,7 +20,7 @@
 
 namespace ex = std::experimental::pmr;
 
-int main()
+int main(int, char**)
 {
     // check return types
     {
@@ -71,4 +71,6 @@ int main()
         assert(!(mr2 != mr1));
         assert(r1.checkIsEqualCalledEq(0));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.resource/memory.resource.overview/nothing_to_do.pass.cpp b/libcxx/test/std/experimental/memory/memory.resource/memory.resource.overview/nothing_to_do.pass.cpp
index 98c4bdd4f1c1fc34ee22a17b22fb2c44aa7f6f21..796f3c353ba17d4aade1333ee2c86b7b85b4bbd7 100644
--- a/libcxx/test/std/experimental/memory/memory.resource/memory.resource.overview/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource/memory.resource.overview/nothing_to_do.pass.cpp
@@ -6,4 +6,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main () {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/std/experimental/memory/memory.resource/memory.resource.priv/protected_members.fail.cpp b/libcxx/test/std/experimental/memory/memory.resource/memory.resource.priv/protected_members.fail.cpp
index 15db1b365b45c3ee976063d69bb35b7894bcdd77..faa3a252e843ddecfbf2ffd00601979ce21ca3ca 100644
--- a/libcxx/test/std/experimental/memory/memory.resource/memory.resource.priv/protected_members.fail.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource/memory.resource.priv/protected_members.fail.cpp
@@ -18,9 +18,11 @@
 
 namespace ex = std::experimental::pmr;
 
-int main() {
+int main(int, char**) {
     ex::memory_resource *m = ex::new_delete_resource();
     m->do_allocate(0, 0); // expected-error{{'do_allocate' is a protected member}}
     m->do_deallocate(nullptr, 0, 0); // expected-error{{'do_deallocate' is a protected member}}
     m->do_is_equal(*m); // expected-error{{'do_is_equal' is a protected member}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.resource/memory.resource.public/allocate.pass.cpp b/libcxx/test/std/experimental/memory/memory.resource/memory.resource.public/allocate.pass.cpp
index 77aa1da3c830599e7f92575b4e7c4baf83b856cf..38f49743cca7b307461795d5402f7602937db482 100644
--- a/libcxx/test/std/experimental/memory/memory.resource/memory.resource.public/allocate.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource/memory.resource.public/allocate.pass.cpp
@@ -31,7 +31,7 @@
 
 using std::experimental::pmr::memory_resource;
 
-int main()
+int main(int, char**)
 {
     TestResource R(42);
     auto& P = R.getController();
@@ -85,4 +85,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.resource/memory.resource.public/deallocate.pass.cpp b/libcxx/test/std/experimental/memory/memory.resource/memory.resource.public/deallocate.pass.cpp
index c76036811b3d350513bfe0b29698c8b3d23cd72c..e8c2d5bfff151ed3d93f2a48a01c8ae97b2dd111 100644
--- a/libcxx/test/std/experimental/memory/memory.resource/memory.resource.public/deallocate.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource/memory.resource.public/deallocate.pass.cpp
@@ -30,7 +30,7 @@
 
 using std::experimental::pmr::memory_resource;
 
-int main()
+int main(int, char**)
 {
     NullResource R(42);
     auto& P = R.getController();
@@ -70,4 +70,6 @@ int main()
         assert(P.dealloc_count == 2);
         assert(P.checkDealloc(p, s, a));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.resource/memory.resource.public/dtor.pass.cpp b/libcxx/test/std/experimental/memory/memory.resource/memory.resource.public/dtor.pass.cpp
index db9156834fe3f4fc06c8712e834597e6bf2c3211..be5ea2fb008e6f7a2c7b6b1981391d8555e573a1 100644
--- a/libcxx/test/std/experimental/memory/memory.resource/memory.resource.public/dtor.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource/memory.resource.public/dtor.pass.cpp
@@ -26,7 +26,7 @@
 
 using std::experimental::pmr::memory_resource;
 
-int main()
+int main(int, char**)
 {
     static_assert(
         std::has_virtual_destructor<memory_resource>::value
@@ -55,4 +55,6 @@ int main()
         assert(TR::resource_constructed == 1);
         assert(TR::resource_destructed == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/memory.resource/memory.resource.public/is_equal.pass.cpp b/libcxx/test/std/experimental/memory/memory.resource/memory.resource.public/is_equal.pass.cpp
index e2ff9d9d12255ce0d61ddf4497a2dd8bc87cf6a9..f0e517870852a0c14c1ac81fbc53c050cf64d1a0 100644
--- a/libcxx/test/std/experimental/memory/memory.resource/memory.resource.public/is_equal.pass.cpp
+++ b/libcxx/test/std/experimental/memory/memory.resource/memory.resource.public/is_equal.pass.cpp
@@ -28,7 +28,7 @@
 
 using std::experimental::pmr::memory_resource;
 
-int main()
+int main(int, char**)
 {
     {
         memory_resource const* r1 = nullptr;
@@ -89,4 +89,6 @@ int main()
         assert(P2.checkIsEqualCalledEq(1));
         assert(P1.checkIsEqualCalledEq(1));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/memory/nothing_to_do.pass.cpp b/libcxx/test/std/experimental/memory/nothing_to_do.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/std/experimental/memory/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/experimental/memory/nothing_to_do.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/nothing_to_do.pass.cpp b/libcxx/test/std/experimental/nothing_to_do.pass.cpp
index 98c4bdd4f1c1fc34ee22a17b22fb2c44aa7f6f21..796f3c353ba17d4aade1333ee2c86b7b85b4bbd7 100644
--- a/libcxx/test/std/experimental/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/experimental/nothing_to_do.pass.cpp
@@ -6,4 +6,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main () {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/std/experimental/simd/simd.abi/vector_extension.pass.cpp b/libcxx/test/std/experimental/simd/simd.abi/vector_extension.pass.cpp
index a17e96df6a0d06f869aecd54a4ee4246d970fa37..6bd56d2dda7d4be919577bef0ac569eafc7b5ca1 100644
--- a/libcxx/test/std/experimental/simd/simd.abi/vector_extension.pass.cpp
+++ b/libcxx/test/std/experimental/simd/simd.abi/vector_extension.pass.cpp
@@ -63,4 +63,6 @@ static_assert(std::is_same<ex::simd_abi::compatible<int8_t>,
                            ex::__simd_abi<ex::_StorageKind::_Array, 16>>::value,
               "");
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/std/experimental/simd/simd.access/default.pass.cpp b/libcxx/test/std/experimental/simd/simd.access/default.pass.cpp
index 9b179f2c79d66fe337dc968171837fd549f59893..6e6e4fe9e9a2ae65fb2823bcf21f9c3dcd63d444 100644
--- a/libcxx/test/std/experimental/simd/simd.access/default.pass.cpp
+++ b/libcxx/test/std/experimental/simd/simd.access/default.pass.cpp
@@ -210,7 +210,9 @@ void test_access() {
   }
 }
 
-int main() {
+int main(int, char**) {
   test_access<ex::native_simd<int>>();
   test_access<ex::fixed_size_simd<int, 4>>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/simd/simd.casts/simd_cast.pass.cpp b/libcxx/test/std/experimental/simd/simd.casts/simd_cast.pass.cpp
index 7f70c5b02bb4cb0b5464fa75d990bf3837914b86..ec4a32bf9d72832867d6a56191387a32b22e577c 100644
--- a/libcxx/test/std/experimental/simd/simd.casts/simd_cast.pass.cpp
+++ b/libcxx/test/std/experimental/simd/simd.casts/simd_cast.pass.cpp
@@ -42,4 +42,6 @@ static_assert(
         ex::simd<int64_t, ex::simd_abi::scalar>>::value,
     "");
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/std/experimental/simd/simd.casts/static_simd_cast.pass.cpp b/libcxx/test/std/experimental/simd/simd.casts/static_simd_cast.pass.cpp
index a01e423583b555750bfcd901a9a0e118b009d499..40922ce1153edb76165b885eb6c53119b9bed779 100644
--- a/libcxx/test/std/experimental/simd/simd.casts/static_simd_cast.pass.cpp
+++ b/libcxx/test/std/experimental/simd/simd.casts/static_simd_cast.pass.cpp
@@ -37,4 +37,6 @@ static_assert(
         ex::simd<float, ex::simd_abi::scalar>>::value,
     "");
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/std/experimental/simd/simd.cons/broadcast.pass.cpp b/libcxx/test/std/experimental/simd/simd.cons/broadcast.pass.cpp
index 2e34bb9acf0935768076af9b3eed05b5f7b15715..25dd8a4c5341067b5f90b91407216e9c2aad98a8 100644
--- a/libcxx/test/std/experimental/simd/simd.cons/broadcast.pass.cpp
+++ b/libcxx/test/std/experimental/simd/simd.cons/broadcast.pass.cpp
@@ -78,8 +78,10 @@ void test_broadcast() {
   }
 }
 
-int main() {
+int main(int, char**) {
   test_broadcast<ex::native_simd<int>>();
   test_broadcast<ex::fixed_size_simd<int, 4>>();
   test_broadcast<ex::fixed_size_simd<int, 15>>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/simd/simd.cons/default.pass.cpp b/libcxx/test/std/experimental/simd/simd.cons/default.pass.cpp
index 2e64a8219648eedad6e9a4089d9d6cb8abb7ad25..6eebe0ec0cf83fb74ebffb8d3fc8aef25e2fa7eb 100644
--- a/libcxx/test/std/experimental/simd/simd.cons/default.pass.cpp
+++ b/libcxx/test/std/experimental/simd/simd.cons/default.pass.cpp
@@ -18,10 +18,12 @@
 
 namespace ex = std::experimental::parallelism_v2;
 
-int main() {
+int main(int, char**) {
   static_assert(ex::native_simd<int32_t>().size() > 0, "");
   static_assert(ex::fixed_size_simd<int32_t, 4>().size() == 4, "");
   static_assert(ex::fixed_size_simd<int32_t, 5>().size() == 5, "");
   static_assert(ex::fixed_size_simd<int32_t, 1>().size() == 1, "");
   static_assert(ex::fixed_size_simd<char, 32>().size() == 32, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/simd/simd.cons/generator.pass.cpp b/libcxx/test/std/experimental/simd/simd.cons/generator.pass.cpp
index 542715de66bba8294f9381d931b59774a4bd8001..19880e9d3015d258867af7e7bf8fc2489306a080 100644
--- a/libcxx/test/std/experimental/simd/simd.cons/generator.pass.cpp
+++ b/libcxx/test/std/experimental/simd/simd.cons/generator.pass.cpp
@@ -82,9 +82,11 @@ void test_generator() {
   }
 }
 
-int main() {
+int main(int, char**) {
   // TODO: adjust the tests when this assertion fails.
   assert(ex::native_simd<int32_t>::size() >= 4);
   test_generator<ex::native_simd<int32_t>>();
   test_generator<ex::fixed_size_simd<int32_t, 4>>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/simd/simd.cons/load.pass.cpp b/libcxx/test/std/experimental/simd/simd.cons/load.pass.cpp
index 3056e47fd4ba1897ad26dbf68f01f56bbf3223fa..9440d5aefa358119cb5b5a103821bbcbe9c5386e 100644
--- a/libcxx/test/std/experimental/simd/simd.cons/load.pass.cpp
+++ b/libcxx/test/std/experimental/simd/simd.cons/load.pass.cpp
@@ -107,11 +107,13 @@ void test_converting_load_ctor() {
   assert(a[3] == 8);
 }
 
-int main() {
+int main(int, char**) {
   // TODO: adjust the tests when this assertion fails.
   assert(ex::native_simd<int32_t>::size() >= 4);
   test_load_ctor<ex::native_simd<int32_t>>();
   test_load_ctor<ex::fixed_size_simd<int32_t, 4>>();
   test_converting_load_ctor<ex::native_simd<int32_t>>();
   test_converting_load_ctor<ex::fixed_size_simd<int32_t, 4>>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/simd/simd.mem/load.pass.cpp b/libcxx/test/std/experimental/simd/simd.mem/load.pass.cpp
index 9bda07ee9ea4bf3661a2647a921f31af08ff7a4f..1a56161c5fb0a3eba26e27478e1e0982600a407f 100644
--- a/libcxx/test/std/experimental/simd/simd.mem/load.pass.cpp
+++ b/libcxx/test/std/experimental/simd/simd.mem/load.pass.cpp
@@ -111,11 +111,13 @@ void test_converting_load() {
   assert(a[3] == 8);
 }
 
-int main() {
+int main(int, char**) {
   // TODO: adjust the tests when this assertion fails.
   assert(ex::native_simd<int32_t>::size() >= 4);
   test_load<ex::native_simd<int32_t>>();
   test_load<ex::fixed_size_simd<int32_t, 4>>();
   test_converting_load<ex::native_simd<int32_t>>();
   test_converting_load<ex::fixed_size_simd<int32_t, 4>>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/simd/simd.mem/store.pass.cpp b/libcxx/test/std/experimental/simd/simd.mem/store.pass.cpp
index 3faf400006a05069f2fa609ec4081fe4769f1d08..3cc3d1fa14dc79f4bc26b1da741ed6f50fa5c108 100644
--- a/libcxx/test/std/experimental/simd/simd.mem/store.pass.cpp
+++ b/libcxx/test/std/experimental/simd/simd.mem/store.pass.cpp
@@ -85,10 +85,12 @@ void test_converting_store() {
   assert(buffer[3] == 8.);
 }
 
-int main() {
+int main(int, char**) {
   // TODO: adjust the tests when this assertion fails.
   test_store<ex::native_simd<int32_t>>();
   test_store<ex::fixed_size_simd<int32_t, 4>>();
   test_converting_store<ex::native_simd<int32_t>>();
   test_converting_store<ex::fixed_size_simd<int32_t, 4>>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/simd/simd.traits/abi_for_size.pass.cpp b/libcxx/test/std/experimental/simd/simd.traits/abi_for_size.pass.cpp
index a2206780fc76ae1afcce59f8116793280bc7b6ca..2bf28dc8a211b4b2f832e75260e931b5255f01af 100644
--- a/libcxx/test/std/experimental/simd/simd.traits/abi_for_size.pass.cpp
+++ b/libcxx/test/std/experimental/simd/simd.traits/abi_for_size.pass.cpp
@@ -28,4 +28,6 @@ static_assert(std::is_same<ex::abi_for_size_t<int, 4>,
                            ex::simd_abi::fixed_size<4>>::value,
               "");
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/std/experimental/simd/simd.traits/is_abi_tag.pass.cpp b/libcxx/test/std/experimental/simd/simd.traits/is_abi_tag.pass.cpp
index f07fca8296a3dab03d097dbd592698913d0cf0d8..db98dae2b6799c09ce6c2a4b19a56925022a2644 100644
--- a/libcxx/test/std/experimental/simd/simd.traits/is_abi_tag.pass.cpp
+++ b/libcxx/test/std/experimental/simd/simd.traits/is_abi_tag.pass.cpp
@@ -109,4 +109,6 @@ static_assert(!ex::is_abi_tag_v<ex::simd<float>>, "");
 static_assert(!ex::is_abi_tag_v<ex::simd_mask<int>>, "");
 static_assert(!ex::is_abi_tag_v<ex::simd_mask<float>>, "");
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/std/experimental/simd/simd.traits/is_simd.pass.cpp b/libcxx/test/std/experimental/simd/simd.traits/is_simd.pass.cpp
index 46326ab5fa1d6b5631fdc47a7ccc41596366596e..c465f0de68169d032865dd8c4c3cc34b1890ac9a 100644
--- a/libcxx/test/std/experimental/simd/simd.traits/is_simd.pass.cpp
+++ b/libcxx/test/std/experimental/simd/simd.traits/is_simd.pass.cpp
@@ -125,4 +125,6 @@ static_assert(!ex::is_simd_v<ex::simd_mask<int>>, "");
 static_assert(!ex::is_simd_v<ex::simd_mask<float>>, "");
 static_assert(!ex::is_simd_v<UserType>, "");
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/std/experimental/simd/simd.traits/is_simd_flag_type.pass.cpp b/libcxx/test/std/experimental/simd/simd.traits/is_simd_flag_type.pass.cpp
index d91d906caceb6de150a38ad305908defa1becf37..5fa208a3be775a094fac66f4ed99f88092590b6c 100644
--- a/libcxx/test/std/experimental/simd/simd.traits/is_simd_flag_type.pass.cpp
+++ b/libcxx/test/std/experimental/simd/simd.traits/is_simd_flag_type.pass.cpp
@@ -47,4 +47,6 @@ static_assert(!ex::is_simd_flag_type_v<UserType>, "");
 static_assert(!ex::is_simd_flag_type_v<ex::simd<int8_t>>, "");
 static_assert(!ex::is_simd_flag_type_v<ex::simd_mask<int8_t>>, "");
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/std/experimental/simd/simd.traits/is_simd_mask.pass.cpp b/libcxx/test/std/experimental/simd/simd.traits/is_simd_mask.pass.cpp
index 5346afef5afd43a13f036802d0457c5e3c6e9bec..348f2bfdfc3bdbaf91bae6df5bfd6bf7ddaf5517 100644
--- a/libcxx/test/std/experimental/simd/simd.traits/is_simd_mask.pass.cpp
+++ b/libcxx/test/std/experimental/simd/simd.traits/is_simd_mask.pass.cpp
@@ -148,4 +148,6 @@ static_assert(!ex::is_simd_mask_v<ex::simd<int>>, "");
 static_assert(!ex::is_simd_mask_v<ex::simd<float>>, "");
 static_assert(!ex::is_simd_mask_v<UserType>, "");
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/std/experimental/utilities/meta/meta.detect/detected_or.pass.cpp b/libcxx/test/std/experimental/utilities/meta/meta.detect/detected_or.pass.cpp
index 658bf0c120983170b5b90e6f93d86392f4888638..3ad12b617aeef3f87164edabbb861af2f50677cc 100644
--- a/libcxx/test/std/experimental/utilities/meta/meta.detect/detected_or.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/meta/meta.detect/detected_or.pass.cpp
@@ -33,7 +33,9 @@ void test() {
     static_assert( std::is_same<Res, typename ex::detected_or_t<double, hasFoo, T>      >::value, "" );
 }
 
-int main () {
+int main(int, char**) {
     test<yesFoo, int>();
     test<noFoo, double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/meta/meta.detect/detected_t.pass.cpp b/libcxx/test/std/experimental/utilities/meta/meta.detect/detected_t.pass.cpp
index 7d3304fbcb4dac1171d2463b0e133a8bf7791d41..ebb7ecc7d9c04d0d26eb5e9979e2a3f8936bd1f2 100644
--- a/libcxx/test/std/experimental/utilities/meta/meta.detect/detected_t.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/meta/meta.detect/detected_t.pass.cpp
@@ -40,8 +40,10 @@ void test() {
     static_assert( std::is_same<Res, typename ex::detected_t<callFoo, T>>::value, "" );
 }
 
-int main () {
+int main(int, char**) {
     test<yesFoo, int>();
     test<noFoo, ex::nonesuch>();  // lookup failure returns nonesuch
     test<wrongFoo, std::string>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/meta/meta.detect/is_detected.pass.cpp b/libcxx/test/std/experimental/utilities/meta/meta.detect/is_detected.pass.cpp
index 24c9d7011742c58c8db737143b6055b9995a0627..60b1acae8807cad5183279d3aea93cf7690b80db 100644
--- a/libcxx/test/std/experimental/utilities/meta/meta.detect/is_detected.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/meta/meta.detect/is_detected.pass.cpp
@@ -29,8 +29,10 @@ void test() {
     static_assert( b == ex::is_detected_v<copy_assign_t, T>, "" );
 }
 
-int main () {
+int main(int, char**) {
     test<int, true>();
     test<std::string, true>();
     test<not_assignable, false>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/meta/meta.detect/is_detected_convertible.pass.cpp b/libcxx/test/std/experimental/utilities/meta/meta.detect/is_detected_convertible.pass.cpp
index a6252b2458b006cdc24cf35897aa5c680d4aaf8f..0944cb2d070d5351d9c2f55d4a274dfa7003dfef 100644
--- a/libcxx/test/std/experimental/utilities/meta/meta.detect/is_detected_convertible.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/meta/meta.detect/is_detected_convertible.pass.cpp
@@ -41,9 +41,11 @@ void test() {
     static_assert( b == ex::is_detected_convertible_v<int, callFoo, T>, "" );
 }
 
-int main () {
+int main(int, char**) {
     test<yesFoo, true>();
     test<noFoo, false>();
     test<wrongFoo, false>();
     test<convertibleFoo, true>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/meta/meta.detect/is_detected_exact.pass.cpp b/libcxx/test/std/experimental/utilities/meta/meta.detect/is_detected_exact.pass.cpp
index c888d436b04efaceea4c8f7f11866f5879cfc0a9..c3156403233763613ae699a10d81f3d82689458b 100644
--- a/libcxx/test/std/experimental/utilities/meta/meta.detect/is_detected_exact.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/meta/meta.detect/is_detected_exact.pass.cpp
@@ -40,9 +40,11 @@ void test() {
     static_assert( b == ex::is_detected_exact_v<int, callFoo, T>, "" );
 }
 
-int main () {
+int main(int, char**) {
     test<yesFoo, true>();
     test<noFoo, false>();
     test<wrongFoo, false>();
     test<convertibleFoo, false>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/nothing_to_do.pass.cpp b/libcxx/test/std/experimental/utilities/nothing_to_do.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/std/experimental/utilities/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/nothing_to_do.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.assignment/assign.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.assignment/assign.pass.cpp
index 481fd4f8fb05181cb74b39253703032310d1c294..078c8c7f0679ff9266150142d539b60f961c3217 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.assignment/assign.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.assignment/assign.pass.cpp
@@ -20,4 +20,6 @@ using std::experimental::propagate_const;
 
 typedef propagate_const<X> P;
 
-int main() { static_assert(!std::is_assignable<P, const P &>::value, ""); }
+int main(int, char**) { static_assert(!std::is_assignable<P, const P &>::value, ""); 
+  return 0;
+}
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.assignment/assign_convertible_element_type.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.assignment/assign_convertible_element_type.pass.cpp
index 7a0fb47ebe03d81495bfeb973926b455105300f7..512b5998138e53eda00ce8c8e5f84f9e732d9f4e 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.assignment/assign_convertible_element_type.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.assignment/assign_convertible_element_type.pass.cpp
@@ -18,7 +18,7 @@
 
 using std::experimental::propagate_const;
 
-int main() {
+int main(int, char**) {
 
   typedef propagate_const<CopyConstructibleFromX> PY;
 
@@ -30,4 +30,6 @@ int main() {
   p = x1;
 
   assert(*p==1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.assignment/assign_convertible_propagate_const.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.assignment/assign_convertible_propagate_const.pass.cpp
index 9b6e7045891b8cdb8d244f0a88bf7b11bcfd6ce0..0da532ab4a283f96ece9b7552c599f736048013b 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.assignment/assign_convertible_propagate_const.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.assignment/assign_convertible_propagate_const.pass.cpp
@@ -21,4 +21,6 @@ using std::experimental::propagate_const;
 typedef propagate_const<X> PX;
 typedef propagate_const<CopyConstructibleFromX> PY;
 
-int main() { static_assert(!std::is_assignable<PY, const PX &>::value, ""); }
+int main(int, char**) { static_assert(!std::is_assignable<PY, const PX &>::value, ""); 
+  return 0;
+}
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.assignment/assign_element_type.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.assignment/assign_element_type.pass.cpp
index d46180ee6f5cc9a2c84e06d4882fa4cacb954b50..896ef9c90b9861840e9a4c4068264d836eb86ce5 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.assignment/assign_element_type.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.assignment/assign_element_type.pass.cpp
@@ -18,7 +18,7 @@
 
 using std::experimental::propagate_const;
 
-int main() {
+int main(int, char**) {
 
   typedef propagate_const<X> P;
 
@@ -30,4 +30,6 @@ int main() {
   p = x1;
 
   assert(*p==1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.assignment/move_assign.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.assignment/move_assign.pass.cpp
index 3aff45980619993c840b3db5275ac2507a77d174..f1546afcc5f28d4d75ebc95423d51b7b32382a3b 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.assignment/move_assign.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.assignment/move_assign.pass.cpp
@@ -18,7 +18,7 @@
 
 using std::experimental::propagate_const;
 
-int main() {
+int main(int, char**) {
 
   typedef propagate_const<X> P;
 
@@ -28,4 +28,6 @@ int main() {
   p2=std::move(p1);
 
   assert(*p2==1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.assignment/move_assign_convertible.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.assignment/move_assign_convertible.pass.cpp
index 5fe39a435b9605d8857366f78705cb449de0a879..dfff0bc9350aa455b408b0f8820f35754729458f 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.assignment/move_assign_convertible.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.assignment/move_assign_convertible.pass.cpp
@@ -18,7 +18,7 @@
 
 using std::experimental::propagate_const;
 
-int main() {
+int main(int, char**) {
 
   typedef propagate_const<X> PX;
   typedef propagate_const<MoveConstructibleFromX> PY;
@@ -29,4 +29,6 @@ int main() {
   py1=std::move(px2);
 
   assert(*py1==2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.assignment/move_assign_convertible_propagate_const.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.assignment/move_assign_convertible_propagate_const.pass.cpp
index b99a25121a0d8cd1321ce885c6e0ae648ccebd16..894910eaa8765618436e94b4c0901078680a5d54 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.assignment/move_assign_convertible_propagate_const.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.assignment/move_assign_convertible_propagate_const.pass.cpp
@@ -18,7 +18,7 @@
 
 using std::experimental::propagate_const;
 
-int main() {
+int main(int, char**) {
 
   typedef propagate_const<X> PX;
   typedef propagate_const<MoveConstructibleFromX> PY;
@@ -29,4 +29,6 @@ int main() {
   py1=std::move(px2);
 
   assert(*py1==2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/convertible_element_type.explicit.ctor.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/convertible_element_type.explicit.ctor.pass.cpp
index 10dc724ab58ede9cb4ec6aa4cb9ee9e93a810fb1..24e27cb6b560824d7aafa1e948ecf07c3db6861a 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/convertible_element_type.explicit.ctor.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/convertible_element_type.explicit.ctor.pass.cpp
@@ -20,8 +20,10 @@ using std::experimental::propagate_const;
 
 typedef propagate_const<ExplicitCopyConstructibleFromX> P;
 
-int main() {
+int main(int, char**) {
   static_assert(!std::is_convertible<P, X>::value, "");
   static_assert(std::is_constructible<P, X>::value, "");
+
+  return 0;
 }
 
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/convertible_element_type.non-explicit.ctor.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/convertible_element_type.non-explicit.ctor.pass.cpp
index ec0ad47e713f1af35c8b9e41149ec1dcb7f10ea6..9cb325db00f1bc4f913562cddef230eb1b1a21e0 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/convertible_element_type.non-explicit.ctor.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/convertible_element_type.non-explicit.ctor.pass.cpp
@@ -25,7 +25,9 @@ void f(const P& p)
   assert(*p==2);
 }
 
-int main() {
+int main(int, char**) {
   f(X(2));
+
+  return 0;
 }
 
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/convertible_propagate_const.copy_ctor.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/convertible_propagate_const.copy_ctor.pass.cpp
index 0320161ba740bfba6a23875be239fe9873ea198f..e440245b5e40f7cc9be1225faf71c74448fcd7f1 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/convertible_propagate_const.copy_ctor.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/convertible_propagate_const.copy_ctor.pass.cpp
@@ -21,5 +21,7 @@ using std::experimental::propagate_const;
 typedef propagate_const<X> PX;
 typedef propagate_const<CopyConstructibleFromX> PY;
 
-int main() { static_assert(!std::is_constructible<PX, PY>::value, ""); }
+int main(int, char**) { static_assert(!std::is_constructible<PX, PY>::value, ""); 
+  return 0;
+}
 
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/convertible_propagate_const.explicit.move_ctor.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/convertible_propagate_const.explicit.move_ctor.pass.cpp
index aa4f1a3ed62d3d3113974b523a7149f0d1570371..3166ebe70c1a196298a75aec805e0138b8e307e5 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/convertible_propagate_const.explicit.move_ctor.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/convertible_propagate_const.explicit.move_ctor.pass.cpp
@@ -21,7 +21,9 @@ using std::experimental::propagate_const;
 typedef propagate_const<X> PX;
 typedef propagate_const<ExplicitMoveConstructibleFromX> PY;
 
-int main() {
+int main(int, char**) {
   static_assert(!std::is_convertible<PY, PX &&>::value, "");
   static_assert(std::is_constructible<PY, PX &&>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/convertible_propagate_const.move_ctor.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/convertible_propagate_const.move_ctor.pass.cpp
index 77f8791a396b5fc7fab944bf679fd031b5573a4a..ea1ac4262f3321c3051fd0de3f5c7e5b81f877ca 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/convertible_propagate_const.move_ctor.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/convertible_propagate_const.move_ctor.pass.cpp
@@ -21,10 +21,12 @@ using std::experimental::propagate_const;
 typedef propagate_const<MoveConstructibleFromX> PY;
 typedef propagate_const<X> PX;
 
-int main() {
+int main(int, char**) {
   PX px(1);
   PY py(std::move(px));
 
   assert(*py==1);
+
+  return 0;
 }
 
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/copy_ctor.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/copy_ctor.pass.cpp
index 0e992a69ba6c1d0db3786ee6c8408d3cd8e036dd..7c0558f398f6606f9f7209f85bb0a01964eda56d 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/copy_ctor.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/copy_ctor.pass.cpp
@@ -20,4 +20,6 @@ using std::experimental::propagate_const;
 
 typedef propagate_const<X> P;
 
-int main() { static_assert(!std::is_constructible<P, const P &>::value, ""); }
+int main(int, char**) { static_assert(!std::is_constructible<P, const P &>::value, ""); 
+  return 0;
+}
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/element_type.explicit.ctor.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/element_type.explicit.ctor.pass.cpp
index 45a3bd363eebc0817434ec1b688a290725981793..aee637620a701ddb8d053418c9dbd1ab958cf3d7 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/element_type.explicit.ctor.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/element_type.explicit.ctor.pass.cpp
@@ -20,8 +20,10 @@ using std::experimental::propagate_const;
 
 typedef propagate_const<ExplicitX> P;
 
-int main() {
+int main(int, char**) {
   static_assert(!std::is_convertible<P, int>::value, "");
   static_assert(std::is_constructible<P, int>::value, "");
+
+  return 0;
 }
 
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/element_type.non-explicit.ctor.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/element_type.non-explicit.ctor.pass.cpp
index b9f6bad69bb607a3c7ce5be75de15e62e4700524..93e50578a97a7e690dec0d18e5f6f5208894a678 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/element_type.non-explicit.ctor.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/element_type.non-explicit.ctor.pass.cpp
@@ -24,4 +24,6 @@ void f(const P&)
 {
 }
 
-int main() { f(2); }
+int main(int, char**) { f(2); 
+  return 0;
+}
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/move_ctor.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/move_ctor.pass.cpp
index 6badeeede2b250a05ca20c51412be946d055e50e..662a605f49c3eabb93a0ddea6b41f9c89786af3d 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/move_ctor.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.ctors/move_ctor.pass.cpp
@@ -18,11 +18,13 @@
 
 using std::experimental::propagate_const;
 
-int main() {
+int main(int, char**) {
 
   typedef propagate_const<X> P;
 
   P p1(2);
   P p2(std::move(p1));
   assert(*p2 == 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.non-const_observers/dereference.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.non-const_observers/dereference.pass.cpp
index 8dffebafa482f5d387a15d656aa87eea4036769a..4e47bac3715c7bc130a6aabebf9e01df219b249a 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.non-const_observers/dereference.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.non-const_observers/dereference.pass.cpp
@@ -27,7 +27,9 @@ constexpr P f()
   return p;
 }
 
-int main() {
+int main(int, char**) {
   constexpr P p = f();
   static_assert(*p==2,"");
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.non-const_observers/explicit_operator_element_type_ptr.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.non-const_observers/explicit_operator_element_type_ptr.pass.cpp
index 53d378391a0e478ef8a224a7d134d35fb5f6fc4d..6ce5d407c58ef5c5dbced2e164568baa260b617b 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.non-const_observers/explicit_operator_element_type_ptr.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.non-const_observers/explicit_operator_element_type_ptr.pass.cpp
@@ -20,4 +20,6 @@ using std::experimental::propagate_const;
 
 typedef propagate_const<X> P;
 
-int main() { static_assert(!std::is_convertible<P, int *>::value, ""); }
+int main(int, char**) { static_assert(!std::is_convertible<P, int *>::value, ""); 
+  return 0;
+}
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.non-const_observers/get.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.non-const_observers/get.pass.cpp
index 04fe4add1ed0e73ef3885dc61b3e47e6e64809e9..1a12c3bdd3d7962494d22564b5dd1311d9958889 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.non-const_observers/get.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.non-const_observers/get.pass.cpp
@@ -27,7 +27,9 @@ constexpr P f()
   return p;
 }
 
-int main() {
+int main(int, char**) {
   constexpr P p = f();
   static_assert(*(p.get())==2,"");
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.non-const_observers/op_arrow.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.non-const_observers/op_arrow.pass.cpp
index d8ea66e8d92b229d7c8f5191c1a87cb430456827..bdc6c693730709150fecefd8f32631179a0ca11a 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.non-const_observers/op_arrow.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.non-const_observers/op_arrow.pass.cpp
@@ -27,7 +27,9 @@ constexpr P f()
   return p;
 }
 
-int main() {
+int main(int, char**) {
   constexpr P p = f();
   static_assert(*(p.operator->())==2,"");
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.non-const_observers/operator_element_type_ptr.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.non-const_observers/operator_element_type_ptr.pass.cpp
index 87b6889096700d91405cfc4758a9c33f76a0e3ef..46244b3917239257b464a3688eda6a6bfdf6954a 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.non-const_observers/operator_element_type_ptr.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.non-const_observers/operator_element_type_ptr.pass.cpp
@@ -18,7 +18,7 @@
 
 using std::experimental::propagate_const;
 
-int main() {
+int main(int, char**) {
 
   typedef propagate_const<XWithImplicitIntStarConversion> P;
 
@@ -31,4 +31,6 @@ int main() {
   *ptr_1 = 2;
 
   assert(*ptr_1==2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.observers/dereference.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.observers/dereference.pass.cpp
index c0a5e1e44e5fce2989f9fd2b2e80a6652528964f..758bca4694ecc6ea21b6c57d622975546193305a 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.observers/dereference.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.observers/dereference.pass.cpp
@@ -18,11 +18,13 @@
 
 using std::experimental::propagate_const;
 
-int main() {
+int main(int, char**) {
 
   typedef propagate_const<X> P;
 
   constexpr P p(1);
 
   static_assert(*p==1,"");
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.observers/explicit_operator_element_type_ptr.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.observers/explicit_operator_element_type_ptr.pass.cpp
index b7dd8f843a522c334551b1a9d8a10890926ef32e..1f98f03d2fa4433747ca168149f1bed9d359f302 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.observers/explicit_operator_element_type_ptr.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.observers/explicit_operator_element_type_ptr.pass.cpp
@@ -20,6 +20,8 @@ using std::experimental::propagate_const;
 
 typedef propagate_const<X> P;
 
-int main() {
+int main(int, char**) {
   static_assert(!std::is_convertible<const P, const int *>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.observers/get.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.observers/get.pass.cpp
index f424fae6456de67918c8d7906c0761770dc818f4..71aea68edc21f68fd5d0b219133a6b358a727d53 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.observers/get.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.observers/get.pass.cpp
@@ -18,11 +18,13 @@
 
 using std::experimental::propagate_const;
 
-int main() {
+int main(int, char**) {
 
   typedef propagate_const<X> P;
 
   constexpr P p(1);
 
   static_assert(*(p.get())==1, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.observers/op_arrow.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.observers/op_arrow.pass.cpp
index 14ba32387f8ea99b3a33a3efd75fc20d00ace062..dcb1b9245570649e05fab1511972ddfb689dc1fa 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.observers/op_arrow.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.observers/op_arrow.pass.cpp
@@ -18,11 +18,13 @@
 
 using std::experimental::propagate_const;
 
-int main() {
+int main(int, char**) {
 
   typedef propagate_const<X> P;
 
   constexpr P p(1);
 
   static_assert(*(p.operator->())==1,"");
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.observers/operator_element_type_ptr.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.observers/operator_element_type_ptr.pass.cpp
index 8c0cb02fc1c8c8ce4c09f89d4522c3641f0fca59..bfd295a1fa0492555374f354988dfed22a976043 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.observers/operator_element_type_ptr.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/propagate_const.observers/operator_element_type_ptr.pass.cpp
@@ -24,4 +24,6 @@ constexpr P p(1);
 
 constexpr const int *ptr_1 = p;
 
-int main() { assert(*ptr_1 == 1); }
+int main(int, char**) { assert(*ptr_1 == 1); 
+  return 0;
+}
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/swap.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/swap.pass.cpp
index e6b94957f9d9bf3bf4b76f004e3e364fd6108954..03b32dd0ec6e2871861155e15e14b8972a9c9002 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/swap.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.class/swap.pass.cpp
@@ -21,11 +21,13 @@ using std::experimental::propagate_const;
 bool swap_called = false;
 void swap(X &, X &) { swap_called = true; }
 
-int main() {
+int main(int, char**) {
   typedef propagate_const<X> P;
   P p1(1);
   P p2(2);
   p1.swap(p2);
   assert(swap_called);
+
+  return 0;
 }
 
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/hash.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/hash.pass.cpp
index 76c683458d8f3fb64159250d6066f7afbe17886a..28ac9c22460c3892a9cabce3bf1834829001c7a6 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/hash.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/hash.pass.cpp
@@ -31,7 +31,7 @@ template <> struct hash<X>
 };
 } // namespace std
 
-int main() {
+int main(int, char**) {
 
   typedef propagate_const<X> P;
 
@@ -40,4 +40,6 @@ int main() {
   auto h = std::hash<P>();
 
   assert(h(p)==99);
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.comparison_function_objects/equal_to.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.comparison_function_objects/equal_to.pass.cpp
index 40f4ae7d519a4d47b1a3bec1af9dff33e6906c09..85e400504768aa1d9735aa47e2ec10cb04a5f1f4 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.comparison_function_objects/equal_to.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.comparison_function_objects/equal_to.pass.cpp
@@ -20,7 +20,7 @@ using std::experimental::propagate_const;
 
 constexpr bool operator==(const X &x1, const X &x2) { return x1.i_ == x2.i_; }
 
-int main() {
+int main(int, char**) {
 
   typedef propagate_const<X> P;
 
@@ -32,4 +32,6 @@ int main() {
 
   assert(c(p1_1,p2_1));
   assert(!c(p1_1,p3_2));
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.comparison_function_objects/greater.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.comparison_function_objects/greater.pass.cpp
index f019f07d12576faf2717fe7c324cb7b29bb131bb..ab7b5e9a21d5ae3be91927459ea9d2dd90da040d 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.comparison_function_objects/greater.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.comparison_function_objects/greater.pass.cpp
@@ -20,7 +20,7 @@ using std::experimental::propagate_const;
 
 constexpr bool operator>(const X &x1, const X &x2) { return x1.i_ > x2.i_; }
 
-int main() {
+int main(int, char**) {
 
   typedef propagate_const<X> P;
 
@@ -34,4 +34,6 @@ int main() {
   assert(!c(p2_1,p1_1));
   assert(!c(p1_1,p3_2));
   assert(c(p3_2,p1_1));
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.comparison_function_objects/greater_equal.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.comparison_function_objects/greater_equal.pass.cpp
index 8f0e0d8cdf9e27781f82c570efee3beb91e81d5a..f30e0e9d22ec706d0fad89479ee13d0deefb1ece 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.comparison_function_objects/greater_equal.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.comparison_function_objects/greater_equal.pass.cpp
@@ -20,7 +20,7 @@ using std::experimental::propagate_const;
 
 constexpr bool operator>=(const X &x1, const X &x2) { return x1.i_ >= x2.i_; }
 
-int main() {
+int main(int, char**) {
 
   typedef propagate_const<X> P;
 
@@ -34,4 +34,6 @@ int main() {
   assert(c(p2_1,p1_1));
   assert(!c(p1_1,p3_2));
   assert(c(p3_2,p1_1));
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.comparison_function_objects/less.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.comparison_function_objects/less.pass.cpp
index 584f52ba6e21746c9d2070a42420e034240137ff..75afd95e115f4b07cf656b96c687da58eaa3738d 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.comparison_function_objects/less.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.comparison_function_objects/less.pass.cpp
@@ -20,7 +20,7 @@ using std::experimental::propagate_const;
 
 constexpr bool operator<(const X &x1, const X &x2) { return x1.i_ < x2.i_; }
 
-int main() {
+int main(int, char**) {
 
   typedef propagate_const<X> P;
 
@@ -34,4 +34,6 @@ int main() {
   assert(!c(p2_1,p1_1));
   assert(c(p1_1,p3_2));
   assert(!c(p3_2,p1_1));
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.comparison_function_objects/less_equal.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.comparison_function_objects/less_equal.pass.cpp
index 4eb25db29b3693b5c657b51b963e48b4d85a94a5..4f6523a320f04f0f20b20ea79e6c54b1048ff79f 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.comparison_function_objects/less_equal.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.comparison_function_objects/less_equal.pass.cpp
@@ -20,7 +20,7 @@ using std::experimental::propagate_const;
 
 constexpr bool operator<=(const X &x1, const X &x2) { return x1.i_ <= x2.i_; }
 
-int main() {
+int main(int, char**) {
 
   typedef propagate_const<X> P;
 
@@ -34,4 +34,6 @@ int main() {
   assert(c(p2_1,p1_1));
   assert(c(p1_1,p3_2));
   assert(!c(p3_2,p1_1));
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.comparison_function_objects/not_equal_to.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.comparison_function_objects/not_equal_to.pass.cpp
index 52eadc4b31df620df2d58e7bdfa43971e08e76b5..1c303ae28dba1fbc27bca0ef36ad5c90ddd77888 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.comparison_function_objects/not_equal_to.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.comparison_function_objects/not_equal_to.pass.cpp
@@ -20,7 +20,7 @@ using std::experimental::propagate_const;
 
 constexpr bool operator!=(const X &x1, const X &x2) { return x1.i_ != x2.i_; }
 
-int main() {
+int main(int, char**) {
 
   typedef propagate_const<X> P;
 
@@ -32,4 +32,6 @@ int main() {
 
   assert(!c(p1_1,p2_1));
   assert(c(p1_1,p3_2));
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.relops/equal.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.relops/equal.pass.cpp
index 696330a426c4cc69cf2100378ba1440c3faf1b82..dafc355a48e4355c7d09ea49a40fe39fd23e0988 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.relops/equal.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.relops/equal.pass.cpp
@@ -33,7 +33,7 @@ constexpr bool operator==(const nullptr_t &, const X &) {
   return false;
 }
 
-int main() {
+int main(int, char**) {
   constexpr X x1_1(1);
   constexpr X x2_1(1);
   constexpr X x3_2(2);
@@ -60,4 +60,6 @@ int main() {
 
   static_assert(!(p1_1==nullptr),"");
   static_assert(!(nullptr==p1_1),"");
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.relops/greater_equal.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.relops/greater_equal.pass.cpp
index 8c214f745c8f99d763fc4bbfea9793a63c8a63f7..36f3747303eb639e91da7d2baaa585eeb9fe1def 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.relops/greater_equal.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.relops/greater_equal.pass.cpp
@@ -24,7 +24,7 @@ constexpr bool operator>=(const X &lhs, const X &rhs) {
   return lhs.i_ >= rhs.i_;
 }
 
-int main() {
+int main(int, char**) {
   constexpr X x1_1(1);
   constexpr X x2_1(1);
   constexpr X x3_2(2);
@@ -50,4 +50,6 @@ int main() {
   static_assert(x1_1 >= p2_1, "");
   static_assert(!(x1_1 >= p3_2), "");
   static_assert(x3_2 >= p1_1, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.relops/greater_than.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.relops/greater_than.pass.cpp
index fb67997859544b4eb92b7d6ed0359e7707e39143..6abadb39b238af51a0ee25de2900a7f5c4238e89 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.relops/greater_than.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.relops/greater_than.pass.cpp
@@ -24,7 +24,7 @@ constexpr bool operator>(const X &lhs, const X &rhs) {
   return lhs.i_ > rhs.i_;
 }
 
-int main() {
+int main(int, char**) {
   constexpr X x1_1(1);
   constexpr X x2_1(1);
   constexpr X x3_2(2);
@@ -46,4 +46,6 @@ int main() {
 
   static_assert(!(x1_1 > p2_1), "");
   static_assert(x3_2 > p1_1, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.relops/less_equal.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.relops/less_equal.pass.cpp
index a1d5b3d9e51fd208e0d5673e4ecd27049422cf12..703faed74e56fd88f00fe98b77d1bc6ab6e2ed83 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.relops/less_equal.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.relops/less_equal.pass.cpp
@@ -24,7 +24,7 @@ constexpr bool operator<=(const X &lhs, const X &rhs) {
   return lhs.i_ <= rhs.i_;
 }
 
-int main() {
+int main(int, char**) {
   constexpr X x1_1(1);
   constexpr X x2_1(1);
   constexpr X x3_2(2);
@@ -51,4 +51,6 @@ int main() {
   static_assert(x1_1 <= p3_2, "");
   static_assert(!(x3_2 <= p1_1), "");
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.relops/less_than.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.relops/less_than.pass.cpp
index 00bf157d9621a23a8c5d3a2584102f23b6c16153..7481418d38439feea5160caec52720353528beb0 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.relops/less_than.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.relops/less_than.pass.cpp
@@ -24,7 +24,7 @@ constexpr bool operator<(const X &lhs, const X &rhs) {
   return lhs.i_ < rhs.i_;
 }
 
-int main() {
+int main(int, char**) {
   constexpr X x1_1(1);
   constexpr X x2_1(1);
   constexpr X x3_2(2);
@@ -46,4 +46,6 @@ int main() {
 
   static_assert(!(p1_1 < x1_1), "");
   static_assert(p1_1 < x3_2, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.relops/not_equal.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.relops/not_equal.pass.cpp
index ba30912dd24acc9ef8a8c556f7d2cd109c48ad74..ebfc623155768198459f209f54427690ff9dcbbb 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.relops/not_equal.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/propagate_const.relops/not_equal.pass.cpp
@@ -33,7 +33,7 @@ constexpr bool operator!=(const nullptr_t &, const X &) {
   return true;
 }
 
-int main() {
+int main(int, char**) {
   constexpr X x1_1(1);
   constexpr X x2_1(1);
   constexpr X x3_2(2);
@@ -58,4 +58,6 @@ int main() {
 
   static_assert(p1_1!=nullptr,"");
   static_assert(nullptr!=p1_1,"");
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/swap.pass.cpp b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/swap.pass.cpp
index 1df35dd8886c163aa90ccbb790079c88f268daf3..84923f78dc1f0144a9dc0be4ed39196c1d7560b3 100644
--- a/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/swap.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/propagate_const/propagate_const.nonmembers/swap.pass.cpp
@@ -21,10 +21,12 @@ using std::experimental::propagate_const;
 bool swap_called = false;
 void swap(X &, X &) { swap_called = true; }
 
-int main() {
+int main(int, char**) {
   typedef propagate_const<X> P;
   P p1(1);
   P p2(2);
   swap(p1, p2);
   assert(swap_called);
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/utility/utility.erased.type/erased_type.pass.cpp b/libcxx/test/std/experimental/utilities/utility/utility.erased.type/erased_type.pass.cpp
index 9c3ac0cc98c992afcf1466377ab05ed64f77b7e1..36bf4f793b4afd9b02058f9786cf97273d45fa08 100644
--- a/libcxx/test/std/experimental/utilities/utility/utility.erased.type/erased_type.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/utility/utility.erased.type/erased_type.pass.cpp
@@ -10,8 +10,10 @@
 
 #include <experimental/utility>
 
-int main()
+int main(int, char**)
 {
   std::experimental::erased_type e;
   ((void)e);
+
+  return 0;
 }
diff --git a/libcxx/test/std/experimental/utilities/utility/utility.synop/includes.pass.cpp b/libcxx/test/std/experimental/utilities/utility/utility.synop/includes.pass.cpp
index 45140f33302d07e79c61590fcce750779460071c..ddf053f2429be5d219b6436c9f8b775b73c81f6d 100644
--- a/libcxx/test/std/experimental/utilities/utility/utility.synop/includes.pass.cpp
+++ b/libcxx/test/std/experimental/utilities/utility/utility.synop/includes.pass.cpp
@@ -14,6 +14,8 @@
 #   error "<experimental/utility> must include <utility>"
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/c.files/cinttypes.pass.cpp b/libcxx/test/std/input.output/file.streams/c.files/cinttypes.pass.cpp
index 675c5751650e5846b20cbbfe665f2b052c509517..e9e32bb67342b553284f60b1f6d4e012035824b7 100644
--- a/libcxx/test/std/input.output/file.streams/c.files/cinttypes.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/c.files/cinttypes.pass.cpp
@@ -877,7 +877,7 @@ template <class T> void test()
     ((void)t); // Prevent unused warning
 }
 
-int main()
+int main(int, char**)
 {
     test<std::int8_t >();
     test<std::int16_t>();
@@ -927,4 +927,6 @@ int main()
     static_assert((std::is_same<decltype(std::strtoumax("", (char**)0, 0)), std::uintmax_t>::value), "");
     static_assert((std::is_same<decltype(std::wcstoimax(L"", (wchar_t**)0, 0)), std::intmax_t>::value), "");
     static_assert((std::is_same<decltype(std::wcstoumax(L"", (wchar_t**)0, 0)), std::uintmax_t>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/c.files/cstdio.pass.cpp b/libcxx/test/std/input.output/file.streams/c.files/cstdio.pass.cpp
index 95a5cb69512181a9802238997343bb6f173d7f81..af8dc97a5e83d20599516f926212219cc837ccff 100644
--- a/libcxx/test/std/input.output/file.streams/c.files/cstdio.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/c.files/cstdio.pass.cpp
@@ -85,7 +85,7 @@
 #pragma clang diagnostic ignored "-Wdeprecated-declarations"
 #endif
 
-int main()
+int main(int, char**)
 {
     std::FILE* fp = 0;
     std::fpos_t fpos = std::fpos_t();
@@ -154,4 +154,6 @@ int main()
     static_assert((std::is_same<decltype(std::puts("")), int>::value), "");
     static_assert((std::is_same<decltype(std::vprintf(" ",va)), int>::value), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/c.files/gets.fail.cpp b/libcxx/test/std/input.output/file.streams/c.files/gets.fail.cpp
index 0772dc9f0fcf2b1e11267b9ef05309755b5e01db..dae0e42ff34a12534e5c09fb0efe3343b43945ac 100644
--- a/libcxx/test/std/input.output/file.streams/c.files/gets.fail.cpp
+++ b/libcxx/test/std/input.output/file.streams/c.files/gets.fail.cpp
@@ -13,7 +13,9 @@
 
 #include <cstdio>
 
-int main()
+int main(int, char**)
 {
     (void) std::gets((char *) NULL);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/filebuf.assign/member_swap.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/filebuf.assign/member_swap.pass.cpp
index b6890b8717de8f85b78bed653a0dc1c9a9257596..9bfcec0a48fa681a4ab0daa3e3b49f0a1a244dd4 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/filebuf.assign/member_swap.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/filebuf.assign/member_swap.pass.cpp
@@ -17,7 +17,7 @@
 #include <cassert>
 #include "platform_support.h"
 
-int main()
+int main(int, char**)
 {
     std::string temp = get_temp_file_name();
     {
@@ -50,4 +50,6 @@ int main()
         assert(f2.sgetc() == L'2');
     }
     std::remove(temp.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/filebuf.assign/move_assign.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/filebuf.assign/move_assign.pass.cpp
index 0acda35b080e5b4f2be5045c046826ae78cad90e..a397e6cc1388b466a663c1020b04c9672ddc0023 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/filebuf.assign/move_assign.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/filebuf.assign/move_assign.pass.cpp
@@ -19,7 +19,7 @@
 #include <cassert>
 #include "platform_support.h"
 
-int main()
+int main(int, char**)
 {
     std::string temp = get_temp_file_name();
     {
@@ -52,4 +52,6 @@ int main()
         assert(f2.sgetc() == L'2');
     }
     std::remove(temp.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/filebuf.assign/nonmember_swap.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/filebuf.assign/nonmember_swap.pass.cpp
index 6fd1d2bb471020bba4af73115b98e640d85a44de..f23c119af90d5ecb1ba4a40b035b2b82bbf67573 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/filebuf.assign/nonmember_swap.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/filebuf.assign/nonmember_swap.pass.cpp
@@ -19,7 +19,7 @@
 #include <cassert>
 #include "platform_support.h"
 
-int main()
+int main(int, char**)
 {
     std::string temp = get_temp_file_name();
     {
@@ -52,4 +52,6 @@ int main()
         assert(f2.sgetc() == L'2');
     }
     std::remove(temp.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/filebuf.cons/default.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/filebuf.cons/default.pass.cpp
index d9230b04527d4b369ed7ee923a86cafbd7590bfa..5efbb03c8a60fddf1c346b84f42e355b41ee3700 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/filebuf.cons/default.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/filebuf.cons/default.pass.cpp
@@ -16,7 +16,7 @@
 #include <fstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::filebuf f;
@@ -26,4 +26,6 @@ int main()
         std::wfilebuf f;
         assert(!f.is_open());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/filebuf.cons/move.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/filebuf.cons/move.pass.cpp
index ad4d37dad635134c7ba0a1f85f74cf9f2b778b01..922e514d7f453436d56542e63ab6cfbd7549a17b 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/filebuf.cons/move.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/filebuf.cons/move.pass.cpp
@@ -19,7 +19,7 @@
 #include <cassert>
 #include "platform_support.h"
 
-int main()
+int main(int, char**)
 {
     std::string temp = get_temp_file_name();
     {
@@ -50,4 +50,6 @@ int main()
         assert(f2.sgetc() == L'2');
     }
     std::remove(temp.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/filebuf.members/open_path.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/filebuf.members/open_path.pass.cpp
index 7f7ce344f8601828e807f2dd611e85500d9ec94b..ea244e1a32d91e1f3ebc7be849b0ad0c14d12c14 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/filebuf.members/open_path.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/filebuf.members/open_path.pass.cpp
@@ -19,7 +19,7 @@
 
 namespace fs = std::filesystem;
 
-int main() {
+int main(int, char**) {
 
   fs::path p = get_temp_file_name();
   {
@@ -52,4 +52,6 @@ int main() {
     assert(f.sbumpc() == L'3');
   }
   remove(p.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/filebuf.members/open_pointer.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/filebuf.members/open_pointer.pass.cpp
index fc3dd6d01cd80d4dd89fa8a4d9b37d655cfd7521..bd662a9f7f825415c0df99caebe8a006b5149740 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/filebuf.members/open_pointer.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/filebuf.members/open_pointer.pass.cpp
@@ -14,7 +14,7 @@
 #include <cassert>
 #include "platform_support.h"
 
-int main()
+int main(int, char**)
 {
     std::string temp = get_temp_file_name();
     {
@@ -47,4 +47,6 @@ int main()
         assert(f.sbumpc() == L'3');
     }
     remove(temp.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/filebuf.virtuals/overflow.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/filebuf.virtuals/overflow.pass.cpp
index 0aeb505c75cc7d9122c8eee9b01bb21b9fb19ec8..6636a42233242f1eb2dec1dfdfb140f019b51854 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/filebuf.virtuals/overflow.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/filebuf.virtuals/overflow.pass.cpp
@@ -36,7 +36,7 @@ struct test_buf
     virtual int_type overflow(int_type c = traits_type::eof()) {return base::overflow(c);}
 };
 
-int main()
+int main(int, char**)
 {
     {
         test_buf<char> f;
@@ -140,4 +140,6 @@ int main()
         assert(f.sbumpc() == -1);
     }
     std::remove("overflow.dat");
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/filebuf.virtuals/pbackfail.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/filebuf.virtuals/pbackfail.pass.cpp
index e711b0c9b5ca2a9479ff224b3413a66c8cc6d7e6..728eec2938e1186288945cb24e4ade0d3639de01 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/filebuf.virtuals/pbackfail.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/filebuf.virtuals/pbackfail.pass.cpp
@@ -32,7 +32,7 @@ struct test_buf
     virtual int_type pbackfail(int_type c = traits_type::eof()) {return base::pbackfail(c);}
 };
 
-int main()
+int main(int, char**)
 {
     {
         test_buf<char> f;
@@ -60,4 +60,6 @@ int main()
             assert(f.sgetc() == '2');
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/filebuf.virtuals/seekoff.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/filebuf.virtuals/seekoff.pass.cpp
index 9126b3396d72d8aa975ca36267cbc618640044d4..6f50357a093d6192d16539426c33e9b02fc6c1fe 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/filebuf.virtuals/seekoff.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/filebuf.virtuals/seekoff.pass.cpp
@@ -18,7 +18,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         char buf[10];
@@ -62,4 +62,6 @@ int main()
         assert(f.sgetc() == L'l');
     }
     std::remove("seekoff.dat");
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/filebuf.virtuals/underflow.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/filebuf.virtuals/underflow.pass.cpp
index 8859b07969d1004efab79293b59fcb74c1d059f0..47760a9162774dd50bbc9485d72d05b0f5da38e2 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/filebuf.virtuals/underflow.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/filebuf.virtuals/underflow.pass.cpp
@@ -36,7 +36,7 @@ struct test_buf
     virtual int_type underflow() {return base::underflow();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         test_buf<char> f;
@@ -121,4 +121,6 @@ int main()
         assert(f.sbumpc() == 0x4E53);
         assert(f.sbumpc() == static_cast<Traits::int_type>(-1));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/filebuf/types.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/filebuf/types.pass.cpp
index e0c95f50a2d84e5c7c7de25a1cd81f56eb3c1c05..40c010f6f70b570dc18907505d268a5a564be0c9 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/filebuf/types.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/filebuf/types.pass.cpp
@@ -22,7 +22,7 @@
 #include <fstream>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::basic_streambuf<char>, std::basic_filebuf<char> >::value), "");
     static_assert((std::is_same<std::basic_filebuf<char>::char_type, char>::value), "");
@@ -30,4 +30,6 @@ int main()
     static_assert((std::is_same<std::basic_filebuf<char>::int_type, std::char_traits<char>::int_type>::value), "");
     static_assert((std::is_same<std::basic_filebuf<char>::pos_type, std::char_traits<char>::pos_type>::value), "");
     static_assert((std::is_same<std::basic_filebuf<char>::off_type, std::char_traits<char>::off_type>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/fstream.assign/member_swap.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/fstream.assign/member_swap.pass.cpp
index 312a68d8307ca5e20e36848d503504dc717f6797..7c94de924d9dc383be365c833a663b5491049e2d 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/fstream.assign/member_swap.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/fstream.assign/member_swap.pass.cpp
@@ -35,7 +35,7 @@ std::pair<std::string, std::string> get_temp_file_names() {
   return names;
 }
 
-int main()
+int main(int, char**)
 {
     std::pair<std::string, std::string> temp_files = get_temp_file_names();
     std::string& temp1 = temp_files.first;
@@ -87,4 +87,6 @@ int main()
     }
     std::remove(temp1.c_str());
     std::remove(temp2.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/fstream.assign/move_assign.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/fstream.assign/move_assign.pass.cpp
index 4ee860a8e9ff37882304d4473ce60184b90a9235..d2cc6ce722f99372c65b23827518d13edd1ee04a 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/fstream.assign/move_assign.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/fstream.assign/move_assign.pass.cpp
@@ -19,7 +19,7 @@
 #include <cassert>
 #include "platform_support.h"
 
-int main()
+int main(int, char**)
 {
     std::string temp = get_temp_file_name();
     {
@@ -46,4 +46,6 @@ int main()
         assert(x == 3.25);
     }
     std::remove(temp.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/fstream.assign/nonmember_swap.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/fstream.assign/nonmember_swap.pass.cpp
index 5a2d826bea61bd586cd2163d5a4d9199043ae4c5..071ca5d85e73485b7ed0de1fb97484d2609ec4f5 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/fstream.assign/nonmember_swap.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/fstream.assign/nonmember_swap.pass.cpp
@@ -37,7 +37,7 @@ std::pair<std::string, std::string> get_temp_file_names() {
   return names;
 }
 
-int main()
+int main(int, char**)
 {
     std::pair<std::string, std::string> temp_files = get_temp_file_names();
     std::string& temp1 = temp_files.first;
@@ -89,4 +89,6 @@ int main()
     }
     std::remove(temp1.c_str());
     std::remove(temp2.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/fstream.cons/default.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/fstream.cons/default.pass.cpp
index ede9fd2393a14e8fff04f39d6ed2d49d4db53732..b38bbb4431f66db84083ebaed502ad8cf6450893 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/fstream.cons/default.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/fstream.cons/default.pass.cpp
@@ -16,7 +16,7 @@
 #include <fstream>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         std::fstream fs;
@@ -24,4 +24,6 @@ int main()
     {
         std::wfstream fs;
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/fstream.cons/move.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/fstream.cons/move.pass.cpp
index a213cc64308e476c9dfbd658987ad7f7b1f69a3a..fb639f1c50b78e4ff851916be4de1a3797618cad 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/fstream.cons/move.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/fstream.cons/move.pass.cpp
@@ -19,7 +19,7 @@
 #include <cassert>
 #include "platform_support.h"
 
-int main()
+int main(int, char**)
 {
     std::string temp = get_temp_file_name();
     {
@@ -44,4 +44,6 @@ int main()
         assert(x == 3.25);
     }
     std::remove(temp.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/fstream.cons/path.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/fstream.cons/path.pass.cpp
index f63ae6bddbb6507bfc05c17a0216c344748c0689..d86b4b6ccf87de71b09d464c71551f8901b27615 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/fstream.cons/path.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/fstream.cons/path.pass.cpp
@@ -23,7 +23,7 @@
 
 namespace fs = std::filesystem;
 
-int main() {
+int main(int, char**) {
   fs::path p = get_temp_file_name();
   {
     std::fstream fs(p, std::ios_base::in | std::ios_base::out |
@@ -45,4 +45,6 @@ int main() {
     assert(x == 3.25);
   }
   std::remove(p.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/fstream.cons/pointer.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/fstream.cons/pointer.pass.cpp
index 07a6a41134f1a6a67ac193a630574426b721fc99..4cade955b9b41644a6cb6218c641d9cdc380355d 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/fstream.cons/pointer.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/fstream.cons/pointer.pass.cpp
@@ -17,7 +17,7 @@
 #include <cassert>
 #include "platform_support.h"
 
-int main()
+int main(int, char**)
 {
     std::string temp = get_temp_file_name();
     {
@@ -40,4 +40,6 @@ int main()
         assert(x == 3.25);
     }
     std::remove(temp.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/fstream.cons/string.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/fstream.cons/string.pass.cpp
index 36546035cce60e03f3000567260a3ae4127d467d..15a2c702393667e383499ae2d13894e14431cc7f 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/fstream.cons/string.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/fstream.cons/string.pass.cpp
@@ -17,7 +17,7 @@
 #include <cassert>
 #include "platform_support.h"
 
-int main()
+int main(int, char**)
 {
     std::string temp = get_temp_file_name();
     {
@@ -42,4 +42,6 @@ int main()
         assert(x == 3.25);
     }
     std::remove(temp.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/fstream.members/close.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/fstream.members/close.pass.cpp
index 818f73be8f094dc7fdf6bc69a93aca74240f5600..94a06c4670cca1f3bcfc37deb5572c43594b2bda 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/fstream.members/close.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/fstream.members/close.pass.cpp
@@ -17,7 +17,7 @@
 #include <cassert>
 #include "platform_support.h"
 
-int main()
+int main(int, char**)
 {
     std::string temp = get_temp_file_name();
     {
@@ -38,4 +38,6 @@ int main()
         assert(!fs.is_open());
     }
     std::remove(temp.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/fstream.members/open_path.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/fstream.members/open_path.pass.cpp
index d6722076a97cf6e10a8d3726591fe961a00aafe6..799829e2bb29199f67387b372d20842581e88100 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/fstream.members/open_path.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/fstream.members/open_path.pass.cpp
@@ -20,7 +20,7 @@
 #include <cassert>
 #include "platform_support.h"
 
-int main() {
+int main(int, char**) {
   std::filesystem::path p = get_temp_file_name();
   {
     std::fstream stream;
@@ -48,4 +48,6 @@ int main() {
     assert(x == 3.25);
   }
   std::remove(p.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/fstream.members/open_pointer.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/fstream.members/open_pointer.pass.cpp
index 07f5c18f561a81389e582c41295e205d2701b5c5..32f1d0096a30125f330b16ca64807bb65088cad7 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/fstream.members/open_pointer.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/fstream.members/open_pointer.pass.cpp
@@ -17,7 +17,7 @@
 #include <cassert>
 #include "platform_support.h"
 
-int main()
+int main(int, char**)
 {
     std::string temp = get_temp_file_name();
     {
@@ -46,4 +46,6 @@ int main()
         assert(x == 3.25);
     }
     std::remove(temp.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/fstream.members/open_string.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/fstream.members/open_string.pass.cpp
index 4bc436b3822b810c7c7964504bbf61099a82958d..90cd5611701bded9c813142e015828c568bcce0b 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/fstream.members/open_string.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/fstream.members/open_string.pass.cpp
@@ -17,7 +17,7 @@
 #include <cassert>
 #include "platform_support.h"
 
-int main()
+int main(int, char**)
 {
     std::string temp = get_temp_file_name();
     {
@@ -46,4 +46,6 @@ int main()
         assert(x == 3.25);
     }
     std::remove(temp.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/fstream.members/rdbuf.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/fstream.members/rdbuf.pass.cpp
index ecbc15bc3e5e688a48b1f4380a1d2723b9b9cd35..0f39fc63b62270d5273dc6c8c41a4fe6dab54c20 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/fstream.members/rdbuf.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/fstream.members/rdbuf.pass.cpp
@@ -16,7 +16,7 @@
 #include <fstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::fstream fs;
@@ -26,4 +26,6 @@ int main()
         std::wfstream fs;
         assert(fs.rdbuf());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/fstream/types.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/fstream/types.pass.cpp
index 3f81e18f4baa95fa7c11d1d0b908d30d738d3828..783cfa3a7369f3286f0269b512c23d140788a57a 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/fstream/types.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/fstream/types.pass.cpp
@@ -22,7 +22,7 @@
 #include <fstream>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::basic_iostream<char>, std::basic_fstream<char> >::value), "");
     static_assert((std::is_same<std::basic_fstream<char>::char_type, char>::value), "");
@@ -30,4 +30,6 @@ int main()
     static_assert((std::is_same<std::basic_fstream<char>::int_type, std::char_traits<char>::int_type>::value), "");
     static_assert((std::is_same<std::basic_fstream<char>::pos_type, std::char_traits<char>::pos_type>::value), "");
     static_assert((std::is_same<std::basic_fstream<char>::off_type, std::char_traits<char>::off_type>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.assign/member_swap.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.assign/member_swap.pass.cpp
index e30a9c0600d60e87e108a459dd2f91c80de6b09a..17b88140d540eee3c4f48f7a5bf7298742581067 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.assign/member_swap.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.assign/member_swap.pass.cpp
@@ -16,7 +16,7 @@
 #include <fstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::ifstream fs1("test.dat");
@@ -38,4 +38,6 @@ int main()
         fs2 >> x;
         assert(x == 3.25);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.assign/move_assign.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.assign/move_assign.pass.cpp
index 9ccd54eec8f014585502c7c5d2f1af4314f33a33..d5fe0984ee6173997aa1228a0741f51024c6282a 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.assign/move_assign.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.assign/move_assign.pass.cpp
@@ -18,7 +18,7 @@
 #include <fstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::ifstream fso("test.dat");
@@ -36,4 +36,6 @@ int main()
         fs >> x;
         assert(x == 3.25);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.assign/nonmember_swap.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.assign/nonmember_swap.pass.cpp
index c008fe50fb7f08e5597fe44c33d428daf82fd7ef..c4cd592d11e28faa1c924cf34cc54ac811d139cf 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.assign/nonmember_swap.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.assign/nonmember_swap.pass.cpp
@@ -17,7 +17,7 @@
 #include <fstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::ifstream fs1("test.dat");
@@ -39,4 +39,6 @@ int main()
         fs2 >> x;
         assert(x == 3.25);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.cons/default.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.cons/default.pass.cpp
index 896903d36d2f2a6c14a2a4834935c432f287203d..7e76d6f8aef88a5a95689264f1619e8aeb6e4abc 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.cons/default.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.cons/default.pass.cpp
@@ -16,7 +16,7 @@
 #include <fstream>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         std::ifstream fs;
@@ -24,4 +24,6 @@ int main()
     {
         std::wifstream fs;
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.cons/move.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.cons/move.pass.cpp
index c7e389e3a70b745b3f7a47f47a877c7e6091c42b..d8a58ac53ceeaa29714cb0242e8b081fb5f054d2 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.cons/move.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.cons/move.pass.cpp
@@ -18,7 +18,7 @@
 #include <fstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::ifstream fso("test.dat");
@@ -34,4 +34,6 @@ int main()
         fs >> x;
         assert(x == 3.25);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.cons/path.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.cons/path.pass.cpp
index 7d6da5b271e336d3d43c804dc7b3919245417f62..8a3a361bb398f0c9d37c7a86e485b880c3fadee7 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.cons/path.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.cons/path.pass.cpp
@@ -22,7 +22,7 @@
 
 namespace fs = std::filesystem;
 
-int main() {
+int main(int, char**) {
   {
     fs::path p;
     static_assert(!std::is_convertible<fs::path, std::ifstream>::value,
@@ -49,4 +49,6 @@ int main() {
   // std::wifstream(const fs::path&, std::ios_base::openmode) is tested in
   // test/std/input.output/file.streams/fstreams/ofstream.cons/string.pass.cpp
   // which creates writable files.
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.cons/pointer.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.cons/pointer.pass.cpp
index 6e0bb2984cce160f650753a7649eef1194297e15..d44b3be75d15b456372c8b8abcdca8cc583904fb 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.cons/pointer.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.cons/pointer.pass.cpp
@@ -16,7 +16,7 @@
 #include <fstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::ifstream fs("test.dat");
@@ -36,4 +36,6 @@ int main()
     // std::wifstream(const char*, std::ios_base::openmode) is tested in
     // test/std/input.output/file.streams/fstreams/ofstream.cons/pointer.pass.cpp
     // which creates writable files.
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.cons/string.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.cons/string.pass.cpp
index a0d90e2559512ccd28499fc4e304387950146eda..c4e979e30c6fc6770959a3021c9a315c748989fc 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.cons/string.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.cons/string.pass.cpp
@@ -16,7 +16,7 @@
 #include <fstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::ifstream fs(std::string("test.dat"));
@@ -36,4 +36,6 @@ int main()
     // std::wifstream(const std::string&, std::ios_base::openmode) is tested in
     // test/std/input.output/file.streams/fstreams/ofstream.cons/string.pass.cpp
     // which creates writable files.
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/close.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/close.pass.cpp
index 609ca4ac158893ba26c2420ed26e3f2f212f6c2c..e72bd548763f11a738b02ac72da77738417a4c1b 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/close.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/close.pass.cpp
@@ -16,7 +16,7 @@
 #include <fstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::ifstream fs;
@@ -34,4 +34,6 @@ int main()
         fs.close();
         assert(!fs.is_open());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/open_path.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/open_path.pass.cpp
index 4432ea5c62160123b6bf24075220c60b08e3486b..bce5fb97dd182714528e174da17932aed6e26dcf 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/open_path.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/open_path.pass.cpp
@@ -19,7 +19,7 @@
 #include <filesystem>
 #include <cassert>
 
-int main() {
+int main(int, char**) {
   {
     std::ifstream fs;
     assert(!fs.is_open());
@@ -44,4 +44,6 @@ int main() {
     fs >> c;
     assert(c == L'r');
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/open_pointer.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/open_pointer.pass.cpp
index 3a12c985291f5d5a96449e695334ce5681f28917..50ec53fdc7827cd2c6d9b694db8d9fa2e9f877a6 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/open_pointer.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/open_pointer.pass.cpp
@@ -16,7 +16,7 @@
 #include <fstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::ifstream fs;
@@ -42,4 +42,6 @@ int main()
         fs >> c;
         assert(c == L'r');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/open_string.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/open_string.pass.cpp
index e6759ed8caedfa63fce0880089c669f5fe149236..155ae0e631d3b7ab24f4105b70f3875f06ade6d6 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/open_string.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/open_string.pass.cpp
@@ -16,7 +16,7 @@
 #include <fstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::ifstream fs;
@@ -42,4 +42,6 @@ int main()
         fs >> c;
         assert(c == L'r');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/rdbuf.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/rdbuf.pass.cpp
index ea64139f13ea14a058b66338c4d2dee6f73d205d..455d2274e2b7c89e8caaba0a6b415bf368c40a6a 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/rdbuf.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/rdbuf.pass.cpp
@@ -16,7 +16,7 @@
 #include <fstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::ifstream fs("test.dat");
@@ -28,4 +28,6 @@ int main()
         std::wfilebuf* fb = fs.rdbuf();
         assert(fb->sgetc() == L'r');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ifstream/types.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ifstream/types.pass.cpp
index a3b441f93867d646f74b0e43e404251476f49308..620c3960895b472f0abc14d67562a3474eddb94d 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ifstream/types.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ifstream/types.pass.cpp
@@ -22,7 +22,7 @@
 #include <fstream>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::basic_istream<char>, std::basic_ifstream<char> >::value), "");
     static_assert((std::is_same<std::basic_ifstream<char>::char_type, char>::value), "");
@@ -30,4 +30,6 @@ int main()
     static_assert((std::is_same<std::basic_ifstream<char>::int_type, std::char_traits<char>::int_type>::value), "");
     static_assert((std::is_same<std::basic_ifstream<char>::pos_type, std::char_traits<char>::pos_type>::value), "");
     static_assert((std::is_same<std::basic_ifstream<char>::off_type, std::char_traits<char>::off_type>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ofstream.assign/member_swap.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ofstream.assign/member_swap.pass.cpp
index 89e32e97f76211109468ac5ec113ad168b4a7fb8..fcfb94ecf20d138e53a423f595c3fb4ca5d6a25b 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ofstream.assign/member_swap.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ofstream.assign/member_swap.pass.cpp
@@ -35,7 +35,7 @@ std::pair<std::string, std::string> get_temp_file_names() {
   return names;
 }
 
-int main()
+int main(int, char**)
 {
     std::pair<std::string, std::string> temp_files = get_temp_file_names();
     std::string& temp1 = temp_files.first;
@@ -95,4 +95,6 @@ int main()
         assert(x == 3.25);
     }
     std::remove(temp2.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ofstream.assign/move_assign.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ofstream.assign/move_assign.pass.cpp
index 1eba0d576a07c998207061532beb09cfdffdce2c..fbc3bf59738c3ff3236861e929baf428f578a1dd 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ofstream.assign/move_assign.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ofstream.assign/move_assign.pass.cpp
@@ -19,7 +19,7 @@
 #include <cassert>
 #include "platform_support.h"
 
-int main()
+int main(int, char**)
 {
     std::string temp = get_temp_file_name();
     {
@@ -48,4 +48,6 @@ int main()
         assert(x == 3.25);
     }
     std::remove(temp.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ofstream.assign/nonmember_swap.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ofstream.assign/nonmember_swap.pass.cpp
index 4190db3a6c1f65812c97c1d6f0ff22c32f67ec3e..3cbf508d94e7607c0369be292035370e668b7434 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ofstream.assign/nonmember_swap.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ofstream.assign/nonmember_swap.pass.cpp
@@ -36,7 +36,7 @@ std::pair<std::string, std::string> get_temp_file_names() {
   return names;
 }
 
-int main()
+int main(int, char**)
 {
     std::pair<std::string, std::string> temp_files = get_temp_file_names();
     std::string& temp1 = temp_files.first;
@@ -96,4 +96,6 @@ int main()
         assert(x == 3.25);
     }
     std::remove(temp2.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ofstream.cons/default.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ofstream.cons/default.pass.cpp
index f87bb1e7965d779de482380c8f0ee8904c803c80..baa4bfe9d8af3e9744e220c8e16bf1806a2edac6 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ofstream.cons/default.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ofstream.cons/default.pass.cpp
@@ -16,7 +16,7 @@
 #include <fstream>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         std::ofstream fs;
@@ -24,4 +24,6 @@ int main()
     {
         std::wofstream fs;
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ofstream.cons/move.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ofstream.cons/move.pass.cpp
index 85fcffee4850901fd6e15af446fb4dbf1e2a96b6..3a3e11e9114ced54dfa57e8dadd574ce0b5e9611 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ofstream.cons/move.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ofstream.cons/move.pass.cpp
@@ -19,7 +19,7 @@
 #include <cassert>
 #include "platform_support.h"
 
-int main()
+int main(int, char**)
 {
     std::string temp = get_temp_file_name();
     {
@@ -46,4 +46,6 @@ int main()
         assert(x == 3.25);
     }
     std::remove(temp.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ofstream.cons/path.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ofstream.cons/path.pass.cpp
index bad7e4f6428190c36573edb333ac319ac5d0bab1..254d696aaf7ab001067745f1aa9e93baf682ab76 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ofstream.cons/path.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ofstream.cons/path.pass.cpp
@@ -22,7 +22,7 @@
 
 namespace fs = std::filesystem;
 
-int main() {
+int main(int, char**) {
   fs::path p = get_temp_file_name();
   {
     static_assert(!std::is_convertible<fs::path, std::ofstream>::value,
@@ -65,4 +65,6 @@ int main() {
     assert(x == 3.25);
   }
   std::remove(p.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ofstream.cons/pointer.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ofstream.cons/pointer.pass.cpp
index 5e4a18d1ed795cca1e46a035a31460abf7d46fab..ce23d5e36f4184b19a130093e08e5fa4722d9325 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ofstream.cons/pointer.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ofstream.cons/pointer.pass.cpp
@@ -17,7 +17,7 @@
 #include <cassert>
 #include "platform_support.h"
 
-int main()
+int main(int, char**)
 {
     std::string temp = get_temp_file_name();
     {
@@ -54,4 +54,6 @@ int main()
         assert(x == 3.25);
     }
     std::remove(temp.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ofstream.cons/string.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ofstream.cons/string.pass.cpp
index 41e739abbe29efb5458b9d4bbe42b23b8fa19a89..c19c278f457dee743f3a3cf1feb3ebc0100ea203 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ofstream.cons/string.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ofstream.cons/string.pass.cpp
@@ -17,7 +17,7 @@
 #include <cassert>
 #include "platform_support.h"
 
-int main()
+int main(int, char**)
 {
     std::string temp = get_temp_file_name();
     {
@@ -54,4 +54,6 @@ int main()
         assert(x == 3.25);
     }
     std::remove(temp.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ofstream.members/close.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ofstream.members/close.pass.cpp
index 00a7041915310daad73a58833e5eb6aa8f340600..3ea39985ecbee01a8fe0ec3f564be9d15df8bb87 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ofstream.members/close.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ofstream.members/close.pass.cpp
@@ -17,7 +17,7 @@
 #include <cassert>
 #include "platform_support.h"
 
-int main()
+int main(int, char**)
 {
     std::string temp = get_temp_file_name();
     {
@@ -38,4 +38,6 @@ int main()
         assert(!fs.is_open());
     }
     std::remove(temp.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ofstream.members/open_path.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ofstream.members/open_path.pass.cpp
index 857b6c68f84deda787565c17ff8769330126dc45..1b783f6d5e89e61e404de94c4237d938c01b9c8d 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ofstream.members/open_path.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ofstream.members/open_path.pass.cpp
@@ -22,7 +22,7 @@
 
 namespace fs = std::filesystem;
 
-int main() {
+int main(int, char**) {
   fs::path p = get_temp_file_name();
   {
     std::ofstream fs;
@@ -58,4 +58,6 @@ int main() {
     assert(c == L'a');
   }
   std::remove(p.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ofstream.members/open_pointer.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ofstream.members/open_pointer.pass.cpp
index 689622741d0c6d893b63f503991a2737a923f18a..5bf58814d26ebe56a454229af360b50269fd3c38 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ofstream.members/open_pointer.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ofstream.members/open_pointer.pass.cpp
@@ -17,7 +17,7 @@
 #include <cassert>
 #include "platform_support.h"
 
-int main()
+int main(int, char**)
 {
     std::string temp = get_temp_file_name();
     {
@@ -54,4 +54,6 @@ int main()
         assert(c == L'a');
     }
     std::remove(temp.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ofstream.members/open_string.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ofstream.members/open_string.pass.cpp
index 6a223891a6b6cf81290db30e3d3203c695a00b9a..52db618e1050d0684e038fd2ce30fc4bade01f4f 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ofstream.members/open_string.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ofstream.members/open_string.pass.cpp
@@ -17,7 +17,7 @@
 #include <cassert>
 #include "platform_support.h"
 
-int main()
+int main(int, char**)
 {
     std::string temp = get_temp_file_name();
     {
@@ -54,4 +54,6 @@ int main()
         assert(c == L'a');
     }
     std::remove(temp.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ofstream.members/rdbuf.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ofstream.members/rdbuf.pass.cpp
index 6e8f2fc369e875b003b97ee6783cb63fbb0e79e9..a7b51fb35d69dfff1189a77f50534cfe5c72871e 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ofstream.members/rdbuf.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ofstream.members/rdbuf.pass.cpp
@@ -17,7 +17,7 @@
 #include <cassert>
 #include "platform_support.h"
 
-int main()
+int main(int, char**)
 {
     std::string temp = get_temp_file_name();
     {
@@ -32,4 +32,6 @@ int main()
         assert(fb->sputc(L'r') == L'r');
     }
     std::remove(temp.c_str());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ofstream/types.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ofstream/types.pass.cpp
index 1feb4214a75800d46df2d6612e069a08d4ee0351..231807195f1c31ae9c673f346f48b17737c89ae4 100644
--- a/libcxx/test/std/input.output/file.streams/fstreams/ofstream/types.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/fstreams/ofstream/types.pass.cpp
@@ -22,7 +22,7 @@
 #include <fstream>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::basic_ostream<char>, std::basic_ofstream<char> >::value), "");
     static_assert((std::is_same<std::basic_ofstream<char>::char_type, char>::value), "");
@@ -30,4 +30,6 @@ int main()
     static_assert((std::is_same<std::basic_ofstream<char>::int_type, std::char_traits<char>::int_type>::value), "");
     static_assert((std::is_same<std::basic_ofstream<char>::pos_type, std::char_traits<char>::pos_type>::value), "");
     static_assert((std::is_same<std::basic_ofstream<char>::off_type, std::char_traits<char>::off_type>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/file.streams/nothing_to_do.pass.cpp b/libcxx/test/std/input.output/file.streams/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/input.output/file.streams/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/input.output/file.streams/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/default.pass.cpp b/libcxx/test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/default.pass.cpp
index 106eb033fd5f5ddccb463e2f80eabd5cf0c553a1..1cb88a3510f686e49c7fb53971c30b067434391b 100644
--- a/libcxx/test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/default.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/default.pass.cpp
@@ -18,7 +18,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main() {
+int main(int, char**) {
   using namespace fs;
   // Default
   {
@@ -27,4 +27,6 @@ int main() {
     directory_entry e;
     assert(e.path() == path());
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/default_const.pass.cpp b/libcxx/test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/default_const.pass.cpp
index 8562312432f8a2b4392d65942aa9b3fc68bc42e8..0f681531a09131f87dd2296a9d037598842286ae 100644
--- a/libcxx/test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/default_const.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/default_const.pass.cpp
@@ -19,7 +19,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main() {
+int main(int, char**) {
   using namespace fs;
   // Default
   {
@@ -28,4 +28,6 @@ int main() {
     const directory_entry e;
     assert(e.path() == path());
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/comparisons.pass.cpp b/libcxx/test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/comparisons.pass.cpp
index 10e8c63b6d0ce6bcfea21840bfe36ee8797341cb..12158349ef86831e7c50a9780656df02b6326e24 100644
--- a/libcxx/test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/comparisons.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/comparisons.pass.cpp
@@ -74,7 +74,9 @@ void test_comparisons_simple() {
   }
 }
 
-int main() {
+int main(int, char**) {
   test_comparison_signatures();
   test_comparisons_simple();
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/path.pass.cpp b/libcxx/test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/path.pass.cpp
index 185b0ef4a245046c0ebca17b236a2225961b8ccb..28bd2752ec0eddfa228b67722a66628dac2d2d45 100644
--- a/libcxx/test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/path.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/path.pass.cpp
@@ -81,7 +81,9 @@ void test_path_conversion() {
   }
 }
 
-int main() {
+int main(int, char**) {
   test_path_method();
   test_path_conversion();
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.directory_iterator/directory_iterator.members/default_ctor.pass.cpp b/libcxx/test/std/input.output/filesystems/class.directory_iterator/directory_iterator.members/default_ctor.pass.cpp
index c318bdb33f68a78f5b960d723a7048eeeb0aa31e..9f60ec286745498848d18dd9b5806b236db253c5 100644
--- a/libcxx/test/std/input.output/filesystems/class.directory_iterator/directory_iterator.members/default_ctor.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.directory_iterator/directory_iterator.members/default_ctor.pass.cpp
@@ -22,7 +22,7 @@
 #include "test_macros.h"
 
 
-int main() {
+int main(int, char**) {
     {
         static_assert(std::is_nothrow_default_constructible<fs::directory_iterator>::value, "");
     }
@@ -31,4 +31,6 @@ int main() {
         const fs::directory_iterator d2;
         assert(d1 == d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.directory_iterator/types.pass.cpp b/libcxx/test/std/input.output/filesystems/class.directory_iterator/types.pass.cpp
index bac6939035cb549df19719fcd37aca4ecf96158b..3932be0216bd6869e5145ac4150f2f119effa227 100644
--- a/libcxx/test/std/input.output/filesystems/class.directory_iterator/types.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.directory_iterator/types.pass.cpp
@@ -25,7 +25,7 @@
 #include "test_macros.h"
 
 
-int main() {
+int main(int, char**) {
     using namespace fs;
     using D = directory_iterator;
     ASSERT_SAME_TYPE(D::value_type, directory_entry);
@@ -33,4 +33,6 @@ int main() {
     ASSERT_SAME_TYPE(D::pointer, const directory_entry*);
     ASSERT_SAME_TYPE(D::reference, const directory_entry&);
     ASSERT_SAME_TYPE(D::iterator_category, std::input_iterator_tag);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.file_status/file_status.cons.pass.cpp b/libcxx/test/std/input.output/filesystems/class.file_status/file_status.cons.pass.cpp
index 53c619bd8e93d8a664ee76a7c083ac5e84dbad13..74fdaaf208440b6e6c4568bd086d00b7382940a2 100644
--- a/libcxx/test/std/input.output/filesystems/class.file_status/file_status.cons.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.file_status/file_status.cons.pass.cpp
@@ -22,7 +22,7 @@
 #include "test_convertible.hpp"
 
 
-int main() {
+int main(int, char**) {
  using namespace fs;
   // Default ctor
   {
@@ -56,4 +56,6 @@ int main() {
     assert(f.type()  == file_type::regular);
     assert(f.permissions() == perms::owner_read);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.file_status/file_status.mods.pass.cpp b/libcxx/test/std/input.output/filesystems/class.file_status/file_status.mods.pass.cpp
index 38573beaca8574d0f301905e5dbbd9a9cdc32696..0ee9f709ba49ae998002b2b5a7f28ab3705d7c49 100644
--- a/libcxx/test/std/input.output/filesystems/class.file_status/file_status.mods.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.file_status/file_status.mods.pass.cpp
@@ -20,7 +20,7 @@
 #include <cassert>
 
 
-int main() {
+int main(int, char**) {
   using namespace fs;
 
   file_status st;
@@ -45,4 +45,6 @@ int main() {
     st.permissions(perms::owner_read);
     assert(st.permissions() == perms::owner_read);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.file_status/file_status.obs.pass.cpp b/libcxx/test/std/input.output/filesystems/class.file_status/file_status.obs.pass.cpp
index 676ceea8dcc9ce33c3cfc949af962aafc9c42ec3..ec4863139f487bd0ee80562f3d80629a702c0cdc 100644
--- a/libcxx/test/std/input.output/filesystems/class.file_status/file_status.obs.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.file_status/file_status.obs.pass.cpp
@@ -20,7 +20,7 @@
 #include <cassert>
 
 
-int main() {
+int main(int, char**) {
   using namespace fs;
 
   const file_status st(file_type::regular, perms::owner_read);
@@ -41,4 +41,6 @@ int main() {
                  "operation must return perms");
     assert(st.permissions() == perms::owner_read);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.filesystem_error/filesystem_error.members.pass.cpp b/libcxx/test/std/input.output/filesystems/class.filesystem_error/filesystem_error.members.pass.cpp
index 075a4137d3ac114043db9b2a25f071150a756946..d9d1a03332d63687211bf5ff01a047321b2389ac 100644
--- a/libcxx/test/std/input.output/filesystems/class.filesystem_error/filesystem_error.members.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.filesystem_error/filesystem_error.members.pass.cpp
@@ -94,8 +94,10 @@ void test_signatures()
   }
 }
 
-int main() {
+int main(int, char**) {
   static_assert(std::is_base_of<std::system_error, fs::filesystem_error>::value, "");
   test_constructors();
   test_signatures();
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.itr/iterator.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.itr/iterator.pass.cpp
index de1e413be2474703100013966e8f798bd5ce98e0..558206d7082f4a48c04add6a4dc7a3860f65f1f8 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.itr/iterator.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.itr/iterator.pass.cpp
@@ -97,8 +97,10 @@ void checkBeginEndBasic() {
 
 }
 
-int main() {
+int main(int, char**) {
   using namespace fs;
   checkIteratorConcepts();
   checkBeginEndBasic(); // See path.decompose.pass.cpp for more tests.
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.append.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.append.pass.cpp
index fb74c8e1946170d515bb51508d7447bf85192565..2f468e595540a002e9c2d68e5355cfc77eac3286 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.append.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.append.pass.cpp
@@ -311,7 +311,7 @@ void test_sfinae()
   }
 }
 
-int main()
+int main(int, char**)
 {
   using namespace fs;
   for (auto const & TC : Cases) {
@@ -335,4 +335,6 @@ int main()
     doAppendSourceAllocTest<wchar_t>(TC);
   }
   test_sfinae();
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.assign/braced_init.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.assign/braced_init.pass.cpp
index eb45c0981d4cfb5b1e2651066e8f3be4806a1e5f..aff89f27bd3963387aaf7bbe151916b6e2526487 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.assign/braced_init.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.assign/braced_init.pass.cpp
@@ -22,9 +22,11 @@
 #include "count_new.hpp"
 
 
-int main() {
+int main(int, char**) {
   using namespace fs;
   path p("abc");
   p = {};
   assert(p.native() == "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.assign/copy.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.assign/copy.pass.cpp
index 04b8f63cbdd24e5eb30defd51d9dcba317ce6c30..9265c70f6f42557ad90112946d286cfa52cc73e8 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.assign/copy.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.assign/copy.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_macros.h"
 
 
-int main() {
+int main(int, char**) {
   using namespace fs;
   static_assert(std::is_copy_assignable<path>::value, "");
   static_assert(!std::is_nothrow_copy_assignable<path>::value, "should not be noexcept");
@@ -32,4 +32,6 @@ int main() {
   assert(p.native() == s);
   assert(p2.native() == s);
   assert(&pref == &p2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.assign/move.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.assign/move.pass.cpp
index 12422c68e42b77cae32e75112e1f1d4358290224..5e5fb1e0e06c981f4bac68ca37c70ec87a19fa0e 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.assign/move.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.assign/move.pass.cpp
@@ -22,7 +22,7 @@
 #include "count_new.hpp"
 
 
-int main() {
+int main(int, char**) {
   using namespace fs;
   static_assert(std::is_nothrow_move_assignable<path>::value, "");
   assert(globalMemCounter.checkOutstandingNewEq(0));
@@ -38,4 +38,6 @@ int main() {
     assert(p.native() != s); // Testing moved from state
     assert(&pref == &p2);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.assign/source.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.assign/source.pass.cpp
index edc0b263844005a1a335e5d61b5929b16b3e24ec..9c23e3b3ebf537257fb60cf08240d4b66fc2fa7b 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.assign/source.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.assign/source.pass.cpp
@@ -228,7 +228,7 @@ void RunStringMoveTest(const char* Expect) {
   }
 }
 
-int main() {
+int main(int, char**) {
   for (auto const& MS : PathList) {
     RunTestCase<char>(MS);
     RunTestCase<wchar_t>(MS);
@@ -237,4 +237,6 @@ int main() {
     RunStringMoveTest(MS);
   }
   test_sfinae();
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.compare.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.compare.pass.cpp
index 41efb7513fa7d95afe1b36981dd15ab7a0cfc755..165e62fe4fe78d6ea4b2295358d028ce99f21b82 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.compare.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.compare.pass.cpp
@@ -184,7 +184,9 @@ void test_compare_elements() {
   }
 }
 
-int main() {
+int main(int, char**) {
   test_compare_basic();
   test_compare_elements();
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.concat.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.concat.pass.cpp
index 842d70543a04141572452ae7b5d0a95ffbfa2f0b..b074e831e15d2d0d982c1bd755ff10d2544fc0ed 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.concat.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.concat.pass.cpp
@@ -325,7 +325,7 @@ void test_sfinae() {
   }
 }
 
-int main()
+int main(int, char**)
 {
   using namespace fs;
   for (auto const & TC : Cases) {
@@ -384,4 +384,6 @@ int main()
     doConcatECharTest<char32_t>(TC);
   }
   test_sfinae();
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.construct/copy.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.construct/copy.pass.cpp
index 789789779a44382f054f15d357b252134b78d9f2..1490c0b9fed8e90e21dc3a762d33681a63062bef 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.construct/copy.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.construct/copy.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_macros.h"
 
 
-int main() {
+int main(int, char**) {
   using namespace fs;
   static_assert(std::is_copy_constructible<path>::value, "");
   static_assert(!std::is_nothrow_copy_constructible<path>::value, "should not be noexcept");
@@ -30,4 +30,6 @@ int main() {
   path p2(p);
   assert(p.native() == s);
   assert(p2.native() == s);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.construct/default.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.construct/default.pass.cpp
index 203c0e5ee613b46410c980524cc3ff7daf10892d..b31728da1f91ac4f6144d549565ad9e9fba3a351 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.construct/default.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.construct/default.pass.cpp
@@ -21,9 +21,11 @@
 #include "test_macros.h"
 
 
-int main() {
+int main(int, char**) {
   using namespace fs;
   static_assert(std::is_nothrow_default_constructible<path>::value, "");
   const path p;
   assert(p.empty());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.construct/move.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.construct/move.pass.cpp
index 4382de14170d87a12d3b9371b7c646ce9b174a47..494a77c3c864826963558dea18b326650267c83b 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.construct/move.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.construct/move.pass.cpp
@@ -22,7 +22,7 @@
 #include "count_new.hpp"
 
 
-int main() {
+int main(int, char**) {
   using namespace fs;
   static_assert(std::is_nothrow_move_constructible<path>::value, "");
   assert(globalMemCounter.checkOutstandingNewEq(0));
@@ -36,4 +36,6 @@ int main() {
     assert(p2.native() == s);
     assert(p.native() != s); // Testing moved from state
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.construct/source.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.construct/source.pass.cpp
index b10d3aa88cda89e0b6bf4f3bbe27d85f203e623e..bcb9986cec919da9dd17e66a11c073f83a8b5ed4 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.construct/source.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.construct/source.pass.cpp
@@ -117,7 +117,7 @@ void test_sfinae() {
   }
 }
 
-int main() {
+int main(int, char**) {
   for (auto const& MS : PathList) {
     RunTestCase<char>(MS);
     RunTestCase<wchar_t>(MS);
@@ -125,4 +125,6 @@ int main() {
     RunTestCase<char32_t>(MS);
   }
   test_sfinae();
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.decompose/empty.fail.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.decompose/empty.fail.cpp
index 481ffcde60f0d6091cbf36075b3341c3d996535a..5248f67515ae37af30c56644f48879de036df22e 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.decompose/empty.fail.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.decompose/empty.fail.cpp
@@ -20,8 +20,10 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     fs::path c;
     c.empty();  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.decompose/path.decompose.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.decompose/path.decompose.pass.cpp
index aa511cdf01427b373e750f4fccaa2b1edea5060d..be9cefb76a847828e2511b8a68b9cab78b246ae6 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.decompose/path.decompose.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.decompose/path.decompose.pass.cpp
@@ -208,8 +208,10 @@ void decompFilenameTest()
   }
 }
 
-int main()
+int main(int, char**)
 {
   decompPathTest();
   decompFilenameTest();
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.gen/lexically_normal.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.gen/lexically_normal.pass.cpp
index 4d295eec5e62e9946ddc1b4c5cb0cf28ce0c546f..f1e616542e9afff11f342254bb626b601cd5e502 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.gen/lexically_normal.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.gen/lexically_normal.pass.cpp
@@ -26,7 +26,7 @@
 #include "filesystem_test_helper.hpp"
 
 
-int main() {
+int main(int, char**) {
   // clang-format off
   struct {
     std::string input;
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.gen/lexically_relative_and_proximate.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.gen/lexically_relative_and_proximate.pass.cpp
index 96fa1597b027ef06ee87078ba4f75ffb2b128565..7e31956ee502f04eb9fb43c70061f903e5c69419 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.gen/lexically_relative_and_proximate.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.gen/lexically_relative_and_proximate.pass.cpp
@@ -27,7 +27,7 @@
 #include "filesystem_test_helper.hpp"
 
 
-int main() {
+int main(int, char**) {
   // clang-format off
   struct {
     std::string input;
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.generic.obs/generic_string_alloc.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.generic.obs/generic_string_alloc.pass.cpp
index 7cb81ca000857700118d6d8e9f857d25f11b9ee4..707a7010ffb4acd9550433fe913c483b50bc285b 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.generic.obs/generic_string_alloc.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.generic.obs/generic_string_alloc.pass.cpp
@@ -33,7 +33,7 @@ MultiStringType longString = MKSTR("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQR
 // generic_string<C, T, A> forwards to string<C, T, A>. Tests for
 // string<C, T, A>() are in "path.native.op/string_alloc.pass.cpp".
 // generic_string is minimally tested here.
-int main()
+int main(int, char**)
 {
   using namespace fs;
   using CharT = wchar_t;
@@ -51,4 +51,6 @@ int main()
     assert(Alloc::alloc_count > 0);
     assert(Alloc::outstanding_alloc() == 1);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.generic.obs/named_overloads.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.generic.obs/named_overloads.pass.cpp
index 2e33769cdb386119031cbf56b7fcfad2caf873c5..04ae673ac4871479ffbda1f1c372d1e87c6f8251 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.generic.obs/named_overloads.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.generic.obs/named_overloads.pass.cpp
@@ -31,7 +31,7 @@
 
 MultiStringType longString = MKSTR("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ/123456789/abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ");
 
-int main()
+int main(int, char**)
 {
   using namespace fs;
   auto const& MS = longString;
@@ -57,4 +57,6 @@ int main()
     std::u32string s = p.generic_u32string();
     assert(s == (const char32_t*)MS);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.modifiers/clear.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.modifiers/clear.pass.cpp
index a224dddfa979479a035fb20b2bdc12737461c8ce..01538539fafeec984327c59d56b4b36ea9e2c499 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.modifiers/clear.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.modifiers/clear.pass.cpp
@@ -24,7 +24,7 @@
 #include "filesystem_test_helper.hpp"
 
 
-int main() {
+int main(int, char**) {
   using namespace fs;
   {
     path p;
@@ -40,4 +40,6 @@ int main() {
     p2.clear();
     assert(p2.empty());
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.modifiers/make_preferred.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.modifiers/make_preferred.pass.cpp
index 43393aba5dab79df58a13100728e5912d610c0a1..4530ef8755497c5416b50ee102abc4c523748f3a 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.modifiers/make_preferred.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.modifiers/make_preferred.pass.cpp
@@ -39,7 +39,7 @@ const MakePreferredTestcase TestCases[] =
     , {"\\foo\\/bar\\/baz\\"}
   };
 
-int main()
+int main(int, char**)
 {
   // This operation is an identity operation on linux.
   using namespace fs;
@@ -50,4 +50,6 @@ int main()
     assert(p.native() == TC.value);
     assert(&Ref == &p);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.modifiers/remove_filename.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.modifiers/remove_filename.pass.cpp
index 42191379dbb105a7e699bb33df5fe0ab31dfe92d..7cb562c227ff85b75f4b09197b81f77b90114119 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.modifiers/remove_filename.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.modifiers/remove_filename.pass.cpp
@@ -57,7 +57,7 @@ const RemoveFilenameTestcase TestCases[] =
     , {"bar/../baz/./file.txt", "bar/../baz/./"}
   };
 
-int main()
+int main(int, char**)
 {
   using namespace fs;
   for (auto const & TC : TestCases) {
@@ -69,4 +69,6 @@ int main()
     assert(&Ref == &p);
     assert(!p.has_filename());
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.modifiers/replace_extension.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.modifiers/replace_extension.pass.cpp
index 70040c48ae55833c074ef5da1e94c6d31752c429..6fec420baa029e4c12ee3a46bb37e76bd74044af 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.modifiers/replace_extension.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.modifiers/replace_extension.pass.cpp
@@ -51,7 +51,7 @@ const ReplaceExtensionTestcase NoArgCases[] =
     , {"foo..cpp", "foo.", ""}
 };
 
-int main()
+int main(int, char**)
 {
   using namespace fs;
   for (auto const & TC : TestCases) {
@@ -68,4 +68,6 @@ int main()
     assert(p == TC.expect);
     assert(&Ref == &p);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.modifiers/replace_filename.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.modifiers/replace_filename.pass.cpp
index 3635352210b7f149193a78a6e6616ad32871feea..8142e7907314b1e7c5e71472486b42247f4a29d1 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.modifiers/replace_filename.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.modifiers/replace_filename.pass.cpp
@@ -47,7 +47,7 @@ const ReplaceFilenameTestcase TestCases[] =
     , {"/foo\\baz/bong", "/foo\\baz/bar", "bar"}
   };
 
-int main()
+int main(int, char**)
 {
   using namespace fs;
   for (auto const & TC : TestCases) {
@@ -67,4 +67,6 @@ int main()
       ASSERT_EQ(p, p2);
     }
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.modifiers/swap.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.modifiers/swap.pass.cpp
index ac623dbfcc522f2fa6bb93ed129b2d5040a64d54..2e9dac5e4386a73973cf92d6ecd3223ed195ae87 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.modifiers/swap.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.modifiers/swap.pass.cpp
@@ -41,7 +41,7 @@ const SwapTestcase TestCases[] =
 #undef LONG_STR1
 #undef LONG_STR2
 
-int main()
+int main(int, char**)
 {
   using namespace fs;
   {
@@ -76,4 +76,6 @@ int main()
     }
     assert(p1 == Val);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.native.obs/c_str.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.native.obs/c_str.pass.cpp
index 3f2fac696da4d14c53a409a2fc23769579b46784..8b35ee8c80adc8ca0a64dd9f2614b7264002ba1c 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.native.obs/c_str.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.native.obs/c_str.pass.cpp
@@ -23,7 +23,7 @@
 #include "filesystem_test_helper.hpp"
 
 
-int main()
+int main(int, char**)
 {
   using namespace fs;
   const char* const value = "hello world";
@@ -38,4 +38,6 @@ int main()
     assert(p.c_str() == str_value);
     assert(p.native().c_str() == p.c_str());
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.native.obs/named_overloads.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.native.obs/named_overloads.pass.cpp
index 0d747b188959cbe7c4e9a952b9d5d866ae6ac559..c06de9795e3c183e3d6122392e7d7941e3ecd9dd 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.native.obs/named_overloads.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.native.obs/named_overloads.pass.cpp
@@ -32,7 +32,7 @@
 
 MultiStringType longString = MKSTR("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ/123456789/abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ");
 
-int main()
+int main(int, char**)
 {
   using namespace fs;
   auto const& MS = longString;
@@ -58,4 +58,6 @@ int main()
     std::u32string s = p.u32string();
     assert(s == (const char32_t*)MS);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.native.obs/native.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.native.obs/native.pass.cpp
index 14feaf13e8e56f2efb796b41e10a57e818621946..3b88b5d6c64d5e112280154162ef82dfac688e4f 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.native.obs/native.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.native.obs/native.pass.cpp
@@ -22,7 +22,7 @@
 #include "filesystem_test_helper.hpp"
 
 
-int main()
+int main(int, char**)
 {
   using namespace fs;
   const char* const value = "hello world";
@@ -35,4 +35,6 @@ int main()
     path p(value);
     assert(p.native() == value);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.native.obs/operator_string.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.native.obs/operator_string.pass.cpp
index 53fdcc160349162927de63bc7f20b0e490fd2ffc..9f0069051fdc14cb38b03ee202a0abf28328b67a 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.native.obs/operator_string.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.native.obs/operator_string.pass.cpp
@@ -23,7 +23,7 @@
 #include "filesystem_test_helper.hpp"
 
 
-int main()
+int main(int, char**)
 {
   using namespace fs;
   using string_type = path::string_type;
@@ -42,4 +42,6 @@ int main()
     assert(s == value);
     assert(p == value);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.native.obs/string_alloc.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.native.obs/string_alloc.pass.cpp
index 86453f8d0b9c52179738383253b84e58397db07c..4ace380b873d84f4c54f4784690cd8343dc10657 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.native.obs/string_alloc.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.native.obs/string_alloc.pass.cpp
@@ -116,7 +116,7 @@ void doLongStringTest(MultiStringType const& MS) {
   /////////////////////////////////////////////////////////////////////////////
 }
 
-int main()
+int main(int, char**)
 {
   using namespace fs;
   {
@@ -133,4 +133,6 @@ int main()
     doLongStringTest<char16_t>(S);
     doLongStringTest<char32_t>(S);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.query/tested_in_path_decompose.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.query/tested_in_path_decompose.pass.cpp
index d825788506b6e158e75103ecfa199c17e4b4e68b..32c37e7f7a5a447f297e9e8d3f9416c0ba267a34 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.query/tested_in_path_decompose.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.query/tested_in_path_decompose.pass.cpp
@@ -28,4 +28,6 @@
 // bool is_relative() const;
 
 // tested in path.decompose
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/append_op.fail.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/append_op.fail.cpp
index 7b5082c8f8da420c8259c3d7b35dd145326581fe..bcc4758f45ff1f867257e6be9f13a1ea61987ac9 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/append_op.fail.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/append_op.fail.cpp
@@ -20,7 +20,9 @@ struct ConvToPath {
   }
 };
 
-int main() {
+int main(int, char**) {
   ConvToPath LHS, RHS;
   (void)(LHS / RHS); // expected-error {{invalid operands to binary expression}}
+
+  return 0;
 }
\ No newline at end of file
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/append_op.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/append_op.pass.cpp
index 2c7042e9b7bd0ea5e7c58ff9bf926a50d66d8455..67af37686df59493091308bb9e21f4c272923cd4 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/append_op.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/append_op.pass.cpp
@@ -20,7 +20,7 @@
 #include "filesystem_test_helper.hpp"
 
 // This is mainly tested via the member append functions.
-int main()
+int main(int, char**)
 {
   using namespace fs;
   path p1("abc");
@@ -30,4 +30,6 @@ int main()
 
   path p4 = p1 / "def";
   assert(p4 == "abc/def");
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/comparison_ops.fail.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/comparison_ops.fail.cpp
index 287e315237b1c284bbe43a62e7fe498faba22ae1..8f1732186d8956348769412e36370bea51cbbe28 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/comparison_ops.fail.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/comparison_ops.fail.cpp
@@ -21,7 +21,7 @@ struct ConvToPath {
   }
 };
 
-int main() {
+int main(int, char**) {
   ConvToPath LHS, RHS;
   (void)(LHS == RHS); // expected-error {{invalid operands to binary expression}}
   (void)(LHS != RHS); // expected-error {{invalid operands to binary expression}}
@@ -29,4 +29,6 @@ int main() {
   (void)(LHS <= RHS); // expected-error {{invalid operands to binary expression}}
   (void)(LHS > RHS); // expected-error {{invalid operands to binary expression}}
   (void)(LHS >= RHS); // expected-error {{invalid operands to binary expression}}
+
+  return 0;
 }
\ No newline at end of file
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/comparison_ops_tested_elsewhere.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/comparison_ops_tested_elsewhere.pass.cpp
index 3728db5f224b538efcefd2161270eae6f470252a..c61a5a0254ccdb328ec37c1276e4398c773e13db 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/comparison_ops_tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/comparison_ops_tested_elsewhere.pass.cpp
@@ -10,4 +10,6 @@
 
 // The comparison operators are tested as part of [path.compare]
 // in class.path/path.members/path.compare.pass.cpp
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/hash_value_tested_elswhere.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/hash_value_tested_elswhere.pass.cpp
index 6cf310be88b3b6da161252f0fc53ba90afc58792..49d28daf98f7f9c68f4c84d42abdd7ab93dc1949 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/hash_value_tested_elswhere.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/hash_value_tested_elswhere.pass.cpp
@@ -10,4 +10,6 @@
 
 // The "hash_value" function is tested as part of [path.compare]
 // in class.path/path.members/path.compare.pass.cpp
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/path.factory.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/path.factory.pass.cpp
index 54d0799d92ac5c04e6eea0adc046426ea46f331d..557849ca8e6c8f87aff7b52ade6cb3362b094185 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/path.factory.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/path.factory.pass.cpp
@@ -25,7 +25,7 @@
 #include "filesystem_test_helper.hpp"
 
 
-int main()
+int main(int, char**)
 {
   using namespace fs;
   const char* In1 = "abcd/efg";
@@ -48,4 +48,6 @@ int main()
     path p = fs::u8path(In3, In3End);
     assert(p == In1);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/path.io.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/path.io.pass.cpp
index 375e45da8e663db351e909ca2df8c605136577e1..31eea925a5d0e49af4f25d24dcb8f6d9e708b3eb 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/path.io.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/path.io.pass.cpp
@@ -88,10 +88,12 @@ void test_LWG2989() {
   static_assert(!is_istreamable<decltype(std::wcin), std::string>::value, "");
 }
 
-int main() {
+int main(int, char**) {
   doIOTest<char>();
   doIOTest<wchar_t>();
   //doIOTest<char16_t>();
   //doIOTest<char32_t>();
   test_LWG2989();
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/path.io.unicode_bug.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/path.io.unicode_bug.pass.cpp
index 2072a9450fbcb275d43a368b1dfe23740ed060a8..c5bb6bf120f776bce8c6fe4372defba2a990d94e 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/path.io.unicode_bug.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/path.io.unicode_bug.pass.cpp
@@ -62,7 +62,9 @@ void doIOTest() {
 }
 
 
-int main() {
+int main(int, char**) {
   doIOTest<char16_t>();
   doIOTest<char32_t>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/swap.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/swap.pass.cpp
index 66d854f00b295c4736a69339e8e4c3b841d7fed3..51bb03e9f7cf91dbd1b25364a41be931ae40c12c 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/swap.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.nonmember/swap.pass.cpp
@@ -22,7 +22,7 @@
 
 
 // NOTE: this is tested in path.members/path.modifiers via the member swap.
-int main()
+int main(int, char**)
 {
   using namespace fs;
   const char* value1 = "foo/bar/baz";
@@ -45,4 +45,6 @@ int main()
     assert(p1.native() == value1);
     assert(p2.native() == value2);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/class.path/synop.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/synop.pass.cpp
index 9b91651e08f049c7b77cc7e1e39609fdc32d0085..8aa186e32aeb00c15fd4189ffa2eeee4ba8ee98b 100644
--- a/libcxx/test/std/input.output/filesystems/class.path/synop.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/synop.pass.cpp
@@ -23,7 +23,7 @@
 #include "test_macros.h"
 
 
-int main() {
+int main(int, char**) {
   using namespace fs;
   ASSERT_SAME_TYPE(path::value_type, char);
   ASSERT_SAME_TYPE(path::string_type, std::basic_string<path::value_type>);
@@ -34,4 +34,6 @@ int main() {
     const char* dummy = &path::preferred_separator;
     ((void)dummy);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/fs.enum/enum.copy_options.pass.cpp b/libcxx/test/std/input.output/filesystems/fs.enum/enum.copy_options.pass.cpp
index 25f63a92b33137a9c6834682071dbc3e9803301a..b949960df117902711a7dcba2fc9f776bdead5e5 100644
--- a/libcxx/test/std/input.output/filesystems/fs.enum/enum.copy_options.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/fs.enum/enum.copy_options.pass.cpp
@@ -22,7 +22,7 @@
 
 constexpr fs::copy_options ME(int val) { return static_cast<fs::copy_options>(val); }
 
-int main() {
+int main(int, char**) {
   typedef fs::copy_options E;
   static_assert(std::is_enum<E>::value, "");
 
@@ -59,4 +59,6 @@ int main() {
           E::create_symlinks     == ME(128) &&
           E::create_hard_links   == ME(256),
         "Expected enumeration values do not match");
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/fs.enum/enum.directory_options.pass.cpp b/libcxx/test/std/input.output/filesystems/fs.enum/enum.directory_options.pass.cpp
index 54574f720f5ccd9fcfec172fa70dd2014a7288fb..43b0945978e069b90e6ff71ad1e143f0b126fd88 100644
--- a/libcxx/test/std/input.output/filesystems/fs.enum/enum.directory_options.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/fs.enum/enum.directory_options.pass.cpp
@@ -23,7 +23,7 @@
 
 constexpr fs::directory_options ME(int val) { return static_cast<fs::directory_options>(val); }
 
-int main() {
+int main(int, char**) {
   typedef fs::directory_options E;
   static_assert(std::is_enum<E>::value, "");
 
@@ -41,4 +41,6 @@ int main() {
         E::skip_permission_denied   == ME(2),
         "Expected enumeration values do not match");
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/fs.enum/enum.file_type.pass.cpp b/libcxx/test/std/input.output/filesystems/fs.enum/enum.file_type.pass.cpp
index d2162d083834d97b6ffe834a6d7ada5600bfc00d..c1f16079a5d8aa48ab215f6218c26bcba6d35b64 100644
--- a/libcxx/test/std/input.output/filesystems/fs.enum/enum.file_type.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/fs.enum/enum.file_type.pass.cpp
@@ -21,7 +21,7 @@
 
 constexpr fs::file_type ME(int val) { return static_cast<fs::file_type>(val); }
 
-int main() {
+int main(int, char**) {
   typedef fs::file_type E;
   static_assert(std::is_enum<E>::value, "");
 
@@ -43,4 +43,6 @@ int main() {
           E::socket == ME(7) &&
           E::unknown == ME(8),
         "Expected enumeration values do not match");
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/fs.enum/enum.path.format.pass.cpp b/libcxx/test/std/input.output/filesystems/fs.enum/enum.path.format.pass.cpp
index fc11e8a9c1f4f1e9fcda7fc2ebe7dcb3a02a7157..d60225d4ff6586c816a7ab27523b00be2bea389f 100644
--- a/libcxx/test/std/input.output/filesystems/fs.enum/enum.path.format.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/fs.enum/enum.path.format.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main() {
+int main(int, char**) {
   typedef fs::path::format E;
   static_assert(std::is_enum<E>::value, "");
 
@@ -34,4 +34,6 @@ int main() {
           E::auto_format   != E::generic_format &&
           E::native_format != E::generic_format,
         "Expected enumeration values are not unique");
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/fs.enum/enum.perm_options.pass.cpp b/libcxx/test/std/input.output/filesystems/fs.enum/enum.perm_options.pass.cpp
index 117c35875e09f08fff4a9990418dabb5efc3e4bd..1fd353d041fbac869b6ec9769b82f41470651091 100644
--- a/libcxx/test/std/input.output/filesystems/fs.enum/enum.perm_options.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/fs.enum/enum.perm_options.pass.cpp
@@ -25,7 +25,7 @@ constexpr fs::perm_options ME(int val) {
   return static_cast<fs::perm_options>(val);
 }
 
-int main() {
+int main(int, char**) {
   typedef fs::perm_options E;
   static_assert(std::is_enum<E>::value, "");
 
@@ -44,4 +44,6 @@ int main() {
         E::remove   == ME(4) &&
         E::nofollow == ME(8),
         "Expected enumeration values do not match");
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/fs.enum/enum.perms.pass.cpp b/libcxx/test/std/input.output/filesystems/fs.enum/enum.perms.pass.cpp
index e043c87e5c17b8cd04425271ea2a8f398729af62..93b5278fdd4814a70200aac72bfde644f3b90172 100644
--- a/libcxx/test/std/input.output/filesystems/fs.enum/enum.perms.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/fs.enum/enum.perms.pass.cpp
@@ -23,7 +23,7 @@
 
 constexpr fs::perms ME(int val) { return static_cast<fs::perms>(val); }
 
-int main() {
+int main(int, char**) {
   typedef fs::perms E;
   static_assert(std::is_enum<E>::value, "");
 
@@ -60,4 +60,6 @@ int main() {
         E::mask         == ME(07777) &&
         E::unknown      == ME(0xFFFF),
         "Expected enumeration values do not match");
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/fs.error.report/tested_elsewhere.pass.cpp b/libcxx/test/std/input.output/filesystems/fs.error.report/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/input.output/filesystems/fs.error.report/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/fs.error.report/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/fs.filesystem.synopsis/file_time_type.pass.cpp b/libcxx/test/std/input.output/filesystems/fs.filesystem.synopsis/file_time_type.pass.cpp
index 6606c9a27cf18e0b9dd03146e19965a930271f4d..e88ef1d12c42ee65254254fd941b872a717fad87 100644
--- a/libcxx/test/std/input.output/filesystems/fs.filesystem.synopsis/file_time_type.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/fs.filesystem.synopsis/file_time_type.pass.cpp
@@ -39,7 +39,9 @@ void test_time_point_resolution_and_range() {
   ASSERT_SAME_TYPE(Period, std::nano);
 }
 
-int main() {
+int main(int, char**) {
   test_trivial_clock();
   test_time_point_resolution_and_range();
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/fs.op.funcs/fs.op.weakly_canonical/weakly_canonical.pass.cpp b/libcxx/test/std/input.output/filesystems/fs.op.funcs/fs.op.weakly_canonical/weakly_canonical.pass.cpp
index c655490acf89e09c58ee495f4a03ef44a7f1ec68..94a8e13bc0881311198583ab680883a57c6ab219 100644
--- a/libcxx/test/std/input.output/filesystems/fs.op.funcs/fs.op.weakly_canonical/weakly_canonical.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/fs.op.funcs/fs.op.weakly_canonical/weakly_canonical.pass.cpp
@@ -25,7 +25,7 @@
 #include "filesystem_test_helper.hpp"
 
 
-int main() {
+int main(int, char**) {
   // clang-format off
   struct {
     std::string input;
diff --git a/libcxx/test/std/input.output/filesystems/fs.req.macros/feature_macro.pass.cpp b/libcxx/test/std/input.output/filesystems/fs.req.macros/feature_macro.pass.cpp
index aa1933cc6b1fb7c062bc106ce5de215fe0635aaf..dad1868bee315cb57e147652f7a29de5858c068c 100644
--- a/libcxx/test/std/input.output/filesystems/fs.req.macros/feature_macro.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/fs.req.macros/feature_macro.pass.cpp
@@ -25,4 +25,6 @@
 #endif
 #endif
 
-int main() { }
+int main(int, char**) { 
+  return 0;
+}
diff --git a/libcxx/test/std/input.output/filesystems/fs.req.namespace/namespace.fail.cpp b/libcxx/test/std/input.output/filesystems/fs.req.namespace/namespace.fail.cpp
index e3030995de1484800e956fdbb86f3a80253e9744..641621e73384e65db6136496baceda32562449f4 100644
--- a/libcxx/test/std/input.output/filesystems/fs.req.namespace/namespace.fail.cpp
+++ b/libcxx/test/std/input.output/filesystems/fs.req.namespace/namespace.fail.cpp
@@ -23,6 +23,8 @@ using namespace std::filesystem;
 // expected-error@-5 {{expected namespace name}}
 #endif
 
-int main() {
+int main(int, char**) {
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/filesystems/fs.req.namespace/namespace.pass.cpp b/libcxx/test/std/input.output/filesystems/fs.req.namespace/namespace.pass.cpp
index 96ba646ffbeae83faac7b33497c385b83bf206cd..6586433690106e033091f5410e6b2ac82facf0e7 100644
--- a/libcxx/test/std/input.output/filesystems/fs.req.namespace/namespace.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/fs.req.namespace/namespace.pass.cpp
@@ -17,9 +17,11 @@
 
 using namespace std::filesystem;
 
-int main() {
+int main(int, char**) {
   static_assert(std::is_same<
           path,
           std::filesystem::path
       >::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/input.output.general/nothing_to_do.pass.cpp b/libcxx/test/std/input.output/input.output.general/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/input.output/input.output.general/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/input.output/input.output.general/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/ext.manip/get_money.pass.cpp b/libcxx/test/std/input.output/iostream.format/ext.manip/get_money.pass.cpp
index 0a68da1c44fcd8049b1273d8eb54c3a868c170b8..cb1f2c68ee5ce940700560ab68b37b999bb45b1f 100644
--- a/libcxx/test/std/input.output/iostream.format/ext.manip/get_money.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/ext.manip/get_money.pass.cpp
@@ -38,7 +38,7 @@ public:
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb("  -$1,234,567.89");
@@ -72,4 +72,6 @@ int main()
         is >> std::get_money(x, true);
         assert(x == -123456789);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/ext.manip/get_time.pass.cpp b/libcxx/test/std/input.output/iostream.format/ext.manip/get_time.pass.cpp
index 05ed05c39f722dc5e25f6105a4e6c23d557aeefa..ebf62c08e720b84385edc3397ddfdc2fd6a5b3f0 100644
--- a/libcxx/test/std/input.output/iostream.format/ext.manip/get_time.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/ext.manip/get_time.pass.cpp
@@ -38,7 +38,7 @@ public:
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb("  Sat Dec 31 23:55:59 2061");
@@ -72,4 +72,6 @@ int main()
         assert(is.eof());
         assert(!is.fail());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/ext.manip/put_money.pass.cpp b/libcxx/test/std/input.output/iostream.format/ext.manip/put_money.pass.cpp
index 0dffdfb5fe1750eac1ead6ec3c5a5d081e0be83f..d924d77bc7d84444f860778a185a5612d6535a6c 100644
--- a/libcxx/test/std/input.output/iostream.format/ext.manip/put_money.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/ext.manip/put_money.pass.cpp
@@ -50,7 +50,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb;
@@ -88,4 +88,6 @@ int main()
         os << std::put_money(x, true);
         assert(sb.str() == L"-USD 1,234,567.89");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/ext.manip/put_time.pass.cpp b/libcxx/test/std/input.output/iostream.format/ext.manip/put_time.pass.cpp
index 7dcbcf4883874cce872cea83ecdab9bbe4e09677..faa99e0634386e75b2063b52e90e6a04c380768b 100644
--- a/libcxx/test/std/input.output/iostream.format/ext.manip/put_time.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/ext.manip/put_time.pass.cpp
@@ -50,7 +50,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb;
@@ -83,4 +83,6 @@ int main()
         os << std::put_time(&t, L"%a %b %d %H:%M:%S %Y");
         assert(sb.str() == L"Sat Dec 31 23:55:59 2061");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/iostreamclass/iostream.assign/member_swap.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/iostreamclass/iostream.assign/member_swap.pass.cpp
index b9505c76ed0522e37b2e16f740fca051c40c72a2..44b394b8fb0139430167668c4c0796d06da6c815 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/iostreamclass/iostream.assign/member_swap.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/iostreamclass/iostream.assign/member_swap.pass.cpp
@@ -33,7 +33,7 @@ struct test_iostream
     void swap(test_iostream& s) {base::swap(s);}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb1;
@@ -81,4 +81,6 @@ int main()
         assert(is2.precision() == 6);
         assert(is2.getloc().name() == "C");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/iostreamclass/iostream.assign/move_assign.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/iostreamclass/iostream.assign/move_assign.pass.cpp
index f53411270b5501c56e609e42a729f93218becd65..c7918ec8d73de141f87e389972ca0ceda03205d2 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/iostreamclass/iostream.assign/move_assign.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/iostreamclass/iostream.assign/move_assign.pass.cpp
@@ -38,7 +38,7 @@ struct test_iostream
 };
 
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb1;
@@ -86,4 +86,6 @@ int main()
         assert(is2.precision() == 6);
         assert(is2.getloc().name() == "C");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/iostreamclass/iostream.cons/move.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/iostreamclass/iostream.cons/move.pass.cpp
index 2dc91457ce799646ec92d31eb5a466b0c576ce08..611a7a670d2675aa726fe22208f21cbdbb008a93 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/iostreamclass/iostream.cons/move.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/iostreamclass/iostream.cons/move.pass.cpp
@@ -38,7 +38,7 @@ struct test_iostream
 };
 
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb;
@@ -72,4 +72,6 @@ int main()
         assert(is.precision() == 6);
         assert(is.getloc().name() == "C");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/iostreamclass/iostream.cons/streambuf.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/iostreamclass/iostream.cons/streambuf.pass.cpp
index bf6fe65badc260a2f7e0f16d64ed1d6394a2bb5f..c12abc0e2dcb0f54c813e1382ce0b2e8686de3d1 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/iostreamclass/iostream.cons/streambuf.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/iostreamclass/iostream.cons/streambuf.pass.cpp
@@ -23,7 +23,7 @@ struct testbuf
     testbuf() {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb;
@@ -51,4 +51,6 @@ int main()
         assert(is.getloc().name() == "C");
         assert(is.gcount() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/iostreamclass/iostream.dest/nothing_to_do.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/iostreamclass/iostream.dest/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/iostreamclass/iostream.dest/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/iostreamclass/iostream.dest/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/iostreamclass/types.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/iostreamclass/types.pass.cpp
index ef7dcd24e3bbaead84491c38470026807187c18a..46d7a16aac74c90876c436065765b0c23c617d57 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/iostreamclass/types.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/iostreamclass/types.pass.cpp
@@ -24,7 +24,7 @@
 #include <istream>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::basic_istream<char>, std::basic_iostream<char> >::value), "");
     static_assert((std::is_base_of<std::basic_ostream<char>, std::basic_iostream<char> >::value), "");
@@ -33,4 +33,6 @@ int main()
     static_assert((std::is_same<std::basic_iostream<char>::int_type, std::char_traits<char>::int_type>::value), "");
     static_assert((std::is_same<std::basic_iostream<char>::pos_type, std::char_traits<char>::pos_type>::value), "");
     static_assert((std::is_same<std::basic_iostream<char>::off_type, std::char_traits<char>::off_type>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/bool.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/bool.pass.cpp
index 570aeaa393ceda664a85a27499e465eddda344a7..799ec5eaeb534a640d0a695a2febf3e7bea26bd2 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/bool.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/bool.pass.cpp
@@ -40,7 +40,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::istream is((std::streambuf*)0);
@@ -75,4 +75,6 @@ int main()
         assert(!is.eof());
         assert(!is.fail());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/double.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/double.pass.cpp
index 6a285556d815ee0b589f829b1f77b127786cedbb..9f9872d9ef860eb2cbc21e7c193d2c1d4ef49e96 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/double.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/double.pass.cpp
@@ -40,7 +40,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::istream is((std::streambuf*)0);
@@ -75,4 +75,6 @@ int main()
         assert(!is.eof());
         assert(!is.fail());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/float.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/float.pass.cpp
index da93a3bafc23493e2a28557e26a36722c4f88f76..c2b937a89cfe0c061a2e9ec842f43e7a327d3ec2 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/float.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/float.pass.cpp
@@ -40,7 +40,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::istream is((std::streambuf*)0);
@@ -75,4 +75,6 @@ int main()
         assert(!is.eof());
         assert(!is.fail());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/int.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/int.pass.cpp
index f683bee45da1c6a1519044311367947c3c5dd091..702287be79ec72e9cc407c0fae7d035d0f43edfd 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/int.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/int.pass.cpp
@@ -41,7 +41,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::istream is((std::streambuf*)0);
@@ -76,4 +76,6 @@ int main()
         assert(!is.eof());
         assert( is.fail());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/long.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/long.pass.cpp
index 0c8eee50d75005a9b13779b7a4f0b5da3bfbdb2e..9f9118cbcdc28a605c8c2bb8df62a45e89f67b1b 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/long.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/long.pass.cpp
@@ -40,7 +40,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::istream is((std::streambuf*)0);
@@ -75,4 +75,6 @@ int main()
         assert(!is.eof());
         assert(!is.fail());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/long_double.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/long_double.pass.cpp
index 2fff174cbccc8084b41b3e291f99082ee085b307..bdd30190a5b97d073668dcd77924643e5361f825 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/long_double.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/long_double.pass.cpp
@@ -40,7 +40,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::istream is((std::streambuf*)0);
@@ -75,4 +75,6 @@ int main()
         assert(!is.eof());
         assert(!is.fail());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/long_long.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/long_long.pass.cpp
index 6529ad333f593cba46def4404fb6be0efbe4a705..1612468f4d76e6f4b52146df8d79bdf8c0916ff1 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/long_long.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/long_long.pass.cpp
@@ -40,7 +40,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::istream is((std::streambuf*)0);
@@ -75,4 +75,6 @@ int main()
         assert(!is.eof());
         assert(!is.fail());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/pointer.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/pointer.pass.cpp
index 3c8a0783fa448e9d40b991b838340c8dff75171b..0893d8cdec2b18ecef817279949d685ccbd6c097 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/pointer.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/pointer.pass.cpp
@@ -44,7 +44,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::istream is((std::streambuf*)0);
@@ -97,4 +97,6 @@ int main()
         assert( is.eof());
         assert(!is.fail());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/short.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/short.pass.cpp
index bc28ec29ba94274933e623f439f14a6a5eed382c..a0d96c3983fe6d2c9f24c992c24252ddf4232d52 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/short.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/short.pass.cpp
@@ -41,7 +41,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::istream is((std::streambuf*)0);
@@ -76,4 +76,6 @@ int main()
         assert(!is.eof());
         assert( is.fail());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/unsigned_int.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/unsigned_int.pass.cpp
index 8bbb636e6e8d9c79262b16fcd458422d43f592e2..578cfcf0cc4e018ba0dba42f182f75cc987c8e29 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/unsigned_int.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/unsigned_int.pass.cpp
@@ -40,7 +40,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::istream is((std::streambuf*)0);
@@ -75,4 +75,6 @@ int main()
         assert(!is.eof());
         assert(!is.fail());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/unsigned_long.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/unsigned_long.pass.cpp
index 5635339a816c80e40768ed66988db888985b3a8d..f1c150d79200c09693c92fe210e62c783b19a989 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/unsigned_long.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/unsigned_long.pass.cpp
@@ -40,7 +40,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::istream is((std::streambuf*)0);
@@ -75,4 +75,6 @@ int main()
         assert(!is.eof());
         assert(!is.fail());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/unsigned_long_long.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/unsigned_long_long.pass.cpp
index 402d3eab0adec09462c690655f4ec39491535fc5..068d31ac8fb66852f7a9aabf917817772fbc2063 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/unsigned_long_long.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/unsigned_long_long.pass.cpp
@@ -40,7 +40,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::istream is((std::streambuf*)0);
@@ -75,4 +75,6 @@ int main()
         assert(!is.eof());
         assert(!is.fail());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/unsigned_short.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/unsigned_short.pass.cpp
index cedd6a6c8af8516e07a274aefe3f5c79d49b281e..9906bbeac8d77ee6a33f89a8a1d27fda017a0afd 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/unsigned_short.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.arithmetic/unsigned_short.pass.cpp
@@ -40,7 +40,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::istream is((std::streambuf*)0);
@@ -75,4 +75,6 @@ int main()
         assert(!is.eof());
         assert(!is.fail());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.reqmts/tested_elsewhere.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.reqmts/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.reqmts/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream.formatted.reqmts/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/basic_ios.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/basic_ios.pass.cpp
index fadc70943dbc96e6ebee5ab627cde746c654ffa8..704c4997d5290cf2a0f08c9646036dfdb18875b8 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/basic_ios.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/basic_ios.pass.cpp
@@ -27,11 +27,13 @@ f(std::basic_ios<CharT>& is)
     return is;
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::istream is((std::streambuf*)0);
         is >> f;
         assert(f_called == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/chart.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/chart.pass.cpp
index 51e0aab1a42688802a07cec2904ec34294199fa4..cbb606cdcffac7dd71a556191f5b15f4fb9bd9e4 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/chart.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/chart.pass.cpp
@@ -38,7 +38,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb("          ");
@@ -83,4 +83,6 @@ int main()
         assert(!is.fail());
         assert(c == L'c');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/ios_base.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/ios_base.pass.cpp
index 31023cca89f8eed70a72bc94707ab919fe82cf88..ec25dc5a7e0e7fe3a72d077e8cc6daddd76bef36 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/ios_base.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/ios_base.pass.cpp
@@ -25,11 +25,13 @@ f(std::ios_base& is)
     return is;
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::istream is((std::streambuf*)0);
         is >> f;
         assert(f_called == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/istream.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/istream.pass.cpp
index 36ea25dafc8bfc1d288ff14fada86cf565c6b138..f3829c25ac4658ccd5285043727d9e1e28a6ffea 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/istream.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/istream.pass.cpp
@@ -27,11 +27,13 @@ f(std::basic_istream<CharT>& is)
     return is;
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::istream is((std::streambuf*)0);
         is >> f;
         assert(f_called == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/signed_char.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/signed_char.pass.cpp
index 293cd8b459ad282c1e2566ab2c40e5ddf57acb30..bd06de6a07bd698b8a6fa584904e57492216df09 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/signed_char.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/signed_char.pass.cpp
@@ -38,7 +38,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb("          ");
@@ -66,4 +66,6 @@ int main()
         assert(!is.fail());
         assert(c == 'c');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/signed_char_pointer.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/signed_char_pointer.pass.cpp
index 55db22bce7e070e1140eb02062895fd65db2d19d..d5128339a717f74cb4cfcefda1f0eded4266d522 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/signed_char_pointer.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/signed_char_pointer.pass.cpp
@@ -38,7 +38,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb("   abcdefghijk    ");
@@ -103,4 +103,6 @@ int main()
         assert(std::string((char*)s) == "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/streambuf.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/streambuf.pass.cpp
index dbc6e2398dfe04f4e69d470d59d6ef54bf39d918..9feb826906fe4f244b92a86bea636bcc20e938aa 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/streambuf.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/streambuf.pass.cpp
@@ -55,7 +55,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb("testing...");
@@ -65,4 +65,6 @@ int main()
         assert(sb2.str() == "testing...");
         assert(is.gcount() == 10);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/unsigned_char.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/unsigned_char.pass.cpp
index 17aff9fd8de74d0962cd32fa18d7fe3afee66066..3eceaaeb63f334f7702424da2ff8f7fd763167c2 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/unsigned_char.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/unsigned_char.pass.cpp
@@ -38,7 +38,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb("          ");
@@ -66,4 +66,6 @@ int main()
         assert(!is.fail());
         assert(c == 'c');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/unsigned_char_pointer.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/unsigned_char_pointer.pass.cpp
index 1873d70fbb2be7565a92b691cfbf4a7833a5b105..14b2993148d36092c0ebb6db7612337231885e33 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/unsigned_char_pointer.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/unsigned_char_pointer.pass.cpp
@@ -38,7 +38,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb("   abcdefghijk    ");
@@ -103,4 +103,6 @@ int main()
         assert(std::string((char*)s) == "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/wchar_t_pointer.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/wchar_t_pointer.pass.cpp
index cc06149b36e3ff37f366385ff725f34b2c4db693..f0a9e0710fba9e2e9dfe11ea3023369053fe9313 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/wchar_t_pointer.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/istream_extractors/wchar_t_pointer.pass.cpp
@@ -38,7 +38,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb("   abcdefghijk    ");
@@ -114,4 +114,6 @@ int main()
         assert(std::string(s) == "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/nothing_to_do.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.formatted/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.manip/ws.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.manip/ws.pass.cpp
index a1ab81a955329db680ce7c3efc536826cad367e7..6786ebf4ca0b42918efeb62c80bf3d22cd3c9e51 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.manip/ws.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.manip/ws.pass.cpp
@@ -39,7 +39,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb("   123");
@@ -75,4 +75,6 @@ int main()
         assert(is.eof());
         assert(is.fail());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.rvalue/rvalue.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.rvalue/rvalue.pass.cpp
index cd46b14fddee0c34641fdcfac8007d64663b38ee..8d0af7347031ff98ac3394693cf531e1aefc2679 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.rvalue/rvalue.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.rvalue/rvalue.pass.cpp
@@ -47,7 +47,7 @@ struct A{};
 bool called = false;
 void operator>>(std::istream&, A&&){ called = true; }
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb("   123");
@@ -68,4 +68,6 @@ int main()
         assert(&out == &ss);
         assert(called);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/get.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/get.pass.cpp
index b73a2fe72d86b8a58bd28d8d67f8f1d276561247..40a041741334823d187cabfc130337070fc22fd4 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/get.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/get.pass.cpp
@@ -37,7 +37,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb("          ");
@@ -96,4 +96,6 @@ int main()
         assert(c == L'c');
         assert(is.gcount() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/get_chart.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/get_chart.pass.cpp
index 86189b260492049ca54920492ad0fbef21de346e..ae31c9be06d568d4608649549a83df4687864f1a 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/get_chart.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/get_chart.pass.cpp
@@ -37,7 +37,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb("          ");
@@ -99,4 +99,6 @@ int main()
         assert(c == L'c');
         assert(is.gcount() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/get_pointer_size.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/get_pointer_size.pass.cpp
index ca2827aa0bd71750024f3a6762e92dae7d419471..149392cae3f11120192ef510045baca632fc138e 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/get_pointer_size.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/get_pointer_size.pass.cpp
@@ -48,7 +48,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb("  \n    \n ");
@@ -158,4 +158,6 @@ int main()
         assert(is.gcount() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/get_pointer_size_chart.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/get_pointer_size_chart.pass.cpp
index efaf168d6d6d3ff00a50ffa9f2e8ea3501a0820d..e7c96d6a266c54408da9f154163f2fd11e7c5639 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/get_pointer_size_chart.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/get_pointer_size_chart.pass.cpp
@@ -48,7 +48,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb("  *    * ");
@@ -158,4 +158,6 @@ int main()
         assert(is.gcount() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/get_streambuf.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/get_streambuf.pass.cpp
index 35495ef953b6cc477f81da179244977d0827a930..dda59d7ff50a915baf0461e58adaea6b17f4592c 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/get_streambuf.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/get_streambuf.pass.cpp
@@ -52,7 +52,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb("testing\n...");
@@ -84,4 +84,6 @@ int main()
         assert(!is.fail());
         assert(is.gcount() == 3);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/get_streambuf_chart.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/get_streambuf_chart.pass.cpp
index 514cd2e7f6c429d7f8177404cb9f5f41c541c76a..a1e46c2336c98177a59bbaa3876d98212f3e7e33 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/get_streambuf_chart.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/get_streambuf_chart.pass.cpp
@@ -53,7 +53,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb("testing*...");
@@ -85,4 +85,6 @@ int main()
         assert(!is.fail());
         assert(is.gcount() == 3);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/getline_pointer_size.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/getline_pointer_size.pass.cpp
index 5fa822cd1876b9fce0bafd5cd942e680678e2d39..9c91053ebdbb3666c9ad90c18c3d0b948d964664 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/getline_pointer_size.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/getline_pointer_size.pass.cpp
@@ -48,7 +48,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb("  \n    \n ");
@@ -142,4 +142,6 @@ int main()
         assert(is.gcount() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/getline_pointer_size_chart.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/getline_pointer_size_chart.pass.cpp
index 1cd19c0e1dd008dd841645dcedf626e0ce5ccd58..bee1976e95e1651dcc8210d1f4ac5974ed826379 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/getline_pointer_size_chart.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/getline_pointer_size_chart.pass.cpp
@@ -48,7 +48,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb("  *    * ");
@@ -142,4 +142,6 @@ int main()
         assert(is.gcount() == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/ignore.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/ignore.pass.cpp
index 99f35aac407a35efde5ca458b4ea6384a7670009..7f6348b01a40f56a4fafbcfb05f3c4a14c1d7c15 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/ignore.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/ignore.pass.cpp
@@ -38,7 +38,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb(" 1\n2345\n6");
@@ -72,4 +72,6 @@ int main()
         assert(!is.fail());
         assert(is.gcount() == 6);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/ignore_0xff.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/ignore_0xff.pass.cpp
index f2f895d9ce6d8fd057c6c58cde8d6c5e6338c64b..acf90e560861b22a2a340e2e62533c60795e13ba 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/ignore_0xff.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/ignore_0xff.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int bad=-1;
     std::ostringstream os;
@@ -30,4 +30,6 @@ int main()
     is.ignore(ignoreLen);
     std::istringstream::pos_type b=is.tellg();
     assert((b-a)==ignoreLen);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/peek.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/peek.pass.cpp
index 99b2b69341bf292d2a89d504816b208f20136b7e..17943463e90f9bcb0951735553e84a34b8a08304 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/peek.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/peek.pass.cpp
@@ -37,7 +37,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb(" 1\n2345\n6");
@@ -65,4 +65,6 @@ int main()
         assert(!is.fail());
         assert(is.gcount() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/putback.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/putback.pass.cpp
index 2088e4d14cb88b9f433fc5f6ac7a6b4a236c7f17..4ca3a8c0edb4e68d3e9ad0e0ada322072e260aff 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/putback.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/putback.pass.cpp
@@ -37,7 +37,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb(" 123456789");
@@ -85,4 +85,6 @@ int main()
         assert(is.bad());
         assert(is.gcount() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/read.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/read.pass.cpp
index 962aa8c0386f18e7e736214889fec8105671cdc9..9296e0bfb2e227f866549228ee6bcc34dc3599f9 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/read.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/read.pass.cpp
@@ -37,7 +37,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb(" 123456789");
@@ -77,4 +77,6 @@ int main()
         assert( is.fail());
         assert(is.gcount() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/readsome.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/readsome.pass.cpp
index 5cfd028cc620086d0f9d0aadedc6fdeebe15fe02..f99752cc1a524ead3dad9d7c1718690b63b2ae6f 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/readsome.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/readsome.pass.cpp
@@ -37,7 +37,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb(" 1234567890");
@@ -81,4 +81,6 @@ int main()
         assert(std::wstring(s, 1) == L"0");
         assert(is.readsome(s, 5) == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/seekg.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/seekg.pass.cpp
index b5e1955a7be811fb67db7471dc1e7cb5333ec2fc..c16a6397863656c429087f11668bc820b29c0800 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/seekg.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/seekg.pass.cpp
@@ -44,7 +44,7 @@ protected:
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb(" 123456789");
@@ -71,4 +71,6 @@ int main()
         assert(is.good());
         assert(!is.eof());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/seekg_off.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/seekg_off.pass.cpp
index d7607b62e9d9a5a02a10a4068d8f0d3ab5c613fc..93a7f1912d963e4368ff8a91c311a002d0d29fdd 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/seekg_off.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/seekg_off.pass.cpp
@@ -52,7 +52,7 @@ protected:
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb(" 123456789");
@@ -83,4 +83,6 @@ int main()
         assert(is.good());
         assert(!is.eof());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/sync.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/sync.pass.cpp
index 10bc991aa0f590f535944b05e47ef25f76375ebc..43ddd811080d9ba884f4492f620b4636f0b40710 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/sync.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/sync.pass.cpp
@@ -46,7 +46,7 @@ protected:
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb(" 123456789");
@@ -60,4 +60,6 @@ int main()
         assert(is.sync() == 0);
         assert(sync_called == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/tellg.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/tellg.pass.cpp
index 7f87cada9ac4732259471f9fd1ed05528c64d1de..918685b8693ee80f38ace67679f06e5c8c3dedca 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/tellg.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/tellg.pass.cpp
@@ -47,7 +47,7 @@ protected:
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb(" 123456789");
@@ -59,4 +59,6 @@ int main()
         std::wistream is(&sb);
         assert(is.tellg() == 5);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/unget.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/unget.pass.cpp
index c982f79cb9663a413ceb913ffa6833a722eaab1b..ca00af4e3c3f1ac0b7365b441cac045f3a7c1970 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/unget.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/unget.pass.cpp
@@ -37,7 +37,7 @@ public:
     CharT* egptr() const {return base::egptr();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb(" 123456789");
@@ -77,4 +77,6 @@ int main()
         assert(is.bad());
         assert(is.gcount() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream/istream.assign/member_swap.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream/istream.assign/member_swap.pass.cpp
index 8e8b16600df504cdb7239f1dbd1f9c4051ad5514..dbb2bb69e3687b85df3f2de7b320b000dbe56ec9 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream/istream.assign/member_swap.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream/istream.assign/member_swap.pass.cpp
@@ -33,7 +33,7 @@ struct test_istream
     void swap(test_istream& s) {base::swap(s);}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb1;
@@ -81,4 +81,6 @@ int main()
         assert(is2.precision() == 6);
         assert(is2.getloc().name() == "C");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream/istream.assign/move_assign.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream/istream.assign/move_assign.pass.cpp
index cc418fd4f13519eba6a3599442ef73751406038a..455edbf72ac442c0b49a80bb483ece558c072ef4 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream/istream.assign/move_assign.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream/istream.assign/move_assign.pass.cpp
@@ -38,7 +38,7 @@ struct test_istream
 };
 
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb1;
@@ -86,4 +86,6 @@ int main()
         assert(is2.precision() == 6);
         assert(is2.getloc().name() == "C");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream/istream.cons/copy.fail.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream/istream.cons/copy.fail.cpp
index c26ad292ba834ffc752d475b1002d7fa07ab76b2..017cc67a1d5e40227ab4973af99f0742858d7485 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream/istream.cons/copy.fail.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream/istream.cons/copy.fail.cpp
@@ -48,7 +48,9 @@ struct test_istream
 };
 
 
-int main()
+int main(int, char**)
 {
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream/istream.cons/move.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream/istream.cons/move.pass.cpp
index 7bf3d6619b09ce72a989284c2949b579e4f46133..4830d04d48c772408e79bb5f704ea6960fe66b2b 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream/istream.cons/move.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream/istream.cons/move.pass.cpp
@@ -36,7 +36,7 @@ struct test_istream
         : base(std::move(s)) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb;
@@ -70,4 +70,6 @@ int main()
         assert(is.precision() == 6);
         assert(is.getloc().name() == "C");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream/istream.cons/streambuf.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream/istream.cons/streambuf.pass.cpp
index 71008f7d096075c691e39a51a424f0de8ba9e340..339489dfb5e6d66386204e357ba2416784265b77 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream/istream.cons/streambuf.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream/istream.cons/streambuf.pass.cpp
@@ -23,7 +23,7 @@ struct testbuf
     testbuf() {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb;
@@ -51,4 +51,6 @@ int main()
         assert(is.getloc().name() == "C");
         assert(is.gcount() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream/istream_sentry/ctor.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream/istream_sentry/ctor.pass.cpp
index 29fed345a54b4bc89601b429525a8212af6bfaa9..fdebd66fb76ea8119ec9a0334710f9d90b9c9744 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream/istream_sentry/ctor.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream/istream_sentry/ctor.pass.cpp
@@ -49,7 +49,7 @@ protected:
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::istream is((testbuf<char>*)0);
@@ -124,4 +124,6 @@ int main()
         assert(sync_called == 0);
         assert(sb.gptr() == sb.eback());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/input.streams/istream/types.pass.cpp b/libcxx/test/std/input.output/iostream.format/input.streams/istream/types.pass.cpp
index 07e2f5558febf8881ffa7db73846cc3d571e7ff3..a5362d94b8cb7d8d7cade1fb0622799a34b21d96 100644
--- a/libcxx/test/std/input.output/iostream.format/input.streams/istream/types.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/input.streams/istream/types.pass.cpp
@@ -23,7 +23,7 @@
 #include <istream>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::basic_ios<char>, std::basic_istream<char> >::value), "");
     static_assert((std::is_same<std::basic_istream<char>::char_type, char>::value), "");
@@ -31,4 +31,6 @@ int main()
     static_assert((std::is_same<std::basic_istream<char>::int_type, std::char_traits<char>::int_type>::value), "");
     static_assert((std::is_same<std::basic_istream<char>::pos_type, std::char_traits<char>::pos_type>::value), "");
     static_assert((std::is_same<std::basic_istream<char>::off_type, std::char_traits<char>::off_type>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/nothing_to_do.pass.cpp b/libcxx/test/std/input.output/iostream.format/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/input.output/iostream.format/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.assign/member_swap.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.assign/member_swap.pass.cpp
index f322a8145bd8f03372667c66f7f584e2c4aa5cce..433d78ead195db35b34c9255c68adc8f53d3076a 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.assign/member_swap.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.assign/member_swap.pass.cpp
@@ -33,7 +33,7 @@ struct test_ostream
     void swap(test_ostream& s) {base::swap(s);}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb1;
@@ -81,4 +81,6 @@ int main()
         assert(os2.precision() == 6);
         assert(os2.getloc().name() == "C");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.assign/move_assign.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.assign/move_assign.pass.cpp
index a121cd8a5b9bf1fbdbe93f7c5c5061e091e75f00..4241b02a36d7a3328626bd9e23975687f801c63b 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.assign/move_assign.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.assign/move_assign.pass.cpp
@@ -38,7 +38,7 @@ struct test_ostream
 };
 
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb1;
@@ -86,4 +86,6 @@ int main()
         assert(os2.precision() == 6);
         assert(os2.getloc().name() == "C");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.cons/move.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.cons/move.pass.cpp
index 155889de7177db1af365db178cf57884edf6d2fa..811b7fa85664e0373ed229cd28e62e25a31b4701 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.cons/move.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.cons/move.pass.cpp
@@ -38,7 +38,7 @@ struct test_ostream
 };
 
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb;
@@ -68,4 +68,6 @@ int main()
         assert(os.precision() == 6);
         assert(os.getloc().name() == "C");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.cons/streambuf.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.cons/streambuf.pass.cpp
index ea4542be29ec0efb0b364fb9252f14443044394c..78a3a53c74e10417f3a18a296ee504a03b95350f 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.cons/streambuf.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.cons/streambuf.pass.cpp
@@ -23,7 +23,7 @@ struct testbuf
     testbuf() {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb;
@@ -49,4 +49,6 @@ int main()
         assert(os.precision() == 6);
         assert(os.getloc().name() == "C");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/nothing_to_do.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.formatted.reqmts/tested_elsewhere.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.formatted.reqmts/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.formatted.reqmts/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.formatted.reqmts/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/bool.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/bool.pass.cpp
index e472c62660d4f95282f3972fa49d5c3f03c69f8b..a0622b36567556bde23f224d79688ad8ba11b040 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/bool.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/bool.pass.cpp
@@ -48,7 +48,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::ostream os((std::streambuf*)0);
@@ -87,4 +87,6 @@ int main()
         os << b;
         assert(sb.str() == "false");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/double.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/double.pass.cpp
index f18d9361ac424bf24f6f94a10ef20acf037fa7df..2c83723cbfa00cf117ea5ca4848fd61d8a634b56 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/double.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/double.pass.cpp
@@ -48,7 +48,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::ostream os((std::streambuf*)0);
@@ -79,4 +79,6 @@ int main()
         os << n;
         assert(sb.str() == "-10.5");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/float.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/float.pass.cpp
index 041195d0e368aa0b28335653d89a98241bc3b1e2..851086abe4272188a399b83d5641cc70931e4ff7 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/float.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/float.pass.cpp
@@ -48,7 +48,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::ostream os((std::streambuf*)0);
@@ -79,4 +79,6 @@ int main()
         os << n;
         assert(sb.str() == "-10.5");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/int.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/int.pass.cpp
index 4657c98f9c93b5aade5b45e4ea76f4405c48cd6b..7dae78f9def6dba40b6d541a9ecdc46c2d89e1e1 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/int.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/int.pass.cpp
@@ -48,7 +48,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::ostream os((std::streambuf*)0);
@@ -79,4 +79,6 @@ int main()
         os << n;
         assert(sb.str() == "fffffff6");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/long.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/long.pass.cpp
index cf0184997b8b088332004a2e5196fae28a93a7c9..8f2ec631c03f9b9df1759973d8456daa4e2905fc 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/long.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/long.pass.cpp
@@ -48,7 +48,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::ostream os((std::streambuf*)0);
@@ -79,4 +79,6 @@ int main()
         os << n;
         assert(sb.str() == "fffffff6");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/long_double.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/long_double.pass.cpp
index cedef612149be578ac52e0d187a2ea39a2c9055b..b0c9950bd7ad5a0b3c592b00b8497b57edf9d406 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/long_double.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/long_double.pass.cpp
@@ -48,7 +48,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::ostream os((std::streambuf*)0);
@@ -79,4 +79,6 @@ int main()
         os << n;
         assert(sb.str() == "-10.5");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/long_long.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/long_long.pass.cpp
index 20b23b80bec931eb8cf9aa6fbca758a2bdcd1184..d87096f7213db045e9b1ba53050aedee4ea9c932 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/long_long.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/long_long.pass.cpp
@@ -48,7 +48,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::ostream os((std::streambuf*)0);
@@ -79,4 +79,6 @@ int main()
         os << n;
         assert(sb.str() == "fffffffffffffff6");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/minmax_showbase.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/minmax_showbase.pass.cpp
index c101b3cfc99834a79560ff2532ea301b7c3dc558..6db1b55cca7a17a60941db9856bd717e5606757f 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/minmax_showbase.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/minmax_showbase.pass.cpp
@@ -45,7 +45,7 @@ static void test(std::ios_base::fmtflags fmt, const char *expected)
     assert(ss.str() == expected);
 }
 
-int main()
+int main(int, char**)
 {
     const std::ios_base::fmtflags o = std::ios_base::oct;
     const std::ios_base::fmtflags d = std::ios_base::dec;
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/minus1.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/minus1.pass.cpp
index 7d51a4ddd0441217f5a0f1d358297ea4805ef2a8..c2b188a15f967d3b8434adefa7c494b35e42d10b 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/minus1.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/minus1.pass.cpp
@@ -58,7 +58,7 @@ void test_hex(const char *expected)
     assert(str == expected);
 }
 
-int main()
+int main(int, char**)
 {
 
     test_octal<uint16_t>(                "177777");
@@ -110,4 +110,6 @@ int main()
         test_hex<unsigned long long>("FFFFFFFFFFFFFFFF");
         test_hex<         long long>("FFFFFFFFFFFFFFFF");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/pointer.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/pointer.pass.cpp
index 837efd6f38a526bd87af8758ef42d6455c3642b3..f400f33544bc558fd1adcb2ea0b9aacd6d3ee398 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/pointer.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/pointer.pass.cpp
@@ -48,7 +48,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::ostream os((std::streambuf*)0);
@@ -87,4 +87,6 @@ int main()
         os << n;
         assert(os.good());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/short.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/short.pass.cpp
index 8e022edad01c19afed6d7a3a2c568d0881e13184..c45d5797b5ecef8ca517ce33308c82770e067881 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/short.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/short.pass.cpp
@@ -48,7 +48,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::ostream os((std::streambuf*)0);
@@ -79,4 +79,6 @@ int main()
         os << n;
         assert(sb.str() == "fff6");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/unsigned_int.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/unsigned_int.pass.cpp
index 2d6b0be0274b94ba4c48ac3614bb88fbb1db50bd..c24381923d1ac39e999d12890b459c50a3fd9b1c 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/unsigned_int.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/unsigned_int.pass.cpp
@@ -48,7 +48,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::ostream os((std::streambuf*)0);
@@ -79,4 +79,6 @@ int main()
         os << n;
         assert(sb.str() == "fff6");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/unsigned_long.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/unsigned_long.pass.cpp
index 636c87146fe68307667faf9465cef2445699acce..03b6396430241469dbf4aa052061b097f62bc85e 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/unsigned_long.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/unsigned_long.pass.cpp
@@ -48,7 +48,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::ostream os((std::streambuf*)0);
@@ -79,4 +79,6 @@ int main()
         os << n;
         assert(sb.str() == "fffffff6");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/unsigned_long_long.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/unsigned_long_long.pass.cpp
index 44313251e100ab59aa80b7e6f5b95e60c9edbd99..3c12f148898cefd1f188c5d0e4e1c41af26e008e 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/unsigned_long_long.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/unsigned_long_long.pass.cpp
@@ -48,7 +48,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::ostream os((std::streambuf*)0);
@@ -79,4 +79,6 @@ int main()
         os << n;
         assert(sb.str() == "fffffffffffffff6");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/unsigned_short.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/unsigned_short.pass.cpp
index 16b33f3a94e25dcca2dbff4923d18558055894a8..6cc4c71a094a6591f2d7e7367bc8cbf8b0471b5c 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/unsigned_short.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.arithmetic/unsigned_short.pass.cpp
@@ -48,7 +48,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::ostream os((std::streambuf*)0);
@@ -79,4 +79,6 @@ int main()
         os << n;
         assert(sb.str() == "fff6");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/CharT.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/CharT.pass.cpp
index cb7f0d62f47e50ef88cb5146c8f260202409200f..127c0c7dc5b2b5da8471004716f7f66b408c2000 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/CharT.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/CharT.pass.cpp
@@ -49,7 +49,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::wostream os((std::wstreambuf*)0);
@@ -84,4 +84,6 @@ int main()
         assert(sb.str() == L"a    ");
         assert(os.width() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/CharT_pointer.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/CharT_pointer.pass.cpp
index a07edba5d9f2a82292c762139284f3a9b63452b7..85edde06d4fe12f254f74e47b6569a3e3fa963e5 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/CharT_pointer.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/CharT_pointer.pass.cpp
@@ -49,7 +49,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::wostream os((std::wstreambuf*)0);
@@ -84,4 +84,6 @@ int main()
         assert(sb.str() == L"123  ");
         assert(os.width() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/char.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/char.pass.cpp
index 6e926d10fb0762ca828ca01c006be9f5302e7a5e..5532a68650b9287aa4e9d74eb20a59bed5a3e6d5 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/char.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/char.pass.cpp
@@ -49,7 +49,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::ostream os((std::streambuf*)0);
@@ -84,4 +84,6 @@ int main()
         assert(sb.str() == "a    ");
         assert(os.width() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/char_pointer.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/char_pointer.pass.cpp
index 23874768fd0dd964dbdfd9441508caa5fe9a2b46..f6e2445faeb7e3b7f291bfa67cefc7a08f883b9b 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/char_pointer.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/char_pointer.pass.cpp
@@ -49,7 +49,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::ostream os((std::streambuf*)0);
@@ -84,4 +84,6 @@ int main()
         assert(sb.str() == "123  ");
         assert(os.width() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/char_to_wide.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/char_to_wide.pass.cpp
index f5647e1a9249baef4c5ed47d5d2bd13356fcda38..f12478e538418ab022fcd676328e91097e53c6a3 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/char_to_wide.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/char_to_wide.pass.cpp
@@ -49,7 +49,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::wostream os((std::wstreambuf*)0);
@@ -84,4 +84,6 @@ int main()
         assert(sb.str() == L"a    ");
         assert(os.width() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/char_to_wide_pointer.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/char_to_wide_pointer.pass.cpp
index ff4e85eb90fca13f73ff80e1f83e05120da8cb0e..1b11d8550ae2e962229477267396cc17b27f570c 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/char_to_wide_pointer.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/char_to_wide_pointer.pass.cpp
@@ -49,7 +49,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::wostream os((std::wstreambuf*)0);
@@ -84,4 +84,6 @@ int main()
         assert(sb.str() == L"123  ");
         assert(os.width() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/signed_char.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/signed_char.pass.cpp
index ab3e9b580b86be28163186398ffe356ad4af0f07..26f295ec2d0837670e339c1af78d92ce045a374e 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/signed_char.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/signed_char.pass.cpp
@@ -49,7 +49,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::ostream os((std::streambuf*)0);
@@ -84,4 +84,6 @@ int main()
         assert(sb.str() == "a    ");
         assert(os.width() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/signed_char_pointer.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/signed_char_pointer.pass.cpp
index 36b9586b81296f5de6ddebba4db1a2cc65bd9d24..83143521bc56c5d1a6b543be2d30cd9fea9f5591 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/signed_char_pointer.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/signed_char_pointer.pass.cpp
@@ -49,7 +49,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::ostream os((std::streambuf*)0);
@@ -84,4 +84,6 @@ int main()
         assert(sb.str() == "123  ");
         assert(os.width() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/unsigned_char.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/unsigned_char.pass.cpp
index 95609a2642b2f701234184b6d3638fbca12282ee..e45281f866fa4b6984c6d6833ce440a605187065 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/unsigned_char.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/unsigned_char.pass.cpp
@@ -49,7 +49,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::ostream os((std::streambuf*)0);
@@ -84,4 +84,6 @@ int main()
         assert(sb.str() == "a    ");
         assert(os.width() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/unsigned_char_pointer.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/unsigned_char_pointer.pass.cpp
index ef7e6166e9d49d318e451d533000bf9aae24b495..55b429b2dc4b26a38991f4b86ef6f25e6094bb28 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/unsigned_char_pointer.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters.character/unsigned_char_pointer.pass.cpp
@@ -49,7 +49,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::ostream os((std::streambuf*)0);
@@ -84,4 +84,6 @@ int main()
         assert(sb.str() == "123  ");
         assert(os.width() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters/basic_ios.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters/basic_ios.pass.cpp
index 1d2056250816b5b132a7b32bb26aae619fe0cbae..921311f99cee023aeb1e9445ee752cfe729cfd07 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters/basic_ios.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters/basic_ios.pass.cpp
@@ -57,7 +57,7 @@ f(std::basic_ios<CharT>& os)
     return os;
 }
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb;
@@ -66,4 +66,6 @@ int main()
         os << f;
         assert( (os.flags() & std::ios_base::uppercase));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters/ios_base.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters/ios_base.pass.cpp
index 763be3a8382ab5a20c4147eba5b9209573cd285f..b10330b7c69a56ce779cd847b03335315a2f0f76 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters/ios_base.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters/ios_base.pass.cpp
@@ -48,7 +48,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb;
@@ -57,4 +57,6 @@ int main()
         os << std::uppercase;
         assert( (os.flags() & std::ios_base::uppercase));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters/ostream.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters/ostream.pass.cpp
index ab39c28aac66d214e8df20104b0434482ecb3869..e57e5412c39cb622401632328b90252f2a537b2c 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters/ostream.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters/ostream.pass.cpp
@@ -57,7 +57,7 @@ f(std::basic_ostream<CharT>& os)
     return os;
 }
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb;
@@ -65,4 +65,6 @@ int main()
         os << f;
         assert(sb.str() == "testing...");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters/streambuf.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters/streambuf.pass.cpp
index 5668185b0cf2927ca8873c1af8f0e65a060b3c9d..d2935ca734a1aa5fc552cf360395df728e2179f2 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters/streambuf.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters/streambuf.pass.cpp
@@ -55,7 +55,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb;
@@ -65,4 +65,6 @@ int main()
         os << &sb2;
         assert(sb.str() == "testing...");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.manip/endl.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.manip/endl.pass.cpp
index c6a7d92180c2a4c4aa25e264f757b2eb78a8b4fe..03cd411294b53e7209fc0bcc6080edcb9c4d1970 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.manip/endl.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.manip/endl.pass.cpp
@@ -58,7 +58,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb;
@@ -76,4 +76,6 @@ int main()
         assert(sync_called == 2);
         assert(os.good());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.manip/ends.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.manip/ends.pass.cpp
index 20703864bbe4db38402271fb920163ab6fe846ac..5f18aecf907f573834eef9d09c51340baf69fb44 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.manip/ends.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.manip/ends.pass.cpp
@@ -49,7 +49,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb;
@@ -67,4 +67,6 @@ int main()
         assert(sb.str().back() == 0);
         assert(os.good());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.manip/flush.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.manip/flush.pass.cpp
index 8ad82cb3a30623b5e69636500cc3b14604cdb357..666a92532f8ab8d3a39e2113ed89e60133f89491 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.manip/flush.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.manip/flush.pass.cpp
@@ -38,7 +38,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb;
@@ -54,4 +54,6 @@ int main()
         assert(sync_called == 2);
         assert(os.good());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.rvalue/CharT_pointer.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.rvalue/CharT_pointer.pass.cpp
index 7b7890abdddc02c5d30eae94a9c6d6e60d26799e..724593f1acda8433be165ced86cab085783e6609 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.rvalue/CharT_pointer.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.rvalue/CharT_pointer.pass.cpp
@@ -54,7 +54,7 @@ protected:
 };
 
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb;
@@ -66,4 +66,6 @@ int main()
         std::wostream(&sb) << L"123";
         assert(sb.str() == L"123");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.seeks/seekp.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.seeks/seekp.pass.cpp
index f48ed92b8b6abfda60da539acc3752a98495bcbb..7be006f1060f0e1df41f82417460b48478d088cf 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.seeks/seekp.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.seeks/seekp.pass.cpp
@@ -36,7 +36,7 @@ protected:
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         seekpos_called = 0;
@@ -64,4 +64,6 @@ int main()
         assert(seekpos_called == 1);
         assert(os.rdstate() == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.seeks/seekp2.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.seeks/seekp2.pass.cpp
index 130528046e3fb63dc860f53d1c1dd95a311e6738..dc8e5ed5cd3ad6a85f556ee1b3442e5fc9196ee8 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.seeks/seekp2.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.seeks/seekp2.pass.cpp
@@ -38,7 +38,7 @@ protected:
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         seekoff_called = 0;
@@ -66,4 +66,6 @@ int main()
         assert(seekoff_called == 1);
         assert(os.rdstate() == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.seeks/tellp.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.seeks/tellp.pass.cpp
index a93032b20be92106e8b9eaf226edf636549ff6f0..d9361e83978e22615a7a679b27ad961d8a26789e 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.seeks/tellp.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.seeks/tellp.pass.cpp
@@ -38,7 +38,7 @@ protected:
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::ostream os((std::streambuf*)0);
@@ -50,4 +50,6 @@ int main()
         assert(os.tellp() == 10);
         assert(seekoff_called == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.unformatted/flush.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.unformatted/flush.pass.cpp
index f07af7471bf5535d59c5aebb3a765f9fc7a31451..15a3b59ea0a378526ff395d49cc34b564520e892 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.unformatted/flush.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.unformatted/flush.pass.cpp
@@ -38,7 +38,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb;
@@ -50,4 +50,6 @@ int main()
         assert(os.bad());
         assert(sync_called == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.unformatted/put.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.unformatted/put.pass.cpp
index 4dc25175130ed93d771d0aff2847c08daed54b9f..79f7d9f9fb8b018110ae2b3e741bd88093cd76ae 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.unformatted/put.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.unformatted/put.pass.cpp
@@ -48,7 +48,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::wostream os((std::wstreambuf*)0);
@@ -72,4 +72,6 @@ int main()
         assert(sb.str() == "a");
         assert(os.good());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.unformatted/write.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.unformatted/write.pass.cpp
index 4b804a501ff656b476c9fbcd7799e89c21def404..9ebfdf54b5087df53f77954ff7b421bba61e539c 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream.unformatted/write.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream.unformatted/write.pass.cpp
@@ -48,7 +48,7 @@ protected:
         }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::wostream os((std::wstreambuf*)0);
@@ -72,4 +72,6 @@ int main()
         assert(sb.str() == s);
         assert(os.good());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream/types.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream/types.pass.cpp
index dbdb52ee749a6cc0c70a1d49ba799e454d9fd828..e0e9cddde410a293d113bba92a720225d881cc17 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream/types.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream/types.pass.cpp
@@ -23,7 +23,7 @@
 #include <ostream>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::basic_ios<char>, std::basic_ostream<char> >::value), "");
     static_assert((std::is_same<std::basic_ostream<char>::char_type, char>::value), "");
@@ -31,4 +31,6 @@ int main()
     static_assert((std::is_same<std::basic_ostream<char>::int_type, std::char_traits<char>::int_type>::value), "");
     static_assert((std::is_same<std::basic_ostream<char>::pos_type, std::char_traits<char>::pos_type>::value), "");
     static_assert((std::is_same<std::basic_ostream<char>::off_type, std::char_traits<char>::off_type>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream_sentry/construct.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream_sentry/construct.pass.cpp
index f7d78537eb7c79cbef2a6562d47a850247a921f0..c21776a9aa4ed7a96d5f7c73044de5a8a5309f4e 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream_sentry/construct.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream_sentry/construct.pass.cpp
@@ -33,7 +33,7 @@ protected:
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::ostream os((std::streambuf*)0);
@@ -57,4 +57,6 @@ int main()
         assert(bool(s));
         assert(sync_called == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/output.streams/ostream_sentry/destruct.pass.cpp b/libcxx/test/std/input.output/iostream.format/output.streams/ostream_sentry/destruct.pass.cpp
index ab67442d7b6c5b965bb7e81e621ce08628f60639..66ed0acba266f68430c7cc34393d4813f1db65cc 100644
--- a/libcxx/test/std/input.output/iostream.format/output.streams/ostream_sentry/destruct.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/output.streams/ostream_sentry/destruct.pass.cpp
@@ -35,7 +35,7 @@ protected:
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::ostream os((std::streambuf*)0);
@@ -75,4 +75,6 @@ int main()
         assert(sync_called == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/quoted.manip/quoted.pass.cpp b/libcxx/test/std/input.output/iostream.format/quoted.manip/quoted.pass.cpp
index c39c0808716e090c80c8c84a37f480577d688528..1e54e5657efd116d48da9ee42a4e0c66804b2f02 100644
--- a/libcxx/test/std/input.output/iostream.format/quoted.manip/quoted.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/quoted.manip/quoted.pass.cpp
@@ -123,7 +123,7 @@ void test_padding () {
 }
 
 
-int main()
+int main(int, char**)
 {
     both_ways ( "" );   // This is a compilation check
 
@@ -173,8 +173,12 @@ int main()
     assert ( unquote (  "" ) ==  "" ); // nothing there
     assert ( unquote ( L"" ) == L"" ); // nothing there
     test_padding ();
-    }
+    
+    return 0;
+}
 
 #else
-int main() {}
+int main(int, char**) {
+  return 0;
+}
 #endif
diff --git a/libcxx/test/std/input.output/iostream.format/quoted.manip/quoted_char.fail.cpp b/libcxx/test/std/input.output/iostream.format/quoted.manip/quoted_char.fail.cpp
index d7b33cdf2309845d6c4d40f7b0c17384130e7110..4b343013e2583db3165d3daa778d9148c6306fa7 100644
--- a/libcxx/test/std/input.output/iostream.format/quoted.manip/quoted_char.fail.cpp
+++ b/libcxx/test/std/input.output/iostream.format/quoted.manip/quoted_char.fail.cpp
@@ -30,7 +30,7 @@ void round_trip ( const char *p ) {
 
 
 
-int main()
+int main(int, char**)
 {
     round_trip ( "Hi Mom" );
 }
diff --git a/libcxx/test/std/input.output/iostream.format/quoted.manip/quoted_traits.fail.cpp b/libcxx/test/std/input.output/iostream.format/quoted.manip/quoted_traits.fail.cpp
index 257826b7dbf1484288e1ddb486cc339d114f9b77..b19eea376d825b50a0706136d3029fc2394306cb 100644
--- a/libcxx/test/std/input.output/iostream.format/quoted.manip/quoted_traits.fail.cpp
+++ b/libcxx/test/std/input.output/iostream.format/quoted.manip/quoted_traits.fail.cpp
@@ -36,7 +36,7 @@ void round_trip ( const char *p ) {
 
 
 
-int main()
+int main(int, char**)
 {
     round_trip ( "Hi Mom" );
 }
diff --git a/libcxx/test/std/input.output/iostream.format/std.manip/resetiosflags.pass.cpp b/libcxx/test/std/input.output/iostream.format/std.manip/resetiosflags.pass.cpp
index 82ef40c9a12ba03cb75b9644f16efc980423c648..637aa4ee317e55101d292cee7e7f0b4d97eca14e 100644
--- a/libcxx/test/std/input.output/iostream.format/std.manip/resetiosflags.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/std.manip/resetiosflags.pass.cpp
@@ -22,7 +22,7 @@ struct testbuf
     testbuf() {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb;
@@ -52,4 +52,6 @@ int main()
         os << std::resetiosflags(std::ios_base::skipws);
         assert(!(os.flags() & std::ios_base::skipws));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/std.manip/setbase.pass.cpp b/libcxx/test/std/input.output/iostream.format/std.manip/setbase.pass.cpp
index 83d4960c4205e9c52b20e1a81e4e00b5430d340e..580ae4d24c3cff6a2c37d07e5b046ad05f4ddc3f 100644
--- a/libcxx/test/std/input.output/iostream.format/std.manip/setbase.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/std.manip/setbase.pass.cpp
@@ -22,7 +22,7 @@ struct testbuf
     testbuf() {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb;
@@ -72,4 +72,6 @@ int main()
         os << std::setbase(15);
         assert((os.flags() & std::ios_base::basefield) == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/std.manip/setfill.pass.cpp b/libcxx/test/std/input.output/iostream.format/std.manip/setfill.pass.cpp
index cc548b37ddd8e9adbdcbcf8909c00ce7eab2c881..4398ff61301cb128740bbbb24ee0c3f44cab125c 100644
--- a/libcxx/test/std/input.output/iostream.format/std.manip/setfill.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/std.manip/setfill.pass.cpp
@@ -21,7 +21,7 @@ struct testbuf
     testbuf() {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb;
@@ -35,4 +35,6 @@ int main()
         os << std::setfill(L'*');
         assert(os.fill() == L'*');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/std.manip/setiosflags.pass.cpp b/libcxx/test/std/input.output/iostream.format/std.manip/setiosflags.pass.cpp
index f4bf9e7f4fdaf526b262d938dbcb48dcc3c4f109..ccf605ad7adebca529ece142e56cab43d9372576 100644
--- a/libcxx/test/std/input.output/iostream.format/std.manip/setiosflags.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/std.manip/setiosflags.pass.cpp
@@ -22,7 +22,7 @@ struct testbuf
     testbuf() {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb;
@@ -52,4 +52,6 @@ int main()
         os << std::setiosflags(std::ios_base::oct);
         assert(os.flags() & std::ios_base::oct);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/std.manip/setprecision.pass.cpp b/libcxx/test/std/input.output/iostream.format/std.manip/setprecision.pass.cpp
index eef401c63e548c35b9926633ec70517ec6c2f5c6..e570faf7cb7be3c0e62b01932f0242f8ed91ac62 100644
--- a/libcxx/test/std/input.output/iostream.format/std.manip/setprecision.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/std.manip/setprecision.pass.cpp
@@ -22,7 +22,7 @@ struct testbuf
     testbuf() {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb;
@@ -48,4 +48,6 @@ int main()
         os << std::setprecision(10);
         assert(os.precision() == 10);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.format/std.manip/setw.pass.cpp b/libcxx/test/std/input.output/iostream.format/std.manip/setw.pass.cpp
index cd5e3f2b3e9d2dbc994634f99eb3daebd98bf526..44aa41e57465f4b845d02368204d4577e2a3267f 100644
--- a/libcxx/test/std/input.output/iostream.format/std.manip/setw.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.format/std.manip/setw.pass.cpp
@@ -22,7 +22,7 @@ struct testbuf
     testbuf() {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb;
@@ -48,4 +48,6 @@ int main()
         os << std::setw(10);
         assert(os.width() == 10);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.forward/iosfwd.pass.cpp b/libcxx/test/std/input.output/iostream.forward/iosfwd.pass.cpp
index 1caadd1c0992146440b711365ee564bfb468f2be..5c60dcca2869ea9341b2f3de3ea6538a605f5021 100644
--- a/libcxx/test/std/input.output/iostream.forward/iosfwd.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.forward/iosfwd.pass.cpp
@@ -17,7 +17,7 @@ template <class Ptr> void test()
     ((void)p); // Prevent unused warning
 }
 
-int main()
+int main(int, char**)
 {
     test<std::char_traits<char>*          >();
     test<std::char_traits<wchar_t>*       >();
@@ -119,4 +119,6 @@ int main()
     test<std::fpos<std::mbstate_t>*>();
     test<std::streampos*           >();
     test<std::wstreampos*          >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.objects/narrow.stream.objects/cerr.pass.cpp b/libcxx/test/std/input.output/iostream.objects/narrow.stream.objects/cerr.pass.cpp
index 1c046bcf4479dc02455065388e01e34a9a53e047..ef3cbf676aa405b7ef56644ef3c8233fce8bae1a 100644
--- a/libcxx/test/std/input.output/iostream.objects/narrow.stream.objects/cerr.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.objects/narrow.stream.objects/cerr.pass.cpp
@@ -13,7 +13,7 @@
 #include <iostream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
 #if 0
     std::cerr << "Hello World!\n";
@@ -25,4 +25,6 @@ int main()
 #endif
     assert(std::cerr.flags() & std::ios_base::unitbuf);
 #endif  // 0
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.objects/narrow.stream.objects/cin.pass.cpp b/libcxx/test/std/input.output/iostream.objects/narrow.stream.objects/cin.pass.cpp
index cce1f3eaf622fd2fab68991c1c3fd6a5f234ac15..d28255043b601bce233aa84aeb5c387415a3fd91 100644
--- a/libcxx/test/std/input.output/iostream.objects/narrow.stream.objects/cin.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.objects/narrow.stream.objects/cin.pass.cpp
@@ -15,7 +15,7 @@
 #include <iostream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
 #if 0
     std::cout << "Hello World!\n";
@@ -30,4 +30,6 @@ int main()
     assert(std::cin.tie() == &std::cout);
 #endif
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.objects/narrow.stream.objects/clog.pass.cpp b/libcxx/test/std/input.output/iostream.objects/narrow.stream.objects/clog.pass.cpp
index 49fffca4286a1c07190f8f3b8dca6ec5d4e8d091..97e67fddf81f6ea0078db60399717c2751df224c 100644
--- a/libcxx/test/std/input.output/iostream.objects/narrow.stream.objects/clog.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.objects/narrow.stream.objects/clog.pass.cpp
@@ -12,11 +12,13 @@
 
 #include <iostream>
 
-int main()
+int main(int, char**)
 {
 #if 0
     std::clog << "Hello World!\n";
 #else
     (void)std::clog;
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.objects/narrow.stream.objects/cout.pass.cpp b/libcxx/test/std/input.output/iostream.objects/narrow.stream.objects/cout.pass.cpp
index d470956e284dcc33a8565cbb8e5c246dfcec97d2..44ae085779214c1183bad66987af4b349634a58f 100644
--- a/libcxx/test/std/input.output/iostream.objects/narrow.stream.objects/cout.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.objects/narrow.stream.objects/cout.pass.cpp
@@ -14,7 +14,7 @@
 
 #include <iostream>
 
-int main()
+int main(int, char**)
 {
 #if 0
     std::cout << "Hello World!\n";
@@ -25,4 +25,6 @@ int main()
 #else  // 0
     (void)std::cout;
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.objects/wide.stream.objects/wcerr.pass.cpp b/libcxx/test/std/input.output/iostream.objects/wide.stream.objects/wcerr.pass.cpp
index 516f3b8c994a2e02636960312e2f16b759616353..0af3f5ee7e521670072afe46d377c1a900aa47d4 100644
--- a/libcxx/test/std/input.output/iostream.objects/wide.stream.objects/wcerr.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.objects/wide.stream.objects/wcerr.pass.cpp
@@ -13,7 +13,7 @@
 #include <iostream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
 #if 0
     std::wcerr << L"Hello World!\n";
@@ -25,4 +25,6 @@ int main()
 #endif
     assert(std::wcerr.flags() & std::ios_base::unitbuf);
 #endif  // 0
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.objects/wide.stream.objects/wcin.pass.cpp b/libcxx/test/std/input.output/iostream.objects/wide.stream.objects/wcin.pass.cpp
index 862f2203456e39c9feb63ca0a0057229dd4a5c15..68c1528602b8800e12801903193051fa24a31911 100644
--- a/libcxx/test/std/input.output/iostream.objects/wide.stream.objects/wcin.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.objects/wide.stream.objects/wcin.pass.cpp
@@ -15,7 +15,7 @@
 #include <iostream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
 #if 0
     std::wcout << L"Hello World!\n";
@@ -30,4 +30,6 @@ int main()
     assert(std::wcin.tie() == &std::wcout);
 #endif
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.objects/wide.stream.objects/wclog.pass.cpp b/libcxx/test/std/input.output/iostream.objects/wide.stream.objects/wclog.pass.cpp
index a6883b257049a102475fb79d9891113a83660559..ad7e35b5151372420d5dc433921e254fe3ebdeb5 100644
--- a/libcxx/test/std/input.output/iostream.objects/wide.stream.objects/wclog.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.objects/wide.stream.objects/wclog.pass.cpp
@@ -12,11 +12,13 @@
 
 #include <iostream>
 
-int main()
+int main(int, char**)
 {
 #if 0
     std::wclog << L"Hello World!\n";
 #else
     (void)std::wclog;
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostream.objects/wide.stream.objects/wcout.pass.cpp b/libcxx/test/std/input.output/iostream.objects/wide.stream.objects/wcout.pass.cpp
index ec5bb50ecb0b48278619ff1b482ad381f988a5ef..5703c61639d32da78609065db4cb21b25307898b 100644
--- a/libcxx/test/std/input.output/iostream.objects/wide.stream.objects/wcout.pass.cpp
+++ b/libcxx/test/std/input.output/iostream.objects/wide.stream.objects/wcout.pass.cpp
@@ -14,11 +14,13 @@
 
 #include <iostream>
 
-int main()
+int main(int, char**)
 {
 #if 0
     std::wcout << L"Hello World!\n";
 #else
     (void)std::wcout;
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/fpos/fpos.members/state.pass.cpp b/libcxx/test/std/input.output/iostreams.base/fpos/fpos.members/state.pass.cpp
index 9c4d74dcd095960662ef70e505bac988583a6c1f..3938d79804cb621c18bb338ecd861297d1a648db 100644
--- a/libcxx/test/std/input.output/iostreams.base/fpos/fpos.members/state.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/fpos/fpos.members/state.pass.cpp
@@ -15,9 +15,11 @@
 #include <ios>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::fpos<int> f;
     f.state(3);
     assert(f.state() == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/fpos/fpos.operations/addition.pass.cpp b/libcxx/test/std/input.output/iostreams.base/fpos/fpos.operations/addition.pass.cpp
index 1b58566088ca3166d6976efbbacc832340d03e55..30bdabc368c68f160952b65205bf52115ff08cb2 100644
--- a/libcxx/test/std/input.output/iostreams.base/fpos/fpos.operations/addition.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/fpos/fpos.operations/addition.pass.cpp
@@ -15,7 +15,7 @@
 #include <ios>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::fpos<std::mbstate_t> P;
     P p(5);
@@ -24,4 +24,6 @@ int main()
     assert(q == P(11));
     p += o;
     assert(p == q);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/fpos/fpos.operations/ctor_int.pass.cpp b/libcxx/test/std/input.output/iostreams.base/fpos/fpos.operations/ctor_int.pass.cpp
index ff30e81afbcee7719c8a0d3f592735055ea03108..e27c9068784d6537def6c1c47059b69ddbc31e47 100644
--- a/libcxx/test/std/input.output/iostreams.base/fpos/fpos.operations/ctor_int.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/fpos/fpos.operations/ctor_int.pass.cpp
@@ -15,9 +15,11 @@
 #include <ios>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::fpos<std::mbstate_t> P;
     P p(5);
     assert(p == P(5));
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/fpos/fpos.operations/difference.pass.cpp b/libcxx/test/std/input.output/iostreams.base/fpos/fpos.operations/difference.pass.cpp
index 405c98899fc27587e3103831aab4b57acfddd2f8..114e382a71f9b4b750ab2e41f6613204803f82cd 100644
--- a/libcxx/test/std/input.output/iostreams.base/fpos/fpos.operations/difference.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/fpos/fpos.operations/difference.pass.cpp
@@ -15,11 +15,13 @@
 #include <ios>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::fpos<std::mbstate_t> P;
     P p(11);
     P q(6);
     std::streamoff o = p - q;
     assert(o == 5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/fpos/fpos.operations/eq_int.pass.cpp b/libcxx/test/std/input.output/iostreams.base/fpos/fpos.operations/eq_int.pass.cpp
index 20ffe33c413cea4c3072791a9e175b9cc12e3092..1b1a5f33d1c6a5f7d24209a7bf41cf4a20e8dd18 100644
--- a/libcxx/test/std/input.output/iostreams.base/fpos/fpos.operations/eq_int.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/fpos/fpos.operations/eq_int.pass.cpp
@@ -15,11 +15,13 @@
 #include <ios>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::fpos<std::mbstate_t> P;
     P p(5);
     P q(6);
     assert(p == p);
     assert(p != q);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/fpos/fpos.operations/offset.pass.cpp b/libcxx/test/std/input.output/iostreams.base/fpos/fpos.operations/offset.pass.cpp
index 108cffdf90f9208e112e7c3776a592574f622765..a8e763f72454fa65744abbb5b0be20ec248f4ef8 100644
--- a/libcxx/test/std/input.output/iostreams.base/fpos/fpos.operations/offset.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/fpos/fpos.operations/offset.pass.cpp
@@ -15,10 +15,12 @@
 #include <ios>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::fpos<std::mbstate_t> P;
     P p(std::streamoff(7));
     std::streamoff offset(p);
     assert(offset == 7);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/fpos/fpos.operations/streamsize.pass.cpp b/libcxx/test/std/input.output/iostreams.base/fpos/fpos.operations/streamsize.pass.cpp
index e6cb51ae17407c080c35abf80aeca8a6f5ebe8e0..9d9cd79024e92cb3b041a1786b7bb10181ee7124 100644
--- a/libcxx/test/std/input.output/iostreams.base/fpos/fpos.operations/streamsize.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/fpos/fpos.operations/streamsize.pass.cpp
@@ -13,11 +13,13 @@
 #include <ios>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::streamoff o(5);
     std::streamsize sz(o);
     assert(sz == 5);
     std::streamoff o2(sz);
     assert(o == o2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/fpos/fpos.operations/subtraction.pass.cpp b/libcxx/test/std/input.output/iostreams.base/fpos/fpos.operations/subtraction.pass.cpp
index 9991be4f953b80e4f4c999701a22fad0bf7b5772..b38378b7e8cc8cba7b024e62395e4e6b2a0695dd 100644
--- a/libcxx/test/std/input.output/iostreams.base/fpos/fpos.operations/subtraction.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/fpos/fpos.operations/subtraction.pass.cpp
@@ -15,7 +15,7 @@
 #include <ios>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::fpos<std::mbstate_t> P;
     P p(11);
@@ -24,4 +24,6 @@ int main()
     assert(q == P(5));
     p -= o;
     assert(p == q);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/fpos/nothing_to_do.pass.cpp b/libcxx/test/std/input.output/iostreams.base/fpos/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/input.output/iostreams.base/fpos/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/fpos/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/flags.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/flags.pass.cpp
index 1a958b615b99349c2f7f826c2214b4f84a859b74..da147bd82f8b182b8d3e5b63c941f0747c25333f 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/flags.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/flags.pass.cpp
@@ -25,8 +25,10 @@ public:
     }
 };
 
-int main()
+int main(int, char**)
 {
     const test t;
     assert(t.flags() == (test::skipws | test::dec));
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/flags_fmtflags.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/flags_fmtflags.pass.cpp
index 0f49701fbf2b604c320530fea068816ae306622c..ed39a54245a5579b2ef546281060ec2e5609d35e 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/flags_fmtflags.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/flags_fmtflags.pass.cpp
@@ -25,11 +25,13 @@ public:
     }
 };
 
-int main()
+int main(int, char**)
 {
     test t;
     assert(t.flags() == (test::skipws | test::dec));
     test::fmtflags f = t.flags(test::hex | test::right);
     assert(f == (test::skipws | test::dec));
     assert(t.flags() == (test::hex | test::right));
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/precision.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/precision.pass.cpp
index d22ca2647b5719c5695ced98ca1052007eb284cd..f6387c828f25331f844e76c21aebd62a28f21a69 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/precision.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/precision.pass.cpp
@@ -25,8 +25,10 @@ public:
     }
 };
 
-int main()
+int main(int, char**)
 {
     const test t;
     assert(t.precision() == 6);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/precision_streamsize.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/precision_streamsize.pass.cpp
index ab38ab3d5e890c3442c489fbb7b82b24d366fbbf..475ddc47f8ac43b2df222c8849bd528cbb767289 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/precision_streamsize.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/precision_streamsize.pass.cpp
@@ -25,11 +25,13 @@ public:
     }
 };
 
-int main()
+int main(int, char**)
 {
     test t;
     assert(t.precision() == 6);
     std::streamsize p = t.precision(10);
     assert(p == 6);
     assert(t.precision() == 10);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/setf_fmtflags.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/setf_fmtflags.pass.cpp
index da742974dabf25a5535fd43e90e5086839fd7220..d8ca9cc8239ebefba09c1016114ca413a7e65102 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/setf_fmtflags.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/setf_fmtflags.pass.cpp
@@ -25,11 +25,13 @@ public:
     }
 };
 
-int main()
+int main(int, char**)
 {
     test t;
     assert(t.flags() == (test::skipws | test::dec));
     test::fmtflags f = t.setf(test::hex | test::right);
     assert(f == (test::skipws | test::dec));
     assert(t.flags() == (test::skipws | test::dec | test::hex | test::right));
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/setf_fmtflags_mask.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/setf_fmtflags_mask.pass.cpp
index 00ce003dada08680c061ceaa534ce9b8d994cd8f..6793ced7fe039ae10a97b7b992a77c975124ceb4 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/setf_fmtflags_mask.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/setf_fmtflags_mask.pass.cpp
@@ -25,11 +25,13 @@ public:
     }
 };
 
-int main()
+int main(int, char**)
 {
     test t;
     assert(t.flags() == (test::skipws | test::dec));
     test::fmtflags f = t.setf(test::hex | test::right, test::dec | test::right);
     assert(f == (test::skipws | test::dec));
     assert(t.flags() == (test::skipws | test::right));
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/unsetf_mask.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/unsetf_mask.pass.cpp
index 49a55cb402326932c89cdf34ba308bc6d4de844d..f20acff1347f3912dd35dcadd3e25aafdba216ca 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/unsetf_mask.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/unsetf_mask.pass.cpp
@@ -25,10 +25,12 @@ public:
     }
 };
 
-int main()
+int main(int, char**)
 {
     test t;
     assert(t.flags() == (test::skipws | test::dec));
     t.unsetf(test::dec | test::right);
     assert(t.flags() == test::skipws);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/width.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/width.pass.cpp
index d812aa291f128f92b48f271f514d15a2b964d40e..fc2601a456756f8eaa052ced72b43b3961d3bde1 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/width.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/width.pass.cpp
@@ -25,8 +25,10 @@ public:
     }
 };
 
-int main()
+int main(int, char**)
 {
     const test t;
     assert(t.width() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/width_streamsize.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/width_streamsize.pass.cpp
index 7c906094804fb0e064d3d81426f76b34af789826..3b389e5fd223f91efbd25a6f9aa7fb9ce0f00e1e 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/width_streamsize.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios.base/fmtflags.state/width_streamsize.pass.cpp
@@ -25,11 +25,13 @@ public:
     }
 };
 
-int main()
+int main(int, char**)
 {
     test t;
     assert(t.width() == 0);
     std::streamsize w = t.width(4);
     assert(w == 0);
     assert(t.width() == 4);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.base.callback/register_callback.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.base.callback/register_callback.pass.cpp
index 3de42eabc4ad8159a81bacc7ccf41b8723cfd356..316d23a528bcacdd5f084f110669cf1c4326d3b0 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.base.callback/register_callback.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.base.callback/register_callback.pass.cpp
@@ -43,7 +43,7 @@ void f1(std::ios_base::event ev, std::ios_base& stream, int index)
     }
 }
 
-int main()
+int main(int, char**)
 {
     test t;
     std::ios_base& b = t;
@@ -52,4 +52,6 @@ int main()
     b.register_callback(f1, 4);
     std::locale l = b.imbue(std::locale(LOCALE_en_US_UTF_8));
     assert(f1_called == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.base.cons/dtor.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.base.cons/dtor.pass.cpp
index 12434f5a2194471d776835e08098cce018e46916..7c78ea5667d9d858668f275efb2a5080a16640c0 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.base.cons/dtor.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.base.cons/dtor.pass.cpp
@@ -70,7 +70,7 @@ void f3(std::ios_base::event ev, std::ios_base& stream, int index)
     }
 }
 
-int main()
+int main(int, char**)
 {
     {
         test t;
@@ -82,4 +82,6 @@ int main()
     assert(f1_called);
     assert(f2_called);
     assert(f3_called);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.base.locales/getloc.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.base.locales/getloc.pass.cpp
index 821a1f51461121d6193d5f38ec49ece246ef763c..06b8d83c79ed2d3073515207fa1253af370334cc 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.base.locales/getloc.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.base.locales/getloc.pass.cpp
@@ -26,8 +26,10 @@ public:
     }
 };
 
-int main()
+int main(int, char**)
 {
     const test t;
     assert(t.getloc().name() == std::string("C"));
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.base.locales/imbue.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.base.locales/imbue.pass.cpp
index 0fa77cb7ac215bb00bc6227deb4fc98f78a1eec7..ad8898a170f43f808182946c400f0e927e385716 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.base.locales/imbue.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.base.locales/imbue.pass.cpp
@@ -74,7 +74,7 @@ void f3(std::ios_base::event ev, std::ios_base& stream, int index)
     }
 }
 
-int main()
+int main(int, char**)
 {
     test t;
     std::ios_base& b = t;
@@ -87,4 +87,6 @@ int main()
     assert(f1_called);
     assert(f2_called);
     assert(f3_called);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.base.storage/iword.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.base.storage/iword.pass.cpp
index 467b885cebecac16884977817360df62633b4c5a..84eb18370c3fecd62bce55160b61a8acfe1adfe4 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.base.storage/iword.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.base.storage/iword.pass.cpp
@@ -29,7 +29,7 @@ public:
     }
 };
 
-int main()
+int main(int, char**)
 {
     test t;
     std::ios_base& b = t;
@@ -41,4 +41,6 @@ int main()
         for (int j = 0; j <= i; ++j)
             assert(b.iword(j) == j);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.base.storage/pword.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.base.storage/pword.pass.cpp
index 65aca332ac2b5d910cc752b485908f6dac7257c5..c4594615daab634ef0415866e8706c85619581a2 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.base.storage/pword.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.base.storage/pword.pass.cpp
@@ -30,7 +30,7 @@ public:
     }
 };
 
-int main()
+int main(int, char**)
 {
     test t;
     std::ios_base& b = t;
@@ -42,4 +42,6 @@ int main()
         for (std::intptr_t j = 0; j <= i; ++j)
             assert(b.pword(j) == (void*)j);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.base.storage/xalloc.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.base.storage/xalloc.pass.cpp
index dd95b26819f0046ba0403ca0c983b3449c45904b..2fcaddd6d54d4605e14dd5860f6b1cb61689336f 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.base.storage/xalloc.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.base.storage/xalloc.pass.cpp
@@ -15,11 +15,13 @@
 #include <ios>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert(std::ios_base::xalloc() == 0);
     assert(std::ios_base::xalloc() == 1);
     assert(std::ios_base::xalloc() == 2);
     assert(std::ios_base::xalloc() == 3);
     assert(std::ios_base::xalloc() == 4);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.members.static/sync_with_stdio.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.members.static/sync_with_stdio.pass.cpp
index 8937f2585bf26d3dbb3913240545fd9d2e2d5bbe..cd219971e549d96432e50b86c620082a8b0aa1f2 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.members.static/sync_with_stdio.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.members.static/sync_with_stdio.pass.cpp
@@ -13,7 +13,7 @@
 #include <ios>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert( std::ios_base::sync_with_stdio(false));
     assert(!std::ios_base::sync_with_stdio(false));
@@ -23,4 +23,6 @@ int main()
     assert( std::ios_base::sync_with_stdio(false));
     assert(!std::ios_base::sync_with_stdio());
     assert( std::ios_base::sync_with_stdio());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/ios_Init/tested_elsewhere.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/ios_Init/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/ios_Init/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/ios_Init/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/ios_failure/ctor_char_pointer_error_code.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/ios_failure/ctor_char_pointer_error_code.pass.cpp
index 0fc162599749c00772269515521785713a15b0cd..382aeda4f11ea0e2384883478ac117025aadfaee 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/ios_failure/ctor_char_pointer_error_code.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/ios_failure/ctor_char_pointer_error_code.pass.cpp
@@ -17,7 +17,7 @@
 #include <system_error>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::string what_arg("io test message");
@@ -37,4 +37,6 @@ int main()
         assert(what_message.find(std::iostream_category().message(static_cast<int>
             (std::io_errc::stream))) != std::string::npos);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/ios_failure/ctor_string_error_code.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/ios_failure/ctor_string_error_code.pass.cpp
index cc607d9458de9eff92ab49bfcfadc51454b96e32..610e6ad1527beebf75886f5e0cb2c3edc17b86f9 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/ios_failure/ctor_string_error_code.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/ios_failure/ctor_string_error_code.pass.cpp
@@ -17,7 +17,7 @@
 #include <system_error>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     // LWG2462 std::ios_base::failure is overspecified
     static_assert((std::is_base_of<std::system_error, std::ios_base::failure>::value), "");
@@ -40,4 +40,6 @@ int main()
         assert(what_message.find(std::iostream_category().message(static_cast<int>
             (std::io_errc::stream))) != std::string::npos);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/ios_fmtflags/fmtflags.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/ios_fmtflags/fmtflags.pass.cpp
index 6a51484f3f7889e491d52d7bfa745f6d3d732fef..2eed477b0dd48b48f82fa4b2321a82d326028be6 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/ios_fmtflags/fmtflags.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/ios_fmtflags/fmtflags.pass.cpp
@@ -32,7 +32,7 @@
 #include <ios>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert(std::ios_base::boolalpha);
     assert(std::ios_base::dec);
@@ -77,4 +77,6 @@ int main()
                                       | std::ios_base::hex));
     assert(std::ios_base::floatfield == (std::ios_base::scientific
                                        | std::ios_base::fixed));
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/ios_iostate/iostate.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/ios_iostate/iostate.pass.cpp
index 64123e5d1869146158ea4b6a9e6faa4498f02782..7e982f25f5f435a00548c8a3aa3d05915cdaf9cf 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/ios_iostate/iostate.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/ios_iostate/iostate.pass.cpp
@@ -18,7 +18,7 @@
 #include <ios>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert(std::ios_base::badbit);
     assert(std::ios_base::eofbit);
@@ -32,4 +32,6 @@ int main()
     );
 
     assert(std::ios_base::goodbit == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/ios_openmode/openmode.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/ios_openmode/openmode.pass.cpp
index 88c292955d3b17748257abd6c7f251ad39b6c091..ab21f96b7fcb9a14613f7b2548cd7c14369a31f4 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/ios_openmode/openmode.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/ios_openmode/openmode.pass.cpp
@@ -20,7 +20,7 @@
 #include <ios>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert(std::ios_base::app);
     assert(std::ios_base::ate);
@@ -38,4 +38,6 @@ int main()
         & std::ios_base::out
         & std::ios_base::trunc) == 0
     );
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/ios_seekdir/seekdir.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/ios_seekdir/seekdir.pass.cpp
index 3d0c80974fedd9858ce3c4bc13c95f789edc2562..dfa955c7f5538cc60fd3b8ca51528ebac9802cdd 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/ios_seekdir/seekdir.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/ios_seekdir/seekdir.pass.cpp
@@ -17,9 +17,11 @@
 #include <ios>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert(std::ios_base::beg != std::ios_base::cur);
     assert(std::ios_base::beg != std::ios_base::end);
     assert(std::ios_base::cur != std::ios_base::end);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/nothing_to_do.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios.base/ios.types/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios.base/nothing_to_do.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios.base/nothing_to_do.pass.cpp
index 8e23732f09f10dba4889b2092a941a065df2c278..c4eff25bcb146d16752be4246f25e0c9f1c6aa06 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios.base/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios.base/nothing_to_do.pass.cpp
@@ -10,6 +10,8 @@
 
 #include <ios>
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.cons/ctor_streambuf.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.cons/ctor_streambuf.pass.cpp
index 1bd33e96170bbb2b7f03512931b6f46f71fb577d..01c0d4679bc9f42547d82f4ad3aeee087ea6cc80 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.cons/ctor_streambuf.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.cons/ctor_streambuf.pass.cpp
@@ -16,7 +16,7 @@
 #include <streambuf>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::streambuf* sb = 0;
@@ -44,4 +44,6 @@ int main()
         assert(ios.fill() == ' ');
         assert(ios.getloc() == std::locale());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/copyfmt.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/copyfmt.pass.cpp
index 08d00c1c0a985fe329e8cbe657a5a807426ccda1..949c87e0b832c87eca1fb6c14b97f3276d45614f 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/copyfmt.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/copyfmt.pass.cpp
@@ -110,7 +110,7 @@ void g3(std::ios_base::event ev, std::ios_base& stream, int index)
     }
 }
 
-int main()
+int main(int, char**)
 {
     testbuf sb1;
     std::ios ios1(&sb1);
@@ -190,4 +190,6 @@ int main()
     assert(ios1.tie() == (std::ostream*)2);
     assert(ios1.fill() == '2');
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/fill.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/fill.pass.cpp
index b5cc96c338486bdcecea6bb52e317ae271df282e..f45c6c8b25c76ffc862e112700693110149380b7 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/fill.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/fill.pass.cpp
@@ -15,8 +15,10 @@
 #include <ios>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::ios ios(0);
     assert(ios.fill() == ' ');
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/fill_char_type.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/fill_char_type.pass.cpp
index b1c56ed539d24d24eb117a47749aea3fb295d246..1c42a03fb317b43c8bf424bb368015dda2195409 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/fill_char_type.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/fill_char_type.pass.cpp
@@ -15,11 +15,13 @@
 #include <ios>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     assert(ios.fill() == ' ');
     char c = ios.fill('*');
     assert(c == ' ');
     assert(ios.fill() == '*');
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/imbue.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/imbue.pass.cpp
index 3874372902f0a36554de6a516c66ecb56af194e8..ed0df788daa02068df33d7465b5bf55afc024bd3 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/imbue.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/imbue.pass.cpp
@@ -68,7 +68,7 @@ void f3(std::ios_base::event ev, std::ios_base& stream, int index)
     }
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::ios ios(0);
@@ -99,4 +99,6 @@ int main()
         assert(f2_called);
         assert(f3_called);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/move.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/move.pass.cpp
index 4c60756746e33955ded9a4ba2f0534f1fb88c4b3..5f99f3db0ae110485df297588fd59c5b5d3e8f23 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/move.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/move.pass.cpp
@@ -77,7 +77,7 @@ void g3(std::ios_base::event ev, std::ios_base&, int index)
     }
 }
 
-int main()
+int main(int, char**)
 {
     testios ios1;
     testbuf sb2;
@@ -136,4 +136,6 @@ int main()
 
     assert(ios2.rdbuf() == &sb2);
     assert(ios2.tie() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/narrow.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/narrow.pass.cpp
index b1ffc1e96d6fc6bafe197b75fd10165c63e80503..afab4ec5def5d7def68350be68ca592c1d9900d1 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/narrow.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/narrow.pass.cpp
@@ -15,9 +15,11 @@
 #include <ios>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::wios ios(0);
     assert(ios.narrow(L'c', '*') == 'c');
     assert(ios.narrow(L'\u203C', '*') == '*');
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/rdbuf.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/rdbuf.pass.cpp
index bc5871f924d831d9c1c869ef643ce1656351ce85..f104cada627142be1bc14ba982a4223951286767 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/rdbuf.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/rdbuf.pass.cpp
@@ -16,7 +16,7 @@
 #include <streambuf>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         const std::ios ios(0);
@@ -27,4 +27,6 @@ int main()
         const std::ios ios(sb);
         assert(ios.rdbuf() == sb);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/rdbuf_streambuf.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/rdbuf_streambuf.pass.cpp
index c1aa1aaf3deba6064ae83de06183869f965528be..5c4e24a82ebe72dfde7af5dfcec8238079f3dc1c 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/rdbuf_streambuf.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/rdbuf_streambuf.pass.cpp
@@ -16,7 +16,7 @@
 #include <streambuf>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     assert(ios.rdbuf() == 0);
@@ -30,4 +30,6 @@ int main()
     assert(sb2 == (std::streambuf*)1);
     assert(ios.rdbuf() == 0);
     assert(ios.bad());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/set_rdbuf.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/set_rdbuf.pass.cpp
index 65f66cb4b63dc92c15337c7ec8b620af84330efd..04b1b9ff6b04e07c5d547864298dd5e051a68f2c 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/set_rdbuf.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/set_rdbuf.pass.cpp
@@ -30,7 +30,7 @@ struct testios
     void set_rdbuf(std::streambuf* x) {std::ios::set_rdbuf(x);}
 };
 
-int main()
+int main(int, char**)
 {
     testbuf sb1;
     testbuf sb2;
@@ -60,4 +60,6 @@ int main()
 #endif
     ios.set_rdbuf(0);
     assert(ios.rdbuf() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/swap.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/swap.pass.cpp
index 559768b945b377730cd0bd24b8d1a1deced6cc6c..40e95bae7047b4c410bd9a530e317735cd5e76c9 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/swap.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/swap.pass.cpp
@@ -70,7 +70,7 @@ void g3(std::ios_base::event, std::ios_base&, int index)
     g3_called = true;
 }
 
-int main()
+int main(int, char**)
 {
     testbuf sb1;
     testios ios1(&sb1);
@@ -164,4 +164,6 @@ int main()
     ios2.imbue(std::locale("C"));
     assert(f1_called);
     assert(f2_called);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/tie.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/tie.pass.cpp
index 6ea816d7d1b73d2985782162c41dbf9a3ede9332..c0d7ac173324ad249e3c1d4f548c43bf03b1b93f 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/tie.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/tie.pass.cpp
@@ -15,8 +15,10 @@
 #include <ios>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::basic_ios<char> ios(0);
     assert(ios.tie() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/tie_ostream.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/tie_ostream.pass.cpp
index d2bb41c4e283a9acb8446f504c644257c595ca82..4ce5966add87080f7a599a8e0473696a92a138f5 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/tie_ostream.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/tie_ostream.pass.cpp
@@ -15,11 +15,13 @@
 #include <ios>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::ostream* os = (std::ostream*)1;
     std::ostream* r = ios.tie(os);
     assert(r == 0);
     assert(ios.tie() == os);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/widen.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/widen.pass.cpp
index a1585cd545ebf87ab071053b5a13f3c8eda763f0..0ae5637184ceb21c3804b0311293a11686074351 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/widen.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios/basic.ios.members/widen.pass.cpp
@@ -15,8 +15,10 @@
 #include <ios>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::ios ios(0);
     assert(ios.widen('c') == 'c');
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/bad.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/bad.pass.cpp
index 158c953a401049f1a3632829062726987a1b2817..2308cfa929f6e3b8699f48d6ced563074617da73 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/bad.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/bad.pass.cpp
@@ -18,7 +18,7 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     {
         std::ios ios(0);
@@ -37,4 +37,6 @@ int main()
         ios.setstate(std::ios::badbit);
         assert(ios.bad());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/bool.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/bool.pass.cpp
index 126431ce20de0c734951042c2edc23ddc1d85b5f..24fcbff39260c98bfd9928027522907a0ddec0b3 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/bool.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/bool.pass.cpp
@@ -18,7 +18,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     assert(static_cast<bool>(ios) == !ios.fail());
@@ -30,4 +30,6 @@ int main()
 #if TEST_STD_VER >= 11
     static_assert((!std::is_convertible<std::ios, bool>::value), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/clear.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/clear.pass.cpp
index 7938a84cfe4552900dad96f5f30b5eb1d7b4db1f..6fc38fde9baa36c049ea797ba5ebed6083fe2cfe 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/clear.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/clear.pass.cpp
@@ -20,7 +20,7 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     {
         std::ios ios(0);
@@ -66,4 +66,6 @@ int main()
         ios.clear(std::ios::eofbit);
         assert(ios.rdstate() == std::ios::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/eof.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/eof.pass.cpp
index bf65663427f6f44c84741c960672ff209fce4d56..bf1d0246d4d084d3112332ba45dcd83cfe967530 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/eof.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/eof.pass.cpp
@@ -18,7 +18,7 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     {
         std::ios ios(0);
@@ -33,4 +33,6 @@ int main()
         ios.setstate(std::ios::eofbit);
         assert(ios.eof());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/exceptions.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/exceptions.pass.cpp
index 9a6b3233f7fc1240672485ab93b337dba33e2f35..4632e004333fd33c5b4967654484d1280963a3de 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/exceptions.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/exceptions.pass.cpp
@@ -18,7 +18,7 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     {
         const std::ios ios(0);
@@ -29,4 +29,6 @@ int main()
         const std::ios ios(&sb);
         assert(ios.exceptions() == std::ios::goodbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/exceptions_iostate.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/exceptions_iostate.pass.cpp
index 1d56d475a9e27b94ad252df42e63c6be86c10055..b8b6577b243955b5482058a17264bdb6872c7ee3 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/exceptions_iostate.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/exceptions_iostate.pass.cpp
@@ -20,7 +20,7 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     {
         std::ios ios(0);
@@ -48,4 +48,6 @@ int main()
         ios.exceptions(std::ios::badbit);
         assert(ios.exceptions() == std::ios::badbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/fail.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/fail.pass.cpp
index a475c3589ab69a38f44a664b7fd3a5325584ac0d..3ae215e45f4892868e2b2c65955d60b15d026ef4 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/fail.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/fail.pass.cpp
@@ -18,7 +18,7 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     {
         std::ios ios(0);
@@ -37,4 +37,6 @@ int main()
         ios.setstate(std::ios::failbit);
         assert(ios.fail());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/good.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/good.pass.cpp
index e4f28bfe325c6adad371dee4ad1d3d796d453a84..19c05edce67b68b63335629bd2f17dee3fdff2b3 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/good.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/good.pass.cpp
@@ -18,7 +18,7 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     {
         std::ios ios(0);
@@ -31,4 +31,6 @@ int main()
         ios.setstate(std::ios::eofbit);
         assert(!ios.good());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/not.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/not.pass.cpp
index 151c2244e80bcfa54d8a9936d57c17a1ca45ef57..20ddb35dccaffa436f62b3b181ac2c826c64ddf2 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/not.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/not.pass.cpp
@@ -15,10 +15,12 @@
 #include <ios>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     assert(!ios == ios.fail());
     ios.setstate(std::ios::failbit);
     assert(!ios == ios.fail());
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/rdstate.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/rdstate.pass.cpp
index dde113a918c81368ae66f40134ca30829d137cd7..37886ac83e2c83c740e6f4e8c8f3689a2053686e 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/rdstate.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/rdstate.pass.cpp
@@ -15,10 +15,12 @@
 #include <ios>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     assert(ios.rdstate() == std::ios::badbit);
     ios.setstate(std::ios::failbit);
     assert(ios.rdstate() == (std::ios::failbit | std::ios::badbit));
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/setstate.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/setstate.pass.cpp
index 830dd448ef1ece444a3719c20b0b8bbdf5afae54..ea954bee05e906fbcfa8dba0139cecd148f534f0 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/setstate.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios/iostate.flags/setstate.pass.cpp
@@ -20,7 +20,7 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     {
         std::ios ios(0);
@@ -65,4 +65,6 @@ int main()
         ios.setstate(std::ios::failbit);
         assert(ios.rdstate() == (std::ios::eofbit | std::ios::failbit));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/ios/types.pass.cpp b/libcxx/test/std/input.output/iostreams.base/ios/types.pass.cpp
index 58165fc44441b7d7680bbae8f3c433365dc6a41e..b4a4d7c57d87c559dada80850a4255e767143a70 100644
--- a/libcxx/test/std/input.output/iostreams.base/ios/types.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/ios/types.pass.cpp
@@ -21,7 +21,7 @@
 #include <ios>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::ios_base, std::basic_ios<char> >::value), "");
     static_assert((std::is_same<std::basic_ios<char>::char_type, char>::value), "");
@@ -29,4 +29,6 @@ int main()
     static_assert((std::is_same<std::basic_ios<char>::int_type, std::char_traits<char>::int_type>::value), "");
     static_assert((std::is_same<std::basic_ios<char>::pos_type, std::char_traits<char>::pos_type>::value), "");
     static_assert((std::is_same<std::basic_ios<char>::off_type, std::char_traits<char>::off_type>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/is_error_code_enum_io_errc.pass.cpp b/libcxx/test/std/input.output/iostreams.base/is_error_code_enum_io_errc.pass.cpp
index c087871ea844d2de455ddf34953d410c7d2b40ac..76eb83148b398258e9a17219147f01cb8e537269 100644
--- a/libcxx/test/std/input.output/iostreams.base/is_error_code_enum_io_errc.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/is_error_code_enum_io_errc.pass.cpp
@@ -15,10 +15,12 @@
 #include <ios>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     static_assert(std::is_error_code_enum  <std::io_errc>::value, "");
 #if TEST_STD_VER > 14
     static_assert(std::is_error_code_enum_v<std::io_errc>, "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/adjustfield.manip/internal.pass.cpp b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/adjustfield.manip/internal.pass.cpp
index a214813984eaec6acf6e60144cac6967a560cc45..fba2e71ca7d3e7f58e092dad51b24e900d8b632d 100644
--- a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/adjustfield.manip/internal.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/adjustfield.manip/internal.pass.cpp
@@ -18,11 +18,13 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     testbuf sb;
     std::ios ios(&sb);
     std::ios_base& r = std::internal(ios);
     assert(&r == &ios);
     assert(ios.flags() & std::ios::internal);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/adjustfield.manip/left.pass.cpp b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/adjustfield.manip/left.pass.cpp
index 1073e2522be90e758aae4000ca5e455d10226b65..f89d6b9e78fffc714cc6d706634c9f66fd55988a 100644
--- a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/adjustfield.manip/left.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/adjustfield.manip/left.pass.cpp
@@ -18,11 +18,13 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     testbuf sb;
     std::ios ios(&sb);
     std::ios_base& r = std::left(ios);
     assert(&r == &ios);
     assert(ios.flags() & std::ios::left);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/adjustfield.manip/right.pass.cpp b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/adjustfield.manip/right.pass.cpp
index c391ab8c5006d998eb6a08a39af2a830019e422d..399d3ba51dcc36dc21e24cffb09fb940e187d43a 100644
--- a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/adjustfield.manip/right.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/adjustfield.manip/right.pass.cpp
@@ -18,11 +18,13 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     testbuf sb;
     std::ios ios(&sb);
     std::ios_base& r = std::right(ios);
     assert(&r == &ios);
     assert(ios.flags() & std::ios::right);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/basefield.manip/dec.pass.cpp b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/basefield.manip/dec.pass.cpp
index 64351b6b192c47adfcb95584f67101d61db1f2d6..98740cdc026b2be793fd210e8c30e7136b5bb5d2 100644
--- a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/basefield.manip/dec.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/basefield.manip/dec.pass.cpp
@@ -18,11 +18,13 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     testbuf sb;
     std::ios ios(&sb);
     std::ios_base& r = std::dec(ios);
     assert(&r == &ios);
     assert(ios.flags() & std::ios::dec);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/basefield.manip/hex.pass.cpp b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/basefield.manip/hex.pass.cpp
index cab0bc258345c9181b150cef46f42b84e6a8e156..39addcdcf24b5eb79ea8dd99dbd3d9d60fc70f36 100644
--- a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/basefield.manip/hex.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/basefield.manip/hex.pass.cpp
@@ -18,11 +18,13 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     testbuf sb;
     std::ios ios(&sb);
     std::ios_base& r = std::hex(ios);
     assert(&r == &ios);
     assert(ios.flags() & std::ios::hex);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/basefield.manip/oct.pass.cpp b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/basefield.manip/oct.pass.cpp
index a4073646c4e628bc15528e04a8ea934c327197bb..92b2d4ee7efad1524aef267aa40170da6049484a 100644
--- a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/basefield.manip/oct.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/basefield.manip/oct.pass.cpp
@@ -18,11 +18,13 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     testbuf sb;
     std::ios ios(&sb);
     std::ios_base& r = std::oct(ios);
     assert(&r == &ios);
     assert(ios.flags() & std::ios::oct);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/error.reporting/iostream_category.pass.cpp b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/error.reporting/iostream_category.pass.cpp
index 0517481b899a329d777fde84ab6d022a66c78e83..e017c632a4d9e5e5aaa3eb25eceec91f06a9b308 100644
--- a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/error.reporting/iostream_category.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/error.reporting/iostream_category.pass.cpp
@@ -14,9 +14,11 @@
 #include <cassert>
 #include <string>
 
-int main()
+int main(int, char**)
 {
     const std::error_category& e_cat1 = std::iostream_category();
     std::string m1 = e_cat1.name();
     assert(m1 == "iostream");
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/error.reporting/make_error_code.pass.cpp b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/error.reporting/make_error_code.pass.cpp
index 745349d14cbc40ab20f206b8b38cc5bdaed97afa..060b6284cac184312d0b9dbc01507140019eda37 100644
--- a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/error.reporting/make_error_code.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/error.reporting/make_error_code.pass.cpp
@@ -13,11 +13,13 @@
 #include <ios>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::error_code ec = make_error_code(std::io_errc::stream);
         assert(ec.value() == static_cast<int>(std::io_errc::stream));
         assert(ec.category() == std::iostream_category());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/error.reporting/make_error_condition.pass.cpp b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/error.reporting/make_error_condition.pass.cpp
index ce9f9f020522423c80497b2b9ec9016230ddeddf..3970708bfa02388051c316c69b577d2f3395805d 100644
--- a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/error.reporting/make_error_condition.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/error.reporting/make_error_condition.pass.cpp
@@ -13,11 +13,13 @@
 #include <ios>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         const std::error_condition ec1 = std::make_error_condition(std::io_errc::stream);
         assert(ec1.value() == static_cast<int>(std::io_errc::stream));
         assert(ec1.category() == std::iostream_category());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/floatfield.manip/defaultfloat.pass.cpp b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/floatfield.manip/defaultfloat.pass.cpp
index 7f04bbc51e7b3c1c5d344ecfa9366c1430adf3fa..bb8c424a162f45f4a692684f60c458359a2543d4 100644
--- a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/floatfield.manip/defaultfloat.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/floatfield.manip/defaultfloat.pass.cpp
@@ -18,7 +18,7 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     testbuf sb;
     std::ios ios(&sb);
@@ -26,4 +26,6 @@ int main()
     assert(&r == &ios);
     assert(!(ios.flags() & std::ios::fixed));
     assert(!(ios.flags() & std::ios::scientific));
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/floatfield.manip/fixed.pass.cpp b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/floatfield.manip/fixed.pass.cpp
index 8dbb7a1d8b4f50ea7f4ffbeb12d0ef80d8fabcb1..94cbf1a53d9ce79ea365abfc57be9250dcf2c7d7 100644
--- a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/floatfield.manip/fixed.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/floatfield.manip/fixed.pass.cpp
@@ -18,11 +18,13 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     testbuf sb;
     std::ios ios(&sb);
     std::ios_base& r = std::fixed(ios);
     assert(&r == &ios);
     assert(ios.flags() & std::ios::fixed);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/floatfield.manip/hexfloat.pass.cpp b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/floatfield.manip/hexfloat.pass.cpp
index 24afef8b86eade94f55e7a84a8930194331d1b9d..c24d7f999d92ca09c0e6d8ef498de3eb8fdc327b 100644
--- a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/floatfield.manip/hexfloat.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/floatfield.manip/hexfloat.pass.cpp
@@ -18,7 +18,7 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     testbuf sb;
     std::ios ios(&sb);
@@ -26,4 +26,6 @@ int main()
     assert(&r == &ios);
     assert(ios.flags() & std::ios::fixed);
     assert(ios.flags() & std::ios::scientific);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/floatfield.manip/scientific.pass.cpp b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/floatfield.manip/scientific.pass.cpp
index d84aa3775a060e2058eba581c4904f2109506789..c8a4819447befdacef324aff4041d688a252fef3 100644
--- a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/floatfield.manip/scientific.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/floatfield.manip/scientific.pass.cpp
@@ -18,11 +18,13 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     testbuf sb;
     std::ios ios(&sb);
     std::ios_base& r = std::scientific(ios);
     assert(&r == &ios);
     assert(ios.flags() & std::ios::scientific);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/boolalpha.pass.cpp b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/boolalpha.pass.cpp
index de58c17f060ca7ebe9e23cae876e35c16f265cc0..176267dd6fe8eefb62a83fc3148900b3c37d305a 100644
--- a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/boolalpha.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/boolalpha.pass.cpp
@@ -18,11 +18,13 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     testbuf sb;
     std::ios ios(&sb);
     std::ios_base& r = std::boolalpha(ios);
     assert(&r == &ios);
     assert(ios.flags() & std::ios::boolalpha);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/noboolalpha.pass.cpp b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/noboolalpha.pass.cpp
index f67ddabaea366dc7469511659664593d584af8ce..27d61cee7aa94e2b47ea939bdf12414f2c235d54 100644
--- a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/noboolalpha.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/noboolalpha.pass.cpp
@@ -18,7 +18,7 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     testbuf sb;
     std::ios ios(&sb);
@@ -26,4 +26,6 @@ int main()
     std::ios_base& r = std::noboolalpha(ios);
     assert(&r == &ios);
     assert(!(ios.flags() & std::ios::boolalpha));
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/noshowbase.pass.cpp b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/noshowbase.pass.cpp
index bd904ad641955bc9e15cd80b8b8d99dceef4b67f..b730afa88baf9ff19f619dfc8c0b1f5157d77eaa 100644
--- a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/noshowbase.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/noshowbase.pass.cpp
@@ -18,7 +18,7 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     testbuf sb;
     std::ios ios(&sb);
@@ -26,4 +26,6 @@ int main()
     std::ios_base& r = std::noshowbase(ios);
     assert(&r == &ios);
     assert(!(ios.flags() & std::ios::showbase));
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/noshowpoint.pass.cpp b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/noshowpoint.pass.cpp
index 97d9198014c8e11fce6c82c082f72879963d1046..0d9f33ea5c1d385abb237f23685bcb0c55f530d9 100644
--- a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/noshowpoint.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/noshowpoint.pass.cpp
@@ -18,7 +18,7 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     testbuf sb;
     std::ios ios(&sb);
@@ -26,4 +26,6 @@ int main()
     std::ios_base& r = std::noshowpoint(ios);
     assert(&r == &ios);
     assert(!(ios.flags() & std::ios::showpoint));
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/noshowpos.pass.cpp b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/noshowpos.pass.cpp
index 24f8bfca0b04ec5a6178bd47b159ef1fcbf9cb43..fa54cd647355d2214ae7cfed39de1db97d555198 100644
--- a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/noshowpos.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/noshowpos.pass.cpp
@@ -18,7 +18,7 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     testbuf sb;
     std::ios ios(&sb);
@@ -26,4 +26,6 @@ int main()
     std::ios_base& r = std::noshowpos(ios);
     assert(&r == &ios);
     assert(!(ios.flags() & std::ios::showpos));
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/noskipws.pass.cpp b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/noskipws.pass.cpp
index 5d24d3d4190facd5887643b74fe8db8221fe312a..9ee5ea8e61a37d626ee062f11e0267f9519992eb 100644
--- a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/noskipws.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/noskipws.pass.cpp
@@ -18,7 +18,7 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     testbuf sb;
     std::ios ios(&sb);
@@ -26,4 +26,6 @@ int main()
     std::ios_base& r = std::noskipws(ios);
     assert(&r == &ios);
     assert(!(ios.flags() & std::ios::skipws));
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/nounitbuf.pass.cpp b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/nounitbuf.pass.cpp
index 61a7dd29e83f23a8016ab50679be93de483f3ebd..ce06e12bd1198a3e5e8bf15d3f017c6fa471c519 100644
--- a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/nounitbuf.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/nounitbuf.pass.cpp
@@ -18,7 +18,7 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     testbuf sb;
     std::ios ios(&sb);
@@ -26,4 +26,6 @@ int main()
     std::ios_base& r = std::nounitbuf(ios);
     assert(&r == &ios);
     assert(!(ios.flags() & std::ios::unitbuf));
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/nouppercase.pass.cpp b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/nouppercase.pass.cpp
index 923a6ac754af41db57962d77069f5abc89cd2499..8e0554620997f3ff3c0c2c0c72b1ac1ec453ffb4 100644
--- a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/nouppercase.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/nouppercase.pass.cpp
@@ -18,7 +18,7 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     testbuf sb;
     std::ios ios(&sb);
@@ -26,4 +26,6 @@ int main()
     std::ios_base& r = std::nouppercase(ios);
     assert(&r == &ios);
     assert(!(ios.flags() & std::ios::uppercase));
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/showbase.pass.cpp b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/showbase.pass.cpp
index d584d3128a8b5316bf4b817f99adf595b352e54c..7f1338c5dbfd23e7f906ae1bcc2881a805520e1b 100644
--- a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/showbase.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/showbase.pass.cpp
@@ -18,11 +18,13 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     testbuf sb;
     std::ios ios(&sb);
     std::ios_base& r = std::showbase(ios);
     assert(&r == &ios);
     assert(ios.flags() & std::ios::showbase);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/showpoint.pass.cpp b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/showpoint.pass.cpp
index 6cfb73633d133beaa43ba152c88ad7209c6b53f6..03cf312d0f313b2fe1ff6badef1610e743793c55 100644
--- a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/showpoint.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/showpoint.pass.cpp
@@ -18,11 +18,13 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     testbuf sb;
     std::ios ios(&sb);
     std::ios_base& r = std::showpoint(ios);
     assert(&r == &ios);
     assert(ios.flags() & std::ios::showpoint);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/showpos.pass.cpp b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/showpos.pass.cpp
index 06f1dd836202ee5c2425b448cc92794641d7dcbd..2fb0d6511549f42cbfa15937c383dd9721d9fff8 100644
--- a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/showpos.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/showpos.pass.cpp
@@ -18,11 +18,13 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     testbuf sb;
     std::ios ios(&sb);
     std::ios_base& r = std::showpos(ios);
     assert(&r == &ios);
     assert(ios.flags() & std::ios::showpos);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/skipws.pass.cpp b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/skipws.pass.cpp
index b153bc84018c72633b2fd47575a233c27312a1f8..2c64cb8dfb1588032324707bec60de361fb64322 100644
--- a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/skipws.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/skipws.pass.cpp
@@ -18,11 +18,13 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     testbuf sb;
     std::ios ios(&sb);
     std::ios_base& r = std::skipws(ios);
     assert(&r == &ios);
     assert(ios.flags() & std::ios::skipws);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/unitbuf.pass.cpp b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/unitbuf.pass.cpp
index 22bcf5eb99e353b66225a99d2849b5d76551b638..6acedc6a5c2d4187166b8b7c38a253502608e024 100644
--- a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/unitbuf.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/unitbuf.pass.cpp
@@ -18,11 +18,13 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     testbuf sb;
     std::ios ios(&sb);
     std::ios_base& r = std::unitbuf(ios);
     assert(&r == &ios);
     assert(ios.flags() & std::ios::unitbuf);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/uppercase.pass.cpp b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/uppercase.pass.cpp
index cc2a4bc45e8bb14e4c668fa935a45bbbfc56664a..e97763fff03c25694c3e95dd27ce212c19d8466c 100644
--- a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/uppercase.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/fmtflags.manip/uppercase.pass.cpp
@@ -18,11 +18,13 @@
 
 struct testbuf : public std::streambuf {};
 
-int main()
+int main(int, char**)
 {
     testbuf sb;
     std::ios ios(&sb);
     std::ios_base& r = std::uppercase(ios);
     assert(&r == &ios);
     assert(ios.flags() & std::ios::uppercase);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/nothing_to_do.pass.cpp b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/input.output/iostreams.base/std.ios.manip/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/std.ios.manip/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/stream.types/streamoff.pass.cpp b/libcxx/test/std/input.output/iostreams.base/stream.types/streamoff.pass.cpp
index aaa5b871ac226b8b333fedf6b4dc5264edb63fa1..20b953d5527585601b1086f5753e93fbcabac3bc 100644
--- a/libcxx/test/std/input.output/iostreams.base/stream.types/streamoff.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/stream.types/streamoff.pass.cpp
@@ -13,8 +13,10 @@
 #include <ios>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert(std::is_integral<std::streamoff>::value, "");
     static_assert(std::is_signed<std::streamoff>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.base/stream.types/streamsize.pass.cpp b/libcxx/test/std/input.output/iostreams.base/stream.types/streamsize.pass.cpp
index 670932324561359fc6d95bfe3a4698ac1b1634fc..50fa21e8d52c2daa23b0191b0c64af8ada25c76c 100644
--- a/libcxx/test/std/input.output/iostreams.base/stream.types/streamsize.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.base/stream.types/streamsize.pass.cpp
@@ -13,8 +13,10 @@
 #include <ios>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert(std::is_integral<std::streamsize>::value, "");
     static_assert(std::is_signed<std::streamsize>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.requirements/iostream.limits.imbue/tested_elsewhere.pass.cpp b/libcxx/test/std/input.output/iostreams.requirements/iostream.limits.imbue/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/input.output/iostreams.requirements/iostream.limits.imbue/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.requirements/iostream.limits.imbue/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.requirements/iostreams.limits.pos/nothing_to_do.pass.cpp b/libcxx/test/std/input.output/iostreams.requirements/iostreams.limits.pos/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/input.output/iostreams.requirements/iostreams.limits.pos/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.requirements/iostreams.limits.pos/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.requirements/iostreams.threadsafety/nothing_to_do.pass.cpp b/libcxx/test/std/input.output/iostreams.requirements/iostreams.threadsafety/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/input.output/iostreams.requirements/iostreams.threadsafety/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.requirements/iostreams.threadsafety/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/iostreams.requirements/nothing_to_do.pass.cpp b/libcxx/test/std/input.output/iostreams.requirements/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/input.output/iostreams.requirements/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/input.output/iostreams.requirements/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/nothing_to_do.pass.cpp b/libcxx/test/std/input.output/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/input.output/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/input.output/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf.reqts/tested_elsewhere.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf.reqts/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf.reqts/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf.reqts/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.cons/copy.fail.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.cons/copy.fail.cpp
index b94714212b100e22059081579ec12e29cfb22f69..285485087b42d88961bb915b6913554882a4ce56 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.cons/copy.fail.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.cons/copy.fail.cpp
@@ -18,7 +18,9 @@
 
 std::streambuf &get();
 
-int main()
+int main(int, char**)
 {
     std::streambuf sb = get(); // expected-error {{calling a protected constructor}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.cons/copy.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.cons/copy.pass.cpp
index c298992917483c6bccf9d47916a44e3103f7b995..405c72995912e9ecc7d8fcf92a14ac02de2427cd 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.cons/copy.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.cons/copy.pass.cpp
@@ -49,7 +49,7 @@ struct test
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         test<char> t;
@@ -82,4 +82,6 @@ int main()
         test<wchar_t> t;
         test<wchar_t> t2 = t;
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.cons/default.fail.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.cons/default.fail.cpp
index 76d47f2a23771b3109133e6452f0c9f9407f6c4c..ec7650ae04e5093376e34536d46d2a2dffd28d9a 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.cons/default.fail.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.cons/default.fail.cpp
@@ -15,7 +15,9 @@
 
 #include <streambuf>
 
-int main()
+int main(int, char**)
 {
     std::basic_streambuf<char> sb;
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.cons/default.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.cons/default.pass.cpp
index 9eebf255760bd9bf25259578827a9d2c0c80dba5..15475d3d68426789aff1e27c91239a7627b58845 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.cons/default.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.cons/default.pass.cpp
@@ -35,7 +35,7 @@ struct test
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         test<char> t;
@@ -54,4 +54,6 @@ int main()
         test<wchar_t> t;
         assert(t.getloc().name() == LOCALE_en_US_UTF_8);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/nothing_to_do.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.buffer/pubseekoff.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.buffer/pubseekoff.pass.cpp
index 741b71e38c2db6425b8db9e259351ae41ecb1249..b49fc2094ed95100597457232f2b3f13201e9cd8 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.buffer/pubseekoff.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.buffer/pubseekoff.pass.cpp
@@ -24,11 +24,13 @@ struct test
     test() {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         test<char> t;
         assert(t.pubseekoff(0, std::ios_base::beg) == -1);
         assert(t.pubseekoff(0, std::ios_base::beg, std::ios_base::app) == -1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.buffer/pubseekpos.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.buffer/pubseekpos.pass.cpp
index 2e14de9d28fee0ebc18a59547b31c307064ed195..1095c9148c7bd4d59e3e5c993120c7736ff6cb98 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.buffer/pubseekpos.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.buffer/pubseekpos.pass.cpp
@@ -24,10 +24,12 @@ struct test
     test() {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         test<char> t;
         assert(t.pubseekpos(0, std::ios_base::app) == -1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.buffer/pubsetbuf.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.buffer/pubsetbuf.pass.cpp
index fae4dd78fd697daf47d0040f51456013cbfd45c3..c0efb1710abf9cf9bc0814bb8db68bb5d2da40b9 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.buffer/pubsetbuf.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.buffer/pubsetbuf.pass.cpp
@@ -23,10 +23,12 @@ struct test
     test() {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         test<char> t;
         assert(t.pubsetbuf(0, 0) == &t);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.buffer/pubsync.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.buffer/pubsync.pass.cpp
index 8433a9f31a968ab543912f17143ca24ac2ca7634..8d7528ee2619411ce5f2fc42426afc6060740625 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.buffer/pubsync.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.buffer/pubsync.pass.cpp
@@ -23,10 +23,12 @@ struct test
     test() {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         test<char> t;
         assert(t.pubsync() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.locales/locales.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.locales/locales.pass.cpp
index ed1d43a8666c6b0942b8e86de606b0d612af6d3a..835944fcf310e6f1f9189c3bae66dc2f0d3f4354 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.locales/locales.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.locales/locales.pass.cpp
@@ -34,7 +34,7 @@ struct test
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         test<char> t;
@@ -48,4 +48,6 @@ int main()
                LOCALE_en_US_UTF_8);
         assert(t.getloc().name() == LOCALE_fr_FR_UTF_8);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.get/in_avail.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.get/in_avail.pass.cpp
index ea51ac64df15fe7fa9993d940d6a58533fd0d4d6..6d11a8e89690a51788f127aaf536b608ae27ba6d 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.get/in_avail.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.get/in_avail.pass.cpp
@@ -38,7 +38,7 @@ protected:
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         test<char> t;
@@ -48,4 +48,6 @@ int main()
         t.setg(in, in+2, in+5);
         assert(t.in_avail() == 3);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.get/sbumpc.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.get/sbumpc.pass.cpp
index 4aa7a81818b3722e233dc30942e6792f2ebf1945..4ac2d6fe547f6762dfc3eeed16d1104a86d15160 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.get/sbumpc.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.get/sbumpc.pass.cpp
@@ -38,7 +38,7 @@ protected:
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         test t;
@@ -52,4 +52,6 @@ int main()
         assert(t.sbumpc() == 'B');
         assert(uflow_called == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.get/sgetc.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.get/sgetc.pass.cpp
index 2a48158fd41c8cb5a2da4c7ae65bf21fa9dc3f29..8baefb279cf3385a1bfd8d10965b341b0d202435 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.get/sgetc.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.get/sgetc.pass.cpp
@@ -38,7 +38,7 @@ protected:
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         test t;
@@ -52,4 +52,6 @@ int main()
         assert(t.sgetc() == 'A');
         assert(underflow_called == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.get/sgetn.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.get/sgetn.pass.cpp
index 59804043cb09cf105ee9bd8611f830aae99d5c8a..9088ed846b94352b41cbdc6ea465ba9613f8d4a0 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.get/sgetn.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.get/sgetn.pass.cpp
@@ -31,10 +31,12 @@ protected:
     }
 };
 
-int main()
+int main(int, char**)
 {
     test t;
     assert(xsgetn_called == 0);
     assert(t.sgetn(0, 0) == 10);
     assert(xsgetn_called == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.get/snextc.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.get/snextc.pass.cpp
index 830f27282efd02a254e0b5e20f12c23ca154a60e..54965bca2fc7847e30668cfdedaed7ca03de2a00 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.get/snextc.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.get/snextc.pass.cpp
@@ -38,7 +38,7 @@ protected:
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         test t;
@@ -52,4 +52,6 @@ int main()
         assert(t.snextc() == 'C');
         assert(uflow_called == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.pback/sputbackc.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.pback/sputbackc.pass.cpp
index a2546b810dff65a2426782d1bdd24bef66ed2385..3b63ba3cef9cc499e4ea09d9deee569e46921aee 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.pback/sputbackc.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.pback/sputbackc.pass.cpp
@@ -38,7 +38,7 @@ protected:
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         test t;
@@ -52,4 +52,6 @@ int main()
         assert(t.sputbackc('A') == 'a');
         assert(pbackfail_called == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.pback/sungetc.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.pback/sungetc.pass.cpp
index dcdec61a3d4e647bb33872bf3285a63c7d024bc7..07c1600b0b2f4bb1f0715487c6146202ce939e90 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.pback/sungetc.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.pback/sungetc.pass.cpp
@@ -38,7 +38,7 @@ protected:
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         test t;
@@ -52,4 +52,6 @@ int main()
         assert(t.sungetc() == 'a');
         assert(pbackfail_called == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.put/sputc.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.put/sputc.pass.cpp
index 3d04924b160194240b0975ed0e468797d4045886..989b61d4e191e2826ad55e52597572f257f42200 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.put/sputc.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.put/sputc.pass.cpp
@@ -42,7 +42,7 @@ protected:
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         test t;
@@ -59,4 +59,6 @@ int main()
         assert(out[0] == 'A');
         assert(out[1] == 'B');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.put/sputn.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.put/sputn.pass.cpp
index bb865636ca33b329b5e78164604ad5755767c3d5..01bd9d487d830f0362ee7b9da15ef42b964554f6 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.put/sputn.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.members/streambuf.pub.put/sputn.pass.cpp
@@ -31,10 +31,12 @@ protected:
     }
 };
 
-int main()
+int main(int, char**)
 {
     test t;
     assert(xsputn_called == 0);
     assert(t.sputn(0, 0) == 5);
     assert(xsputn_called == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/nothing_to_do.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.assign/assign.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.assign/assign.pass.cpp
index 0c1cd4efbf9b883d487c9a812ed277fbab98726a..6109a6aa47168afa4a9f34acbf881fd822791896 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.assign/assign.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.assign/assign.pass.cpp
@@ -50,7 +50,7 @@ struct test
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         test<char> t;
@@ -89,4 +89,6 @@ int main()
         test<wchar_t> t2;
         t2 = t;
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.assign/swap.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.assign/swap.pass.cpp
index 6ece9aa57cf6a4706216b26f16a16613cbdff61e..2809d63124fbeaf77a4258b39a9cdaad5d361399 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.assign/swap.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.assign/swap.pass.cpp
@@ -59,7 +59,7 @@ struct test
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         test<char> t;
@@ -98,4 +98,6 @@ int main()
         test<wchar_t> t2;
         t2.swap(t);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.get.area/gbump.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.get.area/gbump.pass.cpp
index 015a7daa2f7c69848e6a5aee3adb4cecbdb40a92..161461dee95217520283b319a7692ab5cd2036f7 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.get.area/gbump.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.get.area/gbump.pass.cpp
@@ -41,7 +41,7 @@ struct test
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         test<char> t;
@@ -55,4 +55,6 @@ int main()
         t.setg(in, in+1, in+sizeof(in)/sizeof(in[0]));
         t.gbump(3);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.get.area/setg.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.get.area/setg.pass.cpp
index 74152974c07cc3f895295eee738ea43e4744351a..b303465f02da2870f3665f621e5390f4f6f9cfb7 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.get.area/setg.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.get.area/setg.pass.cpp
@@ -33,7 +33,7 @@ struct test
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         test<char> t;
@@ -45,4 +45,6 @@ int main()
         wchar_t in[] = L"ABC";
         t.setg(in, in+1, in+sizeof(in)/sizeof(in[0]));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.put.area/pbump.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.put.area/pbump.pass.cpp
index 92b869d31e5a6db49b74dc409a7744889ccc6787..e151d32273c25daa6c883d86f5e6826f5879ece2 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.put.area/pbump.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.put.area/pbump.pass.cpp
@@ -41,7 +41,7 @@ struct test
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         test<char> t;
@@ -57,4 +57,6 @@ int main()
         t.pbump(3);
         t.pbump(1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.put.area/pbump2gig.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.put.area/pbump2gig.pass.cpp
index 5811c90196f0729bf6d276d8a5970fbada05a698..eee48f3dfdb127c61d13ae72fa103efdfd421559 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.put.area/pbump2gig.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.put.area/pbump2gig.pass.cpp
@@ -26,7 +26,7 @@ struct SB : std::stringbuf
   const char* pubpptr() const { return pptr(); }
 };
 
-int main()
+int main(int, char**)
 {
 #ifndef TEST_HAS_NO_EXCEPTIONS
     try {
@@ -40,4 +40,6 @@ int main()
     catch (const std::length_error &) {} // maybe the string can't take 2GB
     catch (const std::bad_alloc    &) {} // maybe we don't have enough RAM
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.put.area/setp.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.put.area/setp.pass.cpp
index 12f955360c9af5f357b655d8a86fcb02e2ae99ac..6ca36227b53c56ba3339fe749e1a188f94f45b75 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.put.area/setp.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.put.area/setp.pass.cpp
@@ -33,7 +33,7 @@ struct test
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         test<char> t;
@@ -45,4 +45,6 @@ int main()
         wchar_t in[] = L"ABC";
         t.setp(in, in+sizeof(in)/sizeof(in[0]));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/nothing_to_do.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.buffer/tested_elsewhere.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.buffer/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.buffer/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.buffer/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.get/showmanyc.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.get/showmanyc.pass.cpp
index b31408e952d94870a1f13ffb8c9e7e8772e13cc5..5a238e8845522a039d0fb64dcded355804dbec81 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.get/showmanyc.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.get/showmanyc.pass.cpp
@@ -25,8 +25,10 @@ struct test
     test() {}
 };
 
-int main()
+int main(int, char**)
 {
     test<char> t;
     assert(t.in_avail() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.get/uflow.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.get/uflow.pass.cpp
index 1d1ee519f58e7a6e054a2399fb864c04c9fcfd3b..2f86c3b1a961f7943157a24b5ea1e81567d3779d 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.get/uflow.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.get/uflow.pass.cpp
@@ -25,8 +25,10 @@ struct test
 
 };
 
-int main()
+int main(int, char**)
 {
     test t;
     assert(t.sgetc() == -1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.get/underflow.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.get/underflow.pass.cpp
index 2422c52e54b4639729823b46b019130707ae4465..1d2ce7c5c23521bfebab3bec639acffcd203cd70 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.get/underflow.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.get/underflow.pass.cpp
@@ -22,8 +22,10 @@ struct test
     test() {}
 };
 
-int main()
+int main(int, char**)
 {
     test t;
     assert(t.sgetc() == -1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.get/xsgetn.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.get/xsgetn.pass.cpp
index 7c5f6b9d6fe56c14b55c86639481e2819d8770b9..f5a95821b28c8aecd3af6a00b09f41698a0f0d38 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.get/xsgetn.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.get/xsgetn.pass.cpp
@@ -30,7 +30,7 @@ struct test
     }
 };
 
-int main()
+int main(int, char**)
 {
     test t;
     char input[7] = "123456";
@@ -38,4 +38,6 @@ int main()
     char output[sizeof(input)] = {0};
     assert(t.sgetn(output, 10) == 7);
     assert(std::strcmp(input, output) == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.locales/nothing_to_do.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.locales/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.locales/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.locales/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.pback/pbackfail.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.pback/pbackfail.pass.cpp
index 1f243e958d60ad0e85c9b4da3797023e86d39eb6..217ff8c32fcbbbe6b0460dca02da0df70fdff7cb 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.pback/pbackfail.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.pback/pbackfail.pass.cpp
@@ -24,8 +24,10 @@ struct test
     test() {}
 };
 
-int main()
+int main(int, char**)
 {
     test t;
     assert(t.sputbackc('A') == -1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.put/overflow.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.put/overflow.pass.cpp
index ae52b9539ee5901c68a9134d39e7f3e15fedadd0..e067088f50b40df93b1771a7840f9181013d61b4 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.put/overflow.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.put/overflow.pass.cpp
@@ -22,8 +22,10 @@ struct test
     test() {}
 };
 
-int main()
+int main(int, char**)
 {
     test t;
     assert(t.sputc('A') == -1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.put/xsputn.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.put/xsputn.pass.cpp
index 15d3740412295eb8ca912dbccdedaecd23f4809a..1c30c8f2836e44713ba4f30daebc9f517535b72a 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.put/xsputn.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/streambuf.virtuals/streambuf.virt.put/xsputn.pass.cpp
@@ -30,7 +30,7 @@ struct test
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         test t;
@@ -41,4 +41,6 @@ int main()
         assert(t.sputn(in, sizeof(in)) == sizeof(in));
         assert(std::strcmp(in, out) == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/stream.buffers/streambuf/types.pass.cpp b/libcxx/test/std/input.output/stream.buffers/streambuf/types.pass.cpp
index d6ea963df275e47be3fefce7a1c4e8556f822a5c..434f8e3ec12ae4c13049fbf4c30650d123d3fed8 100644
--- a/libcxx/test/std/input.output/stream.buffers/streambuf/types.pass.cpp
+++ b/libcxx/test/std/input.output/stream.buffers/streambuf/types.pass.cpp
@@ -22,7 +22,7 @@
 #include <streambuf>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::streambuf::char_type, char>::value), "");
     static_assert((std::is_same<std::streambuf::traits_type, std::char_traits<char> >::value), "");
@@ -35,4 +35,6 @@ int main()
     static_assert((std::is_same<std::wstreambuf::int_type, std::char_traits<wchar_t>::int_type>::value), "");
     static_assert((std::is_same<std::wstreambuf::pos_type, std::char_traits<wchar_t>::pos_type>::value), "");
     static_assert((std::is_same<std::wstreambuf::off_type, std::char_traits<wchar_t>::off_type>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/istringstream/istringstream.assign/member_swap.pass.cpp b/libcxx/test/std/input.output/string.streams/istringstream/istringstream.assign/member_swap.pass.cpp
index cb4644aad4356bb84a2c52bb72aa99bc0ae1ad44..d0a5863ed848939552e1aa0035921ae9185e7c28 100644
--- a/libcxx/test/std/input.output/string.streams/istringstream/istringstream.assign/member_swap.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/istringstream/istringstream.assign/member_swap.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::istringstream ss0(" 123 456");
@@ -52,4 +52,6 @@ int main()
         ss0 >> i;
         assert(i == 321);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/istringstream/istringstream.assign/move.pass.cpp b/libcxx/test/std/input.output/string.streams/istringstream/istringstream.assign/move.pass.cpp
index b906db8d5bfcf5f2e987318a4bf40aa89f7320a9..5677959438ff2f2365c9398c246f733beba8e8d7 100644
--- a/libcxx/test/std/input.output/string.streams/istringstream/istringstream.assign/move.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/istringstream/istringstream.assign/move.pass.cpp
@@ -18,7 +18,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::istringstream ss0(" 123 456");
@@ -82,4 +82,6 @@ int main()
         s1 >> s;
         assert(s == L"Dddddddddddddddddd");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/istringstream/istringstream.assign/nonmember_swap.pass.cpp b/libcxx/test/std/input.output/string.streams/istringstream/istringstream.assign/nonmember_swap.pass.cpp
index 09b6e4b3996dbad1824d65c5d703cd5c7e90f11b..b8b00310dbe6a95ad06b14ba9444c52325bf9ba4 100644
--- a/libcxx/test/std/input.output/string.streams/istringstream/istringstream.assign/nonmember_swap.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/istringstream/istringstream.assign/nonmember_swap.pass.cpp
@@ -19,7 +19,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::istringstream ss0(" 123 456");
@@ -55,4 +55,6 @@ int main()
         ss0 >> i;
         assert(i == 321);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/istringstream/istringstream.cons/default.pass.cpp b/libcxx/test/std/input.output/string.streams/istringstream/istringstream.cons/default.pass.cpp
index 327c4ca124d48710131bba6102f5c640fd8ac8df..414c2269581ecbb0a9ca988f852d5f7433c49738 100644
--- a/libcxx/test/std/input.output/string.streams/istringstream/istringstream.cons/default.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/istringstream/istringstream.cons/default.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::istringstream ss;
@@ -42,4 +42,6 @@ int main()
         assert(ss.good());
         assert(ss.str() == L"");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/istringstream/istringstream.cons/move.pass.cpp b/libcxx/test/std/input.output/string.streams/istringstream/istringstream.cons/move.pass.cpp
index c5b144b09209557cfa190359518c45ab393f4a12..27eb5a745c81858ee15262c34266a494b0809d45 100644
--- a/libcxx/test/std/input.output/string.streams/istringstream/istringstream.cons/move.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/istringstream/istringstream.cons/move.pass.cpp
@@ -18,7 +18,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::istringstream ss0(" 123 456");
@@ -44,4 +44,6 @@ int main()
         ss >> i;
         assert(i == 456);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/istringstream/istringstream.cons/string.pass.cpp b/libcxx/test/std/input.output/string.streams/istringstream/istringstream.cons/string.pass.cpp
index cf3c7d89130b55e6ffd48f07d3e6454da0019fc8..04733d6042f9339345fe37ae86c3ea6fb7e52262 100644
--- a/libcxx/test/std/input.output/string.streams/istringstream/istringstream.cons/string.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/istringstream/istringstream.cons/string.pass.cpp
@@ -17,7 +17,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::istringstream ss(" 123 456");
@@ -63,4 +63,6 @@ int main()
         ss >> i;
         assert(i == 456);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/istringstream/istringstream.members/str.pass.cpp b/libcxx/test/std/input.output/string.streams/istringstream/istringstream.members/str.pass.cpp
index 9b706a535ac0a343763b8d17895e357e6137324b..4c010e2b4346b9189ed046d515c33e03b9145340 100644
--- a/libcxx/test/std/input.output/string.streams/istringstream/istringstream.members/str.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/istringstream/istringstream.members/str.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::istringstream ss(" 123 456");
@@ -52,4 +52,6 @@ int main()
         ss >> i;
         assert(i == 789);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/istringstream/types.pass.cpp b/libcxx/test/std/input.output/string.streams/istringstream/types.pass.cpp
index 0f256cbbdd43aa3539bc387a8c40444178cc780c..973196442297440e3e10f3f1c0ada8db901e08cb 100644
--- a/libcxx/test/std/input.output/string.streams/istringstream/types.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/istringstream/types.pass.cpp
@@ -23,7 +23,7 @@
 #include <sstream>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::basic_istream<char>, std::basic_istringstream<char> >::value), "");
     static_assert((std::is_same<std::basic_istringstream<char>::char_type, char>::value), "");
@@ -32,4 +32,6 @@ int main()
     static_assert((std::is_same<std::basic_istringstream<char>::pos_type, std::char_traits<char>::pos_type>::value), "");
     static_assert((std::is_same<std::basic_istringstream<char>::off_type, std::char_traits<char>::off_type>::value), "");
     static_assert((std::is_same<std::basic_istringstream<char>::allocator_type, std::allocator<char> >::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/ostringstream/ostringstream.assign/member_swap.pass.cpp b/libcxx/test/std/input.output/string.streams/ostringstream/ostringstream.assign/member_swap.pass.cpp
index af5622ee2c9734dc4cc04c5e5f6ab9e3e573bbdb..01cc58ae6ae3b7f006d3e36a43011cfb397b9165 100644
--- a/libcxx/test/std/input.output/string.streams/ostringstream/ostringstream.assign/member_swap.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/ostringstream/ostringstream.assign/member_swap.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::ostringstream ss0(" 123 456");
@@ -44,4 +44,6 @@ int main()
         ss0 << i << ' ' << 567;
         assert(ss0.str() == L"234 567");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/ostringstream/ostringstream.assign/move.pass.cpp b/libcxx/test/std/input.output/string.streams/ostringstream/ostringstream.assign/move.pass.cpp
index f44b0fba41af438191f546efc6fc28f38f56f0a6..bad3c7316d22892276114d4448af073f3069f984 100644
--- a/libcxx/test/std/input.output/string.streams/ostringstream/ostringstream.assign/move.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/ostringstream/ostringstream.assign/move.pass.cpp
@@ -18,7 +18,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::ostringstream ss0(" 123 456");
@@ -42,4 +42,6 @@ int main()
         ss << i << ' ' << 567;
         assert(ss.str() == L"234 5676");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/ostringstream/ostringstream.assign/nonmember_swap.pass.cpp b/libcxx/test/std/input.output/string.streams/ostringstream/ostringstream.assign/nonmember_swap.pass.cpp
index 0793fd295cf1aa999325c46284da7902c868cd27..d251e6e085f072b01306b22d0a35480e0e029ee0 100644
--- a/libcxx/test/std/input.output/string.streams/ostringstream/ostringstream.assign/nonmember_swap.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/ostringstream/ostringstream.assign/nonmember_swap.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::ostringstream ss0(" 123 456");
@@ -44,4 +44,6 @@ int main()
         ss0 << i << ' ' << 567;
         assert(ss0.str() == L"234 567");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/ostringstream/ostringstream.cons/default.pass.cpp b/libcxx/test/std/input.output/string.streams/ostringstream/ostringstream.cons/default.pass.cpp
index 79e0f614c5ad89ac667e5437706b780eafd0a0ae..f772a9040072cebeb50def630e63fda83b521f52 100644
--- a/libcxx/test/std/input.output/string.streams/ostringstream/ostringstream.cons/default.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/ostringstream/ostringstream.cons/default.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::ostringstream ss;
@@ -42,4 +42,6 @@ int main()
         assert(ss.good());
         assert(ss.str() == L"");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/ostringstream/ostringstream.cons/move.pass.cpp b/libcxx/test/std/input.output/string.streams/ostringstream/ostringstream.cons/move.pass.cpp
index 569310174b81d6ad8c2af494e7f175f43b1d138a..3b562bafd52f4e12bca68541bbc38e82fae2e760 100644
--- a/libcxx/test/std/input.output/string.streams/ostringstream/ostringstream.cons/move.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/ostringstream/ostringstream.cons/move.pass.cpp
@@ -18,7 +18,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::ostringstream ss0(" 123 456");
@@ -40,4 +40,6 @@ int main()
         ss << i << ' ' << 567;
         assert(ss.str() == L"234 5676");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/ostringstream/ostringstream.cons/string.pass.cpp b/libcxx/test/std/input.output/string.streams/ostringstream/ostringstream.cons/string.pass.cpp
index 8d64dd5e5f173c6842b2ff0ae5c31629ef9d3c99..98782dce1f6e251854c428fce721216bbf1d9c4f 100644
--- a/libcxx/test/std/input.output/string.streams/ostringstream/ostringstream.cons/string.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/ostringstream/ostringstream.cons/string.pass.cpp
@@ -17,7 +17,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::ostringstream ss(" 123 456");
@@ -55,4 +55,6 @@ int main()
         ss << i << ' ' << 567;
         assert(ss.str() == L"234 5676");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/ostringstream/ostringstream.members/str.pass.cpp b/libcxx/test/std/input.output/string.streams/ostringstream/ostringstream.members/str.pass.cpp
index d74acf3a588ca86e4639d256cc16fde2eb12c48d..56a85159ccae1b32fa9c699bec481bd10031fa2d 100644
--- a/libcxx/test/std/input.output/string.streams/ostringstream/ostringstream.members/str.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/ostringstream/ostringstream.members/str.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::ostringstream ss(" 123 456");
@@ -48,4 +48,6 @@ int main()
         ss << L"abc";
         assert(ss.str() == L"abc9");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/ostringstream/types.pass.cpp b/libcxx/test/std/input.output/string.streams/ostringstream/types.pass.cpp
index 15e7dc61fafbeb1edb14b44cade91aa44427ae0a..0da5f98d46ffd75894f112f7d421f3c5a8deaf0e 100644
--- a/libcxx/test/std/input.output/string.streams/ostringstream/types.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/ostringstream/types.pass.cpp
@@ -23,7 +23,7 @@
 #include <sstream>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::basic_ostream<char>, std::basic_ostringstream<char> >::value), "");
     static_assert((std::is_same<std::basic_ostringstream<char>::char_type, char>::value), "");
@@ -32,4 +32,6 @@ int main()
     static_assert((std::is_same<std::basic_ostringstream<char>::pos_type, std::char_traits<char>::pos_type>::value), "");
     static_assert((std::is_same<std::basic_ostringstream<char>::off_type, std::char_traits<char>::off_type>::value), "");
     static_assert((std::is_same<std::basic_ostringstream<char>::allocator_type, std::allocator<char> >::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.assign/member_swap.pass.cpp b/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.assign/member_swap.pass.cpp
index b5dce8fb9140fd54ba14f53563310831ef496e5e..6977d3189cf8381bc462d0196b3fbfbe8cf44b97 100644
--- a/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.assign/member_swap.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.assign/member_swap.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::stringbuf buf1("testing");
@@ -60,4 +60,6 @@ int main()
         assert(buf.str() == L"testing");
         assert(buf1.str() == L"");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.assign/move.pass.cpp b/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.assign/move.pass.cpp
index 2a469ebb79a7556fce1547619fd16cb348b183e8..653edc0d19cb720fa6b4f2e190ec2dd08beafdce 100644
--- a/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.assign/move.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.assign/move.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::stringbuf buf1("testing");
@@ -54,4 +54,6 @@ int main()
         buf = move(buf1);
         assert(buf.str() == L"testing");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.assign/nonmember_swap.pass.cpp b/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.assign/nonmember_swap.pass.cpp
index 5a57f902af36b79543e0107deedda58a41f4ee39..38562fc32205724f50e126bcea0cc12c12cd5ed0 100644
--- a/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.assign/nonmember_swap.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.assign/nonmember_swap.pass.cpp
@@ -18,7 +18,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::stringbuf buf1("testing");
@@ -62,4 +62,6 @@ int main()
         assert(buf.str() == L"testing");
         assert(buf1.str() == L"");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.cons/default.pass.cpp b/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.cons/default.pass.cpp
index 2121a7a842e427a03227bd2e631dca532a7c248c..836509f2fddbfb03f7ec5feba21592e86bb7fe48 100644
--- a/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.cons/default.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.cons/default.pass.cpp
@@ -31,7 +31,7 @@ struct testbuf
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::stringbuf buf;
@@ -49,4 +49,6 @@ int main()
         testbuf<wchar_t> buf;
         buf.check();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.cons/move.pass.cpp b/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.cons/move.pass.cpp
index 70eff73849213b12452f8d9b3e29a56499ee1a49..a3cccd39c87d277d6ad04d4dcb4496271e818839 100644
--- a/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.cons/move.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.cons/move.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::stringbuf buf1("testing");
@@ -48,4 +48,6 @@ int main()
         std::wstringbuf buf(move(buf1));
         assert(buf.str() == L"testing");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.cons/string.pass.cpp b/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.cons/string.pass.cpp
index 607d314255b62a1f7ad076157e740e38e104b4ab..de211c80ea1be4f35e701bb937271846458174fd 100644
--- a/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.cons/string.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.cons/string.pass.cpp
@@ -17,7 +17,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::stringbuf buf("testing");
@@ -43,4 +43,6 @@ int main()
         std::wstringbuf buf(L"testing", std::ios_base::out);
         assert(buf.str() == L"testing");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.members/str.pass.cpp b/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.members/str.pass.cpp
index baf406b696cfdc6a938cdcbbbab50f7c9218f094..78b572454a5d3c020d91b243c6ec95ca2cc95b5e 100644
--- a/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.members/str.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.members/str.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::stringbuf buf("testing");
@@ -30,4 +30,6 @@ int main()
         buf.str(L"another test");
         assert(buf.str() == L"another test");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.virtuals/overflow.pass.cpp b/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.virtuals/overflow.pass.cpp
index 0f833070525d4f7bf198ae443f5145abbaa33ac5..c9fdd0abcc9d1a56816e378af137f6c55dbe3150 100644
--- a/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.virtuals/overflow.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.virtuals/overflow.pass.cpp
@@ -34,7 +34,7 @@ struct testbuf
     void pbump(int n) {base::pbump(n);}
 };
 
-int main()
+int main(int, char**)
 {
     {  // sanity check
     testbuf<char> tb("");
@@ -97,4 +97,6 @@ int main()
         assert(sb.sputc('2') == '2');
         assert(sb.str() == "abc12");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.virtuals/pbackfail.pass.cpp b/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.virtuals/pbackfail.pass.cpp
index dfbe2084b9ddf987918b44a0b896cefbf0350339..458e393c8ec363f311c6023558ffa615b1d33c94 100644
--- a/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.virtuals/pbackfail.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.virtuals/pbackfail.pass.cpp
@@ -32,7 +32,7 @@ struct testbuf
     void pbump(int n) {base::pbump(n);}
 };
 
-int main()
+int main(int, char**)
 {
     {  // sanity check
     testbuf<char> tb("");
@@ -92,4 +92,6 @@ int main()
         assert(sb.pbackfail(std::char_traits<wchar_t>::eof()) == std::char_traits<wchar_t>::eof());
         assert(sb.str() == L"133");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.virtuals/seekoff.pass.cpp b/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.virtuals/seekoff.pass.cpp
index dbe117eaa173392b4dd0d4639ed8f5fa7ada98bb..1bee5c216a52312f5ac02b524b6e707fb8366f98 100644
--- a/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.virtuals/seekoff.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.virtuals/seekoff.pass.cpp
@@ -17,7 +17,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::stringbuf sb(std::ios_base::in);
@@ -163,4 +163,6 @@ int main()
         assert(sb.sputc(L'c') == L'c');
         assert(sb.str() == L"0123456c89");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.virtuals/seekpos.pass.cpp b/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.virtuals/seekpos.pass.cpp
index 7d687e070c1b693525d821bc9e647bfdfc51cec0..fde91e74ba035e1d887ae9abb1b0c34a4fae1639 100644
--- a/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.virtuals/seekpos.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.virtuals/seekpos.pass.cpp
@@ -17,7 +17,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::stringbuf sb("0123456789", std::ios_base::in);
@@ -73,4 +73,6 @@ int main()
         assert(sb.sputc(L'3') == L'3');
         assert(sb.str() == L"0123456789");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.virtuals/setbuf.pass.cpp b/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.virtuals/setbuf.pass.cpp
index 99bc75e6c8a3317c09c128cac8c0f6cb76d118de..f833debe39da419e726260c37d828a9e9fc2d8ec 100644
--- a/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.virtuals/setbuf.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.virtuals/setbuf.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::stringbuf sb("0123456789");
@@ -28,4 +28,6 @@ int main()
         assert(sb.pubsetbuf(0, 0) == &sb);
         assert(sb.str() == L"0123456789");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.virtuals/underflow.pass.cpp b/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.virtuals/underflow.pass.cpp
index c32449857494be20d9a9a13d033077f012444a02..23b77d229ca804750e84fb6aa5f2313254e43a97 100644
--- a/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.virtuals/underflow.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/stringbuf/stringbuf.virtuals/underflow.pass.cpp
@@ -28,7 +28,7 @@ struct testbuf
     void pbump(int n) {base::pbump(n);}
 };
 
-int main()
+int main(int, char**)
 {
     {
         testbuf<char> sb("123");
@@ -66,4 +66,6 @@ int main()
         assert(sb.underflow() == L'4');
         assert(sb.underflow() == L'4');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/stringbuf/types.pass.cpp b/libcxx/test/std/input.output/string.streams/stringbuf/types.pass.cpp
index 29d651fc5e549ff9a125f5666a81b32b42a1f548..c27db8535991b7cb039941b3156c5832ed814a37 100644
--- a/libcxx/test/std/input.output/string.streams/stringbuf/types.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/stringbuf/types.pass.cpp
@@ -23,7 +23,7 @@
 #include <sstream>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::basic_streambuf<char>, std::basic_stringbuf<char> >::value), "");
     static_assert((std::is_same<std::basic_stringbuf<char>::char_type, char>::value), "");
@@ -32,4 +32,6 @@ int main()
     static_assert((std::is_same<std::basic_stringbuf<char>::pos_type, std::char_traits<char>::pos_type>::value), "");
     static_assert((std::is_same<std::basic_stringbuf<char>::off_type, std::char_traits<char>::off_type>::value), "");
     static_assert((std::is_same<std::basic_stringbuf<char>::allocator_type, std::allocator<char> >::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/stringstream.cons/default.pass.cpp b/libcxx/test/std/input.output/string.streams/stringstream.cons/default.pass.cpp
index 571c3dc658ed56106e5775da1eb41ce3418e2234..11cf288fcc9f10a92a426f7634d1b875c2452ba0 100644
--- a/libcxx/test/std/input.output/string.streams/stringstream.cons/default.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/stringstream.cons/default.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::stringstream ss;
@@ -42,4 +42,6 @@ int main()
         assert(ss.good());
         assert(ss.str() == L"");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/stringstream.cons/move.pass.cpp b/libcxx/test/std/input.output/string.streams/stringstream.cons/move.pass.cpp
index 671aee553978aa14c0b9b9530d14c8d20f1ba9d3..2a73ad9c2157f9900419951068dd3036d475e634 100644
--- a/libcxx/test/std/input.output/string.streams/stringstream.cons/move.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/stringstream.cons/move.pass.cpp
@@ -18,7 +18,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::stringstream ss0(" 123 456 ");
@@ -48,4 +48,6 @@ int main()
         ss << i << ' ' << 123;
         assert(ss.str() == L"456 1236 ");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/stringstream.cons/move2.pass.cpp b/libcxx/test/std/input.output/string.streams/stringstream.cons/move2.pass.cpp
index 4527cae33f62a7e132be67089745696334b136ad..044e62824ca2c66106767273c4c2bd99c0082685 100644
--- a/libcxx/test/std/input.output/string.streams/stringstream.cons/move2.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/stringstream.cons/move2.pass.cpp
@@ -21,7 +21,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     std::vector<std::istringstream> vecis;
     vecis.push_back(std::istringstream());
@@ -34,4 +34,6 @@ int main()
         vecis[n].seekg(0, std::ios_base::beg);
         assert(vecis[n].str().size() == 31);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/stringstream.cons/string.pass.cpp b/libcxx/test/std/input.output/string.streams/stringstream.cons/string.pass.cpp
index 7bc383f9a4a6e670dfc011f8beed218cbf531c99..29c81b3be62720adffdd769f78a7997705f2ac4b 100644
--- a/libcxx/test/std/input.output/string.streams/stringstream.cons/string.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/stringstream.cons/string.pass.cpp
@@ -27,7 +27,7 @@ struct NoDefaultAllocator : std::allocator<T>
 };
 
 
-int main()
+int main(int, char**)
 {
     {
         std::stringstream ss(" 123 456 ");
@@ -64,4 +64,6 @@ int main()
     //  This test is not required by the standard, but *where else* could it get the allocator?
         assert(sb.str().get_allocator() == s.get_allocator());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/stringstream.cons/stringstream.assign/member_swap.pass.cpp b/libcxx/test/std/input.output/string.streams/stringstream.cons/stringstream.assign/member_swap.pass.cpp
index 07d3a1dea9d8b5c63695256fa6bd20b95ff78c27..2e0f4471a1caf8e5c2774cc5890f8be64bdc9929 100644
--- a/libcxx/test/std/input.output/string.streams/stringstream.cons/stringstream.assign/member_swap.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/stringstream.cons/stringstream.assign/member_swap.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::stringstream ss0(" 123 456 ");
@@ -52,4 +52,6 @@ int main()
         ss0 << i << ' ' << 123;
         assert(ss0.str() == L"456 123");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/stringstream.cons/stringstream.assign/move.pass.cpp b/libcxx/test/std/input.output/string.streams/stringstream.cons/stringstream.assign/move.pass.cpp
index 0332924a69f05eefaadc4b2079cd65e87e3b01e2..c3088679ed6425bab6a7d7fd66ffde8560a12de2 100644
--- a/libcxx/test/std/input.output/string.streams/stringstream.cons/stringstream.assign/move.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/stringstream.cons/stringstream.assign/move.pass.cpp
@@ -18,7 +18,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::stringstream ss0(" 123 456 ");
@@ -50,4 +50,6 @@ int main()
         ss << i << ' ' << 123;
         assert(ss.str() == L"456 1236 ");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/stringstream.cons/stringstream.assign/nonmember_swap.pass.cpp b/libcxx/test/std/input.output/string.streams/stringstream.cons/stringstream.assign/nonmember_swap.pass.cpp
index 3225b273e682d10b489a14ff3ffdd5bf88c4a610..06a95dcb394151986ed995d35906b8468e8c0570 100644
--- a/libcxx/test/std/input.output/string.streams/stringstream.cons/stringstream.assign/nonmember_swap.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/stringstream.cons/stringstream.assign/nonmember_swap.pass.cpp
@@ -19,7 +19,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::stringstream ss0(" 123 456 ");
@@ -55,4 +55,6 @@ int main()
         ss0 << i << ' ' << 123;
         assert(ss0.str() == L"456 123");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/stringstream.members/str.pass.cpp b/libcxx/test/std/input.output/string.streams/stringstream.members/str.pass.cpp
index 392a1680e5c16d5dc924a31b9025a45e79a7e6c1..1dc655193b8ecb2027b9071898386a42812ecd6c 100644
--- a/libcxx/test/std/input.output/string.streams/stringstream.members/str.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/stringstream.members/str.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::stringstream ss(" 123 456 ");
@@ -63,4 +63,6 @@ int main()
         ss.write("\xd1", 1);
         assert(ss.str().length() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/input.output/string.streams/stringstream/types.pass.cpp b/libcxx/test/std/input.output/string.streams/stringstream/types.pass.cpp
index e05048a2df1547ec5206e63f3a9a6fa556ce8beb..580ccb9a4e6e1f1808f3df2a62f5eef9a8f9ab3e 100644
--- a/libcxx/test/std/input.output/string.streams/stringstream/types.pass.cpp
+++ b/libcxx/test/std/input.output/string.streams/stringstream/types.pass.cpp
@@ -23,7 +23,7 @@
 #include <sstream>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::basic_iostream<char>, std::basic_stringstream<char> >::value), "");
     static_assert((std::is_same<std::basic_stringstream<char>::char_type, char>::value), "");
@@ -32,4 +32,6 @@ int main()
     static_assert((std::is_same<std::basic_stringstream<char>::pos_type, std::char_traits<char>::pos_type>::value), "");
     static_assert((std::is_same<std::basic_stringstream<char>::off_type, std::char_traits<char>::off_type>::value), "");
     static_assert((std::is_same<std::basic_stringstream<char>::allocator_type, std::allocator<char> >::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.container/data.pass.cpp b/libcxx/test/std/iterators/iterator.container/data.pass.cpp
index ab80c1cf5ca8789fa8ca72c47f089a6136cf619a..952dc687083d0125ef98f475f670f1b874448fdd 100644
--- a/libcxx/test/std/iterators/iterator.container/data.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.container/data.pass.cpp
@@ -61,7 +61,7 @@ void test_const_array( const T (&array)[Sz] )
     assert ( std::data(array) == &array[0]);
 }
 
-int main()
+int main(int, char**)
 {
     std::vector<int> v; v.push_back(1);
     std::array<int, 1> a; a[0] = 3;
@@ -83,4 +83,6 @@ int main()
 
     static constexpr int arrA [] { 1, 2, 3 };
     test_const_array ( arrA );
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.container/empty.array.fail.cpp b/libcxx/test/std/iterators/iterator.container/empty.array.fail.cpp
index 1cd16ad9a378f65e55bc9f573010dc9f7164605c..08014776c9df300af0b459c5f502cb1d5747e98b 100644
--- a/libcxx/test/std/iterators/iterator.container/empty.array.fail.cpp
+++ b/libcxx/test/std/iterators/iterator.container/empty.array.fail.cpp
@@ -20,8 +20,10 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     int c[5];
     std::empty(c);  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.container/empty.container.fail.cpp b/libcxx/test/std/iterators/iterator.container/empty.container.fail.cpp
index 4ac2e1335ce4d9703b0d25fae7698b914b0905a3..153ea13b643e120dcc1ce1d9ddd391df3b043464 100644
--- a/libcxx/test/std/iterators/iterator.container/empty.container.fail.cpp
+++ b/libcxx/test/std/iterators/iterator.container/empty.container.fail.cpp
@@ -20,8 +20,10 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     std::vector<int> c;
     std::empty(c);  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.container/empty.initializer_list.fail.cpp b/libcxx/test/std/iterators/iterator.container/empty.initializer_list.fail.cpp
index dcdd89a31359562f3cc963bf460cbef97e3872a1..5dafb5119fe911115a25f480d00cbcca237048f3 100644
--- a/libcxx/test/std/iterators/iterator.container/empty.initializer_list.fail.cpp
+++ b/libcxx/test/std/iterators/iterator.container/empty.initializer_list.fail.cpp
@@ -20,8 +20,10 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     std::initializer_list<int> c = { 4 };
     std::empty(c);  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.container/empty.pass.cpp b/libcxx/test/std/iterators/iterator.container/empty.pass.cpp
index b792e0066587e9ee4c6bdb696ea52a135c07c6cc..5c46cd6fbf0279905e7b6cd5e0bc61ac35ac56d9 100644
--- a/libcxx/test/std/iterators/iterator.container/empty.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.container/empty.pass.cpp
@@ -60,7 +60,7 @@ void test_const_array( const T (&array)[Sz] )
     assert (!std::empty(array));
 }
 
-int main()
+int main(int, char**)
 {
     std::vector<int> v; v.push_back(1);
     std::list<int>   l; l.push_back(2);
@@ -85,4 +85,6 @@ int main()
 
     static constexpr int arrA [] { 1, 2, 3 };
     test_const_array ( arrA );
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.container/size.pass.cpp b/libcxx/test/std/iterators/iterator.container/size.pass.cpp
index 5b78afa26698625d89e7839601a74b802288de6f..db215b8544fef7140c5222b1cd6500606aceb3ac 100644
--- a/libcxx/test/std/iterators/iterator.container/size.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.container/size.pass.cpp
@@ -63,7 +63,7 @@ void test_const_array( const T (&array)[Sz] )
     assert ( std::size(array) == Sz );
 }
 
-int main()
+int main(int, char**)
 {
     std::vector<int> v; v.push_back(1);
     std::list<int>   l; l.push_back(2);
@@ -87,4 +87,6 @@ int main()
 
     static constexpr int arrA [] { 1, 2, 3 };
     test_const_array ( arrA );
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.primitives/iterator.basic/iterator.pass.cpp b/libcxx/test/std/iterators/iterator.primitives/iterator.basic/iterator.pass.cpp
index e922a4bfa466abb0d5a7d5354643b84809259eff..b5929ca8c10592b6df7b182bee5ec9254fd75bd4 100644
--- a/libcxx/test/std/iterators/iterator.primitives/iterator.basic/iterator.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.primitives/iterator.basic/iterator.pass.cpp
@@ -72,10 +72,12 @@ test5()
     static_assert((std::is_same<typename It::iterator_category, std::input_iterator_tag>::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     test2<A>();
     test3<A>();
     test4<A>();
     test5<A>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.primitives/iterator.operations/advance.pass.cpp b/libcxx/test/std/iterators/iterator.primitives/iterator.operations/advance.pass.cpp
index 6382d06c74bb41057fc7672bf62f0476a3ed3daf..454080563708b2b505f9374c05f437dafe971080 100644
--- a/libcxx/test/std/iterators/iterator.primitives/iterator.operations/advance.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.primitives/iterator.operations/advance.pass.cpp
@@ -42,7 +42,7 @@ constepxr_test(It i, typename std::iterator_traits<It>::difference_type n, It x)
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
     const char* s = "1234567890";
@@ -68,4 +68,6 @@ int main()
     static_assert( constepxr_test(s+5, -5, s), "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.primitives/iterator.operations/distance.pass.cpp b/libcxx/test/std/iterators/iterator.primitives/iterator.operations/distance.pass.cpp
index 86fcfbc5853d5f601fc877c21a61bd91e788684e..bd1b02a484df7e5a1fdfe36797754080f6ebba48 100644
--- a/libcxx/test/std/iterators/iterator.primitives/iterator.operations/distance.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.primitives/iterator.operations/distance.pass.cpp
@@ -37,7 +37,7 @@ constexpr_test(It first, It last, typename std::iterator_traits<It>::difference_
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
     const char* s = "1234567890";
@@ -57,4 +57,6 @@ int main()
     static_assert( constexpr_test(s, s+10, 10), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.primitives/iterator.operations/next.pass.cpp b/libcxx/test/std/iterators/iterator.primitives/iterator.operations/next.pass.cpp
index ad99aed99b59c07da2c137b3ea83846fbfbb1889..87f79fbd32bea05ff21bc5fff614df3ea088358b 100644
--- a/libcxx/test/std/iterators/iterator.primitives/iterator.operations/next.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.primitives/iterator.operations/next.pass.cpp
@@ -51,7 +51,7 @@ constexpr_test(It i, It x)
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
     const char* s = "1234567890";
@@ -83,4 +83,6 @@ int main()
     static_assert( constexpr_test(s, s+1), "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.primitives/iterator.operations/prev.pass.cpp b/libcxx/test/std/iterators/iterator.primitives/iterator.operations/prev.pass.cpp
index b7d99391723c63d981d0b3f36877ff51f4efc53a..2ee0444ce14b43a90518bfc11cea2e6e7dee7a45 100644
--- a/libcxx/test/std/iterators/iterator.primitives/iterator.operations/prev.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.primitives/iterator.operations/prev.pass.cpp
@@ -49,7 +49,7 @@ constexpr_test(It i, It x)
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
     const char* s = "1234567890";
@@ -74,4 +74,6 @@ int main()
     }
 #endif
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.primitives/iterator.traits/const_pointer.pass.cpp b/libcxx/test/std/iterators/iterator.primitives/iterator.traits/const_pointer.pass.cpp
index 246aeb5e8bb67eae16cd5b1ca3cb2a75e0723469..5abf59bf3dea689fb361b85fe057630041910b45 100644
--- a/libcxx/test/std/iterators/iterator.primitives/iterator.traits/const_pointer.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.primitives/iterator.traits/const_pointer.pass.cpp
@@ -23,7 +23,7 @@
 
 struct A {};
 
-int main()
+int main(int, char**)
 {
     typedef std::iterator_traits<const A*> It;
     static_assert((std::is_same<It::difference_type, std::ptrdiff_t>::value), "");
@@ -31,4 +31,6 @@ int main()
     static_assert((std::is_same<It::pointer, const A*>::value), "");
     static_assert((std::is_same<It::reference, const A&>::value), "");
     static_assert((std::is_same<It::iterator_category, std::random_access_iterator_tag>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.primitives/iterator.traits/const_volatile_pointer.pass.cpp b/libcxx/test/std/iterators/iterator.primitives/iterator.traits/const_volatile_pointer.pass.cpp
index 774609e1cc1ede4a1f7dc122de83d2e9d6884386..358abb619b1402d9d03fe12402f73a83911948ef 100644
--- a/libcxx/test/std/iterators/iterator.primitives/iterator.traits/const_volatile_pointer.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.primitives/iterator.traits/const_volatile_pointer.pass.cpp
@@ -16,7 +16,7 @@
 
 struct A {};
 
-int main()
+int main(int, char**)
 {
     typedef std::iterator_traits<const volatile A*> It;
     static_assert((std::is_same<It::difference_type, std::ptrdiff_t>::value), "");
@@ -24,4 +24,6 @@ int main()
     static_assert((std::is_same<It::pointer, const volatile A*>::value), "");
     static_assert((std::is_same<It::reference, const volatile A&>::value), "");
     static_assert((std::is_same<It::iterator_category, std::random_access_iterator_tag>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.primitives/iterator.traits/empty.fail.cpp b/libcxx/test/std/iterators/iterator.primitives/iterator.traits/empty.fail.cpp
index 5c5c07d442da8e0d94e684d00d5cff4413494bf9..728909e693cc6c31b9a4bddcfc6aaf02695a8590 100644
--- a/libcxx/test/std/iterators/iterator.primitives/iterator.traits/empty.fail.cpp
+++ b/libcxx/test/std/iterators/iterator.primitives/iterator.traits/empty.fail.cpp
@@ -63,7 +63,7 @@ struct NotAnIteratorNoCategory
 //     typedef std::forward_iterator_tag iterator_category;
 };
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::iterator_traits<NotAnIteratorEmpty> T;
@@ -118,4 +118,6 @@ int main()
     typedef T::reference         RT; // expected-error-re {{no type named 'reference' in 'std::{{.+}}::iterator_traits<{{.+}}>}}
     typedef T::iterator_category CT; // expected-error-re {{no type named 'iterator_category' in 'std::{{.+}}::iterator_traits<{{.+}}>}}
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.primitives/iterator.traits/empty.pass.cpp b/libcxx/test/std/iterators/iterator.primitives/iterator.traits/empty.pass.cpp
index 81dca5186eccdd745a92183aa4890070f95841c1..35fc877f2067c498811511851dc3963781b642b7 100644
--- a/libcxx/test/std/iterators/iterator.primitives/iterator.traits/empty.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.primitives/iterator.traits/empty.pass.cpp
@@ -30,8 +30,10 @@ public:
     static const bool value = sizeof(test<T>(0)) == 1;
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::iterator_traits<not_an_iterator> It;
     static_assert(!(has_value_type<It>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.primitives/iterator.traits/iterator.pass.cpp b/libcxx/test/std/iterators/iterator.primitives/iterator.traits/iterator.pass.cpp
index 1c8d11eb1510647a580d210363899cecb1e2cb10..1e4d87c757ccbde150545d58a1f8f7ce61e3b242 100644
--- a/libcxx/test/std/iterators/iterator.primitives/iterator.traits/iterator.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.primitives/iterator.traits/iterator.pass.cpp
@@ -32,7 +32,7 @@ struct test_iterator
     typedef std::forward_iterator_tag iterator_category;
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::iterator_traits<test_iterator> It;
     static_assert((std::is_same<It::difference_type, int>::value), "");
@@ -40,4 +40,6 @@ int main()
     static_assert((std::is_same<It::pointer, A*>::value), "");
     static_assert((std::is_same<It::reference, A&>::value), "");
     static_assert((std::is_same<It::iterator_category, std::forward_iterator_tag>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.primitives/iterator.traits/pointer.pass.cpp b/libcxx/test/std/iterators/iterator.primitives/iterator.traits/pointer.pass.cpp
index 3be21c49a3b0927d86a0aed70f81ef5d36ef0c1c..6016f6d408815c71e1b693a6e99b55f3e1f0ba49 100644
--- a/libcxx/test/std/iterators/iterator.primitives/iterator.traits/pointer.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.primitives/iterator.traits/pointer.pass.cpp
@@ -23,7 +23,7 @@
 
 struct A {};
 
-int main()
+int main(int, char**)
 {
     typedef std::iterator_traits<A*> It;
     static_assert((std::is_same<It::difference_type, std::ptrdiff_t>::value), "");
@@ -31,4 +31,6 @@ int main()
     static_assert((std::is_same<It::pointer, A*>::value), "");
     static_assert((std::is_same<It::reference, A&>::value), "");
     static_assert((std::is_same<It::iterator_category, std::random_access_iterator_tag>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.primitives/iterator.traits/volatile_pointer.pass.cpp b/libcxx/test/std/iterators/iterator.primitives/iterator.traits/volatile_pointer.pass.cpp
index ebcc30075af275572e92b14df6d3f16d7701ecb7..035360645dc6b18d2696983f40e32eb2102bc660 100644
--- a/libcxx/test/std/iterators/iterator.primitives/iterator.traits/volatile_pointer.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.primitives/iterator.traits/volatile_pointer.pass.cpp
@@ -16,7 +16,7 @@
 
 struct A {};
 
-int main()
+int main(int, char**)
 {
     typedef std::iterator_traits<volatile A*> It;
     static_assert((std::is_same<It::difference_type, std::ptrdiff_t>::value), "");
@@ -24,4 +24,6 @@ int main()
     static_assert((std::is_same<It::pointer, volatile A*>::value), "");
     static_assert((std::is_same<It::reference, volatile A&>::value), "");
     static_assert((std::is_same<It::iterator_category, std::random_access_iterator_tag>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.primitives/nothing_to_do.pass.cpp b/libcxx/test/std/iterators/iterator.primitives/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/iterators/iterator.primitives/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.primitives/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.primitives/std.iterator.tags/bidirectional_iterator_tag.pass.cpp b/libcxx/test/std/iterators/iterator.primitives/std.iterator.tags/bidirectional_iterator_tag.pass.cpp
index 6d7f64b9a1ed94172b05fd2f94ce34299efa9835..8380fb6b4e2c998591b7509eae7bb0fa51daf404 100644
--- a/libcxx/test/std/iterators/iterator.primitives/std.iterator.tags/bidirectional_iterator_tag.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.primitives/std.iterator.tags/bidirectional_iterator_tag.pass.cpp
@@ -13,7 +13,7 @@
 #include <iterator>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     std::bidirectional_iterator_tag tag;
     ((void)tag); // Prevent unused warning
@@ -21,4 +21,6 @@ int main()
                                    std::bidirectional_iterator_tag>::value), "");
     static_assert((!std::is_base_of<std::output_iterator_tag,
                                     std::bidirectional_iterator_tag>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.primitives/std.iterator.tags/forward_iterator_tag.pass.cpp b/libcxx/test/std/iterators/iterator.primitives/std.iterator.tags/forward_iterator_tag.pass.cpp
index 753f25c667bfe47fadcb7458bd928a46bb308870..0afdc3eca0a144b4623f4d7cf6f80938af93ccd0 100644
--- a/libcxx/test/std/iterators/iterator.primitives/std.iterator.tags/forward_iterator_tag.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.primitives/std.iterator.tags/forward_iterator_tag.pass.cpp
@@ -13,7 +13,7 @@
 #include <iterator>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     std::forward_iterator_tag tag;
     ((void)tag); // Prevent unused warning
@@ -21,4 +21,6 @@ int main()
                                    std::forward_iterator_tag>::value), "");
     static_assert((!std::is_base_of<std::output_iterator_tag,
                                     std::forward_iterator_tag>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.primitives/std.iterator.tags/input_iterator_tag.pass.cpp b/libcxx/test/std/iterators/iterator.primitives/std.iterator.tags/input_iterator_tag.pass.cpp
index ac517dd6785342bd05c937baa7d7ceb08e344c89..26de37448d108154f95bd11c9b3319230b6932cb 100644
--- a/libcxx/test/std/iterators/iterator.primitives/std.iterator.tags/input_iterator_tag.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.primitives/std.iterator.tags/input_iterator_tag.pass.cpp
@@ -13,10 +13,12 @@
 #include <iterator>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     std::input_iterator_tag tag;
     ((void)tag); // Prevent unused warning
     static_assert((!std::is_base_of<std::output_iterator_tag,
                                     std::input_iterator_tag>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.primitives/std.iterator.tags/output_iterator_tag.pass.cpp b/libcxx/test/std/iterators/iterator.primitives/std.iterator.tags/output_iterator_tag.pass.cpp
index 1635850cf59b8db47d5ad52ad63616386a78e66a..657e6f8ea184766cc70fae729644d1476127949c 100644
--- a/libcxx/test/std/iterators/iterator.primitives/std.iterator.tags/output_iterator_tag.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.primitives/std.iterator.tags/output_iterator_tag.pass.cpp
@@ -13,10 +13,12 @@
 #include <iterator>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     std::output_iterator_tag tag;
     ((void)tag); // Prevent unused warning
     static_assert((!std::is_base_of<std::input_iterator_tag,
                                     std::output_iterator_tag>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.primitives/std.iterator.tags/random_access_iterator_tag.pass.cpp b/libcxx/test/std/iterators/iterator.primitives/std.iterator.tags/random_access_iterator_tag.pass.cpp
index da2de46817645f37355814f8a94ad768d0e42ccb..5448a6715738d42404885998cbb8c05836ce700c 100644
--- a/libcxx/test/std/iterators/iterator.primitives/std.iterator.tags/random_access_iterator_tag.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.primitives/std.iterator.tags/random_access_iterator_tag.pass.cpp
@@ -13,7 +13,7 @@
 #include <iterator>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     std::random_access_iterator_tag tag;
     ((void)tag); // Prevent unused warning
@@ -21,4 +21,6 @@ int main()
                                    std::random_access_iterator_tag>::value), "");
     static_assert((!std::is_base_of<std::output_iterator_tag,
                                     std::random_access_iterator_tag>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.range/begin-end.fail.cpp b/libcxx/test/std/iterators/iterator.range/begin-end.fail.cpp
index b87b82f272e975bfc6aa433a6df201ee00a7426e..69a2784347475bcb0da45d9a88ea2584ab717eef 100644
--- a/libcxx/test/std/iterators/iterator.range/begin-end.fail.cpp
+++ b/libcxx/test/std/iterators/iterator.range/begin-end.fail.cpp
@@ -40,11 +40,13 @@ namespace Foo {
 }
 
 
-int main(){
+int main(int, char**) {
 // Bug #28927 - shouldn't find these via ADL
     TEST_IGNORE_NODISCARD  std::cbegin (Foo::FakeContainer());
     TEST_IGNORE_NODISCARD  std::cend   (Foo::FakeContainer());
     TEST_IGNORE_NODISCARD  std::crbegin(Foo::FakeContainer());
     TEST_IGNORE_NODISCARD  std::crend  (Foo::FakeContainer());
+
+  return 0;
 }
 #endif
diff --git a/libcxx/test/std/iterators/iterator.range/begin-end.pass.cpp b/libcxx/test/std/iterators/iterator.range/begin-end.pass.cpp
index a55e0b639d30f6c753f0cd8b5a5e197409eecb5b..7580b463dceb828ca9d9c18db1c465b703c5a844 100644
--- a/libcxx/test/std/iterators/iterator.range/begin-end.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.range/begin-end.pass.cpp
@@ -135,7 +135,7 @@ void test_const_array( const T (&array)[Sz] ) {
 #endif
     }
 
-int main(){
+int main(int, char**) {
     std::vector<int> v; v.push_back(1);
     std::list<int> l;   l.push_back(2);
     std::array<int, 1> a; a[0] = 3;
@@ -197,4 +197,6 @@ int main(){
         static_assert ( *std::crbegin(c) == 4, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.requirements/bidirectional.iterators/nothing_to_do.pass.cpp b/libcxx/test/std/iterators/iterator.requirements/bidirectional.iterators/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/iterators/iterator.requirements/bidirectional.iterators/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.requirements/bidirectional.iterators/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.requirements/forward.iterators/nothing_to_do.pass.cpp b/libcxx/test/std/iterators/iterator.requirements/forward.iterators/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/iterators/iterator.requirements/forward.iterators/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.requirements/forward.iterators/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.requirements/input.iterators/nothing_to_do.pass.cpp b/libcxx/test/std/iterators/iterator.requirements/input.iterators/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/iterators/iterator.requirements/input.iterators/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.requirements/input.iterators/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.requirements/iterator.iterators/nothing_to_do.pass.cpp b/libcxx/test/std/iterators/iterator.requirements/iterator.iterators/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/iterators/iterator.requirements/iterator.iterators/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.requirements/iterator.iterators/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.requirements/iterator.requirements.general/nothing_to_do.pass.cpp b/libcxx/test/std/iterators/iterator.requirements/iterator.requirements.general/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/iterators/iterator.requirements/iterator.requirements.general/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.requirements/iterator.requirements.general/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.requirements/nothing_to_do.pass.cpp b/libcxx/test/std/iterators/iterator.requirements/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/iterators/iterator.requirements/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.requirements/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.requirements/output.iterators/nothing_to_do.pass.cpp b/libcxx/test/std/iterators/iterator.requirements/output.iterators/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/iterators/iterator.requirements/output.iterators/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.requirements/output.iterators/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.requirements/random.access.iterators/nothing_to_do.pass.cpp b/libcxx/test/std/iterators/iterator.requirements/random.access.iterators/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/iterators/iterator.requirements/random.access.iterators/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.requirements/random.access.iterators/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterator.synopsis/nothing_to_do.pass.cpp b/libcxx/test/std/iterators/iterator.synopsis/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/iterators/iterator.synopsis/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/iterators/iterator.synopsis/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/iterators.general/gcc_workaround.pass.cpp b/libcxx/test/std/iterators/iterators.general/gcc_workaround.pass.cpp
index a6be18d10ec400707dfc2ed902335bd755da685c..09b4d76288c5bfbdde37f9cdb0ced1cc7f9d80de 100644
--- a/libcxx/test/std/iterators/iterators.general/gcc_workaround.pass.cpp
+++ b/libcxx/test/std/iterators/iterators.general/gcc_workaround.pass.cpp
@@ -17,4 +17,6 @@ void f(const std::string &s) { TEST_IGNORE_NODISCARD s.begin(); }
 
 void AppendTo(const std::vector<char> &v) { TEST_IGNORE_NODISCARD v.begin(); }
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/std/iterators/iterators.general/nothing_to_do.pass.cpp b/libcxx/test/std/iterators/iterators.general/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/iterators/iterators.general/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/iterators/iterators.general/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.insert.iter.cons/container.fail.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.insert.iter.cons/container.fail.cpp
index 1bdd5ddef2582fd137da261caf074baeaaa6e41b..9aad14992f567e7122f479ad41a720f187608f72 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.insert.iter.cons/container.fail.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.insert.iter.cons/container.fail.cpp
@@ -17,7 +17,9 @@
 #include <iterator>
 #include <vector>
 
-int main()
+int main(int, char**)
 {
     std::back_insert_iterator<std::vector<int> > i = std::vector<int>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.insert.iter.cons/container.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.insert.iter.cons/container.pass.cpp
index 22f16c2eb09f9403041fc040cd68161cb94ab75a..2aad3fa3f48075116fd6964ef0585188613227dd 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.insert.iter.cons/container.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.insert.iter.cons/container.pass.cpp
@@ -23,8 +23,10 @@ test(C c)
     std::back_insert_iterator<C> i(c);
 }
 
-int main()
+int main(int, char**)
 {
     test(std::vector<int>());
     test(nasty_vector<int>());
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.insert.iter.op++/post.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.insert.iter.op++/post.pass.cpp
index ccb22b2bd3d1e091217653ae5d10ee4cf5bdd681..d36b1ce06307860fc8d5a87b39657e18a3fbea47 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.insert.iter.op++/post.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.insert.iter.op++/post.pass.cpp
@@ -28,8 +28,10 @@ test(C c)
     assert(c.back() == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test(std::vector<int>());
     test(nasty_vector<int>());
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.insert.iter.op++/pre.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.insert.iter.op++/pre.pass.cpp
index acb272b4ced4d09a3d68dde6b300d2a02414cda6..512eb1e56b3165e997db3913bef72d4cf2247b03 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.insert.iter.op++/pre.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.insert.iter.op++/pre.pass.cpp
@@ -26,8 +26,10 @@ test(C c)
     assert(&r == &i);
 }
 
-int main()
+int main(int, char**)
 {
     test(std::vector<int>());
     test(nasty_vector<int>());
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.insert.iter.op=/lv_value.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.insert.iter.op=/lv_value.pass.cpp
index 67772dabc5784099cb946b65a78b53403c279fa5..2b76a27148e6cae3bdb8148f1fff20c54cbe5536 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.insert.iter.op=/lv_value.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.insert.iter.op=/lv_value.pass.cpp
@@ -39,7 +39,9 @@ public:
         {return x.data_ == y.data_;}
 };
 
-int main()
+int main(int, char**)
 {
     test(std::vector<Copyable>());
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.insert.iter.op=/rv_value.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.insert.iter.op=/rv_value.pass.cpp
index 93fe8e5fa33dab164f878558879dbedb8ae8323d..506b7b6f0005a01a6f8467690313992f2c376fd1 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.insert.iter.op=/rv_value.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.insert.iter.op=/rv_value.pass.cpp
@@ -31,7 +31,9 @@ test(C c)
     assert(c.back() == typename C::value_type());
 }
 
-int main()
+int main(int, char**)
 {
     test(std::vector<std::unique_ptr<int> >());
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.insert.iter.op_astrk/test.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.insert.iter.op_astrk/test.pass.cpp
index b7f11e0f771fa982fadae0d869450e9eccbd483f..460f723a407b6e667bd06d40077904a13d194337 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.insert.iter.op_astrk/test.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.insert.iter.op_astrk/test.pass.cpp
@@ -26,8 +26,10 @@ test(C c)
     assert(&r == &i);
 }
 
-int main()
+int main(int, char**)
 {
     test(std::vector<int>());
     test(nasty_vector<int>());
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.inserter/test.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.inserter/test.pass.cpp
index 6c27ce826b2cd772c812bba858893ade26fd4f15..bd6df64488aab8f9b58a6672726c46a108976a09 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.inserter/test.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/back.inserter/test.pass.cpp
@@ -27,8 +27,10 @@ test(C c)
     assert(c.back() == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test(std::vector<int>());
     test(nasty_vector<int>());
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/nothing_to_do.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iter.ops/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iterator/types.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iterator/types.pass.cpp
index 47d38438218af9d452589f8fd0a86fd73f59b2a3..470392bc551472e9be78db64befc786d0521166d 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iterator/types.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/back.insert.iterator/types.pass.cpp
@@ -52,7 +52,9 @@ test()
     static_assert((std::is_same<typename R::iterator_category, std::output_iterator_tag>::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     test<std::vector<int> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.insert.iter.cons/container.fail.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.insert.iter.cons/container.fail.cpp
index 1ebfd4d3f14bcf37e76aad2287337a125cba26d1..eb3346b2e7aeabecbca56a6ba7ffdced8c453a3f 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.insert.iter.cons/container.fail.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.insert.iter.cons/container.fail.cpp
@@ -17,7 +17,9 @@
 #include <iterator>
 #include <list>
 
-int main()
+int main(int, char**)
 {
     std::front_insert_iterator<std::list<int> > i = std::list<int>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.insert.iter.cons/container.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.insert.iter.cons/container.pass.cpp
index 80307cb1547ddca0e5ff030aa2b2317c246216f6..2ef4ba87994851f20e5da40bd4c3350ca7f1e4a0 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.insert.iter.cons/container.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.insert.iter.cons/container.pass.cpp
@@ -23,8 +23,10 @@ test(C c)
     std::front_insert_iterator<C> i(c);
 }
 
-int main()
+int main(int, char**)
 {
     test(std::list<int>());
     test(nasty_list<int>());
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.insert.iter.op++/post.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.insert.iter.op++/post.pass.cpp
index 9b642a7d24e14a528887dc5f6bef4307515663ff..7c9b09ffd2aa5ea9b5162658d48504b5e4f321ad 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.insert.iter.op++/post.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.insert.iter.op++/post.pass.cpp
@@ -28,8 +28,10 @@ test(C c)
     assert(c.back() == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test(std::list<int>());
     test(nasty_list<int>());
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.insert.iter.op++/pre.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.insert.iter.op++/pre.pass.cpp
index 7aa1d6da6a7330b5c52a3b5b972cc7ccad1298ab..ea5c024105beabc089b7fa894829b84755297697 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.insert.iter.op++/pre.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.insert.iter.op++/pre.pass.cpp
@@ -26,8 +26,10 @@ test(C c)
     assert(&r == &i);
 }
 
-int main()
+int main(int, char**)
 {
     test(std::list<int>());
     test(nasty_list<int>());
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.insert.iter.op=/lv_value.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.insert.iter.op=/lv_value.pass.cpp
index 555b72d797072467c796b16f296f3e2f1b73c89b..5e1a86d57f0a9de17dd89a24ca217b5ebffeb73c 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.insert.iter.op=/lv_value.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.insert.iter.op=/lv_value.pass.cpp
@@ -39,8 +39,10 @@ public:
         {return x.data_ == y.data_;}
 };
 
-int main()
+int main(int, char**)
 {
     test(std::list<Copyable>());
     test(nasty_list<Copyable>());
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.insert.iter.op=/rv_value.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.insert.iter.op=/rv_value.pass.cpp
index ad032a4dde66b5f8fadb6ebe9694366ddec60e92..450f395d49a8711022b14fe33dcee869313b7746 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.insert.iter.op=/rv_value.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.insert.iter.op=/rv_value.pass.cpp
@@ -29,7 +29,9 @@ test(C c)
     assert(c.front() == typename C::value_type());
 }
 
-int main()
+int main(int, char**)
 {
     test(std::list<std::unique_ptr<int> >());
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.insert.iter.op_astrk/test.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.insert.iter.op_astrk/test.pass.cpp
index bf1bf38ad807b550684969bc269005b696c252d2..3367229b4222063d31d719320c0fddb52b2a37dc 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.insert.iter.op_astrk/test.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.insert.iter.op_astrk/test.pass.cpp
@@ -26,8 +26,10 @@ test(C c)
     assert(&r == &i);
 }
 
-int main()
+int main(int, char**)
 {
     test(std::list<int>());
     test(nasty_list<int>());
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.inserter/test.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.inserter/test.pass.cpp
index f4cc7c984f16e274f1307d772614e62a9dfdae29..b7436778d114754ec3bbdfd6507cdb5a267aa08a 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.inserter/test.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/front.inserter/test.pass.cpp
@@ -27,8 +27,10 @@ test(C c)
     assert(c.front() == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test(std::list<int>());
     test(nasty_list<int>());
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/nothing_to_do.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iter.ops/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iterator/types.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iterator/types.pass.cpp
index c8609efbe410a295491c37f354aa4bdef9b548c8..c65a8e6f68d3a812b16d2e780a5ecbf70763d408 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iterator/types.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/front.insert.iterator/types.pass.cpp
@@ -53,7 +53,9 @@ test()
     static_assert((std::is_same<typename R::iterator_category, std::output_iterator_tag>::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     test<std::vector<int> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/insert.iter.cons/test.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/insert.iter.cons/test.pass.cpp
index ae45c90f34eb571db8797e4b9aa2f6781958e81c..531dac03c9f16cd7cca00495904cfa47bcdc46e0 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/insert.iter.cons/test.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/insert.iter.cons/test.pass.cpp
@@ -23,8 +23,10 @@ test(C c)
     std::insert_iterator<C> i(c, c.begin());
 }
 
-int main()
+int main(int, char**)
 {
     test(std::vector<int>());
     test(nasty_vector<int>());
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/insert.iter.op++/post.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/insert.iter.op++/post.pass.cpp
index 22448fddd613b3fd37162027cef7b5df97169f38..a3148e2e2a4bdf1724e83f819eeac17ff8889953 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/insert.iter.op++/post.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/insert.iter.op++/post.pass.cpp
@@ -28,8 +28,10 @@ test(C c)
     assert(c.back() == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test(std::vector<int>());
     test(nasty_vector<int>());
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/insert.iter.op++/pre.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/insert.iter.op++/pre.pass.cpp
index c9a8d1ef6e1504bd3dae84d8ebbe161d7370bd5c..99c686095002b5f3669c7c38ac43ff84394b7b91 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/insert.iter.op++/pre.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/insert.iter.op++/pre.pass.cpp
@@ -26,8 +26,10 @@ test(C c)
     assert(&r == &i);
 }
 
-int main()
+int main(int, char**)
 {
     test(std::vector<int>());
     test(nasty_vector<int>());
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/insert.iter.op=/lv_value.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/insert.iter.op=/lv_value.pass.cpp
index c639a2da169361b17c110a8d4d6cf821d2325aa8..fe8260b999f6a207696df169eeb98a4fc3c3951b 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/insert.iter.op=/lv_value.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/insert.iter.op=/lv_value.pass.cpp
@@ -43,7 +43,7 @@ insert3at(C& c, typename C::iterator i,
     c.insert(++i, x3);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::vector<int> C;
@@ -81,4 +81,6 @@ int main()
     insert3at(c2, c2.begin()+3, 'a', 'b', 'c');
     test(c1, 3, 'a', 'b', 'c', c2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/insert.iter.op=/rv_value.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/insert.iter.op=/rv_value.pass.cpp
index 671d6bd496b48d55df4a081f4744f01489bcc1c0..7a5addb1ab026c11be185f95d67c2b8881824605 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/insert.iter.op=/rv_value.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/insert.iter.op=/rv_value.pass.cpp
@@ -52,7 +52,7 @@ struct do_nothing
     void operator()(void*) const {}
 };
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::unique_ptr<int, do_nothing> Ptr;
@@ -91,4 +91,6 @@ int main()
     insert3at(c2, c2.begin()+3, Ptr(x+3), Ptr(x+4), Ptr(x+5));
     test(std::move(c1), 3, Ptr(x+3), Ptr(x+4), Ptr(x+5), c2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/insert.iter.op_astrk/test.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/insert.iter.op_astrk/test.pass.cpp
index d531e5fe3ac3b1c74ee11d66386e76bfea854ee2..8ef0383eed27cab468eccdc1cbc74c726ef50416 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/insert.iter.op_astrk/test.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/insert.iter.op_astrk/test.pass.cpp
@@ -26,8 +26,10 @@ test(C c)
     assert(&r == &i);
 }
 
-int main()
+int main(int, char**)
 {
     test(std::vector<int>());
     test(nasty_vector<int>());
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/inserter/test.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/inserter/test.pass.cpp
index 05ede8a522f3f8be57a79eb5b174afa46b794545..e1ee829bce72af5dc85694c7ea25a329605268c8 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/inserter/test.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/inserter/test.pass.cpp
@@ -27,8 +27,10 @@ test(C c)
     assert(c.back() == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test(std::vector<int>());
     test(nasty_vector<int>());
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/nothing_to_do.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iter.ops/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iterator/types.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iterator/types.pass.cpp
index 9d58fc40ccbcd3789ffba15e3cc307ac4729063e..1e199b3051b31d977e66d703e3670c6709a68ce3 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iterator/types.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/insert.iterator/types.pass.cpp
@@ -58,7 +58,9 @@ test()
     static_assert((std::is_same<typename R::iterator_category, std::output_iterator_tag>::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     test<std::vector<int> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/insert.iterators/nothing_to_do.pass.cpp b/libcxx/test/std/iterators/predef.iterators/insert.iterators/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/iterators/predef.iterators/insert.iterators/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/insert.iterators/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.nonmember/make_move_iterator.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.nonmember/make_move_iterator.pass.cpp
index 36dfddd7f02ca77fa45fd8da43b056f80aabe77d..3a9b467e06f579f60a9562f6e8df4002ff117468 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.nonmember/make_move_iterator.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.nonmember/make_move_iterator.pass.cpp
@@ -30,7 +30,7 @@ test(It i)
     assert(std::make_move_iterator(i) == r);
 }
 
-int main()
+int main(int, char**)
 {
     {
     char s[] = "1234567890";
@@ -53,4 +53,6 @@ int main()
     static_assert(iter.base() == p);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.nonmember/minus.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.nonmember/minus.pass.cpp
index 67852259734acb3f02e7f43bbae989886782cab1..e3b881edc9e11dadf3d8d6a0a9ebce97245093e4 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.nonmember/minus.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.nonmember/minus.pass.cpp
@@ -33,7 +33,7 @@ test(It l, It r, typename std::iterator_traits<It>::difference_type x)
     assert(r1 - r2 == x);
 }
 
-int main()
+int main(int, char**)
 {
     char s[] = "1234567890";
     test(random_access_iterator<char*>(s+5), random_access_iterator<char*>(s), 5);
@@ -49,4 +49,6 @@ int main()
     static_assert( it2 - it1 ==  1, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.nonmember/plus.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.nonmember/plus.pass.cpp
index 63c3e8ed5d4da8c9a39428bc87e732f9c407bb08..5e1965e19c270d226a880db05b2ea939d2ba41e2 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.nonmember/plus.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.nonmember/plus.pass.cpp
@@ -31,7 +31,7 @@ test(It i, typename std::iterator_traits<It>::difference_type n, It x)
     assert(rr.base() == x);
 }
 
-int main()
+int main(int, char**)
 {
     char s[] = "1234567890";
     test(random_access_iterator<char*>(s+5), 5, random_access_iterator<char*>(s+10));
@@ -49,4 +49,6 @@ int main()
     static_assert(it2 == it3, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.+/difference_type.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.+/difference_type.pass.cpp
index 95ab190f11ab70e1601f4e7a004816f6560776e5..1e3244e19b984699f660f35698b33f235a7348c6 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.+/difference_type.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.+/difference_type.pass.cpp
@@ -30,7 +30,7 @@ test(It i, typename std::iterator_traits<It>::difference_type n, It x)
     assert(rr.base() == x);
 }
 
-int main()
+int main(int, char**)
 {
     const char* s = "1234567890";
     test(random_access_iterator<const char*>(s+5), 5, random_access_iterator<const char*>(s+10));
@@ -48,4 +48,6 @@ int main()
     static_assert(it2 == it3, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.+=/difference_type.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.+=/difference_type.pass.cpp
index 0af1ff83fbfef4a8169a2829741f655d8c7e8d06..863e06c0e45ced2f4a54777fe70e5a6aee7d3d0d 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.+=/difference_type.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.+=/difference_type.pass.cpp
@@ -31,7 +31,7 @@ test(It i, typename std::iterator_traits<It>::difference_type n, It x)
     assert(&rr == &r);
 }
 
-int main()
+int main(int, char**)
 {
     const char* s = "1234567890";
     test(random_access_iterator<const char*>(s+5), 5, random_access_iterator<const char*>(s+10));
@@ -49,4 +49,6 @@ int main()
     static_assert(it2 == it3, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.-/difference_type.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.-/difference_type.pass.cpp
index ce0cb93cff846a33fffc422733d31c3ab8988eb9..3cf76f5daea143c43b5198d6960226114fbad2a9 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.-/difference_type.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.-/difference_type.pass.cpp
@@ -30,7 +30,7 @@ test(It i, typename std::iterator_traits<It>::difference_type n, It x)
     assert(rr.base() == x);
 }
 
-int main()
+int main(int, char**)
 {
     const char* s = "1234567890";
     test(random_access_iterator<const char*>(s+5), 5, random_access_iterator<const char*>(s));
@@ -48,4 +48,6 @@ int main()
     static_assert(it2 != it3, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.-=/difference_type.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.-=/difference_type.pass.cpp
index f17543335e51f34bd92cf793040f0c69258be4d7..5692f708881a8466e968950df32f67a3dbec73ee 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.-=/difference_type.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.-=/difference_type.pass.cpp
@@ -31,7 +31,7 @@ test(It i, typename std::iterator_traits<It>::difference_type n, It x)
     assert(&rr == &r);
 }
 
-int main()
+int main(int, char**)
 {
     const char* s = "1234567890";
     test(random_access_iterator<const char*>(s+5), 5, random_access_iterator<const char*>(s));
@@ -45,4 +45,6 @@ int main()
     static_assert(it1 == it2, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.comp/op_eq.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.comp/op_eq.pass.cpp
index 1e05a50c7f5a8dd4e8b16bce5e7673fa34e44d39..ecf8f90ea1e9f800a7c37108213eb9b2ca62ea13 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.comp/op_eq.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.comp/op_eq.pass.cpp
@@ -32,7 +32,7 @@ test(It l, It r, bool x)
     assert((r1 == r2) == x);
 }
 
-int main()
+int main(int, char**)
 {
     char s[] = "1234567890";
     test(input_iterator<char*>(s), input_iterator<char*>(s), true);
@@ -58,4 +58,6 @@ int main()
     static_assert(!(it2 == it3), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.comp/op_gt.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.comp/op_gt.pass.cpp
index e58a57b50888a66805bb383ca93c376bbfa66d85..3da38b37666417c6db6d3cc20d828a2510e64a7b 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.comp/op_gt.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.comp/op_gt.pass.cpp
@@ -32,7 +32,7 @@ test(It l, It r, bool x)
     assert((r1 > r2) == x);
 }
 
-int main()
+int main(int, char**)
 {
     char s[] = "1234567890";
     test(random_access_iterator<char*>(s), random_access_iterator<char*>(s), false);
@@ -54,4 +54,6 @@ int main()
     static_assert( (it2 > it3), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.comp/op_gte.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.comp/op_gte.pass.cpp
index e10962f02cfc9a09c509f4b839784f2ca148b33d..dceb4115152528aed8c57653e9dfc5e6cf595a24 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.comp/op_gte.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.comp/op_gte.pass.cpp
@@ -32,7 +32,7 @@ test(It l, It r, bool x)
     assert((r1 >= r2) == x);
 }
 
-int main()
+int main(int, char**)
 {
     char s[] = "1234567890";
     test(random_access_iterator<char*>(s), random_access_iterator<char*>(s), true);
@@ -54,4 +54,6 @@ int main()
     static_assert( (it2 >= it3), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.comp/op_lt.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.comp/op_lt.pass.cpp
index ebe90244e26d4b5af223d7108a06fd6bd2c9909c..675e55f7881db37af6bceb5d4c732e2215abfb38 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.comp/op_lt.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.comp/op_lt.pass.cpp
@@ -32,7 +32,7 @@ test(It l, It r, bool x)
     assert((r1 < r2) == x);
 }
 
-int main()
+int main(int, char**)
 {
     char s[] = "1234567890";
     test(random_access_iterator<char*>(s), random_access_iterator<char*>(s), false);
@@ -54,4 +54,6 @@ int main()
     static_assert(!(it2 < it3), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.comp/op_lte.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.comp/op_lte.pass.cpp
index 72efc481e3facf1a0f91a8abbb16f6d92d529016..a2ac0b7a6f7bb46698215a3fce45115fea0e029f 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.comp/op_lte.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.comp/op_lte.pass.cpp
@@ -32,7 +32,7 @@ test(It l, It r, bool x)
     assert((r1 <= r2) == x);
 }
 
-int main()
+int main(int, char**)
 {
     char s[] = "1234567890";
     test(random_access_iterator<char*>(s), random_access_iterator<char*>(s), true);
@@ -54,4 +54,6 @@ int main()
     static_assert(!(it2 <= it3), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.comp/op_neq.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.comp/op_neq.pass.cpp
index 69695e56bbbc3784f6a99aff0b186b48fff5f692..01a7195d4d6479ce01ae68a8658b637842103664 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.comp/op_neq.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.comp/op_neq.pass.cpp
@@ -32,7 +32,7 @@ test(It l, It r, bool x)
     assert((r1 != r2) == x);
 }
 
-int main()
+int main(int, char**)
 {
     char s[] = "1234567890";
     test(input_iterator<char*>(s), input_iterator<char*>(s), false);
@@ -58,4 +58,6 @@ int main()
     static_assert( (it2 != it3), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.const/convert.fail.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.const/convert.fail.cpp
index 56b99025eebcd4b4d731f8064a7c5ffba3a2535f..b91767b0814fae250a04c179a6825a59959be59a 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.const/convert.fail.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.const/convert.fail.cpp
@@ -29,9 +29,11 @@ test(U u)
 struct base {};
 struct derived {};
 
-int main()
+int main(int, char**)
 {
     derived d;
 
     test<base*>(&d);
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.const/convert.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.const/convert.pass.cpp
index dae13100db2c3815b4ccd12c19ef9ec37baf1141..7f31920f76a9a1b0916857c8f2e8c472fea74327 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.const/convert.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.const/convert.pass.cpp
@@ -34,7 +34,7 @@ test(U u)
 struct Base {};
 struct Derived : Base {};
 
-int main()
+int main(int, char**)
 {
     Derived d;
 
@@ -52,4 +52,6 @@ int main()
     static_assert(it2.base() == p);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.const/default.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.const/default.pass.cpp
index dfd89df807c664e9680526b6c21d168d5715daed..6dfa0d09db902b6f00d49243a5348a18ccde4e4d 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.const/default.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.const/default.pass.cpp
@@ -27,7 +27,7 @@ test()
     (void)r;
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<char*> >();
     test<forward_iterator<char*> >();
@@ -41,4 +41,6 @@ int main()
     (void)it;
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.const/iter.fail.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.const/iter.fail.cpp
index 0b8ea45408907bf0b12382fbfcf584c928030817..28648b8153473b89297ff1c55f4e06db7508fdf5 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.const/iter.fail.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.const/iter.fail.cpp
@@ -23,8 +23,10 @@ test(It i)
     std::move_iterator<It> r = i;
 }
 
-int main()
+int main(int, char**)
 {
     char s[] = "123";
     test(s);
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.const/iter.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.const/iter.pass.cpp
index 5832ecbcf8017579dccb51558c450292ecd1abfd..bed97700e7cbc7900ad88aee3cf15b51f5906d36 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.const/iter.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.const/iter.pass.cpp
@@ -28,7 +28,7 @@ test(It i)
     assert(r.base() == i);
 }
 
-int main()
+int main(int, char**)
 {
     char s[] = "123";
     test(input_iterator<char*>(s));
@@ -44,4 +44,6 @@ int main()
     static_assert(it.base() == p);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.conv/tested_elsewhere.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.conv/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.conv/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.conv/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.decr/post.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.decr/post.pass.cpp
index 0b6db37e1440978ec7f24f578a6804640c1b4775..38d52329721ef875c9f18559ac487c6d810495fd 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.decr/post.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.decr/post.pass.cpp
@@ -30,7 +30,7 @@ test(It i, It x)
     assert(rr.base() == i);
 }
 
-int main()
+int main(int, char**)
 {
     char s[] = "123";
     test(bidirectional_iterator<char*>(s+1), bidirectional_iterator<char*>(s));
@@ -49,4 +49,6 @@ int main()
     static_assert(it2 == it3, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.decr/pre.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.decr/pre.pass.cpp
index c7c00183c7cadeebe034bbae07be260539a77e0b..e98fb6b093649f7ac5d80b6b37c5e85a9fdcb916 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.decr/pre.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.decr/pre.pass.cpp
@@ -30,7 +30,7 @@ test(It i, It x)
     assert(&rr == &r);
 }
 
-int main()
+int main(int, char**)
 {
     char s[] = "123";
     test(bidirectional_iterator<char*>(s+1), bidirectional_iterator<char*>(s));
@@ -49,4 +49,6 @@ int main()
     static_assert(it2 != it3, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.incr/post.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.incr/post.pass.cpp
index f37522c13f63d604d64f171149a96d2e61cb9fc8..50597a54b0bf74c8609cc4e9946b7b758bc047ff 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.incr/post.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.incr/post.pass.cpp
@@ -30,7 +30,7 @@ test(It i, It x)
     assert(rr.base() == i);
 }
 
-int main()
+int main(int, char**)
 {
     char s[] = "123";
     test(input_iterator<char*>(s), input_iterator<char*>(s+1));
@@ -51,4 +51,6 @@ int main()
     static_assert(it2 != it3, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.incr/pre.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.incr/pre.pass.cpp
index 4bcbdd5792b170abce9adec19eb1a59d56ea0b05..101f5cdbc0f41b816f1a197368385494916f4092 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.incr/pre.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.incr/pre.pass.cpp
@@ -30,7 +30,7 @@ test(It i, It x)
     assert(&rr == &r);
 }
 
-int main()
+int main(int, char**)
 {
     char s[] = "123";
     test(input_iterator<char*>(s), input_iterator<char*>(s+1));
@@ -51,4 +51,6 @@ int main()
     static_assert(it2 == it3, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.index/difference_type.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.index/difference_type.pass.cpp
index d626ff28a381895817d32e31639668e33df7317a..ecf3b61058b7f563bad75af6e140038e7040e402 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.index/difference_type.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.index/difference_type.pass.cpp
@@ -38,7 +38,7 @@ struct do_nothing
     void operator()(void*) const {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         char s[] = "1234567890";
@@ -64,4 +64,6 @@ int main()
     static_assert(it1[5] == '6', "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.ref/op_arrow.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.ref/op_arrow.pass.cpp
index 027162b90f0d72791895a793e02b21ca68badd34..6024f99fec3f14af07b5f784fdcd43ff1b06dc7d 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.ref/op_arrow.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.ref/op_arrow.pass.cpp
@@ -27,7 +27,7 @@ test(It i)
     assert(r.operator->() == i);
 }
 
-int main()
+int main(int, char**)
 {
     char s[] = "123";
     test(s);
@@ -42,4 +42,6 @@ int main()
     static_assert(it2.operator->() == p + 1, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.star/op_star.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.star/op_star.pass.cpp
index 6dfe0a51736049428ace7274ca3a87c536a745ba..e6e826d835256eb2b595197e845c289f09e70fb5 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.star/op_star.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.star/op_star.pass.cpp
@@ -47,7 +47,7 @@ struct do_nothing
 };
 
 
-int main()
+int main(int, char**)
 {
     {
         A a;
@@ -70,4 +70,6 @@ int main()
     static_assert(*it2 == p[1], "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op=/move_iterator.fail.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op=/move_iterator.fail.cpp
index 68fe476ac64d746e13b64c50b56eeb3f7e8fbfbc..94d012dfb7e32c04037b1a787853e3363f25f76e 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op=/move_iterator.fail.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op=/move_iterator.fail.cpp
@@ -31,8 +31,10 @@ test(U u)
 struct base {};
 struct derived {};
 
-int main()
+int main(int, char**)
 {
     derived d;
     test<base*>(&d);
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op=/move_iterator.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op=/move_iterator.pass.cpp
index fbc5320feb5c55305cefaa1c1458273ffb39b446..84fbccb8be63c50add39fad9c3edb2f64fb86641 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op=/move_iterator.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op=/move_iterator.pass.cpp
@@ -37,7 +37,7 @@ test(U u)
 struct Base {};
 struct Derived : Base {};
 
-int main()
+int main(int, char**)
 {
     Derived d;
 
@@ -56,4 +56,6 @@ int main()
     static_assert(it2.base() == p, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/nothing_to_do.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.requirements/nothing_to_do.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.requirements/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.requirements/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.requirements/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iterator/types.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iterator/types.pass.cpp
index 9eb4669c3c59cd8eafa7e4e8ba5e4534a02efc38..905952f42bd4dc53f546c031d4ae9fbcd2047d08 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iterator/types.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iterator/types.pass.cpp
@@ -55,7 +55,7 @@ test()
     static_assert((std::is_same<typename R::iterator_category, typename T::iterator_category>::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<char*> >();
     test<forward_iterator<char*> >();
@@ -91,4 +91,6 @@ int main()
         static_assert(std::is_same<It::reference, int&&>::value, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/move.iterators/nothing_to_do.pass.cpp b/libcxx/test/std/iterators/predef.iterators/move.iterators/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/iterators/predef.iterators/move.iterators/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/move.iterators/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/nothing_to_do.pass.cpp b/libcxx/test/std/iterators/predef.iterators/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/iterators/predef.iterators/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/nothing_to_do.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/nothing_to_do.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.cons/default.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.cons/default.pass.cpp
index de035fcd3c9e4b8f16d59a5d5ed651c0d456425d..32931eefa9169df720bd1c3b228de0b97022e927 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.cons/default.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.cons/default.pass.cpp
@@ -27,7 +27,7 @@ test()
     (void)r;
 }
 
-int main()
+int main(int, char**)
 {
     test<bidirectional_iterator<const char*> >();
     test<random_access_iterator<char*> >();
@@ -40,4 +40,6 @@ int main()
         (void)it;
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.cons/iter.fail.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.cons/iter.fail.cpp
index bbbf1247f473d808dbd711f5a09ab13844428799..6130386b0d247c63a403ccec43a6283bc83d88db 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.cons/iter.fail.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.cons/iter.fail.cpp
@@ -23,8 +23,10 @@ test(It i)
     std::reverse_iterator<It> r = i;
 }
 
-int main()
+int main(int, char**)
 {
     const char s[] = "123";
     test(s);
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.cons/iter.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.cons/iter.pass.cpp
index 47fc29b094a785ee8ddd4be3b49d1234a5558625..32cc74f9586a17f74a76a1395b72f1d5e4e16904 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.cons/iter.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.cons/iter.pass.cpp
@@ -28,7 +28,7 @@ test(It i)
     assert(r.base() == i);
 }
 
-int main()
+int main(int, char**)
 {
     const char s[] = "123";
     test(bidirectional_iterator<const char*>(s));
@@ -42,4 +42,6 @@ int main()
         static_assert(it.base() == p);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.cons/reverse_iterator.fail.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.cons/reverse_iterator.fail.cpp
index 02ab54a598698312ca9a6c4e5267fbc0060c8e75..5a878e4937e04a2ee0b5bc6d105864fc1910d236 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.cons/reverse_iterator.fail.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.cons/reverse_iterator.fail.cpp
@@ -29,9 +29,11 @@ test(U u)
 struct base {};
 struct derived {};
 
-int main()
+int main(int, char**)
 {
     derived d;
 
     test<base*>(&d);
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.cons/reverse_iterator.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.cons/reverse_iterator.pass.cpp
index db53853dc5920b235150fb2073a468960caea6fc..53b82bd4038c876035f268ddb6ca1589a7a65b8c 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.cons/reverse_iterator.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.cons/reverse_iterator.pass.cpp
@@ -34,7 +34,7 @@ test(U u)
 struct Base {};
 struct Derived : Base {};
 
-int main()
+int main(int, char**)
 {
     Derived d;
 
@@ -50,4 +50,6 @@ int main()
         static_assert(it2.base() == p);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.conv/tested_elsewhere.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.conv/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.conv/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.conv/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.make/make_reverse_iterator.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.make/make_reverse_iterator.pass.cpp
index 8ad3d79b39027bb0b59a0f3162dca687a5b16f2a..fa7026ddeece64533acc384a282a2df737c274c3 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.make/make_reverse_iterator.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.make/make_reverse_iterator.pass.cpp
@@ -31,7 +31,7 @@ test(It i)
     assert(r.base() == i);
 }
 
-int main()
+int main(int, char**)
 {
     const char* s = "1234567890";
     random_access_iterator<const char*>b(s);
@@ -46,5 +46,7 @@ int main()
         static_assert(it1.base() == p, "");
     }
 #endif
+
+  return 0;
 }
 
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op!=/test.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op!=/test.pass.cpp
index c67884d9187d79a529a800218b747ad1150a3fe3..f3e74970967956ea0731dd5da8c5a082032880de 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op!=/test.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op!=/test.pass.cpp
@@ -32,7 +32,7 @@ test(It l, It r, bool x)
     assert((r1 != r2) == x);
 }
 
-int main()
+int main(int, char**)
 {
     const char* s = "1234567890";
     test(bidirectional_iterator<const char*>(s), bidirectional_iterator<const char*>(s), false);
@@ -53,4 +53,6 @@ int main()
         static_assert( (it1 != it3), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op++/post.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op++/post.pass.cpp
index 2232a87f5c5e664d51a5929e1e8345a1b285dd8d..d7658ccfc991f53c7f114acdf27cd5ccaab5ff71 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op++/post.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op++/post.pass.cpp
@@ -30,7 +30,7 @@ test(It i, It x)
     assert(rr.base() == i);
 }
 
-int main()
+int main(int, char**)
 {
     const char* s = "123";
     test(bidirectional_iterator<const char*>(s+1), bidirectional_iterator<const char*>(s));
@@ -49,4 +49,6 @@ int main()
         static_assert(it2 == it3, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op++/pre.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op++/pre.pass.cpp
index d2337e2086e987ca410376f9bbcbeaa3788224c7..edc74fab504e4711ea9d6ee6969bc8087fbbae38 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op++/pre.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op++/pre.pass.cpp
@@ -30,7 +30,7 @@ test(It i, It x)
     assert(&rr == &r);
 }
 
-int main()
+int main(int, char**)
 {
     const char* s = "123";
     test(bidirectional_iterator<const char*>(s+1), bidirectional_iterator<const char*>(s));
@@ -50,4 +50,6 @@ int main()
         static_assert(*(++std::make_reverse_iterator(p+2)) == '1', "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op+/difference_type.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op+/difference_type.pass.cpp
index eed06f3df9c2466a5e3925c9dd78c387112a1091..9b30f59da934702205c198606dc241c3b785d307 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op+/difference_type.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op+/difference_type.pass.cpp
@@ -30,7 +30,7 @@ test(It i, typename std::iterator_traits<It>::difference_type n, It x)
     assert(rr.base() == x);
 }
 
-int main()
+int main(int, char**)
 {
     const char* s = "1234567890";
     test(random_access_iterator<const char*>(s+5), 5, random_access_iterator<const char*>(s));
@@ -48,4 +48,6 @@ int main()
         static_assert(it2 != it3, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op+=/difference_type.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op+=/difference_type.pass.cpp
index 5460382133c67d253ef638d8f4b3b9a533153169..229f3ca11881203242d823ac10300968a6f965df 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op+=/difference_type.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op+=/difference_type.pass.cpp
@@ -31,7 +31,7 @@ test(It i, typename std::iterator_traits<It>::difference_type n, It x)
     assert(&rr == &r);
 }
 
-int main()
+int main(int, char**)
 {
     const char* s = "1234567890";
     test(random_access_iterator<const char*>(s+5), 5, random_access_iterator<const char*>(s));
@@ -45,4 +45,6 @@ int main()
         static_assert(it1 == it2, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op--/post.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op--/post.pass.cpp
index 35fdf1b1ed826a3aeeb5c1b47cf6fe7d512a9ef0..8b9912c8173431bb9408199f1358905d438fa013 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op--/post.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op--/post.pass.cpp
@@ -30,7 +30,7 @@ test(It i, It x)
     assert(rr.base() == i);
 }
 
-int main()
+int main(int, char**)
 {
     const char* s = "123";
     test(bidirectional_iterator<const char*>(s+1), bidirectional_iterator<const char*>(s+2));
@@ -49,4 +49,6 @@ int main()
         static_assert(it2 != it3, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op--/pre.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op--/pre.pass.cpp
index f0df91777a7f3c637f4119f45e6365e70cee625a..9ccab06e83907ff4ca54f578e5d5e4df1949c238 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op--/pre.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op--/pre.pass.cpp
@@ -30,7 +30,7 @@ test(It i, It x)
     assert(&rr == &r);
 }
 
-int main()
+int main(int, char**)
 {
     const char* s = "123";
     test(bidirectional_iterator<const char*>(s+1), bidirectional_iterator<const char*>(s+2));
@@ -50,4 +50,6 @@ int main()
         static_assert(*(--std::make_reverse_iterator(p)) == '1', "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op-/difference_type.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op-/difference_type.pass.cpp
index b59095db8a4e7a6e20d378ff9cdd8f1a6c8bccae..0e3a5d36210ebec2a017fbffd859fb05757361b4 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op-/difference_type.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op-/difference_type.pass.cpp
@@ -30,7 +30,7 @@ test(It i, typename std::iterator_traits<It>::difference_type n, It x)
     assert(rr.base() == x);
 }
 
-int main()
+int main(int, char**)
 {
     const char* s = "1234567890";
     test(random_access_iterator<const char*>(s+5), 5, random_access_iterator<const char*>(s+10));
@@ -48,4 +48,6 @@ int main()
         static_assert(it2 == it3, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op-=/difference_type.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op-=/difference_type.pass.cpp
index a484a67a7ddff9350109c408ede9cc4b2b51496d..ab92dc0686f5d636562dfc083e60f03e5547fcf8 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op-=/difference_type.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op-=/difference_type.pass.cpp
@@ -31,7 +31,7 @@ test(It i, typename std::iterator_traits<It>::difference_type n, It x)
     assert(&rr == &r);
 }
 
-int main()
+int main(int, char**)
 {
     const char* s = "1234567890";
     test(random_access_iterator<const char*>(s+5), 5, random_access_iterator<const char*>(s+10));
@@ -45,4 +45,6 @@ int main()
         static_assert(it1 == it2, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op.star/op_star.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op.star/op_star.pass.cpp
index efe3dbf9ccd72708d5fe4b406266c70c8299739f..820ee0060145478b8a5a304942ad7db659a92ab5 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op.star/op_star.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op.star/op_star.pass.cpp
@@ -43,7 +43,7 @@ test(It i, typename std::iterator_traits<It>::value_type x)
     assert(*r == x);
 }
 
-int main()
+int main(int, char**)
 {
     A a;
     test(&a+1, A());
@@ -58,4 +58,6 @@ int main()
         static_assert(*it2 == p[1], "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op=/reverse_iterator.fail.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op=/reverse_iterator.fail.cpp
index 0580eb098134d46179af53f08049f66f49621a05..071e3ef10503539ffca7cd4d7d792298f5eb92fc 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op=/reverse_iterator.fail.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op=/reverse_iterator.fail.cpp
@@ -31,8 +31,10 @@ test(U u)
 struct base {};
 struct derived {};
 
-int main()
+int main(int, char**)
 {
     derived d;
     test<base*>(&d);
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op=/reverse_iterator.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op=/reverse_iterator.pass.cpp
index e39476a98e9128d02d3d8f59b6702bdb93efe922..838bdc917e2a389c3b667ddc98dbc675186f8f4b 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op=/reverse_iterator.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op=/reverse_iterator.pass.cpp
@@ -37,7 +37,7 @@ test(U u)
 struct Base {};
 struct Derived : Base {};
 
-int main()
+int main(int, char**)
 {
     Derived d;
 
@@ -55,4 +55,6 @@ int main()
         static_assert(it2.base() == p, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op==/test.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op==/test.pass.cpp
index 066aa769b373b430f7ec36e2669288c1c903f384..7bd699bb9ead9bfb4040861323b7f181be488437 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op==/test.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.op==/test.pass.cpp
@@ -32,7 +32,7 @@ test(It l, It r, bool x)
     assert((r1 == r2) == x);
 }
 
-int main()
+int main(int, char**)
 {
     const char* s = "1234567890";
     test(bidirectional_iterator<const char*>(s), bidirectional_iterator<const char*>(s), true);
@@ -54,4 +54,6 @@ int main()
     }
 #endif
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.opdiff/test.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.opdiff/test.pass.cpp
index 2c7574eb454bcace04d9db63bb5263ddce9e99a3..ce90123480941969f43b655ae4f408a9bd8a09a3 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.opdiff/test.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.opdiff/test.pass.cpp
@@ -33,7 +33,7 @@ test(It1 l, It2 r, std::ptrdiff_t x)
     assert((r1 - r2) == x);
 }
 
-int main()
+int main(int, char**)
 {
     char s[3] = {0};
     test(random_access_iterator<const char*>(s), random_access_iterator<char*>(s), 0);
@@ -53,4 +53,6 @@ int main()
         static_assert( it2 - it1 == -1, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.opgt/test.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.opgt/test.pass.cpp
index d32932848cf64a1bb6be6cdf4e172e63c7c6b88e..86b19e3fc6a321a256b599860bd0256d08d90161 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.opgt/test.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.opgt/test.pass.cpp
@@ -32,7 +32,7 @@ test(It l, It r, bool x)
     assert((r1 > r2) == x);
 }
 
-int main()
+int main(int, char**)
 {
     const char* s = "1234567890";
     test(random_access_iterator<const char*>(s), random_access_iterator<const char*>(s), false);
@@ -53,4 +53,6 @@ int main()
         static_assert( (it1 > it3), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.opgt=/test.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.opgt=/test.pass.cpp
index b12f7c135d631431c5fb242eafb46da03d0ce6f0..de53281202f80bef39a248d18347b6f6683b9818 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.opgt=/test.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.opgt=/test.pass.cpp
@@ -32,7 +32,7 @@ test(It l, It r, bool x)
     assert((r1 >= r2) == x);
 }
 
-int main()
+int main(int, char**)
 {
     const char* s = "1234567890";
     test(random_access_iterator<const char*>(s), random_access_iterator<const char*>(s), true);
@@ -53,4 +53,6 @@ int main()
         static_assert( (it1 >= it3), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.opindex/difference_type.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.opindex/difference_type.pass.cpp
index a1b08f65c247bf2ff37ebd78d2f01d8fb473a7da..bc20d1381379f9f0ddb303f3360e72b6ca2f42a7 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.opindex/difference_type.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.opindex/difference_type.pass.cpp
@@ -30,7 +30,7 @@ test(It i, typename std::iterator_traits<It>::difference_type n,
     assert(rr == x);
 }
 
-int main()
+int main(int, char**)
 {
     const char* s = "1234567890";
     test(random_access_iterator<const char*>(s+5), 4, '1');
@@ -45,4 +45,6 @@ int main()
     static_assert(it1[4] == '1', "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.oplt/test.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.oplt/test.pass.cpp
index 7e4f27e7a7cd073e398eb7d56927d2307372d152..e49821f833caf0e48311756147ba63e4a554d615 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.oplt/test.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.oplt/test.pass.cpp
@@ -32,7 +32,7 @@ test(It l, It r, bool x)
     assert((r1 < r2) == x);
 }
 
-int main()
+int main(int, char**)
 {
     const char* s = "1234567890";
     test(random_access_iterator<const char*>(s), random_access_iterator<const char*>(s), false);
@@ -53,4 +53,6 @@ int main()
         static_assert(!(it1 < it3), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.oplt=/test.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.oplt=/test.pass.cpp
index 8934d68efc595d148d426f7ba6ebbdb65eca4976..92752361152f64628e451a4ed31d06289228ff46 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.oplt=/test.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.oplt=/test.pass.cpp
@@ -32,7 +32,7 @@ test(It l, It r, bool x)
     assert((r1 <= r2) == x);
 }
 
-int main()
+int main(int, char**)
 {
     const char* s = "1234567890";
     test(random_access_iterator<const char*>(s), random_access_iterator<const char*>(s), true);
@@ -53,4 +53,6 @@ int main()
         static_assert(!(it1 <= it3), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.opref/op_arrow.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.opref/op_arrow.pass.cpp
index ce0b470a61279b006a7aa3623dad75bb827876e7..f16fb2757a533c0180378b3f927aa6812bc66769 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.opref/op_arrow.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.opref/op_arrow.pass.cpp
@@ -76,7 +76,7 @@ public:
 
 TEST_CONSTEXPR  C gC;
 
-int main()
+int main(int, char**)
 {
     A a;
     test(&a+1, A());
@@ -115,4 +115,6 @@ int main()
     {
         ((void)gC);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.opsum/difference_type.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.opsum/difference_type.pass.cpp
index 25876d0726746a263e70181921c6cd6542df1a14..ba38448515d78ac094a1f8b2cd37cfc6f776bc02 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.opsum/difference_type.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.ops/reverse.iter.opsum/difference_type.pass.cpp
@@ -31,7 +31,7 @@ test(It i, typename std::iterator_traits<It>::difference_type n, It x)
     assert(rr.base() == x);
 }
 
-int main()
+int main(int, char**)
 {
     const char* s = "1234567890";
     test(random_access_iterator<const char*>(s+5), 5, random_access_iterator<const char*>(s));
@@ -49,4 +49,6 @@ int main()
         static_assert(it2 != it3, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.requirements/nothing_to_do.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.requirements/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.requirements/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iter.requirements/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iterator/types.pass.cpp b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iterator/types.pass.cpp
index 7242f6a347c3ffa520b37bc54de519349bea758a..11ac625258c71c6bc97cc9ca4674c706a39a0923 100644
--- a/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iterator/types.pass.cpp
+++ b/libcxx/test/std/iterators/predef.iterators/reverse.iterators/reverse.iterator/types.pass.cpp
@@ -52,9 +52,11 @@ test()
     static_assert((std::is_same<typename R::iterator_category, typename T::iterator_category>::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     test<bidirectional_iterator<char*> >();
     test<random_access_iterator<char*> >();
     test<char*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.cons/copy.pass.cpp b/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.cons/copy.pass.cpp
index 4ee68b5fc7ae9b5f6c415d8c27e86b708a24f20d..d6a3b0862879af26e7d06b938e5ed2cad085f0f1 100644
--- a/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.cons/copy.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.cons/copy.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::istream_iterator<int> io;
@@ -36,4 +36,6 @@ int main()
         j = *i;
         assert(j == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.cons/default.fail.cpp b/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.cons/default.fail.cpp
index 1ffe4dcfe3cb73250fda8351a472f35e1a4354a4..e2bebbaea10c89bebe504bab2cce8afb8027d91d 100644
--- a/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.cons/default.fail.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.cons/default.fail.cpp
@@ -19,7 +19,7 @@
 
 struct S { S(); }; // not constexpr
 
-int main()
+int main(int, char**)
 {
 #if TEST_STD_VER >= 11
     {
@@ -28,4 +28,6 @@ int main()
 #else
 #error "C++11 only test"
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.cons/default.pass.cpp b/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.cons/default.pass.cpp
index f569d3206d8f56c523d2a3c8bd0492dcc9d827b9..fa43566ddde9377422d03f07d54b1308cc3c08d8 100644
--- a/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.cons/default.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.cons/default.pass.cpp
@@ -42,7 +42,7 @@ void operator ()() const {}
 #endif
 
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::istream_iterator<int> T;
@@ -61,4 +61,6 @@ int main()
     test_trivial<S>()();
     test_trivial<std::string>()();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.cons/istream.pass.cpp b/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.cons/istream.pass.cpp
index 50b40aba48cba96ae70bf78d5a7c51c0ae42e96e..a4c47974daee7c2321417bd2df58fdc447f099c3 100644
--- a/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.cons/istream.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.cons/istream.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::istringstream inf(" 1 23");
     std::istream_iterator<int> i(inf);
@@ -26,4 +26,6 @@ int main()
     int j = 0;
     inf >> j;
     assert(j == 23);
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.ops/arrow.pass.cpp b/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.ops/arrow.pass.cpp
index a2862b4031f3ef3d7e4d9fd7dacc369b7842d726..5409cc5955b4cd94872f8314a072a5a88b5dd93b 100644
--- a/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.ops/arrow.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.ops/arrow.pass.cpp
@@ -29,10 +29,12 @@ std::istream& operator>>(std::istream& is, A& a)
     return is >> a.d_ >> a.i_;
 }
 
-int main()
+int main(int, char**)
 {
     std::istringstream inf("1.5  23 ");
     std::istream_iterator<A> i(inf);
     assert(i->d_ == 1.5);
     assert(i->i_ == 23);
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.ops/dereference.pass.cpp b/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.ops/dereference.pass.cpp
index 38ffe4bfd7dfe768729caa294ff7cd19356bd2bf..c99e723b04104f40d39bec0aa1ebf179561434cc 100644
--- a/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.ops/dereference.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.ops/dereference.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::istringstream inf(" 1 23");
     std::istream_iterator<int> i(inf);
@@ -30,4 +30,6 @@ int main()
     assert(j == 23);
     j = *i;
     assert(j == 23);
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.ops/equal.pass.cpp b/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.ops/equal.pass.cpp
index 5ba335c5edf1eb1092ba7424f5064b682d3ca2ce..616a3ca38520cc1ce49a0b71abfd920e021368d7 100644
--- a/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.ops/equal.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.ops/equal.pass.cpp
@@ -22,7 +22,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::istringstream inf1(" 1 23");
     std::istringstream inf2(" 1 23");
@@ -51,4 +51,6 @@ int main()
 
     assert(std::operator==(i1, i2));
     assert(std::operator!=(i1, i3));
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.ops/post_increment.pass.cpp b/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.ops/post_increment.pass.cpp
index b32f358cf243bc80c61858bc90050b3b3c7e7f0b..83d206e719b3b13725e8743c4c200062d5af269a 100644
--- a/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.ops/post_increment.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.ops/post_increment.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::istringstream inf(" 1 23");
     std::istream_iterator<int> i(inf);
@@ -28,4 +28,6 @@ int main()
     j = 0;
     j = *icopy;
     assert(j == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.ops/pre_increment.pass.cpp b/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.ops/pre_increment.pass.cpp
index 6a361ff7172b360fa80e443f26ea275d46c05340..ab61f57f9dc88ce8cc804016867a09affb7f4f4e 100644
--- a/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.ops/pre_increment.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/istream.iterator/istream.iterator.ops/pre_increment.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::istringstream inf(" 1 23");
     std::istream_iterator<int> i(inf);
@@ -25,4 +25,6 @@ int main()
     int j = 0;
     j = *i;
     assert(j == 23);
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/istream.iterator/types.pass.cpp b/libcxx/test/std/iterators/stream.iterators/istream.iterator/types.pass.cpp
index 9a7185c1b8904d50843b2f340c99b45dca83e5a2..5170b1e536581c68cb3697416eef6366879f2458 100644
--- a/libcxx/test/std/iterators/stream.iterators/istream.iterator/types.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/istream.iterator/types.pass.cpp
@@ -41,7 +41,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::istream_iterator<double> I1; // double is trivially destructible
 #if TEST_STD_VER <= 14
@@ -82,4 +82,6 @@ int main()
     typedef std::istream_iterator<std::string> I3; // string is NOT trivially destructible
     static_assert(!std::is_trivially_copy_constructible<I3>::value, "");
     static_assert(!std::is_trivially_destructible<I3>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator.cons/default.pass.cpp b/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator.cons/default.pass.cpp
index d7e1a31e571109a4c8bacc0bf020e84274d6413e..9502e0da7b98e9524b5b453393689cbc5a2c0cd1 100644
--- a/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator.cons/default.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator.cons/default.pass.cpp
@@ -21,7 +21,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::istreambuf_iterator<char> T;
@@ -41,4 +41,6 @@ int main()
         (void)it2;
 #endif
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator.cons/istream.pass.cpp b/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator.cons/istream.pass.cpp
index a7927cbb2f0a65cfde3cc347fc72b224cb9be5aa..b51d19a8e5e94e5fb890bf00461493b61b976202 100644
--- a/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator.cons/istream.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator.cons/istream.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::istringstream inf;
@@ -38,4 +38,6 @@ int main()
         std::istreambuf_iterator<wchar_t> i(inf);
         assert(i != std::istreambuf_iterator<wchar_t>());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator.cons/proxy.pass.cpp b/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator.cons/proxy.pass.cpp
index 6b4719cadb0bbcd567eeef47cf6ae37695ecc676..87afe840d03e0396429aea6a9424aa432b840a00 100644
--- a/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator.cons/proxy.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator.cons/proxy.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::istringstream inf("abc");
@@ -32,4 +32,6 @@ int main()
         assert(i != std::istreambuf_iterator<wchar_t>());
         assert(*i == L'b');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator.cons/streambuf.pass.cpp b/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator.cons/streambuf.pass.cpp
index 2b94d8c97563320d037ab3c49cf68f8ac65abb1d..d92cddde1f155e6cfa47dcfbd8a677d7975d1a73 100644
--- a/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator.cons/streambuf.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator.cons/streambuf.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::istreambuf_iterator<char> i(nullptr);
@@ -46,4 +46,6 @@ int main()
         std::istreambuf_iterator<wchar_t> i(inf.rdbuf());
         assert(i != std::istreambuf_iterator<wchar_t>());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator_equal/equal.pass.cpp b/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator_equal/equal.pass.cpp
index 9b0034131619d1344a332392784fa0e8e7deb685..1fcdf7af146d443ba852b4249054f2386485ec9f 100644
--- a/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator_equal/equal.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator_equal/equal.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::istringstream inf1("abc");
@@ -96,4 +96,6 @@ int main()
         assert( i5.equal(i4));
         assert( i5.equal(i5));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator_op!=/not_equal.pass.cpp b/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator_op!=/not_equal.pass.cpp
index 7e50c68f7c1818ac3b803b9f3b07960ba40475c1..d4184aa6ce66ceb828716446db92d1a4a1a90900 100644
--- a/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator_op!=/not_equal.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator_op!=/not_equal.pass.cpp
@@ -18,7 +18,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::istringstream inf1("abc");
@@ -98,4 +98,6 @@ int main()
         assert(!(i5 != i4));
         assert(!(i5 != i5));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator_op++/dereference.pass.cpp b/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator_op++/dereference.pass.cpp
index 28cb7a93a4aa53d38c12a64eb2e3609a0d30d218..d60302ad40d74ded22f22bf4aef15e99744123bf 100644
--- a/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator_op++/dereference.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator_op++/dereference.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::istringstream inf("abc");
@@ -36,4 +36,6 @@ int main()
         ++i;
         assert(*i == L'c');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator_op==/equal.pass.cpp b/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator_op==/equal.pass.cpp
index ede97380bb8b458d1272261014233979607232bb..875989f5df56892695535bf8e88b3d17c3ca8bd2 100644
--- a/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator_op==/equal.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator_op==/equal.pass.cpp
@@ -18,7 +18,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::istringstream inf1("abc");
@@ -98,4 +98,6 @@ int main()
         assert( (i5 == i4));
         assert( (i5 == i5));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator_op_astrk/post_increment.pass.cpp b/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator_op_astrk/post_increment.pass.cpp
index 15c266d731455b86f37ff64716042a29995b209f..e3121494df420595c0155819247900eb59830761 100644
--- a/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator_op_astrk/post_increment.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator_op_astrk/post_increment.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::istringstream inf("abc");
@@ -34,4 +34,6 @@ int main()
         assert(*i++ == L'c');
         assert(i == std::istreambuf_iterator<wchar_t>());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator_op_astrk/pre_increment.pass.cpp b/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator_op_astrk/pre_increment.pass.cpp
index 148bd725a7f99309f186923f14c6c8ca257b8823..9d05cbda340d7679574e9dd5dafe8484198de014 100644
--- a/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator_op_astrk/pre_increment.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator_op_astrk/pre_increment.pass.cpp
@@ -17,7 +17,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::istringstream inf("abc");
@@ -35,4 +35,6 @@ int main()
         assert(*++i == L'c');
         assert(++i == std::istreambuf_iterator<wchar_t>());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator_proxy/proxy.pass.cpp b/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator_proxy/proxy.pass.cpp
index 2535d99139798a6ad5f76ef6e302e2c3547b127c..74e1813d512b0a5d7d801a311ba3b0a1944f032f 100644
--- a/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator_proxy/proxy.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/istreambuf.iterator_proxy/proxy.pass.cpp
@@ -28,7 +28,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::istringstream inf("abc");
@@ -40,4 +40,6 @@ int main()
         std::istreambuf_iterator<wchar_t> i(inf);
         assert(*i++ == L'a');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/types.pass.cpp b/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/types.pass.cpp
index 829d1f0a6dfdd8b0de8d3c3ad1135a8c78b8f6c4..a6c6435f10a49423b0de7c236859c70fc11801a0 100644
--- a/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/types.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/istreambuf.iterator/types.pass.cpp
@@ -34,7 +34,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::istreambuf_iterator<char> I1;
     static_assert((std::is_same<I1::iterator_category, std::input_iterator_tag>::value), "");
@@ -65,4 +65,6 @@ int main()
     static_assert((std::is_nothrow_default_constructible<I2>::value), "" );
     static_assert((std::is_trivially_copy_constructible<I2>::value), "" );
     static_assert((std::is_trivially_destructible<I2>::value), "" );
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/iterator.range/begin_array.pass.cpp b/libcxx/test/std/iterators/stream.iterators/iterator.range/begin_array.pass.cpp
index 3521b05fa8f0cca7a0baa50d931580bfe2437d2e..8d7500cf292d6179847a8b15e325fc8c790e44b2 100644
--- a/libcxx/test/std/iterators/stream.iterators/iterator.range/begin_array.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/iterator.range/begin_array.pass.cpp
@@ -13,11 +13,13 @@
 #include <iterator>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int ia[] = {1, 2, 3};
     int* i = std::begin(ia);
     assert(*i == 1);
     *i = 2;
     assert(ia[0] == 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/iterator.range/begin_const.pass.cpp b/libcxx/test/std/iterators/stream.iterators/iterator.range/begin_const.pass.cpp
index 255a837e734b6756099a8403c9bca25c3a325cad..06b5e7907e8060cfb96733447336660327edd8fd 100644
--- a/libcxx/test/std/iterators/stream.iterators/iterator.range/begin_const.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/iterator.range/begin_const.pass.cpp
@@ -13,10 +13,12 @@
 #include <vector>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int ia[] = {1, 2, 3};
     const std::vector<int> v(ia, ia + sizeof(ia)/sizeof(ia[0]));
     std::vector<int>::const_iterator i = begin(v);
     assert(*i == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/iterator.range/begin_non_const.pass.cpp b/libcxx/test/std/iterators/stream.iterators/iterator.range/begin_non_const.pass.cpp
index bc99f7a408c6320e6df85e2395f211ccb992d734..75e61d3b41178bbed0e44f726962f41156f087ae 100644
--- a/libcxx/test/std/iterators/stream.iterators/iterator.range/begin_non_const.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/iterator.range/begin_non_const.pass.cpp
@@ -13,7 +13,7 @@
 #include <vector>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int ia[] = {1, 2, 3};
     std::vector<int> v(ia, ia + sizeof(ia)/sizeof(ia[0]));
@@ -21,4 +21,6 @@ int main()
     assert(*i == 1);
     *i = 2;
     assert(*i == 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/iterator.range/end_array.pass.cpp b/libcxx/test/std/iterators/stream.iterators/iterator.range/end_array.pass.cpp
index 0f21309baab7175988a74f05b6936765ac37e3f0..a6721155afd16d9d50414906ccbab6c8b9a2554a 100644
--- a/libcxx/test/std/iterators/stream.iterators/iterator.range/end_array.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/iterator.range/end_array.pass.cpp
@@ -13,11 +13,13 @@
 #include <iterator>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int ia[] = {1, 2, 3};
     int* i = std::begin(ia);
     int* e = std::end(ia);
     assert(e == ia + 3);
     assert(e - i == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/iterator.range/end_const.pass.cpp b/libcxx/test/std/iterators/stream.iterators/iterator.range/end_const.pass.cpp
index 45796233202ef3b9fd5a66bd5c37867d922cd6ea..78a6affd8a29c181d42a63d201bfb5a669c21dda 100644
--- a/libcxx/test/std/iterators/stream.iterators/iterator.range/end_const.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/iterator.range/end_const.pass.cpp
@@ -13,10 +13,12 @@
 #include <vector>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int ia[] = {1, 2, 3};
     const std::vector<int> v(ia, ia + sizeof(ia)/sizeof(ia[0]));
     std::vector<int>::const_iterator i = end(v);
     assert(i == v.cend());
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/iterator.range/end_non_const.pass.cpp b/libcxx/test/std/iterators/stream.iterators/iterator.range/end_non_const.pass.cpp
index 8fa2a4e5600e1ffda5f71267812d2f09868c42aa..9970ec922c384f2bc982248a4160374fe7d2ad3e 100644
--- a/libcxx/test/std/iterators/stream.iterators/iterator.range/end_non_const.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/iterator.range/end_non_const.pass.cpp
@@ -13,10 +13,12 @@
 #include <vector>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int ia[] = {1, 2, 3};
     std::vector<int> v(ia, ia + sizeof(ia)/sizeof(ia[0]));
     std::vector<int>::iterator i = end(v);
     assert(i == v.end());
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/nothing_to_do.pass.cpp b/libcxx/test/std/iterators/stream.iterators/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/iterators/stream.iterators/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/ostream.iterator/ostream.iterator.cons.des/copy.pass.cpp b/libcxx/test/std/iterators/stream.iterators/ostream.iterator/ostream.iterator.cons.des/copy.pass.cpp
index 24cf15ff1beb3a2f474ec86580a81221e7d79a81..491f3bc1cec4617164f16c78b7af7da861260bd3 100644
--- a/libcxx/test/std/iterators/stream.iterators/ostream.iterator/ostream.iterator.cons.des/copy.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/ostream.iterator/ostream.iterator.cons.des/copy.pass.cpp
@@ -16,11 +16,13 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::ostringstream outf;
     std::ostream_iterator<int> i(outf);
     std::ostream_iterator<int> j = i;
     assert(outf.good());
     ((void)j);
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/ostream.iterator/ostream.iterator.cons.des/ostream.pass.cpp b/libcxx/test/std/iterators/stream.iterators/ostream.iterator/ostream.iterator.cons.des/ostream.pass.cpp
index 1de0ea2eabe2bdddb80405d275da6b02d10ce72d..78abcfab677e25f1295d58e5925d9aedaf26471f 100644
--- a/libcxx/test/std/iterators/stream.iterators/ostream.iterator/ostream.iterator.cons.des/ostream.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/ostream.iterator/ostream.iterator.cons.des/ostream.pass.cpp
@@ -23,7 +23,7 @@ typedef std::basic_ostream<char, MyTraits> BasicStream;
 
 void operator&(BasicStream const&) {}
 
-int main()
+int main(int, char**)
 {
     {
         std::ostringstream outf;
@@ -35,4 +35,6 @@ int main()
         std::ostream_iterator<int, char, MyTraits> i(outf);
         assert(outf.good());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/ostream.iterator/ostream.iterator.cons.des/ostream_delim.pass.cpp b/libcxx/test/std/iterators/stream.iterators/ostream.iterator/ostream.iterator.cons.des/ostream_delim.pass.cpp
index 7b4422f94bde763a0a02e14276f0492530e7252b..2c48189f91a886f9ece8706967c10af90943e7d0 100644
--- a/libcxx/test/std/iterators/stream.iterators/ostream.iterator/ostream.iterator.cons.des/ostream_delim.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/ostream.iterator/ostream.iterator.cons.des/ostream_delim.pass.cpp
@@ -24,7 +24,7 @@ typedef std::basic_ostream<char, MyTraits> BasicStream;
 
 void operator&(BasicStream const&) {}
 
-int main()
+int main(int, char**)
 {
     {
         std::ostringstream outf;
@@ -41,4 +41,6 @@ int main()
         std::ostream_iterator<int, char, MyTraits> i(outf, ", ");
         assert(outf.good());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/ostream.iterator/ostream.iterator.ops/assign_t.pass.cpp b/libcxx/test/std/iterators/stream.iterators/ostream.iterator/ostream.iterator.ops/assign_t.pass.cpp
index dea585c3c04729ae69f0b6bc56ecb0459d27abd4..5a2f2cc99f2586f6383097e10ca3832511c6361a 100644
--- a/libcxx/test/std/iterators/stream.iterators/ostream.iterator/ostream.iterator.ops/assign_t.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/ostream.iterator/ostream.iterator.ops/assign_t.pass.cpp
@@ -26,7 +26,7 @@
 #pragma warning(disable: 4244) // conversion from 'X' to 'Y', possible loss of data
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         std::ostringstream outf;
@@ -52,4 +52,6 @@ int main()
         i = 2.4;
         assert(outf.str() == L"2, ");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/ostream.iterator/ostream.iterator.ops/dereference.pass.cpp b/libcxx/test/std/iterators/stream.iterators/ostream.iterator/ostream.iterator.ops/dereference.pass.cpp
index 4d79f7c1d568a794727fe7465f9ed97a99b91bcc..6cb190ab4913caaefb8159ba505d890f324b9346 100644
--- a/libcxx/test/std/iterators/stream.iterators/ostream.iterator/ostream.iterator.ops/dereference.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/ostream.iterator/ostream.iterator.ops/dereference.pass.cpp
@@ -16,10 +16,12 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::ostringstream os;
     std::ostream_iterator<int> i(os);
     std::ostream_iterator<int>& iref = *i;
     assert(&iref == &i);
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/ostream.iterator/ostream.iterator.ops/increment.pass.cpp b/libcxx/test/std/iterators/stream.iterators/ostream.iterator/ostream.iterator.ops/increment.pass.cpp
index d93aad6cce52b23e068325f906bdd5f472f9eecd..eedab8115d87ce1654a69561b947e70da0d50dad 100644
--- a/libcxx/test/std/iterators/stream.iterators/ostream.iterator/ostream.iterator.ops/increment.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/ostream.iterator/ostream.iterator.ops/increment.pass.cpp
@@ -17,7 +17,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::ostringstream os;
     std::ostream_iterator<int> i(os);
@@ -25,4 +25,6 @@ int main()
     assert(&iref1 == &i);
     std::ostream_iterator<int>& iref2 = i++;
     assert(&iref2 == &i);
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/ostream.iterator/types.pass.cpp b/libcxx/test/std/iterators/stream.iterators/ostream.iterator/types.pass.cpp
index 716ba2bfdc38d00c32c9c44ff0f8cf506d2608da..950c7dfe8c0b5e275bc6e74ac9fccf49dab40068 100644
--- a/libcxx/test/std/iterators/stream.iterators/ostream.iterator/types.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/ostream.iterator/types.pass.cpp
@@ -24,7 +24,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::ostream_iterator<double> I1;
 #if TEST_STD_VER <= 14
@@ -54,4 +54,6 @@ int main()
     static_assert((std::is_same<I2::char_type, wchar_t>::value), "");
     static_assert((std::is_same<I2::traits_type, std::char_traits<wchar_t> >::value), "");
     static_assert((std::is_same<I2::ostream_type, std::wostream>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/ostreambuf.iter.cons/ostream.pass.cpp b/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/ostreambuf.iter.cons/ostream.pass.cpp
index 0c28a77ac168bc890d54e60658f480e173aa16b0..aa6031a8ad8a55980df995899b270cab23cf2dd2 100644
--- a/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/ostreambuf.iter.cons/ostream.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/ostreambuf.iter.cons/ostream.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::ostringstream outf;
@@ -28,4 +28,6 @@ int main()
         std::ostreambuf_iterator<wchar_t> i(outf);
         assert(!i.failed());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/ostreambuf.iter.cons/streambuf.pass.cpp b/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/ostreambuf.iter.cons/streambuf.pass.cpp
index 0d2c85bef849f8003ab8b46240f087d4d7bb7192..2c64dc29fdb2666527fbc94e83908c3a36cef76e 100644
--- a/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/ostreambuf.iter.cons/streambuf.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/ostreambuf.iter.cons/streambuf.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::ostringstream outf;
@@ -28,4 +28,6 @@ int main()
         std::ostreambuf_iterator<wchar_t> i(outf.rdbuf());
         assert(!i.failed());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/ostreambuf.iter.ops/assign_c.pass.cpp b/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/ostreambuf.iter.ops/assign_c.pass.cpp
index 45e57fc80076fcdfef200fda5b630592b516e1ef..fe51fba1fd5f89f5345ac29f1a0fc8575d2eba4a 100644
--- a/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/ostreambuf.iter.ops/assign_c.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/ostreambuf.iter.ops/assign_c.pass.cpp
@@ -17,7 +17,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::ostringstream outf;
@@ -35,4 +35,6 @@ int main()
         i = L'b';
         assert(outf.str() == L"ab");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/ostreambuf.iter.ops/deref.pass.cpp b/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/ostreambuf.iter.ops/deref.pass.cpp
index e33a5a5c8f48dfd7ac99e0fb66af78484d405487..4904320b0a00463bc580671c986fd1f91a947731 100644
--- a/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/ostreambuf.iter.ops/deref.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/ostreambuf.iter.ops/deref.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::ostringstream outf;
@@ -30,4 +30,6 @@ int main()
         std::ostreambuf_iterator<wchar_t>& iref = *i;
         assert(&iref == &i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/ostreambuf.iter.ops/failed.pass.cpp b/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/ostreambuf.iter.ops/failed.pass.cpp
index b52fce81344d4231953fc106bbca12b8214b176f..fa67513ad6e28123dc3c08fc450c2cac7469de62 100644
--- a/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/ostreambuf.iter.ops/failed.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/ostreambuf.iter.ops/failed.pass.cpp
@@ -25,7 +25,7 @@ struct my_streambuf : public std::basic_streambuf<Char,Traits> {
     int_type sputc(char_type) { return Traits::eof(); }
     };
 
-int main()
+int main(int, char**)
 {
     {
         my_streambuf<char> buf;
@@ -39,4 +39,6 @@ int main()
         i = L'a';
         assert(i.failed());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/ostreambuf.iter.ops/increment.pass.cpp b/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/ostreambuf.iter.ops/increment.pass.cpp
index c765a5c2daad00d07c73fd66f73d312893f50bd4..81ae55ae7a67700f6824dca1212799f40e872b3a 100644
--- a/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/ostreambuf.iter.ops/increment.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/ostreambuf.iter.ops/increment.pass.cpp
@@ -17,7 +17,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::ostringstream outf;
@@ -35,4 +35,6 @@ int main()
         std::ostreambuf_iterator<wchar_t>& iref2 = i++;
         assert(&iref2 == &i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/types.pass.cpp b/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/types.pass.cpp
index 346d8b8496f7fc264ead26858bc8ec50915c1b0d..671a09bb7a3fae8fe15defb1a8ef5c2e36e5bd77 100644
--- a/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/types.pass.cpp
+++ b/libcxx/test/std/iterators/stream.iterators/ostreambuf.iterator/types.pass.cpp
@@ -25,7 +25,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::ostreambuf_iterator<char> I1;
 #if TEST_STD_VER <= 14
@@ -58,4 +58,6 @@ int main()
     static_assert((std::is_same<I2::traits_type, std::char_traits<wchar_t> >::value), "");
     static_assert((std::is_same<I2::streambuf_type, std::wstreambuf>::value), "");
     static_assert((std::is_same<I2::ostream_type, std::wostream>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/cmp/cmp.common/common_comparison_category.pass.cpp b/libcxx/test/std/language.support/cmp/cmp.common/common_comparison_category.pass.cpp
index 4c999637ffbfccc6a1b0473bbab78a56aff2813e..218291b6b49fc035999c473fe98df82355a693c7 100644
--- a/libcxx/test/std/language.support/cmp/cmp.common/common_comparison_category.pass.cpp
+++ b/libcxx/test/std/language.support/cmp/cmp.common/common_comparison_category.pass.cpp
@@ -33,7 +33,7 @@ void test_cat() {
 
 // [class.spaceship]p4: The 'common comparison type' U of a possibly-empty list
 //   of 'n' types T0, T1, ..., TN, is defined as follows:
-int main() {
+int main(int, char**) {
   using WE = std::weak_equality;
   using SE = std::strong_equality;
   using PO = std::partial_ordering;
@@ -89,4 +89,6 @@ int main() {
     test_cat<SO, SO>();
     test_cat<SO, SO, SO>();
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/cmp/cmp.partialord/partialord.pass.cpp b/libcxx/test/std/language.support/cmp/cmp.partialord/partialord.pass.cpp
index 6c51b7a208d20837932c55100b7f5b7df83aa744..f2e673db696f94f668154da8e4738c8007e1274d 100644
--- a/libcxx/test/std/language.support/cmp/cmp.partialord/partialord.pass.cpp
+++ b/libcxx/test/std/language.support/cmp/cmp.partialord/partialord.pass.cpp
@@ -155,9 +155,11 @@ constexpr bool test_constexpr() {
   return true;
 }
 
-int main() {
+int main(int, char**) {
   test_static_members();
   test_signatures();
   static_assert(test_conversion(), "conversion test failed");
   static_assert(test_constexpr(), "constexpr test failed");
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/cmp/cmp.strongeq/cmp.strongeq.pass.cpp b/libcxx/test/std/language.support/cmp/cmp.strongeq/cmp.strongeq.pass.cpp
index e34cadc55ce088c5cac503846cd37d8481fb402f..a5af910a5e05b3023501854f48bda6b974fb84a1 100644
--- a/libcxx/test/std/language.support/cmp/cmp.strongeq/cmp.strongeq.pass.cpp
+++ b/libcxx/test/std/language.support/cmp/cmp.strongeq/cmp.strongeq.pass.cpp
@@ -87,9 +87,11 @@ constexpr bool test_constexpr() {
   return true;
 }
 
-int main() {
+int main(int, char**) {
   test_static_members();
   test_signatures();
   test_conversion();
   static_assert(test_constexpr(), "constexpr test failed");
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/cmp/cmp.strongord/strongord.pass.cpp b/libcxx/test/std/language.support/cmp/cmp.strongord/strongord.pass.cpp
index 4b75e5d51ef22dfdb0255dec463cf4619665c35d..a31fd34d4f130b33310d83b76b7767c1a89cedd8 100644
--- a/libcxx/test/std/language.support/cmp/cmp.strongord/strongord.pass.cpp
+++ b/libcxx/test/std/language.support/cmp/cmp.strongord/strongord.pass.cpp
@@ -203,9 +203,11 @@ constexpr bool test_constexpr() {
   return true;
 }
 
-int main() {
+int main(int, char**) {
   test_static_members();
   test_signatures();
   static_assert(test_conversion(), "conversion test failed");
   static_assert(test_constexpr(), "constexpr test failed");
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/cmp/cmp.weakeq/cmp.weakeq.pass.cpp b/libcxx/test/std/language.support/cmp/cmp.weakeq/cmp.weakeq.pass.cpp
index dae2f214717228cea2f81dfc3ca8615f63e5ae1c..367aac6bebe718706c1577e3ec2f2d980962502c 100644
--- a/libcxx/test/std/language.support/cmp/cmp.weakeq/cmp.weakeq.pass.cpp
+++ b/libcxx/test/std/language.support/cmp/cmp.weakeq/cmp.weakeq.pass.cpp
@@ -62,8 +62,10 @@ constexpr bool test_constexpr() {
   return true;
 }
 
-int main() {
+int main(int, char**) {
   test_static_members();
   test_signatures();
   static_assert(test_constexpr(), "constexpr test failed");
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/cmp/cmp.weakord/weakord.pass.cpp b/libcxx/test/std/language.support/cmp/cmp.weakord/weakord.pass.cpp
index 6e9e7d4410601c1cf02ce476979c8a9d94869674..ada8d240b6d27559cd34f9f1009bc2f081ab5207 100644
--- a/libcxx/test/std/language.support/cmp/cmp.weakord/weakord.pass.cpp
+++ b/libcxx/test/std/language.support/cmp/cmp.weakord/weakord.pass.cpp
@@ -160,9 +160,11 @@ constexpr bool test_constexpr() {
   return true;
 }
 
-int main() {
+int main(int, char**) {
   test_static_members();
   test_signatures();
   static_assert(test_conversion(), "conversion test failed");
   static_assert(test_constexpr(), "constexpr test failed");
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/cstdint/cstdint.syn/cstdint.pass.cpp b/libcxx/test/std/language.support/cstdint/cstdint.syn/cstdint.pass.cpp
index 6f46342da94c0924e9a8907ade53159c0b71b4bf..ec4afd7f69dba9156662c0d3281ae91769dde19e 100644
--- a/libcxx/test/std/language.support/cstdint/cstdint.syn/cstdint.pass.cpp
+++ b/libcxx/test/std/language.support/cstdint/cstdint.syn/cstdint.pass.cpp
@@ -18,7 +18,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     // typedef std::int8_t
     static_assert(sizeof(std::int8_t)*CHAR_BIT == 8,
@@ -288,4 +288,6 @@ int main()
 #ifndef UINTMAX_C
 #error UINTMAX_C not defined
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/nothing_to_do.pass.cpp b/libcxx/test/std/language.support/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/language.support/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/language.support/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/align_val_t.pass.cpp b/libcxx/test/std/language.support/support.dynamic/align_val_t.pass.cpp
index 1b0b4c00baaaad4dd84f99ffbfb3202523ed88e5..6e65518233a896758fbd244c6f837ed2f67190be 100644
--- a/libcxx/test/std/language.support/support.dynamic/align_val_t.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/align_val_t.pass.cpp
@@ -14,7 +14,7 @@
 
 #include "test_macros.h"
 
-int main() {
+int main(int, char**) {
   {
     static_assert(std::is_enum<std::align_val_t>::value, "");
     static_assert(std::is_same<std::underlying_type<std::align_val_t>::type, std::size_t>::value, "");
@@ -30,4 +30,6 @@ int main() {
     static_assert(b == std::align_val_t(32), "");
     static_assert(static_cast<std::size_t>(c) == (std::size_t)-1, "");
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/alloc.errors/bad.alloc/bad_alloc.pass.cpp b/libcxx/test/std/language.support/support.dynamic/alloc.errors/bad.alloc/bad_alloc.pass.cpp
index 713e66245c05ba0ef3676e972aa8d59fdec0df2c..f0b2bd21fec695b82b21d079acb30de8b8f5d332 100644
--- a/libcxx/test/std/language.support/support.dynamic/alloc.errors/bad.alloc/bad_alloc.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/alloc.errors/bad.alloc/bad_alloc.pass.cpp
@@ -12,7 +12,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::exception, std::bad_alloc>::value),
                  "std::is_base_of<std::exception, std::bad_alloc>::value");
@@ -23,4 +23,6 @@ int main()
     b2 = b;
     const char* w = b2.what();
     assert(w);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/alloc.errors/new.badlength/bad_array_new_length.pass.cpp b/libcxx/test/std/language.support/support.dynamic/alloc.errors/new.badlength/bad_array_new_length.pass.cpp
index d2fefdd1b94196a30ea0a11d16a7856e9585df05..35fd130412525eb5df47bcbee8266e8d38039961 100644
--- a/libcxx/test/std/language.support/support.dynamic/alloc.errors/new.badlength/bad_array_new_length.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/alloc.errors/new.badlength/bad_array_new_length.pass.cpp
@@ -12,7 +12,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::bad_alloc, std::bad_array_new_length>::value),
                   "std::is_base_of<std::bad_alloc, std::bad_array_new_length>::value");
@@ -23,4 +23,6 @@ int main()
     b2 = b;
     const char* w = b2.what();
     assert(w);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/alloc.errors/new.handler/new_handler.pass.cpp b/libcxx/test/std/language.support/support.dynamic/alloc.errors/new.handler/new_handler.pass.cpp
index f5681d8d92fcfd5d68eb2b88be6966683ba53142..b69fe15232c0c2daf28729316543f2c55e96435f 100644
--- a/libcxx/test/std/language.support/support.dynamic/alloc.errors/new.handler/new_handler.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/alloc.errors/new.handler/new_handler.pass.cpp
@@ -14,9 +14,11 @@
 
 void f() {}
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::new_handler, void(*)()>::value), "");
     std::new_handler p = f;
     assert(p == &f);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/alloc.errors/nothing_to_do.pass.cpp b/libcxx/test/std/language.support/support.dynamic/alloc.errors/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/language.support/support.dynamic/alloc.errors/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/alloc.errors/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/alloc.errors/set.new.handler/get_new_handler.pass.cpp b/libcxx/test/std/language.support/support.dynamic/alloc.errors/set.new.handler/get_new_handler.pass.cpp
index 922ab9db49c41d76a7562da1078c754211287a40..a9ed3b0cf3687f1ef446d20570d106bf4195fecd 100644
--- a/libcxx/test/std/language.support/support.dynamic/alloc.errors/set.new.handler/get_new_handler.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/alloc.errors/set.new.handler/get_new_handler.pass.cpp
@@ -14,11 +14,13 @@
 void f1() {}
 void f2() {}
 
-int main()
+int main(int, char**)
 {
     assert(std::get_new_handler() == 0);
     std::set_new_handler(f1);
     assert(std::get_new_handler() == f1);
     std::set_new_handler(f2);
     assert(std::get_new_handler() == f2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/alloc.errors/set.new.handler/set_new_handler.pass.cpp b/libcxx/test/std/language.support/support.dynamic/alloc.errors/set.new.handler/set_new_handler.pass.cpp
index 37c477f13120d3f060a20d63cecf3764e62680d0..cff382b0ee31cf24bddc5885d1d554a693a7fbaa 100644
--- a/libcxx/test/std/language.support/support.dynamic/alloc.errors/set.new.handler/set_new_handler.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/alloc.errors/set.new.handler/set_new_handler.pass.cpp
@@ -14,8 +14,10 @@
 void f1() {}
 void f2() {}
 
-int main()
+int main(int, char**)
 {
     assert(std::set_new_handler(f1) == 0);
     assert(std::set_new_handler(f2) == f1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/delete_align_val_t_replace.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/delete_align_val_t_replace.pass.cpp
index de09a75557abe40369155a7329321f858744e529..0a5265861b616f1b799ad935307509eca0a6aa63 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/delete_align_val_t_replace.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/delete_align_val_t_replace.pass.cpp
@@ -83,7 +83,7 @@ void operator delete [] (void* p, std::align_val_t) TEST_NOEXCEPT
 struct alignas(OverAligned) A {};
 struct alignas(std::max_align_t) B {};
 
-int main()
+int main(int, char**)
 {
     reset();
     {
@@ -113,4 +113,6 @@ int main()
         assert(0 == unsized_delete_nothrow_called);
         assert(1 == aligned_delete_called);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t.pass.cpp
index bd99495e5737bfbfc6650e87bcb836d46751db7a..e303c820847fb013eeb7da1a9d44ab159eeb3399 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t.pass.cpp
@@ -90,7 +90,7 @@ void test_throw_max_size() {
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
         A* ap = new A[2];
@@ -103,4 +103,6 @@ int main()
     {
         test_throw_max_size();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t_nothrow.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t_nothrow.pass.cpp
index a8367876903a0e408f1aab4ac4a254a7c6e797f1..ed7a53743f0efeca7ec15605fd60927ea51730fb 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t_nothrow.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t_nothrow.pass.cpp
@@ -92,7 +92,7 @@ void test_max_alloc() {
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
         A* ap = new(std::nothrow) A[3];
@@ -105,4 +105,6 @@ int main()
     {
         test_max_alloc();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t_nothrow_replace.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t_nothrow_replace.pass.cpp
index 5fbcc5ce753b51ac168b8c2d72687f523ac0c854..49aa2bce3ea298b508e0fb40d298f8517b3f0c09 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t_nothrow_replace.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t_nothrow_replace.pass.cpp
@@ -86,7 +86,7 @@ void  operator delete[](void* p, std::align_val_t a) TEST_NOEXCEPT
     --new_called;
 }
 
-int main()
+int main(int, char**)
 {
     {
         A* ap = new (std::nothrow) A[2];
@@ -106,4 +106,6 @@ int main()
         assert(!new_called);
         assert(!B_constructed);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t_replace.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t_replace.pass.cpp
index 40ba48dec53c527f925a85163ff9c7b12ea26d4f..cb9a2ef7f6ca8793ef2fede5831e326bb632d2a1 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t_replace.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t_replace.pass.cpp
@@ -66,7 +66,7 @@ void  operator delete[](void* p, std::align_val_t) TEST_NOEXCEPT
 }
 
 
-int main()
+int main(int, char**)
 {
     {
         A* ap = new A[3];
@@ -85,4 +85,6 @@ int main()
         delete [] bp;
         assert(!new_called);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_array.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_array.pass.cpp
index 8365b053c5d5e9017a4fdc5ba906bcf72cc62e55..55dc5c7533403d3dd6f1a1424c86adeb9c1a0e67 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_array.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_array.pass.cpp
@@ -34,7 +34,7 @@ struct A
     ~A() {--A_constructed;}
 };
 
-int main()
+int main(int, char**)
 {
 #ifndef TEST_HAS_NO_EXCEPTIONS
     std::set_new_handler(my_new_handler);
@@ -60,4 +60,6 @@ int main()
     delete [] ap;
     DoNotOptimize(ap);
     assert(A_constructed == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_array_nothrow.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_array_nothrow.pass.cpp
index 3effc7ea3ec0e0b8c096b4864b7e49954ed2f009..b4d8aa3498605336012eeef4faf3552a629974ab 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_array_nothrow.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_array_nothrow.pass.cpp
@@ -34,7 +34,7 @@ struct A
     ~A() {--A_constructed;}
 };
 
-int main()
+int main(int, char**)
 {
     std::set_new_handler(my_new_handler);
 #ifndef TEST_HAS_NO_EXCEPTIONS
@@ -59,4 +59,6 @@ int main()
     delete [] ap;
     DoNotOptimize(ap);
     assert(A_constructed == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_array_nothrow_replace.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_array_nothrow_replace.pass.cpp
index a28f7f4f15334e7be11494866a6702a10e4062fa..4d90aa9a3fe0bfacff9987a0e24babf71b7cea85 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_array_nothrow_replace.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_array_nothrow_replace.pass.cpp
@@ -43,7 +43,7 @@ struct A
     ~A() {--A_constructed;}
 };
 
-int main()
+int main(int, char**)
 {
     A *ap = new (std::nothrow) A[3];
     DoNotOptimize(ap);
@@ -54,4 +54,6 @@ int main()
     DoNotOptimize(ap);
     assert(A_constructed == 0);
     assert(!new_called);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_array_replace.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_array_replace.pass.cpp
index 4ea28241c079dd214d9edecd94cf06b5894b1130..e705fc3b499f5f6b71f74822aefbcdc9296ccbf0 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_array_replace.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_array_replace.pass.cpp
@@ -44,7 +44,7 @@ struct A
     ~A() {--A_constructed;}
 };
 
-int main()
+int main(int, char**)
 {
     A *ap = new A[3];
     DoNotOptimize(ap);
@@ -55,4 +55,6 @@ int main()
     DoNotOptimize(ap);
     assert(A_constructed == 0);
     assert(new_called == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_size.sh.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_size.sh.cpp
index 482a27e9cf688207d8ba4a0549dece1443c4c15f..a04ceb6ad42eefa2465cde69c73ff64ccea92f50 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_size.sh.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_size.sh.cpp
@@ -19,7 +19,9 @@
 
 #include <new>
 
-int main ()
+int main(int, char**)
 {
     ::operator new[](4);  // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_size_align.sh.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_size_align.sh.cpp
index 6183c0c2ce3b1f214c4dabbfd418f5cd60902bfd..e2a61591ad2b5cd664365b12a53bada4e82ea8b8 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_size_align.sh.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_size_align.sh.cpp
@@ -19,7 +19,9 @@
 
 #include <new>
 
-int main ()
+int main(int, char**)
 {
     ::operator new[](4, std::align_val_t{4});  // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_size_align_nothrow.sh.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_size_align_nothrow.sh.cpp
index 1f39219090b5cf64e964e407be33530e7f45aea7..5ad81863d4d8253f99f16ac23fc6c9f56b1ff479 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_size_align_nothrow.sh.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_size_align_nothrow.sh.cpp
@@ -19,7 +19,9 @@
 
 #include <new>
 
-int main ()
+int main(int, char**)
 {
     ::operator new[](4, std::align_val_t{4}, std::nothrow);  // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_size_nothrow.sh.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_size_nothrow.sh.cpp
index 39de421c283becf3374941125a2d060309fcef74..53af2c764c005a4a30b6663259d5de3a28c1c207 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_size_nothrow.sh.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_size_nothrow.sh.cpp
@@ -19,7 +19,9 @@
 
 #include <new>
 
-int main ()
+int main(int, char**)
 {
     ::operator new[](4, std::nothrow);  // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/sized_delete_array11.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/sized_delete_array11.pass.cpp
index 686ef66bab85742d7ec34a145028d9a0a3592ee3..e1a545cc98344abb4198a7825e55e81cca5ce81c 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/sized_delete_array11.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/sized_delete_array11.pass.cpp
@@ -54,7 +54,7 @@ void operator delete[](void* p, std::size_t) TEST_NOEXCEPT
 //   selected.
 struct A { ~A() {} };
 
-int main()
+int main(int, char**)
 {
 
     A* x = new A[3];
@@ -66,4 +66,6 @@ int main()
     assert(1 == unsized_delete_called);
     assert(0 == sized_delete_called);
     assert(0 == unsized_delete_nothrow_called);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/sized_delete_array14.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/sized_delete_array14.pass.cpp
index 773a9b9928d19ca86aac92f6d894b5efbeb56ba2..d69c28be72b511d2e842647fd63e472b3cffce09 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/sized_delete_array14.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/sized_delete_array14.pass.cpp
@@ -59,7 +59,7 @@ void operator delete[](void* p, std::size_t) TEST_NOEXCEPT
 //   selected.
 struct A { ~A() {} };
 
-int main()
+int main(int, char**)
 {
     A* x = new A[3];
     assert(0 == unsized_delete_called);
@@ -70,4 +70,6 @@ int main()
     assert(0 == unsized_delete_called);
     assert(0 == unsized_delete_nothrow_called);
     assert(1 == sized_delete_called);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/sized_delete_array_calls_unsized_delete_array.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/sized_delete_array_calls_unsized_delete_array.pass.cpp
index 2d845e6010d4e3b8adc60290c6258ad3cca52fa6..026250daeee8984bd04b165b725c1f7172983eef 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/sized_delete_array_calls_unsized_delete_array.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/sized_delete_array_calls_unsized_delete_array.pass.cpp
@@ -45,7 +45,7 @@ void operator delete[](void* p, const std::nothrow_t&) TEST_NOEXCEPT
 //   selected.
 struct A { ~A() {} };
 
-int main()
+int main(int, char**)
 {
     A *x = new A[3];
     DoNotOptimize(x);
@@ -56,4 +56,6 @@ int main()
     DoNotOptimize(x);
     assert(1 == delete_called);
     assert(0 == delete_nothrow_called);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/sized_delete_array_fsizeddeallocation.sh.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/sized_delete_array_fsizeddeallocation.sh.cpp
index a077fb7cec60349bdd4651e3ab6d509ba89b5af0..41739c0ccdc7f5933ea70c9e0501e93d2f100883 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/sized_delete_array_fsizeddeallocation.sh.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/sized_delete_array_fsizeddeallocation.sh.cpp
@@ -73,7 +73,7 @@ void operator delete[](void* p, std::size_t) TEST_NOEXCEPT
 //   selected.
 struct A { ~A() {} };
 
-int main()
+int main(int, char**)
 {
     A* x = new A[3];
     assert(0 == unsized_delete_called);
@@ -84,4 +84,6 @@ int main()
     assert(0 == unsized_delete_called);
     assert(0 == unsized_delete_nothrow_called);
     assert(1 == sized_delete_called);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.dataraces/not_testable.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.dataraces/not_testable.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.dataraces/not_testable.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.dataraces/not_testable.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.placement/new.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.placement/new.pass.cpp
index 3cd5e12458fb035105badde0c800072386498205..8256b93185dfd0232184e7f1484085050fde414d 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.placement/new.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.placement/new.pass.cpp
@@ -19,11 +19,13 @@ struct A
     ~A() {--A_constructed;}
 };
 
-int main()
+int main(int, char**)
 {
     char buf[sizeof(A)];
 
     A* ap = new(buf) A;
     assert((char*)ap == buf);
     assert(A_constructed == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.placement/new_array.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.placement/new_array.pass.cpp
index 671a3cc050f9d748bedfb3b911df6da014794727..8a78df6bffb306263a4b99dc878a6dd47fa93b35 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.placement/new_array.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.placement/new_array.pass.cpp
@@ -19,7 +19,7 @@ struct A
     ~A() {--A_constructed;}
 };
 
-int main()
+int main(int, char**)
 {
     const std::size_t Size = 3;
     // placement new might require additional space.
@@ -30,4 +30,6 @@ int main()
     assert((char*)ap >= buf);
     assert((char*)ap < (buf + ExtraSize));
     assert(A_constructed == Size);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.placement/new_array_ptr.fail.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.placement/new_array_ptr.fail.cpp
index b7b17e196e88beb7937846ce4415ddc6844c1d01..4cba717dba80593df1eeaa8a1617ee9c03fcbdda 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.placement/new_array_ptr.fail.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.placement/new_array_ptr.fail.cpp
@@ -18,8 +18,10 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     char buffer[100];
     ::operator new[](4, buffer);  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.placement/new_ptr.fail.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.placement/new_ptr.fail.cpp
index 7b5eb19d92caccc797530c42c0959714f9c9c9c7..05a9b244c1e454a6b02ccf289bd94eb8cb27c789 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.placement/new_ptr.fail.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.placement/new_ptr.fail.cpp
@@ -18,8 +18,10 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     char buffer[100];
     ::operator new(4, buffer);  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/delete_align_val_t_replace.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/delete_align_val_t_replace.pass.cpp
index 63e797480b13a59189e42623f2980bf5e9916afd..22abcba05220d58c4f2b98c70b8faadfef529c55 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/delete_align_val_t_replace.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/delete_align_val_t_replace.pass.cpp
@@ -82,7 +82,7 @@ void operator delete(void* p, std::align_val_t) TEST_NOEXCEPT
 struct alignas(OverAligned) A {};
 struct alignas(std::max_align_t) B {};
 
-int main()
+int main(int, char**)
 {
     reset();
     {
@@ -112,4 +112,6 @@ int main()
         assert(0 == unsized_delete_nothrow_called);
         assert(1 == aligned_delete_called);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new.pass.cpp
index 3c73738d6fd832590c0d05ed133e9fba499e7363..448da1717900e209027601b512c8c53ce6e95fe0 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new.pass.cpp
@@ -34,7 +34,7 @@ struct A
     ~A() {A_constructed = false;}
 };
 
-int main()
+int main(int, char**)
 {
 #ifndef TEST_HAS_NO_EXCEPTIONS
     std::set_new_handler(my_new_handler);
@@ -58,4 +58,6 @@ int main()
     assert(A_constructed);
     delete ap;
     assert(!A_constructed);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t.pass.cpp
index d0d4b98aee46bc2100cb48a8cca7b887b5b36e80..0d96db5de485d355cb85f53c04c4ff7f6ae5181b 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t.pass.cpp
@@ -90,7 +90,7 @@ void test_throw_max_size() {
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
         A* ap = new A;
@@ -103,4 +103,6 @@ int main()
     {
         test_throw_max_size();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t_nothrow.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t_nothrow.pass.cpp
index d0990c0586b47942504175a12949fb772da3b62c..4b621f78a726a8384b652048ba0d32e9bce5194f 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t_nothrow.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t_nothrow.pass.cpp
@@ -92,7 +92,7 @@ void test_max_alloc() {
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
         A* ap = new(std::nothrow) A;
@@ -105,4 +105,6 @@ int main()
     {
         test_max_alloc();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t_nothrow_replace.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t_nothrow_replace.pass.cpp
index fa8dc13cf6496e04d41a95b851a5cfd6c36ba89d..892eac2058265b605e77bd980a0238460c17281c 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t_nothrow_replace.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t_nothrow_replace.pass.cpp
@@ -88,7 +88,7 @@ void  operator delete(void* p, std::align_val_t a) TEST_NOEXCEPT
 }
 
 
-int main()
+int main(int, char**)
 {
     {
         A* ap = new (std::nothrow) A;
@@ -108,4 +108,6 @@ int main()
         assert(!new_called);
         assert(!B_constructed);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t_replace.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t_replace.pass.cpp
index d37ca28f03b232b9b63931bfccb3c87d5cab0a3d..32c27d5899ec91d8f49328090642c2c3088e6e78 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t_replace.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t_replace.pass.cpp
@@ -66,7 +66,7 @@ void  operator delete(void* p, std::align_val_t) TEST_NOEXCEPT
 }
 
 
-int main()
+int main(int, char**)
 {
     {
         A* ap = new A;
@@ -85,4 +85,6 @@ int main()
         delete bp;
         assert(!new_called);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_nothrow.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_nothrow.pass.cpp
index 6d391645f112c319e314aa6702e3faa8f2bf2e1f..dfdf7d77e801634de652e5781cd01c276bd5932b 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_nothrow.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_nothrow.pass.cpp
@@ -34,7 +34,7 @@ struct A
     ~A() {A_constructed = false;}
 };
 
-int main()
+int main(int, char**)
 {
     std::set_new_handler(my_new_handler);
 #ifndef TEST_HAS_NO_EXCEPTIONS
@@ -56,4 +56,6 @@ int main()
     assert(A_constructed);
     delete ap;
     assert(!A_constructed);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_nothrow_replace.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_nothrow_replace.pass.cpp
index b4217525fe6602dd8682d5c65afb14028808133e..1f186d8b3d17469d1635f3b8c31003f850e2bced 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_nothrow_replace.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_nothrow_replace.pass.cpp
@@ -43,7 +43,7 @@ struct A
     ~A() {A_constructed = false;}
 };
 
-int main()
+int main(int, char**)
 {
     A *ap = new (std::nothrow) A;
     DoNotOptimize(ap);
@@ -54,4 +54,6 @@ int main()
     DoNotOptimize(ap);
     assert(!A_constructed);
     assert(!new_called);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_replace.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_replace.pass.cpp
index 300843b2fa015c380d62fa5d9f133df98badc8cd..4854c2fb776197399f96a590f5cc9a24a8849733 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_replace.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_replace.pass.cpp
@@ -42,7 +42,7 @@ struct A
     ~A() {A_constructed = false;}
 };
 
-int main()
+int main(int, char**)
 {
     A *ap = new A;
     DoNotOptimize(ap);
@@ -53,4 +53,6 @@ int main()
     DoNotOptimize(ap);
     assert(!A_constructed);
     assert(!new_called);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_size.fail.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_size.fail.cpp
index 5042a8d1e497e00db36eceaef59118f85dc81670..4769933d399a1e855ae5c748e968de239ac72ae1 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_size.fail.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_size.fail.cpp
@@ -18,7 +18,9 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     ::operator new(4);  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_size_align.sh.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_size_align.sh.cpp
index e22ea0fdd20fe3c3f22f58a658f2471ff61a9445..a0d99c76d0723520326c50a33bfd40c1ce5ebb06 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_size_align.sh.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_size_align.sh.cpp
@@ -19,7 +19,9 @@
 
 #include <new>
 
-int main ()
+int main(int, char**)
 {
     ::operator new(4, std::align_val_t{4});  // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_size_align_nothrow.sh.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_size_align_nothrow.sh.cpp
index 617eeae3cfd0ac1132da559ca128d796a9243b41..54b25ac5589ac32d9382abc01ebdf90d5365d514 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_size_align_nothrow.sh.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_size_align_nothrow.sh.cpp
@@ -19,7 +19,9 @@
 
 #include <new>
 
-int main ()
+int main(int, char**)
 {
     ::operator new(4, std::align_val_t{4}, std::nothrow);  // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_size_nothrow.fail.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_size_nothrow.fail.cpp
index dd51ad54af9303dbb2b203788acd27333bd8a72e..a0bfa8b7f921f70a88fdce59a498b45d9a1c52eb 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_size_nothrow.fail.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_size_nothrow.fail.cpp
@@ -18,7 +18,9 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     ::operator new(4, std::nothrow);  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/sized_delete11.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/sized_delete11.pass.cpp
index 779d7b2acfe7023d5e86a3fab375de49cd8f9258..69f8bce27671577830f590199c88be2797282745 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/sized_delete11.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/sized_delete11.pass.cpp
@@ -43,7 +43,7 @@ void operator delete(void* p, std::size_t) TEST_NOEXCEPT
     std::free(p);
 }
 
-int main()
+int main(int, char**)
 {
     int *x = new int(42);
     DoNotOptimize(x);
@@ -56,4 +56,6 @@ int main()
     assert(1 == unsized_delete_called);
     assert(0 == sized_delete_called);
     assert(0 == unsized_delete_nothrow_called);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/sized_delete14.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/sized_delete14.pass.cpp
index bed5cc2323a0be254a0c4eede82e5b6b976a5021..deb17d1ae7412538c07ef5fda4ec4cc1ec130a87 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/sized_delete14.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/sized_delete14.pass.cpp
@@ -48,7 +48,7 @@ void operator delete(void* p, std::size_t) TEST_NOEXCEPT
     std::free(p);
 }
 
-int main()
+int main(int, char**)
 {
     int *x = new int(42);
     DoNotOptimize(x);
@@ -61,4 +61,6 @@ int main()
     assert(0 == unsized_delete_called);
     assert(1 == sized_delete_called);
     assert(0 == unsized_delete_nothrow_called);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/sized_delete_calls_unsized_delete.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/sized_delete_calls_unsized_delete.pass.cpp
index 9c54750bde17c6568770b967fdb2330d4736fa26..fbc9cf070bcbaab0e6c37de2a1d14193f4dbb8ac 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/sized_delete_calls_unsized_delete.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/sized_delete_calls_unsized_delete.pass.cpp
@@ -34,7 +34,7 @@ void operator delete(void* p, const std::nothrow_t&) TEST_NOEXCEPT
     std::free(p);
 }
 
-int main()
+int main(int, char**)
 {
     int *x = new int(42);
     DoNotOptimize(x);
@@ -45,4 +45,6 @@ int main()
     DoNotOptimize(x);
     assert(1 == delete_called);
     assert(0 == delete_nothrow_called);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/sized_delete_fsizeddeallocation.sh.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/sized_delete_fsizeddeallocation.sh.cpp
index be208b43165d846646abd9be5777d49c5c87c11d..3d62040cbe81d85cdecfec5347025b6a4cec9780 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/sized_delete_fsizeddeallocation.sh.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/sized_delete_fsizeddeallocation.sh.cpp
@@ -61,7 +61,7 @@ void operator delete(void* p, std::size_t) TEST_NOEXCEPT
     std::free(p);
 }
 
-int main()
+int main(int, char**)
 {
     int *x = new int(42);
     DoNotOptimize(x);
@@ -74,4 +74,6 @@ int main()
     assert(1 == sized_delete_called);
     assert(0 == unsized_delete_called);
     assert(0 == unsized_delete_nothrow_called);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/nothing_to_do.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/ptr.launder/launder.nodiscard.fail.cpp b/libcxx/test/std/language.support/support.dynamic/ptr.launder/launder.nodiscard.fail.cpp
index 3f105410bad6c1a6cba8bb63da5883dd4e325437..e7252395d35313e8b6a5af05689af22116db2c07 100644
--- a/libcxx/test/std/language.support/support.dynamic/ptr.launder/launder.nodiscard.fail.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/ptr.launder/launder.nodiscard.fail.cpp
@@ -19,8 +19,10 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     int *p = nullptr;
     std::launder(p);  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/ptr.launder/launder.pass.cpp b/libcxx/test/std/language.support/support.dynamic/ptr.launder/launder.pass.cpp
index c3d2271834fa81294cc634829a558182af2b3f3b..f9d4da37146f3862ced79b9a817ee71389f9d6a4 100644
--- a/libcxx/test/std/language.support/support.dynamic/ptr.launder/launder.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/ptr.launder/launder.pass.cpp
@@ -20,7 +20,7 @@
 constexpr int gi = 5;
 constexpr float gf = 8.f;
 
-int main() {
+int main(int, char**) {
     static_assert(std::launder(&gi) == &gi, "" );
     static_assert(std::launder(&gf) == &gf, "" );
 
@@ -31,4 +31,6 @@ int main() {
 
     assert(std::launder(i) == i);
     assert(std::launder(f) == f);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.dynamic/ptr.launder/launder.types.fail.cpp b/libcxx/test/std/language.support/support.dynamic/ptr.launder/launder.types.fail.cpp
index f8fd12f1cda485f1e24603d0d19c4bee1152f4ed..d97d00194e2c5ffb37ac22e9466149f20f3293a8 100644
--- a/libcxx/test/std/language.support/support.dynamic/ptr.launder/launder.types.fail.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/ptr.launder/launder.types.fail.cpp
@@ -21,7 +21,7 @@
 
 void foo() {}
 
-int main ()
+int main(int, char**)
 {
     void *p = nullptr;
     (void) std::launder((               void *) nullptr);
@@ -32,4 +32,6 @@ int main ()
 
     (void) std::launder(foo);                              // expected-error-re@new:* 1 {{static_assert failed{{.*}} "can't launder functions"}}
     // expected-error@new:* 0-1 {{function pointer argument to '__builtin_launder' is not allowed}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.exception/bad.exception/bad_exception.pass.cpp b/libcxx/test/std/language.support/support.exception/bad.exception/bad_exception.pass.cpp
index c4e1cc7a1abc7f5e49f43280aea309bf68492643..e5f4fbe6dcf9c0243449acddf1dc3daeccd1a041 100644
--- a/libcxx/test/std/language.support/support.exception/bad.exception/bad_exception.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/bad.exception/bad_exception.pass.cpp
@@ -12,7 +12,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::exception, std::bad_exception>::value),
                  "std::is_base_of<std::exception, std::bad_exception>::value");
@@ -23,4 +23,6 @@ int main()
     b2 = b;
     const char* w = b2.what();
     assert(w);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.exception/except.nested/assign.pass.cpp b/libcxx/test/std/language.support/support.exception/except.nested/assign.pass.cpp
index c03f4bbfd4fba1806efb904bf6338debbad0d6e9..972649579b1e82f5730811f256137191f252c8b0 100644
--- a/libcxx/test/std/language.support/support.exception/except.nested/assign.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/except.nested/assign.pass.cpp
@@ -26,7 +26,7 @@ public:
     friend bool operator==(const A& x, const A& y) {return x.data_ == y.data_;}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::nested_exception e0;
@@ -59,4 +59,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.exception/except.nested/ctor_copy.pass.cpp b/libcxx/test/std/language.support/support.exception/except.nested/ctor_copy.pass.cpp
index cc8c998562284c1d1cdc0cfe59c2b236717e6e2a..9d65f5fb22bdbff9aa7508fd0d27ea167faef2a4 100644
--- a/libcxx/test/std/language.support/support.exception/except.nested/ctor_copy.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/except.nested/ctor_copy.pass.cpp
@@ -26,7 +26,7 @@ public:
     friend bool operator==(const A& x, const A& y) {return x.data_ == y.data_;}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::nested_exception e0;
@@ -57,4 +57,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.exception/except.nested/ctor_default.pass.cpp b/libcxx/test/std/language.support/support.exception/except.nested/ctor_default.pass.cpp
index 5aa762cf7cab6d165af7361e0870749684e0a201..a96c3d015a18a4f29e9a88a5bf909360f79e1815 100644
--- a/libcxx/test/std/language.support/support.exception/except.nested/ctor_default.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/except.nested/ctor_default.pass.cpp
@@ -26,7 +26,7 @@ public:
     friend bool operator==(const A& x, const A& y) {return x.data_ == y.data_;}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::nested_exception e;
@@ -55,4 +55,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.exception/except.nested/rethrow_if_nested.pass.cpp b/libcxx/test/std/language.support/support.exception/except.nested/rethrow_if_nested.pass.cpp
index 426ea55bff939be2e250c3fd738cf6d9a78c83be..01ef7ade7c2b6d649daa21158c68562c848569b1 100644
--- a/libcxx/test/std/language.support/support.exception/except.nested/rethrow_if_nested.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/except.nested/rethrow_if_nested.pass.cpp
@@ -56,7 +56,7 @@ class E1 : public std::nested_exception {};
 class E2 : public std::nested_exception {};
 class E : public E1, public E2 {};
 
-int main()
+int main(int, char**)
 {
     {
         try
@@ -131,4 +131,6 @@ int main()
         }
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.exception/except.nested/rethrow_nested.pass.cpp b/libcxx/test/std/language.support/support.exception/except.nested/rethrow_nested.pass.cpp
index ba81b8fe3af913e9dee10aaf312f6bdd19872a88..204c3b567e70cc1057f754dd1380429135d130ef 100644
--- a/libcxx/test/std/language.support/support.exception/except.nested/rethrow_nested.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/except.nested/rethrow_nested.pass.cpp
@@ -31,7 +31,7 @@ void go_quietly()
     std::exit(0);
 }
 
-int main()
+int main(int, char**)
 {
     {
         try
@@ -67,4 +67,6 @@ int main()
             assert(false);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.exception/except.nested/throw_with_nested.pass.cpp b/libcxx/test/std/language.support/support.exception/except.nested/throw_with_nested.pass.cpp
index c0bc423b01b1d166d64f2881a2e730e4034c2960..b63053c3304f5fb68a8a67691c194c0d3d44d5a2 100644
--- a/libcxx/test/std/language.support/support.exception/except.nested/throw_with_nested.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/except.nested/throw_with_nested.pass.cpp
@@ -42,7 +42,7 @@ public:
 struct Final final {};
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         try
@@ -128,4 +128,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.exception/exception.terminate/nothing_to_do.pass.cpp b/libcxx/test/std/language.support/support.exception/exception.terminate/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/language.support/support.exception/exception.terminate/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/exception.terminate/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.exception/exception.terminate/set.terminate/get_terminate.pass.cpp b/libcxx/test/std/language.support/support.exception/exception.terminate/set.terminate/get_terminate.pass.cpp
index 2ec624ba6545f5e83edb5061fb97a4686df96ce1..851d93bc0c8aee11ed796b297c5a308d730aab54 100644
--- a/libcxx/test/std/language.support/support.exception/exception.terminate/set.terminate/get_terminate.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/exception.terminate/set.terminate/get_terminate.pass.cpp
@@ -15,10 +15,12 @@
 void f1() {}
 void f2() {}
 
-int main()
+int main(int, char**)
 {
     std::set_terminate(f1);
     assert(std::get_terminate() == f1);
     std::set_terminate(f2);
     assert(std::get_terminate() == f2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.exception/exception.terminate/set.terminate/set_terminate.pass.cpp b/libcxx/test/std/language.support/support.exception/exception.terminate/set.terminate/set_terminate.pass.cpp
index 9eae3a45edfbf882173d247faf0e2f1063aebae6..e4464b9afc1a7a8dfda06a628e81f44d7c06fb3a 100644
--- a/libcxx/test/std/language.support/support.exception/exception.terminate/set.terminate/set_terminate.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/exception.terminate/set.terminate/set_terminate.pass.cpp
@@ -15,8 +15,10 @@
 void f1() {}
 void f2() {}
 
-int main()
+int main(int, char**)
 {
     std::set_terminate(f1);
     assert(std::set_terminate(f2) == f1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.exception/exception.terminate/terminate.handler/terminate_handler.pass.cpp b/libcxx/test/std/language.support/support.exception/exception.terminate/terminate.handler/terminate_handler.pass.cpp
index 8f889beee8f5892365f9e4f099854c93a958d2f7..2519f0bc9cebf071d03e9ed3c67bf363ed1a6f2d 100644
--- a/libcxx/test/std/language.support/support.exception/exception.terminate/terminate.handler/terminate_handler.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/exception.terminate/terminate.handler/terminate_handler.pass.cpp
@@ -14,9 +14,11 @@
 
 void f() {}
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::terminate_handler, void(*)()>::value), "");
     std::terminate_handler p = f;
     assert(p == &f);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.exception/exception.terminate/terminate/terminate.pass.cpp b/libcxx/test/std/language.support/support.exception/exception.terminate/terminate/terminate.pass.cpp
index 431ad8bf943b71a3db60296fa1f56d09b1635862..4243fb5cadf053c2da78d272d1c3a084ee8485ba 100644
--- a/libcxx/test/std/language.support/support.exception/exception.terminate/terminate/terminate.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/exception.terminate/terminate/terminate.pass.cpp
@@ -17,9 +17,11 @@ void f1()
     std::exit(0);
 }
 
-int main()
+int main(int, char**)
 {
     std::set_terminate(f1);
     std::terminate();
     assert(false);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.exception/exception/exception.pass.cpp b/libcxx/test/std/language.support/support.exception/exception/exception.pass.cpp
index bfb27418f531f70c5696feed5f3c9ad4c6fb55c0..893a7d5b3631413562ff4b845dbba7adcc356520 100644
--- a/libcxx/test/std/language.support/support.exception/exception/exception.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/exception/exception.pass.cpp
@@ -12,7 +12,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     static_assert(std::is_polymorphic<std::exception>::value,
                  "std::is_polymorphic<std::exception>::value");
@@ -21,4 +21,6 @@ int main()
     b2 = b;
     const char* w = b2.what();
     assert(w);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.exception/propagation/current_exception.pass.cpp b/libcxx/test/std/language.support/support.exception/propagation/current_exception.pass.cpp
index 3c265d8bb887db2dc3f19be6f4c40f132d6607e4..c95368163d41ebcfb2b219285e2501aeee1fc3a9 100644
--- a/libcxx/test/std/language.support/support.exception/propagation/current_exception.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/propagation/current_exception.pass.cpp
@@ -29,7 +29,7 @@ struct A
 
 int A::constructed = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::exception_ptr p = std::current_exception();
@@ -270,4 +270,6 @@ int main()
         assert(p != nullptr);
     }
     assert(A::constructed == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.exception/propagation/exception_ptr.pass.cpp b/libcxx/test/std/language.support/support.exception/propagation/exception_ptr.pass.cpp
index 39f2d6014dcd2d37cb2e644758f98230d0a42296..164e7774be9e31d898440f92b8dfa9a650c3132c 100644
--- a/libcxx/test/std/language.support/support.exception/propagation/exception_ptr.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/propagation/exception_ptr.pass.cpp
@@ -15,7 +15,7 @@
 #include <exception>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::exception_ptr p;
     assert(p == nullptr);
@@ -30,4 +30,6 @@ int main()
     assert(p3 == nullptr);
     p3 = nullptr;
     assert(p3 == nullptr);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.exception/propagation/make_exception_ptr.pass.cpp b/libcxx/test/std/language.support/support.exception/propagation/make_exception_ptr.pass.cpp
index 3db951d281f37e8af0e21e2d7a239148b4f87fa6..b26212fd136b4bb0f89254acf592ee8ba93eed4b 100644
--- a/libcxx/test/std/language.support/support.exception/propagation/make_exception_ptr.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/propagation/make_exception_ptr.pass.cpp
@@ -26,7 +26,7 @@ struct A
 
 int A::constructed = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::exception_ptr p = std::make_exception_ptr(A(5));
@@ -52,4 +52,6 @@ int main()
         assert(A::constructed == 0);
     }
     assert(A::constructed == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.exception/propagation/rethrow_exception.pass.cpp b/libcxx/test/std/language.support/support.exception/propagation/rethrow_exception.pass.cpp
index ab2df72e8e83f33e353f45d86f6d829f5b7ed5de..015dbef224f7d325d1a14b24e5dc358e647ae8b6 100644
--- a/libcxx/test/std/language.support/support.exception/propagation/rethrow_exception.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/propagation/rethrow_exception.pass.cpp
@@ -26,7 +26,7 @@ struct A
 
 int A::constructed = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::exception_ptr p;
@@ -60,4 +60,6 @@ int main()
         assert(A::constructed == 0);
     }
     assert(A::constructed == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.exception/uncaught/uncaught_exception.pass.cpp b/libcxx/test/std/language.support/support.exception/uncaught/uncaught_exception.pass.cpp
index 29087eb153f9689f5cfe19ba7fb6ce845688445e..61cfc8f11c1077ec72d5c410600105944d5fe879 100644
--- a/libcxx/test/std/language.support/support.exception/uncaught/uncaught_exception.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/uncaught/uncaught_exception.pass.cpp
@@ -29,7 +29,7 @@ struct B
     }
 };
 
-int main()
+int main(int, char**)
 {
     try
     {
@@ -42,4 +42,6 @@ int main()
         assert(!std::uncaught_exception());
     }
     assert(!std::uncaught_exception());
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.exception/uncaught/uncaught_exceptions.pass.cpp b/libcxx/test/std/language.support/support.exception/uncaught/uncaught_exceptions.pass.cpp
index bab33d837e5fd5a1bbc5b80bbd7fc8ff17888609..c25e4d2e069ff76141c41f0d758b712135e7f6b0 100644
--- a/libcxx/test/std/language.support/support.exception/uncaught/uncaught_exceptions.pass.cpp
+++ b/libcxx/test/std/language.support/support.exception/uncaught/uncaught_exceptions.pass.cpp
@@ -41,7 +41,7 @@ struct Outer {
     int d_;
 };
 
-int main () {
+int main(int, char**) {
     assert(std::uncaught_exceptions() == 0);
     {
     Outer o(0);
@@ -58,4 +58,6 @@ int main () {
         }
     }
     assert(std::uncaught_exceptions() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.general/nothing_to_do.pass.cpp b/libcxx/test/std/language.support/support.general/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/language.support/support.general/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/language.support/support.general/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.initlist/include_cxx03.pass.cpp b/libcxx/test/std/language.support/support.initlist/include_cxx03.pass.cpp
index 343da95f406716756eecda0aa25c245a815764a3..282636ed05b812fc76e89e6f542a33a64a52bc19 100644
--- a/libcxx/test/std/language.support/support.initlist/include_cxx03.pass.cpp
+++ b/libcxx/test/std/language.support/support.initlist/include_cxx03.pass.cpp
@@ -12,6 +12,8 @@
 
 #include <initializer_list>
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.initlist/support.initlist.access/access.pass.cpp b/libcxx/test/std/language.support/support.initlist/support.initlist.access/access.pass.cpp
index ff532fbf26729fe7f628c8d271f7c7ad66a20c89..097f21a5c69779f18c2defaee035e1f072fda721 100644
--- a/libcxx/test/std/language.support/support.initlist/support.initlist.access/access.pass.cpp
+++ b/libcxx/test/std/language.support/support.initlist/support.initlist.access/access.pass.cpp
@@ -51,11 +51,13 @@ struct B
 
 #endif  // TEST_STD_VER > 11
 
-int main()
+int main(int, char**)
 {
     A test1 = {3, 2, 1};
 #if TEST_STD_VER > 11
     constexpr B test2 = {3, 2, 1};
     (void)test2;
 #endif  // TEST_STD_VER > 11
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.initlist/support.initlist.cons/default.pass.cpp b/libcxx/test/std/language.support/support.initlist/support.initlist.cons/default.pass.cpp
index dc5c5ffd47aed0b82751b664541025e403ede990..8d2e0a7e713822b6f1b9ce618c716d151ce110ca 100644
--- a/libcxx/test/std/language.support/support.initlist/support.initlist.cons/default.pass.cpp
+++ b/libcxx/test/std/language.support/support.initlist/support.initlist.cons/default.pass.cpp
@@ -19,7 +19,7 @@
 
 struct A {};
 
-int main()
+int main(int, char**)
 {
     std::initializer_list<A> il;
     assert(il.size() == 0);
@@ -28,4 +28,6 @@ int main()
     constexpr std::initializer_list<A> il2;
     static_assert(il2.size() == 0, "");
 #endif  // TEST_STD_VER > 11
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.initlist/support.initlist.range/begin_end.pass.cpp b/libcxx/test/std/language.support/support.initlist/support.initlist.range/begin_end.pass.cpp
index 61bf2708441045e289a3b963478d35415d445390..ec755bfeb98561d6a1cad59a319ee2644d87e409 100644
--- a/libcxx/test/std/language.support/support.initlist/support.initlist.range/begin_end.pass.cpp
+++ b/libcxx/test/std/language.support/support.initlist/support.initlist.range/begin_end.pass.cpp
@@ -49,11 +49,13 @@ struct B
 
 #endif  // TEST_STD_VER > 11
 
-int main()
+int main(int, char**)
 {
     A test1 = {3, 2, 1};
 #if TEST_STD_VER > 11
     constexpr B test2 = {3, 2, 1};
     (void)test2;
 #endif  // TEST_STD_VER > 11
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.initlist/types.pass.cpp b/libcxx/test/std/language.support/support.initlist/types.pass.cpp
index 9aad9b3f757c2c6c4147dfe52d08a903545961be..1b48980a2402d7873c2fd6dd56eb318299fadeb9 100644
--- a/libcxx/test/std/language.support/support.initlist/types.pass.cpp
+++ b/libcxx/test/std/language.support/support.initlist/types.pass.cpp
@@ -25,7 +25,7 @@
 
 struct A {};
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::initializer_list<A>::value_type, A>::value), "");
     static_assert((std::is_same<std::initializer_list<A>::reference, const A&>::value), "");
@@ -33,4 +33,6 @@ int main()
     static_assert((std::is_same<std::initializer_list<A>::size_type, std::size_t>::value), "");
     static_assert((std::is_same<std::initializer_list<A>::iterator, const A*>::value), "");
     static_assert((std::is_same<std::initializer_list<A>::const_iterator, const A*>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/c.limits/cfloat.pass.cpp b/libcxx/test/std/language.support/support.limits/c.limits/cfloat.pass.cpp
index ec144a03177cfe4bb630bee8c9b8443e852ccc3e..12b80adf0116927fb82e607ca525cda24d7b7729 100644
--- a/libcxx/test/std/language.support/support.limits/c.limits/cfloat.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/c.limits/cfloat.pass.cpp
@@ -178,6 +178,8 @@
 #endif
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/c.limits/climits.pass.cpp b/libcxx/test/std/language.support/support.limits/c.limits/climits.pass.cpp
index 317d5d5094f4f47498fe32d0de9ecc86ef4c559d..d124f7ca28d40df4f695bd67389586728e6c4ade 100644
--- a/libcxx/test/std/language.support/support.limits/c.limits/climits.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/c.limits/climits.pass.cpp
@@ -86,6 +86,8 @@
 #error ULLONG_MAX not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/denorm.style/check_values.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/denorm.style/check_values.pass.cpp
index 6b48dfbc3795ee27086cd96f91c82dbbd941e806..adbd102dc2038a5acea358fa0d81bfff223b6b2e 100644
--- a/libcxx/test/std/language.support/support.limits/limits/denorm.style/check_values.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/denorm.style/check_values.pass.cpp
@@ -18,7 +18,7 @@ struct two {one _[2];};
 one test(std::float_round_style);
 two test(int);
 
-int main()
+int main(int, char**)
 {
     static_assert(std::round_indeterminate == -1,
                  "std::round_indeterminate == -1");
@@ -34,4 +34,6 @@ int main()
                  "sizeof(test(std::round_to_nearest)) == 1");
     static_assert(sizeof(test(1)) == 2,
                  "sizeof(test(1)) == 2");
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/is_specialized.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/is_specialized.pass.cpp
index 4959d5f54b9d62b08884032f36c6a3f4d4ff378d..b836555afc75b17dfcd21b6dfc5ae702c0af67ce 100644
--- a/libcxx/test/std/language.support/support.limits/limits/is_specialized.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/is_specialized.pass.cpp
@@ -39,7 +39,7 @@ void test()
                  "std::numeric_limits<const volatile T>::is_specialized");
 }
 
-int main()
+int main(int, char**)
 {
     test<bool>();
     test<char>();
@@ -67,4 +67,6 @@ int main()
     test<long double>();
     static_assert(!std::numeric_limits<std::complex<double> >::is_specialized,
                  "!std::numeric_limits<std::complex<double> >::is_specialized");
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/const_data_members.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/const_data_members.pass.cpp
index 012a9a8eef33413164eb1932acfec8f70f282526..b5912130a8db59281ec6684fabd7274e2d5f1761 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/const_data_members.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/const_data_members.pass.cpp
@@ -68,7 +68,7 @@ void test(const T &) {}
 
 struct other {};
 
-int main()
+int main(int, char**)
 {
     // bool
     TEST_NUMERIC_LIMITS(bool)
@@ -205,4 +205,6 @@ int main()
     TEST_NUMERIC_LIMITS(const other)
     TEST_NUMERIC_LIMITS(volatile other)
     TEST_NUMERIC_LIMITS(const volatile other)
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/denorm_min.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/denorm_min.pass.cpp
index d67e8cbaba73b20ee7efc4a024a8f6279114dffb..4f9f62873aa1307b245b3d39f2a0415df804c27b 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/denorm_min.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/denorm_min.pass.cpp
@@ -26,7 +26,7 @@ test(T expected)
     assert(std::numeric_limits<const volatile T>::denorm_min() == expected);
 }
 
-int main()
+int main(int, char**)
 {
     test<bool>(false);
     test<char>(0);
@@ -65,4 +65,6 @@ int main()
 #if !defined(__FLT_DENORM_MIN__) && !defined(FLT_TRUE_MIN)
 #error Test has no expected values for floating point types
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/digits.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/digits.pass.cpp
index de9aa3395d6fe044d904d585f895ee5cc1a1782a..139f4821dc832154a95103a067baa72fdca64b1f 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/digits.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/digits.pass.cpp
@@ -25,7 +25,7 @@ test()
     static_assert(std::numeric_limits<const volatile T>::digits == expected, "digits test 4");
 }
 
-int main()
+int main(int, char**)
 {
     test<bool, 1>();
     test<char, std::numeric_limits<char>::is_signed ? 7 : 8>();
@@ -54,4 +54,6 @@ int main()
     test<float, FLT_MANT_DIG>();
     test<double, DBL_MANT_DIG>();
     test<long double, LDBL_MANT_DIG>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/digits10.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/digits10.pass.cpp
index 9c2fcfb17975245eaa407e2b61961d7f9d31ac16..efdfd70d79ccdea2751e0eccf8506c79f84d8e48 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/digits10.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/digits10.pass.cpp
@@ -29,7 +29,7 @@ test()
     static_assert(std::numeric_limits<const volatile T>::is_bounded, "digits10 test 8");
 }
 
-int main()
+int main(int, char**)
 {
     test<bool, 0>();
     test<char, 2>();
@@ -58,4 +58,6 @@ int main()
     test<float, FLT_DIG>();
     test<double, DBL_DIG>();
     test<long double, LDBL_DIG>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/epsilon.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/epsilon.pass.cpp
index 691bd5b2765c3d641266b728cf78b7faf6d5efb7..60a905f79bb6f3a6d2334cf46f3a54dde043d668 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/epsilon.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/epsilon.pass.cpp
@@ -26,7 +26,7 @@ test(T expected)
     assert(std::numeric_limits<const volatile T>::epsilon() == expected);
 }
 
-int main()
+int main(int, char**)
 {
     test<bool>(false);
     test<char>(0);
@@ -55,4 +55,6 @@ int main()
     test<float>(FLT_EPSILON);
     test<double>(DBL_EPSILON);
     test<long double>(LDBL_EPSILON);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/has_denorm.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/has_denorm.pass.cpp
index 05469f08c96314fbe8ee79a3fe28d8de5916f521..d5380c1a76391e5a5475ec58eac37168817b3e3c 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/has_denorm.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/has_denorm.pass.cpp
@@ -24,7 +24,7 @@ test()
     static_assert(std::numeric_limits<const volatile T>::has_denorm == expected, "has_denorm test 4");
 }
 
-int main()
+int main(int, char**)
 {
     test<bool, std::denorm_absent>();
     test<char, std::denorm_absent>();
@@ -53,4 +53,6 @@ int main()
     test<float, std::denorm_present>();
     test<double, std::denorm_present>();
     test<long double, std::denorm_present>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/has_denorm_loss.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/has_denorm_loss.pass.cpp
index 89bc78a48c239bfae6750a68c240c55d0f20058c..77e5de6ab8357d6aefebdd4496c2f39b83e8ab2a 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/has_denorm_loss.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/has_denorm_loss.pass.cpp
@@ -24,7 +24,7 @@ test()
     static_assert(std::numeric_limits<const volatile T>::has_denorm_loss == expected, "has_denorm_loss test 4");
 }
 
-int main()
+int main(int, char**)
 {
     test<bool, false>();
     test<char, false>();
@@ -53,4 +53,6 @@ int main()
     test<float, false>();
     test<double, false>();
     test<long double, false>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/has_infinity.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/has_infinity.pass.cpp
index abdd9b544eec3492f62ed49d994f139d9029306e..19d4fe29312e8228d81b11a46fbe75c6c0fdad4a 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/has_infinity.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/has_infinity.pass.cpp
@@ -24,7 +24,7 @@ test()
     static_assert(std::numeric_limits<const volatile T>::has_infinity == expected, "has_infinity test 4");
 }
 
-int main()
+int main(int, char**)
 {
     test<bool, false>();
     test<char, false>();
@@ -53,4 +53,6 @@ int main()
     test<float, true>();
     test<double, true>();
     test<long double, true>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/has_quiet_NaN.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/has_quiet_NaN.pass.cpp
index a351bcef094c908fac694a56a46c9d66eedfcf13..767df5ac27b4bc8cbdad6174a3806143495f8adb 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/has_quiet_NaN.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/has_quiet_NaN.pass.cpp
@@ -24,7 +24,7 @@ test()
     static_assert(std::numeric_limits<const volatile T>::has_quiet_NaN == expected, "has_quiet_NaN test 4");
 }
 
-int main()
+int main(int, char**)
 {
     test<bool, false>();
     test<char, false>();
@@ -53,4 +53,6 @@ int main()
     test<float, true>();
     test<double, true>();
     test<long double, true>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/has_signaling_NaN.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/has_signaling_NaN.pass.cpp
index bc74464e788113b97391da149a98d4a8ef1086d8..0908c49bc16eb7fd44a63b1ab5fca89b84c2f1c5 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/has_signaling_NaN.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/has_signaling_NaN.pass.cpp
@@ -24,7 +24,7 @@ test()
     static_assert(std::numeric_limits<const volatile T>::has_signaling_NaN == expected, "has_signaling_NaN test 4");
 }
 
-int main()
+int main(int, char**)
 {
     test<bool, false>();
     test<char, false>();
@@ -53,4 +53,6 @@ int main()
     test<float, true>();
     test<double, true>();
     test<long double, true>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/infinity.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/infinity.pass.cpp
index 924f32a6b262e1549fc1201ec1c86c490a430627..0004e4e6282c49af3c2e85665c712f94679c3750 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/infinity.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/infinity.pass.cpp
@@ -28,7 +28,7 @@ test(T expected)
 
 extern float zero;
 
-int main()
+int main(int, char**)
 {
     test<bool>(false);
     test<char>(0);
@@ -57,6 +57,8 @@ int main()
     test<float>(1.f/zero);
     test<double>(1./zero);
     test<long double>(1./zero);
+
+  return 0;
 }
 
 float zero = 0;
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/is_bounded.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/is_bounded.pass.cpp
index 8f2cdb0a78fddbc0e26c31d2f4162775a7d99e37..d509be720e7d0489adeb248358388e5b6d8d4c22 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/is_bounded.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/is_bounded.pass.cpp
@@ -24,7 +24,7 @@ test()
     static_assert(std::numeric_limits<const volatile T>::is_bounded == expected, "is_bounded test 4");
 }
 
-int main()
+int main(int, char**)
 {
     test<bool, true>();
     test<char, true>();
@@ -53,4 +53,6 @@ int main()
     test<float, true>();
     test<double, true>();
     test<long double, true>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/is_exact.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/is_exact.pass.cpp
index 2c769d87cf3ae5e83b413ea9753711b9ea0a1c66..30dbd9ea11f855b706ed9c72b78a7dd06f2f4064 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/is_exact.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/is_exact.pass.cpp
@@ -24,7 +24,7 @@ test()
     static_assert(std::numeric_limits<const volatile T>::is_exact == expected, "is_exact test 4");
 }
 
-int main()
+int main(int, char**)
 {
     test<bool, true>();
     test<char, true>();
@@ -53,4 +53,6 @@ int main()
     test<float, false>();
     test<double, false>();
     test<long double, false>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/is_iec559.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/is_iec559.pass.cpp
index c7edf178dc21ee0365ccf87b0c20462e6ff8d68c..215407d74b347bdbc509f8b4fffad7d90aa06f90 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/is_iec559.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/is_iec559.pass.cpp
@@ -24,7 +24,7 @@ test()
     static_assert(std::numeric_limits<const volatile T>::is_iec559 == expected, "is_iec559 test 4");
 }
 
-int main()
+int main(int, char**)
 {
     test<bool, false>();
     test<char, false>();
@@ -57,4 +57,6 @@ int main()
 #else
     test<long double, true>();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/is_integer.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/is_integer.pass.cpp
index 80a45fa29f8d3c699629e5ddf4d3555119e42692..66ce0cb2bad4c433fde3fc797ca50164c1387555 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/is_integer.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/is_integer.pass.cpp
@@ -24,7 +24,7 @@ test()
     static_assert(std::numeric_limits<const volatile T>::is_integer == expected, "is_integer test 4");
 }
 
-int main()
+int main(int, char**)
 {
     test<bool, true>();
     test<char, true>();
@@ -53,4 +53,6 @@ int main()
     test<float, false>();
     test<double, false>();
     test<long double, false>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/is_modulo.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/is_modulo.pass.cpp
index c364fd01bd19263fd9b8e734d82c1cd1a4f71be0..2eb2c4ba494d3789f3a66baeb55cebce81c47daa 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/is_modulo.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/is_modulo.pass.cpp
@@ -24,7 +24,7 @@ test()
     static_assert(std::numeric_limits<const volatile T>::is_modulo == expected, "is_modulo test 4");
 }
 
-int main()
+int main(int, char**)
 {
     test<bool, false>();
 //    test<char, false>(); // don't know
@@ -53,4 +53,6 @@ int main()
     test<float, false>();
     test<double, false>();
     test<long double, false>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/is_signed.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/is_signed.pass.cpp
index 08dc5eb772fdf95efcf26b81f5d4a883025cd01e..818ad4db9f47d25bdb4a5670ab57d339e9173376 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/is_signed.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/is_signed.pass.cpp
@@ -24,7 +24,7 @@ test()
     static_assert(std::numeric_limits<const volatile T>::is_signed == expected, "is_signed test 4");
 }
 
-int main()
+int main(int, char**)
 {
     test<bool, false>();
     test<char, char(-1) < char(0)>();
@@ -53,4 +53,6 @@ int main()
     test<float, true>();
     test<double, true>();
     test<long double, true>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/lowest.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/lowest.pass.cpp
index bb6ae168e72208d39a53d5956c7dbffd6ace8ee3..adf147c7069a64679ebcfe3e95233253c759bd85 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/lowest.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/lowest.pass.cpp
@@ -32,7 +32,7 @@ test(T expected)
     assert(std::numeric_limits<const volatile T>::is_bounded);
 }
 
-int main()
+int main(int, char**)
 {
     test<bool>(false);
     test<char>(CHAR_MIN);
@@ -61,4 +61,6 @@ int main()
     test<float>(-FLT_MAX);
     test<double>(-DBL_MAX);
     test<long double>(-LDBL_MAX);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/max.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/max.pass.cpp
index 0bf7237ad9ec9ea76ce188767137500103376e8d..91f353ab5e20af45e1f47f7a57b5529fcfbb4353 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/max.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/max.pass.cpp
@@ -32,7 +32,7 @@ test(T expected)
     assert(std::numeric_limits<const volatile T>::is_bounded);
 }
 
-int main()
+int main(int, char**)
 {
     test<bool>(true);
     test<char>(CHAR_MAX);
@@ -61,4 +61,6 @@ int main()
     test<float>(FLT_MAX);
     test<double>(DBL_MAX);
     test<long double>(LDBL_MAX);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/max_digits10.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/max_digits10.pass.cpp
index 4b87148752776e4fee0959b4131485d6009f54b6..3cf7d50969587265be3dc788298a62101ef1eea8 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/max_digits10.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/max_digits10.pass.cpp
@@ -25,7 +25,7 @@ test()
     static_assert(std::numeric_limits<const volatile T>::max_digits10 == expected, "max_digits10 test 4");
 }
 
-int main()
+int main(int, char**)
 {
     test<bool, 0>();
     test<char, 0>();
@@ -54,4 +54,6 @@ int main()
     test<float, 2+(FLT_MANT_DIG * 30103)/100000>();
     test<double, 2+(DBL_MANT_DIG * 30103)/100000>();
     test<long double, 2+(LDBL_MANT_DIG * 30103)/100000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/max_exponent.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/max_exponent.pass.cpp
index 7ce1ac9d7440d385c3b879596ed90d4a8e28dcfa..325ad797977c36d3ab8fbf1400647897f4116d97 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/max_exponent.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/max_exponent.pass.cpp
@@ -25,7 +25,7 @@ test()
     static_assert(std::numeric_limits<const volatile T>::max_exponent == expected, "max_exponent test 4");
 }
 
-int main()
+int main(int, char**)
 {
     test<bool, 0>();
     test<char, 0>();
@@ -54,4 +54,6 @@ int main()
     test<float, FLT_MAX_EXP>();
     test<double, DBL_MAX_EXP>();
     test<long double, LDBL_MAX_EXP>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/max_exponent10.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/max_exponent10.pass.cpp
index e2bbdde1096f82c2618374d38efc1bc2e50b34b1..e1a4ffe29beca9a7464c3da70d8c5010914c624f 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/max_exponent10.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/max_exponent10.pass.cpp
@@ -25,7 +25,7 @@ test()
     static_assert(std::numeric_limits<const volatile T>::max_exponent10 == expected, "max_exponent10 test 4");
 }
 
-int main()
+int main(int, char**)
 {
     test<bool, 0>();
     test<char, 0>();
@@ -54,4 +54,6 @@ int main()
     test<float, FLT_MAX_10_EXP>();
     test<double, DBL_MAX_10_EXP>();
     test<long double, LDBL_MAX_10_EXP>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/min.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/min.pass.cpp
index 66ddaa474e94c1612553f9b71222f7b66a6a36a5..0d2cb3c1bc3577aee2ee37289a6c5f87f848d450 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/min.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/min.pass.cpp
@@ -32,7 +32,7 @@ test(T expected)
     assert(std::numeric_limits<const volatile T>::is_bounded || !std::numeric_limits<const volatile T>::is_signed);
 }
 
-int main()
+int main(int, char**)
 {
     test<bool>(false);
     test<char>(CHAR_MIN);
@@ -61,4 +61,6 @@ int main()
     test<float>(FLT_MIN);
     test<double>(DBL_MIN);
     test<long double>(LDBL_MIN);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/min_exponent.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/min_exponent.pass.cpp
index 8fb4f09f6a74141ee97f7aa25626a8aecfc7ccbf..5708d8a20f59b8e42f58bc870940375a76c24b8c 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/min_exponent.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/min_exponent.pass.cpp
@@ -25,7 +25,7 @@ test()
     static_assert(std::numeric_limits<const volatile T>::min_exponent == expected, "min_exponent test 4");
 }
 
-int main()
+int main(int, char**)
 {
     test<bool, 0>();
     test<char, 0>();
@@ -54,4 +54,6 @@ int main()
     test<float, FLT_MIN_EXP>();
     test<double, DBL_MIN_EXP>();
     test<long double, LDBL_MIN_EXP>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/min_exponent10.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/min_exponent10.pass.cpp
index 812dd53bbe0f0b952aad8913bcb4774c1dd13903..f598d42fa8e64c15cd2488fe11dfa3b3ff2a9740 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/min_exponent10.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/min_exponent10.pass.cpp
@@ -25,7 +25,7 @@ test()
     static_assert(std::numeric_limits<const volatile T>::min_exponent10 == expected, "min_exponent10 test 4");
 }
 
-int main()
+int main(int, char**)
 {
     test<bool, 0>();
     test<char, 0>();
@@ -54,4 +54,6 @@ int main()
     test<float, FLT_MIN_10_EXP>();
     test<double, DBL_MIN_10_EXP>();
     test<long double, LDBL_MIN_10_EXP>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/quiet_NaN.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/quiet_NaN.pass.cpp
index 852cf86a13a71dad7451ff78be9ac9c23bcc4b40..f4ea61f23dc64c73ab97d4f42b2a5d064ac0fb8f 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/quiet_NaN.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/quiet_NaN.pass.cpp
@@ -45,7 +45,7 @@ test()
     test_imp<T>(std::is_floating_point<T>());
 }
 
-int main()
+int main(int, char**)
 {
     test<bool>();
     test<char>();
@@ -74,4 +74,6 @@ int main()
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/radix.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/radix.pass.cpp
index 8c9e48a2d71e68b467ab4742f134dba7e6621ecb..8f13768b0bdb4edaf576812b15a7d531590ccb6d 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/radix.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/radix.pass.cpp
@@ -25,7 +25,7 @@ test()
     static_assert(std::numeric_limits<const volatile T>::radix == expected, "radix test 4");
 }
 
-int main()
+int main(int, char**)
 {
     test<bool, 2>();
     test<char, 2>();
@@ -54,4 +54,6 @@ int main()
     test<float, FLT_RADIX>();
     test<double, FLT_RADIX>();
     test<long double, FLT_RADIX>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/round_error.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/round_error.pass.cpp
index f2d962df4b6fdfceecd037dbd008a7b033a1cd4b..ddc4490db0beb3f8538d168880cc3f6b96556b98 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/round_error.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/round_error.pass.cpp
@@ -26,7 +26,7 @@ test(T expected)
     assert(std::numeric_limits<const volatile T>::round_error() == expected);
 }
 
-int main()
+int main(int, char**)
 {
     test<bool>(false);
     test<char>(0);
@@ -55,4 +55,6 @@ int main()
     test<float>(0.5);
     test<double>(0.5);
     test<long double>(0.5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/round_style.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/round_style.pass.cpp
index 43e962961a624dec4267ba7c75c16ba8df441c31..81d4ce6ebcf1d4d88e3eea219ad4c74ba0e14a4e 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/round_style.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/round_style.pass.cpp
@@ -24,7 +24,7 @@ test()
     static_assert(std::numeric_limits<const volatile T>::round_style == expected, "round_style test 4");
 }
 
-int main()
+int main(int, char**)
 {
     test<bool, std::round_toward_zero>();
     test<char, std::round_toward_zero>();
@@ -53,4 +53,6 @@ int main()
     test<float, std::round_to_nearest>();
     test<double, std::round_to_nearest>();
     test<long double, std::round_to_nearest>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/signaling_NaN.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/signaling_NaN.pass.cpp
index 312f69714982dd3b45aaef58203b6e9062f12885..701386710955b608eba95a6dc67c55625ebc9e06 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/signaling_NaN.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/signaling_NaN.pass.cpp
@@ -45,7 +45,7 @@ test()
     test_imp<T>(std::is_floating_point<T>());
 }
 
-int main()
+int main(int, char**)
 {
     test<bool>();
     test<char>();
@@ -74,4 +74,6 @@ int main()
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/tinyness_before.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/tinyness_before.pass.cpp
index 3e0ad694b442a5142de263b38c16b48889ba4bd3..c150e5f23d063f91a22952aef8c3b9d5ef8021cc 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/tinyness_before.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/tinyness_before.pass.cpp
@@ -24,7 +24,7 @@ test()
     static_assert(std::numeric_limits<const volatile T>::tinyness_before == expected, "tinyness_before test 4");
 }
 
-int main()
+int main(int, char**)
 {
     test<bool, false>();
     test<char, false>();
@@ -53,4 +53,6 @@ int main()
     test<float, false>();
     test<double, false>();
     test<long double, false>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/traps.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/traps.pass.cpp
index e71432b18a180c6f6279fd8411e759cc1c8154b0..e7ea388192ded2a08a3318a9f18931f9ed2b143e 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/traps.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits.members/traps.pass.cpp
@@ -31,7 +31,7 @@ test()
     static_assert(std::numeric_limits<const volatile T>::traps == expected, "traps test 4");
 }
 
-int main()
+int main(int, char**)
 {
     test<bool, false>();
     test<char, integral_types_trap>();
@@ -60,4 +60,6 @@ int main()
     test<float, false>();
     test<double, false>();
     test<long double, false>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.limits/default.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.limits/default.pass.cpp
index 3c7cefd55cfd0611cdd8a7d194727177de516636..6e258c13a7888e8011814db71cb81b3786c46ea7 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.limits/default.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.limits/default.pass.cpp
@@ -22,7 +22,7 @@ struct A
 
 bool operator == (const A& x, const A& y) {return x.data_ == y.data_;}
 
-int main()
+int main(int, char**)
 {
     static_assert(std::numeric_limits<A>::is_specialized == false,
                  "std::numeric_limits<A>::is_specialized == false");
@@ -79,4 +79,6 @@ int main()
                  "std::numeric_limits<A>::tinyness_before == false");
     static_assert(std::numeric_limits<A>::round_style == std::round_toward_zero,
                  "std::numeric_limits<A>::round_style == std::round_toward_zero");
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/numeric.special/nothing_to_do.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/numeric.special/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/language.support/support.limits/limits/numeric.special/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/numeric.special/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/limits/round.style/check_values.pass.cpp b/libcxx/test/std/language.support/support.limits/limits/round.style/check_values.pass.cpp
index c6a01bf66fbcfaedafc9b960016997826a3d8a31..b1a4e4450a1ee84e7e0a4fd853c595ae99df7179 100644
--- a/libcxx/test/std/language.support/support.limits/limits/round.style/check_values.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/limits/round.style/check_values.pass.cpp
@@ -18,7 +18,7 @@ struct two {one _[2];};
 one test(std::float_denorm_style);
 two test(int);
 
-int main()
+int main(int, char**)
 {
     static_assert(std::denorm_indeterminate == -1,
                  "std::denorm_indeterminate == -1");
@@ -30,4 +30,6 @@ int main()
                  "sizeof(test(std::denorm_present)) == 1");
     static_assert(sizeof(test(1)) == 2,
                  "sizeof(test(1)) == 2");
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/nothing_to_do.pass.cpp b/libcxx/test/std/language.support/support.limits/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/language.support/support.limits/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/algorithm.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/algorithm.version.pass.cpp
index 57234ad4362cd8c420c5da006bcf4867c1ac6a15..5458e9194297db944491bd929d708ec4c1892e4b 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/algorithm.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/algorithm.version.pass.cpp
@@ -188,4 +188,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/any.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/any.version.pass.cpp
index 9bbaca7aa159729d9c9e8f8887ca1541460303d6..f5255c0e26a6db4ac900110e3b910f4dd682b718 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/any.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/any.version.pass.cpp
@@ -52,4 +52,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/array.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/array.version.pass.cpp
index 85bda432290aed2b15eab35be5dc4ba727c832be..d590f98042d523d43d1ad2960dde207d659a8128 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/array.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/array.version.pass.cpp
@@ -101,4 +101,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/atomic.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/atomic.version.pass.cpp
index 3fb2c7ed14774815b29d605a47814e3d52f944c7..d8f6f548cd23fb0410c485949728bc274f95a240 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/atomic.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/atomic.version.pass.cpp
@@ -118,4 +118,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/bit.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/bit.version.pass.cpp
index 6c26e06a0b03b22ed2a76a5829acc1861611fa02..3e42d06fbe81b9e3f97cc564632ebbd3ba78c8a8 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/bit.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/bit.version.pass.cpp
@@ -55,4 +55,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/charconv.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/charconv.pass.cpp
index 045dcb8ac38d83936d5526876c4f48d5438f18d0..2afe2e26ba55344d765fa2fc44e5965ab8eb2cde 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/charconv.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/charconv.pass.cpp
@@ -17,7 +17,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 //  ensure that the macros that are supposed to be defined in <utility> are defined.
 
@@ -28,4 +28,6 @@ int main()
 # error "__cpp_lib_fooby has an invalid value"
 #endif
 */
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/chrono.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/chrono.version.pass.cpp
index 9e434c5c2537da675e25317cf5b36b8fef95b14f..88da2dcca6d7863dc1b9f347c9efaf609246acc8 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/chrono.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/chrono.version.pass.cpp
@@ -78,4 +78,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/cmath.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/cmath.version.pass.cpp
index bcc2053585a0eaf067963756f379da77eeaba478..d81218e66ab9f6fafed0b71e8a43239e64967193 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/cmath.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/cmath.version.pass.cpp
@@ -87,4 +87,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/compare.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/compare.version.pass.cpp
index 2864c9f4eb0cea56880d3bdb77c86273d6fc79ad..7f1836fba00e67e2a3b6e017aaadc9aeb493a60d 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/compare.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/compare.version.pass.cpp
@@ -55,4 +55,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/complex.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/complex.version.pass.cpp
index c6a9b16481f036f2e654b143da6c9c7b2dae4540..bcff0bbe1856bce0c18b10b89e288c3e735638ed 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/complex.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/complex.version.pass.cpp
@@ -55,4 +55,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/concepts.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/concepts.version.pass.cpp
index 9d9b9bca3fe8110e8534c03dc39998d8452906e7..16febf8d3e24a16022a78f75a2cc87fa02d18365 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/concepts.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/concepts.version.pass.cpp
@@ -19,7 +19,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 //  ensure that the macros that are supposed to be defined in <concepts> are defined.
 
@@ -30,4 +30,6 @@ int main()
 # error "__cpp_lib_fooby has an invalid value"
 #endif
 */
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/cstddef.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/cstddef.version.pass.cpp
index 82a0932d0dc90b8b4243fe66d3baf1df366ce8a9..b18ea07ea0cc60f5fa9ec8ecd49fa4620150b21d 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/cstddef.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/cstddef.version.pass.cpp
@@ -52,4 +52,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/deque.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/deque.version.pass.cpp
index 53a1b33450bd1ba9924a4d82c5573cc744af3883..9d07dcdd24661eac80e17fcab62d1a7246e2f19f 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/deque.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/deque.version.pass.cpp
@@ -95,4 +95,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/exception.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/exception.version.pass.cpp
index c27bdc6b06342bf6dd3c4aa4b09955008ff42092..1ecebb48f0f544d3af50a4e1343dfe1ab9a29a2b 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/exception.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/exception.version.pass.cpp
@@ -52,4 +52,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/execution.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/execution.version.pass.cpp
index 476a31ef93f2ec8232369572572b8a7d1a547b79..b05f41bb1731c9350d8fef42c9be2a244d20947c 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/execution.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/execution.version.pass.cpp
@@ -19,7 +19,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 //  ensure that the macros that are supposed to be defined in <execution> are defined.
 
@@ -30,4 +30,6 @@ int main()
 # error "__cpp_lib_fooby has an invalid value"
 #endif
 */
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/filesystem.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/filesystem.version.pass.cpp
index 6638cdee90c88af4b82170557b8131f73faf759d..d1c09fc7ee4857eb40352a6eb9c123f2d3be6879 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/filesystem.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/filesystem.version.pass.cpp
@@ -78,4 +78,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/forward_list.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/forward_list.version.pass.cpp
index 102cd29ea568f5d559a554258d56fe09be26a228..7ecad6d3e3408fcef79b99eb6f92a7985b65deb3 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/forward_list.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/forward_list.version.pass.cpp
@@ -144,4 +144,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/functional.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/functional.version.pass.cpp
index e11464231193d5602aa6ab1bb19e0dcd0ff5619c..a29a1d708a3043477be28730d4c7f09311d26a25 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/functional.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/functional.version.pass.cpp
@@ -241,4 +241,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/iomanip.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/iomanip.version.pass.cpp
index bd2ea2417a28e5009819a2dfe462a72faa912275..23378e0e2e3c4f289b981658eeaf31e5def9a1ac 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/iomanip.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/iomanip.version.pass.cpp
@@ -55,4 +55,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/istream.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/istream.version.pass.cpp
index 9194ff855281f70f97257e8eb80d0c67bc66226f..3d8fb7a4cf9cb4881026664a44b7fd374c95fed6 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/istream.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/istream.version.pass.cpp
@@ -55,4 +55,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/iterator.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/iterator.version.pass.cpp
index b1ad28206f77d6e89d9308b973d02a63f96efb7b..9c1719b53cfe670be415de2d8b85c6f30d236f5b 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/iterator.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/iterator.version.pass.cpp
@@ -179,4 +179,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/limits.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/limits.version.pass.cpp
index bb2005e327cacb2eb97cd84f03eacdd661e1f5c7..2d2f243e70411c49c3890914c249d8d71ec7ae24 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/limits.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/limits.version.pass.cpp
@@ -55,4 +55,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/list.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/list.version.pass.cpp
index c1159cf73a1f7b35232aae089bc53cc138d5c46b..b736d1f9a2161704fbe5c69f0b6c6610b3bf31c6 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/list.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/list.version.pass.cpp
@@ -144,4 +144,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/locale.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/locale.version.pass.cpp
index c5a5b543650dcd4d3f80d1f3e56894b1ef9f847f..eeea5390afd8cf48e24e04e2d657ebeea696e621 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/locale.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/locale.version.pass.cpp
@@ -55,4 +55,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/map.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/map.version.pass.cpp
index c1ecad7232172a0be27b274ec2ef016ab6baf8df..a41dd1b8e9862df55b663dcfae854c6f537729ad 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/map.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/map.version.pass.cpp
@@ -167,4 +167,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/memory.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/memory.version.pass.cpp
index 55e595fa9a80e3cce2978c61e42640ab6e7d2506..6c845d71febd7c17b6283e7aba339efc63a89f1f 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/memory.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/memory.version.pass.cpp
@@ -243,4 +243,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/memory_resource.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/memory_resource.version.pass.cpp
index cb182adc16a1fbce6ab04c9620ccfa0f6f9d4d92..d712a8bca8d1f727dccbeba202f33064934b2741 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/memory_resource.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/memory_resource.version.pass.cpp
@@ -19,7 +19,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 //  ensure that the macros that are supposed to be defined in <memory_resource> are defined.
 
@@ -30,4 +30,6 @@ int main()
 # error "__cpp_lib_fooby has an invalid value"
 #endif
 */
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/mutex.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/mutex.version.pass.cpp
index 4986a1f192db230415af109708ffc18e54929f0b..9dae806b8123118d857847567196c52482a91ff5 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/mutex.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/mutex.version.pass.cpp
@@ -52,4 +52,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/new.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/new.version.pass.cpp
index 95a717dfbd29dadc0f36b0af4f35dff81b1a3081..5f012cd55f6c2a831a67585049d68d4b12547f54 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/new.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/new.version.pass.cpp
@@ -101,4 +101,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/numeric.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/numeric.version.pass.cpp
index f44cbc2c75c29e22b809c4ce60b9559794ff77da..eb5eb557b7bb75890414123b52c0fc52a78e93d6 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/numeric.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/numeric.version.pass.cpp
@@ -87,4 +87,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/optional.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/optional.version.pass.cpp
index 59e698d769df4a791ce6b2b4722b25b80fd9234f..d88fbb0fee804a3b5cf34eb5c65ba7f956cc3666 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/optional.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/optional.version.pass.cpp
@@ -52,4 +52,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/ostream.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/ostream.version.pass.cpp
index 17be75c2e721fad40a8867b2661e4e24e19b7001..d3ba25867d0536f5341e2576b631a3d34bddb90e 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/ostream.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/ostream.version.pass.cpp
@@ -55,4 +55,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/regex.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/regex.version.pass.cpp
index 412e29c6c5491131398aa532e64a493d4ebd083d..66becadbbfb824d53b24d80d9eff1c0e52ce4570 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/regex.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/regex.version.pass.cpp
@@ -52,4 +52,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/scoped_allocator.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/scoped_allocator.version.pass.cpp
index d111f263c13d2a01c18e351c8faf90a69039d61d..2ea98256e1bd496f1f0a524cd865264c6778aa89 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/scoped_allocator.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/scoped_allocator.version.pass.cpp
@@ -52,4 +52,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/set.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/set.version.pass.cpp
index c886850ceba70d1da823d621415b44411c9decee..80cf9c0af3caaf459a9c6dd7e387e152327b5699 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/set.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/set.version.pass.cpp
@@ -144,4 +144,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/shared_mutex.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/shared_mutex.version.pass.cpp
index 12c58480bdfa8a2e1efbce501b4bbea0d16d3d50..7c92dfc085cea7bb1735c136a954e34876268a2d 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/shared_mutex.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/shared_mutex.version.pass.cpp
@@ -110,4 +110,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/string.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/string.version.pass.cpp
index 0f1c37b90e4fe7a0a5ffcea8b90aca5391991a5b..bdd517da0de6dbbd3161b0fb2453aabb32279d2e 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/string.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/string.version.pass.cpp
@@ -170,4 +170,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/string_view.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/string_view.version.pass.cpp
index adad6b084e35a788fdb61765bd338832ccd69845..816083e0d7f3362aee3a8d93971f070d83de2863 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/string_view.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/string_view.version.pass.cpp
@@ -104,4 +104,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/tuple.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/tuple.version.pass.cpp
index e2d9865324eb072b93febf12084f73931a37f921..5c1e6580c57d6b87e514f6ddcbb7a28bff34d66e 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/tuple.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/tuple.version.pass.cpp
@@ -153,4 +153,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/type_traits.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/type_traits.version.pass.cpp
index 59994b77956af1efcec7d3e2679353d771de145d..7e8b3de35f4c2e3dfb84d0c3c393cdbc503b7606 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/type_traits.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/type_traits.version.pass.cpp
@@ -393,4 +393,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/unordered_map.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/unordered_map.version.pass.cpp
index f6f4e6cecc225da725a5078445575bdf24eae27e..07eb1a9bc351af3eef64d998a08fb2e7b26ebfc6 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/unordered_map.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/unordered_map.version.pass.cpp
@@ -167,4 +167,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/unordered_set.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/unordered_set.version.pass.cpp
index 07a3c302adc81b7c9823a89b85bf6c4d53205c6a..845318a79a5e9b4a01c415c118ca07cc3fb4f665 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/unordered_set.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/unordered_set.version.pass.cpp
@@ -144,4 +144,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/utility.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/utility.version.pass.cpp
index 6b051d289d48cf1cfff3e8d219359a137afef8bf..1fd38627a715a9964b752e41bd4e62a740357b33 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/utility.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/utility.version.pass.cpp
@@ -191,4 +191,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/variant.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/variant.version.pass.cpp
index 23a15a67060ba9da7c60938b12f4f1d355edb2b5..7a17307460d81f5196789e791a32cbbf957e935e 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/variant.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/variant.version.pass.cpp
@@ -52,4 +52,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/vector.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/vector.version.pass.cpp
index c22921e775dbbae18686c35a88dd83867d7292e7..3ea2a0cf00b18dbde6286209ee5de6ab4bb3aaf8 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/vector.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/vector.version.pass.cpp
@@ -118,4 +118,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/version.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/version.version.pass.cpp
index aa409e1547a4e6df3aa1dd899a0b81e7e5e15ed2..b85d42d00ca789d5f39cbbcaee3f7e30c4e03c99 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/version.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/version.version.pass.cpp
@@ -2174,4 +2174,4 @@
 
 #endif // TEST_STD_VER > 17
 
-int main() {}
+int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/language.support/support.limits/version.pass.cpp b/libcxx/test/std/language.support/support.limits/version.pass.cpp
index b67df2892f08874f7828c22613d61e49f80ecf13..783af5c728b5a9689ae9d0665cdfdb8de5b37f8e 100644
--- a/libcxx/test/std/language.support/support.limits/version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/version.pass.cpp
@@ -11,6 +11,8 @@
 
 #include <version>
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.rtti/bad.cast/bad_cast.pass.cpp b/libcxx/test/std/language.support/support.rtti/bad.cast/bad_cast.pass.cpp
index 5f9dc962daff27be9f0045db9cc80bcabd216e11..23afd223cc40edb99dc1a9381b127c78b4f8a48b 100644
--- a/libcxx/test/std/language.support/support.rtti/bad.cast/bad_cast.pass.cpp
+++ b/libcxx/test/std/language.support/support.rtti/bad.cast/bad_cast.pass.cpp
@@ -12,7 +12,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::exception, std::bad_cast>::value),
                  "std::is_base_of<std::exception, std::bad_cast>::value");
@@ -23,4 +23,6 @@ int main()
     b2 = b;
     const char* w = b2.what();
     assert(w);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.rtti/bad.typeid/bad_typeid.pass.cpp b/libcxx/test/std/language.support/support.rtti/bad.typeid/bad_typeid.pass.cpp
index 90b6bc20a30499ff4bf96dd95b9b6f0435283e1f..94424bb03ad070f281777806d312b4a361eda1d1 100644
--- a/libcxx/test/std/language.support/support.rtti/bad.typeid/bad_typeid.pass.cpp
+++ b/libcxx/test/std/language.support/support.rtti/bad.typeid/bad_typeid.pass.cpp
@@ -12,7 +12,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::exception, std::bad_typeid>::value),
                  "std::is_base_of<std::exception, std::bad_typeid>::value");
@@ -23,4 +23,6 @@ int main()
     b2 = b;
     const char* w = b2.what();
     assert(w);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.rtti/type.info/type_info.pass.cpp b/libcxx/test/std/language.support/support.rtti/type.info/type_info.pass.cpp
index fec07526a2ed49263e333be00ac3aa34cc8e62b7..980bfeeccdcb6c0314b404f3b552337f8d4611b5 100644
--- a/libcxx/test/std/language.support/support.rtti/type.info/type_info.pass.cpp
+++ b/libcxx/test/std/language.support/support.rtti/type.info/type_info.pass.cpp
@@ -16,7 +16,7 @@
 bool test_constructor_explicit(std::type_info const&) { return false; }
 bool test_constructor_explicit(std::string const&) { return true; }
 
-int main()
+int main(int, char**)
 {
   {
     const std::type_info& t1 = typeid(int);
@@ -36,4 +36,6 @@ int main()
     // See: https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=216201
     assert(test_constructor_explicit("abc"));
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.rtti/type.info/type_info_hash.pass.cpp b/libcxx/test/std/language.support/support.rtti/type.info/type_info_hash.pass.cpp
index d519622b7b1a2ac21feca7dafa2b65a430fdf79b..c65f3bbf7900e5f986e8e36002234b2a0bf0ee28 100644
--- a/libcxx/test/std/language.support/support.rtti/type.info/type_info_hash.pass.cpp
+++ b/libcxx/test/std/language.support/support.rtti/type.info/type_info_hash.pass.cpp
@@ -12,11 +12,13 @@
 #include <cstring>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::type_info& t1 = typeid(int);
     const std::type_info& t2 = typeid(int);
     const std::type_info& t3 = typeid(short);
     assert(t1.hash_code() == t2.hash_code());
     assert(t1.hash_code() != t3.hash_code());
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.runtime/csetjmp.pass.cpp b/libcxx/test/std/language.support/support.runtime/csetjmp.pass.cpp
index dc68bf4a342bd97cc89b49c37ebc175d9cb3fe91..c1fa71b0e376ea65081c832b796604ec4c43e9ab 100644
--- a/libcxx/test/std/language.support/support.runtime/csetjmp.pass.cpp
+++ b/libcxx/test/std/language.support/support.runtime/csetjmp.pass.cpp
@@ -15,10 +15,12 @@
 #error setjmp not defined
 #endif
 
-int main()
+int main(int, char**)
 {
     std::jmp_buf jb;
     ((void)jb); // Prevent unused warning
     static_assert((std::is_same<decltype(std::longjmp(jb, 0)), void>::value),
                   "std::is_same<decltype(std::longjmp(jb, 0)), void>::value");
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.runtime/csignal.pass.cpp b/libcxx/test/std/language.support/support.runtime/csignal.pass.cpp
index b827236bb7f8bc2dc8fb080d7f81a87615534019..dcfb4f99f5f249e5962225b25091262c37283644 100644
--- a/libcxx/test/std/language.support/support.runtime/csignal.pass.cpp
+++ b/libcxx/test/std/language.support/support.runtime/csignal.pass.cpp
@@ -47,11 +47,13 @@
 #error SIGTERM not defined
 #endif
 
-int main()
+int main(int, char**)
 {
     std::sig_atomic_t sig = 0;
     ((void)sig);
     typedef void (*func)(int);
     static_assert((std::is_same<decltype(std::signal(0, (func)0)), func>::value), "");
     static_assert((std::is_same<decltype(std::raise(0)), int>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.runtime/cstdarg.pass.cpp b/libcxx/test/std/language.support/support.runtime/cstdarg.pass.cpp
index b3c919af05fb7cdefb43baea1cd34e59504bb488..8d7fd70b75aa8595e73cb5c73901ea081f1eadb8 100644
--- a/libcxx/test/std/language.support/support.runtime/cstdarg.pass.cpp
+++ b/libcxx/test/std/language.support/support.runtime/cstdarg.pass.cpp
@@ -30,8 +30,10 @@
 #error va_start not defined
 #endif
 
-int main()
+int main(int, char**)
 {
     std::va_list va;
     ((void)va);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.runtime/cstdbool.pass.cpp b/libcxx/test/std/language.support/support.runtime/cstdbool.pass.cpp
index 98a0e7e498959e655c001987fee93b2e58820911..461e77c99838e9171a29574106fc3f9f9aa2908d 100644
--- a/libcxx/test/std/language.support/support.runtime/cstdbool.pass.cpp
+++ b/libcxx/test/std/language.support/support.runtime/cstdbool.pass.cpp
@@ -26,6 +26,8 @@
 #error false should not be defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.runtime/cstdlib.pass.cpp b/libcxx/test/std/language.support/support.runtime/cstdlib.pass.cpp
index bc2cfcbb49df5331ab56a020851ead51b4398caf..d8b6636795d8fa13cf6a40b861054a810954596e 100644
--- a/libcxx/test/std/language.support/support.runtime/cstdlib.pass.cpp
+++ b/libcxx/test/std/language.support/support.runtime/cstdlib.pass.cpp
@@ -49,7 +49,7 @@ void test_div_struct() {
     ((void) obj);
 };
 
-int main()
+int main(int, char**)
 {
     std::size_t s = 0;
     ((void)s);
@@ -108,4 +108,6 @@ int main()
     static_assert((std::is_same<decltype(std::wctomb(pc,L' ')), int>::value), "");
     static_assert((std::is_same<decltype(std::mbstowcs(pw,"",0)), std::size_t>::value), "");
     static_assert((std::is_same<decltype(std::wcstombs(pc,pwc,0)), std::size_t>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.runtime/ctime.pass.cpp b/libcxx/test/std/language.support/support.runtime/ctime.pass.cpp
index 57fb0124515e1dec12d1daf0cd6529bea70ef279..a8c2dc7ff56759f2812adccfb53f38b698b52a70 100644
--- a/libcxx/test/std/language.support/support.runtime/ctime.pass.cpp
+++ b/libcxx/test/std/language.support/support.runtime/ctime.pass.cpp
@@ -26,7 +26,7 @@
 #endif
 #endif
 
-int main()
+int main(int, char**)
 {
     std::clock_t c = 0;
     std::size_t s = 0;
@@ -58,4 +58,6 @@ int main()
     ((void)c1); // Prevent unused warning
     ((void)c2); // Prevent unused warning
     static_assert((std::is_same<decltype(std::strftime(c1,s,c2,&tm)), std::size_t>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.start.term/quick_exit.pass.cpp b/libcxx/test/std/language.support/support.start.term/quick_exit.pass.cpp
index 5b7c36b08af9f38789c21bd525d4e8b2b80ece75..50d408aa0ba0f57fa618199a90d54300fec7ae55 100644
--- a/libcxx/test/std/language.support/support.start.term/quick_exit.pass.cpp
+++ b/libcxx/test/std/language.support/support.start.term/quick_exit.pass.cpp
@@ -13,10 +13,12 @@
 
 void f() {}
 
-int main()
+int main(int, char**)
 {
 #ifdef _LIBCPP_HAS_QUICK_EXIT
     std::at_quick_exit(f);
     std::quick_exit(0);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.start.term/quick_exit_check1.fail.cpp b/libcxx/test/std/language.support/support.start.term/quick_exit_check1.fail.cpp
index c1703f2bee6c2642c48b7298e2d4f3468f823f39..63c97f21025f65f967904030819b05b6e275bfac 100644
--- a/libcxx/test/std/language.support/support.start.term/quick_exit_check1.fail.cpp
+++ b/libcxx/test/std/language.support/support.start.term/quick_exit_check1.fail.cpp
@@ -15,11 +15,13 @@
 
 void f() {}
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_QUICK_EXIT
     std::at_quick_exit(f);
 #else
 #error
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.start.term/quick_exit_check2.fail.cpp b/libcxx/test/std/language.support/support.start.term/quick_exit_check2.fail.cpp
index acf10068b979469b81ae2ca99483409430dafc8a..28929b1aed346b1d2088e63c2cfcaba275165d27 100644
--- a/libcxx/test/std/language.support/support.start.term/quick_exit_check2.fail.cpp
+++ b/libcxx/test/std/language.support/support.start.term/quick_exit_check2.fail.cpp
@@ -14,11 +14,13 @@
 
 void f() {}
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_QUICK_EXIT
     std::quick_exit(0);
 #else
 #error
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.types/byte.pass.cpp b/libcxx/test/std/language.support/support.types/byte.pass.cpp
index a4a9e821908ea7025f6d53ae0f62ae1b072bf88f..842dc38d353810304b3b0d0f58db0ef74596f505 100644
--- a/libcxx/test/std/language.support/support.types/byte.pass.cpp
+++ b/libcxx/test/std/language.support/support.types/byte.pass.cpp
@@ -30,4 +30,6 @@ static_assert(!std::is_same<std::byte, unsigned char>::value, "" );
 // The standard doesn't outright say this, but it's pretty clear that it has to be true.
 static_assert(sizeof(std::byte) == 1, "" );
 
-int main () {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/std/language.support/support.types/byteops/and.assign.pass.cpp b/libcxx/test/std/language.support/support.types/byteops/and.assign.pass.cpp
index e4875d38f33d94f041b6b0c543764987cbb3fe35..9ecdb5f6c0d89d0f3ea99e384d073314bd7c05b2 100644
--- a/libcxx/test/std/language.support/support.types/byteops/and.assign.pass.cpp
+++ b/libcxx/test/std/language.support/support.types/byteops/and.assign.pass.cpp
@@ -20,7 +20,7 @@ constexpr std::byte test(std::byte b1, std::byte b2) {
     }
 
 
-int main () {
+int main(int, char**) {
     std::byte b;  // not constexpr, just used in noexcept check
     constexpr std::byte b1{static_cast<std::byte>(1)};
     constexpr std::byte b8{static_cast<std::byte>(8)};
@@ -35,4 +35,6 @@ int main () {
     static_assert(std::to_integer<int>(test(b8, b1)) == 0, "");
     static_assert(std::to_integer<int>(test(b9, b1)) == 1, "");
     static_assert(std::to_integer<int>(test(b9, b8)) == 8, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.types/byteops/and.pass.cpp b/libcxx/test/std/language.support/support.types/byteops/and.pass.cpp
index 312e679cd2c95afca31a64b95eda6d1f57c8e734..d1dbc75f70cafb8b5e6f5eebe72c058533651022 100644
--- a/libcxx/test/std/language.support/support.types/byteops/and.pass.cpp
+++ b/libcxx/test/std/language.support/support.types/byteops/and.pass.cpp
@@ -13,7 +13,7 @@
 
 // constexpr byte operator&(byte l, byte r) noexcept;
 
-int main () {
+int main(int, char**) {
     constexpr std::byte b1{static_cast<std::byte>(1)};
     constexpr std::byte b8{static_cast<std::byte>(8)};
     constexpr std::byte b9{static_cast<std::byte>(9)};
@@ -27,4 +27,6 @@ int main () {
     static_assert(std::to_integer<int>(b8 & b1) ==  0, "");
     static_assert(std::to_integer<int>(b9 & b1) ==  1, "");
     static_assert(std::to_integer<int>(b9 & b8) ==  8, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.types/byteops/enum_direct_init.pass.cpp b/libcxx/test/std/language.support/support.types/byteops/enum_direct_init.pass.cpp
index 99660b6b180aba38cf4fa3f3d07f7713d20b505e..5111667cee0da5c9700a17fbf440f558d6903826 100644
--- a/libcxx/test/std/language.support/support.types/byteops/enum_direct_init.pass.cpp
+++ b/libcxx/test/std/language.support/support.types/byteops/enum_direct_init.pass.cpp
@@ -14,7 +14,9 @@
 // XFAIL: clang-3.5, clang-3.6, clang-3.7, clang-3.8
 // XFAIL: apple-clang-6, apple-clang-7, apple-clang-8.0
 
-int main () {
+int main(int, char**) {
   constexpr std::byte b{42};
   static_assert(std::to_integer<int>(b) == 42, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.types/byteops/lshift.assign.fail.cpp b/libcxx/test/std/language.support/support.types/byteops/lshift.assign.fail.cpp
index 413b62b1f427f1280de1bde6f350b4977fb5ea24..8f2134b20729c04b80924cc25dc33ceea20abdfe 100644
--- a/libcxx/test/std/language.support/support.types/byteops/lshift.assign.fail.cpp
+++ b/libcxx/test/std/language.support/support.types/byteops/lshift.assign.fail.cpp
@@ -25,6 +25,8 @@ constexpr std::byte test(std::byte b) {
     }
 
 
-int main () {
+int main(int, char**) {
     constexpr std::byte b1 = test(std::byte{1});
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.types/byteops/lshift.assign.pass.cpp b/libcxx/test/std/language.support/support.types/byteops/lshift.assign.pass.cpp
index 9fe86883f4ec6f152c6692fda7863aa03e819936..3647f5c64fc7b4945a241485edfbe78f4b1a2f2a 100644
--- a/libcxx/test/std/language.support/support.types/byteops/lshift.assign.pass.cpp
+++ b/libcxx/test/std/language.support/support.types/byteops/lshift.assign.pass.cpp
@@ -22,7 +22,7 @@ constexpr std::byte test(std::byte b) {
     }
 
 
-int main () {
+int main(int, char**) {
     std::byte b;  // not constexpr, just used in noexcept check
     constexpr std::byte b2{static_cast<std::byte>(2)};
     constexpr std::byte b3{static_cast<std::byte>(3)};
@@ -32,4 +32,6 @@ int main () {
     static_assert(std::to_integer<int>(test(b2)) ==  8, "" );
     static_assert(std::to_integer<int>(test(b3)) == 12, "" );
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.types/byteops/lshift.fail.cpp b/libcxx/test/std/language.support/support.types/byteops/lshift.fail.cpp
index 6d889ed23e02f27dddd3f30cfd6eb2ea9f0b58be..83ce5b81e3f79e23ddd5d1470477d10e679314b4 100644
--- a/libcxx/test/std/language.support/support.types/byteops/lshift.fail.cpp
+++ b/libcxx/test/std/language.support/support.types/byteops/lshift.fail.cpp
@@ -16,7 +16,9 @@
 // These functions shall not participate in overload resolution unless
 //   is_integral_v<IntegerType> is true.
 
-int main () {
+int main(int, char**) {
     constexpr std::byte b1{static_cast<std::byte>(1)};
     constexpr std::byte b2 = b1 << 2.0f;
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.types/byteops/lshift.pass.cpp b/libcxx/test/std/language.support/support.types/byteops/lshift.pass.cpp
index 73cc66373c66faa810ba14e4dfe88f43bc1f7a49..855eebdf4ae00e908cbde3f5a6e1658f78326de7 100644
--- a/libcxx/test/std/language.support/support.types/byteops/lshift.pass.cpp
+++ b/libcxx/test/std/language.support/support.types/byteops/lshift.pass.cpp
@@ -16,7 +16,7 @@
 // These functions shall not participate in overload resolution unless
 //   is_integral_v<IntegerType> is true.
 
-int main () {
+int main(int, char**) {
     constexpr std::byte b1{static_cast<std::byte>(1)};
     constexpr std::byte b3{static_cast<std::byte>(3)};
 
@@ -26,4 +26,6 @@ int main () {
     static_assert(std::to_integer<int>(b1 << 2) ==   4, "");
     static_assert(std::to_integer<int>(b3 << 4) ==  48, "");
     static_assert(std::to_integer<int>(b3 << 6) == 192, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.types/byteops/not.pass.cpp b/libcxx/test/std/language.support/support.types/byteops/not.pass.cpp
index cb94e3659b6f346b5d5ea15ceb4682fd6d79f877..d6252aa356e0994db57d5a5c6a5224612aa44796 100644
--- a/libcxx/test/std/language.support/support.types/byteops/not.pass.cpp
+++ b/libcxx/test/std/language.support/support.types/byteops/not.pass.cpp
@@ -13,7 +13,7 @@
 
 // constexpr byte operator~(byte b) noexcept;
 
-int main () {
+int main(int, char**) {
     constexpr std::byte b1{static_cast<std::byte>(1)};
     constexpr std::byte b2{static_cast<std::byte>(2)};
     constexpr std::byte b8{static_cast<std::byte>(8)};
@@ -23,4 +23,6 @@ int main () {
     static_assert(std::to_integer<int>(~b1) == 254, "");
     static_assert(std::to_integer<int>(~b2) == 253, "");
     static_assert(std::to_integer<int>(~b8) == 247, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.types/byteops/or.assign.pass.cpp b/libcxx/test/std/language.support/support.types/byteops/or.assign.pass.cpp
index cad3acef327d79e04347e89864e74b676c60df11..1216b852b82b318017d4ccac626dadc85daa3f95 100644
--- a/libcxx/test/std/language.support/support.types/byteops/or.assign.pass.cpp
+++ b/libcxx/test/std/language.support/support.types/byteops/or.assign.pass.cpp
@@ -20,7 +20,7 @@ constexpr std::byte test(std::byte b1, std::byte b2) {
     }
 
 
-int main () {
+int main(int, char**) {
     std::byte b;  // not constexpr, just used in noexcept check
     constexpr std::byte b1{static_cast<std::byte>(1)};
     constexpr std::byte b2{static_cast<std::byte>(2)};
@@ -36,4 +36,6 @@ int main () {
     static_assert(std::to_integer<int>(test(b8, b1)) ==  9, "");
     static_assert(std::to_integer<int>(test(b8, b2)) == 10, "");
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.types/byteops/or.pass.cpp b/libcxx/test/std/language.support/support.types/byteops/or.pass.cpp
index 4b778398d932652a7c9e11dfdbcb2ed767e4c779..69b5bfaacb2b58a6052855ea7723c129ec355d20 100644
--- a/libcxx/test/std/language.support/support.types/byteops/or.pass.cpp
+++ b/libcxx/test/std/language.support/support.types/byteops/or.pass.cpp
@@ -13,7 +13,7 @@
 
 // constexpr byte operator|(byte l, byte r) noexcept;
 
-int main () {
+int main(int, char**) {
     constexpr std::byte b1{static_cast<std::byte>(1)};
     constexpr std::byte b2{static_cast<std::byte>(2)};
     constexpr std::byte b8{static_cast<std::byte>(8)};
@@ -27,4 +27,6 @@ int main () {
     static_assert(std::to_integer<int>(b2 | b1) ==  3, "");
     static_assert(std::to_integer<int>(b8 | b1) ==  9, "");
     static_assert(std::to_integer<int>(b8 | b2) == 10, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.types/byteops/rshift.assign.fail.cpp b/libcxx/test/std/language.support/support.types/byteops/rshift.assign.fail.cpp
index dcd6567341e6d705fd4319e8ce58c8eaf0a35350..714f5cd8b13dd8648d1616067445f85589d60443 100644
--- a/libcxx/test/std/language.support/support.types/byteops/rshift.assign.fail.cpp
+++ b/libcxx/test/std/language.support/support.types/byteops/rshift.assign.fail.cpp
@@ -25,6 +25,8 @@ constexpr std::byte test(std::byte b) {
     }
 
 
-int main () {
+int main(int, char**) {
     constexpr std::byte b1 = test(std::byte{1});
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.types/byteops/rshift.assign.pass.cpp b/libcxx/test/std/language.support/support.types/byteops/rshift.assign.pass.cpp
index bbb921240bb130b9c302b58a191db6b9e4e0f0b8..b1ca9d85135747ae4dddff5ade5f45681b7c14b1 100644
--- a/libcxx/test/std/language.support/support.types/byteops/rshift.assign.pass.cpp
+++ b/libcxx/test/std/language.support/support.types/byteops/rshift.assign.pass.cpp
@@ -22,7 +22,7 @@ constexpr std::byte test(std::byte b) {
     }
 
 
-int main () {
+int main(int, char**) {
     std::byte b;  // not constexpr, just used in noexcept check
     constexpr std::byte b16{static_cast<std::byte>(16)};
     constexpr std::byte b192{static_cast<std::byte>(192)};
@@ -31,4 +31,6 @@ int main () {
 
     static_assert(std::to_integer<int>(test(b16))  ==  4, "" );
     static_assert(std::to_integer<int>(test(b192)) == 48, "" );
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.types/byteops/rshift.fail.cpp b/libcxx/test/std/language.support/support.types/byteops/rshift.fail.cpp
index 1dc5f83cfca21359c1d616f137b55232e0c029e5..6af06f4fc68af66bb8bbb135620bfa72cb4f9f18 100644
--- a/libcxx/test/std/language.support/support.types/byteops/rshift.fail.cpp
+++ b/libcxx/test/std/language.support/support.types/byteops/rshift.fail.cpp
@@ -16,7 +16,9 @@
 // These functions shall not participate in overload resolution unless
 //   is_integral_v<IntegerType> is true.
 
-int main () {
+int main(int, char**) {
     constexpr std::byte b1{static_cast<std::byte>(1)};
     constexpr std::byte b2 = b1 >> 2.0f;
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.types/byteops/rshift.pass.cpp b/libcxx/test/std/language.support/support.types/byteops/rshift.pass.cpp
index 2ca3c6c20b26ad13ea9f9c66768897ef162b6e64..64db7556cd51ab399a5dbc68e2e6acc73ddb7cbe 100644
--- a/libcxx/test/std/language.support/support.types/byteops/rshift.pass.cpp
+++ b/libcxx/test/std/language.support/support.types/byteops/rshift.pass.cpp
@@ -22,7 +22,7 @@ constexpr std::byte test(std::byte b) {
     }
 
 
-int main () {
+int main(int, char**) {
     constexpr std::byte b100{static_cast<std::byte>(100)};
     constexpr std::byte b115{static_cast<std::byte>(115)};
 
@@ -33,4 +33,6 @@ int main () {
     static_assert(std::to_integer<int>(b115 >> 3) ==  14, "");
     static_assert(std::to_integer<int>(b115 >> 6) ==   1, "");
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.types/byteops/to_integer.fail.cpp b/libcxx/test/std/language.support/support.types/byteops/to_integer.fail.cpp
index ea3836b16a4eaf89624c50dc4b6245ca5ac3d9df..64996358c9c6c15fa5e949dc958e3ebf1b245382 100644
--- a/libcxx/test/std/language.support/support.types/byteops/to_integer.fail.cpp
+++ b/libcxx/test/std/language.support/support.types/byteops/to_integer.fail.cpp
@@ -16,7 +16,9 @@
 // This function shall not participate in overload resolution unless
 //   is_integral_v<IntegerType> is true.
 
-int main () {
+int main(int, char**) {
     constexpr std::byte b1{static_cast<std::byte>(1)};
     auto f = std::to_integer<float>(b1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.types/byteops/to_integer.pass.cpp b/libcxx/test/std/language.support/support.types/byteops/to_integer.pass.cpp
index cdae92ac4c91315d4aae984765b7b63247f10178..657d17d9c4516cb3f3678f3a94e5cdf2df6e9f99 100644
--- a/libcxx/test/std/language.support/support.types/byteops/to_integer.pass.cpp
+++ b/libcxx/test/std/language.support/support.types/byteops/to_integer.pass.cpp
@@ -16,7 +16,7 @@
 // This function shall not participate in overload resolution unless
 //   is_integral_v<IntegerType> is true.
 
-int main () {
+int main(int, char**) {
     constexpr std::byte b1{static_cast<std::byte>(1)};
     constexpr std::byte b3{static_cast<std::byte>(3)};
 
@@ -27,4 +27,6 @@ int main () {
 
     static_assert(std::to_integer<int>(b1) == 1, "");
     static_assert(std::to_integer<int>(b3) == 3, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.types/byteops/xor.assign.pass.cpp b/libcxx/test/std/language.support/support.types/byteops/xor.assign.pass.cpp
index 8caeec7dcc52124ababb061704c4af3ada1492a7..c82a6fd191b1d9b97a14d3f4b784ebb0637656d8 100644
--- a/libcxx/test/std/language.support/support.types/byteops/xor.assign.pass.cpp
+++ b/libcxx/test/std/language.support/support.types/byteops/xor.assign.pass.cpp
@@ -20,7 +20,7 @@ constexpr std::byte test(std::byte b1, std::byte b2) {
     }
 
 
-int main () {
+int main(int, char**) {
     std::byte b;  // not constexpr, just used in noexcept check
     constexpr std::byte b1{static_cast<std::byte>(1)};
     constexpr std::byte b8{static_cast<std::byte>(8)};
@@ -35,4 +35,6 @@ int main () {
     static_assert(std::to_integer<int>(test(b8, b1)) == 9, "");
     static_assert(std::to_integer<int>(test(b9, b1)) == 8, "");
     static_assert(std::to_integer<int>(test(b9, b8)) == 1, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.types/byteops/xor.pass.cpp b/libcxx/test/std/language.support/support.types/byteops/xor.pass.cpp
index 1dbf07f36c0ecc8ec290280e9a386b0b5cd2be9d..150f455b1db403e0f0ffd7574fbf057c41515ac4 100644
--- a/libcxx/test/std/language.support/support.types/byteops/xor.pass.cpp
+++ b/libcxx/test/std/language.support/support.types/byteops/xor.pass.cpp
@@ -13,7 +13,7 @@
 
 // constexpr byte operator^(byte l, byte r) noexcept;
 
-int main () {
+int main(int, char**) {
     constexpr std::byte b1{static_cast<std::byte>(1)};
     constexpr std::byte b8{static_cast<std::byte>(8)};
     constexpr std::byte b9{static_cast<std::byte>(9)};
@@ -27,4 +27,6 @@ int main () {
     static_assert(std::to_integer<int>(b8 ^ b1) == 9, "");
     static_assert(std::to_integer<int>(b9 ^ b1) == 8, "");
     static_assert(std::to_integer<int>(b9 ^ b8) == 1, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.types/max_align_t.pass.cpp b/libcxx/test/std/language.support/support.types/max_align_t.pass.cpp
index 50c4f5ef5a6dddd59dc84042855cd78f6c3ea52d..a49f598dff7b8f88bc8a0bdbef08b7d15d88f9b5 100644
--- a/libcxx/test/std/language.support/support.types/max_align_t.pass.cpp
+++ b/libcxx/test/std/language.support/support.types/max_align_t.pass.cpp
@@ -15,7 +15,7 @@
 #include <stdio.h>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 
 #if TEST_STD_VER > 17
@@ -40,4 +40,6 @@ int main()
                   std::alignment_of<void*>::value,
                   "std::alignment_of<std::max_align_t>::value >= "
                   "std::alignment_of<void*>::value");
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.types/null.pass.cpp b/libcxx/test/std/language.support/support.types/null.pass.cpp
index ce8530a00d47a64b5e2426dc398a847c4706324a..66ecdbc147c9361312e3db6b4e09fb52ee2f1c2c 100644
--- a/libcxx/test/std/language.support/support.types/null.pass.cpp
+++ b/libcxx/test/std/language.support/support.types/null.pass.cpp
@@ -12,6 +12,8 @@
 #error NULL not defined
 #endif
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.types/nullptr_t.pass.cpp b/libcxx/test/std/language.support/support.types/nullptr_t.pass.cpp
index 01a674a0a22db732bf62b479ef0dcf0541429953..14ab3c65d02451ccdb7b26e7cbbd154ed353b2d9 100644
--- a/libcxx/test/std/language.support/support.types/nullptr_t.pass.cpp
+++ b/libcxx/test/std/language.support/support.types/nullptr_t.pass.cpp
@@ -74,7 +74,7 @@ void test_nullptr_conversions() {
 #endif
 
 
-int main()
+int main(int, char**)
 {
     static_assert(sizeof(std::nullptr_t) == sizeof(void*),
                   "sizeof(std::nullptr_t) == sizeof(void*)");
@@ -103,4 +103,6 @@ int main()
         test_comparisons<void(*)()>();
     }
     test_nullptr_conversions();
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.types/nullptr_t_integral_cast.fail.cpp b/libcxx/test/std/language.support/support.types/nullptr_t_integral_cast.fail.cpp
index e6dc3772b00259d2a2ffb767bd1e57b62539f864..5802e46f1b8f68c7bab9eed8308d5ca23a4aaa42 100644
--- a/libcxx/test/std/language.support/support.types/nullptr_t_integral_cast.fail.cpp
+++ b/libcxx/test/std/language.support/support.types/nullptr_t_integral_cast.fail.cpp
@@ -10,7 +10,9 @@
 
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     std::ptrdiff_t i = static_cast<std::ptrdiff_t>(nullptr);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.types/nullptr_t_integral_cast.pass.cpp b/libcxx/test/std/language.support/support.types/nullptr_t_integral_cast.pass.cpp
index ab1f447cdc6f1be97217c2956a77dc233447c4a8..b7696df974be15e1bf7d7f009289dbaffd9653f1 100644
--- a/libcxx/test/std/language.support/support.types/nullptr_t_integral_cast.pass.cpp
+++ b/libcxx/test/std/language.support/support.types/nullptr_t_integral_cast.pass.cpp
@@ -16,8 +16,10 @@
 #include <cstddef>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::ptrdiff_t i = reinterpret_cast<std::ptrdiff_t>(nullptr);
     assert(i == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.types/offsetof.pass.cpp b/libcxx/test/std/language.support/support.types/offsetof.pass.cpp
index 4a9dfac5e54c9992fe036600f7a4df35b7e24287..756f55352ed8ee1931de8a25dc0cca4c3d4a5929 100644
--- a/libcxx/test/std/language.support/support.types/offsetof.pass.cpp
+++ b/libcxx/test/std/language.support/support.types/offsetof.pass.cpp
@@ -21,7 +21,9 @@ struct A
     int x;
 };
 
-int main()
+int main(int, char**)
 {
     static_assert(noexcept(offsetof(A, x)), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.types/ptrdiff_t.pass.cpp b/libcxx/test/std/language.support/support.types/ptrdiff_t.pass.cpp
index 9c6c36f383d35893cf970654e12ad3028bbc36bb..de6f7726fe2926724de8912e42ad0395adedc52b 100644
--- a/libcxx/test/std/language.support/support.types/ptrdiff_t.pass.cpp
+++ b/libcxx/test/std/language.support/support.types/ptrdiff_t.pass.cpp
@@ -15,7 +15,7 @@
 //  2. be the same sizeof as void*.
 //  3. be a signed integral.
 
-int main()
+int main(int, char**)
 {
     static_assert(sizeof(std::ptrdiff_t) == sizeof(void*),
                   "sizeof(std::ptrdiff_t) == sizeof(void*)");
@@ -23,4 +23,6 @@ int main()
                   "std::is_signed<std::ptrdiff_t>::value");
     static_assert(std::is_integral<std::ptrdiff_t>::value,
                   "std::is_integral<std::ptrdiff_t>::value");
+
+  return 0;
 }
diff --git a/libcxx/test/std/language.support/support.types/size_t.pass.cpp b/libcxx/test/std/language.support/support.types/size_t.pass.cpp
index ba1f646737857b05610730c46668dfb7dcd423a0..5c840457b3701626f58653fa19fb81ab149151df 100644
--- a/libcxx/test/std/language.support/support.types/size_t.pass.cpp
+++ b/libcxx/test/std/language.support/support.types/size_t.pass.cpp
@@ -15,7 +15,7 @@
 //  2. be the same sizeof as void*.
 //  3. be an unsigned integral.
 
-int main()
+int main(int, char**)
 {
     static_assert(sizeof(std::size_t) == sizeof(void*),
                   "sizeof(std::size_t) == sizeof(void*)");
@@ -23,4 +23,6 @@ int main()
                   "std::is_unsigned<std::size_t>::value");
     static_assert(std::is_integral<std::size_t>::value,
                   "std::is_integral<std::size_t>::value");
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/c.locales/clocale.pass.cpp b/libcxx/test/std/localization/c.locales/clocale.pass.cpp
index 8217dd74da80cef4a0ca37b1d4a43972b9393b97..d8bd81b2ba3f1ef1f1936151525324dbaddbf507 100644
--- a/libcxx/test/std/localization/c.locales/clocale.pass.cpp
+++ b/libcxx/test/std/localization/c.locales/clocale.pass.cpp
@@ -43,7 +43,7 @@
 #error NULL not defined
 #endif
 
-int main()
+int main(int, char**)
 {
     std::lconv lc;
     ((void)lc); // Prevent unused warning
@@ -51,4 +51,6 @@ int main()
     static_assert((std::is_same<decltype(std::setlocale(0, "")), char*>::value), "");
 #endif
     static_assert((std::is_same<decltype(std::localeconv()), std::lconv*>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/compare.pass.cpp b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/compare.pass.cpp
index 33a94f9900de4e7e569b475b23ec4510b896beb0..1d76fa6094f0ed6f4aec59aaf016697291c361f0 100644
--- a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/compare.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/compare.pass.cpp
@@ -32,7 +32,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(LOCALE_en_US_UTF_8);
@@ -68,4 +68,6 @@ int main()
                              s3.data(), s3.data() + s3.size()) == 1);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/hash.pass.cpp b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/hash.pass.cpp
index 21cf03681ee411e8799a4bf1d72fe05a6df73be8..40c15d6e9f4ee980dddbe1e9537f05a9afc238de 100644
--- a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/hash.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/hash.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     std::locale l(LOCALE_en_US_UTF_8);
     {
@@ -39,4 +39,6 @@ int main()
         assert(f.hash(x1.data(), x1.data() + x1.size())
             != f.hash(x2.data(), x2.data() + x2.size()));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/transform.pass.cpp b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/transform.pass.cpp
index 7cd3d0fe5e2cdf14ff06f1ecdd1d33fa71b2b8df..0b86979f55d2ff687fc23ebc8091dcb0b4d8f574 100644
--- a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/transform.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/transform.pass.cpp
@@ -25,7 +25,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(LOCALE_en_US_UTF_8);
@@ -53,4 +53,6 @@ int main()
             assert(f.transform(x.data(), x.data() + x.size()) == x);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/types.pass.cpp b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/types.pass.cpp
index f00c8fd959dbff39a72b99e5d428cdd6bf83f9d1..f4dfd652227a6e8de0d312254aec2efbf4b3118d 100644
--- a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/types.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/types.pass.cpp
@@ -30,7 +30,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     std::locale l(LOCALE_en_US_UTF_8);
     {
@@ -43,4 +43,6 @@ int main()
         assert(&std::use_facet<std::collate<wchar_t> >(l)
             == &std::use_facet<std::collate_byname<wchar_t> >(l));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/ctor.pass.cpp b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/ctor.pass.cpp
index ded9ebae3ad1478747d30f60067469dbe02dad41..856074d391ba7aa43acdc5e42828c86470841e82 100644
--- a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/ctor.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/ctor.pass.cpp
@@ -31,7 +31,7 @@ public:
 
 template <class C> int my_facet<C>::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet<char>);
@@ -63,4 +63,6 @@ int main()
         assert(my_facet<wchar_t>::count == 1);
     }
     assert(my_facet<wchar_t>::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.members/compare.pass.cpp b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.members/compare.pass.cpp
index ff5aa4bddc407f03dc0be3bbb6d439e67f33d29f..bfbbebe398552840b97262d9d8b1f89ef10175cf 100644
--- a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.members/compare.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.members/compare.pass.cpp
@@ -16,7 +16,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -45,4 +45,6 @@ int main()
         assert(f.compare(ib+1, ib+3, ia, ia+sa) == 1);
         assert(f.compare(ia, ia+3, ib, ib+3) == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.members/hash.pass.cpp b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.members/hash.pass.cpp
index 61d5a640f365cd9b0d96c8adccb705d841a3e0ef..07e29b17f6197aa7f2681ca000b0acedaf35eefd 100644
--- a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.members/hash.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.members/hash.pass.cpp
@@ -18,7 +18,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -35,4 +35,6 @@ int main()
         assert(f.hash(x1.data(), x1.data() + x1.size())
             != f.hash(x2.data(), x2.data() + x2.size()));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.members/transform.pass.cpp b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.members/transform.pass.cpp
index 7b8c9915f28a83a01e695f7c76584f55fdad25e1..7588a82be4133d5bfd76dd77c6e0d8357dad3171 100644
--- a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.members/transform.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.members/transform.pass.cpp
@@ -16,7 +16,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -29,4 +29,6 @@ int main()
         const std::collate<wchar_t>& f = std::use_facet<std::collate<wchar_t> >(l);
         assert(f.transform(x.data(), x.data() + x.size()) == x);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.virtuals/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.virtuals/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.virtuals/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.virtuals/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/types.pass.cpp b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/types.pass.cpp
index 45957c3be28b04d6fc2034626463a58e867a5291..63e2739f4e6ad9d12d9e3deb2cabdc1f8a60ac1a 100644
--- a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/types.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/types.pass.cpp
@@ -22,7 +22,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -47,4 +47,6 @@ int main()
         static_assert((std::is_same<std::collate<wchar_t>::string_type, std::wstring>::value), "");
         static_assert((std::is_base_of<std::locale::facet, std::collate<wchar_t> >::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.collate/nothing_to_do.pass.cpp b/libcxx/test/std/localization/locale.categories/category.collate/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locale.categories/category.collate/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.collate/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/ctype_base.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/ctype_base.pass.cpp
index 92024149c0895cc4a007e286b1550639fbee7624..b7da91b4686cf0c322ad381cadf55a0cbe1c1865 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/ctype_base.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/ctype_base.pass.cpp
@@ -38,7 +38,7 @@
 template <class T>
 void test(const T &) {}
 
-int main()
+int main(int, char**)
 {
     assert(std::ctype_base::space);
     assert(std::ctype_base::print);
@@ -74,4 +74,6 @@ int main()
     test(std::ctype_base::blank);
     test(std::ctype_base::alnum);
     test(std::ctype_base::graph);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.dtor/dtor.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.dtor/dtor.pass.cpp
index 5ba7a67e40cb2792410106b6858dedf44b14db72..e38af450f7fb786647a5dfc33efa3208f4c84b02 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.dtor/dtor.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.dtor/dtor.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "count_new.hpp"
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new std::ctype<char>);
@@ -36,4 +36,6 @@ int main()
         assert(globalMemCounter.checkDeleteArrayCalledEq(0));
     }
     assert(globalMemCounter.checkDeleteArrayCalledEq(1));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/ctor.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/ctor.pass.cpp
index 20eef3354c58bc6f787606029e7e6ca76fd8feda..4ec37db021a45e7f585b65f26168c48fc31ceb97 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/ctor.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/ctor.pass.cpp
@@ -29,7 +29,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet);
@@ -46,4 +46,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/is_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/is_1.pass.cpp
index c4561f7964f3a16d71cf61ceb8f2e2395fc186e1..562f6c25e6b93c7a172563b3bdc117512aaf61c3 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/is_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/is_1.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -55,4 +55,6 @@ int main()
         assert(f.is(F::graph, '.'));
         assert(!f.is(F::graph,  '\x07'));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/is_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/is_many.pass.cpp
index 9415d8b5a7d93528c85a7c2c99040f2288a68a34..c073a955e78b2cd7ff5ab63986d3cadda3aba854 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/is_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/is_many.pass.cpp
@@ -19,7 +19,7 @@
 
 #include <stdio.h>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -114,4 +114,6 @@ int main()
         assert( (m[5] & F::alnum));
         assert( (m[5] & F::graph));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/narrow_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/narrow_1.pass.cpp
index b0fa41a2f3dd0acb0042f19d2981381fd4a938cd..d2fa02201a3eb8645290fcd2c55e842e93cd1312 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/narrow_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/narrow_1.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -29,4 +29,6 @@ int main()
         assert(f.narrow('a', '*') == 'a');
         assert(f.narrow('1', '*') == '1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/narrow_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/narrow_many.pass.cpp
index 01bb80534566e0c5dd209890783beb87ea8650a8..4814695403579a136c388427ae21f4836ab06117 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/narrow_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/narrow_many.pass.cpp
@@ -17,7 +17,7 @@
 #include <vector>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -34,4 +34,6 @@ int main()
         assert(v[4] == 'a');
         assert(v[5] == '1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/scan_is.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/scan_is.pass.cpp
index 3f4f049020535522a280a28d299495e21842055f..043ca679608c0ecdecbbdb409be0654beaf55ece 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/scan_is.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/scan_is.pass.cpp
@@ -19,7 +19,7 @@
 
 #include <stdio.h>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -40,4 +40,6 @@ int main()
         assert(f.scan_is(F::alnum, in.data(), in.data() + in.size()) - in.data() == 1);
         assert(f.scan_is(F::graph, in.data(), in.data() + in.size()) - in.data() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/scan_not.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/scan_not.pass.cpp
index 6cd24a82e07bf69262f2d15c12cafafd426f9c41..066a06a7f4c51a63e74a2d29afd7ecbd941fc2f9 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/scan_not.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/scan_not.pass.cpp
@@ -19,7 +19,7 @@
 
 #include <stdio.h>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -40,4 +40,6 @@ int main()
         assert(f.scan_not(F::alnum, in.data(), in.data() + in.size()) - in.data() == 0);
         assert(f.scan_not(F::graph, in.data(), in.data() + in.size()) - in.data() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/table.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/table.pass.cpp
index 9d815196b185512ce65b6ee2409517464881e1da..6a0fea0b1fde4e929662ebf7a5d6d0cf85d0ae37 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/table.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/table.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::ctype<char> F;
     {
@@ -29,4 +29,6 @@ int main()
         const F& f = std::use_facet<F>(l);
         assert(f.table() == table);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/tolower_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/tolower_1.pass.cpp
index 2b817002ce7f223f36357805ccfbd5b9f4c846d5..ddf4fbdb057f6d79423b587daeae5fe22aac382d 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/tolower_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/tolower_1.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -29,4 +29,6 @@ int main()
         assert(f.tolower('a') == 'a');
         assert(f.tolower('1') == '1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/tolower_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/tolower_many.pass.cpp
index 036ed25c6a3e2a17511177c18a62f0f01718d6cc..b307d4627355003c53034235e745da921c09190d 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/tolower_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/tolower_many.pass.cpp
@@ -16,7 +16,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -32,4 +32,6 @@ int main()
         assert(in[4] == 'a');
         assert(in[5] == '1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/toupper_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/toupper_1.pass.cpp
index c393bb91b8e2be6a97649b4d0edc9579118c69f1..8b5505910eeb29ffbfce6af22545ca07da78d0a8 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/toupper_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/toupper_1.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -29,4 +29,6 @@ int main()
         assert(f.toupper('a') == 'A');
         assert(f.toupper('1') == '1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/toupper_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/toupper_many.pass.cpp
index 25af985f7c8f768c560c151ba5c72714637a67e1..3d1c453cf39835c18121a28d89c72ff88991879e 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/toupper_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/toupper_many.pass.cpp
@@ -16,7 +16,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -32,4 +32,6 @@ int main()
         assert(in[4] == 'A');
         assert(in[5] == '1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/widen_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/widen_1.pass.cpp
index 5b9f74bad918a8524867b16a86f7290de62364e2..81c3ab6b3c41fef7400c6a0a1f3f58a4e06cd9d8 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/widen_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/widen_1.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -29,4 +29,6 @@ int main()
         assert(f.widen('a') == 'a');
         assert(f.widen('1') == '1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/widen_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/widen_many.pass.cpp
index ab3a838c087a30fa253c354638a7281f4c44bda5..35d9335c252f81a01943e2ac391b40257f91262f 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/widen_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/widen_many.pass.cpp
@@ -17,7 +17,7 @@
 #include <vector>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -34,4 +34,6 @@ int main()
         assert(v[4] == 'a');
         assert(v[5] == '1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.statics/classic_table.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.statics/classic_table.pass.cpp
index 1aef57d3fb75f3427dbe483de502812db3866da8..7f46238d68246dde65234aff7a94df73ea76cb52 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.statics/classic_table.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.statics/classic_table.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::ctype<char> F;
     assert(F::classic_table() != 0);
@@ -55,4 +55,6 @@ int main()
         assert(((p[i] & ~set) & defined) == 0);   // no extra ones
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.virtuals/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.virtuals/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.virtuals/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.virtuals/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/types.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/types.pass.cpp
index b23f9ef83d82276e2ac90570d3e518cb550b750d..c46dbb3e6f108c1fd46dee25c120a85a754b2496 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/types.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/types.pass.cpp
@@ -21,7 +21,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -35,4 +35,6 @@ int main()
         static_assert((std::is_base_of<std::ctype_base, std::ctype<char> >::value), "");
         static_assert((std::is_base_of<std::locale::facet, std::ctype<char> >::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_char.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_char.pass.cpp
index d5cde47545388c1d6ea19c5b9b8f62380c4fea8a..03d17375e5e527d107effd0ffa43613fdd068132 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_char.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_char.pass.cpp
@@ -36,7 +36,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet(LOCALE_en_US));
@@ -68,4 +68,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_char16_t.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_char16_t.pass.cpp
index 4d2803815de97651a54e8c6dc95d4db72da678cf..eedf192db26937443cc38bbdb419b32fb7640017 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_char16_t.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_char16_t.pass.cpp
@@ -34,7 +34,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet("en_US"));
@@ -66,4 +66,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_char32_t.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_char32_t.pass.cpp
index 50bf5834902d795b411f7bd90ce38a155ab600c1..8e5d70356ab2d09e526b39ad0272103dd240dd7a 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_char32_t.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_char32_t.pass.cpp
@@ -34,7 +34,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet("en_US"));
@@ -66,4 +66,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_wchar_t.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_wchar_t.pass.cpp
index 2379b163151f1b0e0b6b4b9d712a556510605217..5503192ca98b48239ab01aa2a1c66c0a83da68fe 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_wchar_t.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_wchar_t.pass.cpp
@@ -38,7 +38,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet(LOCALE_en_US_UTF_8));
@@ -70,4 +70,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/codecvt_base.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/codecvt_base.pass.cpp
index f6b94c5f18574d373c7c4768e9486dd57acf1522..c2e40542e0eac1f49eb51ab6fc4a3bc5904105f4 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/codecvt_base.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/codecvt_base.pass.cpp
@@ -17,10 +17,12 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert(std::codecvt_base::ok == 0);
     assert(std::codecvt_base::partial == 1);
     assert(std::codecvt_base::error == 2);
     assert(std::codecvt_base::noconv == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_char.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_char.pass.cpp
index e12d301686c57d899e45d2059ac74727c0cb291c..3f0dc9e7cc191bf3182fb7d2a20befb37e532c87 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_char.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_char.pass.cpp
@@ -31,7 +31,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet);
@@ -48,4 +48,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_char16_t.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_char16_t.pass.cpp
index e0ed00dfd6169db490eccf2e649063c588c859d9..e2df342d4e6b9eb5d5fdd689cea0ed92bd886366 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_char16_t.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_char16_t.pass.cpp
@@ -35,7 +35,7 @@ int my_facet::count = 0;
 
 //#endif
 
-int main()
+int main(int, char**)
 {
 //#ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
     {
@@ -54,4 +54,6 @@ int main()
     }
     assert(my_facet::count == 0);
 //#endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_char32_t.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_char32_t.pass.cpp
index 56d63764df6051a4d8615ce7c67310e30707f3fb..0df7f3515df720a1da2258154b7afb375d87f795 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_char32_t.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_char32_t.pass.cpp
@@ -35,7 +35,7 @@ int my_facet::count = 0;
 
 //#endif
 
-int main()
+int main(int, char**)
 {
 //#ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
     {
@@ -54,4 +54,6 @@ int main()
     }
     assert(my_facet::count == 0);
 //#endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_wchar_t.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_wchar_t.pass.cpp
index 8f4293ee83b135eb74662c1bf70153646c1e2f4e..6917e1b72206e904f5e1c07385404d13982d9342 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_wchar_t.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_wchar_t.pass.cpp
@@ -31,7 +31,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet);
@@ -48,4 +48,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_always_noconv.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_always_noconv.pass.cpp
index 2f84eb6c92b6c284316c652d2b711b359df770ab..e1741aec05e4baab5419572c8e8f61c309d2c0d3 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_always_noconv.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_always_noconv.pass.cpp
@@ -17,9 +17,11 @@
 
 typedef std::codecvt<char16_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
     assert(!f.always_noconv());
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_encoding.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_encoding.pass.cpp
index 4a30c4ee8f9c5e32a63bea58a041668e8a0157a1..f4614984ad74b122b7344caa5912c319007bb0b7 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_encoding.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_encoding.pass.cpp
@@ -17,9 +17,11 @@
 
 typedef std::codecvt<char16_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
     assert(f.encoding() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_in.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_in.pass.cpp
index 6a883d3d44fe9ed7fa46728505825d8d39d5cbc9..2a6a07ef95768802b8941b14751bebb1a7e84507 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_in.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_in.pass.cpp
@@ -21,7 +21,7 @@
 
 typedef std::codecvt<char16_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const char from[] = "some text";
@@ -36,4 +36,6 @@ int main()
     assert(to_next - to == 9);
     for (unsigned i = 0; i < 9; ++i)
         assert(to[i] == from[i]);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_length.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_length.pass.cpp
index a48b902e1ddd64d2f0b19313215af8c3853c2146..038ae971136cf7533449975aa6523340c4a32f3c 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_length.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_length.pass.cpp
@@ -17,7 +17,7 @@
 
 typedef std::codecvt<char16_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
@@ -28,4 +28,6 @@ int main()
     assert(f.length(mbs, from, from+10, 9) == 9);
     assert(f.length(mbs, from, from+10, 10) == 10);
     assert(f.length(mbs, from, from+10, 100) == 10);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_max_length.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_max_length.pass.cpp
index 69c711f60a34bf769adc27cf6b7575197b9bc077..bcaa7052876dc886eab520f6c007df2a468905d9 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_max_length.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_max_length.pass.cpp
@@ -17,9 +17,11 @@
 
 typedef std::codecvt<char16_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
     assert(f.max_length() == 4);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_out.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_out.pass.cpp
index 9b5d0f988ab2c2000fe868769ae7da3330f4a3c7..cff42b0c0549269df72ebd1387b35b79706f6e0b 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_out.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_out.pass.cpp
@@ -23,7 +23,7 @@
 
 typedef std::codecvt<char16_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
@@ -41,4 +41,6 @@ int main()
         for (unsigned i = 0; i < 9; ++i)
             assert(to[i] == from[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_unshift.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_unshift.pass.cpp
index bde44c0889ad096804f2a37aa3f025db8708d003..5b027bae7b5b358b5d6f3301f95c4f9cdbe33bfc 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_unshift.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_unshift.pass.cpp
@@ -20,7 +20,7 @@
 
 typedef std::codecvt<char16_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     std::vector<char> to(3);
@@ -29,4 +29,6 @@ int main()
     char* to_next = 0;
     assert(f.unshift(mbs, to.data(), to.data() + to.size(), to_next) == F::noconv);
     assert(to_next == to.data());
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_always_noconv.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_always_noconv.pass.cpp
index 2ef1e5c657ddbf9b47a688d0f1ef04538314a332..2b2f136e3b44c4ed050ebc9bdf04f89a554146a6 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_always_noconv.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_always_noconv.pass.cpp
@@ -17,9 +17,11 @@
 
 typedef std::codecvt<char32_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
     assert(!f.always_noconv());
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_encoding.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_encoding.pass.cpp
index 834bd607689d0645dea013c4c04477a472130fc7..0d2f35fc2c2a48ec231763056d008752f3f74d9c 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_encoding.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_encoding.pass.cpp
@@ -17,9 +17,11 @@
 
 typedef std::codecvt<char32_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
     assert(f.encoding() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_in.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_in.pass.cpp
index 8472a569226a1d7cc4f26f4af8d294b2584a92e5..eb7c53fcea6a04dbe39584c558678f6fca8d03db 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_in.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_in.pass.cpp
@@ -21,7 +21,7 @@
 
 typedef std::codecvt<char32_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const char from[] = "some text";
@@ -36,4 +36,6 @@ int main()
     assert(to_next - to == 9);
     for (unsigned i = 0; i < 9; ++i)
         assert(to[i] == static_cast<char32_t>(from[i]));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_length.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_length.pass.cpp
index 6986314e3f4a3a42660732aa9a600e4d88fd62ec..da853068883b0bbea3073320ac1537cff2230a24 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_length.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_length.pass.cpp
@@ -17,7 +17,7 @@
 
 typedef std::codecvt<char32_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
@@ -28,4 +28,6 @@ int main()
     assert(f.length(mbs, from, from+10, 9) == 9);
     assert(f.length(mbs, from, from+10, 10) == 10);
     assert(f.length(mbs, from, from+10, 100) == 10);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_max_length.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_max_length.pass.cpp
index 921ec18549c3b46bcf7b47a97e267f41c4ba42f0..f31dba747c78be60a72b97cafd9b659f4d81fe1e 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_max_length.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_max_length.pass.cpp
@@ -17,9 +17,11 @@
 
 typedef std::codecvt<char32_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
     assert(f.max_length() == 4);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_out.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_out.pass.cpp
index 210f8c052e57df7b2dadc6cde36d622bfb85295e..7ed5609436c486411f3469298464a1c8f8912087 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_out.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_out.pass.cpp
@@ -23,7 +23,7 @@
 
 typedef std::codecvt<char32_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
@@ -41,4 +41,6 @@ int main()
         for (unsigned i = 0; i < 9; ++i)
             assert(static_cast<char32_t>(to[i]) == from[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_unshift.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_unshift.pass.cpp
index 26981d3c85c1f5dc7749c019c23fe51acda65cbf..aaf9a6a20e698025b1435e509407137c6e46b85a 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_unshift.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_unshift.pass.cpp
@@ -20,7 +20,7 @@
 
 typedef std::codecvt<char32_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     std::vector<char> to(3);
@@ -29,4 +29,6 @@ int main()
     char* to_next = 0;
     assert(f.unshift(mbs, to.data(), to.data() + to.size(), to_next) == F::noconv);
     assert(to_next == to.data());
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_always_noconv.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_always_noconv.pass.cpp
index 2590c2b0e62b23995b97d80dfe518e6e41de4bba..c253bbed72f42e793f8d767ec36884d84e01cb6e 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_always_noconv.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_always_noconv.pass.cpp
@@ -17,9 +17,11 @@
 
 typedef std::codecvt<char, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
     assert(f.always_noconv());
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_encoding.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_encoding.pass.cpp
index 571ab84d8881a704b586611ac68f27b7268918d4..79c26add6ab68a95f96076c9a410cb69594ec841 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_encoding.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_encoding.pass.cpp
@@ -17,9 +17,11 @@
 
 typedef std::codecvt<char, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
     assert(f.encoding() == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_in.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_in.pass.cpp
index 2b7c610e461d4366cdaf023bfe5dfc1ee32402e1..1f2cdb6be4587fbf0f51f84c4a76afddf58ddcd8 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_in.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_in.pass.cpp
@@ -21,7 +21,7 @@
 
 typedef std::codecvt<char, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const std::basic_string<F::intern_type> from("some text");
@@ -34,4 +34,6 @@ int main()
                      to.data(), to.data() + to.size(), to_next) == F::noconv);
     assert(from_next == from.data());
     assert(to_next == to.data());
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_length.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_length.pass.cpp
index b930009b5169e53fc2bd6671a794ea6090eb8441..ad45cba5f43420736c965f5f2fc38e981ebabe2b 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_length.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_length.pass.cpp
@@ -17,7 +17,7 @@
 
 typedef std::codecvt<char, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
@@ -28,4 +28,6 @@ int main()
     assert(f.length(mbs, from, from+10, 10) == 10);
     assert(f.length(mbs, from, from+10, 11) == 10);
     assert(f.length(mbs, from, from+10, 100) == 10);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_max_length.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_max_length.pass.cpp
index adc0b1707b1685a8e0b0f09b8f4b40b296513822..437e72b94cad46742991ee02affed27b1402459b 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_max_length.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_max_length.pass.cpp
@@ -17,9 +17,11 @@
 
 typedef std::codecvt<char, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
     assert(f.max_length() == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_out.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_out.pass.cpp
index 28b4be7455bd2e4c8026b7b07cf20ff2f2b9e0d4..be266746cdab357aa0116b24028925b939e98cda 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_out.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_out.pass.cpp
@@ -21,7 +21,7 @@
 
 typedef std::codecvt<char, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const std::basic_string<F::intern_type> from("some text");
@@ -34,4 +34,6 @@ int main()
                       to.data(), to.data() + to.size(), to_next) == F::noconv);
     assert(from_next == from.data());
     assert(to_next == to.data());
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_unshift.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_unshift.pass.cpp
index 56c10aa52e463007613d5e288f9f8268c1c3eb11..a3d9e3d14bdf3c34831e8d988ad3b642a2112100 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_unshift.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_unshift.pass.cpp
@@ -20,7 +20,7 @@
 
 typedef std::codecvt<char, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     std::vector<char> to(3);
@@ -29,4 +29,6 @@ int main()
     char* to_next = 0;
     assert(f.unshift(mbs, to.data(), to.data() + to.size(), to_next) == F::noconv);
     assert(to_next == to.data());
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/utf_sanity_check.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/utf_sanity_check.pass.cpp
index 2d338dd8ee05440c145f5257c96bc577b3861c30..eaae7b6e97bde06a6479afd881ddc888dc1a3dd6 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/utf_sanity_check.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/utf_sanity_check.pass.cpp
@@ -20,7 +20,7 @@
 
 #include <stdio.h>
 
-int main()
+int main(int, char**)
 {
     typedef std::codecvt<char32_t, char, std::mbstate_t> F32_8;
     typedef std::codecvt<char16_t, char, std::mbstate_t> F16_8;
@@ -123,4 +123,6 @@ int main()
             assert(c32 == c32x);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_always_noconv.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_always_noconv.pass.cpp
index df645174767312e828de55dbda742602be0a29d0..484b2213d24bd83b3c1aeaf2a0d78dd40544b6af 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_always_noconv.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_always_noconv.pass.cpp
@@ -17,9 +17,11 @@
 
 typedef std::codecvt<wchar_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
     assert(!f.always_noconv());
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_encoding.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_encoding.pass.cpp
index ed33018b274fbd2aec48c0fe9991404a7ec3c417..9c075af1372881d21e0e6bc780811d650ad17c44 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_encoding.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_encoding.pass.cpp
@@ -17,9 +17,11 @@
 
 typedef std::codecvt<wchar_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
     assert(f.encoding() == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_in.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_in.pass.cpp
index 7ca632e4e5e63dffa8e08e09dbd355cdd5fb618c..bec0e6cb0ac75cd44fe81473dd1b5d6947c0a583 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_in.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_in.pass.cpp
@@ -22,7 +22,7 @@
 
 typedef std::codecvt<wchar_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const std::basic_string<F::extern_type> from("some text");
@@ -39,4 +39,6 @@ int main()
     assert(static_cast<std::size_t>(to_next - to.data()) == expected.size());
     assert(static_cast<std::size_t>(to_next - to.data()) == expected.size());
     assert(to == expected);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_length.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_length.pass.cpp
index 0fcab1af7ae2f514bade1f49c5c9a2477ca7f3da..4fd5d32938662a95cd3cd954e6f25be384e96ce9 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_length.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_length.pass.cpp
@@ -17,7 +17,7 @@
 
 typedef std::codecvt<wchar_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
@@ -28,4 +28,6 @@ int main()
     assert(f.length(mbs, from, from+10, 10) == 10);
     assert(f.length(mbs, from, from+10, 11) == 10);
     assert(f.length(mbs, from, from+10, 100) == 10);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_max_length.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_max_length.pass.cpp
index fefd11016fed5b74771c0cde8f6ecea240fbc14d..90d91315197f283107ea2026f7ddf6b091ef2539 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_max_length.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_max_length.pass.cpp
@@ -17,9 +17,11 @@
 
 typedef std::codecvt<wchar_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
     assert(f.max_length() == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_out.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_out.pass.cpp
index 8769b88146926eda23d87cc88e8e33dac190aeb4..bc12bdbce646eed3fae35f68552aef9290d231ac 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_out.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_out.pass.cpp
@@ -23,7 +23,7 @@
 
 typedef std::codecvt<wchar_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
@@ -67,4 +67,6 @@ int main()
         assert(static_cast<std::size_t>(to_next - to.data()) == to.size()-1);
         assert(to.data() == std::string("some te"));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_unshift.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_unshift.pass.cpp
index 9241c7a47026a2e5d8228960925c237028443c4e..e0f7c3c9520e8edecb6e4df9c84a28adee76812e 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_unshift.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_unshift.pass.cpp
@@ -22,7 +22,7 @@
 
 typedef std::codecvt<wchar_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     std::vector<F::extern_type> to(3);
@@ -31,4 +31,6 @@ int main()
     F::extern_type* to_next = 0;
     assert(f.unshift(mbs, to.data(), to.data() + to.size(), to_next) == F::ok);
     assert(to_next == to.data());
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.virtuals/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.virtuals/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.virtuals/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.virtuals/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_char.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_char.pass.cpp
index 12fee2682dabe37b131a723558d2c8eddfa2fcdc..455cf03ee716154f8ca460f97b4ea41bd8c520c5 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_char.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_char.pass.cpp
@@ -24,7 +24,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::codecvt<char, char, std::mbstate_t> F;
     static_assert((std::is_base_of<std::locale::facet, F>::value), "");
@@ -37,4 +37,6 @@ int main()
     const F& f = std::use_facet<F>(l);
     ((void)f); // Prevent unused warning
     (void)F::id;
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_char16_t.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_char16_t.pass.cpp
index b01bd5a7abd502e723195767f60a47ee8493648d..f52c60f1bfd3900677f8e46c6d166a270297a805 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_char16_t.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_char16_t.pass.cpp
@@ -24,7 +24,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::codecvt<char16_t, char, std::mbstate_t> F;
     static_assert((std::is_base_of<std::locale::facet, F>::value), "");
@@ -37,4 +37,6 @@ int main()
     const F& f = std::use_facet<F>(l);
     (void)F::id;
     ((void)f);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_char32_t.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_char32_t.pass.cpp
index 6ad4697542dc5dd15ac4209f1a453cffb0361468..c75de419c8675126b3cc09a05bff881c1d0c0686 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_char32_t.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_char32_t.pass.cpp
@@ -24,7 +24,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::codecvt<char32_t, char, std::mbstate_t> F;
     static_assert((std::is_base_of<std::locale::facet, F>::value), "");
@@ -37,4 +37,6 @@ int main()
     const F& f = std::use_facet<F>(l);
     (void)F::id;
     ((void)f);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_wchar_t.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_wchar_t.pass.cpp
index 6c19e41a8e44734f5bb6d0de016ebd195da00722..07e25be718c3e45dd960b55efc2f3e58864d9f82 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_wchar_t.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_wchar_t.pass.cpp
@@ -24,7 +24,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::codecvt<wchar_t, char, std::mbstate_t> F;
     static_assert((std::is_base_of<std::locale::facet, F>::value), "");
@@ -37,4 +37,6 @@ int main()
     const F& f = std::use_facet<F>(l);
     ((void)f); // Prevent unused warning
     (void)F::id;
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/is_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/is_1.pass.cpp
index 32acd85d18bb48f9afc0c6ce2f3bcc0307285e99..3331c5a67d8033e32882fe75c695b6c889b5bc35 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/is_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/is_1.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(LOCALE_en_US_UTF_8);
@@ -108,4 +108,6 @@ int main()
             assert(!f.is(F::upper, L'\x00DA'));
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/is_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/is_many.pass.cpp
index 1087b88c0c2b6fcc88642ad2734aad89b6734da9..6751fd60de0b15b47727fa95bf1f2e9c8f47cfd1 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/is_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/is_many.pass.cpp
@@ -23,7 +23,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(LOCALE_en_US_UTF_8);
@@ -243,4 +243,6 @@ int main()
             assert( (m[6] & F::graph));
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/mask.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/mask.pass.cpp
index 45d90ddd540fe05ccf3d01767c3eef530269da51..3a6360eb9dee8a23d6d67d9be396a3806c39f8c8 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/mask.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/mask.pass.cpp
@@ -16,7 +16,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l("C");
@@ -49,4 +49,6 @@ int main()
             assert( cf.is(CF::alpha,  'a'));
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/narrow_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/narrow_1.pass.cpp
index 19d751d29956b2bb2cc5e4b1322e9c8fef5b1a57..6d19377250194f081774bb114bb88e3d18f25c54 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/narrow_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/narrow_1.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::string(LOCALE_fr_CA_ISO8859_1));
@@ -52,4 +52,6 @@ int main()
             assert(f.narrow(L'\xDA', '*') == '*');
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/narrow_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/narrow_many.pass.cpp
index c51b97311a15da9f2611334cda03e595a41fee22..7ab4874fbcd3abf64b46583d754a0fe0157a5b8b 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/narrow_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/narrow_many.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(LOCALE_fr_CA_ISO8859_1);
@@ -60,4 +60,6 @@ int main()
             assert(v[6] == '*');
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/scan_is.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/scan_is.pass.cpp
index 6c875863fb5b74d0c942ad3985c11ff784a2cbb1..b736dd7862c8d250085e159ec15db27bf29466c3 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/scan_is.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/scan_is.pass.cpp
@@ -23,7 +23,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(LOCALE_en_US_UTF_8);
@@ -67,4 +67,6 @@ int main()
             assert(f.scan_is(F::graph, in.data(), in.data() + in.size()) - in.data() == 2);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/scan_not.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/scan_not.pass.cpp
index dbeeae4c6991ab40d1e8ded68e31a5b2d32eae8d..fa7674a8ca0855653af939125a2b26cfbd625819 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/scan_not.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/scan_not.pass.cpp
@@ -23,7 +23,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(LOCALE_en_US_UTF_8);
@@ -67,4 +67,6 @@ int main()
             assert(f.scan_not(F::graph, in.data(), in.data() + in.size()) - in.data() == 0);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/tolower_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/tolower_1.pass.cpp
index 3f9ab9dce271781a1835473a76c3ad5c06a9bda2..ab5daa7aa3886347859c7c3c8e11824f27b2ac38 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/tolower_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/tolower_1.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l;
@@ -88,4 +88,6 @@ int main()
             assert(f.tolower(L'\xFA') == L'\xFA');
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/tolower_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/tolower_many.pass.cpp
index 29021e0f4cef8614f7e36906bf1e46da3959ba2c..29403cb10101bb7f0cf99c691ade36884e574298 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/tolower_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/tolower_many.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l;
@@ -94,4 +94,6 @@ int main()
             assert(in[6] == L'1');
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/toupper_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/toupper_1.pass.cpp
index b9c882c9a7482e184d53eec4e6a0e3a721f025d8..56304a7558aa6df18503f72796998db34063c8fa 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/toupper_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/toupper_1.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l;
@@ -90,4 +90,6 @@ int main()
             assert(f.toupper(L'\xFA') == L'\xFA');
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/toupper_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/toupper_many.pass.cpp
index 2b0669cb30e22cc95822f70d7b9a837ee2f45e8f..bfc3bf848ad105b5637f433bae28b44b746943b1 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/toupper_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/toupper_many.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l;
@@ -94,4 +94,6 @@ int main()
             assert(in[6] == L'1');
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/types.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/types.pass.cpp
index 9ec94681611b351c19ffefdbbd6880b427624f11..ce0a0e30ed6cce17204bbaa22b370709d1a2e1ad 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/types.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/types.pass.cpp
@@ -28,7 +28,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(LOCALE_en_US_UTF_8);
@@ -56,4 +56,6 @@ int main()
                 == &std::use_facet<std::ctype_byname<wchar_t> >(l));
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/widen_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/widen_1.pass.cpp
index 5752bb82bb8e773c62c27cc74a642b2fccbc1afe..1dc9b7de805669240835bb58d933417e96a63c01 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/widen_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/widen_1.pass.cpp
@@ -23,7 +23,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l;
@@ -61,4 +61,6 @@ int main()
 #endif
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/widen_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/widen_many.pass.cpp
index 4f5efca1d66d01eeb03cddee7d6e2c93db2f6916..67a97ba68265da1e8a9400a3a891a5f1dee8b6b2 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/widen_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/widen_many.pass.cpp
@@ -23,7 +23,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(LOCALE_en_US_UTF_8);
@@ -67,4 +67,6 @@ int main()
 #endif
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/ctor.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/ctor.pass.cpp
index e41b93b78a29ef53970bba276c7e1860044f4bac..f53d4e9645d35d7f56e5a650a941ddb62d9fe46c 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/ctor.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/ctor.pass.cpp
@@ -30,7 +30,7 @@ public:
 
 template <class C> int my_facet<C>::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet<wchar_t>);
@@ -47,4 +47,6 @@ int main()
         assert(my_facet<wchar_t>::count == 1);
     }
     assert(my_facet<wchar_t>::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/is_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/is_1.pass.cpp
index a48f75f4f7db6ae1d1d736c280a59ea060ffd60f..23a1aa9d21a2e65f060ed34bc6984358bb1c1693 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/is_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/is_1.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -55,4 +55,6 @@ int main()
         assert(f.is(F::graph, L'.'));
         assert(!f.is(F::graph,  L'\x07'));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/is_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/is_many.pass.cpp
index f348d208077f6663748afcf55b9bde541e0128e3..d9dd5b58ab4612b9ac6288b4ac08bda9f79c8263 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/is_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/is_many.pass.cpp
@@ -19,7 +19,7 @@
 
 #include <stdio.h>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -114,4 +114,6 @@ int main()
         assert( (m[5] & F::alnum));
         assert( (m[5] & F::graph));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/narrow_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/narrow_1.pass.cpp
index 1e1194bdad8ed4126e87770a8b70bd7be655c250..55e1f378b4397cadb53b5bb9e3f954e4acef1886 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/narrow_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/narrow_1.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -29,4 +29,6 @@ int main()
         assert(f.narrow(L'a', '*') == 'a');
         assert(f.narrow(L'1', '*') == '1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/narrow_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/narrow_many.pass.cpp
index 523fb25034276bbe3443818a0783e077a1500c0f..47c2b51887e3fd937d0b1de2f316c6c0af2bf04e 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/narrow_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/narrow_many.pass.cpp
@@ -17,7 +17,7 @@
 #include <vector>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -34,4 +34,6 @@ int main()
         assert(v[4] == 'a');
         assert(v[5] == '1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/scan_is.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/scan_is.pass.cpp
index 23718fec18a56507ce357c8cdbcbbdc15d8aede7..1891b155b312a160d966ebeb586ff3ba0fe4f873 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/scan_is.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/scan_is.pass.cpp
@@ -19,7 +19,7 @@
 
 #include <stdio.h>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -40,4 +40,6 @@ int main()
         assert(f.scan_is(F::alnum, in.data(), in.data() + in.size()) - in.data() == 1);
         assert(f.scan_is(F::graph, in.data(), in.data() + in.size()) - in.data() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/scan_not.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/scan_not.pass.cpp
index 22bc14701990ca44b971b5e0f1c71404e8410c54..40cc8c0fa0dffe0a3b935cc5b1a0e3dc89d6ee91 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/scan_not.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/scan_not.pass.cpp
@@ -19,7 +19,7 @@
 
 #include <stdio.h>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -40,4 +40,6 @@ int main()
         assert(f.scan_not(F::alnum, in.data(), in.data() + in.size()) - in.data() == 0);
         assert(f.scan_not(F::graph, in.data(), in.data() + in.size()) - in.data() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/tolower_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/tolower_1.pass.cpp
index b5c402de2124c8700a758adddc29915da2315ac5..1ae14410c6f9e57343ec6c7197c44a74f0f66174 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/tolower_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/tolower_1.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -29,4 +29,6 @@ int main()
         assert(f.tolower(L'a') == L'a');
         assert(f.tolower(L'1') == L'1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/tolower_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/tolower_many.pass.cpp
index 92bbc8ceb431bb614d4661f8048e68b9d3b908b1..711343d3c5aa5c5e02aa2e68f8fd0af728b717d2 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/tolower_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/tolower_many.pass.cpp
@@ -16,7 +16,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -32,4 +32,6 @@ int main()
         assert(in[4] == L'a');
         assert(in[5] == L'1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/toupper_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/toupper_1.pass.cpp
index 0ed6e4504fb59061b7e6b03ce1a535231c818a7a..fbc28a1b87cb834411bb6887025d5153eb314460 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/toupper_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/toupper_1.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -29,4 +29,6 @@ int main()
         assert(f.toupper(L'a') == L'A');
         assert(f.toupper(L'1') == L'1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/toupper_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/toupper_many.pass.cpp
index 0510778eb3b1aee970a5edf669a73c7c07f85824..963e894a7e12d147f01a595a1a70f68c11b92b29 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/toupper_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/toupper_many.pass.cpp
@@ -16,7 +16,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -32,4 +32,6 @@ int main()
         assert(in[4] == L'A');
         assert(in[5] == L'1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/widen_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/widen_1.pass.cpp
index 1737de8f0f7dfed939dc9c936b8b1af32d29b25a..c2570a311364383556d1594225481bd3f1aa52c0 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/widen_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/widen_1.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -29,4 +29,6 @@ int main()
         assert(f.widen('a') == L'a');
         assert(f.widen('1') == L'1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/widen_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/widen_many.pass.cpp
index 3942268ebd240fad249103299e890725e9d9fa6c..a43817a25a1c5a05ef9c4c4083018dec9db725fc 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/widen_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/widen_many.pass.cpp
@@ -17,7 +17,7 @@
 #include <vector>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -34,4 +34,6 @@ int main()
         assert(v[4] == L'a');
         assert(v[5] == L'1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.virtuals/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.virtuals/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.virtuals/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.virtuals/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/types.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/types.pass.cpp
index 89ac905a2e5e59d3b32f8640b46d8875cac08cda..35b5d3282b94790f6b78f2b6e354035a64874a00 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/types.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/types.pass.cpp
@@ -21,7 +21,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -35,4 +35,6 @@ int main()
         static_assert((std::is_base_of<std::ctype_base, std::ctype<wchar_t> >::value), "");
         static_assert((std::is_base_of<std::locale::facet, std::ctype<wchar_t> >::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.messages/locale.messages.byname/nothing_to_do.pass.cpp b/libcxx/test/std/localization/locale.categories/category.messages/locale.messages.byname/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locale.categories/category.messages/locale.messages.byname/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.messages/locale.messages.byname/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/ctor.pass.cpp b/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/ctor.pass.cpp
index df42b522c7bb0902d31fb169b967d318168aa45a..ddbbe66694bed455d1c7159868f3d40b541bac53 100644
--- a/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/ctor.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/ctor.pass.cpp
@@ -31,7 +31,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet);
@@ -48,4 +48,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/locale.messages.members/not_testable.pass.cpp b/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/locale.messages.members/not_testable.pass.cpp
index 994a97211a4d3516c2237aaa6349fe79322b3f6e..c0166f80f3429291b3da513e37f374d85e34cfea 100644
--- a/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/locale.messages.members/not_testable.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/locale.messages.members/not_testable.pass.cpp
@@ -28,6 +28,8 @@ public:
         : std::messages<CharT>(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/locale.messages.virtuals/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/locale.messages.virtuals/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/locale.messages.virtuals/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/locale.messages.virtuals/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/messages_base.pass.cpp b/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/messages_base.pass.cpp
index 7f2e4f9b9abddc61a9e06794e4ce37d626cd48d3..ce6d70be72884a12eb479d3eebe276787e4a056f 100644
--- a/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/messages_base.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/messages_base.pass.cpp
@@ -17,7 +17,9 @@
 #include <locale>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     std::messages_base mb;
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/types.pass.cpp b/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/types.pass.cpp
index 454d9b1824271b63c5d95ab2b170e1ea40723095..436290698cc15de91ad5cf4a5c1dc30d6d3914ab 100644
--- a/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/types.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/types.pass.cpp
@@ -20,7 +20,7 @@
 #include <locale>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::locale::facet, std::messages<char> >::value), "");
     static_assert((std::is_base_of<std::messages_base, std::messages<char> >::value), "");
@@ -30,4 +30,6 @@ int main()
     static_assert((std::is_same<std::messages<wchar_t>::char_type, wchar_t>::value), "");
     static_assert((std::is_same<std::messages<char>::string_type, std::string>::value), "");
     static_assert((std::is_same<std::messages<wchar_t>::string_type, std::wstring>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.messages/nothing_to_do.pass.cpp b/libcxx/test/std/localization/locale.categories/category.messages/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locale.categories/category.messages/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.messages/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/ctor.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/ctor.pass.cpp
index f70f8eeadd3a2d9569e1d0baff283fef3a6af514..360ff3ad61f5f0a97a60cfd8e88fa523cbf9817c 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/ctor.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/ctor.pass.cpp
@@ -31,7 +31,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet);
@@ -48,4 +48,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_en_US.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_en_US.pass.cpp
index 94f9bd7a9a636cf00225ec5c8f94f160b980c5c7..9fec21f51b96d4ace287a2e2801382b5450aa4a5 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_en_US.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_en_US.pass.cpp
@@ -43,7 +43,7 @@ public:
         : Fw(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::string loc_name(LOCALE_en_US_UTF_8);
@@ -719,4 +719,6 @@ int main()
             assert(err == std::ios_base::failbit);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_fr_FR.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_fr_FR.pass.cpp
index 27ae11eed5765982a1fbd1bd7588ab0c02bb2ccd..292f5eaea9269d55a72fcc267bf3c21427ac20d2 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_fr_FR.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_fr_FR.pass.cpp
@@ -76,7 +76,7 @@ static std::wstring convert_thousands_sep(std::wstring const& in) {
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::string loc_name(LOCALE_fr_FR_UTF_8);
@@ -753,4 +753,6 @@ int main()
             assert(ex == 123456789);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_ru_RU.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_ru_RU.pass.cpp
index b543799accbab5c76f9d7255fc462ca62c8128b2..c13849804fcdd5364d6b77b0c71dab86c4fd2ae3 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_ru_RU.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_ru_RU.pass.cpp
@@ -55,7 +55,7 @@ public:
         : Fw(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::string loc_name(LOCALE_ru_RU_UTF_8);
@@ -735,4 +735,6 @@ int main()
             assert(ex == -123456789);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_zh_CN.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_zh_CN.pass.cpp
index 20ba6f4914a124a8e37302116802637919be5176..9b006f55b7a28e8e558541a0496c42e9414c58d6 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_zh_CN.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_zh_CN.pass.cpp
@@ -49,7 +49,7 @@ public:
         : Fw(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::string loc_name(LOCALE_zh_CN_UTF_8);
@@ -725,4 +725,6 @@ int main()
             assert(err == std::ios_base::failbit);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_string_en_US.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_string_en_US.pass.cpp
index a5cb05334c4e102fef4f4e272a1be26312a36def..1b1a471e185c3e710e64d54f3b40f901b0cdef66 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_string_en_US.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_string_en_US.pass.cpp
@@ -43,7 +43,7 @@ public:
         : Fw(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::string loc_name(LOCALE_en_US_UTF_8);
@@ -727,4 +727,6 @@ int main()
             assert(ex == L"");
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.virtuals/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.virtuals/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.virtuals/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.virtuals/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/types.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/types.pass.cpp
index 9ad7528c2054b3e5df06336f1fd45e5c64df56d9..7bc04801efaa9343d95b8b3d7c30d56b028ef5df 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/types.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/types.pass.cpp
@@ -20,7 +20,7 @@
 #include <locale>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::locale::facet, std::money_get<char> >::value), "");
     static_assert((std::is_base_of<std::locale::facet, std::money_get<wchar_t> >::value), "");
@@ -30,4 +30,6 @@ int main()
     static_assert((std::is_same<std::money_get<wchar_t>::iter_type, std::istreambuf_iterator<wchar_t> >::value), "");
     static_assert((std::is_same<std::money_get<char>::string_type, std::string>::value), "");
     static_assert((std::is_same<std::money_get<wchar_t>::string_type, std::wstring>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/ctor.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/ctor.pass.cpp
index bdbb0b6cd6008a4db0521c490447bfafcd7c6aa5..309d26c5d74a9bb6cfcd6f9bb0f2d7bf67ff25a3 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/ctor.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/ctor.pass.cpp
@@ -31,7 +31,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet);
@@ -48,4 +48,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_en_US.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_en_US.pass.cpp
index 28f7451e9096dd4f177d8a9f14e632db2870c72a..d6e4d6cc1d9a821faabae53074ec868b44d70ef3 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_en_US.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_en_US.pass.cpp
@@ -43,7 +43,7 @@ public:
         : Fw(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::string loc_name(LOCALE_en_US_UTF_8);
@@ -490,4 +490,6 @@ int main()
         assert(ios.width() == 0);
     }
 }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_fr_FR.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_fr_FR.pass.cpp
index e9e916a3ce54cdf73118d2eced4c7f18e610157d..72f3f65706ffdce23b2a9a1c369050b0e4cca80a 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_fr_FR.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_fr_FR.pass.cpp
@@ -78,7 +78,7 @@ static std::wstring convert_thousands_sep(std::wstring const& in) {
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::string loc_name(LOCALE_fr_FR_UTF_8);
@@ -524,4 +524,6 @@ int main()
         assert(ios.width() == 0);
     }
 }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_ru_RU.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_ru_RU.pass.cpp
index 1894144db6270c09b8e4133f2d197b5dfb294892..36f97b1d8164b8a5f856fd4ba8b84e8d32ba7818 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_ru_RU.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_ru_RU.pass.cpp
@@ -55,7 +55,7 @@ public:
         : Fw(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::string loc_name(LOCALE_ru_RU_UTF_8);
@@ -501,4 +501,6 @@ int main()
         assert(ios.width() == 0);
     }
 }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_zh_CN.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_zh_CN.pass.cpp
index 0a3d478ec67d51af4747f2d57deb78423b72105d..a300ba84752386882f267500c80406f05ae63a2b 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_zh_CN.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_zh_CN.pass.cpp
@@ -49,7 +49,7 @@ public:
         : Fw(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::string loc_name(LOCALE_zh_CN_UTF_8);
@@ -495,4 +495,6 @@ int main()
         assert(ios.width() == 0);
     }
 }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_string_en_US.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_string_en_US.pass.cpp
index ab4a5c6034b7915276b7428856a5f91c956c97d8..cd1ff643f833175f8ed06a1c29cf7c2555002f35 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_string_en_US.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_string_en_US.pass.cpp
@@ -43,7 +43,7 @@ public:
         : Fw(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::string loc_name(LOCALE_en_US_UTF_8);
@@ -490,4 +490,6 @@ int main()
         assert(ios.width() == 0);
     }
 }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.virtuals/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.virtuals/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.virtuals/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.virtuals/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/types.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/types.pass.cpp
index 27c2ff5d6b3b75b1beedd97697f987422667c5a7..bd797313c85edde20bb2768f5c75eec3b5947fc3 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/types.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/types.pass.cpp
@@ -20,7 +20,7 @@
 #include <locale>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::locale::facet, std::money_put<char> >::value), "");
     static_assert((std::is_base_of<std::locale::facet, std::money_put<wchar_t> >::value), "");
@@ -30,4 +30,6 @@ int main()
     static_assert((std::is_same<std::money_put<wchar_t>::iter_type, std::ostreambuf_iterator<wchar_t> >::value), "");
     static_assert((std::is_same<std::money_put<char>::string_type, std::string>::value), "");
     static_assert((std::is_same<std::money_put<wchar_t>::string_type, std::wstring>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/curr_symbol.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/curr_symbol.pass.cpp
index f04ff4fb6142a7d7400e81c761ef5436ef12fedd..43a2fbc173d02f610c4a3f22e4fdf66577bec9b3 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/curr_symbol.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/curr_symbol.pass.cpp
@@ -75,7 +75,7 @@ static bool glibc_version_less_than(char const* version) {
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f("C", 1);
@@ -179,4 +179,6 @@ int main()
         Fwt f(LOCALE_zh_CN_UTF_8, 1);
         assert(f.curr_symbol() == L"CNY ");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/decimal_point.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/decimal_point.pass.cpp
index a64388ca5ce759d4699d169f13f02e92f58be417..bec52e6abc0dd652ea8e5832e0098baa69ed086b 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/decimal_point.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/decimal_point.pass.cpp
@@ -56,7 +56,7 @@ public:
         : std::moneypunct_byname<wchar_t, true>(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f("C", 1);
@@ -153,4 +153,6 @@ int main()
         Fwt f(LOCALE_zh_CN_UTF_8, 1);
         assert(f.decimal_point() == L'.');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/frac_digits.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/frac_digits.pass.cpp
index 9bbc76868a8b81b7cf1f916751505a0696a22877..07d78229a4fe1230601b57446e283c093dcd2e3f 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/frac_digits.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/frac_digits.pass.cpp
@@ -55,7 +55,7 @@ public:
         : std::moneypunct_byname<wchar_t, true>(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f("C", 1);
@@ -141,4 +141,6 @@ int main()
         Fwt f(LOCALE_zh_CN_UTF_8, 1);
         assert(f.frac_digits() == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/grouping.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/grouping.pass.cpp
index 7ff50db737f83029565161d08682f3fe13b806e3..2c2da48642e09af990d1059108792b758e03e64d 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/grouping.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/grouping.pass.cpp
@@ -60,7 +60,7 @@ public:
         : std::moneypunct_byname<wchar_t, true>(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     // Monetary grouping strings may be terminated with 0 or CHAR_MAX, defining
     // how the grouping is repeated.
@@ -149,4 +149,6 @@ int main()
         Fwt f(LOCALE_zh_CN_UTF_8, 1);
         assert(f.grouping() == "\3");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/neg_format.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/neg_format.pass.cpp
index 6cd00de657ce94f0ec5b25c046eef01639d666c1..f3f637b60df580a9c3e26d503f6ae0c0c7f9e063 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/neg_format.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/neg_format.pass.cpp
@@ -60,7 +60,7 @@ public:
         : std::moneypunct_byname<wchar_t, true>(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f("C", 1);
@@ -226,4 +226,6 @@ int main()
         assert(p.field[2] == std::money_base::none);
         assert(p.field[3] == std::money_base::value);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/negative_sign.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/negative_sign.pass.cpp
index 6857810bd0300710d3e90281938afbc2d9ac39d2..5567fc08eb541ef62e5b5d1755b0691d9d8b8e8e 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/negative_sign.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/negative_sign.pass.cpp
@@ -55,7 +55,7 @@ public:
         : std::moneypunct_byname<wchar_t, true>(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f("C", 1);
@@ -141,4 +141,6 @@ int main()
         Fwt f(LOCALE_zh_CN_UTF_8, 1);
         assert(f.negative_sign() == L"-");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/pos_format.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/pos_format.pass.cpp
index ff3cdcdb2fd1cb8b661f15d58493f9da5c76fd34..f7d396a662516c406f561c226021e2ba9218ab7e 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/pos_format.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/pos_format.pass.cpp
@@ -60,7 +60,7 @@ public:
         : std::moneypunct_byname<wchar_t, true>(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f("C", 1);
@@ -226,4 +226,6 @@ int main()
         assert(p.field[2] == std::money_base::none);
         assert(p.field[3] == std::money_base::value);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/positive_sign.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/positive_sign.pass.cpp
index 50a7ca939baa790a75a10b423695fe77ea94992e..43dfa2a2f183131762d1200bedb1a9a74145630b 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/positive_sign.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/positive_sign.pass.cpp
@@ -55,7 +55,7 @@ public:
         : std::moneypunct_byname<wchar_t, true>(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f("C", 1);
@@ -141,4 +141,6 @@ int main()
         Fwt f(LOCALE_zh_CN_UTF_8, 1);
         assert(f.positive_sign() == L"");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/thousands_sep.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/thousands_sep.pass.cpp
index e0bfd88a8bfd0649a25f8f88d5fc74d5157a400f..c789c4e5b1b1e5e4a58b46879c9881572eacd1c1 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/thousands_sep.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/thousands_sep.pass.cpp
@@ -59,7 +59,7 @@ public:
         : std::moneypunct_byname<wchar_t, true>(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f("C", 1);
@@ -170,4 +170,6 @@ int main()
         Fwt f(LOCALE_zh_CN_UTF_8, 1);
         assert(f.thousands_sep() == L',');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/ctor.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/ctor.pass.cpp
index 4717d4c0f1dccc23febe5cd38295fe68580f4d93..3b52f7afc742a33ed0d5aab1aa0538efb9f295b1 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/ctor.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/ctor.pass.cpp
@@ -31,7 +31,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet);
@@ -48,4 +48,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/curr_symbol.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/curr_symbol.pass.cpp
index 5773224258678ddb4c15b12b9364be9b60a53cb9..7b3b75a19c2131bf14ab4c09447abf80bf9e5f90 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/curr_symbol.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/curr_symbol.pass.cpp
@@ -53,7 +53,7 @@ public:
         : std::moneypunct<wchar_t, true>(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f(1);
@@ -71,4 +71,6 @@ int main()
         Fwt f(1);
         assert(f.curr_symbol() == std::wstring());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/decimal_point.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/decimal_point.pass.cpp
index 206f325354d55bc64e1d007487e166c938917331..34d02032cc9358753269abfb7d208a6517cd2479 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/decimal_point.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/decimal_point.pass.cpp
@@ -53,7 +53,7 @@ public:
         : std::moneypunct<wchar_t, true>(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f(1);
@@ -71,4 +71,6 @@ int main()
         Fwt f(1);
         assert(f.decimal_point() == std::numeric_limits<wchar_t>::max());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/frac_digits.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/frac_digits.pass.cpp
index b27ecd6df9f76100fb62d647665e272ca8f2246b..50365584d2453f0a71969a76b205cf3340a3fe19 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/frac_digits.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/frac_digits.pass.cpp
@@ -53,7 +53,7 @@ public:
         : std::moneypunct<wchar_t, true>(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f(1);
@@ -71,4 +71,6 @@ int main()
         Fwt f(1);
         assert(f.frac_digits() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/grouping.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/grouping.pass.cpp
index e959ad8abadf4dc70e35976060e1f26decb88a16..9e12e322044c5a82a37ad33030da14529f58873b 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/grouping.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/grouping.pass.cpp
@@ -53,7 +53,7 @@ public:
         : std::moneypunct<wchar_t, true>(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f(1);
@@ -71,4 +71,6 @@ int main()
         Fwt f(1);
         assert(f.grouping() == std::string());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/neg_format.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/neg_format.pass.cpp
index e9950b1a78ed8502de5e7690b7125fd59140bd16..cb511990959815ea404442ad6f514f850fbda294 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/neg_format.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/neg_format.pass.cpp
@@ -50,7 +50,7 @@ public:
         : std::moneypunct<wchar_t, true>(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f(1);
@@ -84,4 +84,6 @@ int main()
         assert(p.field[2] == std::money_base::none);
         assert(p.field[3] == std::money_base::value);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/negative_sign.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/negative_sign.pass.cpp
index 3ef5e84fc05ce3ed021020caf0438b409252922a..6f134e7847e5ba2178cfc0887849b66a4dcdbcb7 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/negative_sign.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/negative_sign.pass.cpp
@@ -54,7 +54,7 @@ public:
         : std::moneypunct<wchar_t, true>(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f(1);
@@ -72,4 +72,6 @@ int main()
         Fwt f(1);
         assert(f.negative_sign() == L"-");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/pos_format.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/pos_format.pass.cpp
index 3c3034bbe9ddff8697e79dbdc29257bbb568ddf7..bff44a69d88f280898ced4e20426ae375a60d3c8 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/pos_format.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/pos_format.pass.cpp
@@ -50,7 +50,7 @@ public:
         : std::moneypunct<wchar_t, true>(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f(1);
@@ -84,4 +84,6 @@ int main()
         assert(p.field[2] == std::money_base::none);
         assert(p.field[3] == std::money_base::value);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/positive_sign.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/positive_sign.pass.cpp
index dbe3e4ba786363fce27edbbf48b9b2583d45d991..8686e20051b25ce79132596a4ebd26be6c6c0469 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/positive_sign.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/positive_sign.pass.cpp
@@ -53,7 +53,7 @@ public:
         : std::moneypunct<wchar_t, true>(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f(1);
@@ -71,4 +71,6 @@ int main()
         Fwt f(1);
         assert(f.positive_sign() == std::wstring());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/thousands_sep.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/thousands_sep.pass.cpp
index 7b24c6dc9ed8b4fddeb765fb60f83000884736a6..42d28d09656cef3fbaa5efe4c988977df579c3f2 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/thousands_sep.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/thousands_sep.pass.cpp
@@ -53,7 +53,7 @@ public:
         : std::moneypunct<wchar_t, true>(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f(1);
@@ -71,4 +71,6 @@ int main()
         Fwt f(1);
         assert(f.thousands_sep() == std::numeric_limits<wchar_t>::max());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.virtuals/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.virtuals/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.virtuals/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.virtuals/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/money_base.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/money_base.pass.cpp
index d02c3b43e8adc38e2f9dd8e26846dd18e11df774..58f04905a0a661bfa8a46d160ac2de3200f3bacf 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/money_base.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/money_base.pass.cpp
@@ -18,7 +18,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::money_base mb; ((void)mb);
     static_assert(std::money_base::none == 0, "");
@@ -29,4 +29,6 @@ int main()
     static_assert(sizeof(std::money_base::pattern) == 4, "");
     std::money_base::pattern p;
     p.field[0] = std::money_base::none;
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/types.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/types.pass.cpp
index 439f8c31f732c192093488f4bd09b88573977ffb..24ddadfb3a7e4d39856b110fffe49e19f972f313 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/types.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/types.pass.cpp
@@ -29,7 +29,7 @@
 template <class T>
 void test(const T &) {}
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::locale::facet, std::moneypunct<char> >::value), "");
     static_assert((std::is_base_of<std::locale::facet, std::moneypunct<wchar_t> >::value), "");
@@ -44,4 +44,6 @@ int main()
     test(std::moneypunct<char, true>::intl);
     test(std::moneypunct<wchar_t, false>::intl);
     test(std::moneypunct<wchar_t, true>::intl);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/nothing_to_do.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/ctor.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/ctor.pass.cpp
index afb58d5e214c27561650df4cedf9b48d01c4ef3a..5a3af4b953659ef562db8515a77e3e46dfba8335 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/ctor.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/ctor.pass.cpp
@@ -31,7 +31,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet);
@@ -48,4 +48,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_bool.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_bool.pass.cpp
index 0c71a7354736ea7e4f73ceca3dc384cb9ce3fcd6..79aa68dde8b703541052000d30be1d1ae4ac2fcd 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_bool.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_bool.pass.cpp
@@ -39,7 +39,7 @@ protected:
     virtual string_type do_falsename() const {return "no";}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     {
@@ -96,4 +96,6 @@ int main()
             assert(ex == "yes");
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_double.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_double.pass.cpp
index 0d30bbf70964ddaa99ea642c52d23c0b35c3bcbf..062d5cfd404918e2d5d4b487dde4d3575e69d645 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_double.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_double.pass.cpp
@@ -17876,7 +17876,7 @@ void test8()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
@@ -17886,4 +17886,6 @@ int main()
     test6();
     test7();
     test8();
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_long.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_long.pass.cpp
index 5cf9bfa1f7adb299f838228f1bdccc7710c006fe..1aee8bdfe864a9f0b67b6d714531102763cc7e3e 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_long.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_long.pass.cpp
@@ -39,7 +39,7 @@ protected:
     virtual std::string do_grouping() const {return std::string("\1\2\3");}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     {
@@ -340,4 +340,6 @@ int main()
         assert(ex == "-***1_00_0");
         assert(ios.width() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_long_double.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_long_double.pass.cpp
index 5fcc0e4646bf392ee6898852de09445436b7f6a5..3e71a1dfbfb8bf529eadf3729bbabc6f26875ace 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_long_double.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_long_double.pass.cpp
@@ -26206,7 +26206,7 @@ void test12()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
@@ -26246,4 +26246,6 @@ int main()
     {
         long double v = std::nan(""); ((void)v);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_long_long.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_long_long.pass.cpp
index 18d96754be7873833b17b712a6f52542e30103db..a3c49d36ae6d40a84028b1f2cf1a4426d6e43790 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_long_long.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_long_long.pass.cpp
@@ -39,7 +39,7 @@ protected:
     virtual std::string do_grouping() const {return std::string("\1\2\3");}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     {
@@ -340,4 +340,6 @@ int main()
         assert(ex == "-***1_00_0");
         assert(ios.width() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_pointer.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_pointer.pass.cpp
index f4fdf762067f5102bd7a117935cbcbecf5e46802..d366c3842bf9157d3b7b0dfd4bc1cc65f158b13f 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_pointer.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_pointer.pass.cpp
@@ -28,7 +28,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     {
@@ -45,4 +45,6 @@ int main()
         assert(rc > 0);
         assert(ex == expected_str);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_unsigned_long.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_unsigned_long.pass.cpp
index 98aba106cc19d8607870ea4a8d779b121400fb1f..420d22fb02869ca01c9b894cf5fd4f7b27051b19 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_unsigned_long.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_unsigned_long.pass.cpp
@@ -39,7 +39,7 @@ protected:
     virtual std::string do_grouping() const {return std::string("\1\2\3");}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     {
@@ -343,4 +343,6 @@ int main()
                                                  : "18_446_744_073_709_550_61_6"));
         assert(ios.width() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_unsigned_long_long.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_unsigned_long_long.pass.cpp
index ccebb6ce1a49cac5710e0da8e2768a257227b6ba..1ad3065c074ba4ae294b700020cc10fbdf1ee181 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_unsigned_long_long.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_unsigned_long_long.pass.cpp
@@ -39,7 +39,7 @@ protected:
     virtual std::string do_grouping() const {return std::string("\1\2\3");}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     {
@@ -340,4 +340,6 @@ int main()
         assert(ex == "18_446_744_073_709_550_61_6");
         assert(ios.width() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.virtuals/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.virtuals/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.virtuals/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.virtuals/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/types.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/types.pass.cpp
index 19e8ceeb02584842661114963a32be5bae1eb4cf..6011c75c1fe69a3183482a5f813b86722cb5c1aa 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/types.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/types.pass.cpp
@@ -20,7 +20,7 @@
 #include <iterator>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::locale::facet, std::num_put<char> >::value), "");
     static_assert((std::is_base_of<std::locale::facet, std::num_put<wchar_t> >::value), "");
@@ -28,4 +28,6 @@ int main()
     static_assert((std::is_same<std::num_put<wchar_t>::char_type, wchar_t>::value), "");
     static_assert((std::is_same<std::num_put<char>::iter_type, std::ostreambuf_iterator<char> >::value), "");
     static_assert((std::is_same<std::num_put<wchar_t>::iter_type, std::ostreambuf_iterator<wchar_t> >::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/ctor.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/ctor.pass.cpp
index 2929fb05e1fbd2770105cda1949bd9c186ff012a..096939d08420ae8cd5aadd6f356f0856ac1608cd 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/ctor.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/ctor.pass.cpp
@@ -31,7 +31,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet);
@@ -48,4 +48,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_bool.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_bool.pass.cpp
index 8b4a33e84719ba035955666bfba0c1951148ceb5..b577d96b73c4ee52ee5d03c44f7179ac9668014f 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_bool.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_bool.pass.cpp
@@ -51,7 +51,7 @@ protected:
     virtual string_type do_falsename() const {return "ab";}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -226,4 +226,6 @@ int main()
         assert(err == ios.goodbit);
         assert(b == true);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_double.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_double.pass.cpp
index 7e896f705c0a24b766323f9a9294b5ab2665bb07..3980d488d9635efe6e241a01508677db26222f75 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_double.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_double.pass.cpp
@@ -48,7 +48,7 @@ protected:
     virtual std::string do_grouping() const {return std::string("\1\2\3");}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -278,4 +278,6 @@ int main()
         assert(err == ios.goodbit);
         assert(std::abs(v - 3.14159265358979e+10)/3.14159265358979e+10 < 1.e-8);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_float.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_float.pass.cpp
index aa7ffcb7809add87f9b0160f1cc24569d1d8f2c7..1ac313f7d7a37702c9f3698bff2bff033acc7621 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_float.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_float.pass.cpp
@@ -35,7 +35,7 @@ public:
 };
 
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -208,4 +208,6 @@ int main()
         assert(err == ios.goodbit);
         assert(v == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_long.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_long.pass.cpp
index 02f2ba6dcb153917dd9c309c94629ceefa9ffb21..13511728678fca6884952f777d210f927470578c 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_long.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_long.pass.cpp
@@ -41,7 +41,7 @@ protected:
     virtual std::string do_grouping() const {return std::string("\1\2\3");}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -517,4 +517,6 @@ int main()
         assert(err == ios.failbit);
         assert(v == std::numeric_limits<long>::max());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_long_double.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_long_double.pass.cpp
index 89fa436a909eada7977193a1141907fa110c4109..49e8ae750d9cd32a60b65ce9634fefc41ae28744 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_long_double.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_long_double.pass.cpp
@@ -35,7 +35,7 @@ public:
 };
 
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -267,4 +267,6 @@ int main()
         assert(err == ios.goodbit);
         assert(v == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_long_long.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_long_long.pass.cpp
index 9f8153c6b28901bbe281ba82af9757bfd4c9a0cf..c3a66a9836aa6be3adc07d6b3aeb3033fed00459 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_long_long.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_long_long.pass.cpp
@@ -40,7 +40,7 @@ protected:
     virtual std::string do_grouping() const {return std::string("\1\2\3");}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -102,4 +102,6 @@ int main()
         const long long expect = 0x8000000000000000LL;
         assert(v == expect);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_pointer.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_pointer.pass.cpp
index 2388dce5fb78923da5d423e89b2f487a7fdfd57d..23b6ad932d6acbc8aef97317e2505e5b6e8f829c 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_pointer.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_pointer.pass.cpp
@@ -29,7 +29,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -57,4 +57,6 @@ int main()
         assert(err == ios.goodbit);
         assert(p == (void*)0x73);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_int.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_int.pass.cpp
index 36aafc2f484d82b3983068468475c30c9bf3ac27..8a1ee3914f7d4cb309612c7ec534b7b698658dfb 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_int.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_int.pass.cpp
@@ -40,7 +40,7 @@ protected:
     virtual std::string do_grouping() const {return std::string("\1\2\3");}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -79,4 +79,6 @@ int main()
         assert(err == ios.goodbit);
         assert(v == 0xFFFFFFFF);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_long.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_long.pass.cpp
index 47b58b34eedacbf11ffeb924f9729985dc9e88de..e97c460c7e40370d03b001575d75a5174a928081 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_long.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_long.pass.cpp
@@ -40,7 +40,7 @@ protected:
     virtual std::string do_grouping() const {return std::string("\1\2\3");}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -79,4 +79,6 @@ int main()
         assert(err == ios.goodbit);
         assert(v == 0xFFFFFFFF);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_long_long.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_long_long.pass.cpp
index 3518c30a038963050a5801b5df752b89a8dc586f..a5d57df05cc7707ab54e00d5b6e5304427f91857 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_long_long.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_long_long.pass.cpp
@@ -40,7 +40,7 @@ protected:
     virtual std::string do_grouping() const {return std::string("\1\2\3");}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -79,4 +79,6 @@ int main()
         assert(err == ios.goodbit);
         assert(v == 0xFFFFFFFFFFFFFFFFULL);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_short.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_short.pass.cpp
index f83148a1d509817114da95e3eb6b4dcecb418f2f..261cac3725f7920f957fba56328a4712e7cc0549 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_short.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_short.pass.cpp
@@ -40,7 +40,7 @@ protected:
     virtual std::string do_grouping() const {return std::string("\1\2\3");}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -79,4 +79,6 @@ int main()
         assert(err == ios.goodbit);
         assert(v == 0xFFFF);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/test_min_max.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/test_min_max.pass.cpp
index 5c6de9709b22a045e278ef9c5dee1925be4ca8be..92cbeda61bbeba6079f11861d843dbc8d89b471e 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/test_min_max.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/test_min_max.pass.cpp
@@ -51,7 +51,7 @@ void check_limits()
     }
 }
 
-int main()
+int main(int, char**)
 {
     check_limits<short>();
     check_limits<unsigned short>();
@@ -61,4 +61,6 @@ int main()
     check_limits<unsigned long>();
     check_limits<long long>();
     check_limits<unsigned long long>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/test_neg_one.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/test_neg_one.pass.cpp
index 4faa4155e4879d657b792d5e69f23fd5ffa12bf0..07a22cb6e55c72611a3cc9582195354c4e567255 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/test_neg_one.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/test_neg_one.pass.cpp
@@ -148,7 +148,7 @@ void test_negate() {
     }
 }
 
-int main()
+int main(int, char**)
 {
     test_neg_one<long>();
     test_neg_one<long long>();
@@ -161,4 +161,6 @@ int main()
     test_negate<unsigned int>();
     test_negate<unsigned long>();
     test_negate<unsigned long long>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.virtuals/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.virtuals/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.virtuals/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.virtuals/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/types.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/types.pass.cpp
index ab8c00edeb68abc5546b7aa048df6a6d290cd71a..42f210d3958d6235d6dc136aeec1a8c685d6275e 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/types.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/types.pass.cpp
@@ -20,7 +20,7 @@
 #include <iterator>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::locale::facet, std::num_get<char> >::value), "");
     static_assert((std::is_base_of<std::locale::facet, std::num_get<wchar_t> >::value), "");
@@ -28,4 +28,6 @@ int main()
     static_assert((std::is_same<std::num_get<wchar_t>::char_type, wchar_t>::value), "");
     static_assert((std::is_same<std::num_get<char>::iter_type, std::istreambuf_iterator<char> >::value), "");
     static_assert((std::is_same<std::num_get<wchar_t>::iter_type, std::istreambuf_iterator<wchar_t> >::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/nothing_to_do.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/date_order.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/date_order.pass.cpp
index b779be50f475e1c65c740e74553f0eaeebf99094..30624ecc8912f4dea95a47dba199b10f1d7f4f37 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/date_order.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/date_order.pass.cpp
@@ -33,7 +33,7 @@ public:
         : F(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         const my_facet f(LOCALE_en_US_UTF_8, 1);
@@ -51,4 +51,6 @@ int main()
         const my_facet f(LOCALE_zh_CN_UTF_8, 1);
         assert(f.date_order() == std::time_base::ymd);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/date_order_wide.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/date_order_wide.pass.cpp
index 62ca19784883c53abae44745238b9cec85ee7b52..d62071b94e280785fc41c89e11d17f2d3401636f 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/date_order_wide.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/date_order_wide.pass.cpp
@@ -33,7 +33,7 @@ public:
         : F(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         const my_facet f(LOCALE_en_US_UTF_8, 1);
@@ -51,4 +51,6 @@ int main()
         const my_facet f(LOCALE_zh_CN_UTF_8, 1);
         assert(f.date_order() == std::time_base::ymd);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_date.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_date.pass.cpp
index 5c0a5ff59a2ec0616ada82ba155b91146eaf8bfb..e5b5913256d7d09221551747e99dc84e1a17747b 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_date.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_date.pass.cpp
@@ -44,7 +44,7 @@ public:
         : F(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::ios_base::iostate err;
@@ -98,4 +98,6 @@ int main()
         assert(t.tm_year == 109);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_date_wide.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_date_wide.pass.cpp
index 7dd82ed63ac1da1ea2259f83756d2918433502dd..5506e4cace8d033782e8a321f7046747f7879978 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_date_wide.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_date_wide.pass.cpp
@@ -44,7 +44,7 @@ public:
         : F(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::ios_base::iostate err;
@@ -97,4 +97,6 @@ int main()
         assert(t.tm_year == 109);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_monthname.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_monthname.pass.cpp
index 787d4a00e9f3d6639eea9fdc053a8d99652de56e..5311a8565080614c0fd199714a28e0be0194a492 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_monthname.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_monthname.pass.cpp
@@ -36,7 +36,7 @@ public:
         : F(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::ios_base::iostate err;
@@ -71,4 +71,6 @@ int main()
         assert(t.tm_mon == 5);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_monthname_wide.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_monthname_wide.pass.cpp
index a975bc96293b30f82faeba9900a3cb155de8dbdd..e45260a6690a3ee9d766ac6e2ade0b4f1480206d 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_monthname_wide.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_monthname_wide.pass.cpp
@@ -45,7 +45,7 @@ public:
         : F2(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::ios_base::iostate err;
@@ -80,4 +80,6 @@ int main()
         assert(t.tm_mon == 5);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_one.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_one.pass.cpp
index c63fab2aa74ce66cca0054ecbd96cf6efd0c8468..bda40c56d2746e8d97ff34a24720fc2f8193e91a 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_one.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_one.pass.cpp
@@ -42,7 +42,7 @@ public:
         : F(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::ios_base::iostate err;
@@ -167,4 +167,6 @@ int main()
         assert(t.tm_hour == 23);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_one_wide.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_one_wide.pass.cpp
index 6c8d86e12ace4a6770aff4c3b139216dccf9cd36..d8715f825d055eeea2d34f7919cd226cded12822 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_one_wide.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_one_wide.pass.cpp
@@ -42,7 +42,7 @@ public:
         : F(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::ios_base::iostate err;
@@ -169,4 +169,6 @@ int main()
         assert(t.tm_hour == 23);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_time.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_time.pass.cpp
index bdb61c66d817d836856878a86a250e2b8c411b32..a007415d03403699d7c1b007b1e1ad353f51a7a0 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_time.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_time.pass.cpp
@@ -37,7 +37,7 @@ public:
         : F(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::ios_base::iostate err;
@@ -90,4 +90,6 @@ int main()
         assert(t.tm_sec == 15);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_time_wide.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_time_wide.pass.cpp
index b0e8b1c39c51490055aec2c2bc162ddbb0e417ef..0e2481d6a84cfd3d3427ae98043aeca3e7ed5cf7 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_time_wide.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_time_wide.pass.cpp
@@ -37,7 +37,7 @@ public:
         : F(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::ios_base::iostate err;
@@ -90,4 +90,6 @@ int main()
         assert(t.tm_sec == 15);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_weekday.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_weekday.pass.cpp
index 342c87a48bf9aff564fc0120e4f44533f6dcf507..308b08529eac0768f8e440037767dbb2a3a952b1 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_weekday.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_weekday.pass.cpp
@@ -40,7 +40,7 @@ public:
         : F(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::ios_base::iostate err;
@@ -87,4 +87,6 @@ int main()
         assert(t.tm_wday == 1);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_weekday_wide.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_weekday_wide.pass.cpp
index c2566095f732c5ceaf33088156513f0f6df40d0f..c52462e37c2bffd123dcb069ad7947befd5dde0f 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_weekday_wide.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_weekday_wide.pass.cpp
@@ -40,7 +40,7 @@ public:
         : F(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::ios_base::iostate err;
@@ -85,4 +85,6 @@ int main()
         assert(t.tm_wday == 1);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_year.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_year.pass.cpp
index a53cd059b98b19f8a7ca1dd2261f7ee003313bf5..09df423719ab13cf9c3507d043eaa1db1a87538f 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_year.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_year.pass.cpp
@@ -36,7 +36,7 @@ public:
         : F(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::ios_base::iostate err;
@@ -81,4 +81,6 @@ int main()
         assert(t.tm_year == 109);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_year_wide.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_year_wide.pass.cpp
index 93ae51e5559d26ce625e58a092bd6be18f6fd592..78c35e969bdf6ea7132b4e33e88f12212c08af74 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_year_wide.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_year_wide.pass.cpp
@@ -36,7 +36,7 @@ public:
         : F(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::ios_base::iostate err;
@@ -81,4 +81,6 @@ int main()
         assert(t.tm_year == 109);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/ctor.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/ctor.pass.cpp
index a920c5cb903faaeba49ce504839586e6e3941076..6fb9899de7b091ea62c0df2fe406eaa9d971dd49 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/ctor.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/ctor.pass.cpp
@@ -31,7 +31,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet);
@@ -48,4 +48,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/date_order.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/date_order.pass.cpp
index e14d1c57f3709084100f139432c7adc97b194aaa..47b06e9df042d4a83f0a31a19f5905b69bb0552c 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/date_order.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/date_order.pass.cpp
@@ -26,8 +26,10 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     assert(f.date_order() == std::time_base::mdy);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_date.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_date.pass.cpp
index 3f95fd3b4cb93be0cde9e4a922ad871ed8ea353e..1a1dae754f01d9e7193961b67dcd1c532305d1c0 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_date.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_date.pass.cpp
@@ -30,7 +30,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -47,4 +47,6 @@ int main()
         assert(t.tm_year == 105);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_date_wide.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_date_wide.pass.cpp
index e7f19a5dad2651aefa8ecc9d919f0a0193e710a3..1fe184bea2fca183fd841be9a4218d4dad24ab6c 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_date_wide.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_date_wide.pass.cpp
@@ -30,7 +30,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -47,4 +47,6 @@ int main()
         assert(t.tm_year == 105);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_many.pass.cpp
index 22b2825c865377b81577f643d292779a8d36bb2a..2416f6275d7301ec94df0917cf0e87963267a603 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_many.pass.cpp
@@ -30,7 +30,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -64,4 +64,6 @@ int main()
         assert(t.tm_min == 27);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_monthname.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_monthname.pass.cpp
index e7b86c791064a81d7ce7e61189e16b1ca5fca425..8e61dcca876a1caba7e84b3e5acd7227c8e28972 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_monthname.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_monthname.pass.cpp
@@ -30,7 +30,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -261,4 +261,6 @@ int main()
         assert(t.tm_mon == 0);
         assert(err == std::ios_base::failbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_monthname_wide.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_monthname_wide.pass.cpp
index 78d32ece4f1f8721473508fe3066f47cf1eec5dc..a8eb4864ecb00c4ce25f9055bad33aa69890e1f6 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_monthname_wide.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_monthname_wide.pass.cpp
@@ -30,7 +30,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -261,4 +261,6 @@ int main()
         assert(t.tm_mon == 0);
         assert(err == std::ios_base::failbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_one.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_one.pass.cpp
index fb8b498081748effe22f76ba5492b14e22e6ba50..0c6d9085b57ae85d770dc757f390ba592b633b33 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_one.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_one.pass.cpp
@@ -29,7 +29,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -301,4 +301,6 @@ int main()
         assert(i.base() == in+sizeof(in)-1);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_time.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_time.pass.cpp
index c2523dc5d2e5224c1976383ca398521d5d26efc3..ca0227973dd11fb0dd6f5a61662fa8130a20e7c3 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_time.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_time.pass.cpp
@@ -30,7 +30,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -113,4 +113,6 @@ int main()
 //         assert(t.tm_sec == 0);
         assert(err == std::ios_base::failbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_time_wide.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_time_wide.pass.cpp
index f78359c918b7ea9ade14f774194fdedba2d0065b..98f2a8570ef59044d625b748019d8bfd60467eb4 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_time_wide.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_time_wide.pass.cpp
@@ -30,7 +30,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -113,4 +113,6 @@ int main()
 //         assert(t.tm_sec == 0);
         assert(err == std::ios_base::failbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_weekday.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_weekday.pass.cpp
index f972a63bf202fa18da76d6596f944b697862dd4e..16e853a49915c3ce6af59cd46ac4a4fcec8409c8 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_weekday.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_weekday.pass.cpp
@@ -30,7 +30,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -216,4 +216,6 @@ int main()
         assert(t.tm_wday == 6);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_weekday_wide.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_weekday_wide.pass.cpp
index 3e6e982bd8a1dfac67fcdbb29c76b452740e3d68..3b7b4e9d83ba64c810705334be22e81cf6139fe6 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_weekday_wide.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_weekday_wide.pass.cpp
@@ -30,7 +30,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -216,4 +216,6 @@ int main()
         assert(t.tm_wday == 6);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_year.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_year.pass.cpp
index 210112f8e303655d1df612a943cabc04e1aef4c8..8a0b840591442322f5c0d62f9519e93c04f8819f 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_year.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_year.pass.cpp
@@ -29,7 +29,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -134,4 +134,6 @@ int main()
         assert(t.tm_year == 1099);
         assert(err == std::ios_base::goodbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.virtuals/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.virtuals/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.virtuals/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.virtuals/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/time_base.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/time_base.pass.cpp
index c046a7de6ce5085f3f56b156605556e760ef4077..c1b509b40d53927647b516d5fb22a5f05d4a4e4b 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/time_base.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/time_base.pass.cpp
@@ -17,7 +17,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::time_base::dateorder d = std::time_base::no_order;
     ((void)d); // Prevent unused warning
@@ -26,4 +26,6 @@ int main()
     assert(std::time_base::mdy == 2);
     assert(std::time_base::ymd == 3);
     assert(std::time_base::ydm == 4);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/types.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/types.pass.cpp
index ba0dd69e45227ece8aabef52410efd7e27e3e855..bd74f7da8e6156843f5e7ab6a1e0805539773d56 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/types.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/types.pass.cpp
@@ -27,7 +27,7 @@
 #include <iterator>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::locale::facet, std::time_get<char> >::value), "");
     static_assert((std::is_base_of<std::locale::facet, std::time_get<wchar_t> >::value), "");
@@ -37,4 +37,6 @@ int main()
     static_assert((std::is_same<std::time_get<wchar_t>::char_type, wchar_t>::value), "");
     static_assert((std::is_same<std::time_get<char>::iter_type, std::istreambuf_iterator<char> >::value), "");
     static_assert((std::is_same<std::time_get<wchar_t>::iter_type, std::istreambuf_iterator<wchar_t> >::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.put.byname/put1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.put.byname/put1.pass.cpp
index 30f1eef6e8f7784fc9f2af4c7ac4d49d4aabdbb2..cd70133274ec26945aab6008670f6a18cdceb089 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.put.byname/put1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.put.byname/put1.pass.cpp
@@ -45,7 +45,7 @@ public:
         : F(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     char str[200];
     output_iterator<char*> iter;
@@ -77,4 +77,6 @@ int main()
         assert((ex == "Today is Samedi which is abbreviated Sam.")||
                (ex == "Today is samedi which is abbreviated sam." ));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/ctor.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/ctor.pass.cpp
index 2010ef4ffd8cc339484e1e5a795bba193b3c757d..9d0ec1ad7183eb3cecfda1711df9f7a4f5fd9ac1 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/ctor.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/ctor.pass.cpp
@@ -31,7 +31,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet);
@@ -48,4 +48,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/locale.time.put.members/put1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/locale.time.put.members/put1.pass.cpp
index 24971f48f7cd1dceb3567f757d58ffc90ff00fc4..94faa80f1eff3932405747581149edb6fdfe9435 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/locale.time.put.members/put1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/locale.time.put.members/put1.pass.cpp
@@ -27,7 +27,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     char str[200];
@@ -57,4 +57,6 @@ int main()
         std::string ex(str, iter.base());
         assert(ex == "The number of the month is 05.");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/locale.time.put.members/put2.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/locale.time.put.members/put2.pass.cpp
index 9bef3e787c461bfe2765ec69beb1f73697593fa4..a3b6cf5b25cd841d7f67f5adc5007240dff1e307 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/locale.time.put.members/put2.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/locale.time.put.members/put2.pass.cpp
@@ -27,7 +27,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     char str[200];
@@ -328,4 +328,6 @@ int main()
         std::string ex(str, iter.base());
         assert(ex == "%");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/locale.time.put.virtuals/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/locale.time.put.virtuals/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/locale.time.put.virtuals/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/locale.time.put.virtuals/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/types.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/types.pass.cpp
index c638624d0bb5782cbb46b14d9562f5237d8eb4cc..4361094f4b0c16970e2d6cf64d854cb813cc1a3e 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/types.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/types.pass.cpp
@@ -20,7 +20,7 @@
 #include <iterator>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::locale::facet, std::time_put<char> >::value), "");
     static_assert((std::is_base_of<std::locale::facet, std::time_put<wchar_t> >::value), "");
@@ -28,4 +28,6 @@ int main()
     static_assert((std::is_same<std::time_put<wchar_t>::char_type, wchar_t>::value), "");
     static_assert((std::is_same<std::time_put<char>::iter_type, std::ostreambuf_iterator<char> >::value), "");
     static_assert((std::is_same<std::time_put<wchar_t>::iter_type, std::ostreambuf_iterator<wchar_t> >::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/nothing_to_do.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/decimal_point.pass.cpp b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/decimal_point.pass.cpp
index cddc1497e9015a283d9621990d54089931249ba2..f8132872d4ca4442316aa6e1a6a64e9d73547927 100644
--- a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/decimal_point.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/decimal_point.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l("C");
@@ -61,4 +61,6 @@ int main()
             assert(np.decimal_point() == L',');
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/grouping.pass.cpp b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/grouping.pass.cpp
index c6e67dbfb27d13f990963e44f11958d3885a6359..4dbc7e7b8f2a9d0fd318b9c4cec0ea28c3c8eb54 100644
--- a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/grouping.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/grouping.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_macros.h"
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l("C");
@@ -70,4 +70,6 @@ int main()
             assert(np.grouping() == group);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/thousands_sep.pass.cpp b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/thousands_sep.pass.cpp
index 7d6978a9362198f1ff116adf4c134a8cd9d5dcf1..25690024027278104951524c903193c1b55c0e96 100644
--- a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/thousands_sep.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/thousands_sep.pass.cpp
@@ -26,7 +26,7 @@
 #include "test_macros.h"
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l("C");
@@ -84,4 +84,6 @@ int main()
             assert(np.thousands_sep() == wsep);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/ctor.pass.cpp b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/ctor.pass.cpp
index 39d0de2775fa9aea2b90ff4363cbdea42e57429a..e3a10a5c3a3d5d8885e28190f551b5354f58ec19 100644
--- a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/ctor.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/ctor.pass.cpp
@@ -30,7 +30,7 @@ public:
 
 template <class C> int my_facet<C>::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet<char>);
@@ -62,4 +62,6 @@ int main()
         assert(my_facet<wchar_t>::count == 1);
     }
     assert(my_facet<wchar_t>::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/decimal_point.pass.cpp b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/decimal_point.pass.cpp
index 43385c023e8d91348d2647e021c2048ae5b33d9e..5322c8a87f1a00dba86a2b9956c35265c4d65e54 100644
--- a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/decimal_point.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/decimal_point.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -28,4 +28,6 @@ int main()
         const std::numpunct<C>& np = std::use_facet<std::numpunct<C> >(l);
         assert(np.decimal_point() == L'.');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/falsename.pass.cpp b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/falsename.pass.cpp
index 7cbf9b43a0d3aa226d3f2090179b54b4a573cdac..d1f20f3bbdb89912170bdf22dcbd152ef907a069 100644
--- a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/falsename.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/falsename.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -28,4 +28,6 @@ int main()
         const std::numpunct<C>& np = std::use_facet<std::numpunct<C> >(l);
         assert(np.falsename() == std::wstring(L"false"));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/grouping.pass.cpp b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/grouping.pass.cpp
index 2ce956df73d98fd481a7881914b4501cb617250a..4c23c51acde3f2b8e4bf062c4fea70fe551519d5 100644
--- a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/grouping.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/grouping.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -28,4 +28,6 @@ int main()
         const std::numpunct<C>& np = std::use_facet<std::numpunct<C> >(l);
         assert(np.grouping() == std::string());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/thousands_sep.pass.cpp b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/thousands_sep.pass.cpp
index cc47edbf23c0d661a7072dce30fc665a12444596..2044c98a1df5be384b5decb04ba32f6793b52bd6 100644
--- a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/thousands_sep.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/thousands_sep.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -28,4 +28,6 @@ int main()
         const std::numpunct<C>& np = std::use_facet<std::numpunct<C> >(l);
         assert(np.thousands_sep() == L',');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/truename.pass.cpp b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/truename.pass.cpp
index 96fb3011d6327c821a0bc74ff133639221686fe2..359c96bef4ee40a63b9abfb061ad45c9ccf80973 100644
--- a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/truename.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/truename.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -28,4 +28,6 @@ int main()
         const std::numpunct<C>& np = std::use_facet<std::numpunct<C> >(l);
         assert(np.truename() == std::wstring(L"true"));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.virtuals/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.virtuals/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.virtuals/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.virtuals/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/types.pass.cpp b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/types.pass.cpp
index 236d9460d34d4f3d03471f135fa0c6edcf07aebc..212670af402a23b57c92ef9e8ffce1a2dadb4956 100644
--- a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/types.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/types.pass.cpp
@@ -21,7 +21,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -46,4 +46,6 @@ int main()
         static_assert((std::is_same<std::numpunct<wchar_t>::string_type, std::wstring>::value), "");
         static_assert((std::is_base_of<std::locale::facet, std::numpunct<wchar_t> >::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/facet.numpunct/nothing_to_do.pass.cpp b/libcxx/test/std/localization/locale.categories/facet.numpunct/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locale.categories/facet.numpunct/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/facet.numpunct/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/facets.examples/nothing_to_do.pass.cpp b/libcxx/test/std/localization/locale.categories/facets.examples/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locale.categories/facets.examples/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/facets.examples/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_mode.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_mode.pass.cpp
index 160594850d42a8e7db6b576ebd0beec61afd36a5..def721c4aac927c4d7a9f8560434e04587620730 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_mode.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_mode.pass.cpp
@@ -18,11 +18,13 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert(std::consume_header == 4);
     assert(std::generate_header == 2);
     assert(std::little_endian == 1);
     std::codecvt_mode e = std::consume_header;
     assert(e == 4);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16.pass.cpp
index 22be9593bd29c2391bb906a59bdb07f32b797764..a66129610fe426dfa838d712dd89efd4bc8d186d 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16.pass.cpp
@@ -24,7 +24,7 @@
 
 #include "count_new.hpp"
 
-int main()
+int main(int, char**)
 {
     assert(globalMemCounter.checkOutstandingNewEq(0));
     {
@@ -38,4 +38,6 @@ int main()
         assert(globalMemCounter.checkOutstandingNewNotEq(0));
     }
     assert(globalMemCounter.checkOutstandingNewEq(0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_always_noconv.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_always_noconv.pass.cpp
index 91d95af9a04d0540fbf3bae07364a3cabbccbddb..6bd37789d302486027bcce49ff1dbc8bfd7fde97 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_always_noconv.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_always_noconv.pass.cpp
@@ -21,7 +21,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf16<wchar_t> C;
@@ -41,4 +41,6 @@ int main()
         bool r = c.always_noconv();
         assert(r == false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_encoding.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_encoding.pass.cpp
index d3fbea6dc2ec8c7086ffde1e28b5bc30372844ec..2e8a1833c7897d11507b7cfa75a21f7572cc9360 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_encoding.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_encoding.pass.cpp
@@ -21,7 +21,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf16<wchar_t> C;
@@ -41,4 +41,6 @@ int main()
         int r = c.encoding();
         assert(r == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_in.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_in.pass.cpp
index e44783564c16f38a7619c2fd0f7f4b04d4ac6e7e..4ccf933d601caf5be37efc0d21a3e0248ccb4e57 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_in.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_in.pass.cpp
@@ -24,7 +24,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf16<char32_t> C;
@@ -735,4 +735,6 @@ int main()
         assert(np == n+2);
         assert(w == 0x56);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_length.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_length.pass.cpp
index 4e6fdf85849aba231440eb104a693c27ff257feb..39ecb8f0ea09529fcf3a356b015a3e38a6233ebc 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_length.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_length.pass.cpp
@@ -22,7 +22,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf16<wchar_t> C;
@@ -445,4 +445,6 @@ int main()
         r = c.length(m, n, n+2, 2);
         assert(r == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_max_length.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_max_length.pass.cpp
index 6422d56797b71ea668a37de98b715fdf2632758a..fa8c3269ad405a32bc8be3e7522e85d9bda2ef27 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_max_length.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_max_length.pass.cpp
@@ -21,7 +21,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf16<wchar_t> C;
@@ -59,4 +59,6 @@ int main()
         int r = c.max_length();
         assert(r == 6);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_out.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_out.pass.cpp
index afd1e6ad661ab2d32c8d5d00daa3907ecd356d9a..beabf842ec38a44b0578fe7d9f7fd8bf0b6125fc 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_out.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_out.pass.cpp
@@ -346,7 +346,9 @@ void TestHelper<CharT, 4>::test() {
   }
 }
 
-int main() {
+int main(int, char**) {
   TestHelper<char32_t>::test();
   TestHelper<wchar_t>::test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_unshift.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_unshift.pass.cpp
index 2471ccb195286a59eeda3dd97d0f9c01b529de55..2c37e25781568cc277b013fbc82776daa3ab0fc0 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_unshift.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_unshift.pass.cpp
@@ -23,7 +23,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf16<wchar_t> C;
@@ -52,4 +52,6 @@ int main()
         std::codecvt_base::result r = c.unshift(m, n, n+4, np);
         assert(r == std::codecvt_base::noconv);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8.pass.cpp
index f350b62ca6b5f86776b42fa5339e638a3f3b7da5..450f525092946081bf42f25c7ee46982b381b434 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8.pass.cpp
@@ -24,7 +24,7 @@
 
 #include "count_new.hpp"
 
-int main()
+int main(int, char**)
 {
     assert(globalMemCounter.checkOutstandingNewEq(0));
     {
@@ -38,4 +38,6 @@ int main()
         assert(globalMemCounter.checkOutstandingNewNotEq(0));
     }
     assert(globalMemCounter.checkOutstandingNewEq(0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_always_noconv.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_always_noconv.pass.cpp
index 167521573bdde4f502c0ff72dbb5fd5a65443449..7d7ba19be8d65451572a9be902303552c89a8981 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_always_noconv.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_always_noconv.pass.cpp
@@ -21,7 +21,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf8<wchar_t> C;
@@ -41,4 +41,6 @@ int main()
         bool r = c.always_noconv();
         assert(r == false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_encoding.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_encoding.pass.cpp
index 324546d9936f62fcaf4aaa4730ac6031145e1c8b..d8e689f62351bbdbb35f840032af285e13840dbe 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_encoding.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_encoding.pass.cpp
@@ -21,7 +21,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf8<wchar_t> C;
@@ -41,4 +41,6 @@ int main()
         int r = c.encoding();
         assert(r == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_in.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_in.pass.cpp
index 4f5d3d8fbee027536b5e5c421120ca9cb134e739..611d06305c941c2dbe9d1dc48aff7a995fc75239 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_in.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_in.pass.cpp
@@ -24,7 +24,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf8<char32_t> C;
@@ -356,4 +356,6 @@ int main()
         assert(np == n+1);
         assert(w == 0x56);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_length.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_length.pass.cpp
index 4b5e096afa9bcbf9039f4545ae1aea0e6db92dd4..2df1c96035c51fd4f1612d89a38b5d452c072221 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_length.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_length.pass.cpp
@@ -22,7 +22,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf8<wchar_t> C;
@@ -240,4 +240,6 @@ int main()
         r = c.length(m, n, n+1, 3);
         assert(r == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_max_length.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_max_length.pass.cpp
index a353ad6cf56ebff8557a1350e35d47187a832d15..57e5f5850c6e09a5edee3bae9f8396c84eb77494 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_max_length.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_max_length.pass.cpp
@@ -21,7 +21,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf8<wchar_t> C;
@@ -59,4 +59,6 @@ int main()
         int r = c.max_length();
         assert(r == 7);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_out.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_out.pass.cpp
index 430b5c2548c47d7dd24e6b4006117486ceed0668..f8b56bcb6cf6a9d13de5224f400bd5d80cb60141 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_out.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_out.pass.cpp
@@ -318,8 +318,10 @@ void TestHelper<CharT, 4>::test() {
   }
 }
 
-int main() {
+int main(int, char**) {
   TestHelper<wchar_t>::test();
   TestHelper<char32_t>::test();
   TestHelper<char16_t>::test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_unshift.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_unshift.pass.cpp
index 344b3e503ccb8f38bf535f7018be75655ffbf1b6..a41f997977f9aee806725a30f90ff94c6f1addb6 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_unshift.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_unshift.pass.cpp
@@ -23,7 +23,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf8<wchar_t> C;
@@ -52,4 +52,6 @@ int main()
         std::codecvt_base::result r = c.unshift(m, n, n+4, np);
         assert(r == std::codecvt_base::noconv);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_always_noconv.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_always_noconv.pass.cpp
index 6d658624e09030e840da021f406fb90a2bffa91c..c7fe09caf1306e78f0ec64ecc78f0e0171abeb4f 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_always_noconv.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_always_noconv.pass.cpp
@@ -21,7 +21,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf8_utf16<wchar_t> C;
@@ -41,4 +41,6 @@ int main()
         bool r = c.always_noconv();
         assert(r == false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_encoding.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_encoding.pass.cpp
index a392c8a25b65e04cb9e4baaf2d169a0491b1030a..595f7888e1ca6d6971240d1f1de58991331cb471 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_encoding.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_encoding.pass.cpp
@@ -21,7 +21,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf8_utf16<wchar_t> C;
@@ -41,4 +41,6 @@ int main()
         int r = c.encoding();
         assert(r == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_in.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_in.pass.cpp
index aab52fdf12ebead75bfc64404e37e2a1d6f2c697..482521032afd8f45b1e4d7833675885e463cf3e4 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_in.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_in.pass.cpp
@@ -234,10 +234,12 @@ void TestHelper<CharT, 4>::test() {
   }
 }
 
-int main() {
+int main(int, char**) {
 #ifndef _WIN32
   TestHelper<wchar_t>::test();
 #endif
   TestHelper<char32_t>::test();
   TestHelper<char16_t>::test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_length.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_length.pass.cpp
index 172a8734de654c68d26445bf1da9cddeb1cd8639..33a4b5f04bdaf51349c0685b861ef983e9619107 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_length.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_length.pass.cpp
@@ -22,7 +22,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf8_utf16<wchar_t> C;
@@ -231,4 +231,6 @@ int main()
         r = c.length(m, n, n+1, 2);
         assert(r == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_max_length.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_max_length.pass.cpp
index 247e0ce207a75f83469d88f2b86d078ef1f6f882..5d93d929e56866196c8c339ef1547d3873f32e6d 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_max_length.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_max_length.pass.cpp
@@ -21,7 +21,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf8_utf16<wchar_t> C;
@@ -59,4 +59,6 @@ int main()
         int r = c.max_length();
         assert(r == 7);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_out.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_out.pass.cpp
index 846df2156713b8be949178cc62424d5356676dc5..89908eb7756a86d6d4f9bdef485f9fc5800a6a86 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_out.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_out.pass.cpp
@@ -299,10 +299,12 @@ void TestHelper<CharT, 4>::test() {
   }
 }
 
-int main() {
+int main(int, char**) {
 #ifndef _WIN32
   TestHelper<wchar_t>::test();
 #endif
   TestHelper<char32_t>::test();
   TestHelper<char16_t>::test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_unshift.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_unshift.pass.cpp
index 96139bd5b6bb785e00be3118f3a39549dce34777..79b670055d557ae7e3876114bb7bab1abe3ea3fc 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_unshift.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_unshift.pass.cpp
@@ -23,7 +23,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf8_utf16<wchar_t> C;
@@ -52,4 +52,6 @@ int main()
         std::codecvt_base::result r = c.unshift(m, n, n+4, np);
         assert(r == std::codecvt_base::noconv);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.syn/nothing_to_do.pass.cpp b/libcxx/test/std/localization/locale.syn/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locale.syn/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/locale.syn/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/classification/isalnum.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/classification/isalnum.pass.cpp
index 68b9b9f1b73b148933226ef7dac13fb7293bef2f..2cf9e4b5749a7955aaf7f1d5193edb9a26ba0d89 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/classification/isalnum.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/classification/isalnum.pass.cpp
@@ -13,7 +13,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l;
     assert(!std::isalnum(' ', l));
@@ -27,4 +27,6 @@ int main()
     assert( std::isalnum('f', l));
     assert( std::isalnum('9', l));
     assert(!std::isalnum('+', l));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/classification/isalpha.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/classification/isalpha.pass.cpp
index 0e5a777b315f3b244db936cb4196ed36fbc0c97d..800c26cb918c25ad6ffc1acdb741e0f3e083acbb 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/classification/isalpha.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/classification/isalpha.pass.cpp
@@ -13,7 +13,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l;
     assert(!std::isalpha(' ', l));
@@ -27,4 +27,6 @@ int main()
     assert( std::isalpha('f', l));
     assert(!std::isalpha('9', l));
     assert(!std::isalpha('+', l));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/classification/iscntrl.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/classification/iscntrl.pass.cpp
index afca98b70b95454a10fa0bbf9ddc534842af2bc9..d5cd4a6b962586d9816e5a49abda2defbf239baa 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/classification/iscntrl.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/classification/iscntrl.pass.cpp
@@ -13,7 +13,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l;
     assert(!std::iscntrl(' ', l));
@@ -27,4 +27,6 @@ int main()
     assert(!std::iscntrl('f', l));
     assert(!std::iscntrl('9', l));
     assert(!std::iscntrl('+', l));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/classification/isdigit.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/classification/isdigit.pass.cpp
index 35a4540fdd89ee0d63ff44a6f3eb9498d7400baa..2e71bd394ac3b022e55c377279a61b62234ddd3c 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/classification/isdigit.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/classification/isdigit.pass.cpp
@@ -13,7 +13,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l;
     assert(!std::isdigit(' ', l));
@@ -27,4 +27,6 @@ int main()
     assert(!std::isdigit('f', l));
     assert( std::isdigit('9', l));
     assert(!std::isdigit('+', l));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/classification/isgraph.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/classification/isgraph.pass.cpp
index 3b4d0c55162a3730061ac37efcfa0eadd97ae129..406b7cbf97367361ce1d1a44081569f6ce8b3b56 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/classification/isgraph.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/classification/isgraph.pass.cpp
@@ -13,7 +13,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l;
     assert(!std::isgraph(' ', l));
@@ -27,4 +27,6 @@ int main()
     assert( std::isgraph('f', l));
     assert( std::isgraph('9', l));
     assert( std::isgraph('+', l));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/classification/islower.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/classification/islower.pass.cpp
index 057b7022608d53bcf889bc07876ec1d59e911580..2fc9ece026d2f2923c897f013b5f7581cf15b05f 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/classification/islower.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/classification/islower.pass.cpp
@@ -13,7 +13,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l;
     assert(!std::islower(' ', l));
@@ -27,4 +27,6 @@ int main()
     assert( std::islower('f', l));
     assert(!std::islower('9', l));
     assert(!std::islower('+', l));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/classification/isprint.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/classification/isprint.pass.cpp
index 990fc03eb826b177e5035c8bf7302aa5d3cee0e5..36fa16cbc7496acafc98f73ae093aefb54500ca6 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/classification/isprint.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/classification/isprint.pass.cpp
@@ -13,7 +13,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l;
     assert( std::isprint(' ', l));
@@ -27,4 +27,6 @@ int main()
     assert( std::isprint('f', l));
     assert( std::isprint('9', l));
     assert( std::isprint('+', l));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/classification/ispunct.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/classification/ispunct.pass.cpp
index b9fb94a3c4b18dfd03f9083619f16a7071387bcb..db11337805c0d6935d1e7086d2a7971768637947 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/classification/ispunct.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/classification/ispunct.pass.cpp
@@ -13,7 +13,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l;
     assert(!std::ispunct(' ', l));
@@ -27,4 +27,6 @@ int main()
     assert(!std::ispunct('f', l));
     assert(!std::ispunct('9', l));
     assert( std::ispunct('+', l));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/classification/isspace.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/classification/isspace.pass.cpp
index b00ba46e6308116d5f631b1dd6adf188f2487818..62e50d2fc25f5f3c1b381fc90fee47366224e509 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/classification/isspace.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/classification/isspace.pass.cpp
@@ -13,7 +13,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l;
     assert( std::isspace(' ', l));
@@ -27,4 +27,6 @@ int main()
     assert(!std::isspace('f', l));
     assert(!std::isspace('9', l));
     assert(!std::isspace('+', l));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/classification/isupper.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/classification/isupper.pass.cpp
index c5863beb30ec7388bb62ddee277549d8ba716d56..c986c7cdddc2c1789a698a61c4228b121ad366e6 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/classification/isupper.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/classification/isupper.pass.cpp
@@ -13,7 +13,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l;
     assert(!std::isupper(' ', l));
@@ -27,4 +27,6 @@ int main()
     assert(!std::isupper('f', l));
     assert(!std::isupper('9', l));
     assert(!std::isupper('+', l));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/classification/isxdigit.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/classification/isxdigit.pass.cpp
index 4a77628db94d4366f1bddf76802e507881c5c9c0..245f2ed6033cc3e67c9488e41f482dd127891a16 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/classification/isxdigit.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/classification/isxdigit.pass.cpp
@@ -13,7 +13,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l;
     assert(!std::isxdigit(' ', l));
@@ -27,4 +27,6 @@ int main()
     assert( std::isxdigit('f', l));
     assert( std::isxdigit('9', l));
     assert(!std::isxdigit('+', l));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/ctor.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/ctor.pass.cpp
index c16755e20ed36428a36585e5c5d82b7dcf6e239d..f28abb934e069f5a6458e4e56714ed294f168fe6 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/ctor.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/ctor.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_macros.h"
 #include "count_new.hpp"
 
-int main()
+int main(int, char**)
 {
     typedef std::wbuffer_convert<std::codecvt_utf8<wchar_t> > B;
 #if TEST_STD_VER > 11
@@ -55,4 +55,6 @@ int main()
         assert(globalMemCounter.checkOutstandingNewNotEq(0));
     }
     assert(globalMemCounter.checkOutstandingNewEq(0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/overflow.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/overflow.pass.cpp
index 66f95df53c7053e0e572039735cae3e4ece4c9f9..7c404288596b005717906eb61fc11f5ae20d7da2 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/overflow.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/overflow.pass.cpp
@@ -37,7 +37,7 @@ struct test_buf
     virtual int_type overflow(int_type c = traits_type::eof()) {return base::overflow(c);}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::ofstream bs("overflow.dat");
@@ -96,4 +96,6 @@ int main()
         assert(f.get() == -1);
     }
     std::remove("overflow.dat");
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/pbackfail.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/pbackfail.pass.cpp
index f268f9a2198f1862b8d64af5c25c3600939889ec..dc4144b159c761061d3bc2d6df78fddad6fef474 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/pbackfail.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/pbackfail.pass.cpp
@@ -37,7 +37,7 @@ struct test_buf
     virtual int_type pbackfail(int_type c = traits_type::eof()) {return base::pbackfail(c);}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::ifstream bs("underflow.dat");
@@ -55,4 +55,6 @@ int main()
         assert(f.sbumpc() == L'2');
         assert(f.sgetc() == L'3');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/rdbuf.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/rdbuf.pass.cpp
index ffd5a0df7abd338712c4921a194d030aa83df2b9..b58d1d8eb7bd4de282d7a393b809ea33a0303199 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/rdbuf.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/rdbuf.pass.cpp
@@ -17,7 +17,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::wbuffer_convert<std::codecvt_utf8<wchar_t> > B;
     {
@@ -27,4 +27,6 @@ int main()
         b.rdbuf(s.rdbuf());
         assert(b.rdbuf() == s.rdbuf());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/seekoff.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/seekoff.pass.cpp
index 4494d56c7c3287915d3e67a2920233a333326431..b50f10cc1714d07445fdfa9e8ce487f1a2b6892f 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/seekoff.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/seekoff.pass.cpp
@@ -31,7 +31,7 @@ public:
     ~test_codecvt() {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         wchar_t buf[10];
@@ -54,4 +54,6 @@ int main()
         assert(f.sgetc() == L'l');
     }
     std::remove("seekoff.dat");
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/state.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/state.pass.cpp
index 1816ad0c7751ad2293bb6c2763d7d2ec3a399ac7..0541dbfb93b43508010867bd03c65c574b0d2003 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/state.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/state.pass.cpp
@@ -17,7 +17,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::wbuffer_convert<std::codecvt_utf8<wchar_t> > B;
     {
@@ -25,4 +25,6 @@ int main()
         std::mbstate_t s = b.state();
         ((void)s);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/test.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/test.pass.cpp
index c22fb6a14a7afe655c44493e61834f7dd1a266b4..e309f3eb6501815de141383fecfb98a1c9fc2842 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/test.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/test.pass.cpp
@@ -15,7 +15,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::ofstream bytestream("myfile.txt");
@@ -32,4 +32,6 @@ int main()
         assert(ws == L"Hello");
     }
     std::remove("myfile.txt");
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/underflow.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/underflow.pass.cpp
index 523778f237f3fd00dfaead72d6f09e230a59be11..6d04935b30112c1fdaa866a1ab06cf0f5c853d16 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/underflow.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/underflow.pass.cpp
@@ -37,7 +37,7 @@ struct test_buf
     virtual int_type underflow() {return base::underflow();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::ifstream bs("underflow.dat");
@@ -80,4 +80,6 @@ int main()
         assert(f.sbumpc() == 0x4E53);
         assert(f.sbumpc() == test_buf::traits_type::eof());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.character/tolower.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.character/tolower.pass.cpp
index 72b939dfb5e819407a52d96101450f23a2dba957..9885dca53577ecf7214163e1f748cf44e2abec2a 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.character/tolower.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.character/tolower.pass.cpp
@@ -13,7 +13,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l;
     assert(std::tolower(' ', l) == ' ');
@@ -27,4 +27,6 @@ int main()
     assert(std::tolower('f', l) == 'f');
     assert(std::tolower('9', l) == '9');
     assert(std::tolower('+', l) == '+');
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.character/toupper.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.character/toupper.pass.cpp
index dbd936529efdd5e99192d6892b15f56612d12715..34f675b0592fcdbe5167d36acd4a7750d7db9e62 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.character/toupper.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.character/toupper.pass.cpp
@@ -13,7 +13,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l;
     assert(std::toupper(' ', l) == ' ');
@@ -27,4 +27,6 @@ int main()
     assert(std::toupper('f', l) == 'F');
     assert(std::toupper('9', l) == '9');
     assert(std::toupper('+', l) == '+');
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/converted.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/converted.pass.cpp
index b52bbc0bbcb66b3fbd7f16d925b841fff82955cc..802aaf65d0f8f68bd5469823438d5e7bfad34342 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/converted.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/converted.pass.cpp
@@ -61,4 +61,6 @@ void TestHelper<CharT, 4>::test() {
   }
 }
 
-int main() { TestHelper<wchar_t>::test(); }
+int main(int, char**) { TestHelper<wchar_t>::test(); 
+  return 0;
+}
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_codecvt.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_codecvt.pass.cpp
index 578547f8ec2180fccc02084fe5e249f160e2ab9b..3efd26fb4ce1c20e8e3226808d82ced330b6ab18 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_codecvt.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_codecvt.pass.cpp
@@ -18,7 +18,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf8<wchar_t> Codecvt;
@@ -36,4 +36,6 @@ int main()
         static_assert( std::is_constructible<Myconv, Codecvt*>::value, "");
 #endif
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_codecvt_state.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_codecvt_state.pass.cpp
index 0e58bc2252ec5eaa86b2968bf15a5a8c5eaf261c..6e2d5ff5e9c03d61ead719089f8f780aa87b6fc1 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_codecvt_state.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_codecvt_state.pass.cpp
@@ -16,7 +16,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf8<wchar_t> Codecvt;
@@ -24,4 +24,6 @@ int main()
         Myconv myconv(new Codecvt, std::mbstate_t());
         assert(myconv.converted() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_copy.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_copy.pass.cpp
index c1a874dc251a54f116ca173651fa91c7b879bbf5..d035c3160eb4de85cc7fb6b23f908fdf1d3c945c 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_copy.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_copy.pass.cpp
@@ -21,10 +21,12 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::codecvt_utf8<wchar_t> Codecvt;
     typedef std::wstring_convert<Codecvt> Myconv;
     static_assert(!std::is_copy_constructible<Myconv>::value, "");
     static_assert(!std::is_copy_assignable<Myconv>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_err_string.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_err_string.pass.cpp
index 364cfed80c7dd8e798383398213401dbdb605691..e284c13c0629e65bfc9cd8e95504e0a1b72bb6dd 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_err_string.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_err_string.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::codecvt_utf8<wchar_t> Codecvt;
     typedef std::wstring_convert<Codecvt> Myconv;
@@ -70,4 +70,6 @@ int main()
         std::wstring ws = myconv.from_bytes('\xA5');
         assert(ws == L"wide error");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/from_bytes.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/from_bytes.pass.cpp
index e527f31a1e2a8f5263f68d79da3bb8c5a565c933..c1a26d05582ce66622fd59c25a5ff8eb050eef87 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/from_bytes.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/from_bytes.pass.cpp
@@ -68,4 +68,6 @@ void TestHelper<CharT, 4>::test() {
   }
 }
 
-int main() { TestHelper<wchar_t>::test(); }
+int main(int, char**) { TestHelper<wchar_t>::test(); 
+  return 0;
+}
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/state.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/state.pass.cpp
index 0fb5b9f342f69be451351f2fddece96f55def61f..a7588dc252293b94d081867bbdbac16b91ff2aa7 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/state.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/state.pass.cpp
@@ -15,11 +15,13 @@
 #include <locale>
 #include <codecvt>
 
-int main()
+int main(int, char**)
 {
     typedef std::codecvt_utf8<wchar_t> Codecvt;
     typedef std::wstring_convert<Codecvt> Myconv;
     Myconv myconv;
     std::mbstate_t s = myconv.state();
     ((void)s);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/to_bytes.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/to_bytes.pass.cpp
index 2e4dce8bd72bb79c9ec0b0977e03c2d0b6637d79..397ba6494eeaacb112957475a289ba0b3a2d280a 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/to_bytes.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/to_bytes.pass.cpp
@@ -68,4 +68,6 @@ void TestHelper<CharT, 4>::test() {
   }
 }
 
-int main() { TestHelper<wchar_t>::test(); }
+int main(int, char**) { TestHelper<wchar_t>::test(); 
+  return 0;
+}
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/types.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/types.pass.cpp
index eb67ecffc11cd028df8564672b18345ebba52aaf..c2dea9a906717fc3b57fd6c852bf9ebd4212f2d4 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/types.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/types.pass.cpp
@@ -22,7 +22,7 @@
 #include <locale>
 #include <codecvt>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::wstring_convert<std::codecvt_utf8<wchar_t> > myconv;
@@ -31,4 +31,6 @@ int main()
         static_assert((std::is_same<myconv::state_type, std::mbstate_t>::value), "");
         static_assert((std::is_same<myconv::int_type, std::char_traits<wchar_t>::int_type>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/nothing_to_do.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/nothing_to_do.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.global.templates/has_facet.pass.cpp b/libcxx/test/std/localization/locales/locale.global.templates/has_facet.pass.cpp
index a895b1aa1072732864606da1cafebe9afe8d8e27..66539d1eabaf1c9f7c76ceeccb06e6ec5c1aa363 100644
--- a/libcxx/test/std/localization/locales/locale.global.templates/has_facet.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.global.templates/has_facet.pass.cpp
@@ -21,11 +21,13 @@ struct my_facet
 
 std::locale::id my_facet::id;
 
-int main()
+int main(int, char**)
 {
     std::locale loc;
     assert(std::has_facet<std::ctype<char> >(loc));
     assert(!std::has_facet<my_facet>(loc));
     std::locale loc2(loc, new my_facet);
     assert(std::has_facet<my_facet>(loc2));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.global.templates/use_facet.pass.cpp b/libcxx/test/std/localization/locales/locale.global.templates/use_facet.pass.cpp
index c7f53975d3ae1297720b3af958a9ae085251231f..3c2cb604232a99cf9a575143538c94ae6c8d9aed 100644
--- a/libcxx/test/std/localization/locales/locale.global.templates/use_facet.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.global.templates/use_facet.pass.cpp
@@ -30,7 +30,7 @@ struct my_facet
 
 std::locale::id my_facet::id;
 
-int main()
+int main(int, char**)
 {
 #ifndef TEST_HAS_NO_EXCEPTIONS
     try
@@ -53,4 +53,6 @@ int main()
         assert(facet_count == 1);
     }
     assert(facet_count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.cons/assign.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.cons/assign.pass.cpp
index 02b5f1096991cab1f4561158207a468eb1bb0f51..369fee4cb1985f5f418f62489230e8efedddf19d 100644
--- a/libcxx/test/std/localization/locales/locale/locale.cons/assign.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.cons/assign.pass.cpp
@@ -56,7 +56,7 @@ void check(const std::locale& loc)
     assert((std::has_facet<std::messages<wchar_t> >(loc)));
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::locale loc(LOCALE_ru_RU_UTF_8);
@@ -67,4 +67,6 @@ int main()
         check(loc2);
     }
     assert(globalMemCounter.checkOutstandingNewEq(0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.cons/char_pointer.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.cons/char_pointer.pass.cpp
index 5424a8b92dd5e565a24f35da49c30af2a9ec42d5..c324f394c8b6948abcb823827a67027f0f0c577f 100644
--- a/libcxx/test/std/localization/locales/locale/locale.cons/char_pointer.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.cons/char_pointer.pass.cpp
@@ -61,7 +61,7 @@ void check(const std::locale& loc)
     assert((std::has_facet<std::messages<wchar_t> >(loc)));
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::locale loc(LOCALE_ru_RU_UTF_8);
@@ -94,4 +94,6 @@ int main()
         std::locale ok("");
     }
     assert(globalMemCounter.checkOutstandingNewEq(0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.cons/copy.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.cons/copy.pass.cpp
index 885dfea37b7c0dee628327a43dc6c62e0e9eda87..4f96ab41554b9e3f9c4b5870cce16083607609ea 100644
--- a/libcxx/test/std/localization/locales/locale/locale.cons/copy.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.cons/copy.pass.cpp
@@ -54,7 +54,7 @@ void check(const std::locale& loc)
     assert((std::has_facet<std::messages<wchar_t> >(loc)));
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::locale loc(LOCALE_fr_FR_UTF_8);
@@ -64,4 +64,6 @@ int main()
         check(loc2);
     }
     assert(globalMemCounter.checkOutstandingNewEq(0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.cons/default.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.cons/default.pass.cpp
index 8f79b1842333e5950c51889522b80c291f9da76f..5c1e922cbfe9614e2e34537afac5ead0e0fbb1a5 100644
--- a/libcxx/test/std/localization/locales/locale/locale.cons/default.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.cons/default.pass.cpp
@@ -53,7 +53,7 @@ void check(const std::locale& loc)
     assert((std::has_facet<std::messages<wchar_t> >(loc)));
 }
 
-int main()
+int main(int, char**)
 {
     int ok;
     {
@@ -73,4 +73,6 @@ int main()
         assert(globalMemCounter.checkOutstandingNewEq(ok));
     }
     assert(globalMemCounter.checkOutstandingNewEq(ok));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.cons/locale_char_pointer_cat.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.cons/locale_char_pointer_cat.pass.cpp
index d0ccb8a340540e0c8f9cf3663ba3b656ade783d9..70f2cb92b797ebde749ee4cdf117abcfb23617d5 100644
--- a/libcxx/test/std/localization/locales/locale/locale.cons/locale_char_pointer_cat.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.cons/locale_char_pointer_cat.pass.cpp
@@ -59,7 +59,7 @@ void check(const std::locale& loc)
     assert((std::has_facet<std::messages<wchar_t> >(loc)));
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::locale loc(LOCALE_ru_RU_UTF_8);
@@ -68,4 +68,6 @@ int main()
         check(loc2);
     }
     assert(globalMemCounter.checkOutstandingNewEq(0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.cons/locale_facetptr.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.cons/locale_facetptr.pass.cpp
index 498682f283458e58918db4a45703d7a6a176eb9b..35c06ce50400f4a0f238674d14088429f3018350 100644
--- a/libcxx/test/std/localization/locales/locale/locale.cons/locale_facetptr.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.cons/locale_facetptr.pass.cpp
@@ -65,7 +65,7 @@ struct my_facet
 
 std::locale::id my_facet::id;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale loc(LOCALE_ru_RU_UTF_8);
@@ -85,4 +85,6 @@ int main()
         assert(loc == loc2);
     }
     assert(globalMemCounter.checkOutstandingNewEq(0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.cons/locale_locale_cat.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.cons/locale_locale_cat.pass.cpp
index 79db6f044ca2091ff8c0238a299f3536f1e80e4e..ba54e85542eddcac9414126be86babd54f2e65bc 100644
--- a/libcxx/test/std/localization/locales/locale/locale.cons/locale_locale_cat.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.cons/locale_locale_cat.pass.cpp
@@ -59,7 +59,7 @@ void check(const std::locale& loc)
     assert((std::has_facet<std::messages<wchar_t> >(loc)));
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::locale loc(LOCALE_ru_RU_UTF_8);
@@ -68,4 +68,6 @@ int main()
         check(loc2);
     }
     assert(globalMemCounter.checkOutstandingNewEq(0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.cons/locale_string_cat.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.cons/locale_string_cat.pass.cpp
index 5fdde6c67ff7994c513c873a18aae98f5724d7b5..3cb3aadac97c40a4088b090d8db5b7194fb3245a 100644
--- a/libcxx/test/std/localization/locales/locale/locale.cons/locale_string_cat.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.cons/locale_string_cat.pass.cpp
@@ -60,7 +60,7 @@ void check(const std::locale& loc)
     assert((std::has_facet<std::messages<wchar_t> >(loc)));
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::locale loc(LOCALE_ru_RU_UTF_8);
@@ -69,4 +69,6 @@ int main()
         check(loc2);
     }
     assert(globalMemCounter.checkOutstandingNewEq(0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.cons/string.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.cons/string.pass.cpp
index 449b9fbc2d1a030365a07c8e67738174e6f861a6..55b2f88c2bef2f1071100725ee4d62a57b7b4317 100644
--- a/libcxx/test/std/localization/locales/locale/locale.cons/string.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.cons/string.pass.cpp
@@ -55,7 +55,7 @@ void check(const std::locale& loc)
     assert((std::has_facet<std::messages<wchar_t> >(loc)));
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::locale loc(std::string(LOCALE_ru_RU_UTF_8));
@@ -69,4 +69,6 @@ int main()
         assert(loc != loc3);
     }
     assert(globalMemCounter.checkOutstandingNewEq(0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.members/combine.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.members/combine.pass.cpp
index 1a867fbfa6cc55cd8082704776a3dbcf67b3473b..fc1f3d33bef7125084879c614d58b05787339e19 100644
--- a/libcxx/test/std/localization/locales/locale/locale.members/combine.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.members/combine.pass.cpp
@@ -63,7 +63,7 @@ struct my_facet
 
 std::locale::id my_facet::id;
 
-int main()
+int main(int, char**)
 {
 {
     {
@@ -95,4 +95,6 @@ int main()
     assert(globalMemCounter.checkOutstandingNewEq(0));
 }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.members/name.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.members/name.pass.cpp
index 3a6e1b98c539bced3c86b70640d64f736918b05a..96ebdf39147ddf1bd2de79cceb479b200619a3dc 100644
--- a/libcxx/test/std/localization/locales/locale/locale.members/name.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.members/name.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale loc;
@@ -27,4 +27,6 @@ int main()
         std::locale loc(LOCALE_en_US_UTF_8);
         assert(loc.name() == LOCALE_en_US_UTF_8);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.operators/compare.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.operators/compare.pass.cpp
index b42e55ff67ccb5e31bcda8891b3fcf6584f3e0ff..ea083d1370dab3c51bf3f3f438c24d729210c555 100644
--- a/libcxx/test/std/localization/locales/locale/locale.operators/compare.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.operators/compare.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l;
@@ -30,4 +30,6 @@ int main()
             assert(l(s3, s2));
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.operators/eq.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.operators/eq.pass.cpp
index aeb877086156013723c8a79b39fc992b08dc6724..1efb487bc8dc3d51cc22b9bb935f3d911d8b2d8e 100644
--- a/libcxx/test/std/localization/locales/locale/locale.operators/eq.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.operators/eq.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     std::locale cloc;
     std::locale copy(cloc);
@@ -82,4 +82,6 @@ int main()
     assert(noname2 != noname1);
     assert(noname2 != nonamec);
     assert(noname2 == noname2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.statics/classic.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.statics/classic.pass.cpp
index 9060ae27d7a3170f2bafdd577b7f2da76bdf03c5..7594edcc2c633a8e5cbab8edfa766c400dd9a408 100644
--- a/libcxx/test/std/localization/locales/locale/locale.statics/classic.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.statics/classic.pass.cpp
@@ -48,11 +48,13 @@ void check(const std::locale& loc)
     assert((std::has_facet<std::messages<wchar_t> >(loc)));
 }
 
-int main()
+int main(int, char**)
 {
     std::locale loc = std::locale::classic();
     assert(loc.name() == "C");
     assert(loc == std::locale("C"));
     check(loc);
     check(std::locale("C"));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.statics/global.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.statics/global.pass.cpp
index 961bb2f4c47bbfbb93dcad260772b548e457be33..57f55aa1a76d69e35e3e3ee773964ad593faf78f 100644
--- a/libcxx/test/std/localization/locales/locale/locale.statics/global.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.statics/global.pass.cpp
@@ -52,7 +52,7 @@ void check(const std::locale& loc)
     assert((std::has_facet<std::messages<wchar_t> >(loc)));
 }
 
-int main()
+int main(int, char**)
 {
     std::locale loc;
     assert(loc.name() == "C");
@@ -61,4 +61,6 @@ int main()
     std::locale loc2;
     check(loc2);
     assert(loc2 == std::locale(LOCALE_en_US_UTF_8));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.types/locale.category/category.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.types/locale.category/category.pass.cpp
index 7724ffd00cee1f4870332d998b1362b0049bdf49..11c3de2975f3c22b58ba8eba879afc67228d283a 100644
--- a/libcxx/test/std/localization/locales/locale/locale.types/locale.category/category.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.types/locale.category/category.pass.cpp
@@ -23,7 +23,7 @@ template <class T>
 void test(const T &) {}
 
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::locale::category, int>::value), "");
     assert(std::locale::none == 0);
@@ -55,4 +55,6 @@ int main()
     test(std::locale::time);
     test(std::locale::messages);
     test(std::locale::all);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.types/locale.facet/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.types/locale.facet/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locales/locale/locale.types/locale.facet/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.types/locale.facet/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.types/locale.id/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.types/locale.id/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locales/locale/locale.types/locale.id/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.types/locale.id/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.types/nothing_to_do.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.types/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locales/locale/locale.types/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.types/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/nothing_to_do.pass.cpp b/libcxx/test/std/localization/locales/locale/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locales/locale/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/nothing_to_do.pass.cpp b/libcxx/test/std/localization/locales/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/locales/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/locales/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/localization.general/nothing_to_do.pass.cpp b/libcxx/test/std/localization/localization.general/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/localization/localization.general/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/localization.general/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/nothing_to_do.pass.cpp b/libcxx/test/std/nothing_to_do.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/std/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/nothing_to_do.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/c.math/cmath.pass.cpp b/libcxx/test/std/numerics/c.math/cmath.pass.cpp
index fa904864387891b32ea0bb604f591bfa953afb8c..3f9a5f557cc48e2df5e10435a07a7ebc074dc4f4 100644
--- a/libcxx/test/std/numerics/c.math/cmath.pass.cpp
+++ b/libcxx/test/std/numerics/c.math/cmath.pass.cpp
@@ -1514,7 +1514,7 @@ void test_trunc()
     assert(std::trunc(1) == 1);
 }
 
-int main()
+int main(int, char**)
 {
     test_abs();
     test_acos();
@@ -1586,4 +1586,6 @@ int main()
     test_scalbn();
     test_tgamma();
     test_trunc();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/c.math/ctgmath.pass.cpp b/libcxx/test/std/numerics/c.math/ctgmath.pass.cpp
index c2ea8e8755dc0c3e1c0ac439e9cdb4195e6ba39f..4cba6031aafb6c9d4bc1871e493d474cbbbf4f09 100644
--- a/libcxx/test/std/numerics/c.math/ctgmath.pass.cpp
+++ b/libcxx/test/std/numerics/c.math/ctgmath.pass.cpp
@@ -10,10 +10,12 @@
 
 #include <ctgmath>
 
-int main()
+int main(int, char**)
 {
     std::complex<double> cd;
     (void)cd;
     double x = std::sin(0);
     ((void)x); // Prevent unused warning
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/c.math/tgmath_h.pass.cpp b/libcxx/test/std/numerics/c.math/tgmath_h.pass.cpp
index c58827cb4af6d34cd418bb646fec711efff957d6..3fab28b0425d93a8657c97968e9ca7bc4d42e241 100644
--- a/libcxx/test/std/numerics/c.math/tgmath_h.pass.cpp
+++ b/libcxx/test/std/numerics/c.math/tgmath_h.pass.cpp
@@ -10,6 +10,8 @@
 
 #include <tgmath.h>
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/cfenv/cfenv.syn/cfenv.pass.cpp b/libcxx/test/std/numerics/cfenv/cfenv.syn/cfenv.pass.cpp
index 671e4d12d54a86f514251bc1e7e7ca42e2601a65..61378439298d2095896f6cc16e722c11c32cd3ac 100644
--- a/libcxx/test/std/numerics/cfenv/cfenv.syn/cfenv.pass.cpp
+++ b/libcxx/test/std/numerics/cfenv/cfenv.syn/cfenv.pass.cpp
@@ -57,7 +57,7 @@
 #error FE_DFL_ENV not defined
 #endif
 
-int main()
+int main(int, char**)
 {
     std::fenv_t fenv;
     std::fexcept_t fex;
@@ -74,4 +74,6 @@ int main()
     static_assert((std::is_same<decltype(std::feholdexcept(&fenv)), int>::value), "");
     static_assert((std::is_same<decltype(std::fesetenv(&fenv)), int>::value), "");
     static_assert((std::is_same<decltype(std::feupdateenv(&fenv)), int>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/ccmplx/ccomplex.pass.cpp b/libcxx/test/std/numerics/complex.number/ccmplx/ccomplex.pass.cpp
index 4be7122e775fe91ca737ab72e86ae8d8390e10ce..ad1f4c423ac680bb95c638fc036763b0209de3a7 100644
--- a/libcxx/test/std/numerics/complex.number/ccmplx/ccomplex.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/ccmplx/ccomplex.pass.cpp
@@ -10,8 +10,10 @@
 
 #include <ccomplex>
 
-int main()
+int main(int, char**)
 {
     std::complex<double> d;
     (void)d;
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/cmplx.over/UDT_is_rejected.fail.cpp b/libcxx/test/std/numerics/complex.number/cmplx.over/UDT_is_rejected.fail.cpp
index 0e9a7cefc55b088468215e02eebd0d68091d540f..bc0e5d8142fa8de33fb6bff3262c8a82ca205bae 100644
--- a/libcxx/test/std/numerics/complex.number/cmplx.over/UDT_is_rejected.fail.cpp
+++ b/libcxx/test/std/numerics/complex.number/cmplx.over/UDT_is_rejected.fail.cpp
@@ -26,7 +26,7 @@ UDT<long double> ldt;
 UDT<int> it;
 UDT<unsigned long> uit;
 
-int main()
+int main(int, char**)
 {
     {
         std::real(ft); // expected-error {{no matching function}}
@@ -70,4 +70,6 @@ int main()
         std::proj(it); // expected-error {{no matching function}}
         std::proj(uit); // expected-error {{no matching function}}
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/cmplx.over/arg.pass.cpp b/libcxx/test/std/numerics/complex.number/cmplx.over/arg.pass.cpp
index f05c42f25ef6508c28a9f210ee7d86f146eef47a..bbc865a5ad668355464b7084bc20998513fd5131 100644
--- a/libcxx/test/std/numerics/complex.number/cmplx.over/arg.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/cmplx.over/arg.pass.cpp
@@ -43,7 +43,7 @@ test()
     test<T>(10);
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
@@ -51,4 +51,6 @@ int main()
     test<int>();
     test<unsigned>();
     test<long long>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/cmplx.over/conj.pass.cpp b/libcxx/test/std/numerics/complex.number/cmplx.over/conj.pass.cpp
index 80bd15714410c4eaf42f7d9d191a951e5002e642..46bf69aade5afc3ad456e45b9bfda239b24b61e6 100644
--- a/libcxx/test/std/numerics/complex.number/cmplx.over/conj.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/cmplx.over/conj.pass.cpp
@@ -54,7 +54,7 @@ test()
     test<T>(10);
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
@@ -62,4 +62,6 @@ int main()
     test<int>();
     test<unsigned>();
     test<long long>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/cmplx.over/imag.pass.cpp b/libcxx/test/std/numerics/complex.number/cmplx.over/imag.pass.cpp
index 8be97fac2a47f96286890f2a2f6ed0b03e0048d5..a05781273630c0f54e2717ad0824c1dd5ad7127d 100644
--- a/libcxx/test/std/numerics/complex.number/cmplx.over/imag.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/cmplx.over/imag.pass.cpp
@@ -56,7 +56,7 @@ test()
     test<T, 10>();
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
@@ -64,4 +64,6 @@ int main()
     test<int>();
     test<unsigned>();
     test<long long>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/cmplx.over/norm.pass.cpp b/libcxx/test/std/numerics/complex.number/cmplx.over/norm.pass.cpp
index a3bf9dd27a7d64fbfbdacd90e0e4f41874b5dbaf..69a2eada84cd4614a6883e63b04647adf0ee3514 100644
--- a/libcxx/test/std/numerics/complex.number/cmplx.over/norm.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/cmplx.over/norm.pass.cpp
@@ -43,7 +43,7 @@ test()
     test<T>(10);
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
@@ -51,4 +51,6 @@ int main()
     test<int>();
     test<unsigned>();
     test<long long>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/cmplx.over/pow.pass.cpp b/libcxx/test/std/numerics/complex.number/cmplx.over/pow.pass.cpp
index 60a5b1957b500b89d1559e9924dbbe3800d9e335..802b9e7735a5b16265a02705d6b67742c4de47ad 100644
--- a/libcxx/test/std/numerics/complex.number/cmplx.over/pow.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/cmplx.over/pow.pass.cpp
@@ -78,7 +78,7 @@ test(typename std::enable_if<!std::is_integral<T>::value>::type* = 0, typename s
     test(std::complex<T>(3, 4), std::complex<U>(5, 6));
 }
 
-int main()
+int main(int, char**)
 {
     test<int, float>();
     test<int, double>();
@@ -100,4 +100,6 @@ int main()
 
     test<long double, float>();
     test<long double, double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/cmplx.over/proj.pass.cpp b/libcxx/test/std/numerics/complex.number/cmplx.over/proj.pass.cpp
index a9dfeae578789a0feaec2997a4e0b8a013c2d707..41b82b0d7b953d8d831d81d5a6f8df126bd83112 100644
--- a/libcxx/test/std/numerics/complex.number/cmplx.over/proj.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/cmplx.over/proj.pass.cpp
@@ -54,7 +54,7 @@ test()
     test<T>(10);
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
@@ -62,4 +62,6 @@ int main()
     test<int>();
     test<unsigned>();
     test<long long>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/cmplx.over/real.pass.cpp b/libcxx/test/std/numerics/complex.number/cmplx.over/real.pass.cpp
index 5d0fa76b30f482ffb7d99733b8c83ab0cd33d5cb..41e9c8fe2d6ba5446422ec76eae1f8485ac34086 100644
--- a/libcxx/test/std/numerics/complex.number/cmplx.over/real.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/cmplx.over/real.pass.cpp
@@ -56,7 +56,7 @@ test()
     test<T, 10>();
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
@@ -64,4 +64,6 @@ int main()
     test<int>();
     test<unsigned>();
     test<long long>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.literals/literals.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.literals/literals.pass.cpp
index ed944eb04aba4bdd4590a1a6fa583de577b30791..7d8d701fda6b898da83c740ae0b83a65703b639e 100644
--- a/libcxx/test/std/numerics/complex.number/complex.literals/literals.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.literals/literals.pass.cpp
@@ -15,7 +15,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using namespace std::literals::complex_literals;
 
@@ -47,4 +47,6 @@ int main()
     auto c2 = 3if;
     assert ( c1 == c2 );
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.literals/literals1.fail.cpp b/libcxx/test/std/numerics/complex.number/complex.literals/literals1.fail.cpp
index 0b09858a323f13a92d6b21472aaaeb89fb0b4706..c5e6b29101ce5b447c3944969834aa681c61719a 100644
--- a/libcxx/test/std/numerics/complex.number/complex.literals/literals1.fail.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.literals/literals1.fail.cpp
@@ -13,7 +13,9 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     std::complex<float> foo  = 1.0if;  // should fail w/conversion operator not found
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.literals/literals1.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.literals/literals1.pass.cpp
index 25d0d1d4412f1656c2c05fa829e2a6d3e17be454..ba9532a5ee321e6d30b243e155ea552d08223465 100644
--- a/libcxx/test/std/numerics/complex.number/complex.literals/literals1.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.literals/literals1.pass.cpp
@@ -13,7 +13,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     using namespace std::literals;
 
@@ -37,4 +37,6 @@ int main()
     auto c2 = 3if;
     assert ( c1 == c2 );
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.literals/literals2.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.literals/literals2.pass.cpp
index 9fbe5572aa6082d926ba23fe19e4ef4d655383bd..0b8d2f9cb3fd6cbde7817a4d0841c27984afe144 100644
--- a/libcxx/test/std/numerics/complex.number/complex.literals/literals2.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.literals/literals2.pass.cpp
@@ -13,7 +13,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     using namespace std;
 
@@ -37,4 +37,6 @@ int main()
     auto c2 = 3if;
     assert ( c1 == c2 );
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.member.ops/assignment_complex.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.member.ops/assignment_complex.pass.cpp
index 8ab5460a0be095002a46f219f9e40be6c21e0c6c..d0ccb14f156cd47d4fe37f60c053384fc7b72f08 100644
--- a/libcxx/test/std/numerics/complex.number/complex.member.ops/assignment_complex.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.member.ops/assignment_complex.pass.cpp
@@ -31,7 +31,7 @@ test()
     assert(c.imag() == -4.5);
 }
 
-int main()
+int main(int, char**)
 {
     test<float, float>();
     test<float, double>();
@@ -44,4 +44,6 @@ int main()
     test<long double, float>();
     test<long double, double>();
     test<long double, long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.member.ops/assignment_scalar.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.member.ops/assignment_scalar.pass.cpp
index cb9a778c27c68e84b23b4b00ac328f68aaa273b3..faab37ea4fdcf29477216daa2a280f24f430c101 100644
--- a/libcxx/test/std/numerics/complex.number/complex.member.ops/assignment_scalar.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.member.ops/assignment_scalar.pass.cpp
@@ -28,9 +28,11 @@ test()
     assert(c.imag() == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.member.ops/divide_equal_complex.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.member.ops/divide_equal_complex.pass.cpp
index b1d1288aefa5add3964db6039a53ed5937b3532c..052c2dceeca091102228ecf7c0462c66cfc72a8a 100644
--- a/libcxx/test/std/numerics/complex.number/complex.member.ops/divide_equal_complex.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.member.ops/divide_equal_complex.pass.cpp
@@ -44,9 +44,11 @@ test()
 
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.member.ops/divide_equal_scalar.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.member.ops/divide_equal_scalar.pass.cpp
index 511140c671e3022cf988b57cbfb6402713cb728a..63d34b0512eebd72a3a5195309d044dee9f260de 100644
--- a/libcxx/test/std/numerics/complex.number/complex.member.ops/divide_equal_scalar.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.member.ops/divide_equal_scalar.pass.cpp
@@ -35,9 +35,11 @@ test()
     assert(c.imag() == 4);
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.member.ops/minus_equal_complex.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.member.ops/minus_equal_complex.pass.cpp
index 11c5c319dbd7e249a8a35b3178f044a8d44a6b34..09cde61241bd6e4b3745990679dff9d4552e1891 100644
--- a/libcxx/test/std/numerics/complex.number/complex.member.ops/minus_equal_complex.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.member.ops/minus_equal_complex.pass.cpp
@@ -43,9 +43,11 @@ test()
     assert(c3.imag() == -6);
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.member.ops/minus_equal_scalar.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.member.ops/minus_equal_scalar.pass.cpp
index e3d9da7b50a070fb5c4aea021defdbff2c2f8672..ae5b07157def4f97754e1465147e38394832fa4c 100644
--- a/libcxx/test/std/numerics/complex.number/complex.member.ops/minus_equal_scalar.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.member.ops/minus_equal_scalar.pass.cpp
@@ -31,9 +31,11 @@ test()
     assert(c.imag() == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.member.ops/plus_equal_complex.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.member.ops/plus_equal_complex.pass.cpp
index d108b8a54ef8212937f1c1a1c1c8e88f9f90af9f..0c86b6750d31b4d818c182d3c112b9123959701d 100644
--- a/libcxx/test/std/numerics/complex.number/complex.member.ops/plus_equal_complex.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.member.ops/plus_equal_complex.pass.cpp
@@ -43,9 +43,11 @@ test()
     assert(c3.imag() == 6);
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.member.ops/plus_equal_scalar.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.member.ops/plus_equal_scalar.pass.cpp
index b417505fa08e6c067aa9ab628b20593f845a3054..498724a36270f1435eed97977d3bd500f781b30c 100644
--- a/libcxx/test/std/numerics/complex.number/complex.member.ops/plus_equal_scalar.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.member.ops/plus_equal_scalar.pass.cpp
@@ -31,9 +31,11 @@ test()
     assert(c.imag() == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.member.ops/times_equal_complex.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.member.ops/times_equal_complex.pass.cpp
index 1d04690859738f2035a6fbc84c4f8940fd287887..fc690072bfa1796fe28768d98acea0dce4c8269c 100644
--- a/libcxx/test/std/numerics/complex.number/complex.member.ops/times_equal_complex.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.member.ops/times_equal_complex.pass.cpp
@@ -43,9 +43,11 @@ test()
     assert(c3.imag() ==   3.5);
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.member.ops/times_equal_scalar.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.member.ops/times_equal_scalar.pass.cpp
index f32b247c2c61b21fbb1a1d085a443b6d8d869edb..6cb95ea660a26492f11b05d0a4aae08779f8bdfe 100644
--- a/libcxx/test/std/numerics/complex.number/complex.member.ops/times_equal_scalar.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.member.ops/times_equal_scalar.pass.cpp
@@ -35,9 +35,11 @@ test()
     assert(c.imag() == 3);
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.members/construct.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.members/construct.pass.cpp
index 75d9b5d672fdf9009e85cb2afc5da2bef4e0e237..fa5e5729f4008967c2df7e3b2438735e730bdddc 100644
--- a/libcxx/test/std/numerics/complex.number/complex.members/construct.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.members/construct.pass.cpp
@@ -63,9 +63,11 @@ test()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.members/real_imag.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.members/real_imag.pass.cpp
index b1b378b5687cd560edc7f861545025f3d1729051..c4a1ef93539826cc959388fc81b8147367b43bfe 100644
--- a/libcxx/test/std/numerics/complex.number/complex.members/real_imag.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.members/real_imag.pass.cpp
@@ -56,10 +56,12 @@ test()
     test_constexpr<T> ();
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
     test_constexpr<int> ();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.ops/complex_divide_complex.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.ops/complex_divide_complex.pass.cpp
index 44837cc09f59fa3334d520e95c939876d85cb017..5166fa57ff14d2fcced159613e06849066e0f903 100644
--- a/libcxx/test/std/numerics/complex.number/complex.ops/complex_divide_complex.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.ops/complex_divide_complex.pass.cpp
@@ -149,10 +149,12 @@ void test_edges()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
     test_edges();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.ops/complex_divide_scalar.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.ops/complex_divide_scalar.pass.cpp
index ec9af0d2131d6361417f3c15894f74243f12fe24..e7a1d81cf626173d95290e2c122fdcd1019dfa19 100644
--- a/libcxx/test/std/numerics/complex.number/complex.ops/complex_divide_scalar.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.ops/complex_divide_scalar.pass.cpp
@@ -32,9 +32,11 @@ test()
     test(lhs, rhs, x);
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.ops/complex_equals_complex.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.ops/complex_equals_complex.pass.cpp
index 88cee31584ab42f4482b3a59f654540a287e5788..27621f165cf8ad00c9ecd0775fef60d23ab4f881 100644
--- a/libcxx/test/std/numerics/complex.number/complex.ops/complex_equals_complex.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.ops/complex_equals_complex.pass.cpp
@@ -52,10 +52,12 @@ test()
     test_constexpr<T> ();
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
 //    test_constexpr<int> ();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.ops/complex_equals_scalar.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.ops/complex_equals_scalar.pass.cpp
index e08d85fd1eb5b39b6642974bd1c03c06ad81e997..1ec74e703f11743d1c6ec188466c2ae3805f6089 100644
--- a/libcxx/test/std/numerics/complex.number/complex.ops/complex_equals_scalar.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.ops/complex_equals_scalar.pass.cpp
@@ -73,10 +73,12 @@ test()
     test_constexpr<T> ();
     }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
 //     test_constexpr<int> ();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.ops/complex_minus_complex.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.ops/complex_minus_complex.pass.cpp
index eb93cbe63eecef55ab399c3547b19c94fa20adc0..999a2c91dc0e7fefc30cf572ecc276624a0e2b81 100644
--- a/libcxx/test/std/numerics/complex.number/complex.ops/complex_minus_complex.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.ops/complex_minus_complex.pass.cpp
@@ -40,9 +40,11 @@ test()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.ops/complex_minus_scalar.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.ops/complex_minus_scalar.pass.cpp
index 0b81ed949cb49f6728eec87bbd6621cc93a7226f..9aea6819c732ac45db377117b4a191010c1b26a7 100644
--- a/libcxx/test/std/numerics/complex.number/complex.ops/complex_minus_scalar.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.ops/complex_minus_scalar.pass.cpp
@@ -40,9 +40,11 @@ test()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.ops/complex_not_equals_complex.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.ops/complex_not_equals_complex.pass.cpp
index 4ad67be2cc07dafad844e0cc3ef16d2c6496804e..319e453a900a47111f7bd54649496d0fe42d1c4e 100644
--- a/libcxx/test/std/numerics/complex.number/complex.ops/complex_not_equals_complex.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.ops/complex_not_equals_complex.pass.cpp
@@ -54,10 +54,12 @@ test()
     test_constexpr<T> ();
     }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
 //   test_constexpr<int> ();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.ops/complex_not_equals_scalar.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.ops/complex_not_equals_scalar.pass.cpp
index 43f0f8c5d8f0cace1bfb42611c705a5e40280dc0..69c71cde0434c8584bfa006f17dafaa19d746a38 100644
--- a/libcxx/test/std/numerics/complex.number/complex.ops/complex_not_equals_scalar.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.ops/complex_not_equals_scalar.pass.cpp
@@ -73,10 +73,12 @@ test()
     test_constexpr<T> ();
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
 //     test_constexpr<int> ();
-    }
+    
+  return 0;
+}
diff --git a/libcxx/test/std/numerics/complex.number/complex.ops/complex_plus_complex.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.ops/complex_plus_complex.pass.cpp
index 46953f662d0c4174e75b39bc004256b2ec02b930..5a2fdcfb0da67e82a132f55d016665c8c22eb0b8 100644
--- a/libcxx/test/std/numerics/complex.number/complex.ops/complex_plus_complex.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.ops/complex_plus_complex.pass.cpp
@@ -40,9 +40,11 @@ test()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.ops/complex_plus_scalar.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.ops/complex_plus_scalar.pass.cpp
index 7f4a7a2b59c76c0d11e8e6e157a2518201bccb52..4f9dfb1d4166722ee9f6d63e2246c21f87080ed7 100644
--- a/libcxx/test/std/numerics/complex.number/complex.ops/complex_plus_scalar.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.ops/complex_plus_scalar.pass.cpp
@@ -40,9 +40,11 @@ test()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.ops/complex_times_complex.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.ops/complex_times_complex.pass.cpp
index ba499e51bb2962c9f2a6ed38b743c2a9d8a81c6a..f2203d4db93df8e91a79da16722497f4d14f8d38 100644
--- a/libcxx/test/std/numerics/complex.number/complex.ops/complex_times_complex.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.ops/complex_times_complex.pass.cpp
@@ -151,10 +151,12 @@ void test_edges()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
     test_edges();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.ops/complex_times_scalar.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.ops/complex_times_scalar.pass.cpp
index 94afd4b863fef47645a0ca753ab1f18e527c34a2..9fface6b75f7b7b2121542fc282ba2d974a4dd4e 100644
--- a/libcxx/test/std/numerics/complex.number/complex.ops/complex_times_scalar.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.ops/complex_times_scalar.pass.cpp
@@ -32,9 +32,11 @@ test()
     test(lhs, rhs, x);
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.ops/scalar_divide_complex.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.ops/scalar_divide_complex.pass.cpp
index e793c7dc95f065e2c0fc2de0ff6820af09b38db1..01b706dd7b2abc1ce8b40d08f7ff7aa536e97b03 100644
--- a/libcxx/test/std/numerics/complex.number/complex.ops/scalar_divide_complex.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.ops/scalar_divide_complex.pass.cpp
@@ -32,9 +32,11 @@ test()
     test(lhs, rhs, x);
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.ops/scalar_equals_complex.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.ops/scalar_equals_complex.pass.cpp
index 551fd2574a60c83d228975d3c080ac23fa8a2f88..d5dcc29182de08c1a073962a19071ce3854062a5 100644
--- a/libcxx/test/std/numerics/complex.number/complex.ops/scalar_equals_complex.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.ops/scalar_equals_complex.pass.cpp
@@ -73,10 +73,12 @@ test()
     test_constexpr<T> ();
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
 //     test_constexpr<int>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.ops/scalar_minus_complex.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.ops/scalar_minus_complex.pass.cpp
index b693898272e8e1e611c352b2ef8d4b53dab3940b..006572492731eb7810e3b54c4707f9ab1ba42aa1 100644
--- a/libcxx/test/std/numerics/complex.number/complex.ops/scalar_minus_complex.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.ops/scalar_minus_complex.pass.cpp
@@ -40,9 +40,11 @@ test()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.ops/scalar_not_equals_complex.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.ops/scalar_not_equals_complex.pass.cpp
index 3521814769b14fe7d6925694a96226a59776763c..edff47a016069eeb6d59ce25f007f836d41fa210 100644
--- a/libcxx/test/std/numerics/complex.number/complex.ops/scalar_not_equals_complex.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.ops/scalar_not_equals_complex.pass.cpp
@@ -73,10 +73,12 @@ test()
     test_constexpr<T> ();
     }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
 //     test_constexpr<int>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.ops/scalar_plus_complex.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.ops/scalar_plus_complex.pass.cpp
index 52ae2a150799b07a572955988dce91b7fd56cbd2..d8fc8a6d95841336980421d80ae26b9ea6192b01 100644
--- a/libcxx/test/std/numerics/complex.number/complex.ops/scalar_plus_complex.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.ops/scalar_plus_complex.pass.cpp
@@ -40,9 +40,11 @@ test()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.ops/scalar_times_complex.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.ops/scalar_times_complex.pass.cpp
index 1e96a3d9c3030f176892c7a33386ae7ca4f2a80b..a33347db06a273e1b36c94e359d875d16e9669c8 100644
--- a/libcxx/test/std/numerics/complex.number/complex.ops/scalar_times_complex.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.ops/scalar_times_complex.pass.cpp
@@ -32,9 +32,11 @@ test()
     test(lhs, rhs, x);
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.ops/stream_input.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.ops/stream_input.pass.cpp
index e6d944f42bb23136341d603d379fb496d2e5ed03..4f33b97ebc8fc3bcb05ff74516f779220c22592b 100644
--- a/libcxx/test/std/numerics/complex.number/complex.ops/stream_input.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.ops/stream_input.pass.cpp
@@ -16,7 +16,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::istringstream is("5");
@@ -95,4 +95,6 @@ int main()
         assert(c == std::complex<double>(-5.5, -6.5));
         assert(!is.eof());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.ops/stream_output.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.ops/stream_output.pass.cpp
index 2e72bd8a5e19259cce18b50471713c6d2394b2b2..2f1fa91e8dcd0d24d53f8c435dd3e48dde6cfa94 100644
--- a/libcxx/test/std/numerics/complex.number/complex.ops/stream_output.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.ops/stream_output.pass.cpp
@@ -16,10 +16,12 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::complex<double> c(1, 2);
     std::ostringstream os;
     os << c;
     assert(os.str() == "(1,2)");
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.ops/unary_minus.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.ops/unary_minus.pass.cpp
index c61c8779ff1f17c1572e810118377fcc55a94017..0249240e830e9ac27b070b44c711572f8e373b7a 100644
--- a/libcxx/test/std/numerics/complex.number/complex.ops/unary_minus.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.ops/unary_minus.pass.cpp
@@ -27,9 +27,11 @@ test()
     assert(c.imag() == -2.5);
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.ops/unary_plus.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.ops/unary_plus.pass.cpp
index e6d2de6e45d293ad87990b4d47af557558bc34f2..c5c2b6de12dfb1e64bf1f36be1bfbbe7155056d1 100644
--- a/libcxx/test/std/numerics/complex.number/complex.ops/unary_plus.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.ops/unary_plus.pass.cpp
@@ -27,9 +27,11 @@ test()
     assert(c.imag() == 2.5);
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.special/double_float_explicit.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.special/double_float_explicit.pass.cpp
index 9681bdb1766fe58b68df13cfe6fb8b1fe389390b..f2e64466fbdc8e29f724804f1c7aa2601e61f103 100644
--- a/libcxx/test/std/numerics/complex.number/complex.special/double_float_explicit.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.special/double_float_explicit.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     const std::complex<float> cd(2.5, 3.5);
@@ -35,4 +35,6 @@ int main()
     static_assert(cf.imag() == cd.imag(), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.special/double_float_implicit.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.special/double_float_implicit.pass.cpp
index db4fb2c4fc8576eb20b6f26afbb54706c3c4f587..72a4f0241455b54b3405cee429e59464bafb62c0 100644
--- a/libcxx/test/std/numerics/complex.number/complex.special/double_float_implicit.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.special/double_float_implicit.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     const std::complex<float> cd(2.5, 3.5);
@@ -35,4 +35,6 @@ int main()
     static_assert(cf.imag() == cd.imag(), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.special/double_long_double_explicit.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.special/double_long_double_explicit.pass.cpp
index 09f2b6ae24029f05fc871c1742386c7998e008e0..751b3b851ea34bec8b63fcf4a41a1fdb1f4b53be 100644
--- a/libcxx/test/std/numerics/complex.number/complex.special/double_long_double_explicit.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.special/double_long_double_explicit.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     const std::complex<long double> cd(2.5, 3.5);
@@ -35,4 +35,6 @@ int main()
     static_assert(cf.imag() == cd.imag(), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.special/double_long_double_implicit.fail.cpp b/libcxx/test/std/numerics/complex.number/complex.special/double_long_double_implicit.fail.cpp
index 72031e11e99224d80d75542384911beb54fa32a8..51242310a0d813d72a2404c48c4348b5167fe441 100644
--- a/libcxx/test/std/numerics/complex.number/complex.special/double_long_double_implicit.fail.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.special/double_long_double_implicit.fail.cpp
@@ -17,10 +17,12 @@
 #include <complex>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::complex<long double> cd(2.5, 3.5);
     std::complex<double> cf = cd;
     assert(cf.real() == cd.real());
     assert(cf.imag() == cd.imag());
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.special/float_double_explicit.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.special/float_double_explicit.pass.cpp
index e2074cbe36610d5e44272e1bd3385b6cd4436438..7ed53c62dfa2f8122d20e6aa50a10f2d35487a59 100644
--- a/libcxx/test/std/numerics/complex.number/complex.special/float_double_explicit.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.special/float_double_explicit.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     const std::complex<double> cd(2.5, 3.5);
@@ -35,4 +35,6 @@ int main()
     static_assert(cf.imag() == cd.imag(), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.special/float_double_implicit.fail.cpp b/libcxx/test/std/numerics/complex.number/complex.special/float_double_implicit.fail.cpp
index 66876e0bc9ac0d87cd1234b0c7750f886c10eec2..7274a2121af5a2dcada0baf366381886a7437088 100644
--- a/libcxx/test/std/numerics/complex.number/complex.special/float_double_implicit.fail.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.special/float_double_implicit.fail.cpp
@@ -17,10 +17,12 @@
 #include <complex>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::complex<double> cd(2.5, 3.5);
     std::complex<float> cf = cd;
     assert(cf.real() == cd.real());
     assert(cf.imag() == cd.imag());
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.special/float_long_double_explicit.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.special/float_long_double_explicit.pass.cpp
index 5e56346ec1a4a2c35356826b665da8fa8ad8f95f..b191bf6ea34b002b18667d4af2b9bfca2227b8e9 100644
--- a/libcxx/test/std/numerics/complex.number/complex.special/float_long_double_explicit.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.special/float_long_double_explicit.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     const std::complex<long double> cd(2.5, 3.5);
@@ -35,4 +35,6 @@ int main()
     static_assert(cf.imag() == cd.imag(), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.special/float_long_double_implicit.fail.cpp b/libcxx/test/std/numerics/complex.number/complex.special/float_long_double_implicit.fail.cpp
index 6e9bc5b3a311d93c26228db0f395c64495b0c1f0..3bf7a03767ec5dfb0da0dccfe7762cc18a549323 100644
--- a/libcxx/test/std/numerics/complex.number/complex.special/float_long_double_implicit.fail.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.special/float_long_double_implicit.fail.cpp
@@ -17,10 +17,12 @@
 #include <complex>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::complex<long double> cd(2.5, 3.5);
     std::complex<float> cf = cd;
     assert(cf.real() == cd.real());
     assert(cf.imag() == cd.imag());
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.special/long_double_double_explicit.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.special/long_double_double_explicit.pass.cpp
index 3b4ce583929d7d7db9513bb65296a54fd3ccde86..e257db2bdf1554ca02a427690afb3be3d0f7a50f 100644
--- a/libcxx/test/std/numerics/complex.number/complex.special/long_double_double_explicit.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.special/long_double_double_explicit.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     const std::complex<double> cd(2.5, 3.5);
@@ -35,4 +35,6 @@ int main()
     static_assert(cf.imag() == cd.imag(), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.special/long_double_double_implicit.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.special/long_double_double_implicit.pass.cpp
index 5f967668fb3141257ffda2da112d0fd40c9bc887..b47d945fee3235eaf6818da2129ffccb37c65ce6 100644
--- a/libcxx/test/std/numerics/complex.number/complex.special/long_double_double_implicit.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.special/long_double_double_implicit.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     const std::complex<double> cd(2.5, 3.5);
@@ -35,4 +35,6 @@ int main()
     static_assert(cf.imag() == cd.imag(), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.special/long_double_float_explicit.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.special/long_double_float_explicit.pass.cpp
index afbea2a0c698528dcd5d073d91433cc372383f1c..97f91ee07014cec34355c2fed3a41a586ed6e1a9 100644
--- a/libcxx/test/std/numerics/complex.number/complex.special/long_double_float_explicit.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.special/long_double_float_explicit.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     const std::complex<float> cd(2.5, 3.5);
@@ -35,4 +35,6 @@ int main()
     static_assert(cf.imag() == cd.imag(), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.special/long_double_float_implicit.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.special/long_double_float_implicit.pass.cpp
index e6d19736577b77cf2db0c34b3bd5e0af1d78c866..51e966d4c1c101d841c24073d8aa67f9c5c288f8 100644
--- a/libcxx/test/std/numerics/complex.number/complex.special/long_double_float_implicit.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.special/long_double_float_implicit.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     const std::complex<float> cd(2.5, 3.5);
@@ -35,4 +35,6 @@ int main()
     static_assert(cf.imag() == cd.imag(), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.synopsis/nothing_to_do.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.synopsis/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/numerics/complex.number/complex.synopsis/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.synopsis/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.transcendentals/acos.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.transcendentals/acos.pass.cpp
index 76b280af3c6cd2294845664d67a746f9ded7b91e..ecb66968905191f433ecf87bb6a7ad86b7739660 100644
--- a/libcxx/test/std/numerics/complex.number/complex.transcendentals/acos.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.transcendentals/acos.pass.cpp
@@ -129,10 +129,12 @@ void test_edges()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
     test_edges();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.transcendentals/acosh.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.transcendentals/acosh.pass.cpp
index b981e1a31d1e5ac7b436e98ee5e812e2b0c50d94..4a22dde0287d00fed9dfbabc1582306b831ab0d4 100644
--- a/libcxx/test/std/numerics/complex.number/complex.transcendentals/acosh.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.transcendentals/acosh.pass.cpp
@@ -140,10 +140,12 @@ void test_edges()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
     test_edges();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.transcendentals/asin.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.transcendentals/asin.pass.cpp
index 7d6516aebaea7a0d8342d5662011418b76b01276..91ec6e9bdabf958362913d96afdc89de49128076 100644
--- a/libcxx/test/std/numerics/complex.number/complex.transcendentals/asin.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.transcendentals/asin.pass.cpp
@@ -108,10 +108,12 @@ void test_edges()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
     test_edges();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.transcendentals/asinh.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.transcendentals/asinh.pass.cpp
index c6a6d8bb3cbe3f5c03982b8880614a94821fb727..18ac1f17a83f8e7a2afd968d521522cb67c82c36 100644
--- a/libcxx/test/std/numerics/complex.number/complex.transcendentals/asinh.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.transcendentals/asinh.pass.cpp
@@ -117,10 +117,12 @@ void test_edges()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
     test_edges();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.transcendentals/atan.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.transcendentals/atan.pass.cpp
index f4025ae736f4dd6c1f298f6493385961da47bcfd..1816e2f99b03683823eb08de254aae493100be32 100644
--- a/libcxx/test/std/numerics/complex.number/complex.transcendentals/atan.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.transcendentals/atan.pass.cpp
@@ -57,10 +57,12 @@ void test_edges()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
     test_edges();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.transcendentals/atanh.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.transcendentals/atanh.pass.cpp
index 4f037377ec6ad111c43d4ef415ef46e016bd61a2..5e4bb13f5afbf2b2cf324032a98df95d6c5dc2ba 100644
--- a/libcxx/test/std/numerics/complex.number/complex.transcendentals/atanh.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.transcendentals/atanh.pass.cpp
@@ -121,10 +121,12 @@ void test_edges()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
     test_edges();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.transcendentals/cos.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.transcendentals/cos.pass.cpp
index ff069397ada3fd3e81405440d24d640f8d007ada..2085a4c85c616d232d757cbe88a0591b457bfd1a 100644
--- a/libcxx/test/std/numerics/complex.number/complex.transcendentals/cos.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.transcendentals/cos.pass.cpp
@@ -56,10 +56,12 @@ void test_edges()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
     test_edges();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.transcendentals/cosh.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.transcendentals/cosh.pass.cpp
index eb6ef8832ed8bf9ed29dc98331e1072fc6f07765..e95c2968de6c22b607746a4ffe5c653ed5b864fd 100644
--- a/libcxx/test/std/numerics/complex.number/complex.transcendentals/cosh.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.transcendentals/cosh.pass.cpp
@@ -106,10 +106,12 @@ void test_edges()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
     test_edges();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.transcendentals/exp.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.transcendentals/exp.pass.cpp
index 9442bb08423a287ef5d6810d4016c53e67afcf34..fc638d135becded1376ad91799b18ea1f377abab 100644
--- a/libcxx/test/std/numerics/complex.number/complex.transcendentals/exp.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.transcendentals/exp.pass.cpp
@@ -104,10 +104,12 @@ void test_edges()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
     test_edges();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.transcendentals/log.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.transcendentals/log.pass.cpp
index 98d3cf45475b85ed1f53b351922b434a0a96814c..35f0c5c41b47dc7872ae75ec905ea5d2e5c530d5 100644
--- a/libcxx/test/std/numerics/complex.number/complex.transcendentals/log.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.transcendentals/log.pass.cpp
@@ -121,10 +121,12 @@ void test_edges()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
     test_edges();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.transcendentals/log10.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.transcendentals/log10.pass.cpp
index 299e037a6ed8db665ecf9948ebc3bed33aa77670..676175507c9d65c4f7145801127cf106bbf32a25 100644
--- a/libcxx/test/std/numerics/complex.number/complex.transcendentals/log10.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.transcendentals/log10.pass.cpp
@@ -55,10 +55,12 @@ void test_edges()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
     test_edges();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.transcendentals/pow_complex_complex.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.transcendentals/pow_complex_complex.pass.cpp
index 8485277927eec02f1b66b45cf149f7bbc1d93d8b..d34ab0c7ca1c198b9c6ce2df5871f222139b8d03 100644
--- a/libcxx/test/std/numerics/complex.number/complex.transcendentals/pow_complex_complex.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.transcendentals/pow_complex_complex.pass.cpp
@@ -60,10 +60,12 @@ void test_edges()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
     test_edges();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.transcendentals/pow_complex_scalar.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.transcendentals/pow_complex_scalar.pass.cpp
index 55120dcd524a0d65e7c9342bdcadfabf161b9623..7ffdd6136e66b9d545d5f2c644a9c652d391b69e 100644
--- a/libcxx/test/std/numerics/complex.number/complex.transcendentals/pow_complex_scalar.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.transcendentals/pow_complex_scalar.pass.cpp
@@ -58,10 +58,12 @@ void test_edges()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
     test_edges();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.transcendentals/pow_scalar_complex.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.transcendentals/pow_scalar_complex.pass.cpp
index 81b4b2ca765acd3498d08808c9540b82520b70bb..e4b5d3d14b6e58b1dd9066ae40653a4872c87779 100644
--- a/libcxx/test/std/numerics/complex.number/complex.transcendentals/pow_scalar_complex.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.transcendentals/pow_scalar_complex.pass.cpp
@@ -58,10 +58,12 @@ void test_edges()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
     test_edges();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.transcendentals/sin.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.transcendentals/sin.pass.cpp
index 2c2b8cbb923be2657353ae1d0a948a9e83047a9d..6e33f705454c66fb9c0a17b4f352697f5e84d666 100644
--- a/libcxx/test/std/numerics/complex.number/complex.transcendentals/sin.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.transcendentals/sin.pass.cpp
@@ -57,10 +57,12 @@ void test_edges()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
     test_edges();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.transcendentals/sinh.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.transcendentals/sinh.pass.cpp
index a2668320f68a19766455143892b075ab0abd4c11..7a9e7989830fc99b6fb568638db4038d60556e07 100644
--- a/libcxx/test/std/numerics/complex.number/complex.transcendentals/sinh.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.transcendentals/sinh.pass.cpp
@@ -107,10 +107,12 @@ void test_edges()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
     test_edges();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.transcendentals/sqrt.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.transcendentals/sqrt.pass.cpp
index 007bf2ac32def59d652fe12917fb3389acfa6f76..a0b8433022fca4e8fbab2c283836a7b127e163ef 100644
--- a/libcxx/test/std/numerics/complex.number/complex.transcendentals/sqrt.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.transcendentals/sqrt.pass.cpp
@@ -99,10 +99,12 @@ void test_edges()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
     test_edges();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.transcendentals/tan.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.transcendentals/tan.pass.cpp
index e7c80a3095c761a57e19f013c8526db59710c362..b4bc207fcccb634f5ab6b54e7f970be281fda020 100644
--- a/libcxx/test/std/numerics/complex.number/complex.transcendentals/tan.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.transcendentals/tan.pass.cpp
@@ -58,10 +58,12 @@ void test_edges()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
     test_edges();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.transcendentals/tanh.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.transcendentals/tanh.pass.cpp
index 511cdeefae333cad566feb2daa500a5700e5118f..1be3a2cd0e77690f10dd6f120c12a30d4af12a28 100644
--- a/libcxx/test/std/numerics/complex.number/complex.transcendentals/tanh.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.transcendentals/tanh.pass.cpp
@@ -89,10 +89,12 @@ void test_edges()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
     test_edges();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.value.ops/abs.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.value.ops/abs.pass.cpp
index 8fa09a7ef3a1fa0e7404c7a51927ccf01ac31c54..7a518fc378ee84abf0252bf047166c3467f4cacc 100644
--- a/libcxx/test/std/numerics/complex.number/complex.value.ops/abs.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.value.ops/abs.pass.cpp
@@ -53,10 +53,12 @@ void test_edges()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
     test_edges();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.value.ops/arg.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.value.ops/arg.pass.cpp
index 27366ec0efa3db54a4ab0a8c334d7a0e53df0fc1..280ccc8cbc4baedc71d52f59c6faaa03ea77bbc3 100644
--- a/libcxx/test/std/numerics/complex.number/complex.value.ops/arg.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.value.ops/arg.pass.cpp
@@ -125,10 +125,12 @@ void test_edges()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
     test_edges();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.value.ops/conj.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.value.ops/conj.pass.cpp
index 7d6472aa6ee906a8f738f348c256f9dab37ffd2a..8c144ffbf2f7ac3264efc5bc996fe3a3588d0548 100644
--- a/libcxx/test/std/numerics/complex.number/complex.value.ops/conj.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.value.ops/conj.pass.cpp
@@ -32,9 +32,11 @@ test()
     test(std::complex<T>(-1, -2), std::complex<T>(-1, 2));
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.value.ops/imag.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.value.ops/imag.pass.cpp
index d4bf0d8c120a48f3cfc9433db884a48c8c20bfc2..fe7cb3a96809e86708ed04e9955697f7b9940132 100644
--- a/libcxx/test/std/numerics/complex.number/complex.value.ops/imag.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.value.ops/imag.pass.cpp
@@ -23,9 +23,11 @@ test()
     assert(imag(z) == 2.5);
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.value.ops/norm.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.value.ops/norm.pass.cpp
index aeb13c80b1e684f715d38a8cede900ebf3b88c00..fe197ff21c21ae1d9312aaa106bf061b2bc5048d 100644
--- a/libcxx/test/std/numerics/complex.number/complex.value.ops/norm.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.value.ops/norm.pass.cpp
@@ -53,10 +53,12 @@ void test_edges()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
     test_edges();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.value.ops/polar.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.value.ops/polar.pass.cpp
index 3f7c497c27b834976999b18c1653d08e34565d6a..b7450abed6804904abda74a82f9fd785cd4fbbcb 100644
--- a/libcxx/test/std/numerics/complex.number/complex.value.ops/polar.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.value.ops/polar.pass.cpp
@@ -102,10 +102,12 @@ void test_edges()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
     test_edges();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.value.ops/proj.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.value.ops/proj.pass.cpp
index 6de4a0af8fab6a4d20232cf62ba06f835bb371ed..238429b5520b72197eba8cbb564d6aa9d41f58ea 100644
--- a/libcxx/test/std/numerics/complex.number/complex.value.ops/proj.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.value.ops/proj.pass.cpp
@@ -61,10 +61,12 @@ void test_edges()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
     test_edges();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex.value.ops/real.pass.cpp b/libcxx/test/std/numerics/complex.number/complex.value.ops/real.pass.cpp
index a94ba9f14012235dd7dfb2645c742fa8a21dd39e..138785900c3cc9b752daf2c6dbdbc2d7b5ee3a08 100644
--- a/libcxx/test/std/numerics/complex.number/complex.value.ops/real.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex.value.ops/real.pass.cpp
@@ -23,9 +23,11 @@ test()
     assert(real(z) == 1.5);
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/complex/types.pass.cpp b/libcxx/test/std/numerics/complex.number/complex/types.pass.cpp
index 3b2f3f7b85cc626b0d8eac72a96d566484bdfd9d..517743071dccc3992092cc77f9c726641acfe0b2 100644
--- a/libcxx/test/std/numerics/complex.number/complex/types.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/complex/types.pass.cpp
@@ -27,9 +27,11 @@ test()
     static_assert((std::is_same<typename C::value_type, T>::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/complex.number/layout.pass.cpp b/libcxx/test/std/numerics/complex.number/layout.pass.cpp
index a154f5e40ae16f1e44bc93e994a3bdfc5cd352fc..bcb81189abca4f97aa0d1e2ab724dbb8418c7218 100644
--- a/libcxx/test/std/numerics/complex.number/layout.pass.cpp
+++ b/libcxx/test/std/numerics/complex.number/layout.pass.cpp
@@ -27,9 +27,11 @@ test()
     assert(a[1] == z.imag());
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/nothing_to_do.pass.cpp b/libcxx/test/std/numerics/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/numerics/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/numerics/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/class.gslice/gslice.access/tested_elsewhere.pass.cpp b/libcxx/test/std/numerics/numarray/class.gslice/gslice.access/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/numerics/numarray/class.gslice/gslice.access/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/class.gslice/gslice.access/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/class.gslice/gslice.cons/default.pass.cpp b/libcxx/test/std/numerics/numarray/class.gslice/gslice.cons/default.pass.cpp
index 854b5cb35f1af982e144dd45153db6018af18e71..312425afbf1afdc4a5a0d1c2c5711173719959e4 100644
--- a/libcxx/test/std/numerics/numarray/class.gslice/gslice.cons/default.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/class.gslice/gslice.cons/default.pass.cpp
@@ -15,10 +15,12 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::gslice gs;
     assert(gs.start() == 0);
     assert(gs.size().size() == 0);
     assert(gs.stride().size() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/class.gslice/gslice.cons/start_size_stride.pass.cpp b/libcxx/test/std/numerics/numarray/class.gslice/gslice.cons/start_size_stride.pass.cpp
index 2faff95c7c1f00e85879fc9cea776b4c56756b16..682bb83fd1cdefebce498480dec56467e2ab4f87 100644
--- a/libcxx/test/std/numerics/numarray/class.gslice/gslice.cons/start_size_stride.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/class.gslice/gslice.cons/start_size_stride.pass.cpp
@@ -16,7 +16,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::size_t a1[] = {1, 2, 3};
     std::size_t a2[] = {4, 5, 6};
@@ -34,4 +34,6 @@ int main()
     assert(r[0] == 4);
     assert(r[1] == 5);
     assert(r[2] == 6);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/class.gslice/nothing_to_do.pass.cpp b/libcxx/test/std/numerics/numarray/class.gslice/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/numerics/numarray/class.gslice/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/class.gslice/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/class.slice/cons.slice/default.pass.cpp b/libcxx/test/std/numerics/numarray/class.slice/cons.slice/default.pass.cpp
index c03de23437d611352819b7b51e3f8bfca107c254..92c17b8a2c4997717274d1460d8ac3186ca15893 100644
--- a/libcxx/test/std/numerics/numarray/class.slice/cons.slice/default.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/class.slice/cons.slice/default.pass.cpp
@@ -15,10 +15,12 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::slice s;
     assert(s.start() == 0);
     assert(s.size() == 0);
     assert(s.stride() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/class.slice/cons.slice/start_size_stride.pass.cpp b/libcxx/test/std/numerics/numarray/class.slice/cons.slice/start_size_stride.pass.cpp
index c74f20d5ad35f7015c638a7aa295aa494992368e..72bff975712985ad34807b89906d12b1cee7bafc 100644
--- a/libcxx/test/std/numerics/numarray/class.slice/cons.slice/start_size_stride.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/class.slice/cons.slice/start_size_stride.pass.cpp
@@ -15,10 +15,12 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::slice s(1, 3, 2);
     assert(s.start() == 1);
     assert(s.size() == 3);
     assert(s.stride() == 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/class.slice/nothing_to_do.pass.cpp b/libcxx/test/std/numerics/numarray/class.slice/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/numerics/numarray/class.slice/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/class.slice/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/class.slice/slice.access/tested_elsewhere.pass.cpp b/libcxx/test/std/numerics/numarray/class.slice/slice.access/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/numerics/numarray/class.slice/slice.access/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/class.slice/slice.access/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.gslice.array/default.fail.cpp b/libcxx/test/std/numerics/numarray/template.gslice.array/default.fail.cpp
index dbad4eebb32eb70996dd97a70f216511bd161f9b..4429367cf6c7983bde30b3f0428f7217ba8b0a90 100644
--- a/libcxx/test/std/numerics/numarray/template.gslice.array/default.fail.cpp
+++ b/libcxx/test/std/numerics/numarray/template.gslice.array/default.fail.cpp
@@ -15,7 +15,9 @@
 #include <valarray>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     std::gslice_array<int> gs;
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.assign/gslice_array.pass.cpp b/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.assign/gslice_array.pass.cpp
index a2f0014279be6a93a04616317ff6ace019d3e782..3a916257b88c63d69744e1860b68593b30cbc793 100644
--- a/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.assign/gslice_array.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.assign/gslice_array.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -77,4 +77,6 @@ int main()
     assert(v1[38] == 38);
     assert(v1[39] == 39);
     assert(v1[40] == 40);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.assign/valarray.pass.cpp b/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.assign/valarray.pass.cpp
index 147c6e29d12177ba6b96fab1ede7a68d2ad9b9b7..e1aca3b7ca8945e82431085eefc35eb11812bfab 100644
--- a/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.assign/valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.assign/valarray.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -73,4 +73,6 @@ int main()
     assert(v1[38] == 38);
     assert(v1[39] == 39);
     assert(v1[40] == 40);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/addition.pass.cpp b/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/addition.pass.cpp
index fb1f3b5eeca200942b1b3b3556b604f108a44ae8..9c82a6f949166954d10cdbccf124f7028e9e9b4a 100644
--- a/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/addition.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/addition.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -73,4 +73,6 @@ int main()
     assert(v1[38] == 38);
     assert(v1[39] == 39);
     assert(v1[40] == 40);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/and.pass.cpp b/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/and.pass.cpp
index 4aa5f0245e721fe931b7f88db3036658c764ddf2..bfe8ab288df1e0d521631d209b571bbb0dcfae03 100644
--- a/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/and.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/and.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -73,4 +73,6 @@ int main()
     assert(v1[38] == 38);
     assert(v1[39] == 39);
     assert(v1[40] == 40);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/divide.pass.cpp b/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/divide.pass.cpp
index 9631d67b0bb442784ccba12a58074ca695d8b6b6..ec54bc4bb90db7170c5b97360af0530560be2a2d 100644
--- a/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/divide.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/divide.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -73,4 +73,6 @@ int main()
     assert(v1[38] == 38);
     assert(v1[39] == 39);
     assert(v1[40] == 40);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/modulo.pass.cpp b/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/modulo.pass.cpp
index d74ceaf96d3669729f11d77010ffedaeb629843d..63ad3a7778ebbc1ccef21404878d7fda4dddcd4d 100644
--- a/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/modulo.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/modulo.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -73,4 +73,6 @@ int main()
     assert(v1[38] == 38);
     assert(v1[39] == 39);
     assert(v1[40] == 40);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/multiply.pass.cpp b/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/multiply.pass.cpp
index 9ed9fcd957033e9c9d7503c59a58d632ed265a82..b22fd3015d9f1a74962c204fd684e205b02f4135 100644
--- a/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/multiply.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/multiply.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -73,4 +73,6 @@ int main()
     assert(v1[38] == 38);
     assert(v1[39] == 39);
     assert(v1[40] == 40);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/or.pass.cpp b/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/or.pass.cpp
index f6c1007e880de182ed6a7b1fbaacd7ecb64ad918..0b068935f91d56eec34a0fb14204277ec3dee8ba 100644
--- a/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/or.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/or.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -73,4 +73,6 @@ int main()
     assert(v1[38] == 38);
     assert(v1[39] == 39);
     assert(v1[40] == 40);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/shift_left.pass.cpp b/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/shift_left.pass.cpp
index 92987929e0874d9043407ed34afa4c7fcd45fbd5..912e48acab336c3d5f70bd5d89641b57e5984853 100644
--- a/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/shift_left.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/shift_left.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -73,4 +73,6 @@ int main()
     assert(v1[38] == 38);
     assert(v1[39] == 39);
     assert(v1[40] == 40);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/shift_right.pass.cpp b/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/shift_right.pass.cpp
index e617158498e1a9fb92c5f640493c50c0d0dd86a6..2c8598f7b1dbd621e7f09da591071ba1bc97d05c 100644
--- a/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/shift_right.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/shift_right.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -73,4 +73,6 @@ int main()
     assert(v1[38] == 38);
     assert(v1[39] == 39);
     assert(v1[40] == 40);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/subtraction.pass.cpp b/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/subtraction.pass.cpp
index 6b5075e05f7229d84b05d74f6ad6a6d550ce0f72..8b1271b04c73729992b75251f8e8e63d8a54ff2c 100644
--- a/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/subtraction.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/subtraction.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -73,4 +73,6 @@ int main()
     assert(v1[38] == 38);
     assert(v1[39] == 39);
     assert(v1[40] == 40);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/xor.pass.cpp b/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/xor.pass.cpp
index 285e44cde693f3f2e9a9b376274363ba0238f814..9a981ece8296f13c390a9dba10b9a0b8dea001e8 100644
--- a/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/xor.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.comp.assign/xor.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -73,4 +73,6 @@ int main()
     assert(v1[38] == 38);
     assert(v1[39] == 39);
     assert(v1[40] == 40);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.fill/assign_value.pass.cpp b/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.fill/assign_value.pass.cpp
index d3e987078980de9e88fe22d944056ee11321bd94..c7c09258093599cc6fb666e933aa142e492765af 100644
--- a/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.fill/assign_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.gslice.array/gslice.array.fill/assign_value.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -70,4 +70,6 @@ int main()
     assert(v1[38] == 38);
     assert(v1[39] == 39);
     assert(v1[40] == 40);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.gslice.array/types.pass.cpp b/libcxx/test/std/numerics/numarray/template.gslice.array/types.pass.cpp
index 4fcc77177576869f9a5dfa77b9147b216016c291..9263c0e051f120f192d7d6cdc20ebc380d040f12 100644
--- a/libcxx/test/std/numerics/numarray/template.gslice.array/types.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.gslice.array/types.pass.cpp
@@ -17,7 +17,9 @@
 #include <valarray>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::gslice_array<int>::value_type, int>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.indirect.array/default.fail.cpp b/libcxx/test/std/numerics/numarray/template.indirect.array/default.fail.cpp
index 203a9172686a5be4f9ec84570344f9cca6e8bc5b..988cdad9048d4bf912117d3bb7ec52f37a8ebbef 100644
--- a/libcxx/test/std/numerics/numarray/template.indirect.array/default.fail.cpp
+++ b/libcxx/test/std/numerics/numarray/template.indirect.array/default.fail.cpp
@@ -15,7 +15,9 @@
 #include <valarray>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     std::indirect_array<int> ia;
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.assign/indirect_array.pass.cpp b/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.assign/indirect_array.pass.cpp
index 5b27d5e0a3461344433d214e90e141463741732d..c19152bb9bd2b1d6a02be82c73ca7364067f3e2e 100644
--- a/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.assign/indirect_array.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.assign/indirect_array.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -76,4 +76,6 @@ int main()
     assert(v1[38] == 38);
     assert(v1[39] == 39);
     assert(v1[40] == 40);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.assign/valarray.pass.cpp b/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.assign/valarray.pass.cpp
index f3f0a49a4f1bf35123201281a51897335fa39f60..0bc4b58179ab2c05d7f9b8d780f271190067e676 100644
--- a/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.assign/valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.assign/valarray.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -73,4 +73,6 @@ int main()
     assert(v1[38] == 38);
     assert(v1[39] == 39);
     assert(v1[40] == 40);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/addition.pass.cpp b/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/addition.pass.cpp
index 297b9ed85a91be8cd86624849f02528d09bcb052..3ed95f9cb1e21124c9104fee0d9e2d6d0167a33d 100644
--- a/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/addition.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/addition.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -73,4 +73,6 @@ int main()
     assert(v1[38] == 38);
     assert(v1[39] == 39);
     assert(v1[40] == 40);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/and.pass.cpp b/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/and.pass.cpp
index 1dcb9c0b1df6f6724baeb0867f90bae64152ea50..00fd2f18da72afc9786522ee7b8bf6d9ed9a848a 100644
--- a/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/and.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/and.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -73,4 +73,6 @@ int main()
     assert(v1[38] == 38);
     assert(v1[39] == 39);
     assert(v1[40] == 40);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/divide.pass.cpp b/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/divide.pass.cpp
index 1112bca9f56bc1f181a95629689b692fda90bcc6..1a9ca265ad9f2dd98b93470a3a69e9f48ea7ba3a 100644
--- a/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/divide.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/divide.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -73,4 +73,6 @@ int main()
     assert(v1[38] == 38);
     assert(v1[39] == 39);
     assert(v1[40] == 40);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/modulo.pass.cpp b/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/modulo.pass.cpp
index 061735a261481c864b60f9edc9d0903f2830ff91..bad0b950e35bfca3d0fd3e4b5895457d7bcbda0d 100644
--- a/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/modulo.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/modulo.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -73,4 +73,6 @@ int main()
     assert(v1[38] == 38);
     assert(v1[39] == 39);
     assert(v1[40] == 40);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/multiply.pass.cpp b/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/multiply.pass.cpp
index d64ff33f1d789f886d7adc163b8e8eed40af13b1..7e78f0a8f39f9a37c32374220ccac1515b52791d 100644
--- a/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/multiply.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/multiply.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -73,4 +73,6 @@ int main()
     assert(v1[38] == 38);
     assert(v1[39] == 39);
     assert(v1[40] == 40);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/or.pass.cpp b/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/or.pass.cpp
index 11240333ca850a9c5ac9d16b20732262efa5be23..ba32accc64a42ca1417b2eceea5e10317681839a 100644
--- a/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/or.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/or.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -73,4 +73,6 @@ int main()
     assert(v1[38] == 38);
     assert(v1[39] == 39);
     assert(v1[40] == 40);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/shift_left.pass.cpp b/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/shift_left.pass.cpp
index 160bb8059504c8587132680c0b9763f906d81972..deff80cc3a4279f106b60bd4485a9f39bbb8166d 100644
--- a/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/shift_left.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/shift_left.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -73,4 +73,6 @@ int main()
     assert(v1[38] == 38);
     assert(v1[39] == 39);
     assert(v1[40] == 40);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/shift_right.pass.cpp b/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/shift_right.pass.cpp
index fbebc1a2514be89fca26fa8892414e338b4eda3d..d2ac739541f9aedab162c767d193cdb4b4b0b723 100644
--- a/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/shift_right.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/shift_right.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -73,4 +73,6 @@ int main()
     assert(v1[38] == 38);
     assert(v1[39] == 39);
     assert(v1[40] == 40);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/subtraction.pass.cpp b/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/subtraction.pass.cpp
index 1d4a5bf141e47d5c5a52a6a83371ac08c1a5c80f..d94422c09276a7bf1c3c5217687fab2915ecf296 100644
--- a/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/subtraction.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/subtraction.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -73,4 +73,6 @@ int main()
     assert(v1[38] == 38);
     assert(v1[39] == 39);
     assert(v1[40] == 40);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/xor.pass.cpp b/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/xor.pass.cpp
index 0a643445453d5839c6e5ce44a366b9fa40d9cb48..06e06682740ff7a3e768786a71ba7568db55f17f 100644
--- a/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/xor.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.comp.assign/xor.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -73,4 +73,6 @@ int main()
     assert(v1[38] == 38);
     assert(v1[39] == 39);
     assert(v1[40] == 40);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.fill/assign_value.pass.cpp b/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.fill/assign_value.pass.cpp
index d49f2a0f6ac0f2a2dc47dbfef05b5a54731d0c46..e327d2630e84def2c0bccd6329e22056b30b0c19 100644
--- a/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.fill/assign_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.indirect.array/indirect.array.fill/assign_value.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -70,4 +70,6 @@ int main()
     assert(v1[38] == 38);
     assert(v1[39] == 39);
     assert(v1[40] == 40);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.indirect.array/types.pass.cpp b/libcxx/test/std/numerics/numarray/template.indirect.array/types.pass.cpp
index 6cc9988aa91ed734872eae84a1bb2b62613ad252..5d06c5baf677eb2dc9e61bbf00d8efc266497153 100644
--- a/libcxx/test/std/numerics/numarray/template.indirect.array/types.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.indirect.array/types.pass.cpp
@@ -17,7 +17,9 @@
 #include <valarray>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::indirect_array<int>::value_type, int>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.mask.array/default.fail.cpp b/libcxx/test/std/numerics/numarray/template.mask.array/default.fail.cpp
index 5bec2dcad6158d47f628901b128e352d82545f2b..f22298bf9079ddd3c07af87b7ee1bcf199f29c83 100644
--- a/libcxx/test/std/numerics/numarray/template.mask.array/default.fail.cpp
+++ b/libcxx/test/std/numerics/numarray/template.mask.array/default.fail.cpp
@@ -15,7 +15,9 @@
 #include <valarray>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     std::mask_array<int> s;
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.assign/mask_array.pass.cpp b/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.assign/mask_array.pass.cpp
index d160405562977cec8692faf776e5ee80ebdf1728..22ce22ad62c010639e3dc2cc301e0a45f7ec6c8b 100644
--- a/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.assign/mask_array.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.assign/mask_array.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
@@ -62,4 +62,6 @@ int main()
     std::mask_array<int> const & r = (m1 = m2);
     assert(&r == &m1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.assign/valarray.pass.cpp b/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.assign/valarray.pass.cpp
index e7e0d3740a74aa4367c7a0cfc9a3a5649b16eb65..e364c442ff7a3a2257a40104c9d1b03e8bad4d60 100644
--- a/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.assign/valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.assign/valarray.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     const std::size_t N1 = sizeof(a1)/sizeof(a1[0]);
@@ -45,4 +45,6 @@ int main()
     assert(v1[13] == 13);
     assert(v1[14] == 14);
     assert(v1[15] == 15);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/addition.pass.cpp b/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/addition.pass.cpp
index 084a0d11b8c091ac0ab593cd44ac05361f31ae40..e8f0958b53c1229e4d761960e9e296cd53267faa 100644
--- a/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/addition.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/addition.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     const std::size_t N1 = sizeof(a1)/sizeof(a1[0]);
@@ -45,4 +45,6 @@ int main()
     assert(v1[13] == 13);
     assert(v1[14] == 14);
     assert(v1[15] == 15);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/and.pass.cpp b/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/and.pass.cpp
index e797343b619e71ac43e8921067e28e817cbd2c7d..ab2937986c2cc91c0d46b12b03429ff76995064a 100644
--- a/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/and.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/and.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     const std::size_t N1 = sizeof(a1)/sizeof(a1[0]);
@@ -45,4 +45,6 @@ int main()
     assert(v1[13] == 13);
     assert(v1[14] == 14);
     assert(v1[15] == 15);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/divide.pass.cpp b/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/divide.pass.cpp
index dc7bbb2f13841a8d04b8a0f632250860690c717c..cd67632efd0527911647782d55ce9e9ef9417cf8 100644
--- a/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/divide.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/divide.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     const std::size_t N1 = sizeof(a1)/sizeof(a1[0]);
@@ -45,4 +45,6 @@ int main()
     assert(v1[13] == 13);
     assert(v1[14] == 14);
     assert(v1[15] == 15);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/modulo.pass.cpp b/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/modulo.pass.cpp
index 302cdcc3e593fe040f03da9f4d67bcfb0f1a7255..7cf8b585d0347cb5476d68c5ec7cbad53092971b 100644
--- a/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/modulo.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/modulo.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     const std::size_t N1 = sizeof(a1)/sizeof(a1[0]);
@@ -45,4 +45,6 @@ int main()
     assert(v1[13] == 13);
     assert(v1[14] == 14);
     assert(v1[15] == 15);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/multiply.pass.cpp b/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/multiply.pass.cpp
index cfe282203ca98f1e5bee8944ac6bb7c4284d8ce2..537bf40d8d688349c3ba08a1e042f1ebc27babec 100644
--- a/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/multiply.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/multiply.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     const std::size_t N1 = sizeof(a1)/sizeof(a1[0]);
@@ -45,4 +45,6 @@ int main()
     assert(v1[13] == 13);
     assert(v1[14] == 14);
     assert(v1[15] == 15);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/or.pass.cpp b/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/or.pass.cpp
index 2fdfe0de2905ae932762f08c67570fc8d9556cfd..d0297b831e8990cbb50b14789c24373076dd1c5e 100644
--- a/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/or.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/or.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     const std::size_t N1 = sizeof(a1)/sizeof(a1[0]);
@@ -45,4 +45,6 @@ int main()
     assert(v1[13] == 13);
     assert(v1[14] == 14);
     assert(v1[15] == 15);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/shift_left.pass.cpp b/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/shift_left.pass.cpp
index aaf6f2d43ff71d287a33c739e4bf5033e37cbf01..eee4c1d461c96da1bf29c86cfe31f97b24815124 100644
--- a/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/shift_left.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/shift_left.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     const std::size_t N1 = sizeof(a1)/sizeof(a1[0]);
@@ -45,4 +45,6 @@ int main()
     assert(v1[13] == 13);
     assert(v1[14] == 14);
     assert(v1[15] == 15);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/shift_right.pass.cpp b/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/shift_right.pass.cpp
index 15d745e0208ad3acd1d47a64778ca44a10fec148..b65c19f99c43eff8eb75d8589cab53d01496f65c 100644
--- a/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/shift_right.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/shift_right.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     const std::size_t N1 = sizeof(a1)/sizeof(a1[0]);
@@ -45,4 +45,6 @@ int main()
     assert(v1[13] == 13);
     assert(v1[14] == 14);
     assert(v1[15] == 15);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/subtraction.pass.cpp b/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/subtraction.pass.cpp
index 7b09a0ec489f4551a45f946d12e00d9da26429cf..40fddd123a08d50dda363b5b4a86d72681c350e2 100644
--- a/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/subtraction.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/subtraction.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     const std::size_t N1 = sizeof(a1)/sizeof(a1[0]);
@@ -45,4 +45,6 @@ int main()
     assert(v1[13] == 13);
     assert(v1[14] == 14);
     assert(v1[15] == 15);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/xor.pass.cpp b/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/xor.pass.cpp
index 5487ea024012a677af40949928bd14dd00a728f3..a04b6da270557efd0e490d294dba87470e88ecf6 100644
--- a/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/xor.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.comp.assign/xor.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     const std::size_t N1 = sizeof(a1)/sizeof(a1[0]);
@@ -45,4 +45,6 @@ int main()
     assert(v1[13] == 13);
     assert(v1[14] == 14);
     assert(v1[15] == 15);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.fill/assign_value.pass.cpp b/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.fill/assign_value.pass.cpp
index 63558d8d535507bcc5b29e01bbb6c2e8906d66a7..bb4fd85912b41f9f013f7984842574fc487b29a2 100644
--- a/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.fill/assign_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.mask.array/mask.array.fill/assign_value.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     const std::size_t N1 = sizeof(a1)/sizeof(a1[0]);
@@ -41,4 +41,6 @@ int main()
     assert(v1[13] == 13);
     assert(v1[14] == 14);
     assert(v1[15] == 15);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.mask.array/types.pass.cpp b/libcxx/test/std/numerics/numarray/template.mask.array/types.pass.cpp
index 6848c655b5663dac394786046e3a6d0916530fdb..1d4acea6f11bf4c70f1f371ba90335b2f67094ce 100644
--- a/libcxx/test/std/numerics/numarray/template.mask.array/types.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.mask.array/types.pass.cpp
@@ -17,7 +17,9 @@
 #include <valarray>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::mask_array<int>::value_type, int>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.slice.array/default.fail.cpp b/libcxx/test/std/numerics/numarray/template.slice.array/default.fail.cpp
index 59f5fdf0ec56f1742e96149bb610494ac0432554..90b1845ba5f30754717a61b8114ced0be99ec9d9 100644
--- a/libcxx/test/std/numerics/numarray/template.slice.array/default.fail.cpp
+++ b/libcxx/test/std/numerics/numarray/template.slice.array/default.fail.cpp
@@ -15,7 +15,9 @@
 #include <valarray>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     std::slice_array<int> s;
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.assign/slice_array.pass.cpp b/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.assign/slice_array.pass.cpp
index 40dc0be7101a7553c8ff1d2e9098a27ee644146f..9683c7dfbd2c1aef1b6a6e17a07c61fe9ca803ed 100644
--- a/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.assign/slice_array.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.assign/slice_array.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
@@ -50,4 +50,6 @@ int main()
     std::slice_array<int> const & s3 = (s1 = s2);
     assert(&s1 == &s3);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.assign/valarray.pass.cpp b/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.assign/valarray.pass.cpp
index 7ea08cfaea9b0a21d5ad142288484164306ff55e..88a5b44ab24f0bb4806e0f64c3aa3bbd8965057f 100644
--- a/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.assign/valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.assign/valarray.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     int a2[] = {-1, -2, -3, -4, -5};
@@ -39,4 +39,6 @@ int main()
     assert(v1[13] == -5);
     assert(v1[14] == 14);
     assert(v1[15] == 15);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/addition.pass.cpp b/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/addition.pass.cpp
index 5934c2015c4b39565c9a08b8e0f0859640aea6e5..0433877e749add83fc55583cc3add6f231fc4e1c 100644
--- a/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/addition.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/addition.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     int a2[] = {-1, -2, -3, -4, -5};
@@ -39,4 +39,6 @@ int main()
     assert(v1[13] ==  8);
     assert(v1[14] == 14);
     assert(v1[15] == 15);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/and.pass.cpp b/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/and.pass.cpp
index 3af46538bad2928afc311636272fcd4713892144..90bbe4ef33379fec60e768fda1868d464c3b9d2e 100644
--- a/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/and.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/and.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     int a2[] = {1, 2, 3, 4, 5};
@@ -39,4 +39,6 @@ int main()
     assert(v1[13] ==  5);
     assert(v1[14] == 14);
     assert(v1[15] == 15);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/divide.pass.cpp b/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/divide.pass.cpp
index 508ebbbd8cab568cf30212a5fe91caa680b59d2b..ae1383b84bdea32717ede310482c9793263a1548 100644
--- a/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/divide.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/divide.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     int a2[] = {-1, -2, -3, -4, -5};
@@ -39,4 +39,6 @@ int main()
     assert(v1[13] == -2);
     assert(v1[14] == 14);
     assert(v1[15] == 15);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/modulo.pass.cpp b/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/modulo.pass.cpp
index 7b3919e49f0873312e5bbc84d89ed94942422096..89c1acfb3817b394b3bfe104a85128fe1a5bc9c6 100644
--- a/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/modulo.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/modulo.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     int a2[] = {-1, -2, -3, -4, -5};
@@ -39,4 +39,6 @@ int main()
     assert(v1[13] ==  3);
     assert(v1[14] == 14);
     assert(v1[15] == 15);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/multiply.pass.cpp b/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/multiply.pass.cpp
index ffcd854241950ae4a4faa14ad23df1141e6b096f..b7c6b13530a187f6e36a9e33687d55836feccda9 100644
--- a/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/multiply.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/multiply.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     int a2[] = {-1, -2, -3, -4, -5};
@@ -39,4 +39,6 @@ int main()
     assert(v1[13] == -65);
     assert(v1[14] == 14);
     assert(v1[15] == 15);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/or.pass.cpp b/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/or.pass.cpp
index b405442344726dbb2a50134e09635476d2ad457e..0f37579e86d5a7ccf63548fdef08627630527f42 100644
--- a/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/or.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/or.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     int a2[] = {1, 2, 3, 4, 5};
@@ -39,4 +39,6 @@ int main()
     assert(v1[13] == 13);
     assert(v1[14] == 14);
     assert(v1[15] == 15);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/shift_left.pass.cpp b/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/shift_left.pass.cpp
index fcf51bb18570568d8d70719b7ce152ab569d0e58..547a8cd279a50ea431b3a8f70b820b8e187d8790 100644
--- a/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/shift_left.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/shift_left.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     int a2[] = {1, 2, 3, 4, 5};
@@ -39,4 +39,6 @@ int main()
     assert(v1[13] == 416);
     assert(v1[14] == 14);
     assert(v1[15] == 15);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/shift_right.pass.cpp b/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/shift_right.pass.cpp
index 4c79b559b02a6bc1ce8ab255c5290c5dd84dfaa1..99c4ef94311bd449a3d17d94ff240bcaa1201555 100644
--- a/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/shift_right.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/shift_right.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     int a2[] = {1, 2, 3, 4, 5};
@@ -39,4 +39,6 @@ int main()
     assert(v1[13] ==  0);
     assert(v1[14] == 14);
     assert(v1[15] == 15);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/subtraction.pass.cpp b/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/subtraction.pass.cpp
index aae003cf3183290747abd9190017851a6112558e..db513bc9629f178986f07d2bc4c7501bfd43d662 100644
--- a/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/subtraction.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/subtraction.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     int a2[] = {-1, -2, -3, -4, -5};
@@ -39,4 +39,6 @@ int main()
     assert(v1[13] == 18);
     assert(v1[14] == 14);
     assert(v1[15] == 15);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/xor.pass.cpp b/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/xor.pass.cpp
index afebc882049b8399619ec9c8fa8f435ad1f97886..4ecba47238e2035a84d0a08ffad1dad6805f5343 100644
--- a/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/xor.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.comp.assign/xor.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     int a2[] = {1, 2, 3, 4, 5};
@@ -39,4 +39,6 @@ int main()
     assert(v1[13] ==  8);
     assert(v1[14] == 14);
     assert(v1[15] == 15);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.fill/assign_value.pass.cpp b/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.fill/assign_value.pass.cpp
index ed1b219a654ee531ec1dc1f3a587f056e499623d..ab2156b4627282fc0a643b94c0dabf3d474fcd63 100644
--- a/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.fill/assign_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.slice.array/slice.arr.fill/assign_value.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     std::valarray<int> v1(a1, sizeof(a1)/sizeof(a1[0]));
@@ -37,4 +37,6 @@ int main()
     assert(v1[13] == 20);
     assert(v1[14] == 14);
     assert(v1[15] == 15);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.slice.array/types.pass.cpp b/libcxx/test/std/numerics/numarray/template.slice.array/types.pass.cpp
index 0d1989a48474d303c845a77db871417f4912552e..fccde7edb6bb0938e7362a7d4561b481e9043542 100644
--- a/libcxx/test/std/numerics/numarray/template.slice.array/types.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.slice.array/types.pass.cpp
@@ -17,7 +17,9 @@
 #include <valarray>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::slice_array<int>::value_type, int>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/types.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/types.pass.cpp
index 301192ef8c93dd3eca53a4e84bda77ecd4209e2c..f37ba0f77171ae78150da389334554d0e67256c2 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/types.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/types.pass.cpp
@@ -18,8 +18,10 @@
 #include <valarray>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::valarray<int>::value_type, int>::value), "");
     static_assert((std::is_same<std::valarray<double>::value_type, double>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.access/access.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.access/access.pass.cpp
index dc90dbef9bf33e0b585abba105392ac459b22f82..d92154130b88d0eac88a3003334075c775cd3989 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.access/access.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.access/access.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -29,4 +29,6 @@ int main()
             assert(v[i] == static_cast<int>(i));
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.access/const_access.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.access/const_access.pass.cpp
index a4c81440ed2a06f33765770bd2573c8f8ffa65a1..a0174ccb3ff63cbf3f298b6c57740c7ce0705848 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.access/const_access.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.access/const_access.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -27,4 +27,6 @@ int main()
             assert(v[i] == a[i]);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/copy_assign.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/copy_assign.pass.cpp
index 24f6cc54bb787266e745822deea4807ef123ffa6..777d922a43738192637f99a7a0f36a781687e2af 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/copy_assign.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/copy_assign.pass.cpp
@@ -31,7 +31,7 @@ bool operator==(const S& lhs, const S& rhs)
     return lhs.x_ == rhs.x_;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -82,4 +82,6 @@ int main()
             assert(v2[i] == v[i]);
         assert(!S::default_ctor_called);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/gslice_array_assign.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/gslice_array_assign.pass.cpp
index 625cf17a8678f84cd10df27e905257121d1724bd..df5ae916225b96a0782dd99578d5661b2b400863 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/gslice_array_assign.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/gslice_array_assign.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -54,4 +54,6 @@ int main()
     assert(v[21] == 34);
     assert(v[22] == 35);
     assert(v[23] == 36);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/indirect_array_assign.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/indirect_array_assign.pass.cpp
index 3c351d0b3f97dcea13843eec6f8b5faaced3a8f6..f8b5243b91905d8149de8e7d5c11c47d96bef81b 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/indirect_array_assign.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/indirect_array_assign.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -54,4 +54,6 @@ int main()
     assert(v[21] == 34);
     assert(v[22] == 35);
     assert(v[23] == 36);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/initializer_list_assign.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/initializer_list_assign.pass.cpp
index 4f9b60db6426acca832abf874b494521d6e98180..1f9e5a51f6ecd94a37c52c8f7f29b0711f187c1a 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/initializer_list_assign.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/initializer_list_assign.pass.cpp
@@ -33,7 +33,7 @@ bool operator==(const S& lhs, const S& rhs)
     return lhs.x_ == rhs.x_;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -80,4 +80,6 @@ int main()
             assert(v2[i] == a[i]);
         assert(!S::default_ctor_called);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/mask_array_assign.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/mask_array_assign.pass.cpp
index 592e306e70cfdadba757a37e559d95771f98f5de..aeb95a10b74d26aa9cb8eeb40fde2ff206418574 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/mask_array_assign.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/mask_array_assign.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     const std::size_t N1 = sizeof(a1)/sizeof(a1[0]);
@@ -31,4 +31,6 @@ int main()
     assert(v2[ 2] ==  4);
     assert(v2[ 3] ==  7);
     assert(v2[ 4] == 11);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/move_assign.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/move_assign.pass.cpp
index 263c093b911287ffab5b8477e654222c4a42d354..522c0a2a33e427ca4584d1cba7ce59aeb3310714 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/move_assign.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/move_assign.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -60,4 +60,6 @@ int main()
                 assert(v2[i][j] == a[i][j]);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/slice_array_assign.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/slice_array_assign.pass.cpp
index 5ccfa2e08d590af9ca23c85b43768b5608cb4f87..68b0e37d410a72c47a82fb2c5cb6d7a7e72b8b05 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/slice_array_assign.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/slice_array_assign.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     std::valarray<int> v1(a, sizeof(a)/sizeof(a[0]));
@@ -27,4 +27,6 @@ int main()
     assert(v[2] == 7);
     assert(v[3] == 10);
     assert(v[4] == 13);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/value_assign.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/value_assign.pass.cpp
index c722f8b1e240bf3f1eeff86a6f7161b6f612c4b1..3adb1465cf565a8eb6274180afcf05a2789b332a 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/value_assign.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.assign/value_assign.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -28,4 +28,6 @@ int main()
         for (std::size_t i = 0; i < v.size(); ++i)
             assert(v[i] == 7);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/and_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/and_valarray.pass.cpp
index d6f7c57d53dec7a39c272b281bd8553b9c138a89..60b30715312c7254a472fe17d96c99952c88d7d3 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/and_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/and_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -33,4 +33,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v1[i] == v3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/and_value.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/and_value.pass.cpp
index 6c37d2bc1bb15ca21dc60496829f83ee794270bf..287372150411519c8998bb0b7f3e7cb2d24a3dff 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/and_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/and_value.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -30,4 +30,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v1[i] == v2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/divide_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/divide_valarray.pass.cpp
index a5cccdc8695cdb08b576be62221af0c2450829b1..fdb9975d5d3fe3b35428f73f9ab0bebd29fbb57f 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/divide_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/divide_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -33,4 +33,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v1[i] == v3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/divide_value.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/divide_value.pass.cpp
index bff87ab95662ba09b17817dfd18942d7ea6483d4..a309767ffba3890a904a483aa2a8f84b2f2b8d07 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/divide_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/divide_value.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -30,4 +30,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v1[i] == v2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/minus_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/minus_valarray.pass.cpp
index e574de21f037efe163612653d3825497d0cc721a..a8ef9152b00f7dd6e8b2a3169b569dc74a39d6bd 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/minus_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/minus_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -33,4 +33,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v1[i] == v3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/minus_value.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/minus_value.pass.cpp
index 0dee79df70f97cd50d3d97db8e5b994472003ae5..263ac820a7201b55e70c02144cb33adc2cfddb52 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/minus_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/minus_value.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -30,4 +30,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v1[i] == v2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/modulo_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/modulo_valarray.pass.cpp
index 5dc7ca5cea4b13204bcd018e58b6fcee8e6ab738..79cfeb0c4159730560ecee48b17feeef444bad40 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/modulo_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/modulo_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -33,4 +33,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v2[i] == v3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/modulo_value.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/modulo_value.pass.cpp
index 0e306cefc222bc67985705795a30243b6b811182..b0ea0a2986bdceda52f7b94e56b63cbbf94a399a 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/modulo_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/modulo_value.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -30,4 +30,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v1[i] == v2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/or_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/or_valarray.pass.cpp
index 97e3b9b994be5dd55d32b56bbe85b83f4442f4b8..df962a044f27e3cafb15fc0ea2bccf39e7951e31 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/or_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/or_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -33,4 +33,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v1[i] == v3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/or_value.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/or_value.pass.cpp
index ba44c578df947f601c40e5c39bcc5da1fcfb7b7d..1be8942ab7a5022cf40f9da51b8a89eb193e43b8 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/or_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/or_value.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -30,4 +30,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v1[i] == v2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/plus_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/plus_valarray.pass.cpp
index 67ed8bc5c0e446afc7cc3463b140cbad9eb91742..3700e5c4758c89da663b3e564c31f1bbbac3c111 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/plus_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/plus_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -33,4 +33,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v1[i] == v3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/plus_value.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/plus_value.pass.cpp
index 730ac7f15d1f5aa5bf910062aec231e095e9f0d1..c8c5d1ef9c640a36a17bef513b087096f06e4e6c 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/plus_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/plus_value.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -30,4 +30,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v1[i] == v2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/shift_left_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/shift_left_valarray.pass.cpp
index 91ea80ed28696e87e49ecd5a86c1cd3f8f1a1fd9..f642ce4316dc21cdd1e2c0cfbac6ea7a0f3926c4 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/shift_left_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/shift_left_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -33,4 +33,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v1[i] == v3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/shift_left_value.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/shift_left_value.pass.cpp
index abbb0023cc382b9df8b509100bb19dfd68457346..8cba6b4dac5a0e05ba5bdf64049dfbd124c374ff 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/shift_left_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/shift_left_value.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -30,4 +30,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v1[i] == v2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/shift_right_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/shift_right_valarray.pass.cpp
index f5fc5c7248a451ac6ff5eb34226a4ad4d2a4a406..d50971b394daf687975d622dc5dbfd5a649e1837 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/shift_right_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/shift_right_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -33,4 +33,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v1[i] == v3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/shift_right_value.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/shift_right_value.pass.cpp
index 00f5e256026330b5865e41b9236361eaf9f41834..670599afd34598f0fe2618c6e33da14922bcd842 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/shift_right_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/shift_right_value.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -30,4 +30,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v1[i] == v2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/times_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/times_valarray.pass.cpp
index 00ac963b71ee73eb7cf4f9704557a5cebbbde0c9..f7e3da5bf9a460dadbd279ff38e4636aecd96935 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/times_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/times_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -33,4 +33,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v1[i] == v3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/times_value.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/times_value.pass.cpp
index a039f9f8c8b28049e515bc808970cdc7f6793760..9632799683b6fbcd57736f1a0d8f38d4cfe7c3a6 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/times_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/times_value.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -30,4 +30,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v1[i] == v2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/xor_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/xor_valarray.pass.cpp
index f9d8ba3b546661241e0766a5dfbb45d85c4dfe1b..bf08055117ad811ca313d72f5cc417eb15511173 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/xor_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/xor_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -33,4 +33,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v1[i] == v3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/xor_value.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/xor_value.pass.cpp
index 02c1398244c689ff4104cc010cd66f6c401ba26a..0a3d3200f90f56a5b1aa27218e218eb0e0bae85a 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/xor_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cassign/xor_value.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -30,4 +30,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v1[i] == v2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/copy.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/copy.pass.cpp
index a97a250474ed8800db289b1ec40fbc229030d5ab..8a9c6baae3a02c7b738b323f7a0cb59768056be7 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/copy.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/copy.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -52,4 +52,6 @@ int main()
                 assert(v2[i][j] == v[i][j]);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/default.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/default.pass.cpp
index ff4a7a2544415ec6d3b3b642ca8f328382405aba..b5603980244458d402120959bd856abfe0d865cf 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/default.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/default.pass.cpp
@@ -22,7 +22,7 @@ struct S {
 
 bool S::ctor_called = false;
 
-int main()
+int main(int, char**)
 {
     {
         std::valarray<int> v;
@@ -45,4 +45,6 @@ int main()
         assert(v.size() == 0);
         assert(!S::ctor_called);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/gslice_array.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/gslice_array.pass.cpp
index 7e061f50a860a896a49b0bbc1cbbae47c205cc0f..fdab3e3e8e4bbd36218fdf28d4e82d04dee72023 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/gslice_array.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/gslice_array.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -53,4 +53,6 @@ int main()
     assert(v[21] == 34);
     assert(v[22] == 35);
     assert(v[23] == 36);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/indirect_array.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/indirect_array.pass.cpp
index e525b2a4f6a8cf62a818760cfe313df87d341a5c..3a62b0a54793f50fdd73451194f47f6f0054ad46 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/indirect_array.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/indirect_array.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -53,4 +53,6 @@ int main()
     assert(v[21] == 34);
     assert(v[22] == 35);
     assert(v[23] == 36);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/initializer_list.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/initializer_list.pass.cpp
index bd47c57980b5f8a4aa8fd670757032815ecd2733..1f5986eda180689555cf8285efb3aa7104b4f053 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/initializer_list.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/initializer_list.pass.cpp
@@ -17,7 +17,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -37,4 +37,6 @@ int main()
         for (unsigned i = 0; i < N; ++i)
             assert(v[i] == a[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/mask_array.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/mask_array.pass.cpp
index e9deea94a17249f151f9bc415dbc984ef12608be..4559c36e7cac9ef1a67d4629905c95fc8a55eeb3 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/mask_array.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/mask_array.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     const std::size_t N1 = sizeof(a1)/sizeof(a1[0]);
@@ -30,4 +30,6 @@ int main()
     assert(v2[ 2] ==  4);
     assert(v2[ 3] ==  7);
     assert(v2[ 4] == 11);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/move.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/move.pass.cpp
index 010649a92b8d3dc8b2a0495add91ca3f7b37e2df..0ef6f3cee532fd2a9cc11033ff004d58ee8d26a0 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/move.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/move.pass.cpp
@@ -19,7 +19,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -58,4 +58,6 @@ int main()
                 assert(v2[i][j] == a[i][j]);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/pointer_size.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/pointer_size.pass.cpp
index 84d51b035e9c5f7915a5aee6cc34a2f852be54fd..a0b4a31aebe2ce50a96bd62430b5925bbb7fde40 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/pointer_size.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/pointer_size.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -49,4 +49,6 @@ int main()
                 assert(v[i][j] == a[i][j]);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/size.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/size.pass.cpp
index 7e539d9c21f884480f9a133d809c1c0e9186cb14..95417e58a63bc8ee53c5d3b025500177adabff9c 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/size.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/size.pass.cpp
@@ -24,7 +24,7 @@ struct S {
 
 size_t S::cnt_dtor = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::valarray<int> v(100);
@@ -51,4 +51,6 @@ int main()
             assert(v[i].x == 1);
     }
     assert(S::cnt_dtor == 100);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/slice_array.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/slice_array.pass.cpp
index c5667671f3e57885d20846f2d056f8136676aba6..332a617153d641ceda15a182a286f0dc39e4da83 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/slice_array.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/slice_array.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     std::valarray<int> v1(a, sizeof(a)/sizeof(a[0]));
@@ -26,4 +26,6 @@ int main()
     assert(v[2] == 7);
     assert(v[3] == 10);
     assert(v[4] == 13);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/value_size.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/value_size.pass.cpp
index 6e43de782bce2747baecf6c8b3f3134e6cfef0af..03e4add4648a0324ee832d9cb444134136552ce3 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/value_size.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.cons/value_size.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::valarray<int> v(5, 100);
@@ -35,4 +35,6 @@ int main()
         for (int i = 0; i < 100; ++i)
             assert(v[i].size() == 10);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/apply_cref.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/apply_cref.pass.cpp
index 7d4d079231a4e627aa114d4d16ec8748a12fbca5..65277870aa57ba58352fd678814486718abb299c 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/apply_cref.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/apply_cref.pass.cpp
@@ -19,7 +19,7 @@ typedef int T;
 
 T f(const T& t) {return t + 5;}
 
-int main()
+int main(int, char**)
 {
     {
         T a1[] = {1, 2, 3, 4,  5,  6,  7,  8,  9, 10};
@@ -47,4 +47,6 @@ int main()
         for (unsigned i = 0; i < N1; ++i)
             assert(v2[i] == a2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/apply_value.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/apply_value.pass.cpp
index d43810062f64019ed320eb161c3f9f5388ea5854..fd100b5e54e6d03c21abf6d45a46fbb1963ae242 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/apply_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/apply_value.pass.cpp
@@ -19,7 +19,7 @@ typedef int T;
 
 T f(T t) {return t + 5;}
 
-int main()
+int main(int, char**)
 {
     {
         T a1[] = {1, 2, 3, 4,  5,  6,  7,  8,  9, 10};
@@ -47,4 +47,6 @@ int main()
         for (unsigned i = 0; i < N1; ++i)
             assert(v2[i] == a2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/cshift.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/cshift.pass.cpp
index 1aa6a3e9abb656c714b56a22c083a150dd74cdc7..14ca081a1e918060e929ffbadbf99dceff0b0b8f 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/cshift.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/cshift.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -123,4 +123,6 @@ int main()
         for (unsigned i = 0; i < N1; ++i)
             assert(v2[i] == a2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/max.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/max.pass.cpp
index cc80ea8e07f1b8344fdf4d20cefabf6b3c0e7c40..bdd84c118367af82b6442598519197da85a125d6 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/max.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/max.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -36,4 +36,6 @@ int main()
         std::valarray<T> v1(a1, N1);
         assert((2*v1).max() == 8.0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/min.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/min.pass.cpp
index 37d8f3a313645400cab8094eecadb4451032304f..ca04a930853d5cba0d4f90c4bd039bb75694d694 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/min.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/min.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -36,4 +36,6 @@ int main()
         std::valarray<T> v1(a1, N1);
         assert((2*v1).min() == -6.0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/resize.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/resize.pass.cpp
index 82dd0bd38aacc7e0adf3ae773a7eaa443b762345..e92e7420b3cb0f58db59ade63327b7c21a9c1753 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/resize.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/resize.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -38,4 +38,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v1[i] == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/shift.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/shift.pass.cpp
index 2be57bff3fd3935faaf4670c2aef6b90a13ccb5e..1a7628eb34951877ee2ea720ee980b4f3dc419db 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/shift.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/shift.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -123,4 +123,6 @@ int main()
         for (unsigned i = 0; i < N1; ++i)
             assert(v2[i] == a2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/size.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/size.pass.cpp
index 3498cc59cb55ce67bcb6b47577e6c164a18d0e4d..f790627233de8721eceb806211ebd831b099a509 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/size.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/size.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -37,4 +37,6 @@ int main()
         std::valarray<T> v1;
         assert(v1.size() == N1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/sum.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/sum.pass.cpp
index b1c530aa4fe479e8bc8cd8f8efe5e74bee94ef15..084f00fb97ee1384993d9cf2545d0605dfddb5ec 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/sum.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/sum.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -24,4 +24,6 @@ int main()
         std::valarray<T> v1(a1, N1);
         assert(v1.sum() == 16.5);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/swap.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/swap.pass.cpp
index 23cf807afc222145769ff7ba31951e5ddf72977e..12a7d8fd8ea6f036443c0c58c8b505ee2b9a51fc 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/swap.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.members/swap.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -82,4 +82,6 @@ int main()
         for (std::size_t i = 0; i < v2.size(); ++i)
             assert(v2[i] == v1_save[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/gslice_const.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/gslice_const.pass.cpp
index 32e6b5561a81bf4b5d96377ea83d42b8fb29644d..d84309f221e97057bf4c597d87daee9a1b248f98 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/gslice_const.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/gslice_const.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -73,4 +73,6 @@ int main()
     assert(v1[38] == 38);
     assert(v1[39] == 39);
     assert(v1[40] == 40);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/gslice_non_const.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/gslice_non_const.pass.cpp
index 12caa6118a296941e9a3d775a02f964b40c51818..ac697187806660692780bdb71768c765e0c531e9 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/gslice_non_const.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/gslice_non_const.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -53,4 +53,6 @@ int main()
     assert(v[21] == 34);
     assert(v[22] == 35);
     assert(v[23] == 36);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/indirect_array_const.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/indirect_array_const.pass.cpp
index d210e5120dc3fdcb027709334357f32cc3d10ae1..7e5ef154648856920873dcd23f615d4bee37e605 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/indirect_array_const.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/indirect_array_const.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -53,4 +53,6 @@ int main()
     assert(v[21] == 34);
     assert(v[22] == 35);
     assert(v[23] == 36);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/indirect_array_non_const.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/indirect_array_non_const.pass.cpp
index 053e9267e72c567fed9d8d61125e91e7b5cceaa6..82a5f14485a160904fa7d4a5d245114776f338a1 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/indirect_array_non_const.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/indirect_array_non_const.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11,
                12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
@@ -54,4 +54,6 @@ int main()
     assert(v[21] == 34);
     assert(v[22] == 35);
     assert(v[23] == 36);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/slice_const.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/slice_const.pass.cpp
index 3eaafee7ee8f8075a48cd069daea2b5ae6e0f160..d689ce9236e5ed209073325fda7b98f7105ec556 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/slice_const.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/slice_const.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     std::valarray<int> v1(a1, sizeof(a1)/sizeof(a1[0]));
@@ -26,4 +26,6 @@ int main()
     assert(v2[2] ==  7);
     assert(v2[3] == 10);
     assert(v2[4] == 13);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/slice_non_const.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/slice_non_const.pass.cpp
index d4cb64cf96419c8b3993628949e95a0b714a6947..a6c7cb7e884d58724300881e8a37849004946e84 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/slice_non_const.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/slice_non_const.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     int a2[] = {-1, -2, -3, -4, -5};
@@ -39,4 +39,6 @@ int main()
     assert(v1[13] == -5);
     assert(v1[14] == 14);
     assert(v1[15] == 15);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/valarray_bool_const.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/valarray_bool_const.pass.cpp
index 77e86ac7312fa8f70f3f1f7cfc4c38012c991f8b..13cafbccb482b5cc1adc81c2f753d774aa2eb4d7 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/valarray_bool_const.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/valarray_bool_const.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     const std::size_t N1 = sizeof(a1)/sizeof(a1[0]);
@@ -30,4 +30,6 @@ int main()
     assert(v2[ 2] ==  4);
     assert(v2[ 3] ==  7);
     assert(v2[ 4] == 11);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/valarray_bool_non_const.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/valarray_bool_non_const.pass.cpp
index 6ea9e18496dac57bc587d9f1f61c011a80bd56a9..34b4cfdb5f688579c330d5bec783dcf10c3f719f 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/valarray_bool_non_const.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.sub/valarray_bool_non_const.pass.cpp
@@ -15,7 +15,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
     const std::size_t N1 = sizeof(a1)/sizeof(a1[0]);
@@ -31,4 +31,6 @@ int main()
     assert(v2[ 2] ==  4);
     assert(v2[ 3] ==  7);
     assert(v2[ 4] == 11);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.unary/bit_not.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.unary/bit_not.pass.cpp
index 8bb23c0b45c384904b54001b922bd1b77e9a0c8a..7f31355d0e0401fd4b10da32e6d883e1ede77974 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.unary/bit_not.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.unary/bit_not.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -52,4 +52,6 @@ int main()
         for (std::size_t i = 0; i < v2.size(); ++i)
             assert(v2[i] == ~(2*v[i]));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.unary/negate.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.unary/negate.pass.cpp
index 2827488d275f5d1bb554a379a1567314381f7aa8..a89b24d233b139cc8303a749eefcffc353c4af3b 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.unary/negate.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.unary/negate.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -62,4 +62,6 @@ int main()
         for (std::size_t i = 0; i < v2.size(); ++i)
             assert(v2[i] == -2*v[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.unary/not.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.unary/not.pass.cpp
index 64e902146a2bbbbc0827d1eb0f04d2b183dd6568..3975510fba76c578f5c25fae79f2d8a071e21c3e 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.unary/not.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.unary/not.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -38,4 +38,6 @@ int main()
         for (std::size_t i = 0; i < v2.size(); ++i)
             assert(v2[i] == !(2 * v[i]));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/template.valarray/valarray.unary/plus.pass.cpp b/libcxx/test/std/numerics/numarray/template.valarray/valarray.unary/plus.pass.cpp
index 113bb12e96efe7cf2b65f7c7f429c25b75a7a44b..b1f7f313f3f498cb731881085a9da20c3451e603 100644
--- a/libcxx/test/std/numerics/numarray/template.valarray/valarray.unary/plus.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/template.valarray/valarray.unary/plus.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -62,4 +62,6 @@ int main()
         for (std::size_t i = 0; i < v2.size(); ++i)
             assert(v2[i] == +2*v[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/nothing_to_do.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/and_valarray_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/and_valarray_valarray.pass.cpp
index d195f1d248ab8bde227614e5b405661dab0b3260..3be9074db3c8e3c293d7be6fedc93f7b2b6dbde8 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/and_valarray_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/and_valarray_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -32,4 +32,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/and_valarray_value.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/and_valarray_value.pass.cpp
index 4e083bd15d85e1ec6a17bf74c5fba27080b1ca2b..4f1bf8ad66b4e1142a1821f31e61cb8d16564714 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/and_valarray_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/and_valarray_value.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -29,4 +29,6 @@ int main()
         for (std::size_t i = 0; i < v2.size(); ++i)
             assert(v2[i] == a2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/and_value_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/and_value_valarray.pass.cpp
index 89fdd065a2d9a3de5332b43c3327fc6ac039b4bd..05990124e2615ee1553b7638510f7ab323a87708 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/and_value_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/and_value_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -29,4 +29,6 @@ int main()
         for (std::size_t i = 0; i < v2.size(); ++i)
             assert(v2[i] == a2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/divide_valarray_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/divide_valarray_valarray.pass.cpp
index 4b76423ae8cf6adc8abe1443307c5ef0fad3a2e7..50c6a14848aadba762fec6df2106d2d5758da224 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/divide_valarray_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/divide_valarray_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -32,4 +32,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/divide_valarray_value.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/divide_valarray_value.pass.cpp
index babecfe99679a5e97e3f637efced97be2cded6e7..f5e0b27271ab7604e7a5809f4dbb57fe0befbd64 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/divide_valarray_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/divide_valarray_value.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -29,4 +29,6 @@ int main()
         for (std::size_t i = 0; i < v2.size(); ++i)
             assert(v2[i] == a2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/divide_value_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/divide_value_valarray.pass.cpp
index 29316e4c7c4d1fc99e8b078bc7e53dccefa1562f..dde6955bbb717f8ba0207d46f9caaee1ee8d8d89 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/divide_value_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/divide_value_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -29,4 +29,6 @@ int main()
         for (std::size_t i = 0; i < v2.size(); ++i)
             assert(v2[i] == a2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/minus_valarray_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/minus_valarray_valarray.pass.cpp
index af78964cace4f2a4b61fe4bd0b02d1a538616fb1..f1df168b3554a016d6fcdf38aa958a4a229b2c9b 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/minus_valarray_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/minus_valarray_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -32,4 +32,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/minus_valarray_value.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/minus_valarray_value.pass.cpp
index e6760c2306a6b73a25113dbf7c91e611430c6b75..0ea4f0c1d8847ab3fc4589792c3e0308324ea3de 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/minus_valarray_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/minus_valarray_value.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -29,4 +29,6 @@ int main()
         for (std::size_t i = 0; i < v2.size(); ++i)
             assert(v2[i] == a2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/minus_value_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/minus_value_valarray.pass.cpp
index 1d984be798e6fbceeca016af0d8ba81419c08e80..f2131d10e0cdc83792d6758a0c4a9e7f205db138 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/minus_value_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/minus_value_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -29,4 +29,6 @@ int main()
         for (std::size_t i = 0; i < v2.size(); ++i)
             assert(v2[i] == a2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/modulo_valarray_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/modulo_valarray_valarray.pass.cpp
index 948688ba3a0591dd0dd87f8d24467940bccb11a2..22d82f4b57e521b7faf105f7839121856c76f91c 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/modulo_valarray_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/modulo_valarray_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -32,4 +32,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/modulo_valarray_value.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/modulo_valarray_value.pass.cpp
index 101b32d5309a4aa2aa2e0beaa543fb1f1802543d..f498e7af58888de7a930059ede59744563a78df7 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/modulo_valarray_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/modulo_valarray_value.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -29,4 +29,6 @@ int main()
         for (std::size_t i = 0; i < v2.size(); ++i)
             assert(v2[i] == a2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/modulo_value_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/modulo_value_valarray.pass.cpp
index dc2ecc0f8d33d61bced0c9833d5d5c808b33860e..fbd407ce29ab4d66aa886ae99599417828ef8609 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/modulo_value_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/modulo_value_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -29,4 +29,6 @@ int main()
         for (std::size_t i = 0; i < v2.size(); ++i)
             assert(v2[i] == a2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/or_valarray_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/or_valarray_valarray.pass.cpp
index c01d33a2bd480a7c5c3a11a68bdfbfc883c2a6e0..f305243d5a5da9185a50d4096e26e16f135cd34c 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/or_valarray_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/or_valarray_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -32,4 +32,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/or_valarray_value.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/or_valarray_value.pass.cpp
index 328afb2a462043684fa75c6d3b657f186d1d94e8..90fa4b4fd027557489f913d371a69b79aca1bb20 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/or_valarray_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/or_valarray_value.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -29,4 +29,6 @@ int main()
         for (std::size_t i = 0; i < v2.size(); ++i)
             assert(v2[i] == a2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/or_value_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/or_value_valarray.pass.cpp
index e5ca459632e26496e11b2a5df11a0771f036c161..295dd6bdc5fed7d7521731df48ceb4cf0b8d81e1 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/or_value_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/or_value_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -29,4 +29,6 @@ int main()
         for (std::size_t i = 0; i < v2.size(); ++i)
             assert(v2[i] == a2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/plus_valarray_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/plus_valarray_valarray.pass.cpp
index c65a7b2a6c62516a67dec3cd98886fbe78600e2d..19a410e4faaeae6fc43cf0833d9a4ef8d4f3f0bb 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/plus_valarray_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/plus_valarray_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -32,4 +32,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/plus_valarray_value.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/plus_valarray_value.pass.cpp
index 46b7fbb559128e7d28e5f1b5800b325d4bf932ca..2aef9c1a174515a35f045ca5f4937d787b07e7b8 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/plus_valarray_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/plus_valarray_value.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -29,4 +29,6 @@ int main()
         for (std::size_t i = 0; i < v2.size(); ++i)
             assert(v2[i] == a2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/plus_value_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/plus_value_valarray.pass.cpp
index 97b7791deda137cd344a685b24fdcd094d7a510e..ba598f62ddc7af2ab4a3fdcdc0851545f0e23081 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/plus_value_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/plus_value_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -29,4 +29,6 @@ int main()
         for (std::size_t i = 0; i < v2.size(); ++i)
             assert(v2[i] == a2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/shift_left_valarray_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/shift_left_valarray_valarray.pass.cpp
index 90f9d756c6dc49a970418d95a3d7dddf0e8e8802..e71fa1056ead75fdc932c746f29f35110dc8e0a3 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/shift_left_valarray_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/shift_left_valarray_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -32,4 +32,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/shift_left_valarray_value.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/shift_left_valarray_value.pass.cpp
index 5136d3fd99a3b0517deec555f7979faacdb1a187..3945c1bf4547b4f1edcb36ef78b05aee7d984689 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/shift_left_valarray_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/shift_left_valarray_value.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -29,4 +29,6 @@ int main()
         for (std::size_t i = 0; i < v2.size(); ++i)
             assert(v2[i] == a2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/shift_left_value_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/shift_left_value_valarray.pass.cpp
index 697b46db846ec4117ebda4c4f50187e141723e17..93276345210fbb51397c407543bccf1a44b4afa5 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/shift_left_value_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/shift_left_value_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -29,4 +29,6 @@ int main()
         for (std::size_t i = 0; i < v2.size(); ++i)
             assert(v2[i] == a2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/shift_right_valarray_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/shift_right_valarray_valarray.pass.cpp
index 4194c191a24face074da7ef07271231f9c2dc1d5..9422d6be871c7b414e35650aca828bf492b7f316 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/shift_right_valarray_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/shift_right_valarray_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -32,4 +32,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/shift_right_valarray_value.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/shift_right_valarray_value.pass.cpp
index 4aabb8a941cca3c80d7add24fba7fe85e82501d9..8a68f30ca6f8a4e6233940d0153bbe394e557da8 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/shift_right_valarray_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/shift_right_valarray_value.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -29,4 +29,6 @@ int main()
         for (std::size_t i = 0; i < v2.size(); ++i)
             assert(v2[i] == a2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/shift_right_value_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/shift_right_value_valarray.pass.cpp
index cccdca18ca4b111df3c7df76e3347389cb2ec282..519fd2b3bd9d2e6a3725c31d87f5b4bcb78f481c 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/shift_right_value_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/shift_right_value_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -29,4 +29,6 @@ int main()
         for (std::size_t i = 0; i < v2.size(); ++i)
             assert(v2[i] == a2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/times_valarray_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/times_valarray_valarray.pass.cpp
index c15b794ce35838a06a85cc99d4721e5a73898028..bc5e7329c8a1d32c1b0dc092fd77654d8b30c18b 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/times_valarray_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/times_valarray_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -32,4 +32,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/times_valarray_value.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/times_valarray_value.pass.cpp
index 155ea25b580ca30f31d1e848ceab13f6f3f2eab1..330f5e0a70b206ccd956d0e99ca02b3ee42b67c6 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/times_valarray_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/times_valarray_value.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -29,4 +29,6 @@ int main()
         for (std::size_t i = 0; i < v2.size(); ++i)
             assert(v2[i] == a2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/times_value_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/times_value_valarray.pass.cpp
index b825ad54e1c8e79d72db52b45988c0ccdd3c1638..4fa8bb2d209661caf15561e112705ad55fa8c568 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/times_value_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/times_value_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -29,4 +29,6 @@ int main()
         for (std::size_t i = 0; i < v2.size(); ++i)
             assert(v2[i] == a2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/xor_valarray_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/xor_valarray_valarray.pass.cpp
index 5e07f5d44663de4e237998a10efd797f8ab0b421..fd4fb084c0a6581368f9b95b5a0cb2e77e298925 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/xor_valarray_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/xor_valarray_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -32,4 +32,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/xor_valarray_value.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/xor_valarray_value.pass.cpp
index bc22ebaddf0b4a90264856348d551d81222f7e1c..c5082f553c7340ce9f83aac0eaf21db170f3704d 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/xor_valarray_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/xor_valarray_value.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -29,4 +29,6 @@ int main()
         for (std::size_t i = 0; i < v2.size(); ++i)
             assert(v2[i] == a2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/xor_value_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/xor_value_valarray.pass.cpp
index 14574a10d9f9c9cd74bee25f32609d8d84d783e2..377f03ed38d5415842ad9c114026ea02cb650105 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/xor_value_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.binary/xor_value_valarray.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -29,4 +29,6 @@ int main()
         for (std::size_t i = 0; i < v2.size(); ++i)
             assert(v2[i] == a2[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/and_valarray_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/and_valarray_valarray.pass.cpp
index 3e0951b6e2d3803597a0f04373386d2ad445a38b..3f3ede056ee38ae0b072afc19c080040d7bcb7b0 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/and_valarray_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/and_valarray_valarray.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -34,4 +34,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/and_valarray_value.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/and_valarray_value.pass.cpp
index 75bce73a249200a2ec3deeea46353ba44182596f..de5808e5710b299160740e196806f6dbdbe0100b 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/and_valarray_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/and_valarray_value.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -42,4 +42,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/and_value_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/and_value_valarray.pass.cpp
index a6cd5e836d6fea17a97f952cb89f5ba5bfd073a4..c73ec1e54cb23c5b8e4ced7d794fadea69f28a70 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/and_value_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/and_value_valarray.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -42,4 +42,6 @@ int main()
         for (std::size_t i = 0; i < v3.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/equal_valarray_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/equal_valarray_valarray.pass.cpp
index 3b43c1097407db4d02502669989a6afcdcda4773..187126fc8ed1d631d6ede96bde1b62ecbd083201 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/equal_valarray_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/equal_valarray_valarray.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -34,4 +34,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/equal_valarray_value.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/equal_valarray_value.pass.cpp
index 1bd1fa0e81bd57cc01c60ceb7cb5484159d48f03..01c04a62c800264042326cabdb816190f471e81d 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/equal_valarray_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/equal_valarray_value.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -31,4 +31,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/equal_value_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/equal_value_valarray.pass.cpp
index 5fb05f60ae45c8817dda958a2f7c8027cb1d1175..b0db6a0d18e222e0542a50dbaf4ff16f5b429b3e 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/equal_value_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/equal_value_valarray.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -31,4 +31,6 @@ int main()
         for (std::size_t i = 0; i < v3.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/greater_equal_valarray_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/greater_equal_valarray_valarray.pass.cpp
index 6f7678fc7f542411ec2fc9801fdb74ebeb4a88dc..c8de6208aaee4fe3e3b123db2e9661bdd638d68e 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/greater_equal_valarray_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/greater_equal_valarray_valarray.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -34,4 +34,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/greater_equal_valarray_value.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/greater_equal_valarray_value.pass.cpp
index f26e946942a1dfb6d67f69bdbb49d767b4dc7ad5..cf568b5307b263b5be9042410ea4de47d903572c 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/greater_equal_valarray_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/greater_equal_valarray_value.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -31,4 +31,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/greater_equal_value_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/greater_equal_value_valarray.pass.cpp
index 2c795aae311734219698ff620900af9a57d31b72..c66a60e062c89765d32e4d983cc83004e4c28c94 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/greater_equal_value_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/greater_equal_value_valarray.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -31,4 +31,6 @@ int main()
         for (std::size_t i = 0; i < v3.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/greater_valarray_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/greater_valarray_valarray.pass.cpp
index 03468763f1350078299efae3676c4a107b164ce7..351b662be07bb0c60dd65424db228b3ad195ea16 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/greater_valarray_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/greater_valarray_valarray.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -34,4 +34,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/greater_valarray_value.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/greater_valarray_value.pass.cpp
index 970f8d8d567929eff3032b92c210d461cd5031f7..f895b0783b714542ba794ba60c528e55a9c0ca7e 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/greater_valarray_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/greater_valarray_value.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -31,4 +31,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/greater_value_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/greater_value_valarray.pass.cpp
index ad30ae4254143bc7b826ade741d9357a9dea9f9c..a54b770256beaed54b13ac5e2c6980f772210ef7 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/greater_value_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/greater_value_valarray.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -31,4 +31,6 @@ int main()
         for (std::size_t i = 0; i < v3.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/less_equal_valarray_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/less_equal_valarray_valarray.pass.cpp
index 86e5553a8cd86f1125f0d01ed72a9aad068f904f..c8812f3fd89ec8b3b0f73712522e126c13420018 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/less_equal_valarray_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/less_equal_valarray_valarray.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -34,4 +34,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/less_equal_valarray_value.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/less_equal_valarray_value.pass.cpp
index d520a21b96534a7a5919de246dee762b07846dac..03caf34a60a394344bb99712612ccac97227989d 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/less_equal_valarray_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/less_equal_valarray_value.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -31,4 +31,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/less_equal_value_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/less_equal_value_valarray.pass.cpp
index 2055f7554a11ee65f436f13784e5389213fc7572..5026b73d4e21e86109420dde6dc8cb7f39a51d80 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/less_equal_value_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/less_equal_value_valarray.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -31,4 +31,6 @@ int main()
         for (std::size_t i = 0; i < v3.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/less_valarray_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/less_valarray_valarray.pass.cpp
index 0eb137ca07a9e6a392c8ca1a29ba5c203e01408b..59943f912e3bd8888ea2d14c79bf1bd99632b7cb 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/less_valarray_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/less_valarray_valarray.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -34,4 +34,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/less_valarray_value.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/less_valarray_value.pass.cpp
index d7d6b7d8b4422d378c4c63d0d903d23c82ec8906..9ced475713922dac271cdc61c1ac3aaad095afe1 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/less_valarray_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/less_valarray_value.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -31,4 +31,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/less_value_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/less_value_valarray.pass.cpp
index 34419bdece0153fa88ce2cbe230846e59582f280..770d5a96f7dca97e9dc2c5910acb88840684951a 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/less_value_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/less_value_valarray.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -31,4 +31,6 @@ int main()
         for (std::size_t i = 0; i < v3.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/not_equal_valarray_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/not_equal_valarray_valarray.pass.cpp
index 4daca5332a8740943e86400d3407372d11ccb378..1892a70717639ec89f2c04bf10545955e4555288 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/not_equal_valarray_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/not_equal_valarray_valarray.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -34,4 +34,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/not_equal_valarray_value.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/not_equal_valarray_value.pass.cpp
index add76d16c007b4ebd0d556dddf828857f27ccf4c..3cdb89739583a3104136f34e08ffe8be2a65e969 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/not_equal_valarray_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/not_equal_valarray_value.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -31,4 +31,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/not_equal_value_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/not_equal_value_valarray.pass.cpp
index a35038051401073f584f60e3a41324a4fdfc7b86..49ffeda05ae5c7396f10ac54471529368ad07475 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/not_equal_value_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/not_equal_value_valarray.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -31,4 +31,6 @@ int main()
         for (std::size_t i = 0; i < v3.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/or_valarray_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/or_valarray_valarray.pass.cpp
index ef2b165098041ecc47164aaa1385ad3a402cd374..f62cb4f8cc2fcc3d712df86b00c83ce71bf13a55 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/or_valarray_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/or_valarray_valarray.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -34,4 +34,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/or_valarray_value.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/or_valarray_value.pass.cpp
index 60f14f2bb564c54bcc7d4834054c5b0376be2bd8..df73f85e398bfb30119fa9c29ec43ad6a8744956 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/or_valarray_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/or_valarray_value.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -42,4 +42,6 @@ int main()
         for (std::size_t i = 0; i < v1.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/or_value_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/or_value_valarray.pass.cpp
index 0d9a3124e6c39fba30c81d9f836b1a252957f83c..3798acc67d9513e1f8c908d162882fda3d4256ac 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/or_value_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.comparison/or_value_valarray.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -42,4 +42,6 @@ int main()
         for (std::size_t i = 0; i < v3.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.special/swap.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.special/swap.pass.cpp
index 4783508372190de9726068bdc28d9048b2a69a30..2200ddfe015ae800af082c0eb7ff2528758c4d1c 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.special/swap.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.special/swap.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -84,4 +84,6 @@ int main()
         for (std::size_t i = 0; i < v2.size(); ++i)
             assert(v2[i] == v1_save[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/abs_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/abs_valarray.pass.cpp
index ff5c7d89a7a76ba7986dc9a807bafb00e095a30e..d721c8442634f7dee351f5887569c7f0ca20348a 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/abs_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/abs_valarray.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -31,4 +31,6 @@ int main()
         for (std::size_t i = 0; i < v3.size(); ++i)
             assert(v3[i] == a3[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/acos_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/acos_valarray.pass.cpp
index bee16abd7984e2e641311d3630752db7dfc118ee..18b5bcb5b6c2ac7b8ad2b6064d494ba37614584c 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/acos_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/acos_valarray.pass.cpp
@@ -31,7 +31,7 @@ bool is_about(double x, double y, int p)
     return a == o.str();
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -48,4 +48,6 @@ int main()
         for (std::size_t i = 0; i < v3.size(); ++i)
             assert(is_about(v3[i], a3[i], 10));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/asin_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/asin_valarray.pass.cpp
index 4cecd8cace16f24d75e4f8dd00a7d1ef25f419a9..9401200e5c7b15fd5e54850b31f2becadc1507c2 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/asin_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/asin_valarray.pass.cpp
@@ -31,7 +31,7 @@ bool is_about(double x, double y, int p)
     return a == o.str();
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -48,4 +48,6 @@ int main()
         for (std::size_t i = 0; i < v3.size(); ++i)
             assert(is_about(v3[i], a3[i], 10));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/atan2_valarray_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/atan2_valarray_valarray.pass.cpp
index 7e81821dd449dd740061c852c0aa807e7fd11671..fcbd63b8317b35903ccca6af209593cb7d5e041d 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/atan2_valarray_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/atan2_valarray_valarray.pass.cpp
@@ -31,7 +31,7 @@ bool is_about(double x, double y, int p)
     return a == o.str();
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -50,4 +50,6 @@ int main()
         for (std::size_t i = 0; i < v3.size(); ++i)
             assert(is_about(v3[i], a3[i], 10));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/atan2_valarray_value.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/atan2_valarray_value.pass.cpp
index 3ab73757778dcea81bba985fd6abde09ac82c2a3..59928d447ea7d00a39ea352cf56438c62c224eea 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/atan2_valarray_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/atan2_valarray_value.pass.cpp
@@ -31,7 +31,7 @@ bool is_about(double x, double y, int p)
     return a == o.str();
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -48,4 +48,6 @@ int main()
         for (std::size_t i = 0; i < v3.size(); ++i)
             assert(is_about(v3[i], a3[i], 10));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/atan2_value_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/atan2_value_valarray.pass.cpp
index 07e7894ae1490dfd9fbf2ca58b48cc07d7dbcb52..ed42627d1f911c2010b8c8a50f3548f29197f8be 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/atan2_value_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/atan2_value_valarray.pass.cpp
@@ -31,7 +31,7 @@ bool is_about(double x, double y, int p)
     return a == o.str();
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -48,4 +48,6 @@ int main()
         for (std::size_t i = 0; i < v3.size(); ++i)
             assert(is_about(v3[i], a3[i], 10));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/atan_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/atan_valarray.pass.cpp
index 567f568a9155b1ffa7b6a3ce3324ff2c9d812ada..7176b9343e535070533091fa063cc830b39a8a74 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/atan_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/atan_valarray.pass.cpp
@@ -31,7 +31,7 @@ bool is_about(double x, double y, int p)
     return a == o.str();
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -48,4 +48,6 @@ int main()
         for (std::size_t i = 0; i < v3.size(); ++i)
             assert(is_about(v3[i], a3[i], 10));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/cos_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/cos_valarray.pass.cpp
index 182b8bc3a9f5e13b80f63600c1bb736ee451a7cf..bc58e4af23cb24f5ba371960cbdc078e5ecf81cc 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/cos_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/cos_valarray.pass.cpp
@@ -31,7 +31,7 @@ bool is_about(double x, double y, int p)
     return a == o.str();
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -48,4 +48,6 @@ int main()
         for (std::size_t i = 0; i < v3.size(); ++i)
             assert(is_about(v3[i], a3[i], 10));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/cosh_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/cosh_valarray.pass.cpp
index fb0965bb3b23d760d09422c8cab52f5c8888ac7e..b453edd08c8c1cbb9cc733995894f9bdbc8909cf 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/cosh_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/cosh_valarray.pass.cpp
@@ -31,7 +31,7 @@ bool is_about(double x, double y, int p)
     return a == o.str();
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -48,4 +48,6 @@ int main()
         for (std::size_t i = 0; i < v3.size(); ++i)
             assert(is_about(v3[i], a3[i], 10));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/exp_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/exp_valarray.pass.cpp
index 3c19e3edfa16b8d4b402f166d07927c99aa56a3b..8e95f870410e27048f497c19b91724b0fc55393a 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/exp_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/exp_valarray.pass.cpp
@@ -31,7 +31,7 @@ bool is_about(double x, double y, int p)
     return a == o.str();
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -48,4 +48,6 @@ int main()
         for (std::size_t i = 0; i < v3.size(); ++i)
             assert(is_about(v3[i], a3[i], 10));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/log10_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/log10_valarray.pass.cpp
index 70ba211a82ad95ab1701927d4e46cc5139dcd6d3..39514ed6833feef18e2e8ec92a34b0b8094fdc78 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/log10_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/log10_valarray.pass.cpp
@@ -31,7 +31,7 @@ bool is_about(double x, double y, int p)
     return a == o.str();
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -48,4 +48,6 @@ int main()
         for (std::size_t i = 0; i < v3.size(); ++i)
             assert(is_about(v3[i], a3[i], 10));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/log_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/log_valarray.pass.cpp
index 3e616a062bb7a5c5e1b1849a73d6958c2d5ad326..050d58fa5991b8fb76ecfe96aeba397fd5ae7d99 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/log_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/log_valarray.pass.cpp
@@ -31,7 +31,7 @@ bool is_about(double x, double y, int p)
     return a == o.str();
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -48,4 +48,6 @@ int main()
         for (std::size_t i = 0; i < v3.size(); ++i)
             assert(is_about(v3[i], a3[i], 10));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/pow_valarray_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/pow_valarray_valarray.pass.cpp
index 096cd5d322e52daddbf46dfe1bbf342eeb1cc88d..93b8a14cbe69e1956d73bb7a5ea2ba1034f65c07 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/pow_valarray_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/pow_valarray_valarray.pass.cpp
@@ -31,7 +31,7 @@ bool is_about(double x, double y, int p)
     return a == o.str();
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -50,4 +50,6 @@ int main()
         for (std::size_t i = 0; i < v3.size(); ++i)
             assert(is_about(v3[i], a3[i], 10));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/pow_valarray_value.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/pow_valarray_value.pass.cpp
index 902c9f3216fc96670913def584d73a442721a18e..62c140c04da47cacde256aadd02070690d790b03 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/pow_valarray_value.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/pow_valarray_value.pass.cpp
@@ -31,7 +31,7 @@ bool is_about(double x, double y, int p)
     return a == o.str();
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -48,4 +48,6 @@ int main()
         for (std::size_t i = 0; i < v3.size(); ++i)
             assert(is_about(v3[i], a3[i], 10));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/pow_value_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/pow_value_valarray.pass.cpp
index 39449782330caeb015a3624a4c1bb33ce670e366..0c8a76b6dac36ef63d37c62069dfd8a60ad36cea 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/pow_value_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/pow_value_valarray.pass.cpp
@@ -31,7 +31,7 @@ bool is_about(double x, double y, int p)
     return a == o.str();
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -48,4 +48,6 @@ int main()
         for (std::size_t i = 0; i < v3.size(); ++i)
             assert(is_about(v3[i], a3[i], 10));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/sin_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/sin_valarray.pass.cpp
index 2cf38b88bda16c6df223dc07843164f1a398b4b3..92d6f4492a5b993bb6dbb3dd460dfeedca774eb8 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/sin_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/sin_valarray.pass.cpp
@@ -31,7 +31,7 @@ bool is_about(double x, double y, int p)
     return a == o.str();
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -48,4 +48,6 @@ int main()
         for (std::size_t i = 0; i < v3.size(); ++i)
             assert(is_about(v3[i], a3[i], 10));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/sinh_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/sinh_valarray.pass.cpp
index fa591d0c6e3944794477a0db535bd3c6f5fda724..190c212ac8bcaa7cea92333d75bef7314409bd2c 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/sinh_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/sinh_valarray.pass.cpp
@@ -31,7 +31,7 @@ bool is_about(double x, double y, int p)
     return a == o.str();
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -48,4 +48,6 @@ int main()
         for (std::size_t i = 0; i < v3.size(); ++i)
             assert(is_about(v3[i], a3[i], 10));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/sqrt_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/sqrt_valarray.pass.cpp
index eb40e61b314be63fa16c3fe1a4e35fe7142f0f27..805bde633e3e18f59cf4f24ffc8aaed7336ac6df 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/sqrt_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/sqrt_valarray.pass.cpp
@@ -31,7 +31,7 @@ bool is_about(double x, double y, int p)
     return a == o.str();
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -48,4 +48,6 @@ int main()
         for (std::size_t i = 0; i < v3.size(); ++i)
             assert(is_about(v3[i], a3[i], 10));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/tan_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/tan_valarray.pass.cpp
index 6395ee55079fc182d70d1e38da7af69665976209..4f5b69d0884bda5a7923c9641670025d8e943584 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/tan_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/tan_valarray.pass.cpp
@@ -31,7 +31,7 @@ bool is_about(double x, double y, int p)
     return a == o.str();
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -48,4 +48,6 @@ int main()
         for (std::size_t i = 0; i < v3.size(); ++i)
             assert(is_about(v3[i], a3[i], 10));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/tanh_valarray.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/tanh_valarray.pass.cpp
index 10e0a22be2cb0c2ea401439d20b7d2985a2094fa..c63696a8380571f402ef0e7f430bfebe805fa100 100644
--- a/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/tanh_valarray.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.nonmembers/valarray.transcend/tanh_valarray.pass.cpp
@@ -31,7 +31,7 @@ bool is_about(double x, double y, int p)
     return a == o.str();
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef double T;
@@ -48,4 +48,6 @@ int main()
         for (std::size_t i = 0; i < v3.size(); ++i)
             assert(is_about(v3[i], a3[i], 10));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.range/begin_const.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.range/begin_const.pass.cpp
index db39ab4a1cd88008c4a3383a8dbd50d708ca3ce1..35e5e4206aa73559394dfce1dbd1d5a07da99770 100644
--- a/libcxx/test/std/numerics/numarray/valarray.range/begin_const.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.range/begin_const.pass.cpp
@@ -17,7 +17,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -26,4 +26,6 @@ int main()
         const std::valarray<T> v(a, N);
         assert(v[0] == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.range/begin_non_const.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.range/begin_non_const.pass.cpp
index fb4013dee6a3257e1a7f895eb73ef1f4adb3365a..e0d8e71da260b74f09f02a859749d9070dd33e6c 100644
--- a/libcxx/test/std/numerics/numarray/valarray.range/begin_non_const.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.range/begin_non_const.pass.cpp
@@ -17,7 +17,7 @@
 #include <valarray>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -27,4 +27,6 @@ int main()
         *begin(v) = 10;
         assert(v[0] == 10);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.range/end_const.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.range/end_const.pass.cpp
index 113216ad067a057fe97660297890e2db01f64544..d1424d3f0c1707f4d58973adf7c9b9192118c379 100644
--- a/libcxx/test/std/numerics/numarray/valarray.range/end_const.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.range/end_const.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -28,4 +28,6 @@ int main()
         assert(v[v.size()-1] == 5);
         assert(static_cast<std::size_t>(end(v) - begin(v)) == v.size());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.range/end_non_const.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.range/end_non_const.pass.cpp
index c5d54729aaa8021a1f118f69bcf37b2269d953ff..5e1cbd4a80510978a2b621edd16d58904cc23827 100644
--- a/libcxx/test/std/numerics/numarray/valarray.range/end_non_const.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.range/end_non_const.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -29,4 +29,6 @@ int main()
         assert(v[v.size()-1] == 10);
         assert(static_cast<std::size_t>(end(v) - begin(v)) == v.size());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numarray/valarray.syn/nothing_to_do.pass.cpp b/libcxx/test/std/numerics/numarray/valarray.syn/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/numerics/numarray/valarray.syn/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/numerics/numarray/valarray.syn/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/accumulate/accumulate.pass.cpp b/libcxx/test/std/numerics/numeric.ops/accumulate/accumulate.pass.cpp
index 2a14a7d8e5e8211bd1c149cc85cb5973d0b08c6e..80a048d07ed933fe7e0163c23defde2f5bab9916 100644
--- a/libcxx/test/std/numerics/numeric.ops/accumulate/accumulate.pass.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/accumulate/accumulate.pass.cpp
@@ -42,11 +42,13 @@ test()
     test(Iter(ia), Iter(ia+sa), 10, 31);
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*> >();
     test<forward_iterator<const int*> >();
     test<bidirectional_iterator<const int*> >();
     test<random_access_iterator<const int*> >();
     test<const int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/accumulate/accumulate_op.pass.cpp b/libcxx/test/std/numerics/numeric.ops/accumulate/accumulate_op.pass.cpp
index a6dc04b2dfaedee98968c8e68a23c68baa546e68..c7a55b971e6975b9c89d8dedb837b15bf28dc3a2 100644
--- a/libcxx/test/std/numerics/numeric.ops/accumulate/accumulate_op.pass.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/accumulate/accumulate_op.pass.cpp
@@ -44,11 +44,13 @@ test()
     test(Iter(ia), Iter(ia+sa), 10, 7200);
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*> >();
     test<forward_iterator<const int*> >();
     test<bidirectional_iterator<const int*> >();
     test<random_access_iterator<const int*> >();
     test<const int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/adjacent.difference/adjacent_difference.pass.cpp b/libcxx/test/std/numerics/numeric.ops/adjacent.difference/adjacent_difference.pass.cpp
index ac0b177417381cb5f54625a9b72de7c2b1db2861..3e043e5cb8fe276e7ab377850edf6ecb0847fffb 100644
--- a/libcxx/test/std/numerics/numeric.ops/adjacent.difference/adjacent_difference.pass.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/adjacent.difference/adjacent_difference.pass.cpp
@@ -75,7 +75,7 @@ public:
 
 #endif
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, output_iterator<int*> >();
     test<input_iterator<const int*>, forward_iterator<int*> >();
@@ -112,4 +112,6 @@ int main()
     Y y[3] = {Y(1), Y(2), Y(3)};
     std::adjacent_difference(x, x+3, y);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/adjacent.difference/adjacent_difference_op.pass.cpp b/libcxx/test/std/numerics/numeric.ops/adjacent.difference/adjacent_difference_op.pass.cpp
index 967ec2ea345c2f12d2b1e60dc77269c7d0f4a977..9a10105d04909f740f96c29806e52aeba08e6246 100644
--- a/libcxx/test/std/numerics/numeric.ops/adjacent.difference/adjacent_difference_op.pass.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/adjacent.difference/adjacent_difference_op.pass.cpp
@@ -78,7 +78,7 @@ public:
 #endif
 
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, output_iterator<int*> >();
     test<input_iterator<const int*>, forward_iterator<int*> >();
@@ -115,4 +115,6 @@ int main()
     Y y[3] = {Y(1), Y(2), Y(3)};
     std::adjacent_difference(x, x+3, y, std::minus<X>());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/exclusive.scan/exclusive_scan.pass.cpp b/libcxx/test/std/numerics/numeric.ops/exclusive.scan/exclusive_scan.pass.cpp
index 5568e0d805cc0ef8cf140417bfa02043bf448be8..447ceb61ed8f4c255082ba2d453a8b0040cdcccb 100644
--- a/libcxx/test/std/numerics/numeric.ops/exclusive.scan/exclusive_scan.pass.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/exclusive.scan/exclusive_scan.pass.cpp
@@ -85,7 +85,7 @@ void basic_tests()
 
 }
 
-int main()
+int main(int, char**)
 {
     basic_tests();
 
@@ -96,4 +96,6 @@ int main()
     test<random_access_iterator<const int*> >();
     test<const int*>();
     test<      int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/exclusive.scan/exclusive_scan_init_op.pass.cpp b/libcxx/test/std/numerics/numeric.ops/exclusive.scan/exclusive_scan_init_op.pass.cpp
index 78c8325e2192d9e549f4dfc0a08c288b35ca6421..46cb0800b7b5b3f68fe0cb38c3acdabc18146ff0 100644
--- a/libcxx/test/std/numerics/numeric.ops/exclusive.scan/exclusive_scan_init_op.pass.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/exclusive.scan/exclusive_scan_init_op.pass.cpp
@@ -59,7 +59,7 @@ test()
         }
 }
 
-int main()
+int main(int, char**)
 {
 //  All the iterator categories
     test<input_iterator        <const int*> >();
@@ -85,4 +85,6 @@ int main()
         assert(res[i] == j);
     }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/inclusive.scan/inclusive_scan.pass.cpp b/libcxx/test/std/numerics/numeric.ops/inclusive.scan/inclusive_scan.pass.cpp
index b02ce5408bffa22dd63e44be7b13f7fc7c653a70..0ab019c5e000f6ad95b8737ecf9cb9161a675199 100644
--- a/libcxx/test/std/numerics/numeric.ops/inclusive.scan/inclusive_scan.pass.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/inclusive.scan/inclusive_scan.pass.cpp
@@ -90,7 +90,7 @@ void basic_tests()
     }
 }
 
-int main()
+int main(int, char**)
 {
     basic_tests();
 
@@ -101,4 +101,6 @@ int main()
     test<random_access_iterator<const int*> >();
     test<const int*>();
     test<      int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/inclusive.scan/inclusive_scan_op.pass.cpp b/libcxx/test/std/numerics/numeric.ops/inclusive.scan/inclusive_scan_op.pass.cpp
index 07561175b1035e055e28a81ff4ca390d96929f0f..88633ac84ede242cc5b8f716f154f9480d5404ce 100644
--- a/libcxx/test/std/numerics/numeric.ops/inclusive.scan/inclusive_scan_op.pass.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/inclusive.scan/inclusive_scan_op.pass.cpp
@@ -97,7 +97,7 @@ void basic_tests()
 }
 
 
-int main()
+int main(int, char**)
 {
 
     basic_tests();
@@ -110,4 +110,6 @@ int main()
 //     test<const int*>();
 //     test<      int*>();
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/inclusive.scan/inclusive_scan_op_init.pass.cpp b/libcxx/test/std/numerics/numeric.ops/inclusive.scan/inclusive_scan_op_init.pass.cpp
index 06a1874540a0da2946899f0200eaa869d3f0ffa7..c6e691aeeb8278bec7584b32d9d967fd66eb56a5 100644
--- a/libcxx/test/std/numerics/numeric.ops/inclusive.scan/inclusive_scan_op_init.pass.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/inclusive.scan/inclusive_scan_op_init.pass.cpp
@@ -113,7 +113,7 @@ void basic_tests()
 }
 
 
-int main()
+int main(int, char**)
 {
 
     basic_tests();
@@ -126,4 +126,6 @@ int main()
     test<const int*>();
     test<      int*>();
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/inner.product/inner_product.pass.cpp b/libcxx/test/std/numerics/numeric.ops/inner.product/inner_product.pass.cpp
index fec9182b128e365ec8088150a807dbf401861f34..fa5c1e8341a7e21182e76a7ad005740cfa2f843a 100644
--- a/libcxx/test/std/numerics/numeric.ops/inner.product/inner_product.pass.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/inner.product/inner_product.pass.cpp
@@ -47,7 +47,7 @@ test()
     test(Iter1(a), Iter1(a+sa), Iter2(b), 10, 66);
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, input_iterator<const int*> >();
     test<input_iterator<const int*>, forward_iterator<const int*> >();
@@ -78,4 +78,6 @@ int main()
     test<const int*, bidirectional_iterator<const int*> >();
     test<const int*, random_access_iterator<const int*> >();
     test<const int*, const int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/inner.product/inner_product_comp.pass.cpp b/libcxx/test/std/numerics/numeric.ops/inner.product/inner_product_comp.pass.cpp
index d0d152db1ae7e4ca01ced8ce6664400f1985be8e..e42e3cea9154dff676b40b574eab18a683145568 100644
--- a/libcxx/test/std/numerics/numeric.ops/inner.product/inner_product_comp.pass.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/inner.product/inner_product_comp.pass.cpp
@@ -50,7 +50,7 @@ test()
     test(Iter1(a), Iter1(a+sa), Iter2(b), 10, 1176490);
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, input_iterator<const int*> >();
     test<input_iterator<const int*>, forward_iterator<const int*> >();
@@ -81,4 +81,6 @@ int main()
     test<const int*, bidirectional_iterator<const int*> >();
     test<const int*, random_access_iterator<const int*> >();
     test<const int*, const int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/numeric.iota/iota.pass.cpp b/libcxx/test/std/numerics/numeric.ops/numeric.iota/iota.pass.cpp
index 3128674253db37e572f9c19c1aa0a07e4fb63598..2c1c08e8b540a54f10f1fe410b02971dbf2877f6 100644
--- a/libcxx/test/std/numerics/numeric.ops/numeric.iota/iota.pass.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/numeric.iota/iota.pass.cpp
@@ -28,10 +28,12 @@ test()
         assert(ia[i] == ir[i]);
 }
 
-int main()
+int main(int, char**)
 {
     test<forward_iterator<int*> >();
     test<bidirectional_iterator<int*> >();
     test<random_access_iterator<int*> >();
     test<int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.bool1.fail.cpp b/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.bool1.fail.cpp
index 70173d08be69d7760edd34c0fb4d6dcfcb8a3a7e..1c56a670731b224ba2dd03c9d9e04386b2b6d7bd 100644
--- a/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.bool1.fail.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.bool1.fail.cpp
@@ -18,7 +18,9 @@
 #include <numeric>
 
 
-int main()
+int main(int, char**)
 {
     std::gcd(false, 4);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.bool2.fail.cpp b/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.bool2.fail.cpp
index 106434d9726268d2cd974534c22f7aa0e266f349..9390e50f1e783037e98dea5d67244028c12aa171 100644
--- a/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.bool2.fail.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.bool2.fail.cpp
@@ -18,7 +18,9 @@
 #include <numeric>
 
 
-int main()
+int main(int, char**)
 {
     std::gcd(2, true);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.bool3.fail.cpp b/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.bool3.fail.cpp
index 138bdd6db851bde04c441e87ad1abacd8bd09c9d..2aceb285bfe059480dcf2a81427c649323673f72 100644
--- a/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.bool3.fail.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.bool3.fail.cpp
@@ -18,7 +18,9 @@
 #include <numeric>
 
 
-int main()
+int main(int, char**)
 {
     std::gcd<volatile bool, int>(false, 4);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.bool4.fail.cpp b/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.bool4.fail.cpp
index 8e8e7559320ca330b01af7c4891cf19f13dedffd..234a4d7cefa466b6abd55bc221e7846d34603fc0 100644
--- a/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.bool4.fail.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.bool4.fail.cpp
@@ -18,7 +18,9 @@
 #include <numeric>
 
 
-int main()
+int main(int, char**)
 {
     std::gcd<int, const bool>(2, true);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.not_integral1.fail.cpp b/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.not_integral1.fail.cpp
index 7bcf29d13c27172c8ab7b162ca4de0b20f26de32..1aeb5249fff7a9fb76dd873eb211c0322803d8c4 100644
--- a/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.not_integral1.fail.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.not_integral1.fail.cpp
@@ -18,7 +18,9 @@
 #include <numeric>
 
 
-int main()
+int main(int, char**)
 {
     std::gcd(2.0, 4);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.not_integral2.fail.cpp b/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.not_integral2.fail.cpp
index aceb0ff63a9b825c1d522bda697ba22b4fe65fb1..89079181b514ae5519f4748e3f4e72769ed1f136 100644
--- a/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.not_integral2.fail.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.not_integral2.fail.cpp
@@ -18,7 +18,9 @@
 #include <numeric>
 
 
-int main()
+int main(int, char**)
 {
     std::gcd(4, 6.0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.pass.cpp b/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.pass.cpp
index 83a90b984c53173c7dca5a2d46f02be850928d73..bba3780bdc820071d684d7fa7d85aacabcc03654 100644
--- a/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.pass.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.pass.cpp
@@ -91,7 +91,7 @@ constexpr bool do_test(int = 0)
     return accumulate;
 }
 
-int main()
+int main(int, char**)
 {
     auto non_cce = std::rand(); // a value that can't possibly be constexpr
 
@@ -141,4 +141,6 @@ int main()
     static_assert(std::is_same_v<decltype(res), std::int64_t>, "");
     assert(res == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.bool1.fail.cpp b/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.bool1.fail.cpp
index 43fc1f5bfa59d0ca4cbd96ea6cdfa018c076ba41..ab199d7a8e53cd899b4822a514ad53013a84bcee 100644
--- a/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.bool1.fail.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.bool1.fail.cpp
@@ -18,7 +18,9 @@
 #include <numeric>
 
 
-int main()
+int main(int, char**)
 {
     std::lcm(false, 4);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.bool2.fail.cpp b/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.bool2.fail.cpp
index b9e1128dc9b967bcd8365a33fb83c2ca5f46201e..68bfd1d21718550e9a4e7ce20b48f09a01482290 100644
--- a/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.bool2.fail.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.bool2.fail.cpp
@@ -18,7 +18,9 @@
 #include <numeric>
 
 
-int main()
+int main(int, char**)
 {
     std::lcm(2, true);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.bool3.fail.cpp b/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.bool3.fail.cpp
index 763b65f99f67b9ff0bbf7bd83422d1d1eb937541..4f4042267eb6cd4c31ea8093df88938157451726 100644
--- a/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.bool3.fail.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.bool3.fail.cpp
@@ -18,7 +18,9 @@
 #include <numeric>
 
 
-int main()
+int main(int, char**)
 {
     std::lcm<volatile bool, int>(false, 4);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.bool4.fail.cpp b/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.bool4.fail.cpp
index dd7c43a41f7f55654af9fc60afb478fc44d17df1..2cdbcefdc2dbf0f4a114b0f801584e39948d1fad 100644
--- a/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.bool4.fail.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.bool4.fail.cpp
@@ -18,7 +18,9 @@
 #include <numeric>
 
 
-int main()
+int main(int, char**)
 {
     std::lcm<int, const bool>(2, true);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.not_integral1.fail.cpp b/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.not_integral1.fail.cpp
index 81f25887e5a6c9b23a621db6e33381863f0e41bf..968034b0228ebc8a2dcad1b34210934eb4270bcc 100644
--- a/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.not_integral1.fail.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.not_integral1.fail.cpp
@@ -18,7 +18,9 @@
 #include <numeric>
 
 
-int main()
+int main(int, char**)
 {
     std::lcm(2.0, 4);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.not_integral2.fail.cpp b/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.not_integral2.fail.cpp
index ef039ca7984d7d49934838166864fc1284bd2d2f..ed2813f6a34d9f580caebeaad584f9d40c4d7e78 100644
--- a/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.not_integral2.fail.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.not_integral2.fail.cpp
@@ -18,7 +18,9 @@
 #include <numeric>
 
 
-int main()
+int main(int, char**)
 {
     std::lcm(4, 6.0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.pass.cpp b/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.pass.cpp
index a42303776b2d5e38db8f6753de2ce14ca13fc091..8a05670613453018985804a316d930f453c59d5a 100644
--- a/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.pass.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/numeric.ops.lcm/lcm.pass.cpp
@@ -90,7 +90,7 @@ constexpr bool do_test(int = 0)
     return accumulate;
 }
 
-int main()
+int main(int, char**)
 {
     auto non_cce = std::rand(); // a value that can't possibly be constexpr
 
@@ -141,4 +141,6 @@ int main()
     static_assert(std::is_same_v<decltype(res1), std::int64_t>, "");
     assert(res1 == 1324997410816LL);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/partial.sum/partial_sum.pass.cpp b/libcxx/test/std/numerics/numeric.ops/partial.sum/partial_sum.pass.cpp
index 90a74e22f5efe3ee526148157b332a92e45ac123..4ea410712ca6cb6c177d075259af6e15c72784e0 100644
--- a/libcxx/test/std/numerics/numeric.ops/partial.sum/partial_sum.pass.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/partial.sum/partial_sum.pass.cpp
@@ -35,7 +35,7 @@ test()
         assert(ib[i] == ir[i]);
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, output_iterator<int*> >();
     test<input_iterator<const int*>, forward_iterator<int*> >();
@@ -66,4 +66,6 @@ int main()
     test<const int*, bidirectional_iterator<int*> >();
     test<const int*, random_access_iterator<int*> >();
     test<const int*, int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/partial.sum/partial_sum_op.pass.cpp b/libcxx/test/std/numerics/numeric.ops/partial.sum/partial_sum_op.pass.cpp
index eadcd5a3a1e8eac81ba4ac5cdb0dc598d75d292f..ab51b5b5b242566628e5a06f21d10ec5a16fee53 100644
--- a/libcxx/test/std/numerics/numeric.ops/partial.sum/partial_sum_op.pass.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/partial.sum/partial_sum_op.pass.cpp
@@ -37,7 +37,7 @@ test()
         assert(ib[i] == ir[i]);
 }
 
-int main()
+int main(int, char**)
 {
     test<input_iterator<const int*>, output_iterator<int*> >();
     test<input_iterator<const int*>, forward_iterator<int*> >();
@@ -68,4 +68,6 @@ int main()
     test<const int*, bidirectional_iterator<int*> >();
     test<const int*, random_access_iterator<int*> >();
     test<const int*, int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/reduce/reduce.pass.cpp b/libcxx/test/std/numerics/numeric.ops/reduce/reduce.pass.cpp
index ebdaaac91e0a6837abe6835bd1133c8c8a8d475e..031a12d290b0e1168031b9d39cf48f310019db2e 100644
--- a/libcxx/test/std/numerics/numeric.ops/reduce/reduce.pass.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/reduce/reduce.pass.cpp
@@ -46,7 +46,7 @@ void test_return_type()
     static_assert( std::is_same_v<T, decltype(std::reduce(p, p))> );
 }
 
-int main()
+int main(int, char**)
 {
     test_return_type<char>();
     test_return_type<int>();
@@ -59,4 +59,6 @@ int main()
     test<bidirectional_iterator<const int*> >();
     test<random_access_iterator<const int*> >();
     test<const int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/reduce/reduce_init.pass.cpp b/libcxx/test/std/numerics/numeric.ops/reduce/reduce_init.pass.cpp
index 22b5a7239c4ac528eaf6a97fffe831de5281d63a..19c6b7d5fc8d26be61dbeb53486ff0ff489e0ada 100644
--- a/libcxx/test/std/numerics/numeric.ops/reduce/reduce_init.pass.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/reduce/reduce_init.pass.cpp
@@ -48,7 +48,7 @@ void test_return_type()
     static_assert( std::is_same_v<Init, decltype(std::reduce(p, p, Init{}))> );
 }
 
-int main()
+int main(int, char**)
 {
     test_return_type<char, int>();
     test_return_type<int, int>();
@@ -63,4 +63,6 @@ int main()
     test<bidirectional_iterator<const int*> >();
     test<random_access_iterator<const int*> >();
     test<const int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/reduce/reduce_init_op.pass.cpp b/libcxx/test/std/numerics/numeric.ops/reduce/reduce_init_op.pass.cpp
index 7c26921716af1a956481aac31deb25fabfcfb5e3..adcf92879683449c7f357392d30c599a02c4ff42 100644
--- a/libcxx/test/std/numerics/numeric.ops/reduce/reduce_init_op.pass.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/reduce/reduce_init_op.pass.cpp
@@ -48,7 +48,7 @@ void test_return_type()
     static_assert( std::is_same_v<Init, decltype(std::reduce(p, p, Init{}, std::plus<>()))>, "" );
 }
 
-int main()
+int main(int, char**)
 {
     test_return_type<char, int>();
     test_return_type<int, int>();
@@ -70,4 +70,6 @@ int main()
     unsigned res = std::reduce(v.begin(), v.end(), 1U, std::multiplies<>());
     assert(res == 40320);       // 8! will not fit into a char
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/transform.exclusive.scan/transform_exclusive_scan_init_bop_uop.pass.cpp b/libcxx/test/std/numerics/numeric.ops/transform.exclusive.scan/transform_exclusive_scan_init_bop_uop.pass.cpp
index dc9412ec1f501d4d7b4b55e71485d1ba111aed01..528802cb4bfee0e8d9d88fb0c28c69fc6e9393df 100644
--- a/libcxx/test/std/numerics/numeric.ops/transform.exclusive.scan/transform_exclusive_scan_init_bop_uop.pass.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/transform.exclusive.scan/transform_exclusive_scan_init_bop_uop.pass.cpp
@@ -139,7 +139,7 @@ void basic_tests()
     }
 }
 
-int main()
+int main(int, char**)
 {
     basic_tests();
 
@@ -150,4 +150,6 @@ int main()
     test<random_access_iterator<const int*> >();
     test<const int*>();
     test<      int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/transform.inclusive.scan/transform_inclusive_scan_bop_uop.pass.cpp b/libcxx/test/std/numerics/numeric.ops/transform.inclusive.scan/transform_inclusive_scan_bop_uop.pass.cpp
index 412c4b2922c8c62cbeac64827ee85669b79def93..f7a32131719f3ec10f1f60d8dd026d65807f21fe 100644
--- a/libcxx/test/std/numerics/numeric.ops/transform.inclusive.scan/transform_inclusive_scan_bop_uop.pass.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/transform.inclusive.scan/transform_inclusive_scan_bop_uop.pass.cpp
@@ -113,7 +113,7 @@ void basic_tests()
     }
 }
 
-int main()
+int main(int, char**)
 {
     basic_tests();
 
@@ -124,4 +124,6 @@ int main()
     test<random_access_iterator<const int*> >();
     test<const int*>();
     test<      int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/transform.inclusive.scan/transform_inclusive_scan_bop_uop_init.pass.cpp b/libcxx/test/std/numerics/numeric.ops/transform.inclusive.scan/transform_inclusive_scan_bop_uop_init.pass.cpp
index d29131bd1a5c1066f50616b6c67b4e9fceaf713b..56e5bc6e75c87db30970346b197fb37db4dc7d3d 100644
--- a/libcxx/test/std/numerics/numeric.ops/transform.inclusive.scan/transform_inclusive_scan_bop_uop_init.pass.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/transform.inclusive.scan/transform_inclusive_scan_bop_uop_init.pass.cpp
@@ -139,7 +139,7 @@ void basic_tests()
     }
 }
 
-int main()
+int main(int, char**)
 {
     basic_tests();
 
@@ -150,4 +150,6 @@ int main()
     test<random_access_iterator<const int*> >();
     test<const int*>();
     test<      int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/transform.reduce/transform_reduce_iter_iter_init_bop_uop.pass.cpp b/libcxx/test/std/numerics/numeric.ops/transform.reduce/transform_reduce_iter_iter_init_bop_uop.pass.cpp
index 541fbb76f9fa70ac178a1f476295643becbc6e4c..38071531b22ac2017fd982da00943626c51ef4b8 100644
--- a/libcxx/test/std/numerics/numeric.ops/transform.reduce/transform_reduce_iter_iter_init_bop_uop.pass.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/transform.reduce/transform_reduce_iter_iter_init_bop_uop.pass.cpp
@@ -91,7 +91,7 @@ void test_move_only_types()
         [](const MoveOnly& target) { return MoveOnly{target.get() * 10}; }).get());
 }
 
-int main()
+int main(int, char**)
 {
     test_return_type<char, int>();
     test_return_type<int, int>();
@@ -117,4 +117,6 @@ int main()
     }
 
     test_move_only_types();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/transform.reduce/transform_reduce_iter_iter_iter_init.pass.cpp b/libcxx/test/std/numerics/numeric.ops/transform.reduce/transform_reduce_iter_iter_iter_init.pass.cpp
index 8f846a8930eac49c619f1f1edde4edd374850c09..d74267c71fb31bbb0e3e7c19d36f9904528781df 100644
--- a/libcxx/test/std/numerics/numeric.ops/transform.reduce/transform_reduce_iter_iter_iter_init.pass.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/transform.reduce/transform_reduce_iter_iter_iter_init.pass.cpp
@@ -65,7 +65,7 @@ void test_move_only_types()
         std::transform_reduce(std::begin(ia), std::end(ia), std::begin(ib), MoveOnly{0}).get());
 }
 
-int main()
+int main(int, char**)
 {
     test_return_type<char, int>();
     test_return_type<int, int>();
@@ -103,4 +103,6 @@ int main()
     test<      int*,       unsigned int *>();
 
     test_move_only_types();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.ops/transform.reduce/transform_reduce_iter_iter_iter_init_op_op.pass.cpp b/libcxx/test/std/numerics/numeric.ops/transform.reduce/transform_reduce_iter_iter_iter_init_op_op.pass.cpp
index 586e7b180dbdec5cfbefaad1e6080a8f8b67a448..27bad12ce6191db26cfb2469926085170eecedf6 100644
--- a/libcxx/test/std/numerics/numeric.ops/transform.reduce/transform_reduce_iter_iter_iter_init_op_op.pass.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/transform.reduce/transform_reduce_iter_iter_iter_init_op_op.pass.cpp
@@ -69,7 +69,7 @@ void test_move_only_types()
         [](const MoveOnly& lhs, const MoveOnly& rhs) { return MoveOnly{lhs.get() * rhs.get()}; }).get());
 }
 
-int main()
+int main(int, char**)
 {
     test_return_type<char, int>();
     test_return_type<int, int>();
@@ -107,4 +107,6 @@ int main()
     test<      int*,       unsigned int *>();
 
     test_move_only_types();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numeric.requirements/nothing_to_do.pass.cpp b/libcxx/test/std/numerics/numeric.requirements/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/numerics/numeric.requirements/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/numerics/numeric.requirements/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/numerics.general/nothing_to_do.pass.cpp b/libcxx/test/std/numerics/numerics.general/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/numerics/numerics.general/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/numerics/numerics.general/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/nothing_to_do.pass.cpp b/libcxx/test/std/numerics/rand/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/numerics/rand/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/numerics/rand/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/nothing_to_do.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/assign.pass.cpp
index dbc038fc5bcadc1cabcc241d9cfc6f9222114733..5deb1d50cfa4107c2a2e72f929cd99aa1bdd1490 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/assign.pass.cpp
@@ -48,8 +48,10 @@ test2()
     assert(e1 == e2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/copy.pass.cpp
index 78bc6b2972a90e030bb6761d97d88440f1b11391..443f4f8d86c80a23329281e02567301be3fcf0ff 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/copy.pass.cpp
@@ -46,8 +46,10 @@ test2()
     assert(e1 == e2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/ctor_engine_copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/ctor_engine_copy.pass.cpp
index a0833fb4a725e8d10999a2428096daabaaf02b46..57f2bcc76a31f22d66dd41eb3c11650c55834e06 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/ctor_engine_copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/ctor_engine_copy.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::ranlux24_base Engine;
@@ -25,4 +25,6 @@ int main()
         Adaptor a(e);
         assert(a.base() == e);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/ctor_engine_move.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/ctor_engine_move.pass.cpp
index 5df116384d7ad3ac82532011a3f21068a1e51e0b..ade8e8d81cff0edd7f0d1375b359bae7acbc1846 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/ctor_engine_move.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/ctor_engine_move.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::ranlux24_base Engine;
@@ -26,4 +26,6 @@ int main()
         Adaptor a(std::move(e0));
         assert(a.base() == e);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/ctor_result_type.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/ctor_result_type.pass.cpp
index 4022917b9f01da8801d98d08f925d9f87a04d3ab..6fe0947631c904fbde2d64bb13890f8d00398cd7 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/ctor_result_type.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/ctor_result_type.pass.cpp
@@ -43,8 +43,10 @@ test2()
     assert(os.str() == a);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/ctor_sseq.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/ctor_sseq.pass.cpp
index c56bf4503ce459494bb18f88d9ccd0461e7aa84d..fe2d9fea312ca18a86a60a82d968e4ab3ea805f1 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/ctor_sseq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/ctor_sseq.pass.cpp
@@ -47,8 +47,10 @@ test2()
     assert(os.str() == a);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/default.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/default.pass.cpp
index 703dd3d7c9e53fe328a8d1ef71373d82e196c605..32af7046fdd08579a103ea5a4b5bb4a0233e1e8d 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/default.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/default.pass.cpp
@@ -34,8 +34,10 @@ test2()
     assert(e1() == 23459059301164ull);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/discard.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/discard.pass.cpp
index ca675b9ffba7fd6ab75d2ea679e391d4a4f4834d..a6f4d64e3343a3242f1a1f68f0b384b5bbe4fb27 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/discard.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/discard.pass.cpp
@@ -44,8 +44,10 @@ test2()
     assert(e1 == e2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/eval.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/eval.pass.cpp
index 33e0f73ee869d4e8519622833cfe7ae2ccca6b90..75f07aecae57cad432fd111f6382d33af3d77f5f 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/eval.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/eval.pass.cpp
@@ -34,8 +34,10 @@ test2()
     assert(e() == 276846226770426ull);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/io.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/io.pass.cpp
index ebfddfc371d887bc7b059ef28a5fd76bdeaede55..a9fbd7963e86a8233c21925a63f5a5a23da2b973 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/io.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/io.pass.cpp
@@ -55,8 +55,10 @@ test2()
     assert(e1 == e2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/result_type.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/result_type.pass.cpp
index 7df00d8e62980f6e0719cce02e3c6426aa0f126d..a18e09bd15f86cd594baae51798798dc9dfb518d 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/result_type.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/result_type.pass.cpp
@@ -34,8 +34,10 @@ test2()
         std::uint_fast64_t>::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/seed_result_type.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/seed_result_type.pass.cpp
index 0dff0790c6abaddc003f2c0c46558d3193e8e362..bfa93767eaaa8fbdf06dd3095959ac78f1b7a2ab 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/seed_result_type.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/seed_result_type.pass.cpp
@@ -42,8 +42,10 @@ test2()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/seed_sseq.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/seed_sseq.pass.cpp
index 738b306b256f2ed3d3d7ad72d4b41fff1b6ccf10..5506cffa1173542d687c9e9e73b4a72ead3e0264 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/seed_sseq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/seed_sseq.pass.cpp
@@ -40,8 +40,10 @@ test2()
     assert(e1 == e2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/values.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/values.pass.cpp
index fef9ab497373c6c7a72cb97dc4bd6c11930f199c..423a629e7f20ff75dea19f3e46300bd7577f5536 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/values.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.disc/values.pass.cpp
@@ -64,8 +64,10 @@ test2()
     where(E::used_block);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/assign.pass.cpp
index def8387e169e6229c47a1227b4df6b55e3189455..79205aacc73dbeb9a5769f078ad88511ce268605 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/assign.pass.cpp
@@ -48,8 +48,10 @@ test2()
     assert(e1 == e2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/copy.pass.cpp
index 179ffaf46d1903f8e05e1f35867d1a7775394e22..22e68626ede73527c6686b055e589f885f3950d2 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/copy.pass.cpp
@@ -46,8 +46,10 @@ test2()
     assert(e1 == e2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/ctor_engine_copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/ctor_engine_copy.pass.cpp
index c858600ccb1fedb68de4cbf91b19b6aa38e8354c..65fad3e2f834888f18faf50ff6b680c17af42793 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/ctor_engine_copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/ctor_engine_copy.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::mt19937 Engine;
@@ -25,4 +25,6 @@ int main()
         Adaptor a(e);
         assert(a.base() == e);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/ctor_engine_move.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/ctor_engine_move.pass.cpp
index 1ecf36c43c5e8e972f9815955f5d8155666f6555..f3b1d526fde2bcecc533d9a87c0d46cd255516dc 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/ctor_engine_move.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/ctor_engine_move.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::mt19937 Engine;
@@ -26,4 +26,6 @@ int main()
         Adaptor a(std::move(e0));
         assert(a.base() == e);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/ctor_result_type.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/ctor_result_type.pass.cpp
index 9fa1383a84186bb16a3eddada04aefe917878d9f..84817b16ea4df47212f70f388062701e606d3b9b 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/ctor_result_type.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/ctor_result_type.pass.cpp
@@ -43,8 +43,10 @@ test2()
     assert(os.str() == a);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/ctor_sseq.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/ctor_sseq.pass.cpp
index a179753a88e1fb72c7c8506a871b2d51c1050aee..d2792f98f05d935231d1b73e67f14faace6340db 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/ctor_sseq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/ctor_sseq.pass.cpp
@@ -47,8 +47,10 @@ test2()
     assert(os.str() == a);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/default.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/default.pass.cpp
index 422aaf936e35e5a8e29393e34295ef32e46a01dc..d7e72e3e72af0831f2183a3b4726b20e69e3661c 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/default.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/default.pass.cpp
@@ -34,8 +34,10 @@ test2()
     assert(e1() == 18223106896348967647ull);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/discard.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/discard.pass.cpp
index fa735c09e720cd5de7c305738c9d9bbfa61bd74a..8f292192361e0e857ed31fc77d823cfbf521d4ba 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/discard.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/discard.pass.cpp
@@ -44,8 +44,10 @@ test2()
     assert(e1 == e2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/eval.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/eval.pass.cpp
index 036dc1fbc9a16e9baacfdd0f5748a6bc0232bbdd..9d60eaba39aeab7b39cd10e1ec75b68f309677a2 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/eval.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/eval.pass.cpp
@@ -129,7 +129,7 @@ test8()
     assert(e() == 16470362623952407241ull);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
@@ -139,4 +139,6 @@ int main()
     test6();
     test7();
     test8();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/io.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/io.pass.cpp
index 0362cbfc23a20bb29f2c6015262063d26b5edda3..b1a73193c243b505f139149fd0386c6eaad0abb9 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/io.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/io.pass.cpp
@@ -55,8 +55,10 @@ test2()
     assert(e1 == e2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/result_type.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/result_type.pass.cpp
index ee47a38b9e38836ec65896c071af5e5e3f8db6e8..1b6fb87e347fcf4bc52e9a51fa1b522e60410ab8 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/result_type.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/result_type.pass.cpp
@@ -77,8 +77,10 @@ test2()
         unsigned long long>::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/seed_result_type.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/seed_result_type.pass.cpp
index 204c89739c552718459ad10915eff1238a5fb46c..8225044d778be57bb80578c3443062642f2c6c25 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/seed_result_type.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/seed_result_type.pass.cpp
@@ -42,8 +42,10 @@ test2()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/seed_sseq.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/seed_sseq.pass.cpp
index 5c1c34e728d74f2a31a4d262dbf60d12e5e46792..04374d00098f8819289b42dc27f450786cf9e4bf 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/seed_sseq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/seed_sseq.pass.cpp
@@ -40,8 +40,10 @@ test2()
     assert(e1 == e2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/values.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/values.pass.cpp
index 10d9f4d7554be24c3cbbbd9f38e1949f2dd7a280..be25ad1e2b046a84888b226cc7209fae3ebeaa66 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/values.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.ibits/values.pass.cpp
@@ -51,8 +51,10 @@ test2()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/assign.pass.cpp
index d3518432c38e11d97506fc53949a32653333fc7c..da08f58edb69b4b610ded5cf8923b9ea1b0807f9 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/assign.pass.cpp
@@ -32,7 +32,9 @@ test1()
     assert(e1 == e2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/copy.pass.cpp
index 7c4930879ae4c64176882c5e9f1e35265e7c53dc..5788371c36e65875f6d4130d99b029264f3567a0 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/copy.pass.cpp
@@ -31,7 +31,9 @@ test1()
     assert(e1 == e2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/ctor_engine_copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/ctor_engine_copy.pass.cpp
index 4bd8052627c0757a0fc125e1b53254561136efa4..0cc29d496dc8cf3fc02905a587c4001cf58a91c8 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/ctor_engine_copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/ctor_engine_copy.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::minstd_rand0 Engine;
@@ -29,4 +29,6 @@ int main()
 
         assert(a.base() == e);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/ctor_engine_move.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/ctor_engine_move.pass.cpp
index 6daa356a7dc19af8580ed447f5493805b55714d1..35474e6a0d6a5dff87ab160c278fce09b3745a64 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/ctor_engine_move.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/ctor_engine_move.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::minstd_rand0 Engine;
@@ -30,4 +30,6 @@ int main()
 
         assert(a.base() == e);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/ctor_result_type.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/ctor_result_type.pass.cpp
index ba0350fc5fb947fee300f4681f058426828e6e9d..5ca51e151e074004ba5fa3bb88095e94e3dce666 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/ctor_result_type.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/ctor_result_type.pass.cpp
@@ -69,7 +69,9 @@ test1()
     assert(os.str() == a);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/ctor_sseq.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/ctor_sseq.pass.cpp
index 3d3c06db2a2220a3d34f8332ad6b3532cd194dbe..136e7fe873f932b04dc98e0dbec94e0431358fcf 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/ctor_sseq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/ctor_sseq.pass.cpp
@@ -72,7 +72,9 @@ test1()
     assert(os.str() == a);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/default.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/default.pass.cpp
index 438c60790f07087b6145e638785fb3da3e791856..fff5cee2d0759b1ef6ccf40c159f7cc0f8e19dcd 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/default.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/default.pass.cpp
@@ -25,7 +25,9 @@ test1()
     assert(e1() == 152607844u);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/discard.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/discard.pass.cpp
index 3e98bf554d502143f769abde2449f5f8ae5c2714..1b86048c2e29d5724122c3a4dc37e34ced3539ab 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/discard.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/discard.pass.cpp
@@ -30,7 +30,9 @@ test1()
     assert(e1 == e2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/eval.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/eval.pass.cpp
index fa7056ca965f62659281efb951e71cbee439e5b4..4eecfea81b76e826fd051a6105a9369a8c150c7e 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/eval.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/eval.pass.cpp
@@ -86,9 +86,11 @@ test3()
     assert(e() == 500);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
     test3();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/io.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/io.pass.cpp
index 5d7a49a5f3bc24438ebc05e55042fc0ed331bb95..5d80b3afcbcd11f918e09317bdd84d05d8aa14f7 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/io.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/io.pass.cpp
@@ -41,7 +41,9 @@ test1()
     assert(e1 == e2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/result_type.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/result_type.pass.cpp
index 5ba0b5ed2f515bb4530d0b87a0562cf50efb1f7e..bcb08557c86a61621a0e936a3904cddb656f6320 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/result_type.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/result_type.pass.cpp
@@ -77,8 +77,10 @@ test2()
         unsigned long long>::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/seed_result_type.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/seed_result_type.pass.cpp
index 0d71f27e28a844031543c56cba8a712ff065ee46..24ccfbbf8e0b85b38e164835549aa7e9a4b3ea94 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/seed_result_type.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/seed_result_type.pass.cpp
@@ -29,7 +29,9 @@ test1()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/seed_sseq.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/seed_sseq.pass.cpp
index 0a5d386b1e5c4eb08aa8c941c12fbffa33aeeb86..8dfbcb00ee71c215b66625ffeb048a9805244143 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/seed_sseq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/seed_sseq.pass.cpp
@@ -28,7 +28,9 @@ test1()
     assert(e1 == e2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/values.pass.cpp b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/values.pass.cpp
index 8f9e52442a962f12f3f9ba03155d021d2155d6fa..d98fdf58a82d90d465272be33ad5057aceef0bed 100644
--- a/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/values.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.adapt/rand.adapt.shuf/values.pass.cpp
@@ -44,7 +44,9 @@ test1()
     where(E::table_size);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.device/ctor.pass.cpp b/libcxx/test/std/numerics/rand/rand.device/ctor.pass.cpp
index c9838f681448d45daa641525b4b09ce5f89d4f27..24e372795f05f9d7ce3e570448c2d50192f58ecb 100644
--- a/libcxx/test/std/numerics/rand/rand.device/ctor.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.device/ctor.pass.cpp
@@ -62,7 +62,7 @@ void check_random_device_invalid(const std::string &token) {
 }
 
 
-int main() {
+int main(int, char**) {
   {
     std::random_device r;
   }
@@ -99,4 +99,6 @@ int main() {
     std::random_device r;
   }
 #endif // !defined(_WIN32)
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.device/entropy.pass.cpp b/libcxx/test/std/numerics/rand/rand.device/entropy.pass.cpp
index 38197137743327ec215438a60a180326c2535024..539c238ba3a480fca3185529fe87d22ce7344ee2 100644
--- a/libcxx/test/std/numerics/rand/rand.device/entropy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.device/entropy.pass.cpp
@@ -15,9 +15,11 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::random_device r;
     double e = r.entropy();
     ((void)e); // Prevent unused warning
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.device/eval.pass.cpp b/libcxx/test/std/numerics/rand/rand.device/eval.pass.cpp
index b5b8aa11fd52681cc0e13c0076ed2f92a785ac9a..4b68282f77c00f171d98da888e77e245de997a47 100644
--- a/libcxx/test/std/numerics/rand/rand.device/eval.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.device/eval.pass.cpp
@@ -26,7 +26,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::random_device r;
@@ -45,4 +45,6 @@ int main()
     {
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/nothing_to_do.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/nothing_to_do.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/assign.pass.cpp
index bbd200d21c975249ce4f2ed485490ced11b96a7f..5ed93470d030afab6743487da9f186af3516f9c4 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/assign.pass.cpp
@@ -26,7 +26,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/copy.pass.cpp
index bf4291cec18f756d3af5f08e32b21952e344a82e..e3d866ad4616896854eea954df4c212aa98307ce 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/copy.pass.cpp
@@ -24,7 +24,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/ctor_double.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/ctor_double.pass.cpp
index 1d9a22d1e7ddf75914e0b260fbcad8f077a0e9ac..a8f76bb23249173dacb4c4c4748f8e3a5abd6b53 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/ctor_double.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/ctor_double.pass.cpp
@@ -15,7 +15,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::bernoulli_distribution D;
@@ -32,4 +32,6 @@ int main()
         D d(0.75);
         assert(d.p() == 0.75);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/ctor_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/ctor_param.pass.cpp
index 5543f4073223584b77b737d0272951ae7a4851b0..a568cb2b78a03ca1d596a793698fb407a9493805 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/ctor_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/ctor_param.pass.cpp
@@ -15,7 +15,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::bernoulli_distribution D;
@@ -24,4 +24,6 @@ int main()
         D d(p);
         assert(d.p() == 0.25);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/eq.pass.cpp
index faa683d4db8a6788a972528e0ac6754ca55c560a..24babc11829fa9868cd3d2a35ea0464037e94d89 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/eq.pass.cpp
@@ -18,7 +18,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::bernoulli_distribution D;
@@ -32,4 +32,6 @@ int main()
         D d2(.25);
         assert(d1 != d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/eval.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/eval.pass.cpp
index a16d5247508943ead203b6e505cdd15d2bfa13c3..e28c39099f88f9be614f413989969ef30fab6c39 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/eval.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/eval.pass.cpp
@@ -26,7 +26,7 @@ sqr(T x)
     return x * x;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::bernoulli_distribution D;
@@ -100,4 +100,6 @@ int main()
         assert(std::abs((skew - x_skew) / x_skew) < 0.01);
         assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.02);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/eval_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/eval_param.pass.cpp
index 6d83410d83eeef2e558535c6dbac3326fcc57da6..bf1d1174337cc03e100ced8d092235a25444ca39 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/eval_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/eval_param.pass.cpp
@@ -26,7 +26,7 @@ sqr(T x)
     return x * x;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::bernoulli_distribution D;
@@ -104,4 +104,6 @@ int main()
         assert(std::abs((skew - x_skew) / x_skew) < 0.01);
         assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.02);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/get_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/get_param.pass.cpp
index d24316d878c7eb9334e98e424e3c18603e2a5039..0e960d6acbadfaac2eca151e608ac787f2c1046d 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/get_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/get_param.pass.cpp
@@ -15,7 +15,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::bernoulli_distribution D;
@@ -24,4 +24,6 @@ int main()
         D d(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/io.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/io.pass.cpp
index 5107e900604dc489cdcca8a9756228a546b8ab7e..7c7829796d8f56de13bfa9eac5c74dfe4c5c2397 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/io.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/io.pass.cpp
@@ -24,7 +24,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::bernoulli_distribution D;
@@ -36,4 +36,6 @@ int main()
         is >> d2;
         assert(d1 == d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/max.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/max.pass.cpp
index acb1ada865b346bab0e77f1fcc41c47241ddd170..6f4ac7e3d47583cf254afbf4859278fbd34e8c6c 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/max.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/max.pass.cpp
@@ -15,11 +15,13 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::bernoulli_distribution D;
         D d(.25);
         assert(d.max() == true);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/min.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/min.pass.cpp
index 626f014b82c9005d8303ba59ed2967f3a4aa516a..8c369dbf82809037555082686d091d47515c15d5 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/min.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/min.pass.cpp
@@ -15,11 +15,13 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::bernoulli_distribution D;
         D d(.5);
         assert(d.min() == false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/param_assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/param_assign.pass.cpp
index f8ea5be59d11448b8864347409cee9e5f9f4a5e6..b4fcd04ecfc34b2e24db32c677c82817c0600150 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/param_assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/param_assign.pass.cpp
@@ -16,7 +16,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::bernoulli_distribution D;
@@ -26,4 +26,6 @@ int main()
         p = p0;
         assert(p.p() == .7);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/param_copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/param_copy.pass.cpp
index 91a8bacb7f86f0873f43e998e96befc0603d6a44..96ddd4bc4a9c5337e9f9d3f89f5af30f2f2e6f7a 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/param_copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/param_copy.pass.cpp
@@ -16,7 +16,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::bernoulli_distribution D;
@@ -25,4 +25,6 @@ int main()
         param_type p = p0;
         assert(p.p() == .125);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/param_ctor.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/param_ctor.pass.cpp
index cf1b7d391af50ee5635dee84c9fe8c714de3e9a0..612e6c6860ce3af4fb3aaed830e4281977ad3b1b 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/param_ctor.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/param_ctor.pass.cpp
@@ -16,7 +16,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::bernoulli_distribution D;
@@ -30,4 +30,6 @@ int main()
         param_type p(0.25);
         assert(p.p() == 0.25);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/param_eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/param_eq.pass.cpp
index b41a8f7785ac2cc8fde03300d315536d91a10599..cde5611ec37d8145f4028cd760a654b66144a803 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/param_eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/param_eq.pass.cpp
@@ -16,7 +16,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::bernoulli_distribution D;
@@ -32,4 +32,6 @@ int main()
         param_type p2(0.5);
         assert(p1 != p2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/param_types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/param_types.pass.cpp
index a8d6ba15fac8b6a63e764ceda9e2a3de26b9ce63..e1d9532f019ff631192793f0723be83cf3f24bf6 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/param_types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/param_types.pass.cpp
@@ -15,7 +15,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::bernoulli_distribution D;
@@ -23,4 +23,6 @@ int main()
         typedef param_type::distribution_type distribution_type;
         static_assert((std::is_same<D, distribution_type>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/set_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/set_param.pass.cpp
index 55af455973c2ad6c291f6b8d19f341d7446fb18a..03e3d8a8c78d6998177b074e6722c820a727dd7b 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/set_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/set_param.pass.cpp
@@ -15,7 +15,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::bernoulli_distribution D;
@@ -25,4 +25,6 @@ int main()
         d.param(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/types.pass.cpp
index 0be93b4b0d5e2e206d2df2d347853a53e3e6e792..539b809b068a8f7c26bec1313ae813f6125b871f 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bernoulli/types.pass.cpp
@@ -15,11 +15,13 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::bernoulli_distribution D;
         typedef D::result_type result_type;
         static_assert((std::is_same<result_type, bool>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/assign.pass.cpp
index 746a35fb54a5a811c1a89af3c6b4fc0e18e7eaae..e997198adb6e901b7523de48785d8af4428ef2cb 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/assign.pass.cpp
@@ -27,7 +27,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/copy.pass.cpp
index f66192938482b3e5cbe2a56c9b3958bb06239381..2c2b65c9441a8e4b4988c9129d8f39b7e44f535a 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/copy.pass.cpp
@@ -25,7 +25,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/ctor_int_double.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/ctor_int_double.pass.cpp
index f9ff59cd487fd8b627f1daa0f47954f25d0c6471..26a6e3a6622b8f47a1ae37567d1d4f82818f0b0f 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/ctor_int_double.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/ctor_int_double.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::binomial_distribution<> D;
@@ -36,4 +36,6 @@ int main()
         assert(d.t() == 3);
         assert(d.p() == 0.75);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/ctor_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/ctor_param.pass.cpp
index 569ec41c39ddcf7e5fbb49992dd14850e6ebc86e..fa69b91237ac8f4da59614cabc3792fa47932289 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/ctor_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/ctor_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::binomial_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         assert(d.t() == 5);
         assert(d.p() == 0.25);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/eq.pass.cpp
index b6c8aeb4a2470684516b51de71d39afa0caf74dd..dbe086ad4c7265a0c4803d41d9dd52dd8ae8a0d2 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/eq.pass.cpp
@@ -19,7 +19,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::binomial_distribution<> D;
@@ -39,4 +39,6 @@ int main()
         D d2(4, .25);
         assert(d1 != d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/eval.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/eval.pass.cpp
index 06f16c25777e88885bc1201f681331371edb8b77..fea71ccb876144f986e1b495b98a4029a8998d10 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/eval.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/eval.pass.cpp
@@ -506,7 +506,7 @@ test11()
 //    assert(kurtosis == x_kurtosis);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
@@ -519,4 +519,6 @@ int main()
     test9();
     test10();
     test11();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/eval_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/eval_param.pass.cpp
index 78a9e6e3b04bc3c4bccbe71e61fc4bca32af7200..cd4d006787817a314cc21cfd60f0dd3c4683b5a8 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/eval_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/eval_param.pass.cpp
@@ -28,7 +28,7 @@ sqr(T x)
     return x * x;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::binomial_distribution<> D;
@@ -156,4 +156,6 @@ int main()
         assert(std::abs((skew - x_skew) / x_skew) < 0.04);
         assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.3);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/get_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/get_param.pass.cpp
index 304a6b61a621b35995c764f66510dc5534afdf8f..a3ba48f55832e3fe17f0c25cd36d0b28ef9d8617 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/get_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/get_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::binomial_distribution<> D;
@@ -25,4 +25,6 @@ int main()
         D d(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/io.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/io.pass.cpp
index 90eeb394c5d0ee8e152b84c73602322fe2d55a88..cb272152a3bae23198c4b52767622f84f481e8fe 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/io.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/io.pass.cpp
@@ -25,7 +25,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::binomial_distribution<> D;
@@ -37,4 +37,6 @@ int main()
         is >> d2;
         assert(d1 == d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/max.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/max.pass.cpp
index 946e7ed93c3a452a556636595e3a570a4f513db3..c8ca662b630ece2ec37f72cdd92d54e64602f3ba 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/max.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/max.pass.cpp
@@ -16,11 +16,13 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::binomial_distribution<> D;
         D d(4, .25);
         assert(d.max() == 4);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/min.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/min.pass.cpp
index c6ac01110b453b416527cc79a0e3f254d3bd6903..ce793f67b7f53e764e8306751a72760114cf0dad 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/min.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/min.pass.cpp
@@ -16,11 +16,13 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::binomial_distribution<> D;
         D d(4, .5);
         assert(d.min() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/param_assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/param_assign.pass.cpp
index 24250bbcea9971e56290e5860a93cbbd7a53a1bd..069d6e440b85a841207496c8e77bd17672d5d80f 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/param_assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/param_assign.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::binomial_distribution<> D;
@@ -28,4 +28,6 @@ int main()
         assert(p.t() == 6);
         assert(p.p() == .7);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/param_copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/param_copy.pass.cpp
index 9445502ed02794b1e424e0c58c3001b7558fb088..f2b78e6d8f4d09ae0bb8decabbaa0e4eb396d7e8 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/param_copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/param_copy.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::binomial_distribution<> D;
@@ -27,4 +27,6 @@ int main()
         assert(p.t() == 10);
         assert(p.p() == .125);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/param_ctor.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/param_ctor.pass.cpp
index 2a7f92843798ca8db9ae8abe373e9e74eab9aecd..8ba09a681b2a57fdb63f9bd9fa08bda207182ac1 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/param_ctor.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/param_ctor.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::binomial_distribution<> D;
@@ -40,4 +40,6 @@ int main()
         assert(p.t() == 10);
         assert(p.p() == 0.25);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/param_eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/param_eq.pass.cpp
index 0e705adcf6f0f9c0b3dddb1daeec67594aa8c347..0ba4381ad185bdfb928750ccd0023bfe58e30803 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/param_eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/param_eq.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::binomial_distribution<> D;
@@ -33,4 +33,6 @@ int main()
         param_type p2(3, 0.5);
         assert(p1 != p2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/param_types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/param_types.pass.cpp
index 4e95286f37d23e54c5cdb30b7b6e437638c10397..ba94d412a9f397ac2a042ccfc88f7728fbe6d17b 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/param_types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/param_types.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::binomial_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         typedef param_type::distribution_type distribution_type;
         static_assert((std::is_same<D, distribution_type>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/set_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/set_param.pass.cpp
index 66f1d875d50975cc0035873ad100372a0921db3f..ec82a93ffc07de6b885a3a5f04e9ad6adf0643b0 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/set_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/set_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::binomial_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         d.param(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/types.pass.cpp
index 60f8114990677293f7763fcea4ed2ab1f1d7dc0e..c52681a1354ecd7e3498aa2784deb9d73a610343 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.bin/types.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::binomial_distribution<> D;
@@ -28,4 +28,6 @@ int main()
         typedef D::result_type result_type;
         static_assert((std::is_same<result_type, long>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/assign.pass.cpp
index 99d7a6dc138f85a34cdcd5e5c00dfccc3e72a808..ae49feb3e3d4b4855a9ffd2b83f5038a5b6b73c2 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/assign.pass.cpp
@@ -27,7 +27,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/copy.pass.cpp
index ea83185e5989b4f8496fcbe983a5071aafacf303..73ff6d68f9546cb9f58d355d51dc22b597ab4c41 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/copy.pass.cpp
@@ -25,7 +25,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/ctor_double.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/ctor_double.pass.cpp
index f099589c8a4da2c421dc44d36ce53af42bb647e1..1d4388e4dc34be451d161fb234519eed6224d264 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/ctor_double.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/ctor_double.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::geometric_distribution<> D;
@@ -28,4 +28,6 @@ int main()
         D d(0.75);
         assert(d.p() == 0.75);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/ctor_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/ctor_param.pass.cpp
index f682fb71c74a604dd3182b9f610549ff9f0335fe..3bcebc36f80ff2cea24f8a57e3c09dd8e14cb08f 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/ctor_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/ctor_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::geometric_distribution<> D;
@@ -25,4 +25,6 @@ int main()
         D d(p);
         assert(d.p() == 0.25);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/eq.pass.cpp
index aa358fe74e14e1873a6c7f01a4a66328fa5c74f9..47ea0f282476e3cb9267bfa0e2bc7a2c3016970b 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/eq.pass.cpp
@@ -19,7 +19,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::geometric_distribution<> D;
@@ -33,4 +33,6 @@ int main()
         D d2(.25);
         assert(d1 != d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/eval.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/eval.pass.cpp
index 4addb5e153bb8d53e1d9f0a58fdc6cd8e6c33ec5..46ec8812193633eb8b136e7105b706cbeecb6879 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/eval.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/eval.pass.cpp
@@ -286,7 +286,7 @@ test6()
     assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.02);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
@@ -294,4 +294,6 @@ int main()
     test4();
     test5();
     test6();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/eval_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/eval_param.pass.cpp
index a3194c4d1236f2e77a333bcc009c6b2b1ad972d6..825fa3f5c4d525d2caf604fd1cf6cf1deee0d7e0 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/eval_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/eval_param.pass.cpp
@@ -28,7 +28,7 @@ sqr(T x)
     return x * x;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::geometric_distribution<> D;
@@ -156,4 +156,6 @@ int main()
         assert(std::abs((skew - x_skew) / x_skew) < 0.01);
         assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.02);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/get_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/get_param.pass.cpp
index 2ef2406200e3739309ec69284e0523f812ae9030..35679a8627e6feabebc18e8c616997a7cb642bd8 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/get_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/get_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::geometric_distribution<> D;
@@ -25,4 +25,6 @@ int main()
         D d(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/io.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/io.pass.cpp
index fb419b4684938ffe68603b79051121f425b31a06..36de49f78cfc43ecb633155ffe86555364cce11b 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/io.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/io.pass.cpp
@@ -25,7 +25,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::geometric_distribution<> D;
@@ -37,4 +37,6 @@ int main()
         is >> d2;
         assert(d1 == d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/max.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/max.pass.cpp
index 00a3780edc6d21f4be82cbfedc3e5694f88ec5e6..9e785da2eed78acb9b740bca65be4605d32aa2db 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/max.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/max.pass.cpp
@@ -16,11 +16,13 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::geometric_distribution<> D;
         D d(.25);
         assert(d.max() == std::numeric_limits<int>::max());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/min.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/min.pass.cpp
index ab9e964f0af7753eac77eae683894f01805e8a77..63f69f25e2abb7bbd36b69f21c3336adeb7fb925 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/min.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/min.pass.cpp
@@ -16,11 +16,13 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::geometric_distribution<> D;
         D d(.5);
         assert(d.min() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/param_assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/param_assign.pass.cpp
index 0b6033d395b44cfc55a6c5e1394bee5c43185aa1..c88af2d68e1a008845ebbe6f5bcf26dff2d0ea76 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/param_assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/param_assign.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::geometric_distribution<> D;
@@ -27,4 +27,6 @@ int main()
         p = p0;
         assert(p.p() == .7);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/param_copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/param_copy.pass.cpp
index 92f9177673a02fb25399c50193d06595686b6778..117b98bc129725bd3737a87c6328d43f8648e2cb 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/param_copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/param_copy.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::geometric_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         param_type p = p0;
         assert(p.p() == .125);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/param_ctor.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/param_ctor.pass.cpp
index 75a9b436d5488eeb804facd188d059c1cf4dc968..71710228597d7985f25c076945afc33b165e1742 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/param_ctor.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/param_ctor.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::geometric_distribution<> D;
@@ -31,4 +31,6 @@ int main()
         param_type p(0.25);
         assert(p.p() == 0.25);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/param_eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/param_eq.pass.cpp
index 973491fd8ec068867acda362a999adb808e151ba..a741f06f603b22128d7c9725767b61c74e89b560 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/param_eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/param_eq.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::geometric_distribution<> D;
@@ -33,4 +33,6 @@ int main()
         param_type p2(0.5);
         assert(p1 != p2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/param_types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/param_types.pass.cpp
index bb80250a1b879641fd2233046c02c8f14f12764f..2f9efc268c923935cb553fef4b1d33eea02be96b 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/param_types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/param_types.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::geometric_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         typedef param_type::distribution_type distribution_type;
         static_assert((std::is_same<D, distribution_type>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/set_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/set_param.pass.cpp
index e66f9ace40fa705fc06a3d47ff5cf6d0274cb824..74d49d5d8e2e901f0d52253a238bca3681f70607 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/set_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/set_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::geometric_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         d.param(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/types.pass.cpp
index 528996f50412004bed2016b6e34789f890e92781..a62b66134e7bc9dddc87488e9e0bb58e6c5d76e2 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.geo/types.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::geometric_distribution<> D;
@@ -28,4 +28,6 @@ int main()
         typedef D::result_type result_type;
         static_assert((std::is_same<result_type, long>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/assign.pass.cpp
index 8b6d1e5a55f65cfee11e028c0de70e6f22dc9dea..20f7f9ffd10c8c74b2488dd5a50188d6bf0f3ce0 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/assign.pass.cpp
@@ -27,7 +27,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/copy.pass.cpp
index 68c7703b27085ea136a7759d05cce173c9d75835..73ee12e430ba85f45be511cd956273a814ee68b6 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/copy.pass.cpp
@@ -25,7 +25,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/ctor_int_double.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/ctor_int_double.pass.cpp
index 3b18e806890acd16d18aaf885a480acf0b3b7638..0b9418b7c26a36264f1076b7c5124fe4d0c50bbd 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/ctor_int_double.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/ctor_int_double.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::negative_binomial_distribution<> D;
@@ -36,4 +36,6 @@ int main()
         assert(d.k() == 3);
         assert(d.p() == 0.75);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/ctor_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/ctor_param.pass.cpp
index 51b875da9688be9ef579c15fb67e87ebcb4abdbb..485a3ae98f9c614743dd91c1e9537647d6adf196 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/ctor_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/ctor_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::negative_binomial_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         assert(d.k() == 5);
         assert(d.p() == 0.25);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/eq.pass.cpp
index 7fa43ae9ad7bb7afa6bff9baed9cd55fd9d0db0a..b93084e479f4373fb72f7722de2f6e7b540114e5 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/eq.pass.cpp
@@ -19,7 +19,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::negative_binomial_distribution<> D;
@@ -39,4 +39,6 @@ int main()
         D d2(4, .25);
         assert(d1 != d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/eval.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/eval.pass.cpp
index 039403eea2f6e85513d1aca7de2d2eb290e37f4e..4a8f78842466fb2bedd4f432e86c2638c8738941 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/eval.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/eval.pass.cpp
@@ -284,7 +284,7 @@ test6()
     assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.03);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
@@ -292,4 +292,6 @@ int main()
     test4();
     test5();
     test6();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/eval_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/eval_param.pass.cpp
index d1f6b62581a39d2ca6e308c8d424cabb62346934..b99f6fb07e5f1f3adb1f5b238f708cbf68c2dc76 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/eval_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/eval_param.pass.cpp
@@ -28,7 +28,7 @@ sqr(T x)
     return x * x;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::negative_binomial_distribution<> D;
@@ -156,4 +156,6 @@ int main()
         assert(std::abs((skew - x_skew) / x_skew) < 0.01);
         assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.03);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/get_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/get_param.pass.cpp
index 0cfe69f0ee4c52eaff7df75bd82254c149d929e9..63fe3804315c52173855071a94ed1aadc24bc37e 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/get_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/get_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::negative_binomial_distribution<> D;
@@ -25,4 +25,6 @@ int main()
         D d(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/io.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/io.pass.cpp
index cb5ca473f54930c4020021012e32f071ac18b2c8..a26f1990617487ff565d7abb5b941ad6c3f683a5 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/io.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/io.pass.cpp
@@ -25,7 +25,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::negative_binomial_distribution<> D;
@@ -37,4 +37,6 @@ int main()
         is >> d2;
         assert(d1 == d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/max.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/max.pass.cpp
index c5c1cc10676b4434a49625f4d9b7280494d84ccb..3bc54a4be4d592af3d6cf479f3c586a607ce742d 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/max.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/max.pass.cpp
@@ -16,11 +16,13 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::negative_binomial_distribution<> D;
         D d(4, .25);
         assert(d.max() == std::numeric_limits<int>::max());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/min.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/min.pass.cpp
index 2dfa797ccc86a0aa66821a2b4b20a6147fb2b27d..b2354d77c0e3573f1e24d7231a8655c779b9813c 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/min.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/min.pass.cpp
@@ -16,11 +16,13 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::negative_binomial_distribution<> D;
         D d(4, .5);
         assert(d.min() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/param_assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/param_assign.pass.cpp
index d2e948771615a383cec61eefd912c066edae0329..7968b01e8436013f0e70f231e28ffbbdfb0d5771 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/param_assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/param_assign.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::negative_binomial_distribution<> D;
@@ -28,4 +28,6 @@ int main()
         assert(p.k() == 6);
         assert(p.p() == .7);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/param_copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/param_copy.pass.cpp
index ded91956961b4f679839ce06649cb10d1b454fe9..b16818b26a4835e51ea40bf027290685eabb4de3 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/param_copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/param_copy.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::negative_binomial_distribution<> D;
@@ -27,4 +27,6 @@ int main()
         assert(p.k() == 10);
         assert(p.p() == .125);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/param_ctor.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/param_ctor.pass.cpp
index 0fc228a32d159029ee94dcfd12dcab63517707dd..ad7908d314c1c162fae11cb8c487a3155ebdd3f8 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/param_ctor.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/param_ctor.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::negative_binomial_distribution<> D;
@@ -40,4 +40,6 @@ int main()
         assert(p.k() == 10);
         assert(p.p() == 0.25);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/param_eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/param_eq.pass.cpp
index d65fa544f7a8a57499f6979e5825b2cb064705c6..793b4361cd9447c87053e6636ac4db43074cc8e8 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/param_eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/param_eq.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::negative_binomial_distribution<> D;
@@ -33,4 +33,6 @@ int main()
         param_type p2(3, 0.5);
         assert(p1 != p2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/param_types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/param_types.pass.cpp
index 0ac9230ce02c17d255f583bbb61dfa899b5e51d6..c0164edc8faadc9a4e644703bb61017a81dbfd38 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/param_types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/param_types.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::negative_binomial_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         typedef param_type::distribution_type distribution_type;
         static_assert((std::is_same<D, distribution_type>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/set_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/set_param.pass.cpp
index d785330a4e3831f02e3285c678eb97dfa41f23e6..8971be5ee48b6a693eeff5acc7458e6f78622324 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/set_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/set_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::negative_binomial_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         d.param(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/types.pass.cpp
index 6d2b75585b9cc0a625090c307eb506dbe961724f..ea177377a88159134b8c51a49af54c40b86e7528 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.bern/rand.dist.bern.negbin/types.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::negative_binomial_distribution<> D;
@@ -28,4 +28,6 @@ int main()
         typedef D::result_type result_type;
         static_assert((std::is_same<result_type, long>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/nothing_to_do.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/assign.pass.cpp
index 66d5a7adeaa10d8a138d4fcee8d6bf933230f49e..dfe8785ff9fb0a9102554ecbe0191605e85db0c7 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/assign.pass.cpp
@@ -27,7 +27,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/copy.pass.cpp
index 3d7db5423b4d55d37382f5d359d628050e1ea5b3..85511d161077b9de6db4e5695ace8e325cb2514f 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/copy.pass.cpp
@@ -25,7 +25,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/ctor_double_double.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/ctor_double_double.pass.cpp
index eb4068c4b2e5a824477ba929f983191099d9e0d6..f452b6e0bf377706100bbd71edd3d4f4084557b6 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/ctor_double_double.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/ctor_double_double.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::cauchy_distribution<> D;
@@ -36,4 +36,6 @@ int main()
         assert(d.a() == 14.5);
         assert(d.b() == 5.25);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/ctor_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/ctor_param.pass.cpp
index aedfbb5d3b62bd2befe158b0a22ebe57647e2042..3a8ed3cc959fcbd97c38cb712f2a88c6f61c4d33 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/ctor_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/ctor_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::cauchy_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         assert(d.a() == 0.25);
         assert(d.b() == 10);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/eq.pass.cpp
index e4e29635697a0e633abf2862180f51df9b89689f..bc42b94f9ec569066c59f5bc4908a2880e3a7d5e 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/eq.pass.cpp
@@ -19,7 +19,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::cauchy_distribution<> D;
@@ -33,4 +33,6 @@ int main()
         D d2(2.5, 4.5);
         assert(d1 != d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/eval.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/eval.pass.cpp
index f578164bdef1554ff5c7e03b7ed7f22c703ea711..2b63645ae7d92e3e31fd9c50cd7279b3025677db 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/eval.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/eval.pass.cpp
@@ -26,7 +26,7 @@ f(double x, double a, double b)
     return 1/3.1415926535897932 * std::atan((x - a)/b) + .5;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::cauchy_distribution<> D;
@@ -73,4 +73,6 @@ int main()
         for (int i = 0; i < N; ++i)
             assert(std::abs(f(u[i], a, b) - double(i)/N) < .001);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/eval_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/eval_param.pass.cpp
index 450e19225632ee000e0e1e51b27f7ab24bb29ac4..56921fe0fa729fff719b850299073cdac360afed 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/eval_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/eval_param.pass.cpp
@@ -26,7 +26,7 @@ f(double x, double a, double b)
     return 1/3.1415926535897932 * std::atan((x - a)/b) + .5;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::cauchy_distribution<> D;
@@ -79,4 +79,6 @@ int main()
         for (int i = 0; i < N; ++i)
             assert(std::abs(f(u[i], a, b) - double(i)/N) < .001);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/get_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/get_param.pass.cpp
index 635d116eb0e04530ba0b88ccd27bc9cdb79020b0..c3c88b8d7e0ab0a0f22cc7f383dd18d94ce448ca 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/get_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/get_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::cauchy_distribution<> D;
@@ -25,4 +25,6 @@ int main()
         D d(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/io.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/io.pass.cpp
index 73a7e11aeb85b33d1f31976df2ec9031e907b494..db50cfd5c938359be0ba8b4cb2a766c3b9be0495 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/io.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/io.pass.cpp
@@ -25,7 +25,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::cauchy_distribution<> D;
@@ -37,4 +37,6 @@ int main()
         is >> d2;
         assert(d1 == d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/max.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/max.pass.cpp
index bfde51747e8fe7fbf0c8f095764ba94d7417bc66..963e8ed379b864d94d6bdb6969ff353c8296b876 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/max.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/max.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::cauchy_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         D::result_type m = d.max();
         assert(m == INFINITY);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/min.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/min.pass.cpp
index 2e2ba7db803022eae57bfeea59dbafd53e762f26..59044b8e2726812f4fd482e780d4a5a209c90101 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/min.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/min.pass.cpp
@@ -16,11 +16,13 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::cauchy_distribution<> D;
         D d(.5, .5);
         assert(d.min() == -INFINITY);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/param_assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/param_assign.pass.cpp
index c2a7a04dcdb325b51b414dc5c9819ed1a26295db..04d94e74db5fcb01abb96552df188d646da7a74c 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/param_assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/param_assign.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::cauchy_distribution<> D;
@@ -28,4 +28,6 @@ int main()
         assert(p.a() == .75);
         assert(p.b() == 6);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/param_copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/param_copy.pass.cpp
index 0ee42ef64180a13e063e0b83a3f93266694b33c5..88739df6827cd0e071367e6044bd5c0c87b54b11 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/param_copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/param_copy.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::cauchy_distribution<> D;
@@ -27,4 +27,6 @@ int main()
         assert(p.a() == 10);
         assert(p.b() == .125);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/param_ctor.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/param_ctor.pass.cpp
index 3c44670683da4cc0849611469548f630c5d9740f..8563bafbb8c20114d299cbb3fb13578ad9f995cd 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/param_ctor.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/param_ctor.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::cauchy_distribution<> D;
@@ -40,4 +40,6 @@ int main()
         assert(p.a() == 10);
         assert(p.b() == 5);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/param_eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/param_eq.pass.cpp
index 12ce7de78a01a6c469d6cfe25a73b60a32169a75..97553701ecf00221dcb0d0963ecb06cc08a39746 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/param_eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/param_eq.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::cauchy_distribution<> D;
@@ -33,4 +33,6 @@ int main()
         param_type p2(0.5, .5);
         assert(p1 != p2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/param_types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/param_types.pass.cpp
index 327d1e7d63be6f58993cec6f1ded2e9b9c46ec2e..ca0539c4140590919826f44e26277557ca7793c3 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/param_types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/param_types.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::cauchy_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         typedef param_type::distribution_type distribution_type;
         static_assert((std::is_same<D, distribution_type>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/set_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/set_param.pass.cpp
index 9b5b4af160bde725e7977447e32f2dc5afcae17a..ba66ec16ab653d751461a1823ccbc3c06369653f 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/set_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/set_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::cauchy_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         d.param(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/types.pass.cpp
index b88e6328ab2267022712cf509b6b029363649902..09f79da51260eb886f2a8c51f6f4891ce2bb5c95 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.cauchy/types.pass.cpp
@@ -18,7 +18,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::cauchy_distribution<> D;
@@ -30,4 +30,6 @@ int main()
         typedef D::result_type result_type;
         static_assert((std::is_same<result_type, float>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/assign.pass.cpp
index cd25b1929b04e20c7d76bfda99eb3522b4a19722..75242c2b9438d1813389c2c218bd317127688762 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/assign.pass.cpp
@@ -27,7 +27,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/copy.pass.cpp
index c7881c686032f126a007749f8daf46a95ab97003..3eeba40d01e509c5cf5154eb6ccc7940326ec874 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/copy.pass.cpp
@@ -25,7 +25,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/ctor_double.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/ctor_double.pass.cpp
index 77279803e9fd4eadd23853d8402e0731f981b5d4..a778b2face4884efbd79c5af69e7d71de5444566 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/ctor_double.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/ctor_double.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::chi_squared_distribution<> D;
@@ -28,4 +28,6 @@ int main()
         D d(14.5);
         assert(d.n() == 14.5);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/ctor_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/ctor_param.pass.cpp
index 7cf8c7dfb5ad47f48fa830df8bcc68bace3113ec..922e44f6116f99e505a848dd5b42958067f5043a 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/ctor_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/ctor_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::chi_squared_distribution<> D;
@@ -25,4 +25,6 @@ int main()
         D d(p);
         assert(d.n() == 0.25);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/eq.pass.cpp
index f26b78a79969aeac86fd4632b36ae2c8bbdddbc7..8b9ad4574286c3b140428097a12cf501f9a9dbd2 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/eq.pass.cpp
@@ -19,7 +19,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::chi_squared_distribution<> D;
@@ -33,4 +33,6 @@ int main()
         D d2(4.5);
         assert(d1 != d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/eval.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/eval.pass.cpp
index 81f3359ebc5c4cdd4b6a4d2c71d81158ddc7c8a5..b080886a8d16c26a2d27d44e3a5510054751beb0 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/eval.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/eval.pass.cpp
@@ -29,7 +29,7 @@ sqr(T x)
     return x * x;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::chi_squared_distribution<> D;
@@ -148,4 +148,6 @@ int main()
         assert(std::abs((skew - x_skew) / x_skew) < 0.01);
         assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.01);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/eval_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/eval_param.pass.cpp
index 09a33327f4dc2231e60e4d05d26b41d2c428f06b..86ac86ed350848722969fd8bb1f3cc00cf33fae3 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/eval_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/eval_param.pass.cpp
@@ -29,7 +29,7 @@ sqr(T x)
     return x * x;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::chi_squared_distribution<> D;
@@ -154,4 +154,6 @@ int main()
         assert(std::abs((skew - x_skew) / x_skew) < 0.01);
         assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.01);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/get_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/get_param.pass.cpp
index 0173fb3f41e5aa67ce7a773bb99ff2e0ad2dc63a..55fda0872c65b5a448f87f94b769c80bd14beaec 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/get_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/get_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::chi_squared_distribution<> D;
@@ -25,4 +25,6 @@ int main()
         D d(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/io.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/io.pass.cpp
index fde2fecf009f48671a309cbf40247ffd7f63c468..1017861318f2a7d2a2e968ea168efb9512863b84 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/io.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/io.pass.cpp
@@ -25,7 +25,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::chi_squared_distribution<> D;
@@ -37,4 +37,6 @@ int main()
         is >> d2;
         assert(d1 == d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/max.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/max.pass.cpp
index d5b337f2c56aa5a14eaec05f15d40219b6a60533..19ab87ca9e3b91ce9ea015d90e4f54a41c46dba1 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/max.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/max.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::chi_squared_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         D::result_type m = d.max();
         assert(m == INFINITY);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/min.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/min.pass.cpp
index 54d800559c6a0b40fe2942850d5e27afd64506e9..af5b4561728ba560f05abdc8247308a7e3d45558 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/min.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/min.pass.cpp
@@ -16,11 +16,13 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::chi_squared_distribution<> D;
         D d(.5);
         assert(d.min() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/param_assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/param_assign.pass.cpp
index fa243f22c34edaa586a5d5c8e506f1049d492bdf..0b13690f2b0f3e99d5195367d25b096416d29bef 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/param_assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/param_assign.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::chi_squared_distribution<> D;
@@ -27,4 +27,6 @@ int main()
         p = p0;
         assert(p.n() == .75);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/param_copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/param_copy.pass.cpp
index c73f93a321f1fbc75a1f9d7748a9c59c8d316d23..22fe4b4ec306a8fd3b6bf6c2819332117d2ab339 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/param_copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/param_copy.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::chi_squared_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         param_type p = p0;
         assert(p.n() == 10);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/param_ctor.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/param_ctor.pass.cpp
index 34476f939f525791245a310d7d5becb5f0a03394..b3bbd8668a0a45fb112eb3e8d976773f3331f962 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/param_ctor.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/param_ctor.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::chi_squared_distribution<> D;
@@ -31,4 +31,6 @@ int main()
         param_type p(10);
         assert(p.n() == 10);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/param_eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/param_eq.pass.cpp
index e40f5d19f8f57d658cb0181005bb942072c5cc46..f615acad8c5e7089a3a08115f6f80aaa76168d37 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/param_eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/param_eq.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::chi_squared_distribution<> D;
@@ -33,4 +33,6 @@ int main()
         param_type p2(0.5);
         assert(p1 != p2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/param_types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/param_types.pass.cpp
index 4ecb983b2424aad86a92a3efaff1dbc6f2e5c70f..a6727c429fa790602633e942d7071a939ef79b94 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/param_types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/param_types.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::chi_squared_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         typedef param_type::distribution_type distribution_type;
         static_assert((std::is_same<D, distribution_type>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/set_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/set_param.pass.cpp
index eecfbf2feee1c10e680cf83442b0d6fc51ae895e..d497407e1e0e74b2198de02dac707be68bfa0994 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/set_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/set_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::chi_squared_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         d.param(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/types.pass.cpp
index d211af8bbc8f9a1f2f6d4f6defe835a95c3f7d4f..e33551debf2ab4911d685031bed34359b05492c4 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.chisq/types.pass.cpp
@@ -18,7 +18,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::chi_squared_distribution<> D;
@@ -30,4 +30,6 @@ int main()
         typedef D::result_type result_type;
         static_assert((std::is_same<result_type, float>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/assign.pass.cpp
index c7eb0f983b10598f3fa9f4c429bd54f272505d68..c73d46ccb0f3a3b68589f63ba9562e045d0d947c 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/assign.pass.cpp
@@ -27,7 +27,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/copy.pass.cpp
index 6ef45d0d55af33503fd19f6cfbeeddc70721e138..9a9670154b43236433ff3036c22b80549d693478 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/copy.pass.cpp
@@ -25,7 +25,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/ctor_double_double.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/ctor_double_double.pass.cpp
index 8b5acf39993c86396eea3f396efafb52af102c54..b29664ee48638966dfc514a8e1b7794613f9dc1a 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/ctor_double_double.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/ctor_double_double.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::fisher_f_distribution<> D;
@@ -36,4 +36,6 @@ int main()
         assert(d.m() == 14.5);
         assert(d.n() == 5.25);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/ctor_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/ctor_param.pass.cpp
index 2762c8dbb0fb390916e6cb6f66d014e8daad81d4..3318d52229fe9adefa61a28f730528e511fca283 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/ctor_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/ctor_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::fisher_f_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         assert(d.m() == 0.25);
         assert(d.n() == 10);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/eq.pass.cpp
index ea040c9c62c2a1668e7bb07215f1de6f1adfe563..b91da051158df3b77a5b0c7e9b7452296b7ed4d9 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/eq.pass.cpp
@@ -19,7 +19,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::fisher_f_distribution<> D;
@@ -33,4 +33,6 @@ int main()
         D d2(2.5, 4.5);
         assert(d1 != d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/eval.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/eval.pass.cpp
index 55c8ccf1b0aba8fd2633a43fda5e19af394307e6..9a4cdf175d222880657f1296a9b4235cca3f05bd 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/eval.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/eval.pass.cpp
@@ -45,7 +45,7 @@ f(double x, double m, double n)
     return I(m * x / (m*x + n), static_cast<unsigned>(m/2), static_cast<unsigned>(n/2));
 }
 
-int main()
+int main(int, char**)
 {
     // Purposefully only testing even integral values of m and n (for now)
     {
@@ -99,4 +99,6 @@ int main()
         for (int i = 0; i < N; ++i)
             assert(std::abs(f(u[i], d.m(), d.n()) - double(i)/N) < .01);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/eval_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/eval_param.pass.cpp
index 13818e02600f211f0c1bccef82acf17b875bf057..59a19d57ed269121d200297b88fa637ded1c5696 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/eval_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/eval_param.pass.cpp
@@ -45,7 +45,7 @@ f(double x, double m, double n)
     return I(m * x / (m*x + n), static_cast<unsigned>(m/2), static_cast<unsigned>(n/2));
 }
 
-int main()
+int main(int, char**)
 {
     // Purposefully only testing even integral values of m and n (for now)
     {
@@ -105,4 +105,6 @@ int main()
         for (int i = 0; i < N; ++i)
             assert(std::abs(f(u[i], p.m(), p.n()) - double(i)/N) < .01);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/get_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/get_param.pass.cpp
index 386696acec5a57678ef93989c7ecbc3781a3759e..716d852dd10e5b5ad45e459b55685ba4c07f9cea 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/get_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/get_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::fisher_f_distribution<> D;
@@ -25,4 +25,6 @@ int main()
         D d(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/io.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/io.pass.cpp
index c08d61e1d24590c7cc09ca7b9929334d807ec993..870d086ccd650d286ab2a7a94791c58eaf7ecad4 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/io.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/io.pass.cpp
@@ -25,7 +25,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::fisher_f_distribution<> D;
@@ -37,4 +37,6 @@ int main()
         is >> d2;
         assert(d1 == d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/max.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/max.pass.cpp
index 27bd09fc142d26170006de9f8ffe3fbb7799a987..5e9c2968bd7c7d7de56cca807ce9d61f9da5e817 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/max.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/max.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::fisher_f_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         D::result_type m = d.max();
         assert(m == INFINITY);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/min.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/min.pass.cpp
index a3e382c7f9acec537ce5a6bedf7efec450956b27..8aca42d94e7ac11114e1ab514fc34a07077873de 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/min.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/min.pass.cpp
@@ -16,11 +16,13 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::fisher_f_distribution<> D;
         D d(.5, .5);
         assert(d.min() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/param_assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/param_assign.pass.cpp
index d026525e73258d1ee3a9285c6fd5a2b6b366e788..3622aeb3933c73ad05ac685e31300c4d7421ec37 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/param_assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/param_assign.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::fisher_f_distribution<> D;
@@ -28,4 +28,6 @@ int main()
         assert(p.m() == .75);
         assert(p.n() == 6);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/param_copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/param_copy.pass.cpp
index 21364a393e5254e008ff39022ebd0d464beb33ea..cc936174c3825f5d4e9cd92813808c5f5a0a76bd 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/param_copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/param_copy.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::fisher_f_distribution<> D;
@@ -27,4 +27,6 @@ int main()
         assert(p.m() == 10);
         assert(p.n() == .125);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/param_ctor.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/param_ctor.pass.cpp
index 7adacd37b90614ca0801ea429d5b56d4e1151376..b7bef507d08ea5cb59a6c7ade3dd303ab45f0991 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/param_ctor.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/param_ctor.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::fisher_f_distribution<> D;
@@ -40,4 +40,6 @@ int main()
         assert(p.m() == 10);
         assert(p.n() == 5);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/param_eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/param_eq.pass.cpp
index f4fb9bb9f65ea35f045aa2c48755f8ed56db696d..1345723ec1b2dd4da513cafff61698060d0216b2 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/param_eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/param_eq.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::fisher_f_distribution<> D;
@@ -33,4 +33,6 @@ int main()
         param_type p2(0.5, .5);
         assert(p1 != p2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/param_types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/param_types.pass.cpp
index 3a716bf7c8924ed1a5e74f3e22fb2864b3bfd3eb..8fdb9fccfcc9af04897ffa166a7c206e1952e90e 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/param_types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/param_types.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::fisher_f_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         typedef param_type::distribution_type distribution_type;
         static_assert((std::is_same<D, distribution_type>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/set_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/set_param.pass.cpp
index 9164f750fe04f41ce03706a4863d8dd8e18a6b4f..cad5deda3ca773dbe5911a067f04ecdaa8dd4acf 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/set_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/set_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::fisher_f_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         d.param(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/types.pass.cpp
index ee96f34606673dc7c9826c6919da253a57298988..567ed9f127371f2ee2c21e75a5c557c726537c5b 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.f/types.pass.cpp
@@ -18,7 +18,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::fisher_f_distribution<> D;
@@ -30,4 +30,6 @@ int main()
         typedef D::result_type result_type;
         static_assert((std::is_same<result_type, float>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/assign.pass.cpp
index 20157a2eda04cf0858fd9d1489c1f0d1bfdc8844..567ae63b8a545108f884f5ea8c7929c3d7d481dd 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/assign.pass.cpp
@@ -27,7 +27,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/copy.pass.cpp
index 4e73c9d22098223f70ae02264cb0dbb976e3d5de..f27ea836a9912e14f44eb89f8bd2f995e7b5eaea 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/copy.pass.cpp
@@ -25,7 +25,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/ctor_double_double.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/ctor_double_double.pass.cpp
index d1116cca6e158449d8bad23d919b2a677fc47771..e19839f2a483a2ff85cf6fffe21acd5421ad90df 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/ctor_double_double.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/ctor_double_double.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::lognormal_distribution<> D;
@@ -36,4 +36,6 @@ int main()
         assert(d.m() == 14.5);
         assert(d.s() == 5.25);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/ctor_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/ctor_param.pass.cpp
index f88d433059bf35190800b57391caa371d186f40b..09ee798b8fd82e91ba44f337f7d741c71bf20120 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/ctor_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/ctor_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::lognormal_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         assert(d.m() == 0.25);
         assert(d.s() == 10);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/eq.pass.cpp
index 627f57961207cae405ec297aa37231b3757b01d0..7257f57b1dcc90fc4870f954b5718c9eefedc0b9 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/eq.pass.cpp
@@ -19,7 +19,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::lognormal_distribution<> D;
@@ -33,4 +33,6 @@ int main()
         D d2(2.5, 4.5);
         assert(d1 != d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/eval.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/eval.pass.cpp
index bcbc04c32fbb6f5a661ac783d22982db78298983..90841754881c7520b06a1ae89a151e2a11374ada 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/eval.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/eval.pass.cpp
@@ -248,11 +248,13 @@ test5()
     assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.7);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
     test3();
     test4();
     test5();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/eval_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/eval_param.pass.cpp
index 350a32587635eebb7095b17b7a454ad5d01687f1..1c40e66b224f5115d99de2781be215050563ea25 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/eval_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/eval_param.pass.cpp
@@ -258,11 +258,13 @@ test5()
     assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.7);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
     test3();
     test4();
     test5();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/get_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/get_param.pass.cpp
index a553901fe2f1372cf656c9f694ccbc1f986a278b..e56cae65b364ac19606b92c910cd241afaef45f6 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/get_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/get_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::lognormal_distribution<> D;
@@ -25,4 +25,6 @@ int main()
         D d(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/io.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/io.pass.cpp
index 10ee0e820037696258ed3b9bffb6a38ec56838eb..204a8f5f3b2d8dc8ff8000b5e908f6b4a4795f5e 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/io.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/io.pass.cpp
@@ -25,7 +25,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::lognormal_distribution<> D;
@@ -37,4 +37,6 @@ int main()
         is >> d2;
         assert(d1 == d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/max.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/max.pass.cpp
index 815db8a8935fca9a40cabdc316a03d4c6b7690cb..2297a4160d340eb48bfa385f37f38298a2753b3c 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/max.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/max.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::lognormal_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         D::result_type m = d.max();
         assert(m == INFINITY);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/min.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/min.pass.cpp
index d199cc0b999023ee5d707c909d4cd090a6a55399..84154865b93ceef1075a879f700700f85f8a05b0 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/min.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/min.pass.cpp
@@ -16,11 +16,13 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::lognormal_distribution<> D;
         D d(.5, .5);
         assert(d.min() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/param_assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/param_assign.pass.cpp
index 3597e6d470fcffb37aad88422fec1b98c1f6c291..9999b8499f04aefc27e563f6744a399055bfa5ed 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/param_assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/param_assign.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::lognormal_distribution<> D;
@@ -28,4 +28,6 @@ int main()
         assert(p.m() == .75);
         assert(p.s() == 6);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/param_copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/param_copy.pass.cpp
index a0657ce5cca2c5377f1c91b06c9eba8704bbed1d..6ad49592fb191f6d57aad90d67a1b5084006d530 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/param_copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/param_copy.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::lognormal_distribution<> D;
@@ -27,4 +27,6 @@ int main()
         assert(p.m() == 10);
         assert(p.s() == .125);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/param_ctor.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/param_ctor.pass.cpp
index cd533afd87785e4268e0f8e83cf64c5a9795c70e..cb1735b790f6928e7df5af70cb3febb750d5f291 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/param_ctor.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/param_ctor.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::lognormal_distribution<> D;
@@ -40,4 +40,6 @@ int main()
         assert(p.m() == 10);
         assert(p.s() == 5);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/param_eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/param_eq.pass.cpp
index 8e4cd9a6ffa52406b4a381e67e5904592272242b..a6be4db10ad2e440ed11cc3abf25a1730c6d8068 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/param_eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/param_eq.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::lognormal_distribution<> D;
@@ -33,4 +33,6 @@ int main()
         param_type p2(0.5, .5);
         assert(p1 != p2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/param_types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/param_types.pass.cpp
index 7f2b726b14767a991f2cb8e8568fb607f710332b..99f13be070ca4b226e2d87dc8e3ba5825a2dc8ea 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/param_types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/param_types.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::lognormal_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         typedef param_type::distribution_type distribution_type;
         static_assert((std::is_same<D, distribution_type>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/set_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/set_param.pass.cpp
index bc67664b0e5c3cb7636159bca3ee77fa1f772113..9924757177d66460f7eedf781544e6c38c3f585a 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/set_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/set_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::lognormal_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         d.param(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/types.pass.cpp
index ae8b59b661517b49bf1b579b7ae26a143c70e9a2..6bff26088a05a301287efe2873d5bdbdf1a30363 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.lognormal/types.pass.cpp
@@ -18,7 +18,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::lognormal_distribution<> D;
@@ -30,4 +30,6 @@ int main()
         typedef D::result_type result_type;
         static_assert((std::is_same<result_type, float>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/assign.pass.cpp
index 77c3cfbe2dae21a1bc74ca74dd4431636030c838..492a0ea6aefd8e79a5b6cb86de040405d689dd67 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/assign.pass.cpp
@@ -27,7 +27,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/copy.pass.cpp
index fa130e4c9a86dc4b5573659aa779da1735ccb09b..f2326bbc3433238d91e131001717d79fd838c52f 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/copy.pass.cpp
@@ -25,7 +25,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/ctor_double_double.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/ctor_double_double.pass.cpp
index 5081372829bd108dd6b6025acffdc8b28b9ee08b..2c4462f252a1ddf6e510984873230e777e7b00dd 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/ctor_double_double.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/ctor_double_double.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::normal_distribution<> D;
@@ -36,4 +36,6 @@ int main()
         assert(d.mean() == 14.5);
         assert(d.stddev() == 5.25);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/ctor_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/ctor_param.pass.cpp
index bdb5c69f658950b00bd73e55b0e697e43fb23cc0..66331187c52fc5cd0d0add7e5a547d556e604a16 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/ctor_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/ctor_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::normal_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         assert(d.mean() == 0.25);
         assert(d.stddev() == 10);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/eq.pass.cpp
index ff62af28048601bc398263f0257e8de4528d4823..87b7c4d7d0d58cb7f2df8fe1703d8189c6312261 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/eq.pass.cpp
@@ -19,7 +19,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::normal_distribution<> D;
@@ -33,4 +33,6 @@ int main()
         D d2(2.5, 4.5);
         assert(d1 != d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/eval.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/eval.pass.cpp
index b2cf8534d921ccb574a50050565611ba2e112dd5..5362aef09f80e6749fbba000d5be5a0cb231e584 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/eval.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/eval.pass.cpp
@@ -29,7 +29,7 @@ sqr(T x)
     return x * x;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::normal_distribution<> D;
@@ -66,4 +66,6 @@ int main()
         assert(std::abs(skew - x_skew) < 0.01);
         assert(std::abs(kurtosis - x_kurtosis) < 0.01);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/eval_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/eval_param.pass.cpp
index 55f0c8180e6cd8f3819bfe698114ef0a13a80821..343bdd7dc6f7c2770f4e9d53640c282b837c94fe 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/eval_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/eval_param.pass.cpp
@@ -29,7 +29,7 @@ sqr(T x)
     return x * x;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::normal_distribution<> D;
@@ -68,4 +68,6 @@ int main()
         assert(std::abs(skew - x_skew) < 0.01);
         assert(std::abs(kurtosis - x_kurtosis) < 0.01);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/get_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/get_param.pass.cpp
index f173955013f5ae2aabb2bee4dbc3697b226c3c5a..a293371069b4abc392b12d735b5eead70dc17679 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/get_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/get_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::normal_distribution<> D;
@@ -25,4 +25,6 @@ int main()
         D d(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/io.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/io.pass.cpp
index 765c4518789747792cc926bc118f8d3fa3d02afb..601f8d58014b9e322346cdc02341e4737365d5e3 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/io.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/io.pass.cpp
@@ -25,7 +25,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::normal_distribution<> D;
@@ -37,4 +37,6 @@ int main()
         is >> d2;
         assert(d1 == d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/max.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/max.pass.cpp
index 9218cfa8359b49fbae680829ab987d242231a395..24adfc05c7ca150fa91ba1dc5ce1e84e39e350dd 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/max.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/max.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::normal_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         D::result_type m = d.max();
         assert(m == INFINITY);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/min.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/min.pass.cpp
index 1ec4564252772900afca1285dfdaf26086f579e6..0e2c27a183e3f60b5e4b33ef6520d2449d627d18 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/min.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/min.pass.cpp
@@ -16,11 +16,13 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::normal_distribution<> D;
         D d(.5, .5);
         assert(d.min() == -INFINITY);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/param_assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/param_assign.pass.cpp
index 08195232ebaeeb648e00e20e67276f1d61b7bd36..4a37869230bd695fa97abaf1ebd6b6dd00e739ab 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/param_assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/param_assign.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::normal_distribution<> D;
@@ -28,4 +28,6 @@ int main()
         assert(p.mean() == .75);
         assert(p.stddev() == 6);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/param_copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/param_copy.pass.cpp
index cc16ec7e3c1dd676216dec64681f6c34271737ca..7ae72e6dfd229296dd09b68cd161405c7755899e 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/param_copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/param_copy.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::normal_distribution<> D;
@@ -27,4 +27,6 @@ int main()
         assert(p.mean() == 10);
         assert(p.stddev() == .125);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/param_ctor.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/param_ctor.pass.cpp
index f58fd3b5aea5a06b72b5d0ee8e86c1a5592935ac..e947060e5209842165230b1d0cda1b12f45937f5 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/param_ctor.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/param_ctor.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::normal_distribution<> D;
@@ -40,4 +40,6 @@ int main()
         assert(p.mean() == 10);
         assert(p.stddev() == 5);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/param_eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/param_eq.pass.cpp
index 859dba8a4a612acdcf2d5c6955449e401722b96a..cf7fa39cf31bdc57dea76eb5e2e3a23995f42569 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/param_eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/param_eq.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::normal_distribution<> D;
@@ -33,4 +33,6 @@ int main()
         param_type p2(0.5, .5);
         assert(p1 != p2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/param_types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/param_types.pass.cpp
index ef88be7996ed3c2c75db53250f25c3d9033fc318..2fef65e8c294638e08a7065e9acccea77101b1cd 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/param_types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/param_types.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::normal_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         typedef param_type::distribution_type distribution_type;
         static_assert((std::is_same<D, distribution_type>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/set_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/set_param.pass.cpp
index 7b4e9ca4b1c0142c0ce88e01961e023ebb23eebf..46f1cb2ee0596154c5b2ef1d7968c64bac570ce1 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/set_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/set_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::normal_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         d.param(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/types.pass.cpp
index 754e2c28dd291265f3995d68a36708e7010b1e37..f532786c9d8d0e05e40549a73b62d55c309705b3 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.normal/types.pass.cpp
@@ -18,7 +18,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::normal_distribution<> D;
@@ -30,4 +30,6 @@ int main()
         typedef D::result_type result_type;
         static_assert((std::is_same<result_type, float>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/assign.pass.cpp
index e2566347ea3761a9b76f3c2318ec85dc19038a61..bb6ced5e8875d46b2b1165efee2e57e5b1e3e0c7 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/assign.pass.cpp
@@ -27,7 +27,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/copy.pass.cpp
index 0f64eb7cc62eab3d85402e494d5bf36b6adda096..a6aa61180fa965987d0f0fd91de117b0f6a80cac 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/copy.pass.cpp
@@ -25,7 +25,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/ctor_double.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/ctor_double.pass.cpp
index 88827fee4d3f2821631f63d82fd60ca0b5ae671f..a133ff30c622b81da0172fec8bc337f3b7fa9efb 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/ctor_double.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/ctor_double.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::student_t_distribution<> D;
@@ -28,4 +28,6 @@ int main()
         D d(14.5);
         assert(d.n() == 14.5);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/ctor_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/ctor_param.pass.cpp
index ba286242ce3177e41684bed71f9e682e6af17de3..be11e9224c16c9718c47757ffc14b823489ff5da 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/ctor_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/ctor_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::student_t_distribution<> D;
@@ -25,4 +25,6 @@ int main()
         D d(p);
         assert(d.n() == 0.25);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/eq.pass.cpp
index e513658138ab6eb5d28e3606256462b69e2ef366..2de6ca5513bd813d54770063afff03a1478e8f49 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/eq.pass.cpp
@@ -19,7 +19,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::student_t_distribution<> D;
@@ -33,4 +33,6 @@ int main()
         D d2(4.5);
         assert(d1 != d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/eval.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/eval.pass.cpp
index d8b3783e9e3adacfd1e01cdbf23b553f5aa43a19..bb1630ea44df101d9d3601dd814002fe7258eb82 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/eval.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/eval.pass.cpp
@@ -28,7 +28,7 @@ sqr(T x)
     return x * x;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::student_t_distribution<> D;
@@ -135,4 +135,6 @@ int main()
         assert(std::abs(skew - x_skew) < 0.01);
         assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.02);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/eval_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/eval_param.pass.cpp
index cb47b07a6d0f6d8a83f2aa59e0fd09d10c74b8f7..3b939010a99abcee52e1b5536197a4174ff139a4 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/eval_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/eval_param.pass.cpp
@@ -28,7 +28,7 @@ sqr(T x)
     return x * x;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::student_t_distribution<> D;
@@ -141,4 +141,6 @@ int main()
         assert(std::abs(skew - x_skew) < 0.01);
         assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.02);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/get_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/get_param.pass.cpp
index f1cd34de749fd60eae31c1b0d7c9562fd7ae02a6..170aed3dbec4a58c59485cb3bd7b627dcb40b85f 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/get_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/get_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::student_t_distribution<> D;
@@ -25,4 +25,6 @@ int main()
         D d(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/io.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/io.pass.cpp
index 8fb8381daf97ba3c482fcdb7ca7757a1506aee12..60f9a6fb3ffc9cc2db3eb48bb2c9be98a7876bd9 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/io.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/io.pass.cpp
@@ -25,7 +25,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::student_t_distribution<> D;
@@ -37,4 +37,6 @@ int main()
         is >> d2;
         assert(d1 == d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/max.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/max.pass.cpp
index f64207c4063abff143ee82d1151a5056a367cdd6..f2fe365443b73bfb70096992441ad68bf092e92c 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/max.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/max.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::student_t_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         D::result_type m = d.max();
         assert(m == INFINITY);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/min.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/min.pass.cpp
index 8f6d4f65b0c1f811d00363a09dd646b256bcc57a..ab98be4504f642e1e98e2eb60d89459b7d99996e 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/min.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/min.pass.cpp
@@ -16,11 +16,13 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::student_t_distribution<> D;
         D d(.5);
         assert(d.min() == -INFINITY);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/param_assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/param_assign.pass.cpp
index 25137f9c136b2ff561f0c64777fb0b2222d102c6..54e9313ae677d37a9c1a1777bdbd42b2d29fca96 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/param_assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/param_assign.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::student_t_distribution<> D;
@@ -27,4 +27,6 @@ int main()
         p = p0;
         assert(p.n() == .75);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/param_copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/param_copy.pass.cpp
index b207d7dec3b04a94c7697e4248d12d92629751a5..a27a735ca41a88ca3fbcba7f81ced77fc4af2beb 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/param_copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/param_copy.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::student_t_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         param_type p = p0;
         assert(p.n() == 10);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/param_ctor.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/param_ctor.pass.cpp
index bcaac8774e2c261ecf455b65cd226f87ddaaae21..897a3e3cff482e913c6ea6c875235f71009a8a17 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/param_ctor.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/param_ctor.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::student_t_distribution<> D;
@@ -31,4 +31,6 @@ int main()
         param_type p(10);
         assert(p.n() == 10);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/param_eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/param_eq.pass.cpp
index eea4cc99bd8dbbaaa9995e6d0a40ea6728470a36..cd3a04a341e157afeb7945499ff1456d5979cf84 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/param_eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/param_eq.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::student_t_distribution<> D;
@@ -33,4 +33,6 @@ int main()
         param_type p2(0.5);
         assert(p1 != p2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/param_types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/param_types.pass.cpp
index b064d111ce333a13da78769ef91297736be1fcfe..1acecc1d11032a7463c3e4f4f1c31521a1d5b55c 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/param_types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/param_types.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::student_t_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         typedef param_type::distribution_type distribution_type;
         static_assert((std::is_same<D, distribution_type>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/set_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/set_param.pass.cpp
index 2b451681114d60310c5c947a4b16984dd2ef7603..85c6a3cb1cda3cc8d03d24e59e72af3fcdd2372c 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/set_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/set_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::student_t_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         d.param(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/types.pass.cpp
index c9fc1aaccdaa583b2d3cc2ed7b9c2f98954c22ed..f89da9f9ede58c8884062cabf692d5ab70a85554 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.norm/rand.dist.norm.t/types.pass.cpp
@@ -18,7 +18,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::student_t_distribution<> D;
@@ -30,4 +30,6 @@ int main()
         typedef D::result_type result_type;
         static_assert((std::is_same<result_type, float>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/nothing_to_do.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/assign.pass.cpp
index 8ce712a54694fcca4359caaa4a9486e3e1c8a88e..bfee1f279ad8488c5895646e909fdb043152fe31 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/assign.pass.cpp
@@ -27,7 +27,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/copy.pass.cpp
index df5b00fb8bc944782baa8b71b1d11809e02b727f..41119b4fefc3c37e7504b51373988f26e3dfe20a 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/copy.pass.cpp
@@ -25,7 +25,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/ctor_double.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/ctor_double.pass.cpp
index 479f221e0374a77b3438dd2eae05bb12a07325fe..530d7de9a93cf02999a34be906243ce2f6a84660 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/ctor_double.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/ctor_double.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::exponential_distribution<> D;
@@ -28,4 +28,6 @@ int main()
         D d(3.5);
         assert(d.lambda() == 3.5);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/ctor_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/ctor_param.pass.cpp
index 31926e520ed0fbec6b798ca229dd84e209727d50..174e91f8f3112bdb68a39acd65daba2565d06c27 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/ctor_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/ctor_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::exponential_distribution<> D;
@@ -25,4 +25,6 @@ int main()
         D d(p);
         assert(d.lambda() == 0.25);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/eq.pass.cpp
index 27841184cc1dfaa4fa51b5af94765c2941f00232..609f226a54000d5d7ba0ac255285fc9f957a2f83 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/eq.pass.cpp
@@ -19,7 +19,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::exponential_distribution<> D;
@@ -33,4 +33,6 @@ int main()
         D d2(.25);
         assert(d1 != d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/eval.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/eval.pass.cpp
index db71f9c905b01131bece1894fe38ba195e9fa518..bfe7e8da385a5cf129fc3e3cb91c084a11ea0f26 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/eval.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/eval.pass.cpp
@@ -29,7 +29,7 @@ sqr(T x)
     return x * x;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::exponential_distribution<> D;
@@ -148,4 +148,6 @@ int main()
         assert(std::abs((skew - x_skew) / x_skew) < 0.01);
         assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.01);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/eval_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/eval_param.pass.cpp
index 28f6e6d78ac122196f195983e07a608356c1a9bc..00054a76e68f31c053a3bae07320f6b0a8a49fc5 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/eval_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/eval_param.pass.cpp
@@ -29,7 +29,7 @@ sqr(T x)
     return x * x;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::exponential_distribution<> D;
@@ -72,4 +72,6 @@ int main()
         assert(std::abs((skew - x_skew) / x_skew) < 0.01);
         assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.01);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/get_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/get_param.pass.cpp
index c33383261f15081cda7d93cc31ed693a2d82da03..9cb46bf04f69010d1b94cbc051398467ca01ef2b 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/get_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/get_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::exponential_distribution<> D;
@@ -25,4 +25,6 @@ int main()
         D d(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/io.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/io.pass.cpp
index d8b4da1f37b83c2837a828ae2a9117d7ebb315e9..e8613480c6e942955c705d74ada4188d6c838e49 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/io.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/io.pass.cpp
@@ -25,7 +25,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::exponential_distribution<> D;
@@ -37,4 +37,6 @@ int main()
         is >> d2;
         assert(d1 == d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/max.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/max.pass.cpp
index bf02b03bddfa8babf68d08bc734b38622d0daa9a..9859883c1257be8847849fdf7a7f4078c1c20ee1 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/max.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/max.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::exponential_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         D::result_type m = d.max();
         assert(m == std::numeric_limits<D::result_type>::infinity());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/min.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/min.pass.cpp
index abca78185c646b3b18202d1f768f06edc153628a..e1957295213fb7a2df6cb7274169a50d3c1cd842 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/min.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/min.pass.cpp
@@ -16,11 +16,13 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::exponential_distribution<> D;
         D d(.5);
         assert(d.min() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/param_assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/param_assign.pass.cpp
index 47ca9d508a282887e5e8f3748b76a9c3025f7a52..9958d632b2a827703d5b9e68be47fa197240a3f1 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/param_assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/param_assign.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::exponential_distribution<> D;
@@ -27,4 +27,6 @@ int main()
         p = p0;
         assert(p.lambda() == .7);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/param_copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/param_copy.pass.cpp
index df00ddd2286b4bcbbcc2e8bec40bc03f2d16f3d0..676eac6465bd63ba125c466529015c8ead3d9f34 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/param_copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/param_copy.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::exponential_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         param_type p = p0;
         assert(p.lambda() == .125);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/param_ctor.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/param_ctor.pass.cpp
index 9eb9881f5e7d505b151634b01d39d569abac5ec7..8483bf9ff7505ef92e698d26f836ab352170c91b 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/param_ctor.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/param_ctor.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::exponential_distribution<> D;
@@ -31,4 +31,6 @@ int main()
         param_type p(10);
         assert(p.lambda() == 10);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/param_eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/param_eq.pass.cpp
index 085f55639de2eba6daace93c0dbb786b2755edf2..e36ffe029f7ad8f5f2d761c78862167b66a84a30 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/param_eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/param_eq.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::exponential_distribution<> D;
@@ -33,4 +33,6 @@ int main()
         param_type p2(0.5);
         assert(p1 != p2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/param_types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/param_types.pass.cpp
index 9e43dff4a99a71083a12fe0053355224bca1645a..1b137acf9a907bfbc47e40b1ee960fabfd14120a 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/param_types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/param_types.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::exponential_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         typedef param_type::distribution_type distribution_type;
         static_assert((std::is_same<D, distribution_type>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/set_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/set_param.pass.cpp
index bc36185782a129fb3aa9773dbe1f0ea15c2a08f2..7147b313c79fac1faef16f4f4fca210a6857902b 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/set_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/set_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::exponential_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         d.param(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/types.pass.cpp
index fe9f84be0db0d1690915d1b656a40695c7b259a9..289c2f1a4a12681741cbd8f91cb611120ae1b44e 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.exp/types.pass.cpp
@@ -18,7 +18,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::exponential_distribution<> D;
@@ -30,4 +30,6 @@ int main()
         typedef D::result_type result_type;
         static_assert((std::is_same<result_type, float>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/assign.pass.cpp
index 8aab78c0798e5b598404fa49a9e2d6f35412aebe..15333b04804e95c5faf48fb987f19c885748e41d 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/assign.pass.cpp
@@ -27,7 +27,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/copy.pass.cpp
index 48f8b46b792428a2ebded70ef8a1839355eb86ff..a71dd8e31a41c126c5117c1874b9884b4193d4f7 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/copy.pass.cpp
@@ -25,7 +25,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/ctor_double_double.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/ctor_double_double.pass.cpp
index 2b02acf62d9f99cefebf5da72d45f612535d0d62..1123da3f2262d323f65e1c22600a33254e29232c 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/ctor_double_double.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/ctor_double_double.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::extreme_value_distribution<> D;
@@ -36,4 +36,6 @@ int main()
         assert(d.a() == 14.5);
         assert(d.b() == 5.25);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/ctor_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/ctor_param.pass.cpp
index 3e569438a00cc178ddafaa47941ec29277559bc1..4160b0337e3abec1fbe5803c03b539b3ed23bf9f 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/ctor_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/ctor_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::extreme_value_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         assert(d.a() == 0.25);
         assert(d.b() == 10);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/eq.pass.cpp
index 8d5e08f5ce0b102e87530fc59113e6345847d172..ab14c2ac5c4661cc7a1b9b0b8cc1e7d8e08f6568 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/eq.pass.cpp
@@ -19,7 +19,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::extreme_value_distribution<> D;
@@ -33,4 +33,6 @@ int main()
         D d2(2.5, 4.5);
         assert(d1 != d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/eval.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/eval.pass.cpp
index 42ccae9c85eba0fd942a33f55f97e042b7e9c834..c83e78e01f69545ca81a9c7057558285dff8ceab 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/eval.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/eval.pass.cpp
@@ -192,10 +192,12 @@ test4()
     assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.01);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
     test3();
     test4();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/eval_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/eval_param.pass.cpp
index ef1ca6aafe527c551a962fd723fa17db405ce454..bf3df44555986e98994ac7ebf98d93542423d941 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/eval_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/eval_param.pass.cpp
@@ -200,10 +200,12 @@ test4()
     assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.01);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
     test3();
     test4();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/get_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/get_param.pass.cpp
index fe300d6920ca7d45701d4ea4f819bce231c45d25..27499a49a5f86fd20c6b4fc31def58c74a6e849c 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/get_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/get_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::extreme_value_distribution<> D;
@@ -25,4 +25,6 @@ int main()
         D d(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/io.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/io.pass.cpp
index 9fefd6058b4ae1bc9f74988af9be6e64f7d5819d..219d0f1e2da7b89eff352d65c481c38ba2e0a6ce 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/io.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/io.pass.cpp
@@ -25,7 +25,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::extreme_value_distribution<> D;
@@ -37,4 +37,6 @@ int main()
         is >> d2;
         assert(d1 == d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/max.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/max.pass.cpp
index b16f7f2a5c19c60c80e17c6eab8129cc04d30f07..bfa6f24835654d31566a5396a0f1bbcebb5e47ec 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/max.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/max.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::extreme_value_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         D::result_type m = d.max();
         assert(m == INFINITY);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/min.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/min.pass.cpp
index 199c14e5f75930d031f78039e2320ff9cadb3eb1..bd97a0ba3965d0ab4ed45f0b8abea8283fa73126 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/min.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/min.pass.cpp
@@ -16,11 +16,13 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::extreme_value_distribution<> D;
         D d(.5, .5);
         assert(d.min() == -INFINITY);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/param_assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/param_assign.pass.cpp
index cd2aac8cafd66416b551e2dc2d777035fd8d945a..b92b6fbe933960c38bbc746929cd79d1d56edf2b 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/param_assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/param_assign.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::extreme_value_distribution<> D;
@@ -28,4 +28,6 @@ int main()
         assert(p.a() == .75);
         assert(p.b() == 6);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/param_copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/param_copy.pass.cpp
index 58ad1f2c972393e22807d3d25b2f6619ecb0fc66..f64a32030506c532bd740b3801497ba01728f1a0 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/param_copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/param_copy.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::extreme_value_distribution<> D;
@@ -27,4 +27,6 @@ int main()
         assert(p.a() == 10);
         assert(p.b() == .125);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/param_ctor.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/param_ctor.pass.cpp
index 3dd5e788e89f6dc7fcaf9bacf2b588031fa339bd..906f7160afc7ae1d41fb3789a4139a9a8024206a 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/param_ctor.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/param_ctor.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::extreme_value_distribution<> D;
@@ -40,4 +40,6 @@ int main()
         assert(p.a() == 10);
         assert(p.b() == 5);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/param_eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/param_eq.pass.cpp
index 532452c2e77bb87a4b874c88ce899ecb1a1cf44c..c4e4a7060ea9e64287b07e6c40ddfdc2c31d3596 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/param_eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/param_eq.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::extreme_value_distribution<> D;
@@ -33,4 +33,6 @@ int main()
         param_type p2(0.5, .5);
         assert(p1 != p2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/param_types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/param_types.pass.cpp
index af00f4b7ff02cc9f9ce55cd0c90e13e56f8e7716..30c46459bb6a43a0240f8828f83abad686a913d2 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/param_types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/param_types.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::extreme_value_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         typedef param_type::distribution_type distribution_type;
         static_assert((std::is_same<D, distribution_type>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/set_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/set_param.pass.cpp
index f7ff8fdf473a2d1e4f2b97e5588348df1d58947e..88fff04fb102da2b7e3a84f00ccaadf166ffdb6c 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/set_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/set_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::extreme_value_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         d.param(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/types.pass.cpp
index 53ad76218b3ee74d53741b2f79db49e29e1f7f35..e96c0d4ad4555852db0e5f8ff97a4a6c64a4288f 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.extreme/types.pass.cpp
@@ -18,7 +18,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::extreme_value_distribution<> D;
@@ -30,4 +30,6 @@ int main()
         typedef D::result_type result_type;
         static_assert((std::is_same<result_type, float>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/assign.pass.cpp
index 707c5b4b1da87fcd06514fa8a85bfc604d14f9b8..35eb5c277cb2cd80463e52857984131c21cd7d65 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/assign.pass.cpp
@@ -27,7 +27,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/copy.pass.cpp
index b080f76a8a80dec1c4f61ea77664cc84d420d139..962374efe876eacaea3172dacdd334554d5f7ce4 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/copy.pass.cpp
@@ -25,7 +25,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/ctor_double_double.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/ctor_double_double.pass.cpp
index c359c08db1508a9706b35fe1f8d89c881943a73b..31ce06d15aa9d59c3d409709da5308499d4d9c8d 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/ctor_double_double.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/ctor_double_double.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::gamma_distribution<> D;
@@ -36,4 +36,6 @@ int main()
         assert(d.alpha() == 14.5);
         assert(d.beta() == 5.25);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/ctor_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/ctor_param.pass.cpp
index a475a67f5a4806211c0fd0ddca938304f30a6cc5..c78821f871dd0b49b6a75d198547b8d90bda118b 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/ctor_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/ctor_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::gamma_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         assert(d.alpha() == 0.25);
         assert(d.beta() == 10);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/eq.pass.cpp
index 932c57a06f90309f16fe6380e7d6fa82050e05a5..ee365f8e7c27879a2b3d0579da15dbd6360c0061 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/eq.pass.cpp
@@ -19,7 +19,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::gamma_distribution<> D;
@@ -33,4 +33,6 @@ int main()
         D d2(2.5, 4.5);
         assert(d1 != d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/eval.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/eval.pass.cpp
index b972c3f5e8b6efe25a5e436a4c2a6e5167283b11..f9e678d1caab2725be444cc12005676a7f4f1b5d 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/eval.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/eval.pass.cpp
@@ -28,7 +28,7 @@ sqr(T x)
     return x * x;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::gamma_distribution<> D;
@@ -147,4 +147,6 @@ int main()
         assert(std::abs((skew - x_skew) / x_skew) < 0.01);
         assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.01);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/eval_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/eval_param.pass.cpp
index 803daa82e3ef0a33dee196205a5f679d0e4abbc6..aeb0bbf31e0f2e0ceb58ffafdbb6bcad4b941b8e 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/eval_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/eval_param.pass.cpp
@@ -28,7 +28,7 @@ sqr(T x)
     return x * x;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::gamma_distribution<> D;
@@ -153,4 +153,6 @@ int main()
         assert(std::abs((skew - x_skew) / x_skew) < 0.01);
         assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.01);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/get_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/get_param.pass.cpp
index 31bbbfca87abb3379ea36a5d62f8954d23b7446b..82b1c9bfd7823c8e43fe90300d6358356a55c6d7 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/get_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/get_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::gamma_distribution<> D;
@@ -25,4 +25,6 @@ int main()
         D d(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/io.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/io.pass.cpp
index 6824616bdfccf5c5bdec12a44c4596df8eb100b1..6732ca210ffa355d46c8b2c6b3f6cf13f3910a13 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/io.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/io.pass.cpp
@@ -25,7 +25,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::gamma_distribution<> D;
@@ -37,4 +37,6 @@ int main()
         is >> d2;
         assert(d1 == d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/max.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/max.pass.cpp
index 29df499678d9a957be86bd03e1b77993c367083a..eb9e2b4f2e0f016e55e74942b73d7c9c4102275e 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/max.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/max.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::gamma_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         D::result_type m = d.max();
         assert(m == INFINITY);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/min.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/min.pass.cpp
index 37eba2f10cf8ef8d3d5ee05ee2a8cc415ab1b07b..3eda5a65183cc2022f812324a8b55c7c573610d5 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/min.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/min.pass.cpp
@@ -16,11 +16,13 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::gamma_distribution<> D;
         D d(.5, .5);
         assert(d.min() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/param_assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/param_assign.pass.cpp
index 4470505003e1825ef662e47561d2756b928c6da9..28d3997c4d61c425b7ad693691a19ee0a9037c81 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/param_assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/param_assign.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::gamma_distribution<> D;
@@ -28,4 +28,6 @@ int main()
         assert(p.alpha() == .75);
         assert(p.beta() == 6);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/param_copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/param_copy.pass.cpp
index d7eb86d23a4e0ebd16b2599209985df14632ccf5..dc2b32dd7eecf4c20cf20a927794654cf7e39bd6 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/param_copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/param_copy.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::gamma_distribution<> D;
@@ -27,4 +27,6 @@ int main()
         assert(p.alpha() == 10);
         assert(p.beta() == .125);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/param_ctor.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/param_ctor.pass.cpp
index 3c72bee5aaee90b9145a4a0a7e4a83119308ab3b..333b670f1dae3457221ead9baf792d328fb7853c 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/param_ctor.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/param_ctor.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::gamma_distribution<> D;
@@ -40,4 +40,6 @@ int main()
         assert(p.alpha() == 10);
         assert(p.beta() == 5);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/param_eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/param_eq.pass.cpp
index d8cbeb23af191699fe5fee261633aa358fe2fe1d..2ba854163de9c32eb5c7f5586f7092c6ad541192 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/param_eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/param_eq.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::gamma_distribution<> D;
@@ -33,4 +33,6 @@ int main()
         param_type p2(0.5, .5);
         assert(p1 != p2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/param_types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/param_types.pass.cpp
index f9467d6a1a8cc678ce545afe883ab90a824457eb..0fc07ef95843ef8b8e4c443aa981faee94be7ca4 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/param_types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/param_types.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::gamma_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         typedef param_type::distribution_type distribution_type;
         static_assert((std::is_same<D, distribution_type>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/set_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/set_param.pass.cpp
index ca1c4b48d7d752f29d8ffa71eb9e392aaf76b0ef..4af868a270be3f87290cf2808a020031c94ed699 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/set_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/set_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::gamma_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         d.param(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/types.pass.cpp
index 197a9b224d575d8a1fccdbf2523a1d148ed452d5..31a33c0cf8acdabe06a6afde8d48396e30729d23 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.gamma/types.pass.cpp
@@ -18,7 +18,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::gamma_distribution<> D;
@@ -30,4 +30,6 @@ int main()
         typedef D::result_type result_type;
         static_assert((std::is_same<result_type, float>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/assign.pass.cpp
index ee487a416684f5376b8aaca699e768aa36bcbe22..4379d0bfd05593d8dc8786f64876390ccf08aa8e 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/assign.pass.cpp
@@ -27,7 +27,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/copy.pass.cpp
index 2e141ca9295501de40b67a31d8eda039a4f1628a..60fa5193360b0d8c14a1fb5de6e2ca922336a619 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/copy.pass.cpp
@@ -25,7 +25,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/ctor_double.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/ctor_double.pass.cpp
index d5f86cb03f931804737a53591b17cbac96b3e32a..e27d13331d25db22cab19382f62213b6a813febc 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/ctor_double.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/ctor_double.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::poisson_distribution<> D;
@@ -28,4 +28,6 @@ int main()
         D d(3.5);
         assert(d.mean() == 3.5);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/ctor_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/ctor_param.pass.cpp
index c8ee8414682b2fcf119ccc82e1d092993e156d84..117adb25a5045e8bd895bd166daac423a75891ba 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/ctor_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/ctor_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::poisson_distribution<> D;
@@ -25,4 +25,6 @@ int main()
         D d(p);
         assert(d.mean() == 0.25);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/eq.pass.cpp
index cc7a8bd9d64b4d88ee6ab965ac54afa4ed589bf3..0d7dda0d9725bbef0256df3495e7952db8cef50e 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/eq.pass.cpp
@@ -19,7 +19,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::poisson_distribution<> D;
@@ -33,4 +33,6 @@ int main()
         D d2(.25);
         assert(d1 != d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/eval.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/eval.pass.cpp
index 0e3d1c2e4d0e781686eed06c075b344958aa1137..588eddba2ebc2ae82ce72d50f38138bfa74401e0 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/eval.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/eval.pass.cpp
@@ -28,7 +28,7 @@ sqr(T x)
     return x * x;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::poisson_distribution<> D;
@@ -147,4 +147,6 @@ int main()
         assert(std::abs((skew - x_skew) / x_skew) < 0.01);
         assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.01);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/eval_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/eval_param.pass.cpp
index 27b6a9c39c4df80fa0c6cad45b9ad88562c17a54..67f726843134a235bb976154581a9f3c1439087c 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/eval_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/eval_param.pass.cpp
@@ -28,7 +28,7 @@ sqr(T x)
     return x * x;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::poisson_distribution<> D;
@@ -153,4 +153,6 @@ int main()
         assert(std::abs((skew - x_skew) / x_skew) < 0.01);
         assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.01);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/get_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/get_param.pass.cpp
index 8d2b76df24ca6c7a0080b03e6b7acf45baa0d5c2..a55a3837c7fcc899b931eff45587d8051f3fe83a 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/get_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/get_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::poisson_distribution<> D;
@@ -25,4 +25,6 @@ int main()
         D d(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/io.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/io.pass.cpp
index e8ffce1faf4eb900f42e96760027df1562f195f4..4aec884f6b90babadc481822229aedc0109525ff 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/io.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/io.pass.cpp
@@ -25,7 +25,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::poisson_distribution<> D;
@@ -37,4 +37,6 @@ int main()
         is >> d2;
         assert(d1 == d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/max.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/max.pass.cpp
index 853d70749a3031b41ed30f151814d81ed2d8aa9a..b1cb125084a3f9f2d1ccdca1dca1f58f472e62b2 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/max.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/max.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::poisson_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         D::result_type m = d.max();
         assert(m == std::numeric_limits<int>::max());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/min.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/min.pass.cpp
index da95d9c4cef9532336f24807af87c7dc34c23245..e65319c56c21664633444aae76e37b3b6d47f2c4 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/min.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/min.pass.cpp
@@ -16,11 +16,13 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::poisson_distribution<> D;
         D d(.5);
         assert(d.min() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/param_assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/param_assign.pass.cpp
index 1982ff5dedc99a69b30f6ab59f2be4dc431648e4..393153a7c062119ad9f65cdd1c31a95615a6e524 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/param_assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/param_assign.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::poisson_distribution<> D;
@@ -27,4 +27,6 @@ int main()
         p = p0;
         assert(p.mean() == .7);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/param_copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/param_copy.pass.cpp
index 841c7ddacae7975ede18824924edd3e318ba2cda..a02e7250fc71ffab5b43d91c5df139c9e1d69c90 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/param_copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/param_copy.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::poisson_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         param_type p = p0;
         assert(p.mean() == .125);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/param_ctor.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/param_ctor.pass.cpp
index 8dea424b488e9b5b1b8bf0352c15d0da99bd7874..1e395fdfd22a686dfcdc22f6c057d24b338c1f1c 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/param_ctor.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/param_ctor.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::poisson_distribution<> D;
@@ -31,4 +31,6 @@ int main()
         param_type p(10);
         assert(p.mean() == 10);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/param_eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/param_eq.pass.cpp
index 307a0d08df1930a1afd534d5a760a2c1eb9a6d8f..5e9aa27ccf442f9c0a409e0b1497b716312b382f 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/param_eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/param_eq.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::poisson_distribution<> D;
@@ -33,4 +33,6 @@ int main()
         param_type p2(0.5);
         assert(p1 != p2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/param_types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/param_types.pass.cpp
index c4e1e434a9d015980eaaaa66bb07c02808b4cc55..b81d15cf0be157985aca96494c5e417d2cacbe50 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/param_types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/param_types.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::poisson_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         typedef param_type::distribution_type distribution_type;
         static_assert((std::is_same<D, distribution_type>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/set_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/set_param.pass.cpp
index 406b8472284b50ede0bdc496fdb8255ca07e67cb..d75e6a1daf8e0daff231ba17531e2c9294a33bd2 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/set_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/set_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::poisson_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         d.param(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/types.pass.cpp
index 16165b0b76803c50bd964a4ab51bf3cbc90828a1..982919268be43337340edd3c30d34f17a63deae3 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.poisson/types.pass.cpp
@@ -18,7 +18,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::poisson_distribution<> D;
@@ -30,4 +30,6 @@ int main()
         typedef D::result_type result_type;
         static_assert((std::is_same<result_type, unsigned long long>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/assign.pass.cpp
index c6090b523d93afa1525c25ef287f62316f2e726c..ff81b81208318ab66bf636e76b897e96394400d3 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/assign.pass.cpp
@@ -27,7 +27,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/copy.pass.cpp
index 22d51fc34283a9275ad4a874ee0c2495089d2f97..0cfafa7257a91a2d962a5990c02feba9775f3379 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/copy.pass.cpp
@@ -25,7 +25,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/ctor_double_double.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/ctor_double_double.pass.cpp
index ac093c5f50129a9a3fc9c6498c5040dadb8b7435..3f4d55eb9bd1333e015847635d9699f46ef87290 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/ctor_double_double.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/ctor_double_double.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::weibull_distribution<> D;
@@ -36,4 +36,6 @@ int main()
         assert(d.a() == 14.5);
         assert(d.b() == 5.25);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/ctor_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/ctor_param.pass.cpp
index 4faae698b5e38574c8369952ee43e22ca180142f..e876a2df0e686f3ef6fb950efe4290748047b7db 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/ctor_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/ctor_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::weibull_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         assert(d.a() == 0.25);
         assert(d.b() == 10);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/eq.pass.cpp
index 12a3e2354d81568fc134c5c27c19e70a964b45ff..1de323aef1043a90655107eefe8440cef33a9fa9 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/eq.pass.cpp
@@ -19,7 +19,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::weibull_distribution<> D;
@@ -33,4 +33,6 @@ int main()
         D d2(2.5, 4.5);
         assert(d1 != d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/eval.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/eval.pass.cpp
index 6d086b87d9a8585a502ffceaab1b6568176f9945..88e40b29c548760d5f7dd3fa5517071552d479fd 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/eval.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/eval.pass.cpp
@@ -29,7 +29,7 @@ sqr(T x)
     return x * x;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::weibull_distribution<> D;
@@ -160,4 +160,6 @@ int main()
         assert(std::abs((skew - x_skew) / x_skew) < 0.01);
         assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.03);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/eval_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/eval_param.pass.cpp
index 6142f847d37e4f85c84b6b59e68798c2063187ad..3959f440797d2f97b1a587482f2a9a051cbad522 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/eval_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/eval_param.pass.cpp
@@ -29,7 +29,7 @@ sqr(T x)
     return x * x;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::weibull_distribution<> D;
@@ -166,4 +166,6 @@ int main()
         assert(std::abs((skew - x_skew) / x_skew) < 0.01);
         assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.03);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/get_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/get_param.pass.cpp
index fcc21fb29105bb6f1164fd44ef50e2ed4f01e5eb..c2fbf7b98b9eca077ffca6bb1220836f1a097ed7 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/get_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/get_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::weibull_distribution<> D;
@@ -25,4 +25,6 @@ int main()
         D d(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/io.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/io.pass.cpp
index 7ecc16f57355c00dd7d6e4e1c7b30a0dc6555657..6b4f4e9ddbb6671b21a6c7f483f83088aca212f4 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/io.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/io.pass.cpp
@@ -25,7 +25,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::weibull_distribution<> D;
@@ -37,4 +37,6 @@ int main()
         is >> d2;
         assert(d1 == d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/max.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/max.pass.cpp
index 30b504a9643e36e34ff54cddce7cace11c6a2cee..3d9fe0b357afb5150f48278220f96020d661284e 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/max.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/max.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::weibull_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         D::result_type m = d.max();
         assert(m == INFINITY);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/min.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/min.pass.cpp
index 16a89bcd43c54f083736eab9ee4f7e408f2404d5..f92384041ac43f0c9d9456a646c354679dd97ed0 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/min.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/min.pass.cpp
@@ -16,11 +16,13 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::weibull_distribution<> D;
         D d(.5, .5);
         assert(d.min() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/param_assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/param_assign.pass.cpp
index 3be04f268915c88e8120a35e9ad7d93c3d3c6071..add72f68563e48766e9609cd986ba8b1dcd81ccc 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/param_assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/param_assign.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::weibull_distribution<> D;
@@ -28,4 +28,6 @@ int main()
         assert(p.a() == .75);
         assert(p.b() == 6);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/param_copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/param_copy.pass.cpp
index 800d6302a86acb3df7c0b9d6ecf676be98a01e0a..f2b7e95a4c33c498aeae7c1ed99ab5f4ceb5ab45 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/param_copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/param_copy.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::weibull_distribution<> D;
@@ -27,4 +27,6 @@ int main()
         assert(p.a() == 10);
         assert(p.b() == .125);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/param_ctor.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/param_ctor.pass.cpp
index f88ba354563960f53e2c17a211f9a57aaa1dda9e..6a03330c156288ff169e1a0dde218bc05079dc84 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/param_ctor.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/param_ctor.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::weibull_distribution<> D;
@@ -40,4 +40,6 @@ int main()
         assert(p.a() == 10);
         assert(p.b() == 5);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/param_eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/param_eq.pass.cpp
index 621eda13f54886e4892bcba783589299a1ccf47a..e47f576728c2d7f74f51cbad60dad17b731bd3bc 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/param_eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/param_eq.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::weibull_distribution<> D;
@@ -33,4 +33,6 @@ int main()
         param_type p2(0.5, .5);
         assert(p1 != p2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/param_types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/param_types.pass.cpp
index cd7d5209f50cea332a9d660134990f1a6433e732..08c58d03d1a265975417ae6ea189ec8f5fd8728c 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/param_types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/param_types.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::weibull_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         typedef param_type::distribution_type distribution_type;
         static_assert((std::is_same<D, distribution_type>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/set_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/set_param.pass.cpp
index 05acfd5e6507f54a75e142b570cbc0d405946201..f3c5a20d29e5162d121dd6adbed62cacbbf919ad 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/set_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/set_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::weibull_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         d.param(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/types.pass.cpp
index bd9b474794f294df3f80aad0bd0f78947c73e9df..51b97e081d7fc0a2c5933b197195df4c513feddd 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.pois/rand.dist.pois.weibull/types.pass.cpp
@@ -18,7 +18,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::weibull_distribution<> D;
@@ -30,4 +30,6 @@ int main()
         typedef D::result_type result_type;
         static_assert((std::is_same<result_type, float>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/nothing_to_do.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/assign.pass.cpp
index a6d6822b6f81ef5677ca1138f877183237368d1a..f1d5b3b24c2d7760b6ec336ad1973e206fb02c50 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/assign.pass.cpp
@@ -28,7 +28,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/copy.pass.cpp
index 0b1b7b919c32764ae3d365fcb68bdbf9cf7ebb6d..19f8dc179e2879c4f4282dcb9273817d3ed2e78d 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/copy.pass.cpp
@@ -26,7 +26,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/ctor_default.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/ctor_default.pass.cpp
index 89fc479f2ba053f7db6fff72e9081e37a780f054..f8d769dbda0715b3d8b976005998896bd854da26 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/ctor_default.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/ctor_default.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::discrete_distribution<> D;
@@ -25,4 +25,6 @@ int main()
         assert(p.size() == 1);
         assert(p[0] == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/ctor_func.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/ctor_func.pass.cpp
index 700eb91bae7b6df097431e9fc2969e4170acfaaf..198b845b3e67ed8a1b26765601c5fe94b43b0bd1 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/ctor_func.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/ctor_func.pass.cpp
@@ -23,7 +23,7 @@ double fw(double x)
     return x+1;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::discrete_distribution<> D;
@@ -56,4 +56,6 @@ int main()
         assert(p[1] == .21875);
         assert(p[2] == .28125);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/ctor_init.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/ctor_init.pass.cpp
index 51e43f4d2fec738d0c2be297d04a93f60335afa4..a9c1e2bb42c74bf277119eaf21dfbf0bf7ae961d 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/ctor_init.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/ctor_init.pass.cpp
@@ -18,7 +18,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::discrete_distribution<> D;
@@ -77,4 +77,6 @@ int main()
         assert(p[1] == 0);
         assert(p[2] == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/ctor_iterator.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/ctor_iterator.pass.cpp
index eafbd1b564d624315362bd658da2e4e7a7ae8fa1..66912cf4a94ebbc3937df7d027699f6297980ef2 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/ctor_iterator.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/ctor_iterator.pass.cpp
@@ -17,7 +17,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::discrete_distribution<> D;
@@ -83,4 +83,6 @@ int main()
         assert(p[1] == 0);
         assert(p[2] == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/ctor_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/ctor_param.pass.cpp
index 8a18ab83e279f1e23369aff2706a2a9db3aaa0be..a25c9fbd31c19f2975b6aa6ad2db89cf69e7690a 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/ctor_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/ctor_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::discrete_distribution<> D;
@@ -29,4 +29,6 @@ int main()
         assert(p[0] == 0.25);
         assert(p[1] == 0.75);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/eq.pass.cpp
index 302e171ca08376afd2de8231dcd57bd47ddc0d6d..409cc39ebb14c79fde30031cea66f1e24649b736 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/eq.pass.cpp
@@ -19,7 +19,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::discrete_distribution<> D;
@@ -41,4 +41,6 @@ int main()
         D d2;
         assert(d1 != d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/eval.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/eval.pass.cpp
index 170fc16a7f62722a934bda2e3e7b814d6d20c5c8..5dd70d144fa5e741d0aa4fc005766147096de9a4 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/eval.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/eval.pass.cpp
@@ -19,7 +19,7 @@
 #include <vector>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::discrete_distribution<> D;
@@ -275,4 +275,6 @@ int main()
             else
                 assert(u[i] == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/eval_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/eval_param.pass.cpp
index dbfd5da94bbc0a0c07273e1a1c627e02b88c6a7b..6cc4e90b25eb69d16a1bec020410106791bd5058 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/eval_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/eval_param.pass.cpp
@@ -19,7 +19,7 @@
 #include <vector>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::discrete_distribution<> D;
@@ -41,4 +41,6 @@ int main()
         for (int i = 0; i <= 2; ++i)
             assert(std::abs((double)u[i]/N - prob[i]) / prob[i] < 0.001);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/get_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/get_param.pass.cpp
index 26ef68c66deeb970d34a52a24b2a8d382a382e02..59e33128243fe1a51d4624b26dd9fd529b7519f4 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/get_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/get_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::discrete_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         D d(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/io.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/io.pass.cpp
index 4e95cc477144ccd9ea399bf3c65ad4a9c7eeda23..ff9434c8a16ae14abd1da6b0743cdb4059eb5a42 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/io.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/io.pass.cpp
@@ -25,7 +25,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::discrete_distribution<> D;
@@ -38,4 +38,6 @@ int main()
         is >> d2;
         assert(d1 == d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/max.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/max.pass.cpp
index c6356cf7697b65158f5d83f1e1800ec2edfa515b..d365763914fa64f9db2eab54eb33ffa83a329f22 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/max.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/max.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::discrete_distribution<> D;
@@ -30,4 +30,6 @@ int main()
         D d(p0, p0+4);
         assert(d.max() == 3);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/min.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/min.pass.cpp
index b40c4c513369d4471b48e6e68c20106f0bb67109..259eddc5d023779c76a5e7dccfc94107c34ef6e1 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/min.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/min.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::discrete_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         D d(p0, p0+3);
         assert(d.min() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_assign.pass.cpp
index 23decd2b831b98523556a5b301052befc397f106..c50a2536c2092cef106db98f1e9d0d632b3546bf 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_assign.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::discrete_distribution<> D;
@@ -28,4 +28,6 @@ int main()
         p = p0;
         assert(p == p0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_copy.pass.cpp
index a50a5f4244da70b5f8e95a8a6b781e15490b225b..9b7e6b9edcf6b151f2b45ddada340f78dc73ef75 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_copy.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::discrete_distribution<> D;
@@ -27,4 +27,6 @@ int main()
         param_type p = p0;
         assert(p == p0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_ctor_default.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_ctor_default.pass.cpp
index b915e2cb58b344873a7341756de8e257f909b3d9..680ce405c7e7ff31342dc4a18d814e0768f193be 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_ctor_default.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_ctor_default.pass.cpp
@@ -18,7 +18,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::discrete_distribution<> D;
@@ -28,4 +28,6 @@ int main()
         assert(p.size() == 1);
         assert(p[0] == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_ctor_func.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_ctor_func.pass.cpp
index 8d00e62833446a7513acd86807a6f3f60a56cfdd..4dd919dc4ecdec7f28050350a2578d38548b7775 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_ctor_func.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_ctor_func.pass.cpp
@@ -23,7 +23,7 @@ double fw(double x)
     return x+1;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::discrete_distribution<> D;
@@ -60,4 +60,6 @@ int main()
         assert(p[1] == .21875);
         assert(p[2] == .28125);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_ctor_init.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_ctor_init.pass.cpp
index 69ffe3d4612045e687d2ce28526aade68bca01ef..91adbdb07dae417bdb1d95cac531173f600cbddf 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_ctor_init.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_ctor_init.pass.cpp
@@ -18,7 +18,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::discrete_distribution<> D;
@@ -84,4 +84,6 @@ int main()
         assert(p[1] == 0);
         assert(p[2] == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_ctor_iterator.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_ctor_iterator.pass.cpp
index aa7d6bfb820b57fee480e7a92f2e633b99c3d899..b553ffab127eb4a24c3bc81802f892f265dbc810 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_ctor_iterator.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_ctor_iterator.pass.cpp
@@ -17,7 +17,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::discrete_distribution<> D;
@@ -90,4 +90,6 @@ int main()
         assert(p[1] == 0);
         assert(p[2] == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_eq.pass.cpp
index aac1d00fed810d657935258565a68ade9f8b4cf8..3ca6786933fa98a4797fc672d6b314c5b53585f4 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_eq.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::discrete_distribution<> D;
@@ -35,4 +35,6 @@ int main()
         param_type p2;
         assert(p1 != p2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_types.pass.cpp
index 558f8ad7f7191e6c063dca43e1db553f0e8a47ad..fab19160264cabb3444553ff81cd026e2904e6c1 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/param_types.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::discrete_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         typedef param_type::distribution_type distribution_type;
         static_assert((std::is_same<D, distribution_type>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/set_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/set_param.pass.cpp
index 9334f724563a79314cec292e79ed9c1193d3de47..9858a30a77872aa4bcbd2ac31e2686e3d9774093 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/set_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/set_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::discrete_distribution<> D;
@@ -27,4 +27,6 @@ int main()
         d.param(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/types.pass.cpp
index 99a474a4cf87c5235b46c8192bf70c23777e8ea5..d45475ba36fdd0a18b82479566fe56de130f04e6 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.discrete/types.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::discrete_distribution<> D;
@@ -28,4 +28,6 @@ int main()
         typedef D::result_type result_type;
         static_assert((std::is_same<result_type, long>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/assign.pass.cpp
index 1de6fd363ec46dd860133bc140a41eafab0581c8..3b63601aee9f5e4bc9b55604ee2b1037990d7714 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/assign.pass.cpp
@@ -29,7 +29,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/copy.pass.cpp
index 6d8e36ef3dc92b306e306dcc8e6fc3c22d548f06..82b0d8ef3f93552f0eee799659fd132993359b98 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/copy.pass.cpp
@@ -27,7 +27,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/ctor_default.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/ctor_default.pass.cpp
index f05cd9941f79bc4255e70eb664ce73d4c638c2b4..836b690082a934e813c89433eff68d3ff6c62fd4 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/ctor_default.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/ctor_default.pass.cpp
@@ -18,7 +18,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_constant_distribution<> D;
@@ -31,4 +31,6 @@ int main()
         assert(dn.size() == 1);
         assert(dn[0] == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/ctor_func.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/ctor_func.pass.cpp
index 7c8ae7fa88a166a3af986500066accffd8b300de..7e7537ad8049127e9e34cd6d0007dca4a282ee93 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/ctor_func.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/ctor_func.pass.cpp
@@ -23,7 +23,7 @@ double fw(double x)
     return 2*x;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_constant_distribution<> D;
@@ -60,4 +60,6 @@ int main()
         assert(dn[0] == 0.1);
         assert(dn[1] == 0.15);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/ctor_init_func.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/ctor_init_func.pass.cpp
index f86cbf56c4c4108794c4ccbfd439497f874220e5..22c8a1f4ef27a831676b0de6edd30ef1de32a65d 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/ctor_init_func.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/ctor_init_func.pass.cpp
@@ -26,7 +26,7 @@ double f(double x)
     return x*2;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_constant_distribution<> D;
@@ -74,4 +74,6 @@ int main()
         assert(dn[0] == 0.203125);
         assert(dn[1] == 0.1484375);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/ctor_iterator.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/ctor_iterator.pass.cpp
index 463e78c850ab3376da86256ad2dd7e74a917f8f6..695a7ba5f1686ee5239e0d34923d83b1d3a23e3b 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/ctor_iterator.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/ctor_iterator.pass.cpp
@@ -19,7 +19,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_constant_distribution<> D;
@@ -92,4 +92,6 @@ int main()
         assert(dn[1] == .3125);
         assert(dn[2] == .125);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/ctor_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/ctor_param.pass.cpp
index e9439d2933d1ca00bda5bde027bf7490dbe2687e..1a10bb31b3608a70d913d73c87fb1236a46f5dcd 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/ctor_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/ctor_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_constant_distribution<> D;
@@ -37,4 +37,6 @@ int main()
         assert(dn[1] == .3125);
         assert(dn[2] == .125);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/eq.pass.cpp
index 7cd8b1e069e6051b51c166649b39236405065bcd..18b5d59bd108c8de5bfe9889481a45489f24a2f2 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/eq.pass.cpp
@@ -19,7 +19,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_constant_distribution<> D;
@@ -43,4 +43,6 @@ int main()
         D d2;
         assert(d1 != d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/eval.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/eval.pass.cpp
index 048fb2d2221e4fda2fe08139c2de8f3593023768..d00be22e551b9884818d83860f403f22fbd781ea 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/eval.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/eval.pass.cpp
@@ -723,7 +723,7 @@ test11()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
@@ -736,4 +736,6 @@ int main()
     test9();
     test10();
     test11();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/eval_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/eval_param.pass.cpp
index 0d0e6e50d8a4338ef8c56adc71fdaa8a7837c862..c82a6b8515aa145ac28d6369f482f8a47f29d605 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/eval_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/eval_param.pass.cpp
@@ -31,7 +31,7 @@ sqr(T x)
     return x*x;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_constant_distribution<> D;
@@ -95,4 +95,6 @@ int main()
             }
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/get_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/get_param.pass.cpp
index b842d2433f8b79416cf3e3f29b842cbbad834ccf..90f469480d9a621d0171f4a3f560d8e85c96156b 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/get_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/get_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_constant_distribution<> D;
@@ -28,4 +28,6 @@ int main()
         D d(pa);
         assert(d.param() == pa);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/io.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/io.pass.cpp
index e4748c15e5cb188f62b550853cf82bc724c44721..b22fdfa584086082ab4ec1c7869e7023ccc817be 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/io.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/io.pass.cpp
@@ -25,7 +25,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_constant_distribution<> D;
@@ -40,4 +40,6 @@ int main()
         is >> d2;
         assert(d1 == d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/max.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/max.pass.cpp
index 7de0052dfb7480f2b8fd51f4c0c3cd0f7a39194b..19c11c66f229a2aa4e77893eb20497eb1a9ccb10 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/max.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/max.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_constant_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         D d(b, b+Np+1, p);
         assert(d.max() == 17);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/min.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/min.pass.cpp
index 601eeecc4ca65bb06a78d1149dd90b7b3215b119..8a5fe519fb623d8f85ec0d484c7f8b31f77d8486 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/min.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/min.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_constant_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         D d(b, b+Np+1, p);
         assert(d.min() == 10);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_assign.pass.cpp
index 87d78547a5541aa1c1903c70aba281bdbaddb6b3..7c42c738c145bbed80b1346bddb4b7b1fd4c8bc2 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_assign.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_constant_distribution<> D;
@@ -30,4 +30,6 @@ int main()
         p1 = p0;
         assert(p1 == p0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_copy.pass.cpp
index b9a22a15340090a9b9010deebc2932cddac6f32f..f9eec8d731f0143e49d2b82b4c24d6c233de417f 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_copy.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_constant_distribution<> D;
@@ -29,4 +29,6 @@ int main()
         P p1 = p0;
         assert(p1 == p0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_ctor_default.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_ctor_default.pass.cpp
index 4b3dad0af47bc18e0ce3b6e89aee0ac394918186..ac2f724b08ed309a41d4962177a5916f0b26b3f3 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_ctor_default.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_ctor_default.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_constant_distribution<> D;
@@ -30,4 +30,6 @@ int main()
         assert(dn.size() == 1);
         assert(dn[0] == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_ctor_func.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_ctor_func.pass.cpp
index a8adb5be1c0459ee9eeb114798725eb3b3fc12e4..d14a50817c63c63fb69c646ec75d4b653c770569 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_ctor_func.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_ctor_func.pass.cpp
@@ -23,7 +23,7 @@ double fw(double x)
     return 2*x;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_constant_distribution<> D;
@@ -63,4 +63,6 @@ int main()
         assert(dn[0] == 0.1);
         assert(dn[1] == 0.15);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_ctor_init_func.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_ctor_init_func.pass.cpp
index 20a2cdbdcb2a86edec5d467becdc6e3a3a9e3c59..b7e5a49639e5c7f2a255251dae91d5d48ee3e744 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_ctor_init_func.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_ctor_init_func.pass.cpp
@@ -23,7 +23,7 @@ double f(double x)
     return x*2;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_constant_distribution<> D;
@@ -75,4 +75,6 @@ int main()
         assert(dn[0] == 0.203125);
         assert(dn[1] == 0.1484375);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_ctor_iterator.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_ctor_iterator.pass.cpp
index 2b11672e263a857ea6be7847f0929de4c6344da3..96dda54d2465af4b1cb60a8a5855545c9c1b737d 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_ctor_iterator.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_ctor_iterator.pass.cpp
@@ -18,7 +18,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_constant_distribution<> D;
@@ -96,4 +96,6 @@ int main()
         assert(dn[1] == .3125);
         assert(dn[2] == .125);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_eq.pass.cpp
index c3fe7c42b874a15ca4600c6d152fc3e82a41b608..4571613f98791d8b493ebf203a427786194dd68a 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_eq.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_constant_distribution<> D;
@@ -37,4 +37,6 @@ int main()
         P p2(b, b+4, p);
         assert(p1 != p2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_types.pass.cpp
index 99132cdd8edd43971009c58cfb6ec91509fb3a6b..3d4c25e882a61026a60932fd5c42233dfe77f92f 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/param_types.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_constant_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         typedef param_type::distribution_type distribution_type;
         static_assert((std::is_same<D, distribution_type>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/set_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/set_param.pass.cpp
index b87bd85bc2c1645ab099bb073b01e48186193c90..a34187cb2cecdaf89a0a9b449e18b5d45115ffd4 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/set_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/set_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_constant_distribution<> D;
@@ -28,4 +28,6 @@ int main()
         d.param(pa);
         assert(d.param() == pa);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/types.pass.cpp
index bfc3cb774994fb054c26ce40bc8b5d9f25c29493..eec866112d8cfbf2c0dc30c483c556154e8b24d8 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.pconst/types.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_constant_distribution<> D;
@@ -28,4 +28,6 @@ int main()
         typedef D::result_type result_type;
         static_assert((std::is_same<result_type, float>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/assign.pass.cpp
index d150c8668ed1bbbf50ae61ef7434d73c901efdd3..ff478a05b79aaeda8d65b4cf21beb1f42a8ed5f2 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/assign.pass.cpp
@@ -29,7 +29,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/copy.pass.cpp
index bb87e31136e42f94003ff6eece2eb559cffc4f8a..ba5e6d59a17a96b6a0719c3eb040e432314d98f1 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/copy.pass.cpp
@@ -27,7 +27,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/ctor_default.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/ctor_default.pass.cpp
index f96a044a48838446bf0bda1eee9b10ab9d6f39fb..ded81c974fca73e5bd03044c2e3131b87d637083 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/ctor_default.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/ctor_default.pass.cpp
@@ -18,7 +18,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_linear_distribution<> D;
@@ -32,4 +32,6 @@ int main()
         assert(dn[0] == 1);
         assert(dn[1] == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/ctor_func.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/ctor_func.pass.cpp
index fd42c225647c168e2c078e0c7199d41aa28d614f..175774dc00677222274d85e2c7e75b0e054d6bb9 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/ctor_func.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/ctor_func.pass.cpp
@@ -25,7 +25,7 @@ double fw(double x)
     return 2*x;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_linear_distribution<> D;
@@ -65,4 +65,6 @@ int main()
         assert(dn[1] == 0.125);
         assert(dn[2] == 0.175);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/ctor_init_func.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/ctor_init_func.pass.cpp
index e4db52bc952783a31c83db51f725fb0d4a72b317..ab29fecf6154df50a091a691c35f0b006deafd6c 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/ctor_init_func.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/ctor_init_func.pass.cpp
@@ -26,7 +26,7 @@ double f(double x)
     return x*2;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_linear_distribution<> D;
@@ -78,4 +78,6 @@ int main()
         assert(dn[1] == 0.125);
         assert(dn[2] == 0.175);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/ctor_iterator.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/ctor_iterator.pass.cpp
index 13517e1cc9fc381f2682583e9f71b98e9572e22e..541976ad1d54a14ed12d4b5c788401e46cb28c62 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/ctor_iterator.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/ctor_iterator.pass.cpp
@@ -19,7 +19,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_linear_distribution<> D;
@@ -97,4 +97,6 @@ int main()
         assert(dn[2] == 1/4.5);
         assert(dn[3] == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/ctor_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/ctor_param.pass.cpp
index 2592763cfa63d168e1e77f8b3a91a516db1d0486..1ecbe87c20db42975cf8704047d8a31ffccd9b50 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/ctor_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/ctor_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_linear_distribution<> D;
@@ -38,4 +38,6 @@ int main()
         assert(dn[2] == 12.5/256.25);
         assert(dn[3] == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/eq.pass.cpp
index 019335ee72e070d44364c5c054c6cb645256397f..19eda7357b20dd05144ba226e01b94751a678cca 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/eq.pass.cpp
@@ -19,7 +19,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_linear_distribution<> D;
@@ -43,4 +43,6 @@ int main()
         D d2;
         assert(d1 != d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/eval.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/eval.pass.cpp
index 1aab615ad0e7e4983c9f9733e5b08bf33ee8d40a..6476f3567ff0e6f1593d9d6e219489a86d3fca08 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/eval.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/eval.pass.cpp
@@ -354,7 +354,7 @@ test6()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
@@ -362,4 +362,6 @@ int main()
     test4();
     test5();
     test6();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/eval_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/eval_param.pass.cpp
index 11f2c492685d83f743dcae4b5688bca0ef020f74..621320ca49e03e2200761f8e74ff503d9a88ba15 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/eval_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/eval_param.pass.cpp
@@ -37,7 +37,7 @@ f(double x, double a, double m, double b, double c)
     return a + m*(sqr(x) - sqr(b))/2 + c*(x-b);
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_linear_distribution<> D;
@@ -90,4 +90,6 @@ int main()
             assert(std::abs(f(u[i], a, m, bk, c) - double(i)/N) < .001);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/get_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/get_param.pass.cpp
index 56e648f50f79fd255cc4cb4a1047f0f77c2fe0c3..7776330c04979dc89b577a0faf46ae130ab668f0 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/get_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/get_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_linear_distribution<> D;
@@ -28,4 +28,6 @@ int main()
         D d(pa);
         assert(d.param() == pa);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/io.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/io.pass.cpp
index 845b64a9f3731c5dd61e818ec401a36c82e498d2..258fdb77b8324ca4e8e25767a22b251c87f80280 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/io.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/io.pass.cpp
@@ -25,7 +25,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_linear_distribution<> D;
@@ -40,4 +40,6 @@ int main()
         is >> d2;
         assert(d1 == d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/max.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/max.pass.cpp
index aa46f40b019b89e2b5bf529a0c755cbc95f71961..ea6530eae00869902942b6b2f9c3081b83fdd06c 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/max.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/max.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_linear_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         D d(b, b+Np, p);
         assert(d.max() == 17);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/min.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/min.pass.cpp
index 28a1b68f208f85593345637a370da777e68e80a8..80c77d6e32727b5d8de5d9ec8d480705ddfd99b3 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/min.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/min.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_linear_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         D d(b, b+Np, p);
         assert(d.min() == 10);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_assign.pass.cpp
index 3534a8935a1aaf5231c4ffcdaa3a082135c1355b..145e616306d53c7b745f9664bc9b8907c6a97507 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_assign.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_linear_distribution<> D;
@@ -30,4 +30,6 @@ int main()
         p1 = p0;
         assert(p1 == p0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_copy.pass.cpp
index 8d784c66969ab6d4845e4ea8b98c3308c24c8347..b409f58f08ec74acf1d64663cae19b78defa0b82 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_copy.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_linear_distribution<> D;
@@ -29,4 +29,6 @@ int main()
         P p1 = p0;
         assert(p1 == p0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_ctor_default.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_ctor_default.pass.cpp
index 5d543cf5973eb5c5457e73f5bab790d9375e14bc..69d4d71f4e4f9d2354131852a1d0b5138ab52728 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_ctor_default.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_ctor_default.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_linear_distribution<> D;
@@ -31,4 +31,6 @@ int main()
         assert(dn[0] == 1);
         assert(dn[1] == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_ctor_func.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_ctor_func.pass.cpp
index 48e34c743c029effa914f22358a0515c9af94c2a..c6ea33b1f15f92f8cab84e9257a481dec671be86 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_ctor_func.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_ctor_func.pass.cpp
@@ -23,7 +23,7 @@ double fw(double x)
     return 2*x;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_linear_distribution<> D;
@@ -66,4 +66,6 @@ int main()
         assert(dn[1] == 0.125);
         assert(dn[2] == 0.175);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_ctor_init_func.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_ctor_init_func.pass.cpp
index cff26c592b8d717fb4448fef8a2d97f0ee1764a6..3972715d0afb0cd217462dbc0f663a6d95cbb53a 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_ctor_init_func.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_ctor_init_func.pass.cpp
@@ -23,7 +23,7 @@ double f(double x)
     return x*2;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_linear_distribution<> D;
@@ -79,4 +79,6 @@ int main()
         assert(dn[1] == 0.125);
         assert(dn[2] == 0.175);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_ctor_iterator.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_ctor_iterator.pass.cpp
index 61122d6f625734b6851bb02e290a04de975651e2..4a51902a00f4d9070287040a53c30b1f9b672877 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_ctor_iterator.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_ctor_iterator.pass.cpp
@@ -18,7 +18,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_linear_distribution<> D;
@@ -101,4 +101,6 @@ int main()
         assert(dn[2] == 1/4.5);
         assert(dn[3] == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_eq.pass.cpp
index aab37f7bacbb93b8f557d99b60437bc157a06f62..e7a15d683059d5e793d748df5b52ee5eb95ddaa6 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_eq.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_linear_distribution<> D;
@@ -37,4 +37,6 @@ int main()
         P p2(b, b+4, p);
         assert(p1 != p2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_types.pass.cpp
index 0907745d874cfc88b03a60fa6519fa418ca4c235..f6d65ddcc8e7711f19ca0787b59b9181d5f82ac5 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/param_types.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_linear_distribution<> D;
@@ -24,4 +24,6 @@ int main()
         typedef param_type::distribution_type distribution_type;
         static_assert((std::is_same<D, distribution_type>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/set_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/set_param.pass.cpp
index ff96a86573bc6dfc03d94291b2229fc091283bae..c5697d7ce6485f0abc49f9fd0c6f1c0c8cdcc48c 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/set_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/set_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_linear_distribution<> D;
@@ -28,4 +28,6 @@ int main()
         d.param(pa);
         assert(d.param() == pa);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/types.pass.cpp
index d53117395c40f97b6e6e8e2879d6e09281301912..9d8bdf6fca13ddb91e261139bf964958543323be 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.samp/rand.dist.samp.plinear/types.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::piecewise_linear_distribution<> D;
@@ -28,4 +28,6 @@ int main()
         typedef D::result_type result_type;
         static_assert((std::is_same<result_type, float>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/nothing_to_do.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/assign.pass.cpp
index 9c4d970b2a6e7af0091979424c13a1e3e9887740..e34abf08899ed5db235ff24244c68cee27c6f6d7 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/assign.pass.cpp
@@ -27,7 +27,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/copy.pass.cpp
index 8ddf2f0b37010f0b66ed7d4ef49414bbd1ea0bac..796aebacc7dbe26bdd4d44cf8cc1afe884cb9636 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/copy.pass.cpp
@@ -25,7 +25,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/ctor_int_int.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/ctor_int_int.pass.cpp
index edbc060d0382747d1b738ca1b305736ebd8636db..8a4fd33589ba7fff84ee113fbfad144bebc07c92 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/ctor_int_int.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/ctor_int_int.pass.cpp
@@ -17,7 +17,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_int_distribution<> D;
@@ -37,4 +37,6 @@ int main()
         assert(d.a() == -6);
         assert(d.b() == 106);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/ctor_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/ctor_param.pass.cpp
index c462f279cb0c116bf967a5b891b68e5119659d1c..2546810ec57166cf5b2d54feaf2734074a9ac4b6 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/ctor_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/ctor_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_int_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         assert(d.a() == 3);
         assert(d.b() == 8);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/eq.pass.cpp
index d1614923eb8a595caa91825f2354d37a1f63f48c..47e1c89532d49b4be4e4c888297eff9e05f2b20f 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/eq.pass.cpp
@@ -19,7 +19,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_int_distribution<> D;
@@ -33,4 +33,6 @@ int main()
         D d2(3, 9);
         assert(d1 != d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/eval.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/eval.pass.cpp
index 9056a983b2272d9e98c20515fc6b5f57fe699b95..a4e769bd77e65cad27bd27f01e50b475047caa66 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/eval.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/eval.pass.cpp
@@ -29,7 +29,7 @@ sqr(T x)
     return x * x;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_int_distribution<> D;
@@ -452,4 +452,6 @@ int main()
         assert(std::abs(skew - x_skew) < 0.01);
         assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.01);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/eval_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/eval_param.pass.cpp
index 3d4524ca18f895306a34d8e390545b6e7913cfef..77257a8656a824ae71fe2af3fc947aaba87a2539 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/eval_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/eval_param.pass.cpp
@@ -27,7 +27,7 @@ sqr(T x)
     return x * x;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_int_distribution<> D;
@@ -72,4 +72,6 @@ int main()
         assert(std::abs(skew - x_skew) < 0.01);
         assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.01);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/get_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/get_param.pass.cpp
index 199d9a5b24ac873676d628295136bf1846bb83ac..62d144fe5952878c8c256ae1696468ab1d3900c3 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/get_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/get_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_int_distribution<> D;
@@ -25,4 +25,6 @@ int main()
         D d(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/io.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/io.pass.cpp
index 2205a3f479c23320b4e1aa6c5adca5fd0447cfd2..3e029696508e66629bb84373c1cb759f8b084918 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/io.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/io.pass.cpp
@@ -25,7 +25,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_int_distribution<> D;
@@ -37,4 +37,6 @@ int main()
         is >> d2;
         assert(d1 == d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/max.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/max.pass.cpp
index cd196ee15fa7b40c59a624cca393d14deee8e5b4..58ac8571f5b1169a3da4573c977af05a05a7e47c 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/max.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/max.pass.cpp
@@ -16,11 +16,13 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_int_distribution<> D;
         D d(3, 8);
         assert(d.max() == 8);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/min.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/min.pass.cpp
index d1b79a7ff6d675113e4f86dd7f2366396f999819..18b9b50457293e6b9a42a7560ad74d8017f7bc66 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/min.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/min.pass.cpp
@@ -16,11 +16,13 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_int_distribution<> D;
         D d(3, 8);
         assert(d.min() == 3);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/param_assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/param_assign.pass.cpp
index eeb8e635cbfbea124899ba6c08a3c97914e3f416..33d677a91312e8e98ba1848874eaa05c41e9e800 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/param_assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/param_assign.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_int_distribution<long> D;
@@ -28,4 +28,6 @@ int main()
         assert(p.a() == 5);
         assert(p.b() == 10);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/param_copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/param_copy.pass.cpp
index 33f49ede48599d79650089ff56bf6fc0e8b1e55b..1eae36b9632f096e4ed579c1af1d95432931d39f 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/param_copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/param_copy.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_int_distribution<long> D;
@@ -27,4 +27,6 @@ int main()
         assert(p.a() == 5);
         assert(p.b() == 10);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/param_ctor.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/param_ctor.pass.cpp
index da9c08ae8f8a3b22a8aed43944158e3b39573641..6fbf499ca5e2c197daf32b7f1d3b93c87f919530 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/param_ctor.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/param_ctor.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_int_distribution<long> D;
@@ -40,4 +40,6 @@ int main()
         assert(p.a() == 5);
         assert(p.b() == 10);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/param_eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/param_eq.pass.cpp
index 7f76fcc0a8decde0d7f603375ebd95ed3631fa43..b58a965676a56391409be29b52666873dbcc8e16 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/param_eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/param_eq.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_int_distribution<long> D;
@@ -33,4 +33,6 @@ int main()
         param_type p2(6, 10);
         assert(p1 != p2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/param_types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/param_types.pass.cpp
index 84af7f98d556d1c2d339db57560eb6de5b954e1f..b4844a64b01bd63ec045893d82796c452a18d926 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/param_types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/param_types.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_int_distribution<long> D;
@@ -24,4 +24,6 @@ int main()
         typedef param_type::distribution_type distribution_type;
         static_assert((std::is_same<D, distribution_type>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/set_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/set_param.pass.cpp
index a67791f3fb6bc31c5220cbb66be2d9426304d4c5..59b7b0728b5e934b0a933068fbf0899f89a3e220 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/set_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/set_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_int_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         d.param(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/types.pass.cpp
index 5cd31e5f6683e4fcbedbbee51ba068ba5adf2e66..60ff1cb3303a6fed55886827d53d23e6a663ca28 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.int/types.pass.cpp
@@ -16,11 +16,13 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_int_distribution<long> D;
         typedef D::result_type result_type;
         static_assert((std::is_same<result_type, long>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/assign.pass.cpp
index ebdfd0292e4615fd1905d6699db56f08e7a95a13..e348c04ed60dc50c1c7dbc6c97c88de856ba7e32 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/assign.pass.cpp
@@ -27,7 +27,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/copy.pass.cpp
index d53952ccf7237ed7d2c7034d3e499c605e6bf5ec..4fcc9efc3e6a87c49c345094f122f21a07db2237 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/copy.pass.cpp
@@ -25,7 +25,9 @@ test1()
     assert(d1 == d2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/ctor_int_int.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/ctor_int_int.pass.cpp
index 8cb0a1f4318b3b83ffb289161ebf75ca117a3149..c252c5bbbe34e80a489f9f5a453749d64a112bdb 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/ctor_int_int.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/ctor_int_int.pass.cpp
@@ -17,7 +17,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_real_distribution<> D;
@@ -37,4 +37,6 @@ int main()
         assert(d.a() == -6);
         assert(d.b() == 106);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/ctor_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/ctor_param.pass.cpp
index b2913b7722cbe540b8d18fc2b113f5cf22ce51bb..20df543ea3def7bb02f4578dd94a232c695ab3ae 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/ctor_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/ctor_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_real_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         assert(d.a() == 3.5);
         assert(d.b() == 8);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/eq.pass.cpp
index ef0eecafdb367a729f778a15b33df5e0c029a688..fb318626d552952697fb9439f8739e5c0fe48db2 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/eq.pass.cpp
@@ -19,7 +19,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_real_distribution<> D;
@@ -33,4 +33,6 @@ int main()
         D d2(3, 8.1);
         assert(d1 != d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/eval.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/eval.pass.cpp
index aaffa8035dbf2e132ff12f5d74e39856f599f4c5..99fe1f825ecaf6e10fcaec2406721b08624a0208 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/eval.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/eval.pass.cpp
@@ -29,7 +29,7 @@ sqr(T x)
     return x * x;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_real_distribution<> D;
@@ -471,4 +471,6 @@ int main()
         assert(std::abs(skew - x_skew) < 0.01);
         assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.01);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/eval_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/eval_param.pass.cpp
index 79763903b2f8fba988f5bc7c90550a9ddd3aafe0..495f0e9c34a1a5d840b097d990fcbc94a5d45102 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/eval_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/eval_param.pass.cpp
@@ -27,7 +27,7 @@ sqr(T x)
     return x * x;
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_real_distribution<> D;
@@ -71,4 +71,6 @@ int main()
         assert(std::abs(skew - x_skew) < 0.01);
         assert(std::abs((kurtosis - x_kurtosis) / x_kurtosis) < 0.01);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/get_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/get_param.pass.cpp
index 58918c24f22e09b9703bee765624782bca35b10a..b60375545258082227534f4d3f278667a260d296 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/get_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/get_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_real_distribution<> D;
@@ -25,4 +25,6 @@ int main()
         D d(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/io.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/io.pass.cpp
index afea0a72037cf101ea8ef24bbbcfc48751b16e6e..1f6eb580657a61d966fa52052c7b90704238eaf2 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/io.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/io.pass.cpp
@@ -25,7 +25,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_real_distribution<> D;
@@ -37,4 +37,6 @@ int main()
         is >> d2;
         assert(d1 == d2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/max.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/max.pass.cpp
index ecda47ac3c09d7c25d9d04a8d4d0de9d4fa63621..ea75181f80ea12f71553060aeb8a079813a0b8ed 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/max.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/max.pass.cpp
@@ -16,11 +16,13 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_real_distribution<> D;
         D d(3, 8);
         assert(d.max() == 8);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/min.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/min.pass.cpp
index 77545c8f2e484f99a561b5b58854b10d336c35fd..46455e8b416640ee91ce01de6e78b3de0f71801c 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/min.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/min.pass.cpp
@@ -16,11 +16,13 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_real_distribution<> D;
         D d(3, 8);
         assert(d.min() == 3);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/param_assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/param_assign.pass.cpp
index 1575b7feb5209df895f25508ff6d3aae248c6a98..ab4d5969377d499c537812c40b2fc4adc87359f3 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/param_assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/param_assign.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_real_distribution<float> D;
@@ -28,4 +28,6 @@ int main()
         assert(p.a() == 5);
         assert(p.b() == 10);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/param_copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/param_copy.pass.cpp
index 9510b2bd518eb728699606f6e970b1d4c414404e..24260405cfc491ed240c113776c67213a2d39b96 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/param_copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/param_copy.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_real_distribution<float> D;
@@ -27,4 +27,6 @@ int main()
         assert(p.a() == 5);
         assert(p.b() == 10);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/param_ctor.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/param_ctor.pass.cpp
index 67dc714e49ace8978126e68e6c1d0a0cf53f553a..15cad423ef00b9ace9dea007fcdd167a878f957a 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/param_ctor.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/param_ctor.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_real_distribution<float> D;
@@ -40,4 +40,6 @@ int main()
         assert(p.a() == 5);
         assert(p.b() == 10);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/param_eq.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/param_eq.pass.cpp
index e9ee0056420dd87b5d1d127ae72810b3b3946ab9..2127aebf482a0bc494500de8c3bd48afc3bbb270 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/param_eq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/param_eq.pass.cpp
@@ -17,7 +17,7 @@
 #include <limits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_real_distribution<float> D;
@@ -33,4 +33,6 @@ int main()
         param_type p2(6, 10);
         assert(p1 != p2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/param_types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/param_types.pass.cpp
index 5c5ad23315433cc3a2bfb3f87c98c5eb38f11ddf..d2677580e346ab4da7e35fafb15a3f74fb933bd4 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/param_types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/param_types.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_real_distribution<float> D;
@@ -24,4 +24,6 @@ int main()
         typedef param_type::distribution_type distribution_type;
         static_assert((std::is_same<D, distribution_type>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/set_param.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/set_param.pass.cpp
index 021404ba40e646004c181d402afb38a991ed2dd6..f651d72d1b618cf0d93d51f197e07859ec31946b 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/set_param.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/set_param.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_real_distribution<> D;
@@ -26,4 +26,6 @@ int main()
         d.param(p);
         assert(d.param() == p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/types.pass.cpp b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/types.pass.cpp
index 5b75a06570bc2aebb96af3f093a224cc750fd8f8..431b7374a0bd48c7945893a4a89c0de26bff59e7 100644
--- a/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.dis/rand.dist.uni/rand.dist.uni.real/types.pass.cpp
@@ -16,11 +16,13 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::uniform_real_distribution<float> D;
         typedef D::result_type result_type;
         static_assert((std::is_same<result_type, float>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/nothing_to_do.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/assign.pass.cpp
index 313f4278d79f510dbb23fee0f2a20ba221a5b8c2..cfaad1a33a5a9c74465349215e0e442313c90042 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/assign.pass.cpp
@@ -48,10 +48,12 @@ test()
     test1<T, M-1, M-1, M>();
 }
 
-int main()
+int main(int, char**)
 {
     test<unsigned short>();
     test<unsigned int>();
     test<unsigned long>();
     test<unsigned long long>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/copy.pass.cpp
index c49d361787a059a462d2b9c643419ecd3bd68a1d..35585423442edb4d24d4a08e2f8a852c6d6e9adc 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/copy.pass.cpp
@@ -48,10 +48,12 @@ test()
     test1<T, M-1, M-1, M>();
 }
 
-int main()
+int main(int, char**)
 {
     test<unsigned short>();
     test<unsigned int>();
     test<unsigned long>();
     test<unsigned long long>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/ctor_result_type.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/ctor_result_type.pass.cpp
index 97d2ef2d290579fda919bc6ea28feadf2ec958e6..4f2da2f612ad62186c146b21221ca696453d60c4 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/ctor_result_type.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/ctor_result_type.pass.cpp
@@ -129,7 +129,7 @@ test4()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test1<unsigned short>();
     test1<unsigned int>();
@@ -150,4 +150,6 @@ int main()
     test4<unsigned int>();
     test4<unsigned long>();
     test4<unsigned long long>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/ctor_sseq.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/ctor_sseq.pass.cpp
index a489bcd18da72134029bce8fe9d88700eb907bcc..7e82f6395f93167ccd111e85efde98fe4e7bad12 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/ctor_sseq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/ctor_sseq.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         unsigned a[] = {3, 5, 7};
@@ -25,4 +25,6 @@ int main()
         std::linear_congruential_engine<unsigned, 5, 7, 11> e2(4);
         assert(e1 == e2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/default.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/default.pass.cpp
index 67846b06dd28b7d00c4ab54f180aca260ea999ca..372d98a656c71099e9858ba2b993e4706d283d9c 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/default.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/default.pass.cpp
@@ -46,10 +46,12 @@ test()
     test1<T, M-1, M-1, M>();
 }
 
-int main()
+int main(int, char**)
 {
     test<unsigned short>();
     test<unsigned int>();
     test<unsigned long>();
     test<unsigned long long>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/discard.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/discard.pass.cpp
index 4848a3d76f6e31bc84ab8dd4244abcefaec2199c..dcbb3e0656be2df841dce7a771385291701bb4c2 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/discard.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/discard.pass.cpp
@@ -56,7 +56,7 @@ other()
     assert(e1 == e2);
 }
 
-int main()
+int main(int, char**)
 {
     rand0<unsigned int>();
     rand0<unsigned long>();
@@ -69,4 +69,6 @@ int main()
     other<unsigned int>();
     other<unsigned long>();
     other<unsigned long long>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/eval.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/eval.pass.cpp
index ec217f306f09ca20f3be40d29f029120f02b110e..3ee4d9113acebdc85993a4bb7abc1be2236eea4b 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/eval.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/eval.pass.cpp
@@ -70,7 +70,7 @@ Haldir()
     assert(e() == 217250280);
 }
 
-int main()
+int main(int, char**)
 {
     randu<unsigned int>();
     randu<unsigned long>();
@@ -83,4 +83,6 @@ int main()
     Haldir<unsigned int>();
     Haldir<unsigned long>();
     Haldir<unsigned long long>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/io.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/io.pass.cpp
index 04159baa5d7a8f2a3e4ec96a1c426eaa3535fe22..b12de7b0190361e93a1cb56d3f3bd739e14f3d24 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/io.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/io.pass.cpp
@@ -27,7 +27,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::linear_congruential_engine<unsigned, 48271, 0, 2147483647> E;
@@ -40,4 +40,6 @@ int main()
         is >> e2;
         assert(e1 == e2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/result_type.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/result_type.pass.cpp
index 569e76050b32244448d82ebbfc62d039680710c6..e0bb2e02cc17a5f59a1c86a19c0c92c121171637 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/result_type.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/result_type.pass.cpp
@@ -27,10 +27,12 @@ test()
         T>::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     test<unsigned short>();
     test<unsigned int>();
     test<unsigned long>();
     test<unsigned long long>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/seed_result_type.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/seed_result_type.pass.cpp
index da944061bff402a5350044921fdd5dc453a33392..3103bf7efb521943a8dccbaead7f9de5821a2f65 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/seed_result_type.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/seed_result_type.pass.cpp
@@ -30,10 +30,12 @@ test1()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test1<unsigned short>();
     test1<unsigned int>();
     test1<unsigned long>();
     test1<unsigned long long>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/seed_sseq.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/seed_sseq.pass.cpp
index c3aec15f6d58e7087276be5c313a31b9bc7fba9f..e7725bd0b581ac612af070cbd00f9b88a6e4b303 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/seed_sseq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/seed_sseq.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         unsigned a[] = {3, 5, 7};
@@ -35,4 +35,6 @@ int main()
         E e2(sseq);
         assert(e1 == e2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/values.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/values.pass.cpp
index b649b24bb4cdd3f813f7d8f347f3ea590d7362fe..a8c86bad30679bccc1c6214a15e58cc32b796553 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/values.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.lcong/values.pass.cpp
@@ -85,10 +85,12 @@ test()
     test1<T, M-1, M-1, M>();
 }
 
-int main()
+int main(int, char**)
 {
     test<unsigned short>();
     test<unsigned int>();
     test<unsigned long>();
     test<unsigned long long>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/assign.pass.cpp
index 3ac6d303296f5d04b2e418c8a31da93e53a33c83..3e1002b061eb6037b8dc4491ab9e21a6b9273c56 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/assign.pass.cpp
@@ -50,8 +50,10 @@ test2()
     assert(e1 == e2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/copy.pass.cpp
index eb0486aa784ed183a3cea659e01d8e34a26c0865..b1273f1bbc32d67f78d3bf80700d3195bd4e94d9 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/copy.pass.cpp
@@ -48,8 +48,10 @@ test2()
     assert(e1 == e2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/ctor_result_type.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/ctor_result_type.pass.cpp
index ae89e6e79e7f49f9e63fcca0643eb909faed9cad..4eca3baad324aaaaac91e1b2ecc43bca5c23da4a 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/ctor_result_type.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/ctor_result_type.pass.cpp
@@ -237,8 +237,10 @@ test2()
     assert(os.str() == a);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/ctor_sseq.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/ctor_sseq.pass.cpp
index d695441cd68b26619f374414fa82f87d095b5f8f..b46029a2923922d3f8530dacbbd3b0171518d40d 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/ctor_sseq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/ctor_sseq.pass.cpp
@@ -301,8 +301,10 @@ test2()
     assert(os.str() == a);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/ctor_sseq_all_zero.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/ctor_sseq_all_zero.pass.cpp
index 9f298ea4995bce98566da3b23d15fda4b3baf44b..a2489cf63660a4ff29f5b8674e2d135a532eb0c8 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/ctor_sseq_all_zero.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/ctor_sseq_all_zero.pass.cpp
@@ -71,10 +71,12 @@ void test(void) {
   assert(e() == X0);
 }
 
-int main() {
+int main(int, char**) {
   // Test for k == 1: word_size <= 32.
   test<unsigned short, 3u>();
 
   // Test for k == 2: (32 < word_size <= 64).
   test<unsigned long long, 33u>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/default.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/default.pass.cpp
index 2d91db790da0800a72f7e5ff0d37a8e016d5aff2..35364f312a932bc9468f0b4a2f2a0afbab7e11e0 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/default.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/default.pass.cpp
@@ -37,8 +37,10 @@ test2()
     assert(e1() == 14514284786278117030ull);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/discard.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/discard.pass.cpp
index 58d59975defe49daad8b9259a998ab5d2abb1a37..750afb1e8a11244ceb77ca1caa248dfcf5c3b177 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/discard.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/discard.pass.cpp
@@ -47,8 +47,10 @@ test2()
     assert(e1 == e2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/eval.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/eval.pass.cpp
index 9d44192f3f3884c8e9ae4664228f4db0dd16be93..03e87dad8c45fb11f6d5c39bb8f8527bf111064c 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/eval.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/eval.pass.cpp
@@ -37,8 +37,10 @@ test2()
     assert(e() == 13109570281517897720ull);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/io.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/io.pass.cpp
index 8f7c699ee6510cb6273063d2c48a601c341bb5bc..cbc764e8dd6eb4d8e99838b1cb069aa8c739db0c 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/io.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/io.pass.cpp
@@ -61,8 +61,10 @@ test2()
     assert(e1 == e2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/result_type.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/result_type.pass.cpp
index ce0506043c989b3773736f42d38034c6ba8491b8..7987d65748e74e04b2320c13fee4f8ea68496763 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/result_type.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/result_type.pass.cpp
@@ -36,8 +36,10 @@ test2()
         std::uint_fast64_t>::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/seed_result_type.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/seed_result_type.pass.cpp
index ef529ffcf6b243a881533e7ebb885309559145e3..ff7d07374cbf16ab2926e1bf03986f6e1e86a55d 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/seed_result_type.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/seed_result_type.pass.cpp
@@ -44,8 +44,10 @@ test2()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/seed_sseq.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/seed_sseq.pass.cpp
index 3d05ce779cf0efe2bb34cd139728f0034a434a0d..8ad2ec289f6851180e27cbdf1dbf41b4a60ab213 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/seed_sseq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/seed_sseq.pass.cpp
@@ -42,8 +42,10 @@ test2()
     assert(e1 == e2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/values.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/values.pass.cpp
index 62ac9f516a87c09c0869cce58e03b4ef5c45fda6..1af1d85b25fe4301e53a1b591346fa164c956a9d 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/values.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.mers/values.pass.cpp
@@ -126,8 +126,10 @@ test2()
     where(E::default_seed);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/assign.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/assign.pass.cpp
index c05831165f8b9954c94a0ee260fa5a41357a0236..e6cce1b2da70f3b4f130f72ead1e6fef85bcc001 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/assign.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/assign.pass.cpp
@@ -48,8 +48,10 @@ test2()
     assert(e1 == e2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/copy.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/copy.pass.cpp
index 70a2b5b2cf778037d00bd0f3b6deb141617e18f6..c39f39858e4175d1694f976188e026a5639b8a72 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/copy.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/copy.pass.cpp
@@ -46,8 +46,10 @@ test2()
     assert(e1 == e2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/ctor_result_type.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/ctor_result_type.pass.cpp
index 3045b06c92f36687b9f7fa4cdf751698cb54c1ca..5a178e82e6f4179c2b24935a2ef23cec89071493 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/ctor_result_type.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/ctor_result_type.pass.cpp
@@ -43,8 +43,10 @@ test2()
     assert(os.str() == a);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/ctor_sseq.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/ctor_sseq.pass.cpp
index 361a0fc25dd3341af48bc3b7f2c36caf7b42a6c7..0ed496e71af0cf4bf3fa3a35b22dcd4eba4652c8 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/ctor_sseq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/ctor_sseq.pass.cpp
@@ -47,8 +47,10 @@ test2()
     assert(os.str() == a);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/default.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/default.pass.cpp
index 13dede1aa949f6ef45d5923fd1c7a040b751cc22..dbc4c5b4cb82c6406815a5224414bbc40fb9d723 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/default.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/default.pass.cpp
@@ -34,8 +34,10 @@ test2()
     assert(e1() == 23459059301164ull);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/discard.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/discard.pass.cpp
index f4824cd9a1ca7bdfda1d6f046290da8c58e4bcbb..4d039289bffbb29bcdfeca105c8ce53a870391d7 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/discard.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/discard.pass.cpp
@@ -44,8 +44,10 @@ test2()
     assert(e1 == e2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/eval.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/eval.pass.cpp
index 818d66c441e58fb98a87b77a047e481ff4a3869c..d8d03c09ee5a9a64b49e8db3d30b692461b52ee9 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/eval.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/eval.pass.cpp
@@ -34,8 +34,10 @@ test2()
     assert(e() == 276846226770426ull);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/io.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/io.pass.cpp
index 88d0910d2e7192d3a6571489d58178edf11e2a1d..d3eeda3be4a8f4a9ffb081defff08f952f93b8f5 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/io.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/io.pass.cpp
@@ -55,8 +55,10 @@ test2()
     assert(e1 == e2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/result_type.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/result_type.pass.cpp
index cc0fa903adc49b7a0319a5f65d642b3cb9902638..5312bb1ff3affc201fa61ec694f158465e0515e7 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/result_type.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/result_type.pass.cpp
@@ -34,8 +34,10 @@ test2()
         std::uint_fast64_t>::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/seed_result_type.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/seed_result_type.pass.cpp
index 201ec38d1e594375eebe764fdb6647d26c2490a3..637841a679bfd3bcb016fef45a67f98ab8b34fc8 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/seed_result_type.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/seed_result_type.pass.cpp
@@ -42,8 +42,10 @@ test2()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/seed_sseq.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/seed_sseq.pass.cpp
index 2a178388ce075b52c74d316471b4de555da469d5..85199c0ef3b85310984b0d116522e8f8c5120399 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/seed_sseq.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/seed_sseq.pass.cpp
@@ -40,8 +40,10 @@ test2()
     assert(e1 == e2);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/values.pass.cpp b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/values.pass.cpp
index 758a5957f120a691b5ecc22d3c5cee0064575615..a877eff1383be34bd11335a01d38e04cfc34c391 100644
--- a/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/values.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.eng/rand.eng.sub/values.pass.cpp
@@ -74,8 +74,10 @@ test2()
     where(E::default_seed);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.predef/default_random_engine.pass.cpp b/libcxx/test/std/numerics/rand/rand.predef/default_random_engine.pass.cpp
index a5b9334c61766fd3903edcc9d7113bbc1aa4cb8f..b06cd4656610d313bd36b68986e5cb2951a305e2 100644
--- a/libcxx/test/std/numerics/rand/rand.predef/default_random_engine.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.predef/default_random_engine.pass.cpp
@@ -15,9 +15,11 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     std::default_random_engine e;
     e.discard(9999);
     LIBCPP_ASSERT(e() == 399268537u);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.predef/knuth_b.pass.cpp b/libcxx/test/std/numerics/rand/rand.predef/knuth_b.pass.cpp
index a06bbe966efe8e052c04531d0112cfbea97f0115..d81f788e5e052f0cb55b34b77063e2b319d16939 100644
--- a/libcxx/test/std/numerics/rand/rand.predef/knuth_b.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.predef/knuth_b.pass.cpp
@@ -13,9 +13,11 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::knuth_b e;
     e.discard(9999);
     assert(e() == 1112339016u);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.predef/minstd_rand.pass.cpp b/libcxx/test/std/numerics/rand/rand.predef/minstd_rand.pass.cpp
index 9a44b4c0ab005b14d79a25fa3cc1bf45a4740538..d38b009e5f8b18b996e7417994513318bbcb49f9 100644
--- a/libcxx/test/std/numerics/rand/rand.predef/minstd_rand.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.predef/minstd_rand.pass.cpp
@@ -14,9 +14,11 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::minstd_rand e;
     e.discard(9999);
     assert(e() == 399268537u);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.predef/minstd_rand0.pass.cpp b/libcxx/test/std/numerics/rand/rand.predef/minstd_rand0.pass.cpp
index f676f5f00e9ff08f82f9a8f48aa12e32a441a8a8..4e4f07eae781c8ff906d3f8da2751b447b57a48a 100644
--- a/libcxx/test/std/numerics/rand/rand.predef/minstd_rand0.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.predef/minstd_rand0.pass.cpp
@@ -14,9 +14,11 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::minstd_rand0 e;
     e.discard(9999);
     assert(e() == 1043618065u);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.predef/mt19937.pass.cpp b/libcxx/test/std/numerics/rand/rand.predef/mt19937.pass.cpp
index 2816661632531c83d2b46d50b9a0d5da09933a21..16390964f58a659aaa23c200294ffc4d6148995a 100644
--- a/libcxx/test/std/numerics/rand/rand.predef/mt19937.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.predef/mt19937.pass.cpp
@@ -18,9 +18,11 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::mt19937 e;
     e.discard(9999);
     assert(e() == 4123659995u);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.predef/mt19937_64.pass.cpp b/libcxx/test/std/numerics/rand/rand.predef/mt19937_64.pass.cpp
index 80ffb429e54da1ffcc8857459213aa55c60f3e8f..c6a3b4ebdf91dcb3b72029ed203ffc1d190a8060 100644
--- a/libcxx/test/std/numerics/rand/rand.predef/mt19937_64.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.predef/mt19937_64.pass.cpp
@@ -18,9 +18,11 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::mt19937_64 e;
     e.discard(9999);
     assert(e() == 9981545732273789042ull);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.predef/ranlux24.pass.cpp b/libcxx/test/std/numerics/rand/rand.predef/ranlux24.pass.cpp
index c58f09dcc806ef6fddf77fc7d22030626b7790c9..9805d1add87dba9ad6acd80dfa75d8591957a639 100644
--- a/libcxx/test/std/numerics/rand/rand.predef/ranlux24.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.predef/ranlux24.pass.cpp
@@ -13,9 +13,11 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::ranlux24 e;
     e.discard(9999);
     assert(e() == 9901578u);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.predef/ranlux24_base.pass.cpp b/libcxx/test/std/numerics/rand/rand.predef/ranlux24_base.pass.cpp
index 30d94e696637e2ed489c84e1bd46e8256233ef26..21c68699bfaeef2c34b7087f8f76b2eea845c825 100644
--- a/libcxx/test/std/numerics/rand/rand.predef/ranlux24_base.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.predef/ranlux24_base.pass.cpp
@@ -13,9 +13,11 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::ranlux24_base e;
     e.discard(9999);
     assert(e() == 7937952u);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.predef/ranlux48.pass.cpp b/libcxx/test/std/numerics/rand/rand.predef/ranlux48.pass.cpp
index 22c45db40b18292e39e3de425fadb18b7e848fee..2ab37e1c72885a3c33d2bbcef5007c233bd441b5 100644
--- a/libcxx/test/std/numerics/rand/rand.predef/ranlux48.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.predef/ranlux48.pass.cpp
@@ -13,9 +13,11 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::ranlux48 e;
     e.discard(9999);
     assert(e() == 249142670248501ull);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.predef/ranlux48_base.pass.cpp b/libcxx/test/std/numerics/rand/rand.predef/ranlux48_base.pass.cpp
index 8faefbb4cc231d1b26779111573c59df072afc6a..93bb14c5c939d2641a6e3df8b78c90b18944fb93 100644
--- a/libcxx/test/std/numerics/rand/rand.predef/ranlux48_base.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.predef/ranlux48_base.pass.cpp
@@ -13,9 +13,11 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::ranlux48_base e;
     e.discard(9999);
     assert(e() == 61839128582725ull);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.req/nothing_to_do.pass.cpp b/libcxx/test/std/numerics/rand/rand.req/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/numerics/rand/rand.req/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.req/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.req/rand.req.adapt/nothing_to_do.pass.cpp b/libcxx/test/std/numerics/rand/rand.req/rand.req.adapt/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/numerics/rand/rand.req/rand.req.adapt/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.req/rand.req.adapt/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.req/rand.req.dst/nothing_to_do.pass.cpp b/libcxx/test/std/numerics/rand/rand.req/rand.req.dst/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/numerics/rand/rand.req/rand.req.dst/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.req/rand.req.dst/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.req/rand.req.eng/nothing_to_do.pass.cpp b/libcxx/test/std/numerics/rand/rand.req/rand.req.eng/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/numerics/rand/rand.req/rand.req.eng/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.req/rand.req.eng/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.req/rand.req.genl/nothing_to_do.pass.cpp b/libcxx/test/std/numerics/rand/rand.req/rand.req.genl/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/numerics/rand/rand.req/rand.req.genl/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.req/rand.req.genl/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.req/rand.req.seedseq/nothing_to_do.pass.cpp b/libcxx/test/std/numerics/rand/rand.req/rand.req.seedseq/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/numerics/rand/rand.req/rand.req.seedseq/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.req/rand.req.seedseq/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.req/rand.req.urng/nothing_to_do.pass.cpp b/libcxx/test/std/numerics/rand/rand.req/rand.req.urng/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/numerics/rand/rand.req/rand.req.urng/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.req/rand.req.urng/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.util/nothing_to_do.pass.cpp b/libcxx/test/std/numerics/rand/rand.util/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/numerics/rand/rand.util/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.util/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.util/rand.util.canonical/generate_canonical.pass.cpp b/libcxx/test/std/numerics/rand/rand.util/rand.util.canonical/generate_canonical.pass.cpp
index 62e129b989f43b6a1b1c834b8fe35691f1a8facf..a05c0846af70bb89dfa9ce4323ef687e6f1047cc 100644
--- a/libcxx/test/std/numerics/rand/rand.util/rand.util.canonical/generate_canonical.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.util/rand.util.canonical/generate_canonical.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "truncate_fp.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::minstd_rand0 E;
@@ -98,4 +98,6 @@ int main()
             (282475249 - E::min()) * (E::max() - E::min() + F(1))) /
             ((E::max() - E::min() + F(1)) * (E::max() - E::min() + F(1)))));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.util/rand.util.seedseq/assign.fail.cpp b/libcxx/test/std/numerics/rand/rand.util/rand.util.seedseq/assign.fail.cpp
index f9a5bc05ecd7dc0cb0dcbf16554dbffa9ff3c6f4..de06a5e9b57d70bd11cfefc23fbe8fd21ad5eefa 100644
--- a/libcxx/test/std/numerics/rand/rand.util/rand.util.seedseq/assign.fail.cpp
+++ b/libcxx/test/std/numerics/rand/rand.util/rand.util.seedseq/assign.fail.cpp
@@ -14,9 +14,11 @@
 
 #include <random>
 
-int main()
+int main(int, char**)
 {
     std::seed_seq s0;
     std::seed_seq s;
     s = s0;
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.util/rand.util.seedseq/copy.fail.cpp b/libcxx/test/std/numerics/rand/rand.util/rand.util.seedseq/copy.fail.cpp
index 5e6ed7a01d4e97f71ed0f761f71d61c5b5f98ffb..7c3c38ea7a1dd94b0b831833d90ef8bef8ca251a 100644
--- a/libcxx/test/std/numerics/rand/rand.util/rand.util.seedseq/copy.fail.cpp
+++ b/libcxx/test/std/numerics/rand/rand.util/rand.util.seedseq/copy.fail.cpp
@@ -14,8 +14,10 @@
 
 #include <random>
 
-int main()
+int main(int, char**)
 {
     std::seed_seq s0;
     std::seed_seq s(s0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.util/rand.util.seedseq/default.pass.cpp b/libcxx/test/std/numerics/rand/rand.util/rand.util.seedseq/default.pass.cpp
index 1002ea8a440b67dacb49b1cf601853c29b645a23..87608e63c04dc6f18d536c9589c857e092aed372 100644
--- a/libcxx/test/std/numerics/rand/rand.util/rand.util.seedseq/default.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.util/rand.util.seedseq/default.pass.cpp
@@ -15,8 +15,10 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::seed_seq s;
     assert(s.size() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.util/rand.util.seedseq/generate.pass.cpp b/libcxx/test/std/numerics/rand/rand.util/rand.util.seedseq/generate.pass.cpp
index db32abddc6fcf22680a9dd5e9a3954301e3ff55d..e328777782b8b2198bc3cfe1215d9a598019fa94 100644
--- a/libcxx/test/std/numerics/rand/rand.util/rand.util.seedseq/generate.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.util/rand.util.seedseq/generate.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         // These numbers generated from a slightly altered version of dSFMT
@@ -801,4 +801,6 @@ int main()
         for (int i = 0; i < n; ++i)
             assert(a[i] == b[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.util/rand.util.seedseq/initializer_list.pass.cpp b/libcxx/test/std/numerics/rand/rand.util/rand.util.seedseq/initializer_list.pass.cpp
index 2d1656a3c03c3ce211d95fd4e103630d9c1e6ef1..656981b1a93033e2fec6d1ed1f3bc523846dcef1 100644
--- a/libcxx/test/std/numerics/rand/rand.util/rand.util.seedseq/initializer_list.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.util/rand.util.seedseq/initializer_list.pass.cpp
@@ -18,7 +18,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::seed_seq s= {5, 4, 3, 2, 1};
     assert(s.size() == 5);
@@ -29,4 +29,6 @@ int main()
     assert(b[2] == 3);
     assert(b[3] == 2);
     assert(b[4] == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.util/rand.util.seedseq/iterator.pass.cpp b/libcxx/test/std/numerics/rand/rand.util/rand.util.seedseq/iterator.pass.cpp
index 3b1a79ec395184b0961d2d82f9a8123ec556f9da..10f7b34727e375642c9adac70301e7c44d9ad443 100644
--- a/libcxx/test/std/numerics/rand/rand.util/rand.util.seedseq/iterator.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.util/rand.util.seedseq/iterator.pass.cpp
@@ -16,7 +16,7 @@
 #include <random>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     unsigned a[5] = {5, 4, 3, 2, 1};
     std::seed_seq s(a, a+5);
@@ -28,4 +28,6 @@ int main()
     assert(b[2] == 3);
     assert(b[3] == 2);
     assert(b[4] == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/numerics/rand/rand.util/rand.util.seedseq/types.pass.cpp b/libcxx/test/std/numerics/rand/rand.util/rand.util.seedseq/types.pass.cpp
index d169811db29852a6daea551f33f61bc6f2ba6b6e..50cfa7d59ccd91b409f328ac9fc1f19f713133df 100644
--- a/libcxx/test/std/numerics/rand/rand.util/rand.util.seedseq/types.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.util/rand.util.seedseq/types.pass.cpp
@@ -17,7 +17,9 @@
 #include <random>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::seed_seq::result_type, std::uint_least32_t>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/nothing_to_do.pass.cpp b/libcxx/test/std/re/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/re/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/re/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/nothing_to_do.pass.cpp b/libcxx/test/std/re/re.alg/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/re/re.alg/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/re/re.alg/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/re.alg.match/awk.pass.cpp b/libcxx/test/std/re/re.alg/re.alg.match/awk.pass.cpp
index 095980c605535aa2fe598b60b60fb924ac62108d..43fc9b89cb8502625c854baa00122047e85dd236 100644
--- a/libcxx/test/std/re/re.alg/re.alg.match/awk.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.match/awk.pass.cpp
@@ -27,7 +27,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::cmatch m;
@@ -1391,4 +1391,5 @@ int main()
         assert(m.position(0) == 0);
         assert(m.str(0) == s);
     }
+    return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/re.alg.match/basic.fail.cpp b/libcxx/test/std/re/re.alg/re.alg.match/basic.fail.cpp
index bc5e4b75d9392dbff3d9310cc1a95dfb95d2caed..d71fc280a29f25729f169a59e820a2625f7cf249 100644
--- a/libcxx/test/std/re/re.alg/re.alg.match/basic.fail.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.match/basic.fail.cpp
@@ -25,11 +25,13 @@
 #error
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         std::smatch m;
         std::regex re{"*"};
         std::regex_match(std::string("abcde"), m, re);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/re.alg.match/basic.pass.cpp b/libcxx/test/std/re/re.alg/re.alg.match/basic.pass.cpp
index d6a0b0da71da8ddb8580f5588f4c4d0c9620f9af..b2fa6e941356d15f198c51c8e4491ad28d359389 100644
--- a/libcxx/test/std/re/re.alg/re.alg.match/basic.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.match/basic.pass.cpp
@@ -30,7 +30,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::cmatch m;
@@ -1367,4 +1367,6 @@ int main()
         assert(m.position(0) == 0);
         assert(m.str(0) == s);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/re.alg.match/ecma.pass.cpp b/libcxx/test/std/re/re.alg/re.alg.match/ecma.pass.cpp
index c1e910c77aa2e0f18dba8e1b5cb98c437029de1d..e15533da6f317a684ad15f8afcb76a03fd8717dc 100644
--- a/libcxx/test/std/re/re.alg/re.alg.match/ecma.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.match/ecma.pass.cpp
@@ -30,7 +30,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::cmatch m;
@@ -1391,4 +1391,6 @@ int main()
         assert(m.position(0) == 0);
         assert(m.str(0) == s);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/re.alg.match/egrep.pass.cpp b/libcxx/test/std/re/re.alg/re.alg.match/egrep.pass.cpp
index 8789e7d73706c6a45d2d6d75dac093ad6ea8ca0d..4e1b6940c09e172be070c422383818ce3cb9da87 100644
--- a/libcxx/test/std/re/re.alg/re.alg.match/egrep.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.match/egrep.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_macros.h"
 #include "test_iterators.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::cmatch m;
@@ -78,4 +78,6 @@ int main()
         assert(m.position(0) == 0);
         assert(m.str(0) == "tourna");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/re.alg.match/exponential.pass.cpp b/libcxx/test/std/re/re.alg/re.alg.match/exponential.pass.cpp
index f23bef36ec1d7451fdca1be94195760e4dd01ec2..a1ba80f26811010d8a6c84c7d4f2bc7a437c96d4 100644
--- a/libcxx/test/std/re/re.alg/re.alg.match/exponential.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.match/exponential.pass.cpp
@@ -23,7 +23,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main() {
+int main(int, char**) {
   for (std::regex_constants::syntax_option_type op :
        {std::regex::ECMAScript, std::regex::extended, std::regex::egrep,
         std::regex::awk}) {
diff --git a/libcxx/test/std/re/re.alg/re.alg.match/extended.pass.cpp b/libcxx/test/std/re/re.alg/re.alg.match/extended.pass.cpp
index b04d750a3f3ad82bc5d46fad0807c0d8e12c2dcc..9415505faaf82325d24a3973a4cdb2514b71694e 100644
--- a/libcxx/test/std/re/re.alg/re.alg.match/extended.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.match/extended.pass.cpp
@@ -30,7 +30,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::cmatch m;
@@ -1363,4 +1363,6 @@ int main()
         assert(m.position(0) == 0);
         assert(m.str(0) == s);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/re.alg.match/grep.pass.cpp b/libcxx/test/std/re/re.alg/re.alg.match/grep.pass.cpp
index 0c68dca69835de559f790831770d2650b6ff16e1..0f75d618c0c0224e9cec9fdb77449fe7da71d600 100644
--- a/libcxx/test/std/re/re.alg/re.alg.match/grep.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.match/grep.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_macros.h"
 #include "test_iterators.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::cmatch m;
@@ -46,4 +46,6 @@ int main()
                 std::regex_constants::grep)));
         assert(m.size() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/re.alg.match/inverted_character_classes.pass.cpp b/libcxx/test/std/re/re.alg/re.alg.match/inverted_character_classes.pass.cpp
index 67bfd96f4dd8db6f766266be6b4202290e3c521a..d48d86ee64cf2d67bdf9f2e1a9e033ee94e9262e 100644
--- a/libcxx/test/std/re/re.alg/re.alg.match/inverted_character_classes.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.match/inverted_character_classes.pass.cpp
@@ -15,7 +15,7 @@
 #include <regex>
 
 
-int main() {
+int main(int, char**) {
     assert(std::regex_match("X", std::regex("[X]")));
     assert(std::regex_match("X", std::regex("[XY]")));
     assert(!std::regex_match("X", std::regex("[^X]")));
@@ -40,4 +40,6 @@ int main() {
     assert(!std::regex_match("_", std::regex("[\\W]")));
     assert(std::regex_match("X", std::regex("[^\\W]")));
     assert(std::regex_match("_", std::regex("[^\\W]")));
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/re.alg.match/lookahead_capture.pass.cpp b/libcxx/test/std/re/re.alg/re.alg.match/lookahead_capture.pass.cpp
index ec8467f4e63c49ca06fa1c2d652e7320574b812e..1550f3728563a8fc514012ff35cf14de703a9ae5 100644
--- a/libcxx/test/std/re/re.alg/re.alg.match/lookahead_capture.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.match/lookahead_capture.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_macros.h"
 #include "test_iterators.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::regex re("^(?=(.))a$");
@@ -95,4 +95,6 @@ int main()
         assert(m[3] == "a");
         assert(m[4] == "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/re.alg.match/parse_curly_brackets.pass.cpp b/libcxx/test/std/re/re.alg/re.alg.match/parse_curly_brackets.pass.cpp
index b6d3e1ae334ee958713e627c3d0a70b8c6747f8a..291798cfcc9a974ca8d5f868f8d3d891d5fd0b96 100644
--- a/libcxx/test/std/re/re.alg/re.alg.match/parse_curly_brackets.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.match/parse_curly_brackets.pass.cpp
@@ -62,10 +62,12 @@ test4()
     assert((std::regex_match(target, smatch, regex)));
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
     test3();
     test4();
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/re.alg.replace/exponential.pass.cpp b/libcxx/test/std/re/re.alg/re.alg.replace/exponential.pass.cpp
index 715aa0affe47bad3759d379ee1ee15e9184db84d..868c3d8350b375278cfa39c17cb1c622738186fa 100644
--- a/libcxx/test/std/re/re.alg/re.alg.replace/exponential.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.replace/exponential.pass.cpp
@@ -24,7 +24,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     try {
         std::regex re("a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?aaaaaaaaaaaaaaaaaaaa");
@@ -35,4 +35,5 @@ int main()
     } catch (const std::regex_error &e) {
       assert(e.code() == std::regex_constants::error_complexity);
     }
+    return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/re.alg.replace/test1.pass.cpp b/libcxx/test/std/re/re.alg/re.alg.replace/test1.pass.cpp
index df68aae9381fc0fe535206d8e90af2d1a2bb87b7..7e5332aaff872e30c955e307ae52735fb0da25d3 100644
--- a/libcxx/test/std/re/re.alg/re.alg.replace/test1.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.replace/test1.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_macros.h"
 #include "test_iterators.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::regex phone_numbers("\\d{3}-\\d{4}");
@@ -104,4 +104,6 @@ int main()
         assert(r.base() == buf+12);
         assert(buf == std::string("123-555-1234"));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/re.alg.replace/test2.pass.cpp b/libcxx/test/std/re/re.alg/re.alg.replace/test2.pass.cpp
index 1cfaec6797e3df4defb0b5a7daa575447edc7523..d5e3b64a3ebe980d69ca4d0621da6324e61ff746 100644
--- a/libcxx/test/std/re/re.alg/re.alg.replace/test2.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.replace/test2.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_macros.h"
 #include "test_iterators.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::regex phone_numbers("\\d{3}-\\d{4}");
@@ -104,4 +104,6 @@ int main()
         assert(r.base() == buf+12);
         assert(buf == std::string("123-555-1234"));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/re.alg.replace/test3.pass.cpp b/libcxx/test/std/re/re.alg/re.alg.replace/test3.pass.cpp
index ebfb20d7bd57ff50ef086028fd0ff0974482225d..09ecc53a9f998d4346806dbdd21384bca2ea3e00 100644
--- a/libcxx/test/std/re/re.alg/re.alg.replace/test3.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.replace/test3.pass.cpp
@@ -20,7 +20,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::regex phone_numbers("\\d{3}-\\d{4}");
@@ -70,4 +70,6 @@ int main()
                                            std::regex_constants::format_no_copy);
         assert(r == "123-555-1234");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/re.alg.replace/test4.pass.cpp b/libcxx/test/std/re/re.alg/re.alg.replace/test4.pass.cpp
index 88816e3d7ac22ea1b0fde7b601ec99bee3efe49d..4d567ed1f644f531d1000ac0e7159d08826a9f90 100644
--- a/libcxx/test/std/re/re.alg/re.alg.replace/test4.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.replace/test4.pass.cpp
@@ -19,7 +19,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::regex phone_numbers("\\d{3}-\\d{4}");
@@ -69,4 +69,6 @@ int main()
                                            std::regex_constants::format_no_copy);
         assert(r == "123-555-1234");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/re.alg.replace/test5.pass.cpp b/libcxx/test/std/re/re.alg/re.alg.replace/test5.pass.cpp
index bcff51eddd131a1c5dd4f2688adf80421da34fec..585a60f8780e1903a47b031213f0d6779267650f 100644
--- a/libcxx/test/std/re/re.alg/re.alg.replace/test5.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.replace/test5.pass.cpp
@@ -20,7 +20,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::regex phone_numbers("\\d{3}-\\d{4}");
@@ -70,4 +70,6 @@ int main()
                                            std::regex_constants::format_no_copy);
         assert(r == "123-555-1234");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/re.alg.replace/test6.pass.cpp b/libcxx/test/std/re/re.alg/re.alg.replace/test6.pass.cpp
index 923230aea4b9f62229b041e14b5f66a9300661a0..66a910172c4972c21a25de508845fa8e51932814 100644
--- a/libcxx/test/std/re/re.alg/re.alg.replace/test6.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.replace/test6.pass.cpp
@@ -20,7 +20,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::regex phone_numbers("\\d{3}-\\d{4}");
@@ -70,4 +70,6 @@ int main()
                                            std::regex_constants::format_no_copy);
         assert(r == "123-555-1234");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/re.alg.search/awk.pass.cpp b/libcxx/test/std/re/re.alg/re.alg.search/awk.pass.cpp
index 13f9646f42b906d5d8133ec44946226cedcf8b0c..0f8fb14f586f4805fdbb34f859d7b91ac0dbf5c8 100644
--- a/libcxx/test/std/re/re.alg/re.alg.search/awk.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.search/awk.pass.cpp
@@ -30,7 +30,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::cmatch m;
@@ -1574,4 +1574,6 @@ int main()
         assert(m.position(0) == 0);
         assert(m.str(0) == s);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/re.alg.search/backup.pass.cpp b/libcxx/test/std/re/re.alg/re.alg.search/backup.pass.cpp
index 710cf226c971fbb76f547546f2914163b93e71c0..d27124a8d8039f84301e0b2e96e69aa291c2c219 100644
--- a/libcxx/test/std/re/re.alg/re.alg.search/backup.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.search/backup.pass.cpp
@@ -21,7 +21,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     // This regex_iterator uses regex_search(__wrap_iter<_Iter> __first, ...)
     // Test for https://bugs.llvm.org/show_bug.cgi?id=16240 fixed in r185273.
@@ -60,4 +60,6 @@ int main()
         ++it;
         assert(it == end);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/re.alg.search/basic.fail.cpp b/libcxx/test/std/re/re.alg/re.alg.search/basic.fail.cpp
index d84b1c97bdc7c3e466b101e6c71a85a60a7d4c62..fb9677f7e93927e89ee3cd5f664c8481dcc2cac1 100644
--- a/libcxx/test/std/re/re.alg/re.alg.search/basic.fail.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.search/basic.fail.cpp
@@ -25,11 +25,13 @@
 #error
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         std::smatch m;
         std::regex re{"*"};
         std::regex_search(std::string("abcde"), m, re);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/re.alg.search/basic.pass.cpp b/libcxx/test/std/re/re.alg/re.alg.search/basic.pass.cpp
index ee919b223b64bc0cc8ba384d575545aa0278ce95..bd96c9830c0800eba057a25e086b839f3604f1d6 100644
--- a/libcxx/test/std/re/re.alg/re.alg.search/basic.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.search/basic.pass.cpp
@@ -30,7 +30,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::cmatch m;
@@ -1547,4 +1547,6 @@ int main()
         assert(m.position(0) == 0);
         assert(m.str(0) == s);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/re.alg.search/ecma.pass.cpp b/libcxx/test/std/re/re.alg/re.alg.search/ecma.pass.cpp
index afc5a005b6aa59478a56c6eef80e56dde15a75c2..7e74caa0808aa8f078f7c6d38f281fab1db783da 100644
--- a/libcxx/test/std/re/re.alg/re.alg.search/ecma.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.search/ecma.pass.cpp
@@ -30,7 +30,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::cmatch m;
@@ -1589,4 +1589,6 @@ int main()
         assert(m.position(0) == 0);
         assert(m.str(0) == s);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/re.alg.search/egrep.pass.cpp b/libcxx/test/std/re/re.alg/re.alg.search/egrep.pass.cpp
index 4e32952608805682aa195826899899d91ad39e1d..df8560f5fa8c4f767f53bef79afaaea6af075a21 100644
--- a/libcxx/test/std/re/re.alg/re.alg.search/egrep.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.search/egrep.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_macros.h"
 #include "test_iterators.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::cmatch m;
@@ -87,4 +87,6 @@ int main()
         assert(m.position(0) == 0);
         assert(m.str(0) == "tourna");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/re.alg.search/exponential.pass.cpp b/libcxx/test/std/re/re.alg/re.alg.search/exponential.pass.cpp
index 6de3bbffd6726326bdcebc4066580b1fb010e205..a9eb2b2b94e65dc69b07db64001d7cd74169e029 100644
--- a/libcxx/test/std/re/re.alg/re.alg.search/exponential.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.search/exponential.pass.cpp
@@ -23,7 +23,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main() {
+int main(int, char**) {
   for (std::regex_constants::syntax_option_type op :
        {std::regex::ECMAScript, std::regex::extended, std::regex::egrep,
         std::regex::awk}) {
diff --git a/libcxx/test/std/re/re.alg/re.alg.search/extended.pass.cpp b/libcxx/test/std/re/re.alg/re.alg.search/extended.pass.cpp
index 6c9cabeff24b25a28137a0006507af4f2b5c01db..62e4822dbd17a38f0b99b25e60ec584997533075 100644
--- a/libcxx/test/std/re/re.alg/re.alg.search/extended.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.search/extended.pass.cpp
@@ -30,7 +30,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::cmatch m;
@@ -1543,4 +1543,6 @@ int main()
         assert(m.position(0) == 0);
         assert(m.str(0) == s);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/re.alg.search/grep.pass.cpp b/libcxx/test/std/re/re.alg/re.alg.search/grep.pass.cpp
index 8844b4e6fb95a68830cec1f1a55391c95194c33e..29300a818119b95c52f0b1a5055bf35c936f5338 100644
--- a/libcxx/test/std/re/re.alg/re.alg.search/grep.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.search/grep.pass.cpp
@@ -50,7 +50,7 @@ void fuzz_tests()  // patterns that the fuzzer has found
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::cmatch m;
@@ -85,4 +85,6 @@ int main()
         assert(m.str(0) == "");
     }
     fuzz_tests();
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/re.alg.search/invert_neg_word_search.pass.cpp b/libcxx/test/std/re/re.alg/re.alg.search/invert_neg_word_search.pass.cpp
index 98343f55401d23c280624a6ea9d945d8e3a0e46a..63fd5ae57aec9afe62598cf3e732d88160c0b6aa 100644
--- a/libcxx/test/std/re/re.alg/re.alg.search/invert_neg_word_search.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.search/invert_neg_word_search.pass.cpp
@@ -20,7 +20,7 @@
 
 
 // PR34310
-int main()
+int main(int, char**)
 {
   assert(std::regex_search("HelloWorld", std::regex("[^\\W]")));
   assert(std::regex_search("_", std::regex("[^\\W]")));
diff --git a/libcxx/test/std/re/re.alg/re.alg.search/lookahead.pass.cpp b/libcxx/test/std/re/re.alg/re.alg.search/lookahead.pass.cpp
index b4a47f09b9e678551d4e064c2d0a972cd29dfeab..7846eca2abec4beb1dc4418a1a3016d345d079bf 100644
--- a/libcxx/test/std/re/re.alg/re.alg.search/lookahead.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.search/lookahead.pass.cpp
@@ -21,8 +21,10 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     assert(!std::regex_search("ab", std::regex("(?=^)b")));
     assert(!std::regex_search("ab", std::regex("a(?=^)b")));
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/re.alg.search/no_update_pos.pass.cpp b/libcxx/test/std/re/re.alg/re.alg.search/no_update_pos.pass.cpp
index 8bfcfa007fb1f272c9421de0211acf4b6b0a4ce6..73158dc53c9128b7efc70b32a5d83c414acf0a56 100644
--- a/libcxx/test/std/re/re.alg/re.alg.search/no_update_pos.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.alg.search/no_update_pos.pass.cpp
@@ -19,7 +19,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     // Iterating over /^a/ should yield one instance at the beginning
     // of the text.
@@ -35,4 +35,6 @@ int main()
 
     ++it;
     assert(it == end);
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.alg/re.except/nothing_to_do.pass.cpp b/libcxx/test/std/re/re.alg/re.except/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/re/re.alg/re.except/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/re/re.alg/re.except/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.badexp/regex_error.pass.cpp b/libcxx/test/std/re/re.badexp/regex_error.pass.cpp
index efcc44f6a46a8fab52ca153b573678be1fc3d75d..a3f4476b05d2dedce1ae2b69790159d605a4e668 100644
--- a/libcxx/test/std/re/re.badexp/regex_error.pass.cpp
+++ b/libcxx/test/std/re/re.badexp/regex_error.pass.cpp
@@ -21,7 +21,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::regex_error e(std::regex_constants::error_collate);
@@ -93,4 +93,6 @@ int main()
         assert(e.what() == std::string("There was insufficient memory to determine whether the regular "
                "expression could match the specified character sequence."));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.const/nothing_to_do.pass.cpp b/libcxx/test/std/re/re.const/nothing_to_do.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/std/re/re.const/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/re/re.const/nothing_to_do.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.const/re.err/error_type.pass.cpp b/libcxx/test/std/re/re.const/re.err/error_type.pass.cpp
index 4369e01706addc1f3e87bf439f884121e4aadc70..51979a5113fdb5784f505e76b2ef3bb1876d9eae 100644
--- a/libcxx/test/std/re/re.const/re.err/error_type.pass.cpp
+++ b/libcxx/test/std/re/re.const/re.err/error_type.pass.cpp
@@ -35,7 +35,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     assert(std::regex_constants::error_collate != 0);
     assert(std::regex_constants::error_ctype != 0);
@@ -140,4 +140,6 @@ int main()
     assert(std::regex_constants::error_badrepeat != std::regex_constants::error_stack);
 
     assert(std::regex_constants::error_complexity != std::regex_constants::error_stack);
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.const/re.matchflag/match_flag_type.pass.cpp b/libcxx/test/std/re/re.const/re.matchflag/match_flag_type.pass.cpp
index bed42547bca1b7cbe9bfff84b2c97d075d321e04..812601463c14213021b650560ae3a5c9bc03c0e7 100644
--- a/libcxx/test/std/re/re.const/re.matchflag/match_flag_type.pass.cpp
+++ b/libcxx/test/std/re/re.const/re.matchflag/match_flag_type.pass.cpp
@@ -35,7 +35,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     assert(std::regex_constants::match_default == 0);
     assert(std::regex_constants::match_not_bol != 0);
@@ -125,4 +125,6 @@ int main()
     e1 &= e2;
     e1 |= e2;
     e1 ^= e2;
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.const/re.matchflag/match_not_bol.pass.cpp b/libcxx/test/std/re/re.const/re.matchflag/match_not_bol.pass.cpp
index e32736630420855e59c70aae9bad5acf2871b1a0..82395e2f2d4d56141e1b0c07e867e3acb65da805 100644
--- a/libcxx/test/std/re/re.const/re.matchflag/match_not_bol.pass.cpp
+++ b/libcxx/test/std/re/re.const/re.matchflag/match_not_bol.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::string target = "foo";
@@ -47,4 +47,6 @@ int main()
     assert( std::regex_search(target, re));
     assert( std::regex_search(target, re, std::regex_constants::match_not_bol));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.const/re.matchflag/match_not_eol.pass.cpp b/libcxx/test/std/re/re.const/re.matchflag/match_not_eol.pass.cpp
index 3d238c5d019de2acb87025eff25f0ba394206fb2..8b13c68bcc3e5db1e076eddf716e26df4087e4ca 100644
--- a/libcxx/test/std/re/re.const/re.matchflag/match_not_eol.pass.cpp
+++ b/libcxx/test/std/re/re.const/re.matchflag/match_not_eol.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::string target = "foo";
@@ -47,4 +47,6 @@ int main()
     assert( std::regex_search(target, re));
     assert( std::regex_search(target, re, std::regex_constants::match_not_eol));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.const/re.matchflag/match_not_null.pass.cpp b/libcxx/test/std/re/re.const/re.matchflag/match_not_null.pass.cpp
index d3389e6b653679a981c244af17a4cf4449015ea7..645f79a0d85c995b4f9b630a3b8ff580dc65b052 100644
--- a/libcxx/test/std/re/re.const/re.matchflag/match_not_null.pass.cpp
+++ b/libcxx/test/std/re/re.const/re.matchflag/match_not_null.pass.cpp
@@ -15,7 +15,7 @@
 #include <cassert>
 #include <regex>
 
-int main()
+int main(int, char**)
 {
   // When match_not_null is on, the regex engine should reject empty matches and
   // move on to try other solutions.
diff --git a/libcxx/test/std/re/re.const/re.synopt/syntax_option_type.pass.cpp b/libcxx/test/std/re/re.const/re.synopt/syntax_option_type.pass.cpp
index 7af7e8cf4d14d1026761f37e17f8c200cb55782d..49ce2b5c4827ba8fad1d85add9ca6e63a7aab428 100644
--- a/libcxx/test/std/re/re.const/re.synopt/syntax_option_type.pass.cpp
+++ b/libcxx/test/std/re/re.const/re.synopt/syntax_option_type.pass.cpp
@@ -32,7 +32,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     assert(std::regex_constants::icase != 0);
     assert(std::regex_constants::nosubs != 0);
@@ -111,4 +111,6 @@ int main()
     e1 &= e2;
     e1 |= e2;
     e1 ^= e2;
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.def/defns.regex.collating.element/nothing_to_do.pass.cpp b/libcxx/test/std/re/re.def/defns.regex.collating.element/nothing_to_do.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/std/re/re.def/defns.regex.collating.element/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/re/re.def/defns.regex.collating.element/nothing_to_do.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.def/defns.regex.finite.state.machine/nothing_to_do.pass.cpp b/libcxx/test/std/re/re.def/defns.regex.finite.state.machine/nothing_to_do.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/std/re/re.def/defns.regex.finite.state.machine/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/re/re.def/defns.regex.finite.state.machine/nothing_to_do.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.def/defns.regex.format.specifier/nothing_to_do.pass.cpp b/libcxx/test/std/re/re.def/defns.regex.format.specifier/nothing_to_do.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/std/re/re.def/defns.regex.format.specifier/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/re/re.def/defns.regex.format.specifier/nothing_to_do.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.def/defns.regex.matched/nothing_to_do.pass.cpp b/libcxx/test/std/re/re.def/defns.regex.matched/nothing_to_do.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/std/re/re.def/defns.regex.matched/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/re/re.def/defns.regex.matched/nothing_to_do.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.def/defns.regex.primary.equivalence.class/nothing_to_do.pass.cpp b/libcxx/test/std/re/re.def/defns.regex.primary.equivalence.class/nothing_to_do.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/std/re/re.def/defns.regex.primary.equivalence.class/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/re/re.def/defns.regex.primary.equivalence.class/nothing_to_do.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.def/defns.regex.regular.expression/nothing_to_do.pass.cpp b/libcxx/test/std/re/re.def/defns.regex.regular.expression/nothing_to_do.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/std/re/re.def/defns.regex.regular.expression/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/re/re.def/defns.regex.regular.expression/nothing_to_do.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.def/defns.regex.subexpression/nothing_to_do.pass.cpp b/libcxx/test/std/re/re.def/defns.regex.subexpression/nothing_to_do.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/std/re/re.def/defns.regex.subexpression/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/re/re.def/defns.regex.subexpression/nothing_to_do.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.def/nothing_to_do.pass.cpp b/libcxx/test/std/re/re.def/nothing_to_do.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/std/re/re.def/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/re/re.def/nothing_to_do.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.general/nothing_to_do.pass.cpp b/libcxx/test/std/re/re.general/nothing_to_do.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/std/re/re.general/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/re/re.general/nothing_to_do.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.grammar/excessive_brace_count.pass.cpp b/libcxx/test/std/re/re.grammar/excessive_brace_count.pass.cpp
index 49bd06e5cac1103385d7e6df68abe08e7ecb7ca4..a5f28d2eec0d41d8b39d6d10862076ad91f4c6f0 100644
--- a/libcxx/test/std/re/re.grammar/excessive_brace_count.pass.cpp
+++ b/libcxx/test/std/re/re.grammar/excessive_brace_count.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main() {
+int main(int, char**) {
   for (std::regex_constants::syntax_option_type op :
        {std::regex::basic, std::regex::grep}) {
     try {
diff --git a/libcxx/test/std/re/re.grammar/nothing_to_do.pass.cpp b/libcxx/test/std/re/re.grammar/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/re/re.grammar/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/re/re.grammar/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.iter/nothing_to_do.pass.cpp b/libcxx/test/std/re/re.iter/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/re/re.iter/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/re/re.iter/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.iter/re.regiter/re.regiter.cnstr/cnstr.fail.cpp b/libcxx/test/std/re/re.iter/re.regiter/re.regiter.cnstr/cnstr.fail.cpp
index 17cce2cb4c459ef3cbd1f1562e96a328776ddc05..34d1ce6ed8e6dd02ba23721a9407793948dd3871 100644
--- a/libcxx/test/std/re/re.iter/re.regiter/re.regiter.cnstr/cnstr.fail.cpp
+++ b/libcxx/test/std/re/re.iter/re.regiter/re.regiter.cnstr/cnstr.fail.cpp
@@ -24,7 +24,7 @@
 #error
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         const char phone_book[] = "555-1234, 555-2345, 555-3456";
@@ -32,4 +32,6 @@ int main()
             std::begin(phone_book), std::end(phone_book),
             std::regex("\\d{3}-\\d{4}"));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.iter/re.regiter/re.regiter.cnstr/cnstr.pass.cpp b/libcxx/test/std/re/re.iter/re.regiter/re.regiter.cnstr/cnstr.pass.cpp
index d944806fded522c2aabe1b01baaff9b6d92ea8f3..a6d10597451054a94f05f015ce36ef56b65ab49d 100644
--- a/libcxx/test/std/re/re.iter/re.regiter/re.regiter.cnstr/cnstr.pass.cpp
+++ b/libcxx/test/std/re/re.iter/re.regiter/re.regiter.cnstr/cnstr.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::regex phone_numbers("\\d{3}-\\d{4}");
@@ -41,4 +41,6 @@ int main()
         ++i;
         assert(i == std::cregex_iterator());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.iter/re.regiter/re.regiter.cnstr/default.pass.cpp b/libcxx/test/std/re/re.iter/re.regiter/re.regiter.cnstr/default.pass.cpp
index ca5670bbb47e7d0948d99f91b7a2f65bed3cfee8..75bd9cab5f21fde3fbbc4abe4bacbc68829dfcca 100644
--- a/libcxx/test/std/re/re.iter/re.regiter/re.regiter.cnstr/default.pass.cpp
+++ b/libcxx/test/std/re/re.iter/re.regiter/re.regiter.cnstr/default.pass.cpp
@@ -25,8 +25,10 @@ test()
     assert(i1 == I());
 }
 
-int main()
+int main(int, char**)
 {
     test<char>();
     test<wchar_t>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.iter/re.regiter/re.regiter.comp/tested_elsewhere.pass.cpp b/libcxx/test/std/re/re.iter/re.regiter/re.regiter.comp/tested_elsewhere.pass.cpp
index 55b506be101a99628355c2a0836df24b0ceec950..f7f71bc8b7c5ae26ae7114df9621cca72e72c8fe 100644
--- a/libcxx/test/std/re/re.iter/re.regiter/re.regiter.comp/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/re/re.iter/re.regiter/re.regiter.comp/tested_elsewhere.pass.cpp
@@ -13,6 +13,8 @@
 // bool operator==(const regex_iterator& right) const;
 // bool operator!=(const regex_iterator& right) const;
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.iter/re.regiter/re.regiter.deref/deref.pass.cpp b/libcxx/test/std/re/re.iter/re.regiter/re.regiter.deref/deref.pass.cpp
index 2643cebc76b03472d9be7dfa9e26ebdb1c4db36b..11b12b2eef8c4c41787adcf5df07825417d34728 100644
--- a/libcxx/test/std/re/re.iter/re.regiter/re.regiter.deref/deref.pass.cpp
+++ b/libcxx/test/std/re/re.iter/re.regiter/re.regiter.deref/deref.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::regex phone_numbers("\\d{3}-\\d{4}");
@@ -39,4 +39,6 @@ int main()
         ++i;
         assert(i == std::cregex_iterator());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.iter/re.regiter/re.regiter.incr/post.pass.cpp b/libcxx/test/std/re/re.iter/re.regiter/re.regiter.incr/post.pass.cpp
index be4126e3e33f54263c7dba72c4a90d242a3a8fd6..ad65f7c13b49557b337f68ffa56644d5f928b75c 100644
--- a/libcxx/test/std/re/re.iter/re.regiter/re.regiter.incr/post.pass.cpp
+++ b/libcxx/test/std/re/re.iter/re.regiter/re.regiter.incr/post.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::regex phone_numbers("\\d{3}-\\d{4}");
@@ -112,4 +112,6 @@ int main()
         ++i;
         assert(i == e);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.iter/re.regiter/types.pass.cpp b/libcxx/test/std/re/re.iter/re.regiter/types.pass.cpp
index 07c3fa64bc7586bf6800b50ea35bcc096f4be162..b96fec78a3c0574cefd08f13c2893a6aae7dc8a8 100644
--- a/libcxx/test/std/re/re.iter/re.regiter/types.pass.cpp
+++ b/libcxx/test/std/re/re.iter/re.regiter/types.pass.cpp
@@ -38,8 +38,10 @@ test()
     static_assert((std::is_same<typename I::iterator_category, std::forward_iterator_tag>::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     test<char>();
     test<wchar_t>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/array.fail.cpp b/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/array.fail.cpp
index bddf58210c5aeb13a84cab77c8d58381e07f762e..a03fd52c03562a3aa078d17cda7d3bda4df25ac5 100644
--- a/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/array.fail.cpp
+++ b/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/array.fail.cpp
@@ -26,7 +26,7 @@
 #error
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         std::regex phone_numbers("\\d{3}-(\\d{4})");
@@ -35,4 +35,6 @@ int main()
         std::cregex_token_iterator i(std::begin(phone_book), std::end(phone_book)-1,
                                      std::regex("\\d{3}-\\d{4}"), indices);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/array.pass.cpp b/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/array.pass.cpp
index eadfbdb44d4955bcafc1c5d6562d92741ab08551..254909a92e03d2692dfb49a456c0036b844a86b9 100644
--- a/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/array.pass.cpp
+++ b/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/array.pass.cpp
@@ -21,7 +21,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::regex phone_numbers("\\d{3}-(\\d{4})");
@@ -61,4 +61,6 @@ int main()
         ++i;
         assert(i == std::cregex_token_iterator());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/default.pass.cpp b/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/default.pass.cpp
index cdbf1a5917dd11fc8bef295df23025cd3f4c19b3..bb70095f139f361fbb5672cb2fa0172251f5ea62 100644
--- a/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/default.pass.cpp
+++ b/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/default.pass.cpp
@@ -25,8 +25,10 @@ test()
     assert(i1 == I());
 }
 
-int main()
+int main(int, char**)
 {
     test<char>();
     test<wchar_t>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/init.fail.cpp b/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/init.fail.cpp
index 87a227af05804283d928af4465149239d4bc4c67..b6913e6b32d125d22912e73cc28f76a0e07f5c35 100644
--- a/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/init.fail.cpp
+++ b/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/init.fail.cpp
@@ -24,7 +24,7 @@
 #error
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         std::regex phone_numbers("\\d{3}-(\\d{4})");
@@ -32,4 +32,6 @@ int main()
         std::cregex_token_iterator i(std::begin(phone_book), std::end(phone_book)-1,
                                       std::regex("\\d{3}-\\d{4}"), {-1, 0, 1});
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/init.pass.cpp b/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/init.pass.cpp
index 8ecd0bab44f4e6b0b5a164a5d2240918ede2df8d..322c2682daf7674cd451f3fe898960a62cd4a029 100644
--- a/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/init.pass.cpp
+++ b/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/init.pass.cpp
@@ -22,7 +22,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::regex phone_numbers("\\d{3}-(\\d{4})");
@@ -61,4 +61,6 @@ int main()
         ++i;
         assert(i == std::cregex_token_iterator());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/int.fail.cpp b/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/int.fail.cpp
index 82e0678182fab8e8a681fd12c65c03a61ee02776..3c39d4983e26c6f153952bd728c986f9644c8f08 100644
--- a/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/int.fail.cpp
+++ b/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/int.fail.cpp
@@ -23,7 +23,7 @@
 #error
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         std::regex phone_numbers("\\d{3}-\\d{4}");
@@ -31,4 +31,6 @@ int main()
         std::cregex_token_iterator i(std::begin(phone_book), std::end(phone_book)-1,
                                      std::regex("\\d{3}-\\d{4}"), -1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/int.pass.cpp b/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/int.pass.cpp
index c2213a0af48ed31e17a79e366deff2432b9b0d84..1e5ba2eca12a0617079b1cfb3e2b29da33a6fb78 100644
--- a/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/int.pass.cpp
+++ b/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/int.pass.cpp
@@ -19,7 +19,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::regex phone_numbers("\\d{3}-\\d{4}");
@@ -72,4 +72,6 @@ int main()
         ++i;
         assert(i == std::cregex_token_iterator());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/vector.fail.cpp b/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/vector.fail.cpp
index 9e8fe86ed28ea87d075c3ae49b9332eae647fd16..9b07df9d1a7831612092f910d46424fd55d91d72 100644
--- a/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/vector.fail.cpp
+++ b/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/vector.fail.cpp
@@ -25,7 +25,7 @@
 #error
 #endif
 
-int main()
+int main(int, char**)
 {
     {
          std::regex phone_numbers("\\d{3}-(\\d{4})");
@@ -36,4 +36,6 @@ int main()
         std::cregex_token_iterator i(std::begin(phone_book), std::end(phone_book)-1,
                                      std::regex("\\d{3}-\\d{4}"), v);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/vector.pass.cpp b/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/vector.pass.cpp
index 5f31c5795338922a3609175edf0b49299d8529f6..1d77deb918583cd360cef97452cbd7c02f2d5874 100644
--- a/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/vector.pass.cpp
+++ b/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.cnstr/vector.pass.cpp
@@ -20,7 +20,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::regex phone_numbers("\\d{3}-(\\d{4})");
@@ -125,4 +125,6 @@ int main()
         ++i;
         assert(i == std::cregex_token_iterator());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.comp/equal.pass.cpp b/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.comp/equal.pass.cpp
index f4de410b2114d791348f6790cb38591ff2a157be..1c602010319e8f9b19d23e8c07fbf2edcaf0b827 100644
--- a/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.comp/equal.pass.cpp
+++ b/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.comp/equal.pass.cpp
@@ -17,7 +17,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::regex phone_numbers("\\d{3}-\\d{4}");
@@ -33,4 +33,6 @@ int main()
         assert(!(i2 == i));
         assert(i2 != i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.deref/deref.pass.cpp b/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.deref/deref.pass.cpp
index edde79c16419fdc4343aff66caaa500b13335532..facd243675b0c2072b59255c245cefb09f10e58f 100644
--- a/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.deref/deref.pass.cpp
+++ b/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.deref/deref.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::regex phone_numbers("\\d{3}-\\d{4}");
@@ -69,4 +69,6 @@ int main()
         ++i;
         assert(i == std::cregex_token_iterator());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.incr/post.pass.cpp b/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.incr/post.pass.cpp
index c4095ebf6ec210cb5f6eb3ba2e1511061f989dd6..15f1bb7c8516707da36e654edb27c3b3e4961a8e 100644
--- a/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.incr/post.pass.cpp
+++ b/libcxx/test/std/re/re.iter/re.tokiter/re.tokiter.incr/post.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::regex phone_numbers("\\d{3}-\\d{4}");
@@ -132,4 +132,6 @@ int main()
         i++;
         assert(i == std::cregex_token_iterator());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.iter/re.tokiter/types.pass.cpp b/libcxx/test/std/re/re.iter/re.tokiter/types.pass.cpp
index 58803aa1ad32319d644a7a81865af707429520a4..73ad58f4eecfb6a7400568e6744b82ac74d5193a 100644
--- a/libcxx/test/std/re/re.iter/re.tokiter/types.pass.cpp
+++ b/libcxx/test/std/re/re.iter/re.tokiter/types.pass.cpp
@@ -38,8 +38,10 @@ test()
     static_assert((std::is_same<typename I::iterator_category, std::forward_iterator_tag>::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     test<char>();
     test<wchar_t>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.assign/assign.il.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.assign/assign.il.pass.cpp
index daaac65bed6432e88e8e5e76259b51973f154c17..532a72073e689a64c5e073be64f59283959a07d6 100644
--- a/libcxx/test/std/re/re.regex/re.regex.assign/assign.il.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.assign/assign.il.pass.cpp
@@ -20,7 +20,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     std::regex r2;
     r2.assign({'(', 'a', '(', '[', 'b', 'c', ']', ')', ')'});
@@ -30,4 +30,6 @@ int main()
     r2.assign({'(', 'a', '(', '[', 'b', 'c', ']', ')', ')'}, std::regex::extended);
     assert(r2.flags() == std::regex::extended);
     assert(r2.mark_count() == 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.assign/assign.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.assign/assign.pass.cpp
index 9507ea310120ace2c8eba079d114144572624fff..c580ab96cbab098abb20c2c65d53f516709a9f54 100644
--- a/libcxx/test/std/re/re.regex/re.regex.assign/assign.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.assign/assign.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     std::regex r1("(a([bc]))");
     std::regex r2;
@@ -34,4 +34,6 @@ int main()
     assert(r2.mark_count() == 2);
     assert(std::regex_search("ab", r2));
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.assign/assign_iter_iter_flag.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.assign/assign_iter_iter_flag.pass.cpp
index 9eba95b33bfe9aee4132d6b97c55a4da0f16ff07..dd32c9466df2de3e079fec5be5837ecae6b6d036 100644
--- a/libcxx/test/std/re/re.regex/re.regex.assign/assign_iter_iter_flag.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.assign/assign_iter_iter_flag.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_macros.h"
 #include "test_iterators.h"
 
-int main()
+int main(int, char**)
 {
     typedef input_iterator<std::string::const_iterator> I;
     typedef forward_iterator<std::string::const_iterator> F;
@@ -43,4 +43,6 @@ int main()
     r2.assign(F(s4.begin()), F(s4.end()), std::regex::extended);
     assert(r2.flags() == std::regex::extended);
     assert(r2.mark_count() == 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.assign/assign_ptr_flag.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.assign/assign_ptr_flag.pass.cpp
index 30c7281daccb7722b22255d27273edf43f44354d..9445bbaf9ff6f93869df3c894da67f3084db1239 100644
--- a/libcxx/test/std/re/re.regex/re.regex.assign/assign_ptr_flag.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.assign/assign_ptr_flag.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     std::regex r2;
     r2.assign("(a([bc]))");
@@ -26,4 +26,6 @@ int main()
     r2.assign("(a([bc]))", std::regex::extended);
     assert(r2.flags() == std::regex::extended);
     assert(r2.mark_count() == 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.assign/assign_ptr_size_flag.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.assign/assign_ptr_size_flag.pass.cpp
index 08fdf871dcc98ec6e52d511cfb692d7a57ebd720..cdbdae430543b50d74f925e8b1108fc1ae8739e5 100644
--- a/libcxx/test/std/re/re.regex/re.regex.assign/assign_ptr_size_flag.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.assign/assign_ptr_size_flag.pass.cpp
@@ -16,10 +16,12 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     std::regex r2;
     r2.assign("(a([bc]))", 9, std::regex::extended);
     assert(r2.flags() == std::regex::extended);
     assert(r2.mark_count() == 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.assign/assign_string_flag.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.assign/assign_string_flag.pass.cpp
index 7ea385967c346ef1b0afadcec17cf9ca3c15700c..4b1bcef9a6b3b3c4bb324ef676c09d1ac02a2e56 100644
--- a/libcxx/test/std/re/re.regex/re.regex.assign/assign_string_flag.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.assign/assign_string_flag.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     std::regex r2;
     r2.assign(std::string("(a([bc]))"));
@@ -28,4 +28,6 @@ int main()
     r2.assign(std::string("(a([bc]))"), std::regex::extended);
     assert(r2.flags() == std::regex::extended);
     assert(r2.mark_count() == 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.assign/copy.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.assign/copy.pass.cpp
index c74f0a6f029c025594f0fedc5284184f415add9c..1abb72151651642c89438ead25e64ae9908173cd 100644
--- a/libcxx/test/std/re/re.regex/re.regex.assign/copy.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.assign/copy.pass.cpp
@@ -16,11 +16,13 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     std::regex r1("(a([bc]))");
     std::regex r2;
     r2 = r1;
     assert(r2.flags() == std::regex::ECMAScript);
     assert(r2.mark_count() == 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.assign/il.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.assign/il.pass.cpp
index 75803e6002d6be7dd385040c4df7905e1801c3e3..880fd5c79c8b3154d9cc309a71897eac024b7332 100644
--- a/libcxx/test/std/re/re.regex/re.regex.assign/il.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.assign/il.pass.cpp
@@ -18,10 +18,12 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     std::regex r2;
     r2 = {'(', 'a', '(', '[', 'b', 'c', ']', ')', ')'};
     assert(r2.flags() == std::regex::ECMAScript);
     assert(r2.mark_count() == 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.assign/ptr.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.assign/ptr.pass.cpp
index f2ca05a9bfef7a3dc25f19cea979f77f3db26221..3791f81527283aebd62f6f9a59225abb3fb31671 100644
--- a/libcxx/test/std/re/re.regex/re.regex.assign/ptr.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.assign/ptr.pass.cpp
@@ -16,10 +16,12 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     std::regex r2;
     r2 = "(a([bc]))";
     assert(r2.flags() == std::regex::ECMAScript);
     assert(r2.mark_count() == 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.assign/string.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.assign/string.pass.cpp
index 3cb8e8b41be7d4274baf3e8831d24b1b4e1cf378..e33819ab3c37ee397cf8671f53ebc2bc0416f000 100644
--- a/libcxx/test/std/re/re.regex/re.regex.assign/string.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.assign/string.pass.cpp
@@ -17,10 +17,12 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     std::regex r2;
     r2 = std::string("(a([bc]))");
     assert(r2.flags() == std::regex::ECMAScript);
     assert(r2.mark_count() == 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.const/constants.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.const/constants.pass.cpp
index 3fc28e4ec9b7c83ee6c16958431d289364b4d6be..5d8d48d0590da3580861c9ef196002b81432c81c 100644
--- a/libcxx/test/std/re/re.regex/re.regex.const/constants.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.const/constants.pass.cpp
@@ -58,8 +58,10 @@ test()
     where(BR::egrep);
 }
 
-int main()
+int main(int, char**)
 {
     test<char>();
     test<wchar_t>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.construct/awk_oct.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.construct/awk_oct.pass.cpp
index eabf8eab9f2f8eb08f662e1353f788d352a03432..2e7eed350c03023d751abe40f8394558049649d4 100644
--- a/libcxx/test/std/re/re.regex/re.regex.construct/awk_oct.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.construct/awk_oct.pass.cpp
@@ -17,7 +17,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using std::regex_constants::awk;
 
@@ -25,4 +25,6 @@ int main()
     assert(std::regex_match("\41", std::regex("\\41", awk)));
     assert(std::regex_match("\141", std::regex("\\141", awk)));
     assert(std::regex_match("\141" "1", std::regex("\\1411", awk)));
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.construct/bad_backref.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.construct/bad_backref.pass.cpp
index cc1b081c7dfd99fde1eb44d9c8e319fc0ecbecdd..0a15b6453c8d3086b2b6b6bbcc7f7a87e1dca32e 100644
--- a/libcxx/test/std/re/re.regex/re.regex.construct/bad_backref.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.construct/bad_backref.pass.cpp
@@ -29,7 +29,7 @@ static bool error_badbackref_thrown(const char *pat)
     return result;
 }
 
-int main()
+int main(int, char**)
 {
     assert(error_badbackref_thrown("\\1abc"));      // no references
     assert(error_badbackref_thrown("ab(c)\\2def")); // only one reference
@@ -41,4 +41,6 @@ int main()
     const char *pat1 = "a(b)c\\1234";
     std::regex re(pat1, pat1 + 7); // extra chars after the end.
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.construct/bad_ctype.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.construct/bad_ctype.pass.cpp
index dc24531cb48ab3fb8528a3f9e1d464a4fb7b8ab0..5752d5cd681cac7057ac9e163bebdc2ae5e61858 100644
--- a/libcxx/test/std/re/re.regex/re.regex.construct/bad_ctype.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.construct/bad_ctype.pass.cpp
@@ -29,8 +29,10 @@ static bool error_ctype_thrown(const char *pat)
     return result;
 }
 
-int main()
+int main(int, char**)
 {
     assert(error_ctype_thrown("[[::]]"));
     assert(error_ctype_thrown("[[:error:]]"));
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.construct/bad_escape.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.construct/bad_escape.pass.cpp
index f9e589ce7c713eece3dd3e9abccbac114f7a0c13..041d55bdf88d922073e1f47547b3fe0b96c79b18 100644
--- a/libcxx/test/std/re/re.regex/re.regex.construct/bad_escape.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.construct/bad_escape.pass.cpp
@@ -29,7 +29,7 @@ static bool error_escape_thrown(const char *pat)
     return result;
 }
 
-int main()
+int main(int, char**)
 {
     assert(error_escape_thrown("[\\a]"));
     assert(error_escape_thrown("\\a"));
@@ -44,4 +44,6 @@ int main()
     assert(!error_escape_thrown("[\\cA]"));
     assert(!error_escape_thrown("\\cA"));
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.construct/bad_repeat.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.construct/bad_repeat.pass.cpp
index 2d07e1e8cf3315fbbe11e04f1c189f439eb034c5..1af8b5ba651d9a54e26c838488abd3bee1270973 100644
--- a/libcxx/test/std/re/re.regex/re.regex.construct/bad_repeat.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.construct/bad_repeat.pass.cpp
@@ -29,7 +29,7 @@ static bool error_badrepeat_thrown(const char *pat)
     return result;
 }
 
-int main()
+int main(int, char**)
 {
     assert(error_badrepeat_thrown("?a"));
     assert(error_badrepeat_thrown("*a"));
@@ -40,4 +40,6 @@ int main()
     assert(error_badrepeat_thrown("*(a+)"));
     assert(error_badrepeat_thrown("+(a+)"));
     assert(error_badrepeat_thrown("{(a+)"));
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.construct/copy.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.construct/copy.pass.cpp
index 588f673bf4fb7bde16ded37a181eb49cb9d1be35..f3db8fe06113bf00e0339fd5e8d4b5b2afd89a24 100644
--- a/libcxx/test/std/re/re.regex/re.regex.construct/copy.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.construct/copy.pass.cpp
@@ -16,10 +16,12 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     std::regex r1("(a([bc]))");
     std::regex r2 = r1;
     assert(r2.flags() == std::regex::ECMAScript);
     assert(r2.mark_count() == 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.construct/deduct.fail.cpp b/libcxx/test/std/re/re.regex/re.regex.construct/deduct.fail.cpp
index 5ece59ad263bde8f87e5fa8340e68e7a961794ae..30ec49c833b0e0765bb2d17476fcc1aa1cde09b5 100644
--- a/libcxx/test/std/re/re.regex/re.regex.construct/deduct.fail.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.construct/deduct.fail.cpp
@@ -24,7 +24,7 @@
 #include <cstddef>
 
 
-int main()
+int main(int, char**)
 {
 //  Test the explicit deduction guides
     {
@@ -41,4 +41,6 @@ int main()
 
 //  Test the implicit deduction guides
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.construct/deduct.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.construct/deduct.pass.cpp
index 5d7493ae640282df2d2c8c17b99e430d99a3c378..47e5a1dba7f609313553d8c19824c4250edf675f 100644
--- a/libcxx/test/std/re/re.regex/re.regex.construct/deduct.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.construct/deduct.pass.cpp
@@ -31,7 +31,7 @@ using namespace std::literals;
 
 struct A {};
 
-int main()
+int main(int, char**)
 {
 
 //  Test the explicit deduction guides
@@ -133,4 +133,6 @@ int main()
     assert(re.flags() == std::regex_constants::grep);
     assert(re.mark_count() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.construct/default.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.construct/default.pass.cpp
index b5c1521fce58aa7f3663d38498cb6f19b373561c..f706229e68370c3514a5b4cb7d5082c6e286b19f 100644
--- a/libcxx/test/std/re/re.regex/re.regex.construct/default.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.construct/default.pass.cpp
@@ -25,8 +25,10 @@ test()
     assert(r.mark_count() == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test<char>();
     test<wchar_t>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.construct/il_flg.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.construct/il_flg.pass.cpp
index aac13147e81afd2b14ae61e5e42f8f7ecf6111d6..aaf5bc25a7cd20af924d1ed9a860d97fd0f37d8d 100644
--- a/libcxx/test/std/re/re.regex/re.regex.construct/il_flg.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.construct/il_flg.pass.cpp
@@ -29,7 +29,7 @@ test(std::initializer_list<char> il, std::regex_constants::syntax_option_type f,
 }
 
 
-int main()
+int main(int, char**)
 {
     std::string s1("\\(a\\)");
     std::string s2("\\(a[bc]\\)");
@@ -65,4 +65,6 @@ int main()
     test({'\\', '(', 'a', '[', 'b', 'c', ']', '\\', ')'}, std::regex_constants::egrep, 0);
     test({'\\', '(', 'a', '\\', '(', '[', 'b', 'c', ']', '\\', ')', '\\', ')'}, std::regex_constants::egrep, 0);
     test({'(', 'a', '(', '[', 'b', 'c', ']', ')', ')'}, std::regex_constants::egrep, 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.construct/iter_iter.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.construct/iter_iter.pass.cpp
index 0b5d0c504133998198f0177837280583c9395662..3dcf29fa00965ff05a8e72f412629ec0ccadfa6c 100644
--- a/libcxx/test/std/re/re.regex/re.regex.construct/iter_iter.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.construct/iter_iter.pass.cpp
@@ -28,7 +28,7 @@ test(Iter first, Iter last, unsigned mc)
     assert(r.mark_count() == mc);
 }
 
-int main()
+int main(int, char**)
 {
     typedef forward_iterator<std::string::const_iterator> F;
     std::string s1("\\(a\\)");
@@ -40,4 +40,6 @@ int main()
     test(F(s2.begin()), F(s2.end()), 0);
     test(F(s3.begin()), F(s3.end()), 0);
     test(F(s4.begin()), F(s4.end()), 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.construct/iter_iter_flg.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.construct/iter_iter_flg.pass.cpp
index 37878347f9597c5200fa926247047642d96c3827..22423c09282075cb48d4f2e94ffa49144e014194 100644
--- a/libcxx/test/std/re/re.regex/re.regex.construct/iter_iter_flg.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.construct/iter_iter_flg.pass.cpp
@@ -29,7 +29,7 @@ test(Iter first, Iter last, std::regex_constants::syntax_option_type f, unsigned
     assert(r.mark_count() == mc);
 }
 
-int main()
+int main(int, char**)
 {
     typedef forward_iterator<std::string::const_iterator> F;
     std::string s1("\\(a\\)");
@@ -66,4 +66,6 @@ int main()
     test(F(s2.begin()), F(s2.end()), std::regex_constants::egrep, 0);
     test(F(s3.begin()), F(s3.end()), std::regex_constants::egrep, 0);
     test(F(s4.begin()), F(s4.end()), std::regex_constants::egrep, 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.construct/ptr.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.construct/ptr.pass.cpp
index 877b9a4c6eef05d5821704301a9182fd286419b8..b71d9eb7f497ce2e50fe05096533465b11ab6121 100644
--- a/libcxx/test/std/re/re.regex/re.regex.construct/ptr.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.construct/ptr.pass.cpp
@@ -25,10 +25,12 @@ test(const CharT* p, unsigned mc)
     assert(r.mark_count() == mc);
 }
 
-int main()
+int main(int, char**)
 {
     test("\\(a\\)", 0);
     test("\\(a[bc]\\)", 0);
     test("\\(a\\([bc]\\)\\)", 0);
     test("(a([bc]))", 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.construct/ptr_flg.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.construct/ptr_flg.pass.cpp
index 998f28db89257dfbcdd356d09dc646ce49e7baa9..e918b03116ba91eb9cbd21eea59e55ea4f7aad02 100644
--- a/libcxx/test/std/re/re.regex/re.regex.construct/ptr_flg.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.construct/ptr_flg.pass.cpp
@@ -25,7 +25,7 @@ test(const CharT* p, std::regex_constants::syntax_option_type f, unsigned mc)
     assert(r.mark_count() == mc);
 }
 
-int main()
+int main(int, char**)
 {
     test("\\(a\\)", std::regex_constants::basic, 1);
     test("\\(a[bc]\\)", std::regex_constants::basic, 1);
@@ -56,4 +56,6 @@ int main()
     test("\\(a[bc]\\)", std::regex_constants::egrep, 0);
     test("\\(a\\([bc]\\)\\)", std::regex_constants::egrep, 0);
     test("(a([bc]))", std::regex_constants::egrep, 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.construct/ptr_size.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.construct/ptr_size.pass.cpp
index 03a53b7697932ab1377da6c2efd12739e843125e..29fa3ca57ac2d7c44bebc3d260bf7503ca567997 100644
--- a/libcxx/test/std/re/re.regex/re.regex.construct/ptr_size.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.construct/ptr_size.pass.cpp
@@ -24,7 +24,7 @@ test(const CharT* p, std::size_t len, unsigned mc)
     assert(r.mark_count() == mc);
 }
 
-int main()
+int main(int, char**)
 {
     test("\\(a\\)", 5, 0);
     test("\\(a[bc]\\)", 9, 0);
@@ -35,4 +35,6 @@ int main()
     test("(\0)(b)(c)(d)", 9, 3);
     test("(\0)(b)(c)(d)", 3, 1);
     test("(\0)(b)(c)(d)", 0, 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.construct/ptr_size_flg.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.construct/ptr_size_flg.pass.cpp
index 8546c167355eec923edcc50b028093ec54ef6005..07f3947318ed346921718fb9661b79f73e9181b4 100644
--- a/libcxx/test/std/re/re.regex/re.regex.construct/ptr_size_flg.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.construct/ptr_size_flg.pass.cpp
@@ -26,7 +26,7 @@ test(const CharT* p, std::size_t len, std::regex_constants::syntax_option_type f
     assert(r.mark_count() == mc);
 }
 
-int main()
+int main(int, char**)
 {
     test("\\(a\\)", 5, std::regex_constants::basic, 1);
     test("\\(a[bc]\\)", 9, std::regex_constants::basic, 1);
@@ -57,4 +57,6 @@ int main()
     test("\\(a[bc]\\)", 9, std::regex_constants::egrep, 0);
     test("\\(a\\([bc]\\)\\)", 13, std::regex_constants::egrep, 0);
     test("(a([bc]))", 9, std::regex_constants::egrep, 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.construct/string.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.construct/string.pass.cpp
index 58f607183e941900a35ad3631a43b6d2410f58ba..ecd0451d82b8213edac24b0bb26706710b156faa 100644
--- a/libcxx/test/std/re/re.regex/re.regex.construct/string.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.construct/string.pass.cpp
@@ -26,10 +26,12 @@ test(const String& p, unsigned mc)
     assert(r.mark_count() == mc);
 }
 
-int main()
+int main(int, char**)
 {
     test(std::string("\\(a\\)"), 0);
     test(std::string("\\(a[bc]\\)"), 0);
     test(std::string("\\(a\\([bc]\\)\\)"), 0);
     test(std::string("(a([bc]))"), 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.construct/string_flg.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.construct/string_flg.pass.cpp
index 6d504db3334c967fa42fbd4de9c993f16717af49..b6bd8c53c5ae2245bfedde57b443e0e516cd31e5 100644
--- a/libcxx/test/std/re/re.regex/re.regex.construct/string_flg.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.construct/string_flg.pass.cpp
@@ -27,7 +27,7 @@ test(const String& p, std::regex_constants::syntax_option_type f, unsigned mc)
     assert(r.mark_count() == mc);
 }
 
-int main()
+int main(int, char**)
 {
     test(std::string("\\(a\\)"), std::regex_constants::basic, 1);
     test(std::string("\\(a[bc]\\)"), std::regex_constants::basic, 1);
@@ -58,4 +58,6 @@ int main()
     test(std::string("\\(a[bc]\\)"), std::regex_constants::egrep, 0);
     test(std::string("\\(a\\([bc]\\)\\)"), std::regex_constants::egrep, 0);
     test(std::string("(a([bc]))"), std::regex_constants::egrep, 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.locale/imbue.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.locale/imbue.pass.cpp
index a985a74e945a1656f6a164d90cbb7b4052d6f347..27647f1238b4289a884cbc8cda23ae35083bd487 100644
--- a/libcxx/test/std/re/re.regex/re.regex.locale/imbue.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.locale/imbue.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_macros.h"
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     std::regex r;
     std::locale loc = r.imbue(std::locale(LOCALE_en_US_UTF_8));
@@ -30,4 +30,6 @@ int main()
     loc = r.imbue(std::locale("C"));
     assert(loc.name() == LOCALE_en_US_UTF_8);
     assert(r.getloc().name() == "C");
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.nonmemb/nothing_to_do.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.nonmemb/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/re/re.regex/re.regex.nonmemb/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.nonmemb/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.nonmemb/re.regex.nmswap/swap.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.nonmemb/re.regex.nmswap/swap.pass.cpp
index dc5ad95cb0fe7e4dbba9394b69029e30e0813586..bb3291be6f05f845739675a3a9aa2d10c36b180c 100644
--- a/libcxx/test/std/re/re.regex/re.regex.nonmemb/re.regex.nmswap/swap.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.nonmemb/re.regex.nmswap/swap.pass.cpp
@@ -17,7 +17,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     std::regex r1("(a([bc]))");
     std::regex r2;
@@ -26,4 +26,6 @@ int main()
     assert(r1.mark_count() == 0);
     assert(r2.flags() == std::regex::ECMAScript);
     assert(r2.mark_count() == 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.operations/tested_elsewhere.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.operations/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/re/re.regex/re.regex.operations/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.operations/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/re.regex.swap/swap.pass.cpp b/libcxx/test/std/re/re.regex/re.regex.swap/swap.pass.cpp
index b519edc256bdaa897e49664b665bbb3244564dc0..5092d57c148116cd84cfb268ae2461e6a840c109 100644
--- a/libcxx/test/std/re/re.regex/re.regex.swap/swap.pass.cpp
+++ b/libcxx/test/std/re/re.regex/re.regex.swap/swap.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     std::regex r1("(a([bc]))");
     std::regex r2;
@@ -25,4 +25,6 @@ int main()
     assert(r1.mark_count() == 0);
     assert(r2.flags() == std::regex::ECMAScript);
     assert(r2.mark_count() == 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.regex/types.pass.cpp b/libcxx/test/std/re/re.regex/types.pass.cpp
index 21a563890af24f4cee816647af7521b19e645463..a13ad180d3cb42074cd13094314115776e2f9bdb 100644
--- a/libcxx/test/std/re/re.regex/types.pass.cpp
+++ b/libcxx/test/std/re/re.regex/types.pass.cpp
@@ -23,7 +23,7 @@
 #include <type_traits>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::basic_regex<char>::value_type, char>::value), "");
     static_assert((std::is_same<std::basic_regex<char>::traits_type, std::regex_traits<char> >::value), "");
@@ -38,4 +38,6 @@ int main()
     static_assert((std::is_same<std::basic_regex<wchar_t>::flag_type,
                                 std::regex_constants::syntax_option_type>::value), "");
     static_assert((std::is_same<std::basic_regex<wchar_t>::locale_type, std::locale>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.req/nothing_to_do.pass.cpp b/libcxx/test/std/re/re.req/nothing_to_do.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/std/re/re.req/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/re/re.req/nothing_to_do.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.results/re.results.acc/begin_end.pass.cpp b/libcxx/test/std/re/re.results/re.results.acc/begin_end.pass.cpp
index d83ef300f8199f407569e34b8a83bf5d692f32ca..48fff58b019ee57acc88c7cc0382014a38ac2bb1 100644
--- a/libcxx/test/std/re/re.results/re.results.acc/begin_end.pass.cpp
+++ b/libcxx/test/std/re/re.results/re.results.acc/begin_end.pass.cpp
@@ -33,7 +33,9 @@ test()
         assert(*i == m[j]);
 }
 
-int main()
+int main(int, char**)
 {
     test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.results/re.results.acc/cbegin_cend.pass.cpp b/libcxx/test/std/re/re.results/re.results.acc/cbegin_cend.pass.cpp
index 9b8db258777a281c619834a424a008ac70b230d1..bd9009a8a447cd46a0222448d88d96c3a97c2504 100644
--- a/libcxx/test/std/re/re.results/re.results.acc/cbegin_cend.pass.cpp
+++ b/libcxx/test/std/re/re.results/re.results.acc/cbegin_cend.pass.cpp
@@ -33,7 +33,9 @@ test()
         assert(*i == m[j]);
 }
 
-int main()
+int main(int, char**)
 {
     test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.results/re.results.acc/index.pass.cpp b/libcxx/test/std/re/re.results/re.results.acc/index.pass.cpp
index e3f6215e9f44ce60add3242a1d3510a5ebade81c..a5c25a82c81b1e8cf95192dabb177f3f1dad72a4 100644
--- a/libcxx/test/std/re/re.results/re.results.acc/index.pass.cpp
+++ b/libcxx/test/std/re/re.results/re.results.acc/index.pass.cpp
@@ -46,8 +46,10 @@ test(std::regex_constants::syntax_option_type syntax)
     assert(m[4].matched == false);
 }
 
-int main()
+int main(int, char**)
 {
     test(std::regex_constants::ECMAScript);
     test(std::regex_constants::extended);
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.results/re.results.acc/length.pass.cpp b/libcxx/test/std/re/re.results/re.results.acc/length.pass.cpp
index d7d68c5e03220dd33226c8e67029a8768803e474..266ba692ff4dc82ef5ad2bda2becc33998d4172f 100644
--- a/libcxx/test/std/re/re.results/re.results.acc/length.pass.cpp
+++ b/libcxx/test/std/re/re.results/re.results.acc/length.pass.cpp
@@ -30,7 +30,9 @@ test()
     assert(m.length(4) == m[4].length());
 }
 
-int main()
+int main(int, char**)
 {
     test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.results/re.results.acc/position.pass.cpp b/libcxx/test/std/re/re.results/re.results.acc/position.pass.cpp
index 18aa79a48925ca82cb1d06f84e89ff2a6cd6ce56..34256de3585cc0ac9b204c27cdceb140fffa3630 100644
--- a/libcxx/test/std/re/re.results/re.results.acc/position.pass.cpp
+++ b/libcxx/test/std/re/re.results/re.results.acc/position.pass.cpp
@@ -30,7 +30,9 @@ test()
     assert(m.position(4) == std::distance(s, m[4].first));
 }
 
-int main()
+int main(int, char**)
 {
     test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.results/re.results.acc/prefix.pass.cpp b/libcxx/test/std/re/re.results/re.results.acc/prefix.pass.cpp
index ab389cc45367481f4e2c80ff46fb9cd235b4c519..b2cd48d4db60aa99b446137e525029a1633ac38d 100644
--- a/libcxx/test/std/re/re.results/re.results.acc/prefix.pass.cpp
+++ b/libcxx/test/std/re/re.results/re.results.acc/prefix.pass.cpp
@@ -28,7 +28,9 @@ test()
     assert(m.prefix().matched == true);
 }
 
-int main()
+int main(int, char**)
 {
     test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.results/re.results.acc/str.pass.cpp b/libcxx/test/std/re/re.results/re.results.acc/str.pass.cpp
index ae5f5c7f652b49129e991c67cf393a051a7ce489..ae4387d463aa6d521ff73f44dfc05dbc753ce8ab 100644
--- a/libcxx/test/std/re/re.results/re.results.acc/str.pass.cpp
+++ b/libcxx/test/std/re/re.results/re.results.acc/str.pass.cpp
@@ -30,7 +30,9 @@ test()
     assert(m.str(4) == std::string(m[4]));
 }
 
-int main()
+int main(int, char**)
 {
     test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.results/re.results.acc/suffix.pass.cpp b/libcxx/test/std/re/re.results/re.results.acc/suffix.pass.cpp
index 7e88ab106d1025fce4d620b7c1b4da506472f5b0..c9d3855e9bd74db22114306cc74994a57978b56c 100644
--- a/libcxx/test/std/re/re.results/re.results.acc/suffix.pass.cpp
+++ b/libcxx/test/std/re/re.results/re.results.acc/suffix.pass.cpp
@@ -28,7 +28,9 @@ test()
     assert(m.suffix().matched == true);
 }
 
-int main()
+int main(int, char**)
 {
     test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.results/re.results.all/get_allocator.pass.cpp b/libcxx/test/std/re/re.results/re.results.all/get_allocator.pass.cpp
index 1e0a3ce27c84424eac5a4778e6277be463619bf6..f0dcd7b6d42c369b6a995bbbdebeab05cd7a435c 100644
--- a/libcxx/test/std/re/re.results/re.results.all/get_allocator.pass.cpp
+++ b/libcxx/test/std/re/re.results/re.results.all/get_allocator.pass.cpp
@@ -28,8 +28,10 @@ test(const Allocator& a)
     assert(m.get_allocator() == a);
 }
 
-int main()
+int main(int, char**)
 {
     test<char>(test_allocator<std::sub_match<const char*> >(3));
     test<wchar_t>(test_allocator<std::sub_match<const wchar_t*> >(3));
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.results/re.results.const/allocator.pass.cpp b/libcxx/test/std/re/re.results/re.results.const/allocator.pass.cpp
index f8a5a83fed8db5a084d9817de6b3facb76d2613c..99ecb667b7528f5f76e8921aa201058fd6f1732f 100644
--- a/libcxx/test/std/re/re.results/re.results.const/allocator.pass.cpp
+++ b/libcxx/test/std/re/re.results/re.results.const/allocator.pass.cpp
@@ -28,8 +28,10 @@ test(const Allocator& a)
     assert(m.get_allocator() == a);
 }
 
-int main()
+int main(int, char**)
 {
     test<char>(test_allocator<std::sub_match<const char*> >(3));
     test<wchar_t>(test_allocator<std::sub_match<const wchar_t*> >(3));
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.results/re.results.const/copy.pass.cpp b/libcxx/test/std/re/re.results/re.results.const/copy.pass.cpp
index f6733bdd1480944d105d7e5cbd97fa6bb8ea3526..a1dbea0e84026e0edbaec2d5b258a6fa72d29d99 100644
--- a/libcxx/test/std/re/re.results/re.results.const/copy.pass.cpp
+++ b/libcxx/test/std/re/re.results/re.results.const/copy.pass.cpp
@@ -30,11 +30,13 @@ test(const Allocator& a)
     assert(m1.get_allocator() == m0.get_allocator());
 }
 
-int main()
+int main(int, char**)
 {
     test<char>   (std::allocator<std::sub_match<const char *> >());
     test<wchar_t>(std::allocator<std::sub_match<const wchar_t *> >());
 
     test<char>   (test_allocator<std::sub_match<const char*> >(3));
     test<wchar_t>(test_allocator<std::sub_match<const wchar_t*> >(3));
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.results/re.results.const/copy_assign.pass.cpp b/libcxx/test/std/re/re.results/re.results.const/copy_assign.pass.cpp
index 3429b066beed63601bfaa8223a5dbc3cab4dd65e..943037e752fdc9a2545b6aa6ac5efca7e4067383 100644
--- a/libcxx/test/std/re/re.results/re.results.const/copy_assign.pass.cpp
+++ b/libcxx/test/std/re/re.results/re.results.const/copy_assign.pass.cpp
@@ -34,7 +34,7 @@ test(const Allocator& a)
         assert(m1.get_allocator() == Allocator());
 }
 
-int main()
+int main(int, char**)
 {
     test<char>   (std::allocator<std::sub_match<const char *> >());
     test<wchar_t>(std::allocator<std::sub_match<const wchar_t *> >());
@@ -46,4 +46,6 @@ int main()
 //  other_allocator has POCCA -> true
     test<char>   (other_allocator<std::sub_match<const char*> >(3));
     test<wchar_t>(other_allocator<std::sub_match<const wchar_t*> >(3));
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.results/re.results.const/default.pass.cpp b/libcxx/test/std/re/re.results/re.results.const/default.pass.cpp
index 80f4a0269ebd11d1cd1ea1bc2ac5efbaa9ee1ea7..a70c3441db3f4b73273134533bf26e50f7faea5c 100644
--- a/libcxx/test/std/re/re.results/re.results.const/default.pass.cpp
+++ b/libcxx/test/std/re/re.results/re.results.const/default.pass.cpp
@@ -26,8 +26,10 @@ test()
     assert(m.get_allocator() == std::allocator<std::sub_match<const CharT*> >());
 }
 
-int main()
+int main(int, char**)
 {
     test<char>();
     test<wchar_t>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.results/re.results.const/move.pass.cpp b/libcxx/test/std/re/re.results/re.results.const/move.pass.cpp
index b3d2a0f4179f931f370a1535d5f7e15de8c5f0e0..778e31b26f7ee514ee88fba618e611503325f15a 100644
--- a/libcxx/test/std/re/re.results/re.results.const/move.pass.cpp
+++ b/libcxx/test/std/re/re.results/re.results.const/move.pass.cpp
@@ -35,7 +35,7 @@ test(const Allocator& a)
     assert(m1.get_allocator() == a);
 }
 
-int main()
+int main(int, char**)
 {
     test<char>   (std::allocator<std::sub_match<const char *> >());
     test<wchar_t>(std::allocator<std::sub_match<const wchar_t *> >());
@@ -44,4 +44,6 @@ int main()
     assert(test_alloc_base::moved == 1);
     test<wchar_t>(test_allocator<std::sub_match<const wchar_t*> >(3));
     assert(test_alloc_base::moved == 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.results/re.results.const/move_assign.pass.cpp b/libcxx/test/std/re/re.results/re.results.const/move_assign.pass.cpp
index 55c66e9e196cbe4a1a27f951b8efa961c110b0a9..2a62af8f297784f2bf826ea9878e833a30e3d264 100644
--- a/libcxx/test/std/re/re.results/re.results.const/move_assign.pass.cpp
+++ b/libcxx/test/std/re/re.results/re.results.const/move_assign.pass.cpp
@@ -35,7 +35,7 @@ test(const Allocator& a)
         assert(m1.get_allocator() == Allocator());
 }
 
-int main()
+int main(int, char**)
 {
     test<char>   (std::allocator<std::sub_match<const char *> >());
     test<wchar_t>(std::allocator<std::sub_match<const wchar_t *> >());
@@ -47,4 +47,6 @@ int main()
 //  other_allocator has POCMA -> true
     test<char>   (other_allocator<std::sub_match<const char*> >(3));
     test<wchar_t>(other_allocator<std::sub_match<const wchar_t*> >(3));
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.results/re.results.form/form1.pass.cpp b/libcxx/test/std/re/re.results/re.results.form/form1.pass.cpp
index 6046f9be0958c570957d6de779b9db5173cf7900..f435de8276bb71088319ffb6f17f8f343fa3d6b7 100644
--- a/libcxx/test/std/re/re.results/re.results.form/form1.pass.cpp
+++ b/libcxx/test/std/re/re.results/re.results.form/form1.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_macros.h"
 #include "test_iterators.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::match_results<const char*> m;
@@ -152,4 +152,6 @@ int main()
         assert(r == out + 34);
         assert(std::wstring(out) == L"match: cdefghi, m[1]: efg, m[2]: e");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.results/re.results.form/form2.pass.cpp b/libcxx/test/std/re/re.results/re.results.form/form2.pass.cpp
index 2c9d30eb2e24972c530538d81ca6eec694e0463f..b28c064e105ba5db2eb89fec426b51aea2bbddbf 100644
--- a/libcxx/test/std/re/re.results/re.results.form/form2.pass.cpp
+++ b/libcxx/test/std/re/re.results/re.results.form/form2.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_iterators.h"
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::basic_string<char, std::char_traits<char>, test_allocator<char> > nstr;
     typedef std::basic_string<wchar_t, std::char_traits<wchar_t>, test_allocator<wchar_t> > wstr;
@@ -99,4 +99,6 @@ int main()
         assert(r == out + 34);
         assert(std::wstring(out) == L"match: cdefghi, m[1]: efg, m[2]: e");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.results/re.results.form/form3.pass.cpp b/libcxx/test/std/re/re.results/re.results.form/form3.pass.cpp
index ca1a30732bd1249e74f216e0e8bcf2c7b344a974..62a735ca600b5e80158d399e522bf5e81d2b3ecd 100644
--- a/libcxx/test/std/re/re.results/re.results.form/form3.pass.cpp
+++ b/libcxx/test/std/re/re.results/re.results.form/form3.pass.cpp
@@ -23,7 +23,7 @@
 #include "test_macros.h"
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::basic_string<char, std::char_traits<char>, test_allocator<char> > nstr;
     typedef std::basic_string<wchar_t, std::char_traits<wchar_t>, test_allocator<wchar_t> > wstr;
@@ -82,4 +82,6 @@ int main()
         wstr out = m.format(fmt, std::regex_constants::format_sed);
         assert(out == L"match: cdefghi, m[1]: efg, m[2]: e");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.results/re.results.form/form4.pass.cpp b/libcxx/test/std/re/re.results/re.results.form/form4.pass.cpp
index d46d6248d744b324109cc8ec0ad65bae86d26076..658e788b6395a253b876f95ee4926b04928d44b7 100644
--- a/libcxx/test/std/re/re.results/re.results.form/form4.pass.cpp
+++ b/libcxx/test/std/re/re.results/re.results.form/form4.pass.cpp
@@ -20,7 +20,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::match_results<const char*> m;
@@ -77,4 +77,6 @@ int main()
         std::wstring out = m.format(fmt, std::regex_constants::format_sed);
         assert(out == L"match: cdefghi, m[1]: efg, m[2]: e");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.results/re.results.nonmember/equal.pass.cpp b/libcxx/test/std/re/re.results/re.results.nonmember/equal.pass.cpp
index e0b53609af604b48764f745f32880fb19b15ed04..3723ad4740f477da41223a2e8ff24e95b9c64910 100644
--- a/libcxx/test/std/re/re.results/re.results.nonmember/equal.pass.cpp
+++ b/libcxx/test/std/re/re.results/re.results.nonmember/equal.pass.cpp
@@ -40,7 +40,9 @@ test()
     assert(m1 == m2);
 }
 
-int main()
+int main(int, char**)
 {
     test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.results/re.results.size/empty.fail.cpp b/libcxx/test/std/re/re.results/re.results.size/empty.fail.cpp
index 7a92dd88ef7eea5e776f815c101ff2cc4d10b698..e17c77424656f0970af2ddb1ac79e69b46ce5046 100644
--- a/libcxx/test/std/re/re.results/re.results.size/empty.fail.cpp
+++ b/libcxx/test/std/re/re.results/re.results.size/empty.fail.cpp
@@ -19,8 +19,10 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     std::match_results<const char*> c;
     c.empty();  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.results/re.results.size/empty.pass.cpp b/libcxx/test/std/re/re.results/re.results.size/empty.pass.cpp
index 4644a8afb64fd2257600660920547ec803e05421..7eaed34ac6ab8847192f2372bae7ab394b0e23a6 100644
--- a/libcxx/test/std/re/re.results/re.results.size/empty.pass.cpp
+++ b/libcxx/test/std/re/re.results/re.results.size/empty.pass.cpp
@@ -30,7 +30,9 @@ test()
     assert(m.size() == 3);
 }
 
-int main()
+int main(int, char**)
 {
     test<char>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.results/re.results.size/max_size.pass.cpp b/libcxx/test/std/re/re.results/re.results.size/max_size.pass.cpp
index 5293f45f78e934f1f7ff23732f82a02006361d32..184933d135c76ce07b2aca690df1f121f2cefa8f 100644
--- a/libcxx/test/std/re/re.results/re.results.size/max_size.pass.cpp
+++ b/libcxx/test/std/re/re.results/re.results.size/max_size.pass.cpp
@@ -24,8 +24,10 @@ test()
     assert(m.max_size() > 0);
 }
 
-int main()
+int main(int, char**)
 {
     test<char>();
     test<wchar_t>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.results/re.results.state/ready.pass.cpp b/libcxx/test/std/re/re.results/re.results.state/ready.pass.cpp
index daa1bf33730f9f2fd2e7709e0d025b78a623a3ec..476a66fdfba4726d142adc9cd67331bc8b1cb884 100644
--- a/libcxx/test/std/re/re.results/re.results.state/ready.pass.cpp
+++ b/libcxx/test/std/re/re.results/re.results.state/ready.pass.cpp
@@ -36,8 +36,10 @@ test2()
     assert(m.ready() == true);
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.results/re.results.swap/member_swap.pass.cpp b/libcxx/test/std/re/re.results/re.results.swap/member_swap.pass.cpp
index 9cb6ae4417b3c39718a624f4879ddb4eb599e93d..967fe11c5ac4b336490e80c2b356dce736e2caed 100644
--- a/libcxx/test/std/re/re.results/re.results.swap/member_swap.pass.cpp
+++ b/libcxx/test/std/re/re.results/re.results.swap/member_swap.pass.cpp
@@ -33,7 +33,9 @@ test()
     assert(m2 == m1_save);
 }
 
-int main()
+int main(int, char**)
 {
     test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.results/re.results.swap/non_member_swap.pass.cpp b/libcxx/test/std/re/re.results/re.results.swap/non_member_swap.pass.cpp
index 21724fc49336a9c2768a42ab7f1f4fe492a966eb..59ba59f3d6493a25cc723f6a01f04417ff5caa05 100644
--- a/libcxx/test/std/re/re.results/re.results.swap/non_member_swap.pass.cpp
+++ b/libcxx/test/std/re/re.results/re.results.swap/non_member_swap.pass.cpp
@@ -35,7 +35,9 @@ test()
     assert(m2 == m1_save);
 }
 
-int main()
+int main(int, char**)
 {
     test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.results/types.pass.cpp b/libcxx/test/std/re/re.results/types.pass.cpp
index 3f5a31d0d9d0c9cdc9c61e3f5ea7b603a53b664d..0fd8220843b171f4bccd40db2edddc20a307c397 100644
--- a/libcxx/test/std/re/re.results/types.pass.cpp
+++ b/libcxx/test/std/re/re.results/types.pass.cpp
@@ -44,8 +44,10 @@ test()
     static_assert((std::is_same<typename MR::string_type, std::basic_string<CharT> >::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     test<char>();
     test<wchar_t>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.submatch/re.submatch.members/compare_string_type.pass.cpp b/libcxx/test/std/re/re.submatch/re.submatch.members/compare_string_type.pass.cpp
index 050680ae7f2ec2f3bc36689334fd30dce5c9bc66..6b57a193aeda44d20aad9fc50dd9f0bddfc0ae02 100644
--- a/libcxx/test/std/re/re.submatch/re.submatch.members/compare_string_type.pass.cpp
+++ b/libcxx/test/std/re/re.submatch/re.submatch.members/compare_string_type.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef char CharT;
@@ -44,4 +44,6 @@ int main()
         assert(sm.compare(string()) > 0);
         assert(sm.compare(string(L"123")) == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.submatch/re.submatch.members/compare_sub_match.pass.cpp b/libcxx/test/std/re/re.submatch/re.submatch.members/compare_sub_match.pass.cpp
index 6e7d34d78e5b93b74f33ce4d1cb45fb523ac5050..6d0976bbf216458cfb703db51e7a3fc377be3bb1 100644
--- a/libcxx/test/std/re/re.submatch/re.submatch.members/compare_sub_match.pass.cpp
+++ b/libcxx/test/std/re/re.submatch/re.submatch.members/compare_sub_match.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef char CharT;
@@ -50,4 +50,6 @@ int main()
         sm2.matched = true;
         assert(sm.compare(sm2) == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.submatch/re.submatch.members/compare_value_type_ptr.pass.cpp b/libcxx/test/std/re/re.submatch/re.submatch.members/compare_value_type_ptr.pass.cpp
index 672d4aa32c1fd90d8f98f4cfc88ee6178b6e81de..42e6ab94a17264bf62e93a80c891a6f1100e75aa 100644
--- a/libcxx/test/std/re/re.submatch/re.submatch.members/compare_value_type_ptr.pass.cpp
+++ b/libcxx/test/std/re/re.submatch/re.submatch.members/compare_value_type_ptr.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef char CharT;
@@ -42,4 +42,6 @@ int main()
         assert(sm.compare(L"") > 0);
         assert(sm.compare(L"123") == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.submatch/re.submatch.members/default.pass.cpp b/libcxx/test/std/re/re.submatch/re.submatch.members/default.pass.cpp
index a2473552ea098364ebe70c5eb26c276ecbd6293c..c34591f228430ba2c2e91286e9c4a7400d91ca4a 100644
--- a/libcxx/test/std/re/re.submatch/re.submatch.members/default.pass.cpp
+++ b/libcxx/test/std/re/re.submatch/re.submatch.members/default.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef char CharT;
@@ -30,4 +30,6 @@ int main()
         SM sm;
         assert(sm.matched == false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.submatch/re.submatch.members/length.pass.cpp b/libcxx/test/std/re/re.submatch/re.submatch.members/length.pass.cpp
index 459a8fe912d09bd86efb4da729e04cdc738ac486..5246eb3511bae9eeb77f78d01b485e3c4e5390ca 100644
--- a/libcxx/test/std/re/re.submatch/re.submatch.members/length.pass.cpp
+++ b/libcxx/test/std/re/re.submatch/re.submatch.members/length.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef char CharT;
@@ -40,4 +40,6 @@ int main()
         sm.matched = true;
         assert(sm.length() == 3);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.submatch/re.submatch.members/operator_string.pass.cpp b/libcxx/test/std/re/re.submatch/re.submatch.members/operator_string.pass.cpp
index 47659e59cce346b562a74dec7d3ed247ab0a13bc..051ecc3e873d39777b2d9dda2fff0415f5c11f32 100644
--- a/libcxx/test/std/re/re.submatch/re.submatch.members/operator_string.pass.cpp
+++ b/libcxx/test/std/re/re.submatch/re.submatch.members/operator_string.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef char CharT;
@@ -44,4 +44,6 @@ int main()
         str = sm;
         assert(str == std::wstring(L"123"));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.submatch/re.submatch.members/str.pass.cpp b/libcxx/test/std/re/re.submatch/re.submatch.members/str.pass.cpp
index c09783b80cfbd3074527995414f32b08dec36cc9..af39ee9c30fc9e91ce213972778cd9ac171c2534 100644
--- a/libcxx/test/std/re/re.submatch/re.submatch.members/str.pass.cpp
+++ b/libcxx/test/std/re/re.submatch/re.submatch.members/str.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef char CharT;
@@ -44,4 +44,6 @@ int main()
         str = sm.str();
         assert(str == std::wstring(L"123"));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.submatch/re.submatch.op/compare.pass.cpp b/libcxx/test/std/re/re.submatch/re.submatch.op/compare.pass.cpp
index ad65ec54d30a69feb66e7a60689079aa068363e4..e332a8379837e5fdc01b7486812f4405f26e3814 100644
--- a/libcxx/test/std/re/re.submatch/re.submatch.op/compare.pass.cpp
+++ b/libcxx/test/std/re/re.submatch/re.submatch.op/compare.pass.cpp
@@ -276,7 +276,7 @@ test(const std::basic_string<CharT>& x, const std::basic_string<CharT>& y, bool
     assert((sm1 >= y[0]) == (x >= string(1, y[0])));
 }
 
-int main()
+int main(int, char**)
 {
     test(std::string("123"), std::string("123"));
     test(std::string("1234"), std::string("123"));
@@ -284,4 +284,6 @@ int main()
     test(std::wstring(L"1234"), std::wstring(L"123"));
     test(std::string("123\000" "56", 6), std::string("123\000" "56", 6), false);
     test(std::wstring(L"123\000" L"56", 6), std::wstring(L"123\000" L"56", 6), false);
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.submatch/re.submatch.op/stream.pass.cpp b/libcxx/test/std/re/re.submatch/re.submatch.op/stream.pass.cpp
index 63c7d815c3c19a4ce0d7fce629eaba4028326bae..070266d9e58a2ec928ebead74c0737b0e4e2d0ab 100644
--- a/libcxx/test/std/re/re.submatch/re.submatch.op/stream.pass.cpp
+++ b/libcxx/test/std/re/re.submatch/re.submatch.op/stream.pass.cpp
@@ -35,8 +35,10 @@ test(const std::basic_string<CharT>& s)
     assert(os.str() == s);
 }
 
-int main()
+int main(int, char**)
 {
     test(std::string("123"));
     test(std::wstring(L"123"));
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.submatch/types.pass.cpp b/libcxx/test/std/re/re.submatch/types.pass.cpp
index 8141a5302fbcbefbc986a48d26cb1c6aaaeb1228..831eec1da05bf0fbe5da75c5bc8b24588fc4cea3 100644
--- a/libcxx/test/std/re/re.submatch/types.pass.cpp
+++ b/libcxx/test/std/re/re.submatch/types.pass.cpp
@@ -27,7 +27,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::sub_match<char*> SM;
@@ -61,4 +61,6 @@ int main()
         static_assert((std::is_same<std::ssub_match, std::sub_match<std::string::const_iterator> >::value), "");
         static_assert((std::is_same<std::wssub_match, std::sub_match<std::wstring::const_iterator> >::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.syn/cmatch.pass.cpp b/libcxx/test/std/re/re.syn/cmatch.pass.cpp
index 1e7149bb7da24afb522b9b2656460c1c2ecca69c..7b85a69a2ff828d6468e22d75b99d33890a5b3a9 100644
--- a/libcxx/test/std/re/re.syn/cmatch.pass.cpp
+++ b/libcxx/test/std/re/re.syn/cmatch.pass.cpp
@@ -14,7 +14,9 @@
 #include <type_traits>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::match_results<const char*>, std::cmatch>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.syn/cregex_iterator.pass.cpp b/libcxx/test/std/re/re.syn/cregex_iterator.pass.cpp
index 15c7ea8cfa4252dc711edb54bf8647438e96346f..29fdadeb66921e53ff0867d03d06fce885fa0d73 100644
--- a/libcxx/test/std/re/re.syn/cregex_iterator.pass.cpp
+++ b/libcxx/test/std/re/re.syn/cregex_iterator.pass.cpp
@@ -14,7 +14,9 @@
 #include <type_traits>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::regex_iterator<const char*>, std::cregex_iterator>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.syn/cregex_token_iterator.pass.cpp b/libcxx/test/std/re/re.syn/cregex_token_iterator.pass.cpp
index a5b1bc58340a0be5d08be3f5edd55b166ed47c0b..7ca531dfe633391124d343e0e160f7b060da76af 100644
--- a/libcxx/test/std/re/re.syn/cregex_token_iterator.pass.cpp
+++ b/libcxx/test/std/re/re.syn/cregex_token_iterator.pass.cpp
@@ -14,7 +14,9 @@
 #include <type_traits>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::regex_token_iterator<const char*>, std::cregex_token_iterator>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.syn/csub_match.pass.cpp b/libcxx/test/std/re/re.syn/csub_match.pass.cpp
index 7c3d644fd11f2b44efb4c01f474f81f29ccbbfa1..2ace0b983bf078651894b087b717cd8b6d71d7e5 100644
--- a/libcxx/test/std/re/re.syn/csub_match.pass.cpp
+++ b/libcxx/test/std/re/re.syn/csub_match.pass.cpp
@@ -14,7 +14,9 @@
 #include <type_traits>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::sub_match<const char*>, std::csub_match>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.syn/regex.pass.cpp b/libcxx/test/std/re/re.syn/regex.pass.cpp
index 1fe91ec349b5242beede13d5cdcaeb2ce0526e54..0b4c07b6ff181f495ce5097fca61d85fd761d83a 100644
--- a/libcxx/test/std/re/re.syn/regex.pass.cpp
+++ b/libcxx/test/std/re/re.syn/regex.pass.cpp
@@ -14,7 +14,9 @@
 #include <type_traits>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::basic_regex<char>, std::regex>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.syn/smatch.pass.cpp b/libcxx/test/std/re/re.syn/smatch.pass.cpp
index bee9f9f0d6338c05aa6c81769b9908349d09310d..01fa1e95552b761d73c84f3b6eb25014b1c1524e 100644
--- a/libcxx/test/std/re/re.syn/smatch.pass.cpp
+++ b/libcxx/test/std/re/re.syn/smatch.pass.cpp
@@ -14,7 +14,9 @@
 #include <type_traits>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::match_results<std::string::const_iterator>, std::smatch>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.syn/sregex_iterator.pass.cpp b/libcxx/test/std/re/re.syn/sregex_iterator.pass.cpp
index a691cc799a70c72b97ead69ea512fb5beec73b2d..1ae462c6b77887f5096b990b60d11666b5382fb5 100644
--- a/libcxx/test/std/re/re.syn/sregex_iterator.pass.cpp
+++ b/libcxx/test/std/re/re.syn/sregex_iterator.pass.cpp
@@ -14,7 +14,9 @@
 #include <type_traits>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::regex_iterator<std::string::const_iterator>, std::sregex_iterator>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.syn/sregex_token_iterator.pass.cpp b/libcxx/test/std/re/re.syn/sregex_token_iterator.pass.cpp
index 6d148280d738013c0bbd8d9dd1ff0b62824b0794..4b67b66f2914cc1b4891dd1620bd6ee6484ed75a 100644
--- a/libcxx/test/std/re/re.syn/sregex_token_iterator.pass.cpp
+++ b/libcxx/test/std/re/re.syn/sregex_token_iterator.pass.cpp
@@ -14,7 +14,9 @@
 #include <type_traits>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::regex_token_iterator<std::string::const_iterator>, std::sregex_token_iterator>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.syn/ssub_match.pass.cpp b/libcxx/test/std/re/re.syn/ssub_match.pass.cpp
index 0730d667ef17f9579f68994f7864e5d33eb93656..fe3312968498ee94abc3c7c6bb8cafb46112120d 100644
--- a/libcxx/test/std/re/re.syn/ssub_match.pass.cpp
+++ b/libcxx/test/std/re/re.syn/ssub_match.pass.cpp
@@ -14,7 +14,9 @@
 #include <type_traits>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::sub_match<std::string::const_iterator>, std::ssub_match>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.syn/wcmatch.pass.cpp b/libcxx/test/std/re/re.syn/wcmatch.pass.cpp
index 4c9b7e1f272172578c93f68ac5bdb243e874199a..f373e57ac465ab9c2d2a91bce2a1574faae18587 100644
--- a/libcxx/test/std/re/re.syn/wcmatch.pass.cpp
+++ b/libcxx/test/std/re/re.syn/wcmatch.pass.cpp
@@ -14,7 +14,9 @@
 #include <type_traits>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::match_results<const wchar_t*>, std::wcmatch>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.syn/wcregex_iterator.pass.cpp b/libcxx/test/std/re/re.syn/wcregex_iterator.pass.cpp
index c81aa78c1577c7a99011042e617cf867b678d2cb..3425c98fe8c3eee48c7dabbd5a7c7cbc3d6546b8 100644
--- a/libcxx/test/std/re/re.syn/wcregex_iterator.pass.cpp
+++ b/libcxx/test/std/re/re.syn/wcregex_iterator.pass.cpp
@@ -14,7 +14,9 @@
 #include <type_traits>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::regex_iterator<const wchar_t*>, std::wcregex_iterator>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.syn/wcregex_token_iterator.pass.cpp b/libcxx/test/std/re/re.syn/wcregex_token_iterator.pass.cpp
index 9d407103aab4571bf83236528fe5acbc28de8a37..217653837e0ae9cd02b66408b5f83ccbd3167d9d 100644
--- a/libcxx/test/std/re/re.syn/wcregex_token_iterator.pass.cpp
+++ b/libcxx/test/std/re/re.syn/wcregex_token_iterator.pass.cpp
@@ -14,7 +14,9 @@
 #include <type_traits>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::regex_token_iterator<const wchar_t*>, std::wcregex_token_iterator>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.syn/wcsub_match.pass.cpp b/libcxx/test/std/re/re.syn/wcsub_match.pass.cpp
index 7f18b272f99b35dcaa516860000a0236f6c812a6..86a2103b8bd55699fa1eb26bbde8f5145ddb3ebf 100644
--- a/libcxx/test/std/re/re.syn/wcsub_match.pass.cpp
+++ b/libcxx/test/std/re/re.syn/wcsub_match.pass.cpp
@@ -14,7 +14,9 @@
 #include <type_traits>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::sub_match<const wchar_t*>, std::wcsub_match>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.syn/wregex.pass.cpp b/libcxx/test/std/re/re.syn/wregex.pass.cpp
index 9622b89d6d782d84383081eceaf665d0223f3a77..5be6f6fb59ec8da516982b2a800174fc858cf929 100644
--- a/libcxx/test/std/re/re.syn/wregex.pass.cpp
+++ b/libcxx/test/std/re/re.syn/wregex.pass.cpp
@@ -14,7 +14,9 @@
 #include <type_traits>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::basic_regex<wchar_t>, std::wregex>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.syn/wsmatch.pass.cpp b/libcxx/test/std/re/re.syn/wsmatch.pass.cpp
index 98bcbdc4dcf61c456caf5f1878d557da6525e8fc..760057e6a74581986192258c984e1d1a9b839bf6 100644
--- a/libcxx/test/std/re/re.syn/wsmatch.pass.cpp
+++ b/libcxx/test/std/re/re.syn/wsmatch.pass.cpp
@@ -14,7 +14,9 @@
 #include <type_traits>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::match_results<std::wstring::const_iterator>, std::wsmatch>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.syn/wsregex_iterator.pass.cpp b/libcxx/test/std/re/re.syn/wsregex_iterator.pass.cpp
index 1f733d9050dd73c07e7ab6770c7ea192e838df26..b1d7edf87702e1515689d6b3896a05b34aba1348 100644
--- a/libcxx/test/std/re/re.syn/wsregex_iterator.pass.cpp
+++ b/libcxx/test/std/re/re.syn/wsregex_iterator.pass.cpp
@@ -14,7 +14,9 @@
 #include <type_traits>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::regex_iterator<std::wstring::const_iterator>, std::wsregex_iterator>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.syn/wsregex_token_iterator.pass.cpp b/libcxx/test/std/re/re.syn/wsregex_token_iterator.pass.cpp
index b65e4134589b0d4b104aa75c0579e38ac3fa6c0d..58454a59e938a44f6ef9b63844cf3c7bc8f1020a 100644
--- a/libcxx/test/std/re/re.syn/wsregex_token_iterator.pass.cpp
+++ b/libcxx/test/std/re/re.syn/wsregex_token_iterator.pass.cpp
@@ -14,7 +14,9 @@
 #include <type_traits>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::regex_token_iterator<std::wstring::const_iterator>, std::wsregex_token_iterator>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.syn/wssub_match.pass.cpp b/libcxx/test/std/re/re.syn/wssub_match.pass.cpp
index 8f82b34d295cccd49667a09866eb17a8af7ea47f..7ca6dc7734c5dcf49ac34b3e3379809a714833d1 100644
--- a/libcxx/test/std/re/re.syn/wssub_match.pass.cpp
+++ b/libcxx/test/std/re/re.syn/wssub_match.pass.cpp
@@ -14,7 +14,9 @@
 #include <type_traits>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::sub_match<std::wstring::const_iterator>, std::wssub_match>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.traits/default.pass.cpp b/libcxx/test/std/re/re.traits/default.pass.cpp
index b49cc8647011559b61fd703b07b12e95fdba7bb3..459f044e037a3a36ba0f4a50e83400e386bbe037 100644
--- a/libcxx/test/std/re/re.traits/default.pass.cpp
+++ b/libcxx/test/std/re/re.traits/default.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_macros.h"
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::regex_traits<char> t1;
@@ -36,4 +36,6 @@ int main()
         std::regex_traits<wchar_t> t2;
         assert(t2.getloc().name() == LOCALE_en_US_UTF_8);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.traits/getloc.pass.cpp b/libcxx/test/std/re/re.traits/getloc.pass.cpp
index 82e804dc681c09f9d2dcb6e69bfead199bae9f36..dbc35dec39aa3aa2f810210c67ef71902b3b27f4 100644
--- a/libcxx/test/std/re/re.traits/getloc.pass.cpp
+++ b/libcxx/test/std/re/re.traits/getloc.pass.cpp
@@ -20,7 +20,7 @@
 #include "test_macros.h"
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::regex_traits<char> t1;
@@ -35,4 +35,6 @@ int main()
         std::regex_traits<wchar_t> t2;
         assert(t2.getloc().name() == LOCALE_en_US_UTF_8);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.traits/imbue.pass.cpp b/libcxx/test/std/re/re.traits/imbue.pass.cpp
index d2343f2712e8c8c6cef52d0621c89b06bdb97633..0200ce01e3c0f9b5e47981374050239ce95b5717 100644
--- a/libcxx/test/std/re/re.traits/imbue.pass.cpp
+++ b/libcxx/test/std/re/re.traits/imbue.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_macros.h"
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::regex_traits<char> t;
@@ -29,4 +29,6 @@ int main()
         assert(loc.name() == "C");
         assert(t.getloc().name() == LOCALE_en_US_UTF_8);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.traits/isctype.pass.cpp b/libcxx/test/std/re/re.traits/isctype.pass.cpp
index a2f9e2b93d89cd414758814bde7ecd1640ba4510..1eed193ae00f49c031491c92277da797c92a7af9 100644
--- a/libcxx/test/std/re/re.traits/isctype.pass.cpp
+++ b/libcxx/test/std/re/re.traits/isctype.pass.cpp
@@ -20,7 +20,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::regex_traits<char> t;
@@ -280,4 +280,6 @@ int main()
         assert(!t.isctype(L'-', t.lookup_classname(s.begin(), s.end())));
         assert(!t.isctype(L'@', t.lookup_classname(s.begin(), s.end())));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.traits/length.pass.cpp b/libcxx/test/std/re/re.traits/length.pass.cpp
index 822f781abc46ad78ca69e111c546c8bb87588ebb..dce6284bc195ec54e0f3bea2502c319ee7e0282e 100644
--- a/libcxx/test/std/re/re.traits/length.pass.cpp
+++ b/libcxx/test/std/re/re.traits/length.pass.cpp
@@ -17,7 +17,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     assert(std::regex_traits<char>::length("") == 0);
     assert(std::regex_traits<char>::length("1") == 1);
@@ -28,4 +28,6 @@ int main()
     assert(std::regex_traits<wchar_t>::length(L"1") == 1);
     assert(std::regex_traits<wchar_t>::length(L"12") == 2);
     assert(std::regex_traits<wchar_t>::length(L"123") == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.traits/lookup_classname.pass.cpp b/libcxx/test/std/re/re.traits/lookup_classname.pass.cpp
index 74207a0191b78b05b819dbe408dcd07e5ca03f73..38bafa67ebf1db240e0174c45ec390545c7a5846 100644
--- a/libcxx/test/std/re/re.traits/lookup_classname.pass.cpp
+++ b/libcxx/test/std/re/re.traits/lookup_classname.pass.cpp
@@ -53,7 +53,7 @@ test_w(const char_type* A,
       assert(!matches_underscore && "should not match underscore");
 }
 
-int main()
+int main(int, char**)
 {
 //  if __regex_word is not distinct from all the classes, bad things happen
 //  See https://bugs.llvm.org/show_bug.cgi?id=26476 for an example.
@@ -243,4 +243,6 @@ int main()
     test(L"dig", std::ctype_base::mask());
     test(L"", std::ctype_base::mask());
     test(L"digits", std::ctype_base::mask());
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.traits/lookup_collatename.pass.cpp b/libcxx/test/std/re/re.traits/lookup_collatename.pass.cpp
index 3e1fd860a0bb6e10cdc34dbcfdca0b949a4b8a13..aeb7c50bb8177cbc8da00c0c0764243bad52c1d4 100644
--- a/libcxx/test/std/re/re.traits/lookup_collatename.pass.cpp
+++ b/libcxx/test/std/re/re.traits/lookup_collatename.pass.cpp
@@ -39,7 +39,7 @@ test(const char_type* A, const std::basic_string<char_type>& expected)
     assert(t.lookup_collatename(F(A), F(A + t.length(A))) == expected);
 }
 
-int main()
+int main(int, char**)
 {
     test("NUL", std::string("\x00", 1));
     test("alert", std::string("\x07"));
@@ -192,4 +192,6 @@ int main()
     std::locale::global(std::locale(LOCALE_cs_CZ_ISO8859_2));
     test(L"ch", std::wstring(L"ch"));
     std::locale::global(std::locale("C"));
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.traits/transform.pass.cpp b/libcxx/test/std/re/re.traits/transform.pass.cpp
index 75a6c40c76c46a9316eaf6be9919fec4be09ebb5..0125d419eaec24d556761c66c1c51d2ce8efe0fc 100644
--- a/libcxx/test/std/re/re.traits/transform.pass.cpp
+++ b/libcxx/test/std/re/re.traits/transform.pass.cpp
@@ -25,7 +25,7 @@
 #include "test_iterators.h"
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::regex_traits<char> t;
@@ -45,4 +45,6 @@ int main()
         t.imbue(std::locale(LOCALE_cs_CZ_ISO8859_2));
         assert(t.transform(F(a), F(a+1)) < t.transform(F(B), F(B+1)));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.traits/transform_primary.pass.cpp b/libcxx/test/std/re/re.traits/transform_primary.pass.cpp
index b2dab418a6e01140693ed0e2194648d418126780..e24125e0691eba7284dfe57241f8258e2aed67b1 100644
--- a/libcxx/test/std/re/re.traits/transform_primary.pass.cpp
+++ b/libcxx/test/std/re/re.traits/transform_primary.pass.cpp
@@ -27,7 +27,7 @@
 #include "test_iterators.h"
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::regex_traits<char> t;
@@ -51,4 +51,6 @@ int main()
         assert(t.transform_primary(F(A), F(A+1)) ==
                t.transform_primary(F(Aacute), F(Aacute+1)));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.traits/translate.pass.cpp b/libcxx/test/std/re/re.traits/translate.pass.cpp
index 96c77f97c8a0b353c6e13da5f130ebd8a56fa048..e56af4df37cdcd281e24b4ce0723bee741c61c46 100644
--- a/libcxx/test/std/re/re.traits/translate.pass.cpp
+++ b/libcxx/test/std/re/re.traits/translate.pass.cpp
@@ -17,7 +17,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::regex_traits<char> t;
@@ -31,4 +31,6 @@ int main()
         assert(t.translate(L'B') == L'B');
         assert(t.translate(L'c') == L'c');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.traits/translate_nocase.pass.cpp b/libcxx/test/std/re/re.traits/translate_nocase.pass.cpp
index 893c0cd284ea755cc3784a7dea208458fd85a623..6e9f01d1626984d5cf82ec1b4b192b5f9308ef6d 100644
--- a/libcxx/test/std/re/re.traits/translate_nocase.pass.cpp
+++ b/libcxx/test/std/re/re.traits/translate_nocase.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_macros.h"
 #include "platform_support.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::regex_traits<char> t;
@@ -61,4 +61,6 @@ int main()
         assert(t.translate_nocase(L'\xDA') == L'\xFA');
         assert(t.translate_nocase(L'\xFA') == L'\xFA');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.traits/types.pass.cpp b/libcxx/test/std/re/re.traits/types.pass.cpp
index 0d7a2f29b721dc04e960b60459a700d9278f6b90..c3a8770f01d182c43ead3998eb409ad32e2505b4 100644
--- a/libcxx/test/std/re/re.traits/types.pass.cpp
+++ b/libcxx/test/std/re/re.traits/types.pass.cpp
@@ -21,7 +21,7 @@
 #include <type_traits>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::regex_traits<char>::char_type, char>::value), "");
     static_assert((std::is_same<std::regex_traits<char>::string_type, std::string>::value), "");
@@ -29,4 +29,6 @@ int main()
     static_assert((std::is_same<std::regex_traits<wchar_t>::char_type, wchar_t>::value), "");
     static_assert((std::is_same<std::regex_traits<wchar_t>::string_type, std::wstring>::value), "");
     static_assert((std::is_same<std::regex_traits<wchar_t>::locale_type, std::locale>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/re/re.traits/value.pass.cpp b/libcxx/test/std/re/re.traits/value.pass.cpp
index 89bf9c3527c9365c5b7326d11e2165e87b6f75bd..b7ca1fb7c07a4f818fe59b0aa9cfbc4fa7611d46 100644
--- a/libcxx/test/std/re/re.traits/value.pass.cpp
+++ b/libcxx/test/std/re/re.traits/value.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::regex_traits<char> t;
@@ -122,4 +122,6 @@ int main()
             assert(t.value(c, 16) == -1);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string.hash/enabled_hashes.pass.cpp b/libcxx/test/std/strings/basic.string.hash/enabled_hashes.pass.cpp
index 10504c50151a15e0955957ac347d26a6e0fe47ab..0fecb1bb081ffcf9310ff509fdfccc970cf185db 100644
--- a/libcxx/test/std/strings/basic.string.hash/enabled_hashes.pass.cpp
+++ b/libcxx/test/std/strings/basic.string.hash/enabled_hashes.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "poisoned_hash_helper.hpp"
 
-int main() {
+int main(int, char**) {
   test_library_hash_specializations_available();
   {
     test_hash_enabled_for_type<std::string>();
@@ -30,4 +30,6 @@ int main() {
     test_hash_enabled_for_type<std::u32string>();
 #endif
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string.hash/strings.pass.cpp b/libcxx/test/std/strings/basic.string.hash/strings.pass.cpp
index ea97e64f203bb7feac9f61a1df9f303f6f3afefb..c2a2ef95647243a678da395f95275a1eb916aa8a 100644
--- a/libcxx/test/std/strings/basic.string.hash/strings.pass.cpp
+++ b/libcxx/test/std/strings/basic.string.hash/strings.pass.cpp
@@ -40,7 +40,7 @@ test()
     assert(h(s1) != h(s2));
 }
 
-int main()
+int main(int, char**)
 {
     test<std::string>();
 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
@@ -51,4 +51,6 @@ int main()
     test<std::u32string>();
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
     test<std::wstring>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string.literals/literal.pass.cpp b/libcxx/test/std/strings/basic.string.literals/literal.pass.cpp
index eed5c9420ac635de57878e6b49fa7a84801354fa..a51d0d9ac8c0fc59aa673a9a4761ad7d6154a7c9 100644
--- a/libcxx/test/std/strings/basic.string.literals/literal.pass.cpp
+++ b/libcxx/test/std/strings/basic.string.literals/literal.pass.cpp
@@ -21,7 +21,7 @@
 #endif
 
 
-int main()
+int main(int, char**)
 {
     using namespace std::literals::string_literals;
 
@@ -54,4 +54,6 @@ int main()
     Lfoo  =  L"ABC"s;     assert( Lfoo ==  L"ABC");   assert( Lfoo == std::wstring  ( L"ABC"));
     ufoo  =  u"ABC"s;     assert( ufoo ==  u"ABC");   assert( ufoo == std::u16string( u"ABC"));
     Ufoo  =  U"ABC"s;     assert( Ufoo ==  U"ABC");   assert( Ufoo == std::u32string( U"ABC"));
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string.literals/literal1.fail.cpp b/libcxx/test/std/strings/basic.string.literals/literal1.fail.cpp
index 129d2844777b7bfd597d72ad79d1be733af90224..be4604059fe996b10a2dab9dcb857ddd9bbd31ab 100644
--- a/libcxx/test/std/strings/basic.string.literals/literal1.fail.cpp
+++ b/libcxx/test/std/strings/basic.string.literals/literal1.fail.cpp
@@ -12,9 +12,11 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     using std::string;
 
     string foo  =   ""s;  // should fail w/conversion operator not found
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string.literals/literal1.pass.cpp b/libcxx/test/std/strings/basic.string.literals/literal1.pass.cpp
index 5134ec79aaa0340b07105092ed71884266a75445..92777c4f428fe4708fd230037d3316413d516fc4 100644
--- a/libcxx/test/std/strings/basic.string.literals/literal1.pass.cpp
+++ b/libcxx/test/std/strings/basic.string.literals/literal1.pass.cpp
@@ -12,9 +12,11 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     using namespace std::literals;
 
     std::string foo  =   ""s;
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string.literals/literal2.fail.cpp b/libcxx/test/std/strings/basic.string.literals/literal2.fail.cpp
index 3ebbfa24c137d8ea0f0f9823b1977a68e2f1afa0..54a0a9e405bbe077a5222368a0d74676c2439242 100644
--- a/libcxx/test/std/strings/basic.string.literals/literal2.fail.cpp
+++ b/libcxx/test/std/strings/basic.string.literals/literal2.fail.cpp
@@ -12,7 +12,9 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::string foo  =   ""s;  // should fail w/conversion operator not found
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string.literals/literal2.pass.cpp b/libcxx/test/std/strings/basic.string.literals/literal2.pass.cpp
index ac41ce94c9b5bae23594a7b88ecf803c0d28d2a6..6f73ae9a103765fd42d91b36b3915febc1773a2b 100644
--- a/libcxx/test/std/strings/basic.string.literals/literal2.pass.cpp
+++ b/libcxx/test/std/strings/basic.string.literals/literal2.pass.cpp
@@ -12,9 +12,11 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     using namespace std::literals::string_literals;
 
     std::string foo  =   ""s;
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string.literals/literal3.pass.cpp b/libcxx/test/std/strings/basic.string.literals/literal3.pass.cpp
index c5ca6708addca4ca2708f8f22e1cd40fe7902528..b7a8d55368753a8a1df6ffb7c5e34dd38406e5f7 100644
--- a/libcxx/test/std/strings/basic.string.literals/literal3.pass.cpp
+++ b/libcxx/test/std/strings/basic.string.literals/literal3.pass.cpp
@@ -12,9 +12,11 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     using namespace std;
 
     string foo  =   ""s;
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/allocator_mismatch.fail.cpp b/libcxx/test/std/strings/basic.string/allocator_mismatch.fail.cpp
index ae63acfcec1199e056dbf631569bd69fa26e4bea..1d016991f0c6221958d03274739e2734841bce36 100644
--- a/libcxx/test/std/strings/basic.string/allocator_mismatch.fail.cpp
+++ b/libcxx/test/std/strings/basic.string/allocator_mismatch.fail.cpp
@@ -11,7 +11,9 @@
 
 #include <string>
 
-int main()
+int main(int, char**)
 {
     std::basic_string<char, std::char_traits<char>, std::allocator<int> > s;
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/char.bad.fail.cpp b/libcxx/test/std/strings/basic.string/char.bad.fail.cpp
index d78cb6aad98283cf1fad695d31c01d1d2a4b4b2c..bace91c3222b4514d87dfea674285aae673006d1 100644
--- a/libcxx/test/std/strings/basic.string/char.bad.fail.cpp
+++ b/libcxx/test/std/strings/basic.string/char.bad.fail.cpp
@@ -26,7 +26,7 @@ private:
     int two;
 };
 
-int main()
+int main(int, char**)
 {
     {
 //  array
@@ -49,4 +49,6 @@ int main()
     std::basic_string<NotStandardLayout, test_traits<NotStandardLayout> > s;
 //  expected-error-re@string:* {{static_assert failed{{.*}} "Character type of basic_string must be standard-layout"}}
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.access/at.pass.cpp b/libcxx/test/std/strings/basic.string/string.access/at.pass.cpp
index 6515e2727211b554c9e213a445414526449e1c95..514d1a894cea8b6e327601bdc8f6310b4d8bff2e 100644
--- a/libcxx/test/std/strings/basic.string/string.access/at.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.access/at.pass.cpp
@@ -54,7 +54,7 @@ test(S s, typename S::size_type pos)
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -74,4 +74,6 @@ int main()
     test(S("123"), 3);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.access/back.pass.cpp b/libcxx/test/std/strings/basic.string/string.access/back.pass.cpp
index b4108010ac3719ce170a70cf017266edf887c5de..3831da0845cf88c560f3166b89b455c845294c60 100644
--- a/libcxx/test/std/strings/basic.string/string.access/back.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.access/back.pass.cpp
@@ -31,7 +31,7 @@ test(S s)
     assert(s.back() == typename S::value_type('z'));
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -52,4 +52,6 @@ int main()
         assert(false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.access/db_back.pass.cpp b/libcxx/test/std/strings/basic.string/string.access/db_back.pass.cpp
index 5034bfa11a9e7897ba56ed125a8962db043e2ae3..e1cf707a6f0b10195790fed60a0f803b5107176c 100644
--- a/libcxx/test/std/strings/basic.string/string.access/db_back.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.access/db_back.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -46,8 +46,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/strings/basic.string/string.access/db_cback.pass.cpp b/libcxx/test/std/strings/basic.string/string.access/db_cback.pass.cpp
index ddffb6cd7871a5aeb39227c83e6b7653f9c939e9..e3e6db525e4c360f921bb03d82f324eca878c3db 100644
--- a/libcxx/test/std/strings/basic.string/string.access/db_cback.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.access/db_cback.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -42,8 +42,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/strings/basic.string/string.access/db_cfront.pass.cpp b/libcxx/test/std/strings/basic.string/string.access/db_cfront.pass.cpp
index e171883dc366cb0b7d87dc9c1ca91f033017eeee..c9b2ba7c88ed4c90fbfc02e6b4e3db5acc02e7cd 100644
--- a/libcxx/test/std/strings/basic.string/string.access/db_cfront.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.access/db_cfront.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -42,8 +42,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/strings/basic.string/string.access/db_cindex.pass.cpp b/libcxx/test/std/strings/basic.string/string.access/db_cindex.pass.cpp
index 770ab333c8b4ec7cd18026442c91713c279f9e39..c7b430efc9834e628e178e1de2403df0508c430c 100644
--- a/libcxx/test/std/strings/basic.string/string.access/db_cindex.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.access/db_cindex.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -44,8 +44,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/strings/basic.string/string.access/db_front.pass.cpp b/libcxx/test/std/strings/basic.string/string.access/db_front.pass.cpp
index 7f2db649a1248ce03362afb4a905e06e1dd1d963..73db22405103a266d4c086527365c9bcdcd8bec2 100644
--- a/libcxx/test/std/strings/basic.string/string.access/db_front.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.access/db_front.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -46,8 +46,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/strings/basic.string/string.access/db_index.pass.cpp b/libcxx/test/std/strings/basic.string/string.access/db_index.pass.cpp
index 40318e3988ff924adf07d77774298ab279ed4b87..d3f2e8d28d0eb47ddce3648a91e2a0cac3a7b558 100644
--- a/libcxx/test/std/strings/basic.string/string.access/db_index.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.access/db_index.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -44,8 +44,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/strings/basic.string/string.access/front.pass.cpp b/libcxx/test/std/strings/basic.string/string.access/front.pass.cpp
index 5eee328feca0c6a57356774fb01b9477f05dd35a..d51a12f0a77b5490ff26725efefdde81620f82a0 100644
--- a/libcxx/test/std/strings/basic.string/string.access/front.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.access/front.pass.cpp
@@ -31,7 +31,7 @@ test(S s)
     assert(s.front() == typename S::value_type('z'));
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -52,4 +52,6 @@ int main()
         assert(false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.access/index.pass.cpp b/libcxx/test/std/strings/basic.string/string.access/index.pass.cpp
index d529567c6fb26fa442d6584c3138bc5ec43f657b..3a1224ca301d0a351ce99d91bb9d05165a146ae8 100644
--- a/libcxx/test/std/strings/basic.string/string.access/index.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.access/index.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -59,4 +59,6 @@ int main()
         assert(false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.capacity/capacity.pass.cpp b/libcxx/test/std/strings/basic.string/string.capacity/capacity.pass.cpp
index 9f09dea1d3ef254ead8776e9f8c2290f6fb2b620..02187c5193af9aa2204e7a460d8892a7c2461ee1 100644
--- a/libcxx/test/std/strings/basic.string/string.capacity/capacity.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.capacity/capacity.pass.cpp
@@ -40,7 +40,7 @@ test(S s)
     S::allocator_type::throw_after = INT_MAX;
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::basic_string<char, std::char_traits<char>, test_allocator<char> > S;
@@ -60,4 +60,6 @@ int main()
     assert(s.capacity() > 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.capacity/clear.pass.cpp b/libcxx/test/std/strings/basic.string/string.capacity/clear.pass.cpp
index 4f75e013401ed39893fc90376db7ca58da7aa100..914842bb7a65366ed2a125ea07281856416045d1 100644
--- a/libcxx/test/std/strings/basic.string/string.capacity/clear.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.capacity/clear.pass.cpp
@@ -23,7 +23,7 @@ test(S s)
     assert(s.size() == 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -53,4 +53,6 @@ int main()
     test(s);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.capacity/empty.fail.cpp b/libcxx/test/std/strings/basic.string/string.capacity/empty.fail.cpp
index 2359dea942d107f499bf36151dce36a9a490abc4..1bfa388b7b9c69c80c7d0373de14e8bea17abea8 100644
--- a/libcxx/test/std/strings/basic.string/string.capacity/empty.fail.cpp
+++ b/libcxx/test/std/strings/basic.string/string.capacity/empty.fail.cpp
@@ -20,8 +20,10 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     std::string c;
     c.empty();  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.capacity/empty.pass.cpp b/libcxx/test/std/strings/basic.string/string.capacity/empty.pass.cpp
index 56d925d571c6fcadf500abdfeb77e2e7fb8836dd..47827db7f75c1714d27b138a241300374d768057 100644
--- a/libcxx/test/std/strings/basic.string/string.capacity/empty.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.capacity/empty.pass.cpp
@@ -24,7 +24,7 @@ test(const S& s)
     assert(s.empty() == (s.size() == 0));
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -40,4 +40,6 @@ int main()
     test(S("12345678901234567890123456789012345678901234567890"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.capacity/length.pass.cpp b/libcxx/test/std/strings/basic.string/string.capacity/length.pass.cpp
index 617d81a9205a61e4735b870f5da60fb86fcf6df9..b61ec488e27e3ceeaa31ead8e57487f0f5c396fc 100644
--- a/libcxx/test/std/strings/basic.string/string.capacity/length.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.capacity/length.pass.cpp
@@ -22,7 +22,7 @@ test(const S& s)
     assert(s.length() == s.size());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -38,4 +38,6 @@ int main()
     test(S("12345678901234567890123456789012345678901234567890"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.capacity/max_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.capacity/max_size.pass.cpp
index 68017f45349c9ae2aa2dbbdc996bf5242d04d6a0..8f8c9a3fb428cce0dc14bcbad4c4618c2b8714fc 100644
--- a/libcxx/test/std/strings/basic.string/string.capacity/max_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.capacity/max_size.pass.cpp
@@ -54,7 +54,7 @@ test(const S& s)
     test2(s);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -70,4 +70,6 @@ int main()
     test(S("12345678901234567890123456789012345678901234567890"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.capacity/over_max_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.capacity/over_max_size.pass.cpp
index 414b6742495c8ee2c143c83ea011c581d4bbbb1e..9832df536c9ada5808ab093ea628ad9b2bf0777e 100644
--- a/libcxx/test/std/strings/basic.string/string.capacity/over_max_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.capacity/over_max_size.pass.cpp
@@ -35,7 +35,7 @@ test(const S& s)
     assert ( false );
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -51,4 +51,6 @@ int main()
     test(S("12345678901234567890123456789012345678901234567890"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.capacity/reserve.pass.cpp b/libcxx/test/std/strings/basic.string/string.capacity/reserve.pass.cpp
index 33699a79932d541cbd5da858e609e85fb11502ad..f49125cec98ea4e38ce41137ad7cb0df0627ec71 100644
--- a/libcxx/test/std/strings/basic.string/string.capacity/reserve.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.capacity/reserve.pass.cpp
@@ -65,7 +65,7 @@ test(S s, typename S::size_type res_arg)
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -131,4 +131,6 @@ int main()
     }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.capacity/resize_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.capacity/resize_size.pass.cpp
index ad37dc30a1e40b304c3771c77db4e4ed147d107d..8b545939e3d079bfd4a59140111f6ad25b9aaf44 100644
--- a/libcxx/test/std/strings/basic.string/string.capacity/resize_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.capacity/resize_size.pass.cpp
@@ -43,7 +43,7 @@ test(S s, typename S::size_type n, S expected)
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -85,4 +85,6 @@ int main()
     test(S(), S::npos, S("not going to happen"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.capacity/resize_size_char.pass.cpp b/libcxx/test/std/strings/basic.string/string.capacity/resize_size_char.pass.cpp
index b9005341456b8acb84caa1d56dbf3ac5e144e343..b5e5aff8424ad5c41d95c9eb52be2e8f61e31237 100644
--- a/libcxx/test/std/strings/basic.string/string.capacity/resize_size_char.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.capacity/resize_size_char.pass.cpp
@@ -43,7 +43,7 @@ test(S s, typename S::size_type n, typename S::value_type c, S expected)
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -85,4 +85,6 @@ int main()
     test(S(), S::npos, 'a', S("not going to happen"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.capacity/shrink_to_fit.pass.cpp b/libcxx/test/std/strings/basic.string/string.capacity/shrink_to_fit.pass.cpp
index ee91ac1676b4b841a72d4d42c0ea4c0d693ab53d..2c6ce0df6f9fb3e7c3e37a1427111a13a52c8c7b 100644
--- a/libcxx/test/std/strings/basic.string/string.capacity/shrink_to_fit.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.capacity/shrink_to_fit.pass.cpp
@@ -29,7 +29,7 @@ test(S s)
     assert(s.capacity() >= s.size());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -59,4 +59,6 @@ int main()
     test(s);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.capacity/size.pass.cpp b/libcxx/test/std/strings/basic.string/string.capacity/size.pass.cpp
index 16b236eebb879202120966016550b2e739126fd3..f3f89a5a6d861906516c68de70519936e8245012 100644
--- a/libcxx/test/std/strings/basic.string/string.capacity/size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.capacity/size.pass.cpp
@@ -22,7 +22,7 @@ test(const S& s, typename S::size_type c)
     assert(s.size() == c);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -38,4 +38,6 @@ int main()
     test(S("12345678901234567890123456789012345678901234567890"), 50);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/T_size_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.cons/T_size_size.pass.cpp
index 4f8158ea56d29795640eaba12aecd30e963560f2..38725979f9d082f18166422ed7630d6cb2dcfec6 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/T_size_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/T_size_size.pass.cpp
@@ -91,7 +91,7 @@ test(SV sv, std::size_t pos, std::size_t n, const typename S::allocator_type& a)
 #endif
 }
 
-int main()
+int main(int, char**)
 {
 
     {
@@ -183,4 +183,6 @@ int main()
     S s7(s.data(), 2);     // calls ctor(const char *, len)
     assert(s7 == "AB");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/alloc.pass.cpp b/libcxx/test/std/strings/basic.string/string.cons/alloc.pass.cpp
index a2518a184c0a2c733b89c96ebf10cafa9058fb54..765f61eafb813bb425becc9313da98cfdd6ea35d 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/alloc.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/alloc.pass.cpp
@@ -85,11 +85,13 @@ test2()
 
 #endif
 
-int main()
+int main(int, char**)
 {
     test<std::basic_string<char, std::char_traits<char>, test_allocator<char> > >();
 #if TEST_STD_VER >= 11
     test2<std::basic_string<char, std::char_traits<char>, min_allocator<char> > >();
     test2<std::basic_string<char, std::char_traits<char>, explicit_allocator<char> > >();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/brace_assignment.pass.cpp b/libcxx/test/std/strings/basic.string/string.cons/brace_assignment.pass.cpp
index 44db3c14059e63fb3b10eb0935826734a5bfe31d..5e77e46b2e43fc4080b7d6ba49176d68629705fd 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/brace_assignment.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/brace_assignment.pass.cpp
@@ -18,7 +18,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
   // Test that assignment from {} and {ptr, len} are allowed and are not
   // ambiguous.
@@ -32,4 +32,6 @@ int main()
     s = {"abc", 2};
     assert(s == "ab");
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/char_assignment.pass.cpp b/libcxx/test/std/strings/basic.string/string.cons/char_assignment.pass.cpp
index e3976cffa94b5f5f108d8203121a29024d95428b..53f676e3bb38a19f09fee0366b735a392a4ad1d3 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/char_assignment.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/char_assignment.pass.cpp
@@ -28,7 +28,7 @@ test(S s1, typename S::value_type s2)
     assert(s1.capacity() >= s1.size());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -46,4 +46,6 @@ int main()
     test(S("1234567890123456789012345678901234567890123456789012345678901234567890"), 'a');
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/copy.pass.cpp b/libcxx/test/std/strings/basic.string/string.cons/copy.pass.cpp
index f2cfa8a0e379ee4e71ab06abe95b46f00a98aaac..0024f2defac633856f508b859cdd27466a9fd57f 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/copy.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/copy.pass.cpp
@@ -28,7 +28,7 @@ test(S s1)
     assert(s2.get_allocator() == s1.get_allocator());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef test_allocator<char> A;
@@ -46,4 +46,6 @@ int main()
     test(S("1234567890123456789012345678901234567890123456789012345678901234567890", A()));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/copy_alloc.pass.cpp b/libcxx/test/std/strings/basic.string/string.cons/copy_alloc.pass.cpp
index 57a17e8abb9c94dd66086deb762b525776a473bd..a635f017e804599149c42a8a9e7fd8ce5c7efd24 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/copy_alloc.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/copy_alloc.pass.cpp
@@ -87,7 +87,7 @@ test(S s1, const typename S::allocator_type& a)
     assert(s2.get_allocator() == a);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef test_allocator<char> A;
@@ -127,4 +127,6 @@ int main()
     }
 #endif
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/copy_assignment.pass.cpp b/libcxx/test/std/strings/basic.string/string.cons/copy_assignment.pass.cpp
index a3c1389dafebfd43c1d9baea58724cae9ac71ff7..8b3b7ac04c8eabfe764ee63a5287de63727e091d 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/copy_assignment.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/copy_assignment.pass.cpp
@@ -27,7 +27,7 @@ test(S s1, const S& s2)
     assert(s1.capacity() >= s1.size());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -76,4 +76,6 @@ int main()
     assert(s == "a");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/default_noexcept.pass.cpp b/libcxx/test/std/strings/basic.string/string.cons/default_noexcept.pass.cpp
index 1ab00b60e111ae8b07238ccb82d48adfa706ab09..301876b2c3b60f4a676db3deabb036f15bf2d0cf 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/default_noexcept.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/default_noexcept.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_macros.h"
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::string C;
@@ -35,4 +35,6 @@ int main()
         typedef std::basic_string<char, std::char_traits<char>, limited_allocator<char, 10>> C;
         static_assert(!std::is_nothrow_default_constructible<C>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/dtor_noexcept.pass.cpp b/libcxx/test/std/strings/basic.string/string.cons/dtor_noexcept.pass.cpp
index 5b57fe3cadc708cf506db790fffbd32479199c5d..d1372d2964371afe8de3d3a765b236f29532df74 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/dtor_noexcept.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/dtor_noexcept.pass.cpp
@@ -32,7 +32,7 @@ struct throwing_alloc
 std::string s;
 std::wstring ws;
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::string C;
@@ -48,4 +48,6 @@ int main()
         static_assert(!std::is_nothrow_destructible<C>::value, "");
     }
 #endif // _LIBCPP_VERSION
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/implicit_deduction_guides.pass.cpp b/libcxx/test/std/strings/basic.string/string.cons/implicit_deduction_guides.pass.cpp
index 7eb364e62391bccd184ef4f4e938a1a8b6719515..9e31d3e6f9e17c5a77ccb5974f5d2131e45d1c20 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/implicit_deduction_guides.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/implicit_deduction_guides.pass.cpp
@@ -46,7 +46,7 @@ using BStr = std::basic_string<T, std::char_traits<T>, Alloc>;
 // (13) basic_string(initializer_list<CharT>, A const& = A())
 // (14) basic_string(BSV, A const& = A())
 // (15) basic_string(const T&, size_type, size_type, A const& = A())
-int main()
+int main(int, char**)
 {
   using TestSizeT = test_allocator<char>::size_type;
   { // Testing (1)
@@ -313,4 +313,6 @@ int main()
     ASSERT_SAME_TYPE(decltype(w), ExpectW);
     assert(w == L"cd");
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/initializer_list.pass.cpp b/libcxx/test/std/strings/basic.string/string.cons/initializer_list.pass.cpp
index 3a8914cd3d80501fa9567a23517ca29f184c2e12..a106203d49ca4f26fdfd1657e856bff898943564 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/initializer_list.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/initializer_list.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::string s = {'a', 'b', 'c'};
@@ -40,4 +40,6 @@ int main()
         s = {L'a', L'b', L'c'};
         assert(s == L"abc");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/initializer_list_assignment.pass.cpp b/libcxx/test/std/strings/basic.string/string.cons/initializer_list_assignment.pass.cpp
index 6a512f274137c2a006f4af065c1f70d72489c1f2..dcb9bb911b439838f08186730b9d21e7b7b92afc 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/initializer_list_assignment.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/initializer_list_assignment.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::string s;
@@ -30,4 +30,6 @@ int main()
         s = {'a', 'b', 'c'};
         assert(s == "abc");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/iter_alloc.pass.cpp b/libcxx/test/std/strings/basic.string/string.cons/iter_alloc.pass.cpp
index 6966e6e5d24c63b7e3cef386855548216bdf916a..042018cb53232bd57e1e4e473016ec44899cd050 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/iter_alloc.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/iter_alloc.pass.cpp
@@ -56,7 +56,7 @@ test(It first, It last, const A& a)
     assert(s2.capacity() >= s2.size());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef test_allocator<char> A;
@@ -116,4 +116,6 @@ int main()
     test(input_iterator<const char*>(s), input_iterator<const char*>(s+50), A());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/iter_alloc_deduction.fail.cpp b/libcxx/test/std/strings/basic.string/string.cons/iter_alloc_deduction.fail.cpp
index f87aac5f0e7071ba3b8750d08c5adee54a387623..57fd550ac47c7ad8ce447c2cb8176beb93fb32c8 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/iter_alloc_deduction.fail.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/iter_alloc_deduction.fail.cpp
@@ -35,7 +35,7 @@ class NotAnItertor {};
 template <typename T>
 struct NotAnAllocator { typedef T value_type; };
 
-int main()
+int main(int, char**)
 {
     { // Not an iterator at all
     std::basic_string s1{NotAnItertor{}, NotAnItertor{}, std::allocator<char>{}}; // expected-error {{no viable constructor or deduction guide for deduction of template arguments of 'basic_string'}}
@@ -52,4 +52,6 @@ int main()
     std::basic_string s1{s, s+10, NotAnAllocator<wchar_t>{}}; // expected-error {{no viable constructor or deduction guide for deduction of template arguments of 'basic_string'}}
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/iter_alloc_deduction.pass.cpp b/libcxx/test/std/strings/basic.string/string.cons/iter_alloc_deduction.pass.cpp
index dac9ee33277bdc28586617edbc51372197d8f78b..44daab4fcdc966f366fc37e1ee30dd289d8e5e32 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/iter_alloc_deduction.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/iter_alloc_deduction.pass.cpp
@@ -36,7 +36,7 @@
 #include "../input_iterator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     const char* s = "12345678901234";
@@ -89,4 +89,6 @@ int main()
     assert(s1.size() == 10);
     assert(s1.compare(0, s1.size(), s, s1.size()) == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/move.pass.cpp b/libcxx/test/std/strings/basic.string/string.cons/move.pass.cpp
index 1c11368c7ea7f16c11a2b0c1a8b72e4239e65d50..729c8e806906cf56a13642bc1cdcff33e3151c1a 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/move.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/move.pass.cpp
@@ -32,7 +32,7 @@ test(S s0)
     assert(s2.get_allocator() == s1.get_allocator());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef test_allocator<char> A;
@@ -48,4 +48,6 @@ int main()
     test(S("1", A()));
     test(S("1234567890123456789012345678901234567890123456789012345678901234567890", A()));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/move_alloc.pass.cpp b/libcxx/test/std/strings/basic.string/string.cons/move_alloc.pass.cpp
index e426e2dc85dd38f1cd0b3248b0d58b15317b3b32..63e349e71ce512b9658fe8b827fdb4fd9300ff6d 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/move_alloc.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/move_alloc.pass.cpp
@@ -34,7 +34,7 @@ test(S s0, const typename S::allocator_type& a)
 }
 
 
-int main()
+int main(int, char**)
 {
     {
     typedef test_allocator<char> A;
@@ -74,4 +74,6 @@ int main()
     test(S("1"), A());
     test(S("1234567890123456789012345678901234567890123456789012345678901234567890"), A());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/move_assign_noexcept.pass.cpp b/libcxx/test/std/strings/basic.string/string.cons/move_assign_noexcept.pass.cpp
index 88bc12310712594fd49132624c21ff2a2ece76bb..2a00898c1deac09294a3f9d5c46c948c031cba3b 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/move_assign_noexcept.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/move_assign_noexcept.pass.cpp
@@ -62,7 +62,7 @@ struct some_alloc3
     typedef std::false_type is_always_equal;
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::string C;
@@ -93,4 +93,6 @@ int main()
         static_assert(!std::is_nothrow_move_assignable<C>::value, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/move_assignment.pass.cpp b/libcxx/test/std/strings/basic.string/string.cons/move_assignment.pass.cpp
index b039e79554fa30417f97bf450be84424dddca49a..9684fe7380a48dbdb3fdbf4622c7ad088d33d55b 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/move_assignment.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/move_assignment.pass.cpp
@@ -32,7 +32,7 @@ test(S s1, S s2)
     assert(s1.capacity() >= s1.size());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -70,4 +70,6 @@ int main()
            "1234567890123456789012345678901234567890123456789012345678901234567890"),
          S("abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz"));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/move_noexcept.pass.cpp b/libcxx/test/std/strings/basic.string/string.cons/move_noexcept.pass.cpp
index 374183f99ff3cf7ab61fd3a8816042dc9c938315..ee839cf261c3ffc468c88e1597899b0b86952526 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/move_noexcept.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/move_noexcept.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_macros.h"
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::string C;
@@ -39,4 +39,6 @@ int main()
         static_assert( std::is_nothrow_move_constructible<C>::value, "");
 #endif
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/pointer_alloc.pass.cpp b/libcxx/test/std/strings/basic.string/string.cons/pointer_alloc.pass.cpp
index b68c5228a4ba42ebc4b2783640b34158222e8ce6..d67f1231fd34d50bd697ecf8e8ae4be1873a703d 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/pointer_alloc.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/pointer_alloc.pass.cpp
@@ -51,7 +51,7 @@ test(const charT* s, const A& a)
     assert(s2.capacity() >= s2.size());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef test_allocator<char> A;
@@ -85,4 +85,6 @@ int main()
     test("123456798012345679801234567980123456798012345679801234567980", A());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/pointer_assignment.pass.cpp b/libcxx/test/std/strings/basic.string/string.cons/pointer_assignment.pass.cpp
index 1216f3f18cd0dba06cbf6a71c3b63b37f200081f..4a885485bea5200d2c18711a2993b89f316017a9 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/pointer_assignment.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/pointer_assignment.pass.cpp
@@ -29,7 +29,7 @@ test(S s1, const typename S::value_type* s2)
     assert(s1.capacity() >= s1.size());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -69,4 +69,6 @@ int main()
          "abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/pointer_size_alloc.pass.cpp b/libcxx/test/std/strings/basic.string/string.cons/pointer_size_alloc.pass.cpp
index 96457135ed18201faee3fe0c70f73cb6f7c08a57..75ad883fcf1689f94b7042f32ae6019160f4c9bc 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/pointer_size_alloc.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/pointer_size_alloc.pass.cpp
@@ -48,7 +48,7 @@ test(const charT* s, unsigned n, const A& a)
     assert(s2.capacity() >= s2.size());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef test_allocator<char> A;
@@ -90,4 +90,6 @@ int main()
     assert(s == "a");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/size_char_alloc.pass.cpp b/libcxx/test/std/strings/basic.string/string.cons/size_char_alloc.pass.cpp
index 21ed485ef1353d072d0663786f10c77c0d6e52ef..d509971910f11f692bac749b016099f030336be6 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/size_char_alloc.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/size_char_alloc.pass.cpp
@@ -80,7 +80,7 @@ test(Tp n, Tp c, const A& a)
     assert(s2.capacity() >= s2.size());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef test_allocator<char> A;
@@ -120,4 +120,6 @@ int main()
     test(static_cast<char>(100), static_cast<char>(65), A());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/string_view.fail.cpp b/libcxx/test/std/strings/basic.string/string.cons/string_view.fail.cpp
index d7a054073d405641262e8d4050bac6963f4736f2..61d5b3db4e942c6720e49e3b4da18334ebae35f3 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/string_view.fail.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/string_view.fail.cpp
@@ -15,8 +15,10 @@
 
 void foo ( const string &s ) {}
 
-int main()
+int main(int, char**)
 {
     std::string_view sv = "ABCDE";
     foo(sv);    // requires implicit conversion from string_view to string
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/string_view.pass.cpp b/libcxx/test/std/strings/basic.string/string.cons/string_view.pass.cpp
index f50d9e51981f38ff4c4ffee81f4e218fc2456333..b423c327dca291ad048a014a78ae541990adf301 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/string_view.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/string_view.pass.cpp
@@ -71,7 +71,7 @@ test(std::basic_string_view<charT> sv, const A& a)
   }
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef test_allocator<char> A;
@@ -107,4 +107,6 @@ int main()
     test(SV("123456798012345679801234567980123456798012345679801234567980"), A());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/string_view_assignment.pass.cpp b/libcxx/test/std/strings/basic.string/string.cons/string_view_assignment.pass.cpp
index 9a50f62a7ae2592e06d4819f0b75c53a317bbdbb..942d990ee503f2d45d39b4501abef9206085c2db 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/string_view_assignment.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/string_view_assignment.pass.cpp
@@ -28,7 +28,7 @@ test(S s1, SV sv)
     assert(s1.capacity() >= s1.size());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -70,4 +70,6 @@ int main()
          SV("abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/string_view_deduction.fail.cpp b/libcxx/test/std/strings/basic.string/string.cons/string_view_deduction.fail.cpp
index 23e6668e69cffddd77636ad3776c92094e91cab0..62ce16eca161efc8c9dcacc8b13bf9e9bcfe5a78 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/string_view_deduction.fail.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/string_view_deduction.fail.cpp
@@ -31,10 +31,12 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
     std::string_view sv = "12345678901234";
     std::basic_string s1{sv, 23}; // expected-error {{no viable constructor or deduction guide for deduction of template arguments of 'basic_string'}}
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/string_view_deduction.pass.cpp b/libcxx/test/std/strings/basic.string/string.cons/string_view_deduction.pass.cpp
index ee731581fb6360cdd56652d95b6f12666274426d..b3adc41464f5eddad2d0dd989f9e9a99393d290d 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/string_view_deduction.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/string_view_deduction.pass.cpp
@@ -38,7 +38,7 @@
 #include "../input_iterator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::string_view sv = "12345678901234";
@@ -103,4 +103,6 @@ int main()
     assert(s1.size() == sv.size());
     assert(s1.compare(0, s1.size(), sv.data(), s1.size()) == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/string_view_size_size_deduction.fail.cpp b/libcxx/test/std/strings/basic.string/string.cons/string_view_size_size_deduction.fail.cpp
index ce4e695377fef4767c5b317a6d4f4178bea9627a..cff605677de92581f312b57fe00ddb337724263e 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/string_view_size_size_deduction.fail.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/string_view_size_size_deduction.fail.cpp
@@ -37,10 +37,12 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
     std::string_view sv = "12345678901234";
     std::basic_string s1{sv, 0, 4, 23}; // expected-error {{no viable constructor or deduction guide for deduction of template arguments of 'basic_string'}}
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/string_view_size_size_deduction.pass.cpp b/libcxx/test/std/strings/basic.string/string.cons/string_view_size_size_deduction.pass.cpp
index daba3bd12046eaf192022385498d3badb77b0ba9..983ab78e4ce4d2c59ef5e33de6542f9fd7beb5e4 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/string_view_size_size_deduction.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/string_view_size_size_deduction.pass.cpp
@@ -42,7 +42,7 @@
 #include "../input_iterator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::string_view sv = "12345678901234";
@@ -107,4 +107,6 @@ int main()
     assert(s1.size() == 4);
     assert(s1.compare(0, s1.size(), sv.data(), s1.size()) == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.cons/substr.pass.cpp b/libcxx/test/std/strings/basic.string/string.cons/substr.pass.cpp
index 05c53ac23db33359583bc842563fe9edc88d936b..44f29beec9295e3ad268799e1a112798e266d4d9 100644
--- a/libcxx/test/std/strings/basic.string/string.cons/substr.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.cons/substr.pass.cpp
@@ -140,7 +140,7 @@ void test2583()
 #endif
 #endif
 
-int main()
+int main(int, char**)
 {
     {
     typedef test_allocator<char> A;
@@ -224,4 +224,6 @@ int main()
     test2583();
 #endif
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ends_with/ends_with.char.pass.cpp b/libcxx/test/std/strings/basic.string/string.ends_with/ends_with.char.pass.cpp
index 7d1c26418be4012dba604cdd92c9df6c46e8e1e6..e2afe04202c519afedbd01452968ffa4858666dc 100644
--- a/libcxx/test/std/strings/basic.string/string.ends_with/ends_with.char.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ends_with/ends_with.char.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -30,4 +30,6 @@ int main()
     assert ( s2.ends_with('e'));
     assert (!s2.ends_with('x'));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ends_with/ends_with.ptr.pass.cpp b/libcxx/test/std/strings/basic.string/string.ends_with/ends_with.ptr.pass.cpp
index 87b94042ffe4fb6880df75ab12525ceed5508103..a4f8b1aa39c2521868254e231154071a1b9c431e 100644
--- a/libcxx/test/std/strings/basic.string/string.ends_with/ends_with.ptr.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ends_with/ends_with.ptr.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -59,4 +59,6 @@ int main()
     assert (!sNot.ends_with("abcde"));
     assert ( sNot.ends_with("def"));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ends_with/ends_with.string_view.pass.cpp b/libcxx/test/std/strings/basic.string/string.ends_with/ends_with.string_view.pass.cpp
index 3d75e23dac7c289f2829df16161ee332a5c0ca1f..cbfffcfce98da83bc8370115a47fd38c676bad50 100644
--- a/libcxx/test/std/strings/basic.string/string.ends_with/ends_with.string_view.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ends_with/ends_with.string_view.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -68,4 +68,6 @@ int main()
     assert (!sNot.ends_with(sv5));
     assert ( sNot.ends_with(svNot));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.iterators/begin.pass.cpp b/libcxx/test/std/strings/basic.string/string.iterators/begin.pass.cpp
index eedc9b991a208544d3c13c702bcc39f36de8f5f7..fbae9fab7d2f1b52bc5cabbdbd1266326c8f9074 100644
--- a/libcxx/test/std/strings/basic.string/string.iterators/begin.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.iterators/begin.pass.cpp
@@ -30,7 +30,7 @@ test(S s)
     assert(b == cb);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -44,4 +44,6 @@ int main()
     test(S("123"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.iterators/cbegin.pass.cpp b/libcxx/test/std/strings/basic.string/string.iterators/cbegin.pass.cpp
index 720ba53e73828ff1561372bbb341f110fe02c793..9886d56bbd98bdbb446dfc5082954b886e0fb1ea 100644
--- a/libcxx/test/std/strings/basic.string/string.iterators/cbegin.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.iterators/cbegin.pass.cpp
@@ -27,7 +27,7 @@ test(const S& s)
     assert(cb == s.begin());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -41,4 +41,6 @@ int main()
     test(S("123"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.iterators/cend.pass.cpp b/libcxx/test/std/strings/basic.string/string.iterators/cend.pass.cpp
index 07d885aee884e2101fd61e5b5a230f8825b142b9..1a3d30775f2ef059af4e9b1c65967f856ffc9239 100644
--- a/libcxx/test/std/strings/basic.string/string.iterators/cend.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.iterators/cend.pass.cpp
@@ -23,7 +23,7 @@ test(const S& s)
     assert(ce == s.end());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -37,4 +37,6 @@ int main()
     test(S("123"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.iterators/crbegin.pass.cpp b/libcxx/test/std/strings/basic.string/string.iterators/crbegin.pass.cpp
index 2b8837fd3d2b26d7ef8d724f239db9daa07407a4..687c34368ae8d68d1473768239244f21796af5cd 100644
--- a/libcxx/test/std/strings/basic.string/string.iterators/crbegin.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.iterators/crbegin.pass.cpp
@@ -27,7 +27,7 @@ test(const S& s)
     assert(cb == s.rbegin());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -41,4 +41,6 @@ int main()
     test(S("123"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.iterators/crend.pass.cpp b/libcxx/test/std/strings/basic.string/string.iterators/crend.pass.cpp
index c74b907fe7c12f6d5b696eb21097e89316917a6c..86aaad699d4c5585cf3e81021aed9eaf5e284cc3 100644
--- a/libcxx/test/std/strings/basic.string/string.iterators/crend.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.iterators/crend.pass.cpp
@@ -23,7 +23,7 @@ test(const S& s)
     assert(ce == s.rend());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -37,4 +37,6 @@ int main()
     test(S("123"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.iterators/db_iterators_2.pass.cpp b/libcxx/test/std/strings/basic.string/string.iterators/db_iterators_2.pass.cpp
index 074fa84bd8d784636941a76cc4a3c037ba583c42..469632394763efd874f98c90b43fb3086bb7e71a 100644
--- a/libcxx/test/std/strings/basic.string/string.iterators/db_iterators_2.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.iterators/db_iterators_2.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -44,8 +44,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/strings/basic.string/string.iterators/db_iterators_3.pass.cpp b/libcxx/test/std/strings/basic.string/string.iterators/db_iterators_3.pass.cpp
index 9c63eeafe397abfc0e692eac9db41558c5c65d47..7dbbbbb4cbac7bfab3b4e3faa8753b4f7e0190e6 100644
--- a/libcxx/test/std/strings/basic.string/string.iterators/db_iterators_3.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.iterators/db_iterators_3.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -44,8 +44,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/strings/basic.string/string.iterators/db_iterators_4.pass.cpp b/libcxx/test/std/strings/basic.string/string.iterators/db_iterators_4.pass.cpp
index c01b22662b68bed059b412ab52afdae9e64bdbdf..1a46f86c28d76e3a09beb6408e20546fd85ef5a1 100644
--- a/libcxx/test/std/strings/basic.string/string.iterators/db_iterators_4.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.iterators/db_iterators_4.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string C;
@@ -46,8 +46,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/strings/basic.string/string.iterators/db_iterators_5.pass.cpp b/libcxx/test/std/strings/basic.string/string.iterators/db_iterators_5.pass.cpp
index a5a8d917b933039d6899c4cd038e3ffaee0b172a..77caf1b814a1642bea76d22a816579a617143c23 100644
--- a/libcxx/test/std/strings/basic.string/string.iterators/db_iterators_5.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.iterators/db_iterators_5.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string C;
@@ -50,8 +50,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/strings/basic.string/string.iterators/db_iterators_6.pass.cpp b/libcxx/test/std/strings/basic.string/string.iterators/db_iterators_6.pass.cpp
index b4c7fb38006b42b48a8849d471095eb4d515c0eb..126c3661c39250e0fab1e086ae5efc86489f076f 100644
--- a/libcxx/test/std/strings/basic.string/string.iterators/db_iterators_6.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.iterators/db_iterators_6.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string C;
@@ -48,8 +48,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/strings/basic.string/string.iterators/db_iterators_7.pass.cpp b/libcxx/test/std/strings/basic.string/string.iterators/db_iterators_7.pass.cpp
index 6a262e0f39750e5d1bd099cdc2f1782164da4aa0..f1083a43954c84ec142cd792223ed8a9f379bec6 100644
--- a/libcxx/test/std/strings/basic.string/string.iterators/db_iterators_7.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.iterators/db_iterators_7.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string C;
@@ -48,8 +48,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/strings/basic.string/string.iterators/db_iterators_8.pass.cpp b/libcxx/test/std/strings/basic.string/string.iterators/db_iterators_8.pass.cpp
index f3b5656f7661023c1829d299d63f6b31f5be10a9..c69f8ca4b031431c7dbe935dce2f2f0d11bee683 100644
--- a/libcxx/test/std/strings/basic.string/string.iterators/db_iterators_8.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.iterators/db_iterators_8.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string C;
@@ -44,8 +44,10 @@ int main()
 
 #else
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
 #endif
diff --git a/libcxx/test/std/strings/basic.string/string.iterators/end.pass.cpp b/libcxx/test/std/strings/basic.string/string.iterators/end.pass.cpp
index 8d287f6f799bfbb92d7c621effc80d0dd7fb5ea3..86b00a3706d1501cecf3caaa696a0203a0d1311d 100644
--- a/libcxx/test/std/strings/basic.string/string.iterators/end.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.iterators/end.pass.cpp
@@ -33,7 +33,7 @@ test(S s)
     assert(static_cast<std::size_t>(ce - cs.begin()) == cs.size());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -47,4 +47,6 @@ int main()
     test(S("123"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.iterators/iterators.pass.cpp b/libcxx/test/std/strings/basic.string/string.iterators/iterators.pass.cpp
index 3d907602317c093ffda5e4af9d6f0d0cf7f8167e..08448b1fd89f5af996e93a9786bb75fbd1c64107 100644
--- a/libcxx/test/std/strings/basic.string/string.iterators/iterators.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.iterators/iterators.pass.cpp
@@ -20,7 +20,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     { // N3644 testing
         typedef std::string C;
@@ -83,4 +83,6 @@ int main()
         assert ( !(ii1 != ii2 ));
         assert ( !(ii1 != cii ));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.iterators/rbegin.pass.cpp b/libcxx/test/std/strings/basic.string/string.iterators/rbegin.pass.cpp
index 8de45475f62ad3d6c760ad2fa373f9d1d63f9b8f..479584c3708b948e74d5aae141ea2076c8f5bff4 100644
--- a/libcxx/test/std/strings/basic.string/string.iterators/rbegin.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.iterators/rbegin.pass.cpp
@@ -30,7 +30,7 @@ test(S s)
     assert(b == cb);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -44,4 +44,6 @@ int main()
     test(S("123"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.iterators/rend.pass.cpp b/libcxx/test/std/strings/basic.string/string.iterators/rend.pass.cpp
index 1edcb27af070876c77dd63db3e36470cf4605b1e..9b54058a60d8a652b001e7b372b4b063b1276a5f 100644
--- a/libcxx/test/std/strings/basic.string/string.iterators/rend.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.iterators/rend.pass.cpp
@@ -33,7 +33,7 @@ test(S s)
     assert(static_cast<std::size_t>(ce - cs.rbegin()) == cs.size());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -47,4 +47,6 @@ int main()
     test(S("123"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/nothing_to_do.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_append/T_size_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_append/T_size_size.pass.cpp
index f2848295baf675f83a0ffb61430e922942808353..4375240636218a724e53b573b099157a1bdf2e8a 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_append/T_size_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_append/T_size_size.pass.cpp
@@ -71,7 +71,7 @@ test_npos(S s, SV sv, typename S::size_type pos, S expected)
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -196,4 +196,6 @@ int main()
     s.append(sv, 0, std::string::npos);
     assert(s == "ABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZ");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_append/initializer_list.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_append/initializer_list.pass.cpp
index 04483865d560937f4b338e058525306d2637e149..da74fb4e09c0c6661095679cb90fa45a73627f0a 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_append/initializer_list.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_append/initializer_list.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::string s("123");
@@ -31,4 +31,6 @@ int main()
         s.append({'a', 'b', 'c'});
         assert(s == "123abc");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_append/iterator.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_append/iterator.pass.cpp
index 08f554b34d47d5f32dc78314b65dedfb98f06f05..8f280e828d90523c5c231ee8b157204d54fa4e88 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_append/iterator.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_append/iterator.pass.cpp
@@ -42,7 +42,7 @@ test_exceptions(S s, It first, It last)
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -219,4 +219,6 @@ int main()
     s.append(MoveIt(It(std::begin(p))), MoveIt(It(std::end(p) - 1)));
     assert(s == "ABCD");
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_append/pointer.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_append/pointer.pass.cpp
index dec79a67cd12b9b65c1ae716fda454e41c49d5f0..eba693d0e3d13d3253c07cc79c158afe2d0f7219 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_append/pointer.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_append/pointer.pass.cpp
@@ -26,7 +26,7 @@ test(S s, const typename S::value_type* str, S expected)
     assert(s == expected);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -76,4 +76,6 @@ int main()
     s_long.append(s_long.c_str());
     assert(s_long == "Lorem ipsum dolor sit amet, consectetur/Lorem ipsum dolor sit amet, consectetur/");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_append/pointer_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_append/pointer_size.pass.cpp
index 2fb973ae98353169e94c4153d8cea9054fe44b9d..c214ab7c2ac3d164b8bf16f2a3c5aee5e82d5d91 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_append/pointer_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_append/pointer_size.pass.cpp
@@ -27,7 +27,7 @@ test(S s, const typename S::value_type* str, typename S::size_type n, S expected
     assert(s == expected);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -85,4 +85,6 @@ int main()
     s_long.append(s_long.data(), s_long.size());
     assert(s_long == "Lorem ipsum dolor sit amet, consectetur/Lorem ipsum dolor sit amet, consectetur/");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_append/push_back.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_append/push_back.pass.cpp
index a2b9ad1e470d557cbedba4429506c1e23e2f98fe..f1b34ad6cffb33c3d3287899b15b82cfed3adaeb 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_append/push_back.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_append/push_back.pass.cpp
@@ -31,7 +31,7 @@ test(S s, typename S::value_type c, S expected)
     assert(s == expected);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -56,4 +56,6 @@ int main()
     s.push_back(vl);
     s.push_back(vl);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_append/size_char.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_append/size_char.pass.cpp
index 59d0199a2bf615753214c442451c7ef57da46a59..c406248929172290dd84bc49e86e51c26dac3e5e 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_append/size_char.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_append/size_char.pass.cpp
@@ -26,7 +26,7 @@ test(S s, typename S::size_type n, typename S::value_type c, S expected)
     assert(s == expected);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -60,4 +60,6 @@ int main()
     test(S("12345678901234567890"), 10, 'a', S("12345678901234567890aaaaaaaaaa"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_append/string.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_append/string.pass.cpp
index c0c625f2e22e04f391d3282ad273fa195b7dd5d8..5e551d7a2b12fd14ddabc1183d112bdc20093a17 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_append/string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_append/string.pass.cpp
@@ -26,7 +26,7 @@ test(S s, S str, S expected)
     assert(s == expected);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -85,4 +85,6 @@ int main()
     assert(s == "a");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_append/string_size_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_append/string_size_size.pass.cpp
index 21ddd9bb2254a43a571bbd33c55b4dd6246e3bb3..37985d00115c9c93a48d7d85ae21a52431b59f51 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_append/string_size_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_append/string_size_size.pass.cpp
@@ -71,7 +71,7 @@ test_npos(S s, S str, typename S::size_type pos, S expected)
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -133,4 +133,6 @@ int main()
     test_npos(S(), S("12345"), 5, S(""));
     test_npos(S(), S("12345"), 6, S("not happening"));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_append/string_view.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_append/string_view.pass.cpp
index 301fc77b7044e483c7fb7ee4023d4cc9a6d3b11b..d0fb1cc3315e68727f9139b5aeb0d502255d1589 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_append/string_view.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_append/string_view.pass.cpp
@@ -27,7 +27,7 @@ test(S s, SV sv, S expected)
     assert(s == expected);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -79,4 +79,6 @@ int main()
          S("1234567890123456789012345678901234567890"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/T_size_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/T_size_size.pass.cpp
index b05417122572700e1a99ad95c2726a5f85aabfa5..044b3724041533486fce91529e163568ed0d2e73 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/T_size_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/T_size_size.pass.cpp
@@ -70,7 +70,7 @@ test_npos(S s, SV sv, typename S::size_type pos, S expected)
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -191,4 +191,6 @@ int main()
     s.assign(sv, 0, std::string::npos);
     assert(s == "ABCDEFGHIJKLMNOPQRSTUVWXYZ");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/initializer_list.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/initializer_list.pass.cpp
index 72097dae630e5abf06df1f7f7e6a04dcc6845f8c..692b84b557d89c39af4989d10e89a5ea0f1d4361 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/initializer_list.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/initializer_list.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::string s("123");
@@ -31,4 +31,6 @@ int main()
         s.assign({'a', 'b', 'c'});
         assert(s == "abc");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/iterator.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/iterator.pass.cpp
index 4bf805c99d6a93865d4da5c4bc5a88a40d4f8da4..c03b5efdfd57779519b6b552908a5bd79e6635e9 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/iterator.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/iterator.pass.cpp
@@ -43,7 +43,7 @@ test_exceptions(S s, It first, It last)
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -204,4 +204,6 @@ int main()
     s.assign(p, p + 4);
     assert(s == "ABCD");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/pointer.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/pointer.pass.cpp
index 62a173a186d52cef9763a1930399504904919da4..325c354c56ae70254e4fbeda6f15a9e675718209 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/pointer.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/pointer.pass.cpp
@@ -26,7 +26,7 @@ test(S s, const typename S::value_type* str, S expected)
     assert(s == expected);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -74,4 +74,6 @@ int main()
     s_long.assign(s_long.c_str() + 30);
     assert(s_long == "nsectetur/");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/pointer_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/pointer_size.pass.cpp
index 442d8c000245e737359d59880ee458e4447ac9f6..5d3fe262184f5f743aaf3d55b62e64052b8ef8f9 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/pointer_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/pointer_size.pass.cpp
@@ -27,7 +27,7 @@ test(S s, const typename S::value_type* str, typename S::size_type n, S expected
     assert(s == expected);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -85,4 +85,6 @@ int main()
     s_long.assign(s_long.data() + 2, 8 );
     assert(s_long == "rem ipsu");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/rv_string.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/rv_string.pass.cpp
index 3d401c8a917e82144b5a0fc65a41423b696e5896..ac26f369ddb99a610380715172640fd90243c2fd 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/rv_string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/rv_string.pass.cpp
@@ -27,7 +27,7 @@ test(S s, S str, S expected)
     assert(s == expected);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -77,4 +77,6 @@ int main()
          S("12345678901234567890"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/size_char.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/size_char.pass.cpp
index 8c69b138f9fa0929976c39abec5f8ad45e79a190..4e5ecad2e9da830d51921ba07210c5f9fc71a605 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/size_char.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/size_char.pass.cpp
@@ -26,7 +26,7 @@ test(S s, typename S::size_type n, typename S::value_type c, S expected)
     assert(s == expected);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -60,4 +60,6 @@ int main()
     test(S("12345678901234567890"), 10, 'a', S(10, 'a'));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/string.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/string.pass.cpp
index 274703a565d5a8f0d2a5d09695621eafd5aaf2e5..fae45c80de0c6673c80cec50b1aa4b39c9c973ca 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/string.pass.cpp
@@ -37,7 +37,7 @@ testAlloc(S s, S str, const typename S::allocator_type& a)
     assert(s.get_allocator() == a);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -113,4 +113,6 @@ int main()
     static_assert(noexcept(S().assign(S())), "");  // LWG#2063
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/string_size_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/string_size_size.pass.cpp
index 76dd273455ba6a3fed11a61c22c7eed1a0335da1..8e11b150e915623072a3a0fc97a56b66d8117a0a 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/string_size_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/string_size_size.pass.cpp
@@ -71,7 +71,7 @@ test_npos(S s, S str, typename S::size_type pos, S expected)
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -133,4 +133,6 @@ int main()
     test_npos(S(), S("12345"), 5, S(""));
     test_npos(S(), S("12345"), 6, S("not happening"));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/string_view.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/string_view.pass.cpp
index d445ad9b793f7464728c45e7015d5123b6700bde..2d1158e41deba79e19de39aa644e75872351405b 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/string_view.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_assign/string_view.pass.cpp
@@ -38,7 +38,7 @@ testAlloc(S s, SV sv, const typename S::allocator_type& a)
     assert(s.get_allocator() == a);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -101,4 +101,6 @@ int main()
     testAlloc(S(), SV("12345678901234567890"), min_allocator<char>());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_copy/copy.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_copy/copy.pass.cpp
index 81dc3329c43b78cc0dde6dcf4512092f6523ca57..778fb70c069da63fea64bcaa4501c52fa490325c 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_copy/copy.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_copy/copy.pass.cpp
@@ -49,7 +49,7 @@ test(S str, typename S::value_type* s, typename S::size_type n,
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -177,4 +177,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), s, 21, 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/iter.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/iter.pass.cpp
index 1923c62b4d27e0ab4c421e5669eede830d26737b..12b13d738cc4986facaf8a1f1a5bc8a89392e3ab 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/iter.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/iter.pass.cpp
@@ -28,7 +28,7 @@ test(S s, typename S::difference_type pos, S expected)
     assert(i - s.begin() == pos);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -62,4 +62,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), 19, S("abcdefghijklmnopqrs"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/iter_iter.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/iter_iter.pass.cpp
index 0eba9361d8abaf542f5216810956f0e6fd6b5ee0..a5e6d1251d1c616634b954b515fbbca97a3e8c81 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/iter_iter.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/iter_iter.pass.cpp
@@ -29,7 +29,7 @@ test(S s, typename S::difference_type pos, typename S::difference_type n, S expe
     assert(i - s.begin() == pos);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -147,4 +147,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), 20, 0, S("abcdefghijklmnopqrst"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/pop_back.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/pop_back.pass.cpp
index e6f2a4e60351d4e69a749ba0e7b365101b4b1f8c..e6490abcd2eff05c890e0fad11bd6ed10bbbe5fd 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/pop_back.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/pop_back.pass.cpp
@@ -26,7 +26,7 @@ test(S s, S expected)
     assert(s == expected);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -42,4 +42,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), S("abcdefghijklmnopqrs"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/size_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/size_size.pass.cpp
index a8e31c9c6942ed5caee6485b34cebe76a5fbc4c0..88dace52f8af1dc7c317675f6f592572b74eed33 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/size_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/size_size.pass.cpp
@@ -88,7 +88,7 @@ test(S s, S expected)
     assert(s == expected);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -298,4 +298,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), S(""));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/iter_char.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/iter_char.pass.cpp
index d570428c054dd7c11139f1c8bbb8a7fda39278b7..ef6144dadb5c212d20f53d40eb4cdf96dbc28752 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/iter_char.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/iter_char.pass.cpp
@@ -32,7 +32,7 @@ test(S& s, typename S::const_iterator p, typename S::value_type c, S expected)
         assert(i == p);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -72,4 +72,6 @@ int main()
     test(s, s.begin()+6, 'C', S("a567ABC1432dcb"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/iter_initializer_list.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/iter_initializer_list.pass.cpp
index 0acc50b4549867adea5d711a98f8d2894940a258..6dd043c6db93ac40842c7af74ea7ee4165fa2240 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/iter_initializer_list.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/iter_initializer_list.pass.cpp
@@ -18,7 +18,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::string s("123456");
@@ -33,4 +33,6 @@ int main()
         assert(i - s.begin() == 3);
         assert(s == "123abc456");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/iter_iter_iter.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/iter_iter_iter.pass.cpp
index c1b16872928e691f6252185e9c5d8c9cda6d09b5..6d4f1a6686e9e07f691706b1df3cbc032de14b4a 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/iter_iter_iter.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/iter_iter_iter.pass.cpp
@@ -49,7 +49,7 @@ test_exceptions(S s, typename S::difference_type pos, It first, It last)
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -218,4 +218,6 @@ int main()
     s.insert(s.begin(), MoveIt(It(std::begin(p))), MoveIt(It(std::end(p) - 1)));
     assert(s == "ABCD");
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/iter_size_char.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/iter_size_char.pass.cpp
index ac29e3b3325cac3583e3ef62df88d2d8cc3190a2..699b67924b1a8892a78701c2aa1c172644383731 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/iter_size_char.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/iter_size_char.pass.cpp
@@ -28,7 +28,7 @@ test(S s, typename S::difference_type pos, typename S::size_type n,
     assert(s == expected);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -166,4 +166,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), 20, 20, '1', S("abcdefghijklmnopqrst11111111111111111111"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/size_T_size_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/size_T_size_size.pass.cpp
index fb8c7e63a5c2b504ba4443756a038f202ecbbf7f..2b54b67202bcae1cd68d01425822252046851767 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/size_T_size_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/size_T_size_size.pass.cpp
@@ -1729,7 +1729,7 @@ void test30()
     test_npos(S("abcdefghijklmnopqrst"), 10, SV("12345"), 6, S("can't happen"));
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -1838,4 +1838,6 @@ int main()
     assert(s == "");
     s.clear();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/size_pointer.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/size_pointer.pass.cpp
index ee7ef204a33fec430857b6e03d96df93d3f99db2..24859fa8be29a544e5643bb419e2c0b5c9c6186e 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/size_pointer.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/size_pointer.pass.cpp
@@ -47,7 +47,7 @@ test(S s, typename S::size_type pos, const typename S::value_type* str, S expect
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -233,4 +233,6 @@ int main()
     s_long.insert(0, s_long.c_str());
     assert(s_long == "Lorem ipsum dolor sit amet, consectetur/Lorem ipsum dolor sit amet, consectetur/");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/size_pointer_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/size_pointer_size.pass.cpp
index 67a034005283abe3bec09d220ecb237ea5a4c60c..3dbd93f1df5aedcde42828b0c4be759f4b82f733 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/size_pointer_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/size_pointer_size.pass.cpp
@@ -48,7 +48,7 @@ test(S s, typename S::size_type pos, const typename S::value_type* str,
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -714,4 +714,6 @@ int main()
     s_long.insert(0, s_long.data(), s_long.size());
     assert(s_long == "Lorem ipsum dolor sit amet, consectetur/Lorem ipsum dolor sit amet, consectetur/");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/size_size_char.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/size_size_char.pass.cpp
index e64e9c997e3644b5b1b9366c26961421c27e8fc2..dce8b7d7edbabf6bf5e0640ea2b950b532a0bfb1 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/size_size_char.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/size_size_char.pass.cpp
@@ -48,7 +48,7 @@ test(S s, typename S::size_type pos, typename S::size_type n,
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -218,4 +218,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), 21, 20, '1', S("can't happen"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/size_string.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/size_string.pass.cpp
index 2f74fec3f7942ae5628d0ae6227aa8ec903b7256..93bc3f6d961b67cc4e14083f9a047646e60f280c 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/size_string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/size_string.pass.cpp
@@ -47,7 +47,7 @@ test(S s, typename S::size_type pos, S str, S expected)
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -226,4 +226,6 @@ int main()
     assert(s == "a");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/size_string_size_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/size_string_size_size.pass.cpp
index 23b8852b4c38334cffe0bcb0662e76b8affa9895..18a688a5d1f821c58ff4f819f4b76b582d1c6be4 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/size_string_size_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/size_string_size_size.pass.cpp
@@ -1727,7 +1727,7 @@ void test30()
     test_npos(S("abcdefghijklmnopqrst"), 10, S("12345"), 6, S("can't happen"));
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -1799,4 +1799,6 @@ int main()
     test30<S>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/string_view.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/string_view.pass.cpp
index 0596ce9849e50737e5a920b5aad26cd4c1e2654a..129389a9a7b085f9f597f1c1fbb87c52973f1b73 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/string_view.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_insert/string_view.pass.cpp
@@ -47,7 +47,7 @@ test(S s, typename S::size_type pos, SV sv, S expected)
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -235,4 +235,6 @@ int main()
     s_long.insert(0, s_long.c_str());
     assert(s_long == "Lorem ipsum dolor sit amet, consectetur/Lorem ipsum dolor sit amet, consectetur/");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_op_plus_equal/char.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_op_plus_equal/char.pass.cpp
index 3c15f6f919eb1bd1ee9fadba0c00687eeff2f65e..2cc4496eb678fe4fa0c3cf21275550ef3e3cc9a9 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_op_plus_equal/char.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_op_plus_equal/char.pass.cpp
@@ -25,7 +25,7 @@ test(S s, typename S::value_type str, S expected)
     assert(s == expected);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -43,4 +43,6 @@ int main()
     test(S("12345678901234567890"), 'a', S("12345678901234567890a"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_op_plus_equal/initializer_list.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_op_plus_equal/initializer_list.pass.cpp
index 7f27559f0e65323be01b2835b248c2b9547c5b21..689389eb7a64dd6eb2205d012a1e3a76b83c5321 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_op_plus_equal/initializer_list.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_op_plus_equal/initializer_list.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::string s("123");
@@ -30,4 +30,6 @@ int main()
         s += {'a', 'b', 'c'};
         assert(s == "123abc");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_op_plus_equal/pointer.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_op_plus_equal/pointer.pass.cpp
index 3a76969351837e240dc9e9ac62ce338f3ca20e00..a9edf17be5b1a1e652a59433ad7edbf70cac02a2 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_op_plus_equal/pointer.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_op_plus_equal/pointer.pass.cpp
@@ -25,7 +25,7 @@ test(S s, const typename S::value_type* str, S expected)
     assert(s == expected);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -75,4 +75,6 @@ int main()
          S("1234567890123456789012345678901234567890"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_op_plus_equal/string.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_op_plus_equal/string.pass.cpp
index 53e1cacf4a173f915c4495b1112553c3fc5e9137..f81d4bec0d24045c5b9f2aea18d31d2bd1ff6f77 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_op_plus_equal/string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_op_plus_equal/string.pass.cpp
@@ -26,7 +26,7 @@ test(S s, S str, S expected)
     assert(s == expected);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -85,4 +85,6 @@ int main()
     assert(s == "a");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/iter_iter_initializer_list.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/iter_iter_initializer_list.pass.cpp
index 8e8a1f8ef9e85e08789a0b1f4a0f3c28eef5ab0b..3df49f32535b9a7956cd5069874e0dc6cf1f63b6 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/iter_iter_initializer_list.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/iter_iter_initializer_list.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::string s("123def456");
@@ -30,4 +30,6 @@ int main()
         s.replace(s.cbegin() + 3, s.cbegin() + 6, {'a', 'b', 'c'});
         assert(s == "123abc456");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/iter_iter_iter_iter.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/iter_iter_iter_iter.pass.cpp
index fc6f33beafeda15d28c38a1217ed127d5e9f9cd3..47a1193be7327f6c737a4194ffbb6eaf057f3bf3 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/iter_iter_iter_iter.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/iter_iter_iter_iter.pass.cpp
@@ -963,7 +963,7 @@ void test8()
     test(S("abcdefghijklmnopqrst"), 20, 0, str, str+20, S("abcdefghijklmnopqrst12345678901234567890"));
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -1036,4 +1036,6 @@ int main()
     s.replace(s.begin(), s.end(), p, p + 4);
     assert(s == "EFGH");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/iter_iter_pointer.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/iter_iter_pointer.pass.cpp
index ccbd0ff66fbeaa01d88b37015e25011d3757eac9..8ed1dc3df30592b77054ee306128a31cec8b5627 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/iter_iter_pointer.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/iter_iter_pointer.pass.cpp
@@ -265,7 +265,7 @@ void test2()
     test(S("abcdefghijklmnopqrst"), 20, 0, "12345678901234567890", S("abcdefghijklmnopqrst12345678901234567890"));
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -297,4 +297,6 @@ int main()
     s_long.replace(s_long.begin(), s_long.begin(), s_long.c_str());
     assert(s_long == "Lorem ipsum dolor sit amet, consectetur/Lorem ipsum dolor sit amet, consectetur/");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/iter_iter_pointer_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/iter_iter_pointer_size.pass.cpp
index 79ae58fce2ebd70698b456188cd160654ebbbca7..39b518c9146d1d94a6ee7c2f2133b47116e4417c 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/iter_iter_pointer_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/iter_iter_pointer_size.pass.cpp
@@ -943,7 +943,7 @@ void test8()
     test(S("abcdefghijklmnopqrst"), 20, 0, "12345678901234567890", 20, S("abcdefghijklmnopqrst12345678901234567890"));
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -987,4 +987,6 @@ int main()
     s_long.replace(s_long.begin(), s_long.begin(), s_long.data(), s_long.size());
     assert(s_long == "Lorem ipsum dolor sit amet, consectetur/Lorem ipsum dolor sit amet, consectetur/");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/iter_iter_size_char.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/iter_iter_size_char.pass.cpp
index 8a79b733fe22306db9adf6cae4d0b61372e881c7..e60c69f7a275c0bf7cc17b141bbebc9477da7a38 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/iter_iter_size_char.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/iter_iter_size_char.pass.cpp
@@ -265,7 +265,7 @@ void test2()
     test(S("abcdefghijklmnopqrst"), 20, 0, 20, '3', S("abcdefghijklmnopqrst33333333333333333333"));
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -281,4 +281,6 @@ int main()
     test2<S>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/iter_iter_string.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/iter_iter_string.pass.cpp
index b47d2931b9b24a475687fb6214facfed67e56124..7008736610f982a45d7880b5a9d797275c49207e 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/iter_iter_string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/iter_iter_string.pass.cpp
@@ -264,7 +264,7 @@ void test2()
     test(S("abcdefghijklmnopqrst"), 20, 0, S("12345678901234567890"), S("abcdefghijklmnopqrst12345678901234567890"));
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -289,4 +289,6 @@ int main()
     assert(s == "a");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/iter_iter_string_view.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/iter_iter_string_view.pass.cpp
index 81ecca69fb3b43c79a4c6c47349793608a4d1b89..0acf82868532fd34e5f53b0a385e43b11145efe4 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/iter_iter_string_view.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/iter_iter_string_view.pass.cpp
@@ -264,7 +264,7 @@ void test2()
     test(S("abcdefghijklmnopqrst"), 20, 0, SV("12345678901234567890"), S("abcdefghijklmnopqrst12345678901234567890"));
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -282,4 +282,6 @@ int main()
     test2<S, SV>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/size_size_T_size_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/size_size_T_size_size.pass.cpp
index b320eff372c8f9e8a2d7320d41fc43e1692df58d..2348747def08f57f7f9a8100cbf65f8ae1f7062c 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/size_size_T_size_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/size_size_T_size_size.pass.cpp
@@ -5869,7 +5869,7 @@ void test55()
     test_npos(S("abcdefghij"), 9, 2, SV("12345"), 6, S("can't happen"));
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -6025,4 +6025,6 @@ int main()
     s.replace(0, 4, arr, 0, std::string::npos);    // calls replace(pos1, n1, string("IJKL"), pos, npos)
     assert(s == "IJKL");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/size_size_pointer.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/size_size_pointer.pass.cpp
index 6718242e0e8c13e4f8c11291de67020127cb67c0..a6a6c7d9dcf49fe8f6e50537639f5e675a940617 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/size_size_pointer.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/size_size_pointer.pass.cpp
@@ -363,7 +363,7 @@ void test2()
     test(S("abcdefghijklmnopqrst"), 21, 0, "12345678901234567890", S("can't happen"));
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -379,4 +379,6 @@ int main()
     test2<S>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/size_size_pointer_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/size_size_pointer_size.pass.cpp
index 53465bf680e372adf87e849b96dbf3dcae2cfb62..e305667070439e2c933374a306765b86ca8f9daa 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/size_size_pointer_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/size_size_pointer_size.pass.cpp
@@ -1297,7 +1297,7 @@ void test11()
     test(S("abcdefghijklmnopqrst"), 21, 0, "12345678901234567890", 20, S("can't happen"));
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -1331,4 +1331,6 @@ int main()
     test11<S>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/size_size_size_char.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/size_size_size_char.pass.cpp
index 2e8c4527cc7c6dd940e1405e5a6a615524773565..7d37e10756184f99006055132436799a6943ad54 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/size_size_size_char.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/size_size_size_char.pass.cpp
@@ -364,7 +364,7 @@ void test2()
     test(S("abcdefghijklmnopqrst"), 21, 0, 20, '2', S("can't happen"));
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -380,4 +380,6 @@ int main()
     test2<S>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/size_size_string.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/size_size_string.pass.cpp
index 85306d595953d09d7be575d747224a7e8d23433d..c0fad33a39885347d937c4ba78932b971ff9e969 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/size_size_string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/size_size_string.pass.cpp
@@ -362,7 +362,7 @@ void test2()
     test(S("abcdefghijklmnopqrst"), 21, 0, S("12345678901234567890"), S("can't happen"));
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -387,4 +387,6 @@ int main()
     assert(s == "a");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/size_size_string_size_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/size_size_string_size_size.pass.cpp
index 7a75f03e59bea331433b633083f3e449a3285d8e..3fa32699fdaa9a79258e428820e5c3b4f59d0b00 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/size_size_string_size_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/size_size_string_size_size.pass.cpp
@@ -5859,7 +5859,7 @@ void test55()
     test_npos(S("abcdefghij"), 9, 2, S("12345"), 6, S("can't happen"));
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -5981,4 +5981,6 @@ int main()
     test55<S>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/size_size_string_view.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/size_size_string_view.pass.cpp
index 9b35da025f92db35453c039d1516ff83d94cb91a..542220aea7033dc2e2c4d15d86e2944526ff277c 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/size_size_string_view.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_replace/size_size_string_view.pass.cpp
@@ -362,7 +362,7 @@ void test2()
     test(S("abcdefghijklmnopqrst"), 21, 0, SV("12345678901234567890"), S("can't happen"));
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -380,4 +380,6 @@ int main()
     test2<S, SV>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_swap/swap.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_swap/swap.pass.cpp
index 79adee48764e8d92db9d8169df5990b263781540..8fdf3fea9b4f2943c4d1f37e2ac14fc60b20ebad 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_swap/swap.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_swap/swap.pass.cpp
@@ -31,7 +31,7 @@ test(S s1, S s2)
     assert(s2 == s1_);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -73,4 +73,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), S("12345678901234567890"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/nothing_to_do.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string.io/get_line.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string.io/get_line.pass.cpp
index 9937863b28af1768b7780fe49efb66fd08f02376..8e663cb4f604445cf106f89b6afe78115fbef829 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string.io/get_line.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string.io/get_line.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::istringstream in(" abc\n  def\n   ghij");
@@ -77,4 +77,6 @@ int main()
         assert(s == L"   ghij");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string.io/get_line_delim.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string.io/get_line_delim.pass.cpp
index 965137c1d30813d7f4c1a9dffa389e5998749d18..b081b55c920ca8ad1aadebc59fcd897e9fc86647 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string.io/get_line_delim.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string.io/get_line_delim.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::istringstream in(" abc*  def**   ghij");
@@ -89,4 +89,6 @@ int main()
         assert(s == L"   ghij");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string.io/get_line_delim_rv.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string.io/get_line_delim_rv.pass.cpp
index b2255d068b2bebf60da3fdcb4cd016313846676f..b1511f21192d5bcd4b86d7422e32a9a793143661 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string.io/get_line_delim_rv.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string.io/get_line_delim_rv.pass.cpp
@@ -21,7 +21,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::string s("initial text");
@@ -45,4 +45,6 @@ int main()
         getline(std::wistringstream(L" abc*  def*   ghij"), s, L'*');
         assert(s == L" abc");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string.io/get_line_rv.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string.io/get_line_rv.pass.cpp
index a87529a0eab72f3dd5549110ad071e1b155bca54..cf4772c43d3552b16eebe603048e2324601ab037 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string.io/get_line_rv.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string.io/get_line_rv.pass.cpp
@@ -21,7 +21,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::string s("initial text");
@@ -45,4 +45,6 @@ int main()
         getline(std::wistringstream(L" abc\n  def\n   ghij"), s);
         assert(s == L" abc");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string.io/stream_extract.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string.io/stream_extract.pass.cpp
index 85f399dcd0da91d79e3ed3995311e339a726350e..389701d1d518733364c18321d2c9811f4204d872 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string.io/stream_extract.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string.io/stream_extract.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::istringstream in("a bc defghij");
@@ -113,4 +113,6 @@ int main()
         assert(in.fail());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string.io/stream_insert.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string.io/stream_insert.pass.cpp
index eb272c29bc63eaf2683f8486d4241d79622dbfba..b30fd5afaf5f99b29cb5445c25e35e3a4c7af6e4 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string.io/stream_insert.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string.io/stream_insert.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::ostringstream out;
@@ -87,4 +87,6 @@ int main()
         assert(L"   " + s == out.str());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string.special/swap.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string.special/swap.pass.cpp
index 944bd45539112ae0adda3578db62612f2294741d..f644f2870753d3fbbc58983b1df8650d9bfcb11a 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string.special/swap.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string.special/swap.pass.cpp
@@ -33,7 +33,7 @@ test(S s1, S s2)
     assert(s2 == s1_);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -75,4 +75,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), S("12345678901234567890"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string.special/swap_noexcept.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string.special/swap_noexcept.pass.cpp
index a00eb17be591ff7d234192044e6a9b983fb9d0b3..3f6ce447cf705f39d4a22e745a26d22eeefe0cd1 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string.special/swap_noexcept.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string.special/swap_noexcept.pass.cpp
@@ -53,7 +53,7 @@ struct some_alloc2
     typedef std::true_type is_always_equal;
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::string C;
@@ -81,4 +81,6 @@ int main()
         static_assert( noexcept(swap(std::declval<C&>(), std::declval<C&>())), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_op!=/pointer_string.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_op!=/pointer_string.pass.cpp
index 527d59d68878daf084cfe0d5b595cfb10e96ac61..bf2cc8413ab127e8143708e8fc7cce4b01bea459 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_op!=/pointer_string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_op!=/pointer_string.pass.cpp
@@ -23,7 +23,7 @@ test(const typename S::value_type* lhs, const S& rhs, bool x)
     assert((lhs != rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -65,4 +65,6 @@ int main()
     test("abcdefghijklmnopqrst", S("abcdefghijklmnopqrst"), false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_op!=/string_pointer.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_op!=/string_pointer.pass.cpp
index b1e6fa73d4f422a1f51f40aec75072bf56661b58..76e0abe23784c28624598d51c3e4252b2ec26a8b 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_op!=/string_pointer.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_op!=/string_pointer.pass.cpp
@@ -23,7 +23,7 @@ test(const S& lhs, const typename S::value_type* rhs, bool x)
     assert((lhs != rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -65,4 +65,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), "abcdefghijklmnopqrst", false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_op!=/string_string.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_op!=/string_string.pass.cpp
index 9825c1b38308b3f2031eba963e3d40a5347b4354..30aeb501a5927db2599c6ce5dacbce8ab9db9d7c 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_op!=/string_string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_op!=/string_string.pass.cpp
@@ -24,7 +24,7 @@ test(const S& lhs, const S& rhs, bool x)
     assert((lhs != rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -66,4 +66,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), S("abcdefghijklmnopqrst"), false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_op!=/string_string_view.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_op!=/string_string_view.pass.cpp
index 7108d819e0b5a8b8479a06d0d0d01d3d498b4dbc..5b01455e7f8bbff2ce98a5bb07ed3abd5b8b9c5d 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_op!=/string_string_view.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_op!=/string_string_view.pass.cpp
@@ -22,7 +22,7 @@ test(const S& lhs, SV rhs, bool x)
     assert((lhs != rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -66,4 +66,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), SV("abcdefghijklmnopqrst"), false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_op!=/string_view_string.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_op!=/string_view_string.pass.cpp
index 8f3906bf18bd82092dedc9cfb17e859f360c7099..2d6957e3494c3547921b093ccc38657795ca9e5f 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_op!=/string_view_string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_op!=/string_view_string.pass.cpp
@@ -22,7 +22,7 @@ test(SV lhs, const S& rhs, bool x)
     assert((lhs != rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -66,4 +66,6 @@ int main()
     test(SV("abcdefghijklmnopqrst"), S("abcdefghijklmnopqrst"), false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_op+/char_string.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_op+/char_string.pass.cpp
index c24d80768424dada90277a9a99e81c5d310ff613..9ab3c0611971db881894b9a985fad43a367894bb 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_op+/char_string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_op+/char_string.pass.cpp
@@ -35,7 +35,7 @@ void test1(typename S::value_type lhs, S&& rhs, const S& x) {
 }
 #endif
 
-int main() {
+int main(int, char**) {
   {
     typedef std::string S;
     test0('a', S(""), S("a"));
@@ -66,4 +66,6 @@ int main() {
     test1('a', S("12345678901234567890"), S("a12345678901234567890"));
   }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_op+/pointer_string.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_op+/pointer_string.pass.cpp
index 654eca290f5b0319ab8c434508ca9ecefa9782ea..cf13fbb51d6e1778ec2fdaa556066561bc3388c8 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_op+/pointer_string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_op+/pointer_string.pass.cpp
@@ -35,7 +35,7 @@ void test1(const typename S::value_type* lhs, S&& rhs, const S& x) {
 }
 #endif
 
-int main() {
+int main(int, char**) {
   {
     typedef std::string S;
     test0("", S(""), S(""));
@@ -127,4 +127,6 @@ int main() {
           S("abcdefghijklmnopqrst12345678901234567890"));
   }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_op+/string_char.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_op+/string_char.pass.cpp
index 5196aba1a693a15fbd022f9687d365c8d98f7213..32411144db276ef8601c970a6e731fd6b1dc77d6 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_op+/string_char.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_op+/string_char.pass.cpp
@@ -35,7 +35,7 @@ void test1(S&& lhs, typename S::value_type rhs, const S& x) {
 }
 #endif
 
-int main() {
+int main(int, char**) {
   {
     typedef std::string S;
     test0(S(""), '1', S("1"));
@@ -66,4 +66,6 @@ int main() {
     test1(S("abcdefghijklmnopqrst"), '1', S("abcdefghijklmnopqrst1"));
   }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_op+/string_pointer.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_op+/string_pointer.pass.cpp
index ef8b8001009eb849372af1842a60eaab4705b421..4fec8482966233cf364b7a9c088df091e3cd7f7b 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_op+/string_pointer.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_op+/string_pointer.pass.cpp
@@ -35,7 +35,7 @@ void test1(S&& lhs, const typename S::value_type* rhs, const S& x) {
 }
 #endif
 
-int main() {
+int main(int, char**) {
   {
     typedef std::string S;
     test0(S(""), "", S(""));
@@ -126,4 +126,6 @@ int main() {
           S("abcdefghijklmnopqrst12345678901234567890"));
   }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_op+/string_string.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_op+/string_string.pass.cpp
index 2bc38c71a00bf5516d5d655acfffa4ef64483efd..00aaf5cc0921703a9a59dad6a8187b817c5ae071 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_op+/string_string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_op+/string_string.pass.cpp
@@ -58,7 +58,7 @@ void test3(S&& lhs, S&& rhs, const S& x) {
 
 #endif
 
-int main() {
+int main(int, char**) {
   {
     typedef std::string S;
     test0(S(""), S(""), S(""));
@@ -245,4 +245,6 @@ int main() {
           S("abcdefghijklmnopqrst12345678901234567890"));
   }
 #endif // TEST_STD_VER >= 11
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_operator==/pointer_string.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_operator==/pointer_string.pass.cpp
index 11ad5f151940ff031e61d2cc38d9ab548e7130f0..5db04b3a8d67998aeeff55817bbb0d6975ff817f 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_operator==/pointer_string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_operator==/pointer_string.pass.cpp
@@ -23,7 +23,7 @@ test(const typename S::value_type* lhs, const S& rhs, bool x)
     assert((lhs == rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -65,4 +65,6 @@ int main()
     test("abcdefghijklmnopqrst", S("abcdefghijklmnopqrst"), true);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_operator==/string_pointer.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_operator==/string_pointer.pass.cpp
index f020c2234f3a824e8820c44160dfa339cd1f6616..aa79e17d121933e15ab37a31519bbc5ae209e523 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_operator==/string_pointer.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_operator==/string_pointer.pass.cpp
@@ -23,7 +23,7 @@ test(const S& lhs, const typename S::value_type* rhs, bool x)
     assert((lhs == rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -65,4 +65,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), "abcdefghijklmnopqrst", true);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_operator==/string_string.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_operator==/string_string.pass.cpp
index 39ec5cc06e4d58ea46ad46a342ae752d1b11515f..357a91fd9f5955f15dd3f9860844106723844020 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_operator==/string_string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_operator==/string_string.pass.cpp
@@ -24,7 +24,7 @@ test(const S& lhs, const S& rhs, bool x)
     assert((lhs == rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -66,4 +66,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), S("abcdefghijklmnopqrst"), true);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_operator==/string_string_view.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_operator==/string_string_view.pass.cpp
index f4791e3b54c7c305d4f55a3a073bca594827b0e0..06c16d07079123572ef6f8a23528839ed40f491d 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_operator==/string_string_view.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_operator==/string_string_view.pass.cpp
@@ -22,7 +22,7 @@ test(const S& lhs, SV rhs, bool x)
     assert((lhs == rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -66,4 +66,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), SV("abcdefghijklmnopqrst"), true);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_operator==/string_view_string.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_operator==/string_view_string.pass.cpp
index fdf89a2c9c4f9601415cb6969eedec8bc93345f5..7ebdc0934930ec253b2bd45684e309a468c8c7a6 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_operator==/string_view_string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_operator==/string_view_string.pass.cpp
@@ -22,7 +22,7 @@ test(SV lhs, const S& rhs, bool x)
     assert((lhs == rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -66,4 +66,6 @@ int main()
     test(SV("abcdefghijklmnopqrst"), S("abcdefghijklmnopqrst"), true);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt/pointer_string.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt/pointer_string.pass.cpp
index dd27087b66c4883ffa039d0ce516685483ec0abb..db28cd4d1b464ada8d4b0d8c5c687f910c4e068f 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt/pointer_string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt/pointer_string.pass.cpp
@@ -23,7 +23,7 @@ test(const typename S::value_type* lhs, const S& rhs, bool x)
     assert((lhs > rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -65,4 +65,6 @@ int main()
     test("abcdefghijklmnopqrst", S("abcdefghijklmnopqrst"), false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt/string_pointer.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt/string_pointer.pass.cpp
index 4109eab333643930c1eec32278132bf9aea12a23..56521e91662be5eed57760793ee45245e6b49deb 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt/string_pointer.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt/string_pointer.pass.cpp
@@ -23,7 +23,7 @@ test(const S& lhs, const typename S::value_type* rhs, bool x)
     assert((lhs > rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -65,4 +65,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), "abcdefghijklmnopqrst", false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt/string_string.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt/string_string.pass.cpp
index 3514ffc11bc4337487d7e64e694ff68644d7b8f0..0cfafb80911ebf66105bbf79e8940ba252a19625 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt/string_string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt/string_string.pass.cpp
@@ -24,7 +24,7 @@ test(const S& lhs, const S& rhs, bool x)
     assert((lhs > rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -66,4 +66,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), S("abcdefghijklmnopqrst"), false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt/string_string_view.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt/string_string_view.pass.cpp
index 8ad82bf01f20cd5650759455e948885cf6da5211..692fbd4fe816819d5a96808a0580c55f97b8cb40 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt/string_string_view.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt/string_string_view.pass.cpp
@@ -22,7 +22,7 @@ test(const S& lhs, SV rhs, bool x)
     assert((lhs > rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -66,4 +66,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), SV("abcdefghijklmnopqrst"), false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt/string_view_string.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt/string_view_string.pass.cpp
index af98fa15363856b7fb746bbeda27a8ddbf0f4829..f6a2fa55588f3edff9270e2a2cc39b9f595225ce 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt/string_view_string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt/string_view_string.pass.cpp
@@ -22,7 +22,7 @@ test(SV lhs, const S& rhs, bool x)
     assert((lhs > rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -66,4 +66,6 @@ int main()
     test(SV("abcdefghijklmnopqrst"), S("abcdefghijklmnopqrst"), false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt=/pointer_string.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt=/pointer_string.pass.cpp
index 0d7e5acea1c90f095a4a854ff10d7f761d7d69ba..e868531a6833a39b46baa69784653d4871f3a59e 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt=/pointer_string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt=/pointer_string.pass.cpp
@@ -23,7 +23,7 @@ test(const typename S::value_type* lhs, const S& rhs, bool x)
     assert((lhs >= rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -65,4 +65,6 @@ int main()
     test("abcdefghijklmnopqrst", S("abcdefghijklmnopqrst"), true);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt=/string_pointer.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt=/string_pointer.pass.cpp
index 93b9d2a874d52a3aec30c8ef43bec46e51cd1826..8aad50782472cdd7fdde438f7701f267287bae53 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt=/string_pointer.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt=/string_pointer.pass.cpp
@@ -23,7 +23,7 @@ test(const S& lhs, const typename S::value_type* rhs, bool x)
     assert((lhs >= rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -65,4 +65,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), "abcdefghijklmnopqrst", true);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt=/string_string.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt=/string_string.pass.cpp
index 06f23205904e7abecd500e0b9d1cf8bd35650df3..f0ab16cbb62af3bfc57b1cfe136e0a7b8106342d 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt=/string_string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt=/string_string.pass.cpp
@@ -24,7 +24,7 @@ test(const S& lhs, const S& rhs, bool x)
     assert((lhs >= rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -66,4 +66,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), S("abcdefghijklmnopqrst"), true);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt=/string_string_view.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt=/string_string_view.pass.cpp
index 27c2b35d3553bff5be09802bbf75510eee62cc16..c7eb3e3e45ec93e9f81fed2238ddece79a6020ef 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt=/string_string_view.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt=/string_string_view.pass.cpp
@@ -22,7 +22,7 @@ test(const S& lhs, SV rhs, bool x)
     assert((lhs >= rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -66,4 +66,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), SV("abcdefghijklmnopqrst"), true);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt=/string_view_string.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt=/string_view_string.pass.cpp
index ff4a35b39bf2f38c64cee13bb221e1c6271ab8e3..b49c1348a99095e6fd96745bf68f8fb3ddd8acad 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt=/string_view_string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_opgt=/string_view_string.pass.cpp
@@ -22,7 +22,7 @@ test(SV lhs, const S& rhs, bool x)
     assert((lhs >= rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -66,4 +66,6 @@ int main()
     test(SV("abcdefghijklmnopqrst"), S("abcdefghijklmnopqrst"), true);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt/pointer_string.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt/pointer_string.pass.cpp
index 0c3943d7db2fc7495656e6de45e06b1fbcfe82c2..1609c4d87d997f66b88af106abb1af3a0fa5ac23 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt/pointer_string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt/pointer_string.pass.cpp
@@ -23,7 +23,7 @@ test(const typename S::value_type* lhs, const S& rhs, bool x)
     assert((lhs < rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -65,4 +65,6 @@ int main()
     test("abcdefghijklmnopqrst", S("abcdefghijklmnopqrst"), false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt/string_pointer.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt/string_pointer.pass.cpp
index d91c3b1aeef3984c7f4cdcf1128c814d5062f47e..079344bb8295d90135f7b5ff80b3a74caf86e569 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt/string_pointer.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt/string_pointer.pass.cpp
@@ -23,7 +23,7 @@ test(const S& lhs, const typename S::value_type* rhs, bool x)
     assert((lhs < rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -65,4 +65,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), "abcdefghijklmnopqrst", false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt/string_string.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt/string_string.pass.cpp
index 0b05b6c359298abd168d35d3e1113322670e8b8c..586faa40f0734305d21736a887313dede13ce1c3 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt/string_string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt/string_string.pass.cpp
@@ -24,7 +24,7 @@ test(const S& lhs, const S& rhs, bool x)
     assert((lhs < rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -66,4 +66,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), S("abcdefghijklmnopqrst"), false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt/string_string_view.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt/string_string_view.pass.cpp
index eec351c24ec7717624e6be21527e96d333775797..79393def5ddde70c4ffc3d5427cdaa4b42e135e1 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt/string_string_view.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt/string_string_view.pass.cpp
@@ -22,7 +22,7 @@ test(const S& lhs, SV rhs, bool x)
     assert((lhs < rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -66,4 +66,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), SV("abcdefghijklmnopqrst"), false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt/string_view_string.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt/string_view_string.pass.cpp
index 9b2b7ddd9a31c827c36e36f70b340c3b9955a9d1..7e8b139c332a34fe117f904bec191c84390b195e 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt/string_view_string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt/string_view_string.pass.cpp
@@ -22,7 +22,7 @@ test(SV lhs, const S& rhs, bool x)
     assert((lhs < rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -66,4 +66,6 @@ int main()
     test(SV("abcdefghijklmnopqrst"), S("abcdefghijklmnopqrst"), false);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt=/pointer_string.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt=/pointer_string.pass.cpp
index 5354e6b75c467ba4da05a1931e3cf3072167b617..cae9233dfb26173eaf37092b5ee8025e71387cd7 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt=/pointer_string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt=/pointer_string.pass.cpp
@@ -23,7 +23,7 @@ test(const typename S::value_type* lhs, const S& rhs, bool x)
     assert((lhs <= rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -65,4 +65,6 @@ int main()
     test("abcdefghijklmnopqrst", S("abcdefghijklmnopqrst"), true);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt=/string_pointer.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt=/string_pointer.pass.cpp
index 5fe8948dd61e63f8b0213fb8608b3a397f9bbdbd..07f9b355185e573af6d8c07a5fa69ebc43769bb6 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt=/string_pointer.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt=/string_pointer.pass.cpp
@@ -23,7 +23,7 @@ test(const S& lhs, const typename S::value_type* rhs, bool x)
     assert((lhs <= rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -65,4 +65,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), "abcdefghijklmnopqrst", true);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt=/string_string.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt=/string_string.pass.cpp
index 1261f518541e94957dd7f3d7ad6b28aee7660069..8d40f2f0a5b1f4ea26a1e4e3ad4817abab203572 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt=/string_string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt=/string_string.pass.cpp
@@ -24,7 +24,7 @@ test(const S& lhs, const S& rhs, bool x)
     assert((lhs <= rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -66,4 +66,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), S("abcdefghijklmnopqrst"), true);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt=/string_string_view.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt=/string_string_view.pass.cpp
index bdaa49a63a1c2929ca9b27a14fc4e6b532799994..3df9e39cc0da67ba580ec55f9e8fc69eee370cbd 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt=/string_string_view.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt=/string_string_view.pass.cpp
@@ -22,7 +22,7 @@ test(const S& lhs, SV rhs, bool x)
     assert((lhs <= rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -66,4 +66,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), SV("abcdefghijklmnopqrst"), true);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt=/string_view_string.pass.cpp b/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt=/string_view_string.pass.cpp
index 64d286cd8906f563ba7bae5dabc818e6306df218..cb7b1a4c451b73422935afa279ce9dac6ee85894 100644
--- a/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt=/string_view_string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.nonmembers/string_oplt=/string_view_string.pass.cpp
@@ -22,7 +22,7 @@ test(SV lhs, const S& rhs, bool x)
     assert((lhs <= rhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -66,4 +66,6 @@ int main()
     test(SV("abcdefghijklmnopqrst"), S("abcdefghijklmnopqrst"), true);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/nothing_to_do.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string.accessors/c_str.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string.accessors/c_str.pass.cpp
index 7c713e4b0b3c96f758963a8771b5e5b7afb5cba3..2677230c2d528990d35371e86abb0b50a2ce5fbe 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string.accessors/c_str.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string.accessors/c_str.pass.cpp
@@ -30,7 +30,7 @@ test(const S& s)
         assert(T::eq(str[0], typename S::value_type()));
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -48,4 +48,6 @@ int main()
     test(S("abcdefghijklmnopqrst"));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string.accessors/data.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string.accessors/data.pass.cpp
index 9c643a1723682c9ffe32123c6fe72810d2f61afd..6aa07302a951d6ba27fed0dab04b0a9f9a98fec8 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string.accessors/data.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string.accessors/data.pass.cpp
@@ -47,7 +47,7 @@ test_nonconst(S& s)
         assert(T::eq(str[0], typename S::value_type()));
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -74,4 +74,6 @@ int main()
     S s4("abcdefghijklmnopqrst"); test_nonconst(s4);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string.accessors/get_allocator.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string.accessors/get_allocator.pass.cpp
index 6261ad55f1a9481ac7365bd2866109fac4e76acc..7edf5a88d9db1356acd7435e87b2f6eb727a871f 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string.accessors/get_allocator.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string.accessors/get_allocator.pass.cpp
@@ -23,7 +23,7 @@ test(const S& s, const typename S::allocator_type& a)
     assert(s.get_allocator() == a);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef test_allocator<char> A;
@@ -43,4 +43,6 @@ int main()
     test(S("abcdefghijklmnopqrst", A()), A());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_compare/pointer.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_compare/pointer.pass.cpp
index 6219d6babfc4da0905e6d7e17b2bbb316ef20a2b..0af8ce02f953431d176d9017d6d776e714df8eec 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_compare/pointer.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_compare/pointer.pass.cpp
@@ -31,7 +31,7 @@ test(const S& s, const typename S::value_type* str, int x)
     assert(sign(s.compare(str)) == sign(x));
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -73,4 +73,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), "abcdefghijklmnopqrst", 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_compare/size_size_T_size_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_compare/size_size_T_size_size.pass.cpp
index ad781f23c26dd64ec47549484dc45c1a697addd1..abab9879a14eaa0d6c8af232f552365d5ee3ff18 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_compare/size_size_T_size_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_compare/size_size_T_size_size.pass.cpp
@@ -5840,7 +5840,7 @@ void test55()
     test_npos(S("abcde"), 0, 0, SV("abcdefghij"), 5, -5);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -5989,4 +5989,6 @@ int main()
 //  calls compare(size, size, string(arr), 0, npos)
     assert(s.compare(0, 4, arr, 0, std::string::npos) == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_compare/size_size_pointer.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_compare/size_size_pointer.pass.cpp
index aa44e16a9c388063bc9870dedafc8158be96ee92..4e77fc09c8e41bbf40b1d995ac9182da4eb3cd28 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_compare/size_size_pointer.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_compare/size_size_pointer.pass.cpp
@@ -361,7 +361,7 @@ void test2()
     test(S("abcdefghijklmnopqrst"), 21, 0, "abcdefghijklmnopqrst", 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -377,4 +377,6 @@ int main()
     test2<S>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_compare/size_size_pointer_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_compare/size_size_pointer_size.pass.cpp
index f9c0244ec3f115d978e0ea20d95170c778518e9f..75efbadcc811541340573c16ee8579996fd4899b 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_compare/size_size_pointer_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_compare/size_size_pointer_size.pass.cpp
@@ -1294,7 +1294,7 @@ void test11()
     test(S("abcdefghijklmnopqrst"), 21, 0, "abcdefghijklmnopqrst", 20, 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -1328,4 +1328,6 @@ int main()
     test11<S>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_compare/size_size_string.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_compare/size_size_string.pass.cpp
index 06b5e531018bd9ebe82e35857c80df78e62f97d8..55fd823718eec9b8f5dfc53de535a74051b9809f 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_compare/size_size_string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_compare/size_size_string.pass.cpp
@@ -360,7 +360,7 @@ void test2()
     test(S("abcdefghijklmnopqrst"), 21, 0, S("abcdefghijklmnopqrst"), 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -383,4 +383,6 @@ int main()
     assert(s.compare(0, 1, {"abc", 1}) < 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_compare/size_size_string_size_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_compare/size_size_string_size_size.pass.cpp
index 6a231a867c35e7241355bf8146347f2c542cb117..05ba6ac82c5558cdc599a45b3c4c62954f16404e 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_compare/size_size_string_size_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_compare/size_size_string_size_size.pass.cpp
@@ -5836,7 +5836,7 @@ void test55()
     test_npos(S("abcde"), 0, 0, S("abcdefghij"), 5, -5);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -5958,4 +5958,6 @@ int main()
     test55<S>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_compare/size_size_string_view.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_compare/size_size_string_view.pass.cpp
index 00245e834d72c18b13e12eefce61affca9bee87c..94c73ab31a62cc506da88b02c8e0d50085bf2986 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_compare/size_size_string_view.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_compare/size_size_string_view.pass.cpp
@@ -361,7 +361,7 @@ void test2()
     test(S("abcdefghijklmnopqrst"), 21, 0, SV("abcdefghijklmnopqrst"), 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -379,4 +379,6 @@ int main()
     test2<S, SV>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_compare/string.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_compare/string.pass.cpp
index 7c3bdb1595ee2518dcb754cfec5f907a59a2ddf2..279ae3075846c07a549ba9ee3e285bb7cbde17e8 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_compare/string.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_compare/string.pass.cpp
@@ -32,7 +32,7 @@ test(const S& s, const S& str, int x)
     assert(sign(s.compare(str)) == sign(x));
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -81,4 +81,6 @@ int main()
     assert(s.compare({"abc", 1}) < 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_compare/string_view.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_compare/string_view.pass.cpp
index 3e123ad7acebf0c6d9a86528af5f135a4d72650d..2abc7fc1ac1898605f5468051b4cdcf878b5ef17 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_compare/string_view.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_compare/string_view.pass.cpp
@@ -31,7 +31,7 @@ test(const S& s, SV sv, int x)
     assert(sign(s.compare(sv)) == sign(x));
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -75,4 +75,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), SV("abcdefghijklmnopqrst"), 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_find.first.not.of/char_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_find.first.not.of/char_size.pass.cpp
index 2c4994670c86bdb1cfbd3c4bdcfddcfd7f14e5a3..7bada8446ffa2d5c0c9491e392dce157f4303e27 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_find.first.not.of/char_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_find.first.not.of/char_size.pass.cpp
@@ -34,7 +34,7 @@ test(const S& s, typename S::value_type c, typename S::size_type x)
         assert(x < s.size());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -98,4 +98,6 @@ int main()
     test(S("laenfsbridchgotmkqpj"), 'q', 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_find.first.not.of/pointer_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_find.first.not.of/pointer_size.pass.cpp
index cb6fc1e97288e93bf5310d5e6f522ae70255ab80..bd20ea1bb4a1d9f55060c9cea705189210721273 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_find.first.not.of/pointer_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_find.first.not.of/pointer_size.pass.cpp
@@ -140,7 +140,7 @@ void test1()
     test(S("pniotcfrhqsmgdkjbael"), "htaobedqikfplcgjsmrn", S::npos);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -154,4 +154,6 @@ int main()
     test1<S>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_find.first.not.of/pointer_size_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_find.first.not.of/pointer_size_size.pass.cpp
index 708a04352f98dc42bf8eb8f65fcf68fcb365a5e5..46c5511d9aefaf2de9da499cd30578163b983102 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_find.first.not.of/pointer_size_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_find.first.not.of/pointer_size_size.pass.cpp
@@ -365,7 +365,7 @@ void test3()
     test(S("hnbrcplsjfgiktoedmaq"), "qprlsfojamgndekthibc", 21, 20, S::npos);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -383,4 +383,6 @@ int main()
     test3<S>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_find.first.not.of/string_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_find.first.not.of/string_size.pass.cpp
index 1ea41354f28acf438f7bb85a7864fc8903536031..7f12ab1ba27ce86f477662e710ced0d0ec1fc11b 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_find.first.not.of/string_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_find.first.not.of/string_size.pass.cpp
@@ -140,7 +140,7 @@ void test1()
     test(S("pniotcfrhqsmgdkjbael"), S("htaobedqikfplcgjsmrn"), S::npos);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -161,4 +161,6 @@ int main()
     assert(s.find_first_not_of({"abc", 1}) == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_find.first.not.of/string_view_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_find.first.not.of/string_view_size.pass.cpp
index 3cb3e74204d774246a2506558221b4661ff002a2..54ce737ecc6086c670de784ebc527c6483fa8b42 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_find.first.not.of/string_view_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_find.first.not.of/string_view_size.pass.cpp
@@ -139,7 +139,7 @@ void test1()
     test(S("pniotcfrhqsmgdkjbael"), SV("htaobedqikfplcgjsmrn"), S::npos);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -155,4 +155,6 @@ int main()
     test1<S, SV>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_find.first.of/char_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_find.first.of/char_size.pass.cpp
index cf8548744f8bc8f3ae5a1f0b16d112906ce6e622..da630f07e762f27ea3205d1beff8e2587d6f0a64 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_find.first.of/char_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_find.first.of/char_size.pass.cpp
@@ -34,7 +34,7 @@ test(const S& s, typename S::value_type c, typename S::size_type x)
         assert(x < s.size());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -94,4 +94,6 @@ int main()
     test(S("laenfsbridchgotmkqpj"), 'e', 2);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_find.first.of/pointer_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_find.first.of/pointer_size.pass.cpp
index 4c435537c464dc1e69b73fcc0aea15a7a3f5bd8a..2162ea14cf1f835ec7211dbc629744dbb4036b36 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_find.first.of/pointer_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_find.first.of/pointer_size.pass.cpp
@@ -140,7 +140,7 @@ void test1()
     test(S("pniotcfrhqsmgdkjbael"), "htaobedqikfplcgjsmrn", 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -154,4 +154,6 @@ int main()
     test1<S>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_find.first.of/pointer_size_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_find.first.of/pointer_size_size.pass.cpp
index c8b62b1f454923059fde954131898a302c17539a..e0bb0f2fb777dc0e93dac5aa0868d56443347ea8 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_find.first.of/pointer_size_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_find.first.of/pointer_size_size.pass.cpp
@@ -365,7 +365,7 @@ void test3()
     test(S("hnbrcplsjfgiktoedmaq"), "qprlsfojamgndekthibc", 21, 20, S::npos);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -383,4 +383,6 @@ int main()
     test3<S>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_find.first.of/string_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_find.first.of/string_size.pass.cpp
index fc79c89d151c0ff9fec73e7065b33f774dbb12b4..1ae2123c3eb47b66db5d432084d98b0e0c8b7578 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_find.first.of/string_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_find.first.of/string_size.pass.cpp
@@ -140,7 +140,7 @@ void test1()
     test(S("pniotcfrhqsmgdkjbael"), S("htaobedqikfplcgjsmrn"), 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -161,4 +161,6 @@ int main()
     assert(s.find_first_of({"abc", 1}) == std::string::npos);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_find.first.of/string_view_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_find.first.of/string_view_size.pass.cpp
index ae29e47481bedb6c0b8b0954cbb86cbcf1ac0fb1..8cd272408a02c6a2f6a16fb5967b98c7b10ab5c9 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_find.first.of/string_view_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_find.first.of/string_view_size.pass.cpp
@@ -139,7 +139,7 @@ void test1()
     test(S("pniotcfrhqsmgdkjbael"), SV("htaobedqikfplcgjsmrn"), 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -155,4 +155,6 @@ int main()
     test1<S, SV>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_find.last.not.of/char_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_find.last.not.of/char_size.pass.cpp
index 6276c491075603a39fcbe4c610518705e6d22560..fd77eb89d86feb43d4921a4722922c5014b6376a 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_find.last.not.of/char_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_find.last.not.of/char_size.pass.cpp
@@ -34,7 +34,7 @@ test(const S& s, typename S::value_type c, typename S::size_type x)
         assert(x < s.size());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -94,4 +94,6 @@ int main()
     test(S("laenfsbridchgotmkqpj"), 'i', 19);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_find.last.not.of/pointer_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_find.last.not.of/pointer_size.pass.cpp
index 5cc9c0bf40ab34276581f701d532d9e3820c848c..1234ccb4de2050368fb99ddba62dd02755c7e128 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_find.last.not.of/pointer_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_find.last.not.of/pointer_size.pass.cpp
@@ -140,7 +140,7 @@ void test1()
     test(S("pniotcfrhqsmgdkjbael"), "htaobedqikfplcgjsmrn", S::npos);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -154,4 +154,6 @@ int main()
     test1<S>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_find.last.not.of/pointer_size_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_find.last.not.of/pointer_size_size.pass.cpp
index 76834c2e81dc52a9f4babd747d886e5f2a302ab3..4c07f4d6129ba1d92bb7802c865158b3899da202 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_find.last.not.of/pointer_size_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_find.last.not.of/pointer_size_size.pass.cpp
@@ -365,7 +365,7 @@ void test3()
     test(S("hnbrcplsjfgiktoedmaq"), "qprlsfojamgndekthibc", 21, 20, S::npos);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -383,4 +383,6 @@ int main()
     test3<S>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_find.last.not.of/string_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_find.last.not.of/string_size.pass.cpp
index 254e639dcfbdffa3ab3b610c87b9b8ffdb70772d..8232612c1e70768ff81f5f02ea94cbc9b6286a5d 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_find.last.not.of/string_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_find.last.not.of/string_size.pass.cpp
@@ -140,7 +140,7 @@ void test1()
     test(S("pniotcfrhqsmgdkjbael"), S("htaobedqikfplcgjsmrn"), S::npos);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -161,4 +161,6 @@ int main()
     assert(s.find_last_not_of({"abc", 1}) == s.size() - 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_find.last.not.of/string_view_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_find.last.not.of/string_view_size.pass.cpp
index 421ec966db27e78980b4a99cb39203c89852ee7d..da5054b7df6582b0d2e850d969447aa1dd5783ba 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_find.last.not.of/string_view_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_find.last.not.of/string_view_size.pass.cpp
@@ -139,7 +139,7 @@ void test1()
     test(S("pniotcfrhqsmgdkjbael"), SV("htaobedqikfplcgjsmrn"), S::npos);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -155,4 +155,6 @@ int main()
 //     test1<S, SV>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_find.last.of/char_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_find.last.of/char_size.pass.cpp
index 2c5359e5edfa4bd9f29d7c4537eeb2338eb9ea22..4292b1eb8bff91915e5267358ec303c7f61e45bd 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_find.last.of/char_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_find.last.of/char_size.pass.cpp
@@ -34,7 +34,7 @@ test(const S& s, typename S::value_type c, typename S::size_type x)
         assert(x < s.size());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -94,4 +94,6 @@ int main()
     test(S("laenfsbridchgotmkqpj"), 'm', 15);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_find.last.of/pointer_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_find.last.of/pointer_size.pass.cpp
index 6a320788d4bc879e3350623256c7994e9c02b9a9..0b86a10c5122dfb63bebbf7cfa2d97e5e67b6328 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_find.last.of/pointer_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_find.last.of/pointer_size.pass.cpp
@@ -140,7 +140,7 @@ void test1()
     test(S("pniotcfrhqsmgdkjbael"), "htaobedqikfplcgjsmrn", 19);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -154,4 +154,6 @@ int main()
     test1<S>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_find.last.of/pointer_size_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_find.last.of/pointer_size_size.pass.cpp
index 46d61a44aec051f25f4c1c262c5c68a55bd96f56..9c5f670a9c723b6d553aeba127bcb03365978afa 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_find.last.of/pointer_size_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_find.last.of/pointer_size_size.pass.cpp
@@ -365,7 +365,7 @@ void test3()
     test(S("hnbrcplsjfgiktoedmaq"), "qprlsfojamgndekthibc", 21, 20, 19);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -383,4 +383,6 @@ int main()
     test3<S>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_find.last.of/string_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_find.last.of/string_size.pass.cpp
index c5f1a3a7d96231b8af039ec8e6c1ac619790c01c..f3ddb468d4988219bdab4d660bcd82cda05c4c36 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_find.last.of/string_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_find.last.of/string_size.pass.cpp
@@ -140,7 +140,7 @@ void test1()
     test(S("pniotcfrhqsmgdkjbael"), S("htaobedqikfplcgjsmrn"), 19);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -161,4 +161,6 @@ int main()
     assert(s.find_last_of({"abc", 1}) == std::string::npos);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_find.last.of/string_view_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_find.last.of/string_view_size.pass.cpp
index f98d66eec45aed16d93bd7abfbb0e3c5a1ddc235..ccf181faa55599413d8267a64153abf5868cc313 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_find.last.of/string_view_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_find.last.of/string_view_size.pass.cpp
@@ -139,7 +139,7 @@ void test1()
     test(S("pniotcfrhqsmgdkjbael"), SV("htaobedqikfplcgjsmrn"), 19);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -155,4 +155,6 @@ int main()
     test1<S, SV>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_find/char_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_find/char_size.pass.cpp
index c346a0196f38a48a6d84c884a4fbf8ee0f7e4e7d..5700d09575fbbe234799022cf0e4e5c5de7a638d 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_find/char_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_find/char_size.pass.cpp
@@ -34,7 +34,7 @@ test(const S& s, typename S::value_type c, typename S::size_type x)
         assert(0 <= x && x + 1 <= s.size());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -94,4 +94,6 @@ int main()
     test(S("abcdeabcdeabcdeabcde"), 'c', 2);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_find/pointer_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_find/pointer_size.pass.cpp
index a6136d3f844291ae3e8498bafcd3045d60599909..6e7ae3d41f4b5c0dc32521b594598fbadeda5a9c 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_find/pointer_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_find/pointer_size.pass.cpp
@@ -146,7 +146,7 @@ void test1()
     test(S("abcdeabcdeabcdeabcde"), "abcdeabcdeabcdeabcde", 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -160,4 +160,6 @@ int main()
     test1<S>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_find/pointer_size_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_find/pointer_size_size.pass.cpp
index 176ffbb563a89d71b8b3452af57eeffb00d69bb4..fad7507173da2ae70aef9fc53c076287e6d146ec 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_find/pointer_size_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_find/pointer_size_size.pass.cpp
@@ -365,7 +365,7 @@ void test3()
     test(S("abcdeabcdeabcdeabcde"), "abcdeabcdeabcdeabcde", 21, 20, S::npos);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -383,4 +383,6 @@ int main()
     test3<S>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_find/string_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_find/string_size.pass.cpp
index 482648ab3b049a9734f7173e973d14df668ab118..e8a91dd1f67b156be1c874025576690610d22a39 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_find/string_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_find/string_size.pass.cpp
@@ -140,7 +140,7 @@ void test1()
     test(S("abcdeabcdeabcdeabcde"), S("abcdeabcdeabcdeabcde"), 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -161,4 +161,6 @@ int main()
     assert(s.find({"abc", 1}) == std::string::npos);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_find/string_view_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_find/string_view_size.pass.cpp
index d84a41e4ca8657c15fb1beed1443cd56c30b3682..c1e78af10250add4f062f546ea16ba43f3c230cc 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_find/string_view_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_find/string_view_size.pass.cpp
@@ -139,7 +139,7 @@ void test1()
     test(S("abcdeabcdeabcdeabcde"), SV("abcdeabcdeabcdeabcde"), 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -155,4 +155,6 @@ int main()
     test1<S, SV>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_rfind/char_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_rfind/char_size.pass.cpp
index 9a30a63d172e4a27d0e96315a762e9c0b411a373..46ced312391886d851595f6883982a2dd5c29c8a 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_rfind/char_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_rfind/char_size.pass.cpp
@@ -34,7 +34,7 @@ test(const S& s, typename S::value_type c, typename S::size_type x)
         assert(x + 1 <= s.size());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -94,4 +94,6 @@ int main()
     test(S("abcdeabcdeabcdeabcde"), 'b', 16);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_rfind/pointer_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_rfind/pointer_size.pass.cpp
index 57a4d06bd134aef82b2d09e3ac6ab9adf333f332..715b5e57855661c73ae7e41011d00e6e1000d07b 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_rfind/pointer_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_rfind/pointer_size.pass.cpp
@@ -147,7 +147,7 @@ void test1()
     test(S("abcdeabcdeabcdeabcde"), "abcdeabcdeabcdeabcde", 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -161,4 +161,6 @@ int main()
     test1<S>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_rfind/pointer_size_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_rfind/pointer_size_size.pass.cpp
index 786affd27bca9047df51a7ec6b51b5f40f401248..e96700952277fefa0aedd817517c5d4ac5b70e03 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_rfind/pointer_size_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_rfind/pointer_size_size.pass.cpp
@@ -365,7 +365,7 @@ void test3()
     test(S("abcdeabcdeabcdeabcde"), "abcdeabcdeabcdeabcde", 21, 20, 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -383,4 +383,6 @@ int main()
     test3<S>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_rfind/string_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_rfind/string_size.pass.cpp
index c83acbf4d5d2f121daf26a31a65881ad7a51ee60..74cfb02ee28c782389fc6b2fc35574900e2be9f8 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_rfind/string_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_rfind/string_size.pass.cpp
@@ -140,7 +140,7 @@ void test1()
     test(S("abcdeabcdeabcdeabcde"), S("abcdeabcdeabcdeabcde"), 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -161,4 +161,6 @@ int main()
     assert(s.rfind({"abc", 1}) == std::string::npos);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_rfind/string_view_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_rfind/string_view_size.pass.cpp
index 3657e028c2e62f0b13b0d80c879217d49034901d..ea4f9c20597098b7fb50f5dcbc8efb14a187a9e2 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_rfind/string_view_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_rfind/string_view_size.pass.cpp
@@ -139,7 +139,7 @@ void test1()
     test(S("abcdeabcdeabcdeabcde"), SV("abcdeabcdeabcdeabcde"), 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -155,4 +155,6 @@ int main()
     test1<S, SV>();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.ops/string_substr/substr.pass.cpp b/libcxx/test/std/strings/basic.string/string.ops/string_substr/substr.pass.cpp
index 767dc506339b162fb9b8f75e9d6383c860554fe5..27af66e0670b6813f5851d92f6258c9cddcb2335 100644
--- a/libcxx/test/std/strings/basic.string/string.ops/string_substr/substr.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.ops/string_substr/substr.pass.cpp
@@ -47,7 +47,7 @@ test(const S& s, typename S::size_type pos, typename S::size_type n)
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -173,4 +173,6 @@ int main()
     test(S("dplqartnfgejichmoskb"), 21, 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.require/contiguous.pass.cpp b/libcxx/test/std/strings/basic.string/string.require/contiguous.pass.cpp
index fb2e3e6ce6bbb8e31e39a7d403ff7c10dd870f25..be090c90e1772bf1515708f9d14bd277be058f3d 100644
--- a/libcxx/test/std/strings/basic.string/string.require/contiguous.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.require/contiguous.pass.cpp
@@ -24,7 +24,7 @@ void test_contiguous ( const C &c )
         assert ( *(c.begin() + static_cast<typename C::difference_type>(i)) == *(std::addressof(*c.begin()) + i));
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -49,4 +49,6 @@ int main()
     test_contiguous(S("1234567890123456789012345678901234567890123456789012345678901234567890", A()));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.starts_with/starts_with.char.pass.cpp b/libcxx/test/std/strings/basic.string/string.starts_with/starts_with.char.pass.cpp
index bc9fb26a5d21887b2799a9b848a783ac87917187..8eae5f7c86c97dd63312bccf8c12a386c94d0d8b 100644
--- a/libcxx/test/std/strings/basic.string/string.starts_with/starts_with.char.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.starts_with/starts_with.char.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -30,4 +30,6 @@ int main()
     assert ( s2.starts_with('a'));
     assert (!s2.starts_with('x'));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.starts_with/starts_with.ptr.pass.cpp b/libcxx/test/std/strings/basic.string/string.starts_with/starts_with.ptr.pass.cpp
index ff46fc33d91d1bb1e5877ab8dc2386facece9e0c..412ed574c78189bdf32184599a408481b545f67b 100644
--- a/libcxx/test/std/strings/basic.string/string.starts_with/starts_with.ptr.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.starts_with/starts_with.ptr.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -58,4 +58,6 @@ int main()
     assert (!sNot.starts_with("abcde"));
     assert ( sNot.starts_with("def"));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/string.starts_with/starts_with.string_view.pass.cpp b/libcxx/test/std/strings/basic.string/string.starts_with/starts_with.string_view.pass.cpp
index acb90a0c8b1a3e3a5f184579e413fb3dde30307f..c951b4c737458cdbde6e847d8fddee0d46db5755 100644
--- a/libcxx/test/std/strings/basic.string/string.starts_with/starts_with.string_view.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.starts_with/starts_with.string_view.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string S;
@@ -68,4 +68,6 @@ int main()
     assert (!sNot.starts_with(sv5));
     assert ( sNot.starts_with(svNot));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/traits_mismatch.fail.cpp b/libcxx/test/std/strings/basic.string/traits_mismatch.fail.cpp
index 7e57ae1a7b14ca4e4b3629a6815de436f7eb4acd..47524d2c34d90367bf9053c7c07108149bcfd1d5 100644
--- a/libcxx/test/std/strings/basic.string/traits_mismatch.fail.cpp
+++ b/libcxx/test/std/strings/basic.string/traits_mismatch.fail.cpp
@@ -11,7 +11,9 @@
 
 #include <string>
 
-int main()
+int main(int, char**)
 {
     std::basic_string<char, std::char_traits<wchar_t>> s;
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/basic.string/types.pass.cpp b/libcxx/test/std/strings/basic.string/types.pass.cpp
index 0d074fe05fb31d2cbff5db6c1998363bbb8c4ff1..5aa2c7cf8bebd09b3107c005199e3310fe079c67 100644
--- a/libcxx/test/std/strings/basic.string/types.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/types.pass.cpp
@@ -70,7 +70,7 @@ test()
     static_assert(S::npos == -1, "");
 }
 
-int main()
+int main(int, char**)
 {
     test<test_traits<char>, test_allocator<char> >();
     test<std::char_traits<wchar_t>, std::allocator<wchar_t> >();
@@ -81,4 +81,6 @@ int main()
 #if TEST_STD_VER >= 11
     test<std::char_traits<char>, min_allocator<char> >();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/c.strings/cctype.pass.cpp b/libcxx/test/std/strings/c.strings/cctype.pass.cpp
index feb5c29d22f044508863079beb5e84183e142f67..c26c1e6a20fcb7beaf1fdcbc6275f885c3390ea8 100644
--- a/libcxx/test/std/strings/c.strings/cctype.pass.cpp
+++ b/libcxx/test/std/strings/c.strings/cctype.pass.cpp
@@ -70,7 +70,7 @@
 #error toupper defined
 #endif
 
-int main()
+int main(int, char**)
 {
 
     ASSERT_SAME_TYPE(int, decltype(std::isalnum(0)));
@@ -102,4 +102,6 @@ int main()
     assert( std::isxdigit('a'));
     assert( std::tolower('A') == 'a');
     assert( std::toupper('a') == 'A');
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/c.strings/cstring.pass.cpp b/libcxx/test/std/strings/c.strings/cstring.pass.cpp
index c61f5c4ff8ae2654fda124d768632fa99e940375..c8ee2789df47ac3056dda05bfbf820f5bb962ae6 100644
--- a/libcxx/test/std/strings/c.strings/cstring.pass.cpp
+++ b/libcxx/test/std/strings/c.strings/cstring.pass.cpp
@@ -17,7 +17,7 @@
 #error NULL not defined
 #endif
 
-int main()
+int main(int, char**)
 {
     std::size_t s = 0;
     void* vp = 0;
@@ -60,4 +60,6 @@ int main()
     ASSERT_SAME_TYPE(const char*, decltype(std::strrchr(cpc, 0)));
     ASSERT_SAME_TYPE(const char*, decltype(std::strstr(cpc, cpc)));
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/c.strings/cuchar.pass.cpp b/libcxx/test/std/strings/c.strings/cuchar.pass.cpp
index 989ca6b04275eca498bc6a41d36fa501ddf89c95..4271503d4e24208d628ae03c4b6149481f71da6c 100644
--- a/libcxx/test/std/strings/c.strings/cuchar.pass.cpp
+++ b/libcxx/test/std/strings/c.strings/cuchar.pass.cpp
@@ -14,6 +14,8 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/c.strings/cwchar.pass.cpp b/libcxx/test/std/strings/c.strings/cwchar.pass.cpp
index c7558859e1ba88e730f21ce067e5fd758fecdc73..667910bc1a1f29e009d66bc12b45dd529f896878 100644
--- a/libcxx/test/std/strings/c.strings/cwchar.pass.cpp
+++ b/libcxx/test/std/strings/c.strings/cwchar.pass.cpp
@@ -31,7 +31,7 @@
 #error WEOF not defined
 #endif
 
-int main()
+int main(int, char**)
 {
     std::mbstate_t mb = {};
     std::size_t s = 0;
@@ -128,4 +128,6 @@ int main()
     ASSERT_SAME_TYPE(int,                decltype(std::vwprintf(L"", va)));
     ASSERT_SAME_TYPE(int,                decltype(std::wprintf(L"")));
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/c.strings/cwctype.pass.cpp b/libcxx/test/std/strings/c.strings/cwctype.pass.cpp
index a7d9560d71ea2454fa4489e13cf9b2622acc32c5..3bcda1a472c80a893989d25fefd1c047a39f01e4 100644
--- a/libcxx/test/std/strings/c.strings/cwctype.pass.cpp
+++ b/libcxx/test/std/strings/c.strings/cwctype.pass.cpp
@@ -90,7 +90,7 @@
 #error wctrans defined
 #endif
 
-int main()
+int main(int, char**)
 {
     std::wint_t w = 0;
     ASSERT_SAME_TYPE(int, decltype(std::iswalnum(w)));
@@ -113,4 +113,6 @@ int main()
     ASSERT_SAME_TYPE(std::wint_t,    decltype(std::towupper(w)));
     ASSERT_SAME_TYPE(std::wint_t,    decltype(std::towctrans(w, std::wctrans_t())));
     ASSERT_SAME_TYPE(std::wctrans_t, decltype(std::wctrans("")));
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.require/nothing_to_do.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.require/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.require/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.require/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/assign2.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/assign2.pass.cpp
index 8f80a53ed706d686bb4ec00164b4d1f5a62259cd..c60e6db9fc47fc85683cc603ba2da453d76afdd7 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/assign2.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/assign2.pass.cpp
@@ -27,7 +27,7 @@ constexpr bool test_constexpr()
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     char c = '\0';
     std::char_traits<char>::assign(c, 'a');
@@ -36,4 +36,6 @@ int main()
 #if TEST_STD_VER > 14
     static_assert(test_constexpr(), "" );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/assign3.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/assign3.pass.cpp
index 74e0f907672f9a3ed6b733c4e0bc190512b64376..e2cbe3d5dbe0d9f497fd8115da75dc83dd02cd69 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/assign3.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/assign3.pass.cpp
@@ -15,7 +15,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     char s2[3] = {0};
     assert(std::char_traits<char>::assign(s2, 3, char(5)) == s2);
@@ -23,4 +23,6 @@ int main()
     assert(s2[1] == char(5));
     assert(s2[2] == char(5));
     assert(std::char_traits<char>::assign(NULL, 0, char(5)) == NULL);
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/compare.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/compare.pass.cpp
index 637095127bce3f4a15692a28bb48454154a67133..4926b6296e73bde1c8eb49b7554a0cbc29435e86 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/compare.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/compare.pass.cpp
@@ -27,7 +27,7 @@ constexpr bool test_constexpr()
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     assert(std::char_traits<char>::compare("", "", 0) == 0);
     assert(std::char_traits<char>::compare(NULL, NULL, 0) == 0);
@@ -53,4 +53,6 @@ int main()
 #if TEST_STD_VER > 14
     static_assert(test_constexpr(), "" );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/copy.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/copy.pass.cpp
index bd12bfd21e40ece5c53e67cc7b8c6cf97898ae71..3a8e3bda6bc1729d20413417a495fa22ab89a057 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/copy.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/copy.pass.cpp
@@ -15,7 +15,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     char s1[] = {1, 2, 3};
     char s2[3] = {0};
@@ -25,4 +25,6 @@ int main()
     assert(s2[2] == char(3));
     assert(std::char_traits<char>::copy(NULL, s1, 0) == NULL);
     assert(std::char_traits<char>::copy(s1, NULL, 0) == s1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/eof.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/eof.pass.cpp
index ad99e30b24e2085d9b8f8e9e997e940acb71a9ad..0ea0995da1fd0b652c549b53f2a6de6a5a7996dd 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/eof.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/eof.pass.cpp
@@ -15,7 +15,9 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert(std::char_traits<char>::eof() == EOF);
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/eq.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/eq.pass.cpp
index 7895baf997519bc018c718efcc95c7116d91420c..f0cef792d145601aa157dda3d38342a0e972b60b 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/eq.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/eq.pass.cpp
@@ -15,8 +15,10 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert(std::char_traits<char>::eq('a', 'a'));
     assert(!std::char_traits<char>::eq('a', 'A'));
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/eq_int_type.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/eq_int_type.pass.cpp
index ca6808f865c13954ffb364db6d11409e23f566a0..0fbb4389c601566aa8353cc01c5b0ba8e3374e3f 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/eq_int_type.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/eq_int_type.pass.cpp
@@ -15,11 +15,13 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert( std::char_traits<char>::eq_int_type('a', 'a'));
     assert(!std::char_traits<char>::eq_int_type('a', 'A'));
     assert(!std::char_traits<char>::eq_int_type(std::char_traits<char>::eof(), 'A'));
     assert( std::char_traits<char>::eq_int_type(std::char_traits<char>::eof(),
                                                 std::char_traits<char>::eof()));
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/find.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/find.pass.cpp
index 242d3a17392cd41e16c547daa44f50dd04701c00..974500840800299594c508333e6e51ca05ded9b3 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/find.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/find.pass.cpp
@@ -29,7 +29,7 @@ constexpr bool test_constexpr()
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     char s1[] = {1, 2, 3};
     assert(std::char_traits<char>::find(s1, 3, char(1)) == s1);
@@ -42,4 +42,6 @@ int main()
 #if TEST_STD_VER > 14
     static_assert(test_constexpr(), "" );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/length.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/length.pass.cpp
index f556c952eac473a11acdbe0cfa9060e861a28733..8be4e0a7055193e7094540695ff85b9cae903034 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/length.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/length.pass.cpp
@@ -27,7 +27,7 @@ constexpr bool test_constexpr()
 #endif
 
 
-int main()
+int main(int, char**)
 {
     assert(std::char_traits<char>::length("") == 0);
     assert(std::char_traits<char>::length("a") == 1);
@@ -38,4 +38,6 @@ int main()
 #if TEST_STD_VER > 14
     static_assert(test_constexpr(), "" );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/lt.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/lt.pass.cpp
index 497679636ec9c9c3d13fa7f6dd74b21025af120d..e62090cf4c467f1948bb596f37cd2856a372679a 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/lt.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/lt.pass.cpp
@@ -15,7 +15,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert( std::char_traits<char>::lt('\0', 'A'));
     assert(!std::char_traits<char>::lt('A', '\0'));
@@ -29,4 +29,6 @@ int main()
 
     assert( std::char_traits<char>::lt(' ', 'A'));
     assert( std::char_traits<char>::lt('A', '~'));
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/move.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/move.pass.cpp
index c1f885939ba5c4b8077eba00773418aea2dd5d0d..ecbb61901a908efe01f9704eff93353800f9cce7 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/move.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/move.pass.cpp
@@ -15,7 +15,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     char s1[] = {1, 2, 3};
     assert(std::char_traits<char>::move(s1, s1+1, 2) == s1);
@@ -29,4 +29,6 @@ int main()
     assert(s1[2] == char(3));
     assert(std::char_traits<char>::move(NULL, s1, 0) == NULL);
     assert(std::char_traits<char>::move(s1, NULL, 0) == s1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/not_eof.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/not_eof.pass.cpp
index 01568e5a4285ce69efae5150d3f34a65ef286d94..1c37a7c2efbafafca6eaad3eb62d530d89474770 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/not_eof.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/not_eof.pass.cpp
@@ -15,11 +15,13 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert(std::char_traits<char>::not_eof('a') == 'a');
     assert(std::char_traits<char>::not_eof('A') == 'A');
     assert(std::char_traits<char>::not_eof(0) == 0);
     assert(std::char_traits<char>::not_eof(std::char_traits<char>::eof()) !=
            std::char_traits<char>::eof());
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/to_char_type.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/to_char_type.pass.cpp
index fbf8f2f584b9330f282c646ac2b776a33d364d59..d8a957016f9d89c1a24e418d4c208e07f80575f3 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/to_char_type.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/to_char_type.pass.cpp
@@ -15,9 +15,11 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert(std::char_traits<char>::to_char_type('a') == 'a');
     assert(std::char_traits<char>::to_char_type('A') == 'A');
     assert(std::char_traits<char>::to_char_type(0) == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/to_int_type.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/to_int_type.pass.cpp
index eb8df3b6913f31bb6dfc1eeb7f20534efb0353d7..dd903f9e6c02dd8646aff006a248adbee6ccba4c 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/to_int_type.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/to_int_type.pass.cpp
@@ -15,9 +15,11 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert(std::char_traits<char>::to_int_type('a') == 'a');
     assert(std::char_traits<char>::to_int_type('A') == 'A');
     assert(std::char_traits<char>::to_int_type(0) == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/types.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/types.pass.cpp
index 6439c1ea07e570160af617db986b31d842d9554a..30d31ebc920fb898258794217ffe53a8838c5560 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/types.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char/types.pass.cpp
@@ -19,11 +19,13 @@
 #include <string>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::char_traits<char>::char_type, char>::value), "");
     static_assert((std::is_same<std::char_traits<char>::int_type, int>::value), "");
     static_assert((std::is_same<std::char_traits<char>::off_type, std::streamoff>::value), "");
     static_assert((std::is_same<std::char_traits<char>::pos_type, std::streampos>::value), "");
     static_assert((std::is_same<std::char_traits<char>::state_type, std::mbstate_t>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/assign2.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/assign2.pass.cpp
index 77b8687e8c69c9dd1f2cb75e7bf35dacaecbdd0c..017d0e7acce4f3972916c61255dcab996f11fe01 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/assign2.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/assign2.pass.cpp
@@ -27,7 +27,7 @@ constexpr bool test_constexpr()
 }
 #endif
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
 #if TEST_STD_VER >= 11
@@ -40,4 +40,6 @@ int main()
     static_assert(test_constexpr(), "" );
 #endif
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/assign3.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/assign3.pass.cpp
index c623baa248cb39654bb66c85048c1623f4b85293..8838b81e14b4f35bb269e347ca4c03bba255459b 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/assign3.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/assign3.pass.cpp
@@ -15,7 +15,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
     char16_t s2[3] = {0};
@@ -25,4 +25,6 @@ int main()
     assert(s2[2] == char16_t(5));
     assert(std::char_traits<char16_t>::assign(NULL, 0, char16_t(5)) == NULL);
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/compare.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/compare.pass.cpp
index 2e3b18aca07ddc5a8bab13660c7dc986426596b6..d0782c0933880610495b374f1a9505f12e587bf7 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/compare.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/compare.pass.cpp
@@ -28,7 +28,7 @@ constexpr bool test_constexpr()
 #endif
 
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
 #if TEST_STD_VER >= 11
@@ -58,4 +58,6 @@ int main()
     static_assert(test_constexpr(), "" );
 #endif
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/copy.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/copy.pass.cpp
index 0bf5d47eeb5f57dac8736a0d677af25a9ada8d5e..102f15acdee3e3c8bf912178f644489ebaeae7cd 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/copy.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/copy.pass.cpp
@@ -15,7 +15,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
     char16_t s1[] = {1, 2, 3};
@@ -27,4 +27,6 @@ int main()
     assert(std::char_traits<char16_t>::copy(NULL, s1, 0) == NULL);
     assert(std::char_traits<char16_t>::copy(s1, NULL, 0) == s1);
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/eof.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/eof.pass.cpp
index bb0a4506a9a53b9918670fda21013c0589a7bc93..c80b0792a49235fe51b332c5c4e4ff81354c0539 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/eof.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/eof.pass.cpp
@@ -15,10 +15,12 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
     std::char_traits<char16_t>::int_type i = std::char_traits<char16_t>::eof();
     ((void)i); // Prevent unused warning
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/eq.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/eq.pass.cpp
index f4abe84dbd64d0f2f9e600d1e1322cac8877d20b..1c705109f2859b99376a2702f534328d0a29b78b 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/eq.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/eq.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
 #if TEST_STD_VER >= 11
@@ -25,4 +25,6 @@ int main()
     assert(!std::char_traits<char16_t>::eq(u'a', u'A'));
 #endif
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/eq_int_type.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/eq_int_type.pass.cpp
index 9a24cf13d0c838579533cf4f34ff8dcb0aac9bc7..bef97d612eb77e8123b1cfdf8adb1a6930dc1339 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/eq_int_type.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/eq_int_type.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
 #if TEST_STD_VER >= 11
@@ -28,4 +28,6 @@ int main()
     assert( std::char_traits<char16_t>::eq_int_type(std::char_traits<char16_t>::eof(),
                                                     std::char_traits<char16_t>::eof()));
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/find.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/find.pass.cpp
index cd31e5925dea4d075a542f62b3f9507d64684f45..2ca7e534327cca91f933932ae16815515e768b28 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/find.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/find.pass.cpp
@@ -29,7 +29,7 @@ constexpr bool test_constexpr()
 }
 #endif
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
     char16_t s1[] = {1, 2, 3};
@@ -44,4 +44,6 @@ int main()
     static_assert(test_constexpr(), "" );
 #endif
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/length.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/length.pass.cpp
index 2a2a35702fc0cebc61dc2de7780a66ce94fbe01a..f487c410b0b7278ef8562cca29d103e893901b38 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/length.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/length.pass.cpp
@@ -26,7 +26,7 @@ constexpr bool test_constexpr()
 }
 #endif
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
 #if TEST_STD_VER >= 11
@@ -41,4 +41,6 @@ int main()
     static_assert(test_constexpr(), "" );
 #endif
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/lt.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/lt.pass.cpp
index 4ade9b6f06d6bcda6591e65582d431eaf0db8f73..a43a9e45cc2b783fdf211f477547aef4e8a3531d 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/lt.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/lt.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
 #if TEST_STD_VER >= 11
@@ -25,4 +25,6 @@ int main()
     assert( std::char_traits<char16_t>::lt(u'A', u'a'));
 #endif
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/move.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/move.pass.cpp
index ddf07a022c92a05efd6faaad92abb19a2f4b4b00..aa55e0d11ce904214d68c0ae391d3218309aa790 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/move.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/move.pass.cpp
@@ -15,7 +15,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
     char16_t s1[] = {1, 2, 3};
@@ -31,4 +31,6 @@ int main()
     assert(std::char_traits<char16_t>::move(NULL, s1, 0) == NULL);
     assert(std::char_traits<char16_t>::move(s1, NULL, 0) == s1);
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/not_eof.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/not_eof.pass.cpp
index ea6f0ab17cdb639392ae6f2dbe35851976bf25bf..bf26b4cf330908af868325726460ec61b1048994 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/not_eof.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/not_eof.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
 #if TEST_STD_VER >= 11
@@ -28,4 +28,6 @@ int main()
     assert(std::char_traits<char16_t>::not_eof(std::char_traits<char16_t>::eof()) !=
            std::char_traits<char16_t>::eof());
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/to_char_type.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/to_char_type.pass.cpp
index 9256a528172c32e1dea5a9c446eb46a37331c1d0..738754bf9838a66319fb5dd5a180b80a8871c2ef 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/to_char_type.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/to_char_type.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
 #if TEST_STD_VER >= 11
@@ -26,4 +26,6 @@ int main()
 #endif
     assert(std::char_traits<char16_t>::to_char_type(0) == 0);
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/to_int_type.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/to_int_type.pass.cpp
index 411f5202b11cd16ea06ba7bfb6226ae2354a5639..83fff60b8865f53647855b86dcbe7353fbcd22ac 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/to_int_type.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/to_int_type.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
 #if TEST_STD_VER >= 11
@@ -26,4 +26,6 @@ int main()
 #endif
     assert(std::char_traits<char16_t>::to_int_type(0) == 0);
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/types.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/types.pass.cpp
index ae8792c49011988cafe03b4a1a5abe79bfea3b5c..41e3fd4d57b1a348b368675fb629a3c2be0f7c31 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/types.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char16_t/types.pass.cpp
@@ -20,7 +20,7 @@
 #include <type_traits>
 #include <cstdint>
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
     static_assert((std::is_same<std::char_traits<char16_t>::char_type, char16_t>::value), "");
@@ -29,4 +29,6 @@ int main()
     static_assert((std::is_same<std::char_traits<char16_t>::pos_type, std::u16streampos>::value), "");
     static_assert((std::is_same<std::char_traits<char16_t>::state_type, std::mbstate_t>::value), "");
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/assign2.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/assign2.pass.cpp
index 90388aa43f82a7390e4e48655d5e16a2bae040a7..f77d54f79162403602ef22dedcf6e6d9e4c48e3a 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/assign2.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/assign2.pass.cpp
@@ -27,7 +27,7 @@ constexpr bool test_constexpr()
 }
 #endif
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
 #if TEST_STD_VER >= 11
@@ -40,4 +40,6 @@ int main()
     static_assert(test_constexpr(), "" );
 #endif
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/assign3.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/assign3.pass.cpp
index af69fdcfa2af6a7b5371f814572daedb92d0a44b..26985481c1f4fa0429a606458b911f87ce088cd0 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/assign3.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/assign3.pass.cpp
@@ -15,7 +15,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
     char32_t s2[3] = {0};
@@ -25,4 +25,6 @@ int main()
     assert(s2[2] == char32_t(5));
     assert(std::char_traits<char32_t>::assign(NULL, 0, char32_t(5)) == NULL);
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/compare.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/compare.pass.cpp
index 5d1cfa84248e001c7f22693748951c12704efa1c..f2dd01ac9aa6a5e75c9949533ae83f71493fc50d 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/compare.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/compare.pass.cpp
@@ -27,7 +27,7 @@ constexpr bool test_constexpr()
 }
 #endif
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
 #if TEST_STD_VER >= 11
@@ -57,4 +57,6 @@ int main()
     static_assert(test_constexpr(), "" );
 #endif
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/copy.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/copy.pass.cpp
index d9f983b5bd6b0dddbbe263b1a8a32cfd8cc16dbc..8b2d6ce907428cf11c6c52a517947ee5308fa3f4 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/copy.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/copy.pass.cpp
@@ -15,7 +15,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
     char32_t s1[] = {1, 2, 3};
@@ -27,4 +27,6 @@ int main()
     assert(std::char_traits<char32_t>::copy(NULL, s1, 0) == NULL);
     assert(std::char_traits<char32_t>::copy(s1, NULL, 0) == s1);
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/eof.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/eof.pass.cpp
index ac042907ab86cf00c771818d08c84b448ee13924..5c28f47bb4839452512eda26fcb85454262176c5 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/eof.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/eof.pass.cpp
@@ -15,10 +15,12 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
     std::char_traits<char32_t>::int_type i = std::char_traits<char32_t>::eof();
     ((void)i); // Prevent unused warning
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/eq.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/eq.pass.cpp
index aef7ebb703dbec2aa073ec77a40fc1c586ca2624..516f38bd08715d640901284667b462a4ed22a83a 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/eq.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/eq.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
 #if TEST_STD_VER >= 11
@@ -25,4 +25,6 @@ int main()
     assert(!std::char_traits<char32_t>::eq(U'a', U'A'));
 #endif
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/eq_int_type.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/eq_int_type.pass.cpp
index 91b2fb0fbada958eb1c87a75def3c729e3358556..5d241159f72ecab7a09053351272f2def6599092 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/eq_int_type.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/eq_int_type.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
 #if TEST_STD_VER >= 11
@@ -28,4 +28,6 @@ int main()
     assert( std::char_traits<char32_t>::eq_int_type(std::char_traits<char32_t>::eof(),
                                                     std::char_traits<char32_t>::eof()));
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/find.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/find.pass.cpp
index ac1723a6535e24abd843dfbfb642008215e90684..5a89596dee9dc83c7cc5134709dc736611ee49e6 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/find.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/find.pass.cpp
@@ -29,7 +29,7 @@ constexpr bool test_constexpr()
 }
 #endif
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
     char32_t s1[] = {1, 2, 3};
@@ -44,4 +44,6 @@ int main()
     static_assert(test_constexpr(), "" );
 #endif
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/length.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/length.pass.cpp
index c4c01ddf1a477be57d707d71f759441f591cf821..ef2ea3419bd299b75f60660ea9c878813c04ebda 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/length.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/length.pass.cpp
@@ -26,7 +26,7 @@ constexpr bool test_constexpr()
 }
 #endif
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
 #if TEST_STD_VER >= 11
@@ -41,4 +41,6 @@ int main()
     static_assert(test_constexpr(), "" );
 #endif
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/lt.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/lt.pass.cpp
index d3fe9a4516e12c4b62ef4535eaa5bee5d140b577..51c1faf9ef2b3425741444a8c2b004c977e12f8d 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/lt.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/lt.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
 #if TEST_STD_VER >= 11
@@ -25,4 +25,6 @@ int main()
     assert( std::char_traits<char32_t>::lt(U'A', U'a'));
 #endif
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/move.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/move.pass.cpp
index 0ac49d0c9c32155aeb7c85c0fc49442b88630c13..7cda99bd8300e7aa8fefc6658367d79de9943db0 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/move.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/move.pass.cpp
@@ -15,7 +15,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
     char32_t s1[] = {1, 2, 3};
@@ -31,4 +31,6 @@ int main()
     assert(std::char_traits<char32_t>::move(NULL, s1, 0) == NULL);
     assert(std::char_traits<char32_t>::move(s1, NULL, 0) == s1);
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/not_eof.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/not_eof.pass.cpp
index dbe1dfe8b302496044b47079b4af5b4b2f1f2f9f..aeba1228e6f63a1adaeaca99c4d41c979cf7639f 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/not_eof.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/not_eof.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
 #if TEST_STD_VER >= 11
@@ -28,4 +28,6 @@ int main()
     assert(std::char_traits<char32_t>::not_eof(std::char_traits<char32_t>::eof()) !=
            std::char_traits<char32_t>::eof());
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/to_char_type.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/to_char_type.pass.cpp
index 1c16a55b81181b87ce9f45764dd628f4107cca6f..75104e7bf1687cd2e90494114a0ce4ee5d7e81fc 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/to_char_type.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/to_char_type.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
 #if TEST_STD_VER >= 11
@@ -26,4 +26,6 @@ int main()
 #endif
     assert(std::char_traits<char32_t>::to_char_type(0) == 0);
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/to_int_type.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/to_int_type.pass.cpp
index 4ec9a9b631f77638b6f08b8253e9a0493029ab4c..8299e94dabdba605d0dc61437d9b2441e57fea8b 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/to_int_type.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/to_int_type.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
 #if TEST_STD_VER >= 11
@@ -26,4 +26,6 @@ int main()
 #endif
     assert(std::char_traits<char32_t>::to_int_type(0) == 0);
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/types.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/types.pass.cpp
index 65624dd5efd51a6bb6bc1bd17dee85fd3272de46..5ec558f54700cfcd671d0e45494f6988309d2733 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/types.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char32_t/types.pass.cpp
@@ -20,7 +20,7 @@
 #include <type_traits>
 #include <cstdint>
 
-int main()
+int main(int, char**)
 {
 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
     static_assert((std::is_same<std::char_traits<char32_t>::char_type, char32_t>::value), "");
@@ -29,4 +29,6 @@ int main()
     static_assert((std::is_same<std::char_traits<char32_t>::pos_type, std::u32streampos>::value), "");
     static_assert((std::is_same<std::char_traits<char32_t>::state_type, std::mbstate_t>::value), "");
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/assign2.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/assign2.pass.cpp
index b14662d09be3345a4620afb561c5a9635ecff26a..c669ab9c1a650b94e02fffe4e7610ab881dae03a 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/assign2.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/assign2.pass.cpp
@@ -25,7 +25,7 @@ constexpr bool test_constexpr()
     return c == u'a';
 }
 
-int main()
+int main(int, char**)
 {
     char8_t c = u8'\0';
     std::char_traits<char8_t>::assign(c, u8'a');
@@ -34,5 +34,7 @@ int main()
     static_assert(test_constexpr(), "");
 }
 #else
-int main () {}
+int main(int, char**) {
+  return 0;
+}
 #endif
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/assign3.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/assign3.pass.cpp
index eae7c82ba86e555a361f106ff7afe28bf401c974..f9c176e9b2f50f2a8fb3cb5631e3bc2a65ce0672 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/assign3.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/assign3.pass.cpp
@@ -16,7 +16,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
     char8_t s2[3] = {0};
@@ -26,4 +26,6 @@ int main()
     assert(s2[2] == char8_t(5));
     assert(std::char_traits<char8_t>::assign(NULL, 0, char8_t(5)) == NULL);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/compare.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/compare.pass.cpp
index 0ac815b9b178766f3de3ba519f8428b49a310938..063ab5dc51625aca0e122f662c7373cb0310c22d 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/compare.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/compare.pass.cpp
@@ -27,7 +27,7 @@ constexpr bool test_constexpr()
 }
 
 
-int main()
+int main(int, char**)
 {
     assert(std::char_traits<char8_t>::compare(u8"", u8"", 0) == 0);
     assert(std::char_traits<char8_t>::compare(NULL, NULL, 0) == 0);
@@ -53,5 +53,7 @@ int main()
     static_assert(test_constexpr(), "" );
 }
 #else
-int main () {}
+int main(int, char**) {
+  return 0;
+}
 #endif
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/copy.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/copy.pass.cpp
index 2f091029b06f602f58f512cd2efe48bdbf5777f1..7bf949197a84cba622ee5a2e47b50b03c098fe18 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/copy.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/copy.pass.cpp
@@ -16,7 +16,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
     char8_t s1[] = {1, 2, 3};
@@ -28,4 +28,6 @@ int main()
     assert(std::char_traits<char8_t>::copy(NULL, s1, 0) == NULL);
     assert(std::char_traits<char8_t>::copy(s1, NULL, 0) == s1);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/eof.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/eof.pass.cpp
index 9d13d7dd0a601bbd68b96c7159f46cb23450a524..e112556886dcf6145e61b1f33c6a699f606d878e 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/eof.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/eof.pass.cpp
@@ -16,10 +16,12 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
     std::char_traits<char8_t>::int_type i = std::char_traits<char8_t>::eof();
     ((void)i); // Prevent unused warning
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/eq.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/eq.pass.cpp
index 4d334110f36283325eb62862e1add784e5b58cf0..6e32c85bbe3e4435aa30adb6b1e5bf6f1809687e 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/eq.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/eq.pass.cpp
@@ -18,10 +18,12 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
     assert( std::char_traits<char8_t>::eq(u8'a', u8'a'));
     assert(!std::char_traits<char8_t>::eq(u8'a', u8'A'));
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/eq_int_type.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/eq_int_type.pass.cpp
index 6cc58eba1dbf796217dddeeb5415aa15c369a84f..8c5e19717478b2bea25aae07990b4df75d486037 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/eq_int_type.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/eq_int_type.pass.cpp
@@ -18,7 +18,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
     assert( std::char_traits<char8_t>::eq_int_type(u8'a', u8'a'));
@@ -27,4 +27,6 @@ int main()
     assert( std::char_traits<char8_t>::eq_int_type(std::char_traits<char8_t>::eof(),
                                                     std::char_traits<char8_t>::eof()));
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/find.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/find.pass.cpp
index 9d2e62e348cb30b92dc77a4b77880696858fdaea..170539e0694e1a15bc0bd3dc85273a4ae3677d1d 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/find.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/find.pass.cpp
@@ -28,7 +28,7 @@ constexpr bool test_constexpr()
         && std::char_traits<char8_t>::find(p, 3, u8'4') == nullptr;
 }
 
-int main()
+int main(int, char**)
 {
     char8_t s1[] = {1, 2, 3};
     assert(std::char_traits<char8_t>::find(s1, 3, char8_t(1)) == s1);
@@ -41,5 +41,7 @@ int main()
     static_assert(test_constexpr(), "" );
 }
 #else
-int main () {}
+int main(int, char**) {
+  return 0;
+}
 #endif
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/length.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/length.pass.cpp
index 10f800127b6f26c80914285821723b4024fc906a..ce2c717cc572455496f88819579f5df17247dc5b 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/length.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/length.pass.cpp
@@ -25,7 +25,7 @@ constexpr bool test_constexpr()
         && std::char_traits<char8_t>::length(u8"abcd") == 4;
 }
 
-int main()
+int main(int, char**)
 {
     assert(std::char_traits<char8_t>::length(u8"") == 0);
     assert(std::char_traits<char8_t>::length(u8"a") == 1);
@@ -36,5 +36,7 @@ int main()
     static_assert(test_constexpr(), "");
 }
 #else
-int main() { }
+int main(int, char**) { 
+  return 0;
+}
 #endif
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/lt.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/lt.pass.cpp
index 4653007bf7275c633166e54fab9bad8781f736e5..a4fb1251203029fca457a778433af28ee56a9832 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/lt.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/lt.pass.cpp
@@ -18,10 +18,12 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
     assert(!std::char_traits<char8_t>::lt(u8'a', u8'a'));
     assert( std::char_traits<char8_t>::lt(u8'A', u8'a'));
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/move.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/move.pass.cpp
index 5ca536966cd49e166766e9eff3283f538029472b..a5e1359dd4d77dbee0665456f29570f7523ee536 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/move.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/move.pass.cpp
@@ -16,7 +16,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
     char8_t s1[] = {1, 2, 3};
@@ -32,4 +32,6 @@ int main()
     assert(std::char_traits<char8_t>::move(NULL, s1, 0) == NULL);
     assert(std::char_traits<char8_t>::move(s1, NULL, 0) == s1);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/not_eof.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/not_eof.pass.cpp
index 69e8ddac8cc4e3bb196fdc608f78819ec096cc6d..3d1141d72d723eed66f2a3402bdaa3eeff2b2cd6 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/not_eof.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/not_eof.pass.cpp
@@ -18,7 +18,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
     assert(std::char_traits<char8_t>::not_eof(u8'a') == u8'a');
@@ -27,4 +27,6 @@ int main()
     assert(std::char_traits<char8_t>::not_eof(std::char_traits<char8_t>::eof()) !=
            std::char_traits<char8_t>::eof());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/to_char_type.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/to_char_type.pass.cpp
index 0b021d2834029ee2062b9e4b7fd78eb831150400..4edc49452efe0c2065ecec90b0b68180890134b8 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/to_char_type.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/to_char_type.pass.cpp
@@ -18,11 +18,13 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
     assert(std::char_traits<char8_t>::to_char_type(u8'a') == u8'a');
     assert(std::char_traits<char8_t>::to_char_type(u8'A') == u8'A');
     assert(std::char_traits<char8_t>::to_char_type(0) == 0);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/to_int_type.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/to_int_type.pass.cpp
index 98974ab86b1abdbc7f83c1ee96ce19c0cc3191de..ab3c9dc7993a991597e6984952b95168e32dd138 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/to_int_type.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/to_int_type.pass.cpp
@@ -18,11 +18,13 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
     assert(std::char_traits<char8_t>::to_int_type(u8'a') == u8'a');
     assert(std::char_traits<char8_t>::to_int_type(u8'A') == u8'A');
     assert(std::char_traits<char8_t>::to_int_type(0) == 0);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/types.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/types.pass.cpp
index cfb20faaf751d0cea3f69aab488669a63a3cabc2..245dcd87d99cf2fcf834f772a66856e1868f897a 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/types.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/types.pass.cpp
@@ -21,7 +21,7 @@
 #include <type_traits>
 #include <cstdint>
 
-int main()
+int main(int, char**)
 {
 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
     static_assert((std::is_same<std::char_traits<char8_t>::char_type,  char8_t>::value), "");
@@ -30,4 +30,6 @@ int main()
     static_assert((std::is_same<std::char_traits<char8_t>::pos_type,   std::u16streampos>::value), "");
     static_assert((std::is_same<std::char_traits<char8_t>::state_type, std::mbstate_t>::value), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/assign2.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/assign2.pass.cpp
index 9b9b0ea491c7107276409dbee9c6fed91887dbc1..25e427014483f023745bedb93b17d8a2239a8ef2 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/assign2.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/assign2.pass.cpp
@@ -27,7 +27,7 @@ constexpr bool test_constexpr()
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     wchar_t c = L'\0';
     std::char_traits<wchar_t>::assign(c, L'a');
@@ -36,4 +36,6 @@ int main()
 #if TEST_STD_VER > 14
     static_assert(test_constexpr(), "" );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/assign3.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/assign3.pass.cpp
index 42df4081d50fe389dee1e173a736c161389528a6..d4ed434094581f5feb95a39df705096e64f5f507 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/assign3.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/assign3.pass.cpp
@@ -15,7 +15,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     wchar_t s2[3] = {0};
     assert(std::char_traits<wchar_t>::assign(s2, 3, wchar_t(5)) == s2);
@@ -23,4 +23,6 @@ int main()
     assert(s2[1] == wchar_t(5));
     assert(s2[2] == wchar_t(5));
     assert(std::char_traits<wchar_t>::assign(NULL, 0, wchar_t(5)) == NULL);
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/compare.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/compare.pass.cpp
index d6272f39357f97c85f0badd7f7becfe1fc53bc7f..1c2e11912f83f386669f4a51d724d262df8693e6 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/compare.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/compare.pass.cpp
@@ -27,7 +27,7 @@ constexpr bool test_constexpr()
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     assert(std::char_traits<wchar_t>::compare(L"", L"", 0) == 0);
     assert(std::char_traits<wchar_t>::compare(NULL, NULL, 0) == 0);
@@ -53,4 +53,6 @@ int main()
 #if TEST_STD_VER > 14
     static_assert(test_constexpr(), "" );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/copy.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/copy.pass.cpp
index f90688a9aac766811c7c1f4b8b668a51737db31f..309c21316c4340707fc9c9a5acc4562d5d47cd19 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/copy.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/copy.pass.cpp
@@ -15,7 +15,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     wchar_t s1[] = {1, 2, 3};
     wchar_t s2[3] = {0};
@@ -25,4 +25,6 @@ int main()
     assert(s2[2] == wchar_t(3));
     assert(std::char_traits<wchar_t>::copy(NULL, s1, 0) == NULL);
     assert(std::char_traits<wchar_t>::copy(s1, NULL, 0) == s1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/eof.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/eof.pass.cpp
index 9b466a5f0cc722ad6a109812deb4736de204a505..6190220fe90128e9abfc8ed3973baa11a8db5855 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/eof.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/eof.pass.cpp
@@ -15,7 +15,9 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert(std::char_traits<wchar_t>::eof() == WEOF);
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/eq.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/eq.pass.cpp
index a89a0002da7ae671b8dff6ee6baa81bf703f2a06..701a6502fc6e22fdc5efb81c036e872799d75a8c 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/eq.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/eq.pass.cpp
@@ -15,8 +15,10 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert(std::char_traits<wchar_t>::eq(L'a', L'a'));
     assert(!std::char_traits<wchar_t>::eq(L'a', L'A'));
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/eq_int_type.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/eq_int_type.pass.cpp
index e7e8285ca0f30fc6a600ce88ef309cf574099166..b218186b43f80f7e30663c85e74ce428c45c263e 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/eq_int_type.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/eq_int_type.pass.cpp
@@ -15,11 +15,13 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert( std::char_traits<wchar_t>::eq_int_type(L'a', L'a'));
     assert(!std::char_traits<wchar_t>::eq_int_type(L'a', L'A'));
     assert(!std::char_traits<wchar_t>::eq_int_type(std::char_traits<wchar_t>::eof(), L'A'));
     assert( std::char_traits<wchar_t>::eq_int_type(std::char_traits<wchar_t>::eof(),
                                                    std::char_traits<wchar_t>::eof()));
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/find.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/find.pass.cpp
index ed59397cc2c7dc626b63d42c0cca9e03dc7779e9..78a9ad5c3f90e0bc4ff722f67f0aea6241bf06d2 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/find.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/find.pass.cpp
@@ -29,7 +29,7 @@ constexpr bool test_constexpr()
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     wchar_t s1[] = {1, 2, 3};
     assert(std::char_traits<wchar_t>::find(s1, 3, wchar_t(1)) == s1);
@@ -42,4 +42,6 @@ int main()
 #if TEST_STD_VER > 14
     static_assert(test_constexpr(), "" );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/length.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/length.pass.cpp
index a9176c8d459e3d7b8fddc788efa34be408c06b0e..742189205ab91b63e3d0aae01f2095505ef6bfd8 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/length.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/length.pass.cpp
@@ -26,7 +26,7 @@ constexpr bool test_constexpr()
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     assert(std::char_traits<wchar_t>::length(L"") == 0);
     assert(std::char_traits<wchar_t>::length(L"a") == 1);
@@ -37,4 +37,6 @@ int main()
 #if TEST_STD_VER > 14
     static_assert(test_constexpr(), "" );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/lt.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/lt.pass.cpp
index f7950b782bb6f73c2a5dc126ba86df997fdc7ca4..9abd9cf59d7a7d06029a71759690e7181246d750 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/lt.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/lt.pass.cpp
@@ -15,8 +15,10 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert(!std::char_traits<wchar_t>::lt(L'a', L'a'));
     assert( std::char_traits<wchar_t>::lt(L'A', L'a'));
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/move.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/move.pass.cpp
index d833bc0b5b2a0ea63fa50a5a9e344fa1ed532290..341a90233a838702ce8c6ab147ee9e321b49ecf9 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/move.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/move.pass.cpp
@@ -15,7 +15,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     wchar_t s1[] = {1, 2, 3};
     assert(std::char_traits<wchar_t>::move(s1, s1+1, 2) == s1);
@@ -29,4 +29,6 @@ int main()
     assert(s1[2] == wchar_t(3));
     assert(std::char_traits<wchar_t>::move(NULL, s1, 0) == NULL);
     assert(std::char_traits<wchar_t>::move(s1, NULL, 0) == s1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/not_eof.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/not_eof.pass.cpp
index 751903beae409a898efdf48438b1412ec5f6179e..92f08b1d5200493bd211256879fe6daf79923d66 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/not_eof.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/not_eof.pass.cpp
@@ -15,11 +15,13 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert(std::char_traits<wchar_t>::not_eof(L'a') == L'a');
     assert(std::char_traits<wchar_t>::not_eof(L'A') == L'A');
     assert(std::char_traits<wchar_t>::not_eof(0) == 0);
     assert(std::char_traits<wchar_t>::not_eof(std::char_traits<wchar_t>::eof()) !=
            std::char_traits<wchar_t>::eof());
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/to_char_type.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/to_char_type.pass.cpp
index 7654c32873f7a86752fc88387d62c95e3640b0d0..f479bec9daf4006d0fc16819163395d1f7cc0050 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/to_char_type.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/to_char_type.pass.cpp
@@ -15,9 +15,11 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert(std::char_traits<wchar_t>::to_char_type(L'a') == L'a');
     assert(std::char_traits<wchar_t>::to_char_type(L'A') == L'A');
     assert(std::char_traits<wchar_t>::to_char_type(0) == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/to_int_type.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/to_int_type.pass.cpp
index a003bdc1115a56b48bc16527fa3138ddc5764d5e..11fe2419b1a594cd38e296fad8e6af011c5e7b4e 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/to_int_type.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/to_int_type.pass.cpp
@@ -15,9 +15,11 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert(std::char_traits<wchar_t>::to_int_type(L'a') == L'a');
     assert(std::char_traits<wchar_t>::to_int_type(L'A') == L'A');
     assert(std::char_traits<wchar_t>::to_int_type(0) == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/types.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/types.pass.cpp
index c367be47ef392b09a4ce4b1c32030e1e8faec2f0..9781d55e392baadfcb1478f934b37ac6bd6058dd 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/types.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/types.pass.cpp
@@ -19,11 +19,13 @@
 #include <string>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::char_traits<wchar_t>::char_type, wchar_t>::value), "");
     static_assert((std::is_same<std::char_traits<wchar_t>::int_type, std::wint_t>::value), "");
     static_assert((std::is_same<std::char_traits<wchar_t>::off_type, std::streamoff>::value), "");
     static_assert((std::is_same<std::char_traits<wchar_t>::pos_type, std::wstreampos>::value), "");
     static_assert((std::is_same<std::char_traits<wchar_t>::state_type, std::mbstate_t>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/nothing_to_do.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/char.traits.typedefs/nothing_to_do.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.typedefs/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.typedefs/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.typedefs/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/char.traits/nothing_to_do.pass.cpp b/libcxx/test/std/strings/char.traits/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/strings/char.traits/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.classes/typedefs.pass.cpp b/libcxx/test/std/strings/string.classes/typedefs.pass.cpp
index 14fe38877051145e5c586004d100d12028d63b07..cbc028391b58fd0120fff4acb2fbd94ea5f5347b 100644
--- a/libcxx/test/std/strings/string.classes/typedefs.pass.cpp
+++ b/libcxx/test/std/strings/string.classes/typedefs.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::string, std::basic_string<char> >::value), "");
     static_assert((std::is_same<std::wstring, std::basic_string<wchar_t> >::value), "");
@@ -33,4 +33,6 @@ int main()
     static_assert((std::is_same<std::u16string, std::basic_string<char16_t> >::value), "");
     static_assert((std::is_same<std::u32string, std::basic_string<char32_t> >::value), "");
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.conversions/stod.pass.cpp b/libcxx/test/std/strings/string.conversions/stod.pass.cpp
index 9909497e696c7c60a87b4d4248309b7f82e8a257..d13b695f21c28a76be00c09297d1ea4f828c62fd 100644
--- a/libcxx/test/std/strings/string.conversions/stod.pass.cpp
+++ b/libcxx/test/std/strings/string.conversions/stod.pass.cpp
@@ -18,7 +18,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     assert(std::stod("0") == 0);
     assert(std::stod(L"0") == 0);
@@ -185,4 +185,6 @@ int main()
         assert(idx == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.conversions/stof.pass.cpp b/libcxx/test/std/strings/string.conversions/stof.pass.cpp
index 8e7f4b4ecfc2858a2c191e299f2a5c36981bd4cb..2c8e4c9b927d2456c355655c833511edb50f7fe9 100644
--- a/libcxx/test/std/strings/string.conversions/stof.pass.cpp
+++ b/libcxx/test/std/strings/string.conversions/stof.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     assert(std::stof("0") == 0);
     assert(std::stof(L"0") == 0);
@@ -186,4 +186,6 @@ int main()
         assert(idx == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.conversions/stoi.pass.cpp b/libcxx/test/std/strings/string.conversions/stoi.pass.cpp
index 36998336c2e62226999c93b9e17afbab9ef1fb0b..b3e41633126e22fabb677b59732aa6f15e533a74 100644
--- a/libcxx/test/std/strings/string.conversions/stoi.pass.cpp
+++ b/libcxx/test/std/strings/string.conversions/stoi.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     assert(std::stoi("0") == 0);
     assert(std::stoi(L"0") == 0);
@@ -109,4 +109,6 @@ int main()
         assert(idx == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.conversions/stol.pass.cpp b/libcxx/test/std/strings/string.conversions/stol.pass.cpp
index 8e18a0088cac952a21e538e4555a3536f44a93ed..ef0cbb4ed3c28a1ec28df86c117c62172268f03d 100644
--- a/libcxx/test/std/strings/string.conversions/stol.pass.cpp
+++ b/libcxx/test/std/strings/string.conversions/stol.pass.cpp
@@ -21,7 +21,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     assert(std::stol("0") == 0);
     assert(std::stol(L"0") == 0);
@@ -113,4 +113,6 @@ int main()
         assert(idx == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.conversions/stold.pass.cpp b/libcxx/test/std/strings/string.conversions/stold.pass.cpp
index 4677bd7d2eb45577f5b6dfdf297115ecc7840f20..5b21fd0e34571a586629c49db1431748f128b31c 100644
--- a/libcxx/test/std/strings/string.conversions/stold.pass.cpp
+++ b/libcxx/test/std/strings/string.conversions/stold.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     assert(std::stold("0") == 0);
     assert(std::stold(L"0") == 0);
@@ -188,4 +188,6 @@ int main()
         assert(idx == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.conversions/stoll.pass.cpp b/libcxx/test/std/strings/string.conversions/stoll.pass.cpp
index f8a5a6b0e0fa775ffc9935d53ca53b401905fe06..73d5e82015fcf9f550c81cd88e7d036bde0f6e9c 100644
--- a/libcxx/test/std/strings/string.conversions/stoll.pass.cpp
+++ b/libcxx/test/std/strings/string.conversions/stoll.pass.cpp
@@ -21,7 +21,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     assert(std::stoll("0") == 0);
     assert(std::stoll(L"0") == 0);
@@ -112,4 +112,6 @@ int main()
         assert(idx == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.conversions/stoul.pass.cpp b/libcxx/test/std/strings/string.conversions/stoul.pass.cpp
index e60a6a071ad87f9ef7f594964ff20cbda23347e6..6ef861396cd50dbf43047c4d9f8a5a62b773b2d0 100644
--- a/libcxx/test/std/strings/string.conversions/stoul.pass.cpp
+++ b/libcxx/test/std/strings/string.conversions/stoul.pass.cpp
@@ -21,7 +21,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     assert(std::stoul("0") == 0);
     assert(std::stoul(L"0") == 0);
@@ -111,4 +111,6 @@ int main()
         assert(idx == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.conversions/stoull.pass.cpp b/libcxx/test/std/strings/string.conversions/stoull.pass.cpp
index 32369664d0872bbe75e42ed6a65052fa7a0ab0e1..3e21c683af4e33e58fb9ad2bf63ecd13b5fbc4f5 100644
--- a/libcxx/test/std/strings/string.conversions/stoull.pass.cpp
+++ b/libcxx/test/std/strings/string.conversions/stoull.pass.cpp
@@ -21,7 +21,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     assert(std::stoull("0") == 0);
     assert(std::stoull(L"0") == 0);
@@ -112,4 +112,6 @@ int main()
         assert(idx == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.conversions/to_string.pass.cpp b/libcxx/test/std/strings/string.conversions/to_string.pass.cpp
index 864425134e0677be6ab10a1bfff0ca986e0c0420..23729cd4f49edf82e7cd95deb2addc970734891a 100644
--- a/libcxx/test/std/strings/string.conversions/to_string.pass.cpp
+++ b/libcxx/test/std/strings/string.conversions/to_string.pass.cpp
@@ -112,7 +112,7 @@ test_float()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test_signed<int>();
     test_signed<long>();
@@ -123,4 +123,6 @@ int main()
     test_float<float>();
     test_float<double>();
     test_float<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.conversions/to_wstring.pass.cpp b/libcxx/test/std/strings/string.conversions/to_wstring.pass.cpp
index 82c3f617b9e072ee39a1d09e1becc988cbbcaf31..02a262a0f29ba009a400500d663ec4e7efabfa45 100644
--- a/libcxx/test/std/strings/string.conversions/to_wstring.pass.cpp
+++ b/libcxx/test/std/strings/string.conversions/to_wstring.pass.cpp
@@ -112,7 +112,7 @@ test_float()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test_signed<int>();
     test_signed<long>();
@@ -123,4 +123,6 @@ int main()
     test_float<float>();
     test_float<double>();
     test_float<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/char.bad.fail.cpp b/libcxx/test/std/strings/string.view/char.bad.fail.cpp
index 3d04cd085c52155f03dfddaaef87d6fc1a5c6023..522466613caad214b78013be41a647ba10ca50c7 100644
--- a/libcxx/test/std/strings/string.view/char.bad.fail.cpp
+++ b/libcxx/test/std/strings/string.view/char.bad.fail.cpp
@@ -26,7 +26,7 @@ private:
     int two;
 };
 
-int main()
+int main(int, char**)
 {
     {
 //  array
@@ -49,4 +49,6 @@ int main()
     std::basic_string_view<NotStandardLayout, test_traits<NotStandardLayout> > sv;
 //  expected-error-re@string_view:* {{static_assert failed{{.*}} "Character type of basic_string_view must be standard-layout"}}
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.access/at.pass.cpp b/libcxx/test/std/strings/string.view/string.view.access/at.pass.cpp
index b4b2667bbe28a8b86292122f2677f059f114004e..3d741c33ffbd0b2f316b58cc61909bb7155c256e 100644
--- a/libcxx/test/std/strings/string.view/string.view.access/at.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.access/at.pass.cpp
@@ -36,7 +36,7 @@ void test ( const CharT *s, size_t len ) {
 #endif
 }
 
-int main () {
+int main(int, char**) {
     test ( "ABCDE", 5 );
     test ( "a", 1 );
 
@@ -59,4 +59,6 @@ int main () {
     static_assert ( sv.at(1) == 'B', "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.access/back.pass.cpp b/libcxx/test/std/strings/string.view/string.view.access/back.pass.cpp
index 8c8fd420d79f8107e4dcf17abbc94ea73cf87365..4505f1cf98180be8600fabec02a43af5ac95db43 100644
--- a/libcxx/test/std/strings/string.view/string.view.access/back.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.access/back.pass.cpp
@@ -24,7 +24,7 @@ bool test ( const CharT *s, size_t len ) {
     return &sv.back() == s + len - 1;
     }
 
-int main () {
+int main(int, char**) {
     assert ( test ( "ABCDE", 5 ));
     assert ( test ( "a", 1 ));
 
@@ -46,4 +46,6 @@ int main () {
     static_assert ( sv.back()  == 'B', "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.access/data.pass.cpp b/libcxx/test/std/strings/string.view/string.view.access/data.pass.cpp
index 85e02ceb0a75720d46e85ccba41511675b59d970..9ab83dfb2f53aea6bd3fa1f4866d10e5bb2a8317 100644
--- a/libcxx/test/std/strings/string.view/string.view.access/data.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.access/data.pass.cpp
@@ -27,7 +27,7 @@ void test ( const CharT *s, size_t len ) {
 #endif
     }
 
-int main () {
+int main(int, char**) {
     test ( "ABCDE", 5 );
     test ( "a", 1 );
 
@@ -50,4 +50,6 @@ int main () {
     static_assert( sv.data() == s, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.access/front.pass.cpp b/libcxx/test/std/strings/string.view/string.view.access/front.pass.cpp
index 6e73202d676323ce4528a8e032b9bf0cc9adcdb9..554ed1bab122857fc31079e17d197fb604dbbdbf 100644
--- a/libcxx/test/std/strings/string.view/string.view.access/front.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.access/front.pass.cpp
@@ -24,7 +24,7 @@ bool test ( const CharT *s, size_t len ) {
     return &sv.front() == s;
     }
 
-int main () {
+int main(int, char**) {
     assert ( test ( "ABCDE", 5 ));
     assert ( test ( "a", 1 ));
 
@@ -46,4 +46,6 @@ int main () {
     static_assert ( sv.front()  == 'A', "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.access/index.pass.cpp b/libcxx/test/std/strings/string.view/string.view.access/index.pass.cpp
index 87598dffe735cc381f196b06c7f0f63891515acb..33992de7c05004ff0f9dbcf8d7a7af7578e3a454 100644
--- a/libcxx/test/std/strings/string.view/string.view.access/index.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.access/index.pass.cpp
@@ -26,7 +26,7 @@ void test ( const CharT *s, size_t len ) {
         }
     }
 
-int main () {
+int main(int, char**) {
     test ( "ABCDE", 5 );
     test ( "a", 1 );
 
@@ -49,4 +49,6 @@ int main () {
     static_assert ( sv[1]  == 'B', "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.capacity/capacity.pass.cpp b/libcxx/test/std/strings/string.view/string.view.capacity/capacity.pass.cpp
index 93cc762832f2a7a34b2b1348efb86bb6c78907b4..025d905a3335672b532ffe3cfd68c13507d76e8b 100644
--- a/libcxx/test/std/strings/string.view/string.view.capacity/capacity.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.capacity/capacity.pass.cpp
@@ -62,7 +62,7 @@ void test2 ( const CharT *s, size_t len ) {
     }
 }
 
-int main () {
+int main(int, char**) {
     test1<std::string_view> ();
 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
     test1<std::u8string_view> ();
@@ -99,4 +99,6 @@ int main () {
     test2 ( U"a", 1 );
     test2 ( U"", 0 );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.capacity/empty.fail.cpp b/libcxx/test/std/strings/string.view/string.view.capacity/empty.fail.cpp
index 74bd413020d352ee0f210bb9ea8de7037ce3294f..1dd1dcf7cb5b2ace8c30a2113042cbefa89ced09 100644
--- a/libcxx/test/std/strings/string.view/string.view.capacity/empty.fail.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.capacity/empty.fail.cpp
@@ -20,8 +20,10 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     std::string_view c;
     c.empty();  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.comparison/opeq.string_view.pointer.pass.cpp b/libcxx/test/std/strings/string.view/string.view.comparison/opeq.string_view.pointer.pass.cpp
index bb6c34316521f3bc8095fbf6465959c8af29ab98..e771bd328a9f3d8e4dbec05ba1856436cba7b242 100644
--- a/libcxx/test/std/strings/string.view/string.view.comparison/opeq.string_view.pointer.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.comparison/opeq.string_view.pointer.pass.cpp
@@ -27,7 +27,7 @@ test(S lhs, const typename S::value_type* rhs, bool x)
     assert((rhs == lhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -65,4 +65,6 @@ int main()
     static_assert (!("abcde0" == sv2), "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.comparison/opeq.string_view.string.pass.cpp b/libcxx/test/std/strings/string.view/string.view.comparison/opeq.string_view.string.pass.cpp
index bb142b0b3c31b42b4917d072cdddc8c98bdc5360..d27d4c4458825c6da9acadf65d11c4152e1f73b0 100644
--- a/libcxx/test/std/strings/string.view/string.view.comparison/opeq.string_view.string.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.comparison/opeq.string_view.string.pass.cpp
@@ -25,7 +25,7 @@ test(const std::string &lhs, S rhs, bool x)
     assert((rhs == lhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -46,5 +46,7 @@ int main()
     test("abcdefghijklmnopqrst", S("abcdefghij"), false);
     test("abcdefghijklmnopqrst", S("abcdefghijklmnopqrst"), true);
     }
+
+  return 0;
 }
 
diff --git a/libcxx/test/std/strings/string.view/string.view.comparison/opeq.string_view.string_view.pass.cpp b/libcxx/test/std/strings/string.view/string.view.comparison/opeq.string_view.string_view.pass.cpp
index d7b113c120b124dcdd8b24682b72b43b747200e4..259711e3c5267c5899106bc703633a96eae7adbf 100644
--- a/libcxx/test/std/strings/string.view/string.view.comparison/opeq.string_view.string_view.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.comparison/opeq.string_view.string_view.pass.cpp
@@ -26,7 +26,7 @@ test(S lhs, S rhs, bool x)
     assert((rhs == lhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -58,4 +58,6 @@ int main()
     static_assert (!(sv1 == sv3), "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.comparison/opge.string_view.pointer.pass.cpp b/libcxx/test/std/strings/string.view/string.view.comparison/opge.string_view.pointer.pass.cpp
index 4f32425dc49fc2b6265f57d780f78c4612c0913b..5fa57eb394c50ab79c4ec9511d0fc41d6b80fb35 100644
--- a/libcxx/test/std/strings/string.view/string.view.comparison/opge.string_view.pointer.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.comparison/opge.string_view.pointer.pass.cpp
@@ -27,7 +27,7 @@ test(const typename S::value_type* lhs, const S& rhs, bool x, bool y)
     assert((rhs >= lhs) == y);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -68,4 +68,6 @@ int main()
     static_assert (  "abcde0" >= sv2, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.comparison/opge.string_view.string.pass.cpp b/libcxx/test/std/strings/string.view/string.view.comparison/opge.string_view.string.pass.cpp
index 9cbe389cd486fb00853498b1bd28a7f981dc53fb..dddaa390ed37918b0e5726b367f14c672b73ac1f 100644
--- a/libcxx/test/std/strings/string.view/string.view.comparison/opge.string_view.string.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.comparison/opge.string_view.string.pass.cpp
@@ -25,7 +25,7 @@ test(const S& lhs, const typename S::value_type* rhs, bool x, bool y)
     assert((rhs >= lhs) == y);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -46,4 +46,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), "abcdefghij", true, false);
     test(S("abcdefghijklmnopqrst"), "abcdefghijklmnopqrst", true, true);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.comparison/opge.string_view.string_view.pass.cpp b/libcxx/test/std/strings/string.view/string.view.comparison/opge.string_view.string_view.pass.cpp
index 81fee1f395350c8d971f57f8db567d070b3d09d6..d35bea575c85e7e2a2a1166883e124e171c372c1 100644
--- a/libcxx/test/std/strings/string.view/string.view.comparison/opge.string_view.string_view.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.comparison/opge.string_view.string_view.pass.cpp
@@ -26,7 +26,7 @@ test(const S& lhs, const S& rhs, bool x, bool y)
     assert((rhs >= lhs) == y);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -61,4 +61,6 @@ int main()
     static_assert (  sv2 >= sv1,  "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.comparison/opgt.string_view.pointer.pass.cpp b/libcxx/test/std/strings/string.view/string.view.comparison/opgt.string_view.pointer.pass.cpp
index c295645a9b721d52beef8bac798bc9259e2a9242..80dcc7b497b9a7bf4ccb7e59a97abe25233b1643 100644
--- a/libcxx/test/std/strings/string.view/string.view.comparison/opgt.string_view.pointer.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.comparison/opgt.string_view.pointer.pass.cpp
@@ -27,7 +27,7 @@ test(const typename S::value_type* lhs, const S& rhs, bool x, bool y)
     assert((rhs > lhs) == y);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -68,4 +68,6 @@ int main()
     static_assert (  "abcde0" > sv2, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.comparison/opgt.string_view.string.pass.cpp b/libcxx/test/std/strings/string.view/string.view.comparison/opgt.string_view.string.pass.cpp
index b07b6a7aca2ce4deacfa54b6f109641eb25e8937..84c9478bfc5d5279635454960e6c2c4284d388e1 100644
--- a/libcxx/test/std/strings/string.view/string.view.comparison/opgt.string_view.string.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.comparison/opgt.string_view.string.pass.cpp
@@ -25,7 +25,7 @@ test(const S& lhs, const typename S::value_type* rhs, bool x, bool y)
     assert((rhs > lhs) == y);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -46,4 +46,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), "abcdefghij", true, false);
     test(S("abcdefghijklmnopqrst"), "abcdefghijklmnopqrst", false, false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.comparison/opgt.string_view.string_view.pass.cpp b/libcxx/test/std/strings/string.view/string.view.comparison/opgt.string_view.string_view.pass.cpp
index 984f2c6a32ee89a4744bfe886eb7faa36f50ef54..ec31d5c2c1dbcf0554c88c65856e957c86f4389a 100644
--- a/libcxx/test/std/strings/string.view/string.view.comparison/opgt.string_view.string_view.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.comparison/opgt.string_view.string_view.pass.cpp
@@ -26,7 +26,7 @@ test(const S& lhs, const S& rhs, bool x, bool y)
     assert((rhs > lhs) == y);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -61,4 +61,6 @@ int main()
     static_assert (  sv2 > sv1, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.comparison/ople.string_view.pointer.pass.cpp b/libcxx/test/std/strings/string.view/string.view.comparison/ople.string_view.pointer.pass.cpp
index 81d0d167a000644fd98e906f621385aa4a4bcaba..4f582239a83ffa8cf6d837b045d3fece5827fa18 100644
--- a/libcxx/test/std/strings/string.view/string.view.comparison/ople.string_view.pointer.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.comparison/ople.string_view.pointer.pass.cpp
@@ -27,7 +27,7 @@ test(const typename S::value_type* lhs, const S& rhs, bool x, bool y)
     assert((rhs <= lhs) == y);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -68,4 +68,6 @@ int main()
     static_assert (!("abcde0" <= sv2), "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.comparison/ople.string_view.string.pass.cpp b/libcxx/test/std/strings/string.view/string.view.comparison/ople.string_view.string.pass.cpp
index 3cdb0215e48fc4ff388be8ad70d7181dfb8fb612..80e80757bf9f5b8c2965e49498ac7504ad0e8c8c 100644
--- a/libcxx/test/std/strings/string.view/string.view.comparison/ople.string_view.string.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.comparison/ople.string_view.string.pass.cpp
@@ -25,7 +25,7 @@ test(const S& lhs, const typename S::value_type* rhs, bool x, bool y)
     assert((rhs <= lhs) == y);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -46,4 +46,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), "abcdefghij", false, true);
     test(S("abcdefghijklmnopqrst"), "abcdefghijklmnopqrst", true, true);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.comparison/ople.string_view.string_view.pass.cpp b/libcxx/test/std/strings/string.view/string.view.comparison/ople.string_view.string_view.pass.cpp
index 3ec0222f66f083852c74001b0c580ba564469da6..b1c186124250bcf55514ddcba061b49f23b4f4ba 100644
--- a/libcxx/test/std/strings/string.view/string.view.comparison/ople.string_view.string_view.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.comparison/ople.string_view.string_view.pass.cpp
@@ -26,7 +26,7 @@ test(const S& lhs, const S& rhs, bool x, bool y)
     assert((rhs <= lhs) == y);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -61,4 +61,6 @@ int main()
     static_assert (!(sv2 <= sv1), "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.comparison/oplt.string_view.pointer.pass.cpp b/libcxx/test/std/strings/string.view/string.view.comparison/oplt.string_view.pointer.pass.cpp
index f8093c86a73fc24f2fcefae60ae8e700c42c867c..14bba2abfe6f4f3bf0ec859b030112a733f312a8 100644
--- a/libcxx/test/std/strings/string.view/string.view.comparison/oplt.string_view.pointer.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.comparison/oplt.string_view.pointer.pass.cpp
@@ -27,7 +27,7 @@ test(const typename S::value_type* lhs, const S& rhs, bool x, bool y)
     assert((rhs < lhs) == y);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -68,4 +68,6 @@ int main()
     static_assert (!("abcde0" < sv2), "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.comparison/oplt.string_view.string.pass.cpp b/libcxx/test/std/strings/string.view/string.view.comparison/oplt.string_view.string.pass.cpp
index e7341f17d1f74e23e3488206003b1a10da118c0e..f611bac7a846bd495b688e1b0bc9f09b99425b16 100644
--- a/libcxx/test/std/strings/string.view/string.view.comparison/oplt.string_view.string.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.comparison/oplt.string_view.string.pass.cpp
@@ -25,7 +25,7 @@ test(const S& lhs, const typename S::value_type* rhs, bool x, bool y)
     assert((rhs < lhs) == y);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -46,4 +46,6 @@ int main()
     test(S("abcdefghijklmnopqrst"), "abcdefghij", false, true);
     test(S("abcdefghijklmnopqrst"), "abcdefghijklmnopqrst", false, false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.comparison/oplt.string_view.string_view.pass.cpp b/libcxx/test/std/strings/string.view/string.view.comparison/oplt.string_view.string_view.pass.cpp
index a7e51f9af8c528f9ec51da43283c71de786d1c1f..f44e373619ad66d79090dd300d43331608b43222 100644
--- a/libcxx/test/std/strings/string.view/string.view.comparison/oplt.string_view.string_view.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.comparison/oplt.string_view.string_view.pass.cpp
@@ -26,7 +26,7 @@ test(const S& lhs, const S& rhs, bool x, bool y)
     assert((rhs < lhs) == y);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -61,4 +61,6 @@ int main()
     static_assert (!(sv2 < sv1), "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.comparison/opne.string_view.pointer.pass.cpp b/libcxx/test/std/strings/string.view/string.view.comparison/opne.string_view.pointer.pass.cpp
index 1531626a88463979776a9c2857403ebe064bf13c..6b8add831469d0254a51a890e00ecb70a6cc2d17 100644
--- a/libcxx/test/std/strings/string.view/string.view.comparison/opne.string_view.pointer.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.comparison/opne.string_view.pointer.pass.cpp
@@ -27,7 +27,7 @@ test(S lhs, const typename S::value_type* rhs, bool x)
     assert((rhs != lhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -66,4 +66,6 @@ int main()
     static_assert (  "abcde0" != sv2, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.comparison/opne.string_view.string.pass.cpp b/libcxx/test/std/strings/string.view/string.view.comparison/opne.string_view.string.pass.cpp
index 8e5539a80795c3cbfd4578e3bea363c38a7160dc..613eaf7b32f9ca1a54461cc9e0054da816d9bb55 100644
--- a/libcxx/test/std/strings/string.view/string.view.comparison/opne.string_view.string.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.comparison/opne.string_view.string.pass.cpp
@@ -25,7 +25,7 @@ test(const std::string &lhs, S rhs, bool x)
     assert((rhs != lhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -46,4 +46,6 @@ int main()
     test("abcdefghijklmnopqrst", S("abcdefghij"), true);
     test("abcdefghijklmnopqrst", S("abcdefghijklmnopqrst"), false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.comparison/opne.string_view.string_view.pass.cpp b/libcxx/test/std/strings/string.view/string.view.comparison/opne.string_view.string_view.pass.cpp
index 0e01e94db4334cde7c22f6ba73184c53186cb68c..90d153335ff064529aecd6a10c3eef72021da5ab 100644
--- a/libcxx/test/std/strings/string.view/string.view.comparison/opne.string_view.string_view.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.comparison/opne.string_view.string_view.pass.cpp
@@ -26,7 +26,7 @@ test(S lhs, S rhs, bool x)
     assert((rhs != lhs) == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -58,4 +58,6 @@ int main()
     static_assert (   sv1 != sv3,  "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.cons/assign.pass.cpp b/libcxx/test/std/strings/string.view/string.view.cons/assign.pass.cpp
index 8247c53c739022219b3e8345bb0ba592113a0c93..b2bf8ed7198b3c229f9489d1a6b746fdbec84380 100644
--- a/libcxx/test/std/strings/string.view/string.view.cons/assign.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.cons/assign.pass.cpp
@@ -29,7 +29,7 @@ bool test (T sv0)
     return sv0.size() == sv1.size() && sv0.data() == sv1.data();
     }
 
-int main () {
+int main(int, char**) {
 
     assert( test<std::string_view>    (  "1234"));
 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
@@ -54,4 +54,6 @@ int main () {
 #endif
     static_assert( test<std::wstring_view>   ({ L"abc", 3}), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.cons/default.pass.cpp b/libcxx/test/std/strings/string.view/string.view.cons/default.pass.cpp
index fe1fa97401210178f118ed7facfaf34734339f78..07a453b2369bcc29040f31374c53ef021f2da0b9 100644
--- a/libcxx/test/std/strings/string.view/string.view.cons/default.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.cons/default.pass.cpp
@@ -35,7 +35,7 @@ void test () {
     }
 }
 
-int main () {
+int main(int, char**) {
     test<std::string_view> ();
     test<std::u16string_view> ();
 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
@@ -44,4 +44,6 @@ int main () {
     test<std::u32string_view> ();
     test<std::wstring_view> ();
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.cons/from_literal.pass.cpp b/libcxx/test/std/strings/string.view/string.view.cons/from_literal.pass.cpp
index 7430f4ad6b53ece7637babb0e3e5e6e0534457c8..bcd83da74c67ae50a02df0dbec6520949294813b 100644
--- a/libcxx/test/std/strings/string.view/string.view.cons/from_literal.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.cons/from_literal.pass.cpp
@@ -39,7 +39,7 @@ void test ( const CharT *s ) {
     }
 
 
-int main () {
+int main(int, char**) {
 
     test ( "QBCDE" );
     test ( "A" );
@@ -65,4 +65,6 @@ int main () {
     static_assert ( sv1.size() == 5, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.cons/from_ptr_len.pass.cpp b/libcxx/test/std/strings/string.view/string.view.cons/from_ptr_len.pass.cpp
index 8ad0449aaca7c01962d6119f029c340bea2e61ca..92ae675a399ab50e417267e70243c8e03fd9b50c 100644
--- a/libcxx/test/std/strings/string.view/string.view.cons/from_ptr_len.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.cons/from_ptr_len.pass.cpp
@@ -31,7 +31,7 @@ void test ( const CharT *s, size_t sz ) {
     }
 }
 
-int main () {
+int main(int, char**) {
 
     test ( "QBCDE", 5 );
     test ( "QBCDE", 2 );
@@ -82,4 +82,6 @@ int main () {
     }
 #endif
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.cons/from_string.pass.cpp b/libcxx/test/std/strings/string.view/string.view.cons/from_string.pass.cpp
index 5e4a2d31908bdfcbd1fe837a5afb75e51f55c78e..2043d662a7a0a92c06254c3d85916035c6b7dca4 100644
--- a/libcxx/test/std/strings/string.view/string.view.cons/from_string.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.cons/from_string.pass.cpp
@@ -31,7 +31,7 @@ void test ( const std::basic_string<CharT, Traits> &str ) {
     assert ( sv1.data() == str.data());
 }
 
-int main () {
+int main(int, char**) {
 
     test ( std::string("QBCDE") );
     test ( std::string("") );
@@ -61,4 +61,6 @@ int main () {
     test ( std::basic_string<char, dummy_char_traits>("") );
     test ( std::basic_string<char, dummy_char_traits>() );
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.cons/from_string1.fail.cpp b/libcxx/test/std/strings/string.view/string.view.cons/from_string1.fail.cpp
index 343600625e8f96fb15380c164554fc3fc101f6a4..3c464d7fe3ebe0487c3ff34d91327088a233263c 100644
--- a/libcxx/test/std/strings/string.view/string.view.cons/from_string1.fail.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.cons/from_string1.fail.cpp
@@ -18,7 +18,7 @@
 
 struct dummy_char_traits : public std::char_traits<char> {};
 
-int main () {
+int main(int, char**) {
     using string_view = std::basic_string_view<char>;
     using string      = std::              basic_string     <char, dummy_char_traits>;
 
@@ -28,4 +28,6 @@ int main () {
     assert ( sv1.size() == s.size());
     assert ( sv1.data() == s.data());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.cons/from_string2.fail.cpp b/libcxx/test/std/strings/string.view/string.view.cons/from_string2.fail.cpp
index 2a0544defeac1afbb6e0ff7276c3474fd7b1139d..482d220013b0c6aa7965348c14faefd5923db9c3 100644
--- a/libcxx/test/std/strings/string.view/string.view.cons/from_string2.fail.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.cons/from_string2.fail.cpp
@@ -18,7 +18,7 @@
 
 struct dummy_char_traits : public std::char_traits<char> {};
 
-int main () {
+int main(int, char**) {
     using string_view = std::basic_string_view<char, dummy_char_traits>;
     using string      = std::              basic_string     <char>;
 
@@ -28,4 +28,6 @@ int main () {
     assert ( sv1.size() == s.size());
     assert ( sv1.data() == s.data());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.cons/implicit_deduction_guides.pass.cpp b/libcxx/test/std/strings/string.view/string.view.cons/implicit_deduction_guides.pass.cpp
index 3f1f562a4752a175c6cbd6711fc8db2ed77b2bf3..b95dca63dfdcfb61611adcfe086f9ff5886171dc 100644
--- a/libcxx/test/std/strings/string.view/string.view.cons/implicit_deduction_guides.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.cons/implicit_deduction_guides.pass.cpp
@@ -26,7 +26,7 @@
 // (2)  basic_string_view(const basic_string_view&)
 // (3)  basic_string_view(const CharT*, size_type)
 // (4)  basic_string_view(const CharT*)
-int main()
+int main(int, char**)
 {
   { // Testing (1)
     // Nothing TODO. Cannot deduce without any arguments.
@@ -61,4 +61,6 @@ int main()
     ASSERT_SAME_TYPE(decltype(w), std::wstring_view);
     assert(w == L"abcdef");
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.find/find_char_size.pass.cpp b/libcxx/test/std/strings/string.view/string.view.find/find_char_size.pass.cpp
index 8898d11afbff26bbd3a0ed018211e6d8ce3b4b9e..82173a93a88412dc976f924e43411646a3578115 100644
--- a/libcxx/test/std/strings/string.view/string.view.find/find_char_size.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.find/find_char_size.pass.cpp
@@ -35,7 +35,7 @@ test(const S& s, typename S::value_type c, typename S::size_type x)
         assert(0 <= x && x + 1 <= s.size());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -81,4 +81,6 @@ int main()
     static_assert (sv2.find( 'c', 4 ) == SV::npos, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.find/find_first_not_of_char_size.pass.cpp b/libcxx/test/std/strings/string.view/string.view.find/find_first_not_of_char_size.pass.cpp
index aae4048ac52826ca2a64300b06e879bbba8ce32b..4566adabfd3c8ade701282012f92fe7cbf5150b8 100644
--- a/libcxx/test/std/strings/string.view/string.view.find/find_first_not_of_char_size.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.find/find_first_not_of_char_size.pass.cpp
@@ -35,7 +35,7 @@ test(const S& s, typename S::value_type c, typename S::size_type x)
         assert(x < s.size());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -81,4 +81,6 @@ int main()
     static_assert (sv2.find_first_not_of( 'q', 5 ) == SV::npos, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.find/find_first_not_of_pointer_size.pass.cpp b/libcxx/test/std/strings/string.view/string.view.find/find_first_not_of_pointer_size.pass.cpp
index 0020e60b80181d3aad2a7e5843b78e6b9272beb1..17c3c5293f057ffb62e2977c41e8b74e45688645 100644
--- a/libcxx/test/std/strings/string.view/string.view.find/find_first_not_of_pointer_size.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.find/find_first_not_of_pointer_size.pass.cpp
@@ -141,7 +141,7 @@ void test1()
     test(S("pniotcfrhqsmgdkjbael"), "htaobedqikfplcgjsmrn", S::npos);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -162,4 +162,6 @@ int main()
     static_assert (sv2.find_first_not_of( "lecar", 0) == 1, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.find/find_first_not_of_pointer_size_size.pass.cpp b/libcxx/test/std/strings/string.view/string.view.find/find_first_not_of_pointer_size_size.pass.cpp
index 52f0696769394f35cc0b2d5089b84ff41125e646..707a7a96439bd879e678a2061c9ce15553ffddb6 100644
--- a/libcxx/test/std/strings/string.view/string.view.find/find_first_not_of_pointer_size_size.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.find/find_first_not_of_pointer_size_size.pass.cpp
@@ -366,7 +366,7 @@ void test3()
     test(S("hnbrcplsjfgiktoedmaq"), "qprlsfojamgndekthibc", 21, 20, S::npos);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -389,4 +389,6 @@ int main()
     static_assert (sv2.find_first_not_of( "lecar", 0, 5) == 1, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.find/find_first_not_of_string_view_size.pass.cpp b/libcxx/test/std/strings/string.view/string.view.find/find_first_not_of_string_view_size.pass.cpp
index 9378c6a0f45e25822c309067eeb6e0802c87a889..37445b578c72bdbb680c2ee9ba4f107356d8a945 100644
--- a/libcxx/test/std/strings/string.view/string.view.find/find_first_not_of_string_view_size.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.find/find_first_not_of_string_view_size.pass.cpp
@@ -137,11 +137,13 @@ void test1()
     test(S("pniotcfrhqsmgdkjbael"), S("htaobedqikfplcgjsmrn"), S::npos);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
     test0<S>();
     test1<S>();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.find/find_first_of_char_size.pass.cpp b/libcxx/test/std/strings/string.view/string.view.find/find_first_of_char_size.pass.cpp
index 6be6ddcd99c8e4186aaf6f1da06ff88b511a3cf8..d4916bec32fe39d58072d4277bb249bc1f7a2ded 100644
--- a/libcxx/test/std/strings/string.view/string.view.find/find_first_of_char_size.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.find/find_first_of_char_size.pass.cpp
@@ -35,7 +35,7 @@ test(const S& s, typename S::value_type c, typename S::size_type x)
         assert(x < s.size());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -79,4 +79,6 @@ int main()
     static_assert (sv2.find_first_of( 'e', 5 ) == SV::npos, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.find/find_first_of_pointer_size.pass.cpp b/libcxx/test/std/strings/string.view/string.view.find/find_first_of_pointer_size.pass.cpp
index bc3ea554bdedd8fa97d93f2135ff4e7939846255..7e43109afdd90812e086004cc18f43fd51c60b11 100644
--- a/libcxx/test/std/strings/string.view/string.view.find/find_first_of_pointer_size.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.find/find_first_of_pointer_size.pass.cpp
@@ -141,7 +141,7 @@ void test1()
     test(S("pniotcfrhqsmgdkjbael"), "htaobedqikfplcgjsmrn", 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -162,4 +162,6 @@ int main()
     static_assert (sv2.find_first_of( "lecar", 0) == 0, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.find/find_first_of_pointer_size_size.pass.cpp b/libcxx/test/std/strings/string.view/string.view.find/find_first_of_pointer_size_size.pass.cpp
index cd978436eb5becfb758751392842201e3d5faa62..165fb2362ae7ea9b959863d0c5e8f04437a13675 100644
--- a/libcxx/test/std/strings/string.view/string.view.find/find_first_of_pointer_size_size.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.find/find_first_of_pointer_size_size.pass.cpp
@@ -366,7 +366,7 @@ void test3()
     test(S("hnbrcplsjfgiktoedmaq"), "qprlsfojamgndekthibc", 21, 20, S::npos);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -389,4 +389,6 @@ int main()
     static_assert (sv2.find_first_of( "lecar", 0, 5) == 0, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.find/find_first_of_string_view_size.pass.cpp b/libcxx/test/std/strings/string.view/string.view.find/find_first_of_string_view_size.pass.cpp
index 545f4e51508d15236aabd6d8991da419c9d9cca8..c705f0266d86714e5468b0a4694d4f3d33ac3202 100644
--- a/libcxx/test/std/strings/string.view/string.view.find/find_first_of_string_view_size.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.find/find_first_of_string_view_size.pass.cpp
@@ -137,11 +137,13 @@ void test1()
     test(S("pniotcfrhqsmgdkjbael"), S("htaobedqikfplcgjsmrn"), 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
     test0<S>();
     test1<S>();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.find/find_last_not_of_char_size.pass.cpp b/libcxx/test/std/strings/string.view/string.view.find/find_last_not_of_char_size.pass.cpp
index 8d80557d4c554f50c406fc45f199ae96080be21a..0b6e6cfb0fa61921d66389d9da2fca9c3bbf989e 100644
--- a/libcxx/test/std/strings/string.view/string.view.find/find_last_not_of_char_size.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.find/find_last_not_of_char_size.pass.cpp
@@ -35,7 +35,7 @@ test(const S& s, typename S::value_type c, typename S::size_type x)
         assert(x < s.size());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -79,4 +79,6 @@ int main()
     static_assert (sv2.find_last_not_of( 'e', 5 ) == 3, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.find/find_last_not_of_pointer_size.pass.cpp b/libcxx/test/std/strings/string.view/string.view.find/find_last_not_of_pointer_size.pass.cpp
index f7daf3fa3bd27c2d61c4a06ef105d20af88822b1..fe17b779dd9a6a4501637e7e8b0e7d57bf6fecde 100644
--- a/libcxx/test/std/strings/string.view/string.view.find/find_last_not_of_pointer_size.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.find/find_last_not_of_pointer_size.pass.cpp
@@ -141,7 +141,7 @@ void test1()
     test(S("pniotcfrhqsmgdkjbael"), "htaobedqikfplcgjsmrn", S::npos);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -162,4 +162,6 @@ int main()
     static_assert (sv2.find_last_not_of( "lecar", 5) == 3, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.find/find_last_not_of_pointer_size_size.pass.cpp b/libcxx/test/std/strings/string.view/string.view.find/find_last_not_of_pointer_size_size.pass.cpp
index 8fd255395252da1f37a4bad7cfc608bfd7c4094e..11a5c27e8da5f2728f300f71d9a3efeb133937da 100644
--- a/libcxx/test/std/strings/string.view/string.view.find/find_last_not_of_pointer_size_size.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.find/find_last_not_of_pointer_size_size.pass.cpp
@@ -366,7 +366,7 @@ void test3()
     test(S("hnbrcplsjfgiktoedmaq"), "qprlsfojamgndekthibc", 21, 20, S::npos);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -389,4 +389,6 @@ int main()
     static_assert (sv2.find_last_not_of( "lecar", 5, 0) == 4, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.find/find_last_not_of_string_view_size.pass.cpp b/libcxx/test/std/strings/string.view/string.view.find/find_last_not_of_string_view_size.pass.cpp
index 06a31a1d6614e9c33ee5cd8867c511128943ca9a..e90e38c0d70859f0eae219ac238c819dbe1fa2cc 100644
--- a/libcxx/test/std/strings/string.view/string.view.find/find_last_not_of_string_view_size.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.find/find_last_not_of_string_view_size.pass.cpp
@@ -137,11 +137,13 @@ void test1()
     test(S("pniotcfrhqsmgdkjbael"), S("htaobedqikfplcgjsmrn"), S::npos);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
     test0<S>();
     test1<S>();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.find/find_last_of_char_size.pass.cpp b/libcxx/test/std/strings/string.view/string.view.find/find_last_of_char_size.pass.cpp
index 147e191b23773d66be1faad64ee05fd3818072a0..fdcf3173671cbc5a9d51911f03550f447b3bd271 100644
--- a/libcxx/test/std/strings/string.view/string.view.find/find_last_of_char_size.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.find/find_last_of_char_size.pass.cpp
@@ -35,7 +35,7 @@ test(const S& s, typename S::value_type c, typename S::size_type x)
         assert(x < s.size());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -79,4 +79,6 @@ int main()
     static_assert (sv2.find_last_of( 'e', 5 ) == 4, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.find/find_last_of_pointer_size.pass.cpp b/libcxx/test/std/strings/string.view/string.view.find/find_last_of_pointer_size.pass.cpp
index 5a12718314cee05a6920dd28d87ba1d22e995bd9..640f48375965f0421569a88f49096546ccc77245 100644
--- a/libcxx/test/std/strings/string.view/string.view.find/find_last_of_pointer_size.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.find/find_last_of_pointer_size.pass.cpp
@@ -141,7 +141,7 @@ void test1()
     test(S("pniotcfrhqsmgdkjbael"), "htaobedqikfplcgjsmrn", 19);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -162,4 +162,6 @@ int main()
     static_assert (sv2.find_last_of( "lecar", 5) == 4, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.find/find_last_of_pointer_size_size.pass.cpp b/libcxx/test/std/strings/string.view/string.view.find/find_last_of_pointer_size_size.pass.cpp
index 984029826912cc3f2c1698aa2d991d3c924b6e4b..e82c935b5ff732002142704ddcdf28bd791f1a08 100644
--- a/libcxx/test/std/strings/string.view/string.view.find/find_last_of_pointer_size_size.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.find/find_last_of_pointer_size_size.pass.cpp
@@ -366,7 +366,7 @@ void test3()
     test(S("hnbrcplsjfgiktoedmaq"), "qprlsfojamgndekthibc", 21, 20, 19);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -389,4 +389,6 @@ int main()
     static_assert (sv2.find_last_of( "lecar", 5, 5) == 4, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.find/find_last_of_string_view_size.pass.cpp b/libcxx/test/std/strings/string.view/string.view.find/find_last_of_string_view_size.pass.cpp
index 84b5a96df5d708fa677735c42c872e1f188c406b..02c1184eec8a7c2802ac0c6bc0ebfe47f17242b7 100644
--- a/libcxx/test/std/strings/string.view/string.view.find/find_last_of_string_view_size.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.find/find_last_of_string_view_size.pass.cpp
@@ -137,11 +137,13 @@ void test1()
     test(S("pniotcfrhqsmgdkjbael"), S("htaobedqikfplcgjsmrn"), 19);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
     test0<S>();
     test1<S>();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.find/find_pointer_size.pass.cpp b/libcxx/test/std/strings/string.view/string.view.find/find_pointer_size.pass.cpp
index 2be32a46a95fd02c2c2f12f52fa5dcdf873a0969..3f4fee54ef49b3a0655a6dcc9376311f65a54925 100644
--- a/libcxx/test/std/strings/string.view/string.view.find/find_pointer_size.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.find/find_pointer_size.pass.cpp
@@ -147,7 +147,7 @@ void test1()
     test(S("abcdeabcdeabcdeabcde"), "abcdeabcdeabcdeabcde", 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -168,4 +168,6 @@ int main()
     static_assert (sv2.find( "abcde", 1) == SV::npos, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.find/find_pointer_size_size.pass.cpp b/libcxx/test/std/strings/string.view/string.view.find/find_pointer_size_size.pass.cpp
index 0f7d295a4a56aa00981ea865b60377245ee7f02b..74caa6fea7b96bfe489b001315dec47c4f13b777 100644
--- a/libcxx/test/std/strings/string.view/string.view.find/find_pointer_size_size.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.find/find_pointer_size_size.pass.cpp
@@ -366,7 +366,7 @@ void test3()
     test(S("abcdeabcdeabcdeabcde"), "abcdeabcdeabcdeabcde", 21, 20, S::npos);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -390,4 +390,6 @@ int main()
     static_assert (sv2.find( "abcde", 0, 1 ) == 0, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.find/find_string_view_size.pass.cpp b/libcxx/test/std/strings/string.view/string.view.find/find_string_view_size.pass.cpp
index 0a5cec54eda7622ffed387127e2747db9ea4a59f..ed3b7c11c0240a586baec7c8dcb357e650c64511 100644
--- a/libcxx/test/std/strings/string.view/string.view.find/find_string_view_size.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.find/find_string_view_size.pass.cpp
@@ -140,7 +140,7 @@ void test1()
     test(S("abcdeabcdeabcdeabcde"), S("abcdeabcdeabcdeabcde"), 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -161,4 +161,6 @@ int main()
     static_assert (sv2.find(sv2, 1 ) == SV::npos, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.find/rfind_char_size.pass.cpp b/libcxx/test/std/strings/string.view/string.view.find/rfind_char_size.pass.cpp
index 62f50ed878611763079cc47e22753cb962794652..959bb05f8711529a929db12196044ac7a0e1d325 100644
--- a/libcxx/test/std/strings/string.view/string.view.find/rfind_char_size.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.find/rfind_char_size.pass.cpp
@@ -34,7 +34,7 @@ test(const S& s, typename S::value_type c, typename S::size_type x)
         assert(x + 1 <= s.size());
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -80,4 +80,6 @@ int main()
     static_assert (sv2.rfind( 'b', 4 ) == 1, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.find/rfind_pointer_size.pass.cpp b/libcxx/test/std/strings/string.view/string.view.find/rfind_pointer_size.pass.cpp
index 0ff2be51fc10ea2d5ca9538eb7aea7db89a89fe2..6010083ab1489174c700fa9e2683d853f524899c 100644
--- a/libcxx/test/std/strings/string.view/string.view.find/rfind_pointer_size.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.find/rfind_pointer_size.pass.cpp
@@ -147,7 +147,7 @@ void test1()
     test(S("abcdeabcdeabcdeabcde"), "abcdeabcdeabcdeabcde", 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -168,4 +168,6 @@ int main()
     static_assert (sv2.rfind( "abcde", 1) == 0, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.find/rfind_pointer_size_size.pass.cpp b/libcxx/test/std/strings/string.view/string.view.find/rfind_pointer_size_size.pass.cpp
index 18fd8437d7e96e3b1637e591ef2c40475477b17a..c3ca97e7ff97d500212aae5b1c3ce2623fb01950 100644
--- a/libcxx/test/std/strings/string.view/string.view.find/rfind_pointer_size_size.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.find/rfind_pointer_size_size.pass.cpp
@@ -365,7 +365,7 @@ void test3()
     test(S("abcdeabcdeabcdeabcde"), "abcdeabcdeabcdeabcde", 21, 20, 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -389,4 +389,6 @@ int main()
     static_assert (sv2.rfind( "abcde", 0, 1 ) == 0, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.find/rfind_string_view_size.pass.cpp b/libcxx/test/std/strings/string.view/string.view.find/rfind_string_view_size.pass.cpp
index dfc4a8361495476c9baa57a152bb2cc2d005984d..c4ceef331361b97fb240a35b07d7b8693621cb17 100644
--- a/libcxx/test/std/strings/string.view/string.view.find/rfind_string_view_size.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.find/rfind_string_view_size.pass.cpp
@@ -140,7 +140,7 @@ void test1()
     test(S("abcdeabcdeabcdeabcde"), S("abcdeabcdeabcdeabcde"), 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view S;
@@ -161,4 +161,6 @@ int main()
     static_assert (sv2.rfind(sv2, 1) == 0, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.hash/enabled_hashes.pass.cpp b/libcxx/test/std/strings/string.view/string.view.hash/enabled_hashes.pass.cpp
index 21dcbdf30390cd696ea790343d97f27c5f511d4a..d52f16303b6ab731c4b6aa1442112a56970ee7ac 100644
--- a/libcxx/test/std/strings/string.view/string.view.hash/enabled_hashes.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.hash/enabled_hashes.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "poisoned_hash_helper.hpp"
 
-int main() {
+int main(int, char**) {
   test_library_hash_specializations_available();
   {
     test_hash_enabled_for_type<std::string_view>();
@@ -30,4 +30,6 @@ int main() {
     test_hash_enabled_for_type<std::u32string_view>();
 #endif
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.hash/string_view.pass.cpp b/libcxx/test/std/strings/string.view/string.view.hash/string_view.pass.cpp
index 7cb7754038cccc6a2a2b5eeb9c2a8d7257468d53..0e296f2096dc00ffba627c226885d57f1d09fb0b 100644
--- a/libcxx/test/std/strings/string.view/string.view.hash/string_view.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.hash/string_view.pass.cpp
@@ -55,7 +55,7 @@ test()
     assert(sh(ss2) == h(s2));
 }
 
-int main()
+int main(int, char**)
 {
     test<std::string_view>();
 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
@@ -66,4 +66,6 @@ int main()
     test<std::u32string_view>();
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
     test<std::wstring_view>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.io/stream_insert.pass.cpp b/libcxx/test/std/strings/string.view/string.view.io/stream_insert.pass.cpp
index c721b2fcfe3b0dbcb99ee5c1587dd397b282beee..d4dcbdc6b0a7da970df058b166cb3f1c77dc013a 100644
--- a/libcxx/test/std/strings/string.view/string.view.io/stream_insert.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.io/stream_insert.pass.cpp
@@ -20,7 +20,7 @@
 using std::string_view;
 using std::wstring_view;
 
-int main()
+int main(int, char**)
 {
     {
         std::ostringstream out;
@@ -54,4 +54,6 @@ int main()
         assert(out.good());
         assert(L"   " + s == out.str());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.iterators/begin.pass.cpp b/libcxx/test/std/strings/string.view/string.view.iterators/begin.pass.cpp
index 0926f7f90220af0608993855b0af40fbde4a5e6d..ba700c8abbc162a1a23092c8b3eb362f337e9508 100644
--- a/libcxx/test/std/strings/string.view/string.view.iterators/begin.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.iterators/begin.pass.cpp
@@ -39,7 +39,7 @@ test(S s)
 }
 
 
-int main()
+int main(int, char**)
 {
     typedef std::string_view    string_view;
 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
@@ -90,4 +90,6 @@ int main()
     static_assert (   *wsv.cbegin() ==   wsv[0], "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.iterators/end.pass.cpp b/libcxx/test/std/strings/string.view/string.view.iterators/end.pass.cpp
index 1287cc201baa6f4b6c8acf7c35952220bdd11fbd..59c29e2dbdd9fac2fa35506e76caa77e189e70ab 100644
--- a/libcxx/test/std/strings/string.view/string.view.iterators/end.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.iterators/end.pass.cpp
@@ -48,7 +48,7 @@ test(S s)
 }
 
 
-int main()
+int main(int, char**)
 {
     typedef std::string_view    string_view;
 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
@@ -99,4 +99,6 @@ int main()
     static_assert (   wsv.begin() !=   wsv.cend(), "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.iterators/rbegin.pass.cpp b/libcxx/test/std/strings/string.view/string.view.iterators/rbegin.pass.cpp
index 43d1906c8f52f46c55ed98be19c4881f2e39fcd3..a57d7b454a3defc7470e48d368b71a7c40b6e454 100644
--- a/libcxx/test/std/strings/string.view/string.view.iterators/rbegin.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.iterators/rbegin.pass.cpp
@@ -40,7 +40,7 @@ test(S s)
 }
 
 
-int main()
+int main(int, char**)
 {
     typedef std::string_view    string_view;
 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
@@ -91,4 +91,6 @@ int main()
     static_assert (   *wsv.crbegin() ==   wsv[2], "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.iterators/rend.pass.cpp b/libcxx/test/std/strings/string.view/string.view.iterators/rend.pass.cpp
index a4eed7d97435077f5be6e708de11dda14f161894..e0db02c22f69fbbc34cfe5ac6e94c0a77bc0ff26 100644
--- a/libcxx/test/std/strings/string.view/string.view.iterators/rend.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.iterators/rend.pass.cpp
@@ -48,7 +48,7 @@ test(S s)
 }
 
 
-int main()
+int main(int, char**)
 {
     typedef std::string_view    string_view;
 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
@@ -99,4 +99,6 @@ int main()
     static_assert (   *--wsv.crend() ==   wsv[0], "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.modifiers/remove_prefix.pass.cpp b/libcxx/test/std/strings/string.view/string.view.modifiers/remove_prefix.pass.cpp
index 08fe79e8f8253e0a578f5a3a4f36ab25418ef551..2287ba6c80022273682454346e2fa53cde1a44b9 100644
--- a/libcxx/test/std/strings/string.view/string.view.modifiers/remove_prefix.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.modifiers/remove_prefix.pass.cpp
@@ -47,7 +47,7 @@ constexpr size_t test_ce ( size_t n, size_t k ) {
 }
 #endif
 
-int main () {
+int main(int, char**) {
     test ( "ABCDE", 5 );
     test ( "a", 1 );
     test ( "", 0 );
@@ -74,4 +74,6 @@ int main () {
     static_assert ( test_ce ( 9, 3 ) == 6, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.modifiers/remove_suffix.pass.cpp b/libcxx/test/std/strings/string.view/string.view.modifiers/remove_suffix.pass.cpp
index be9ca1e1fc97fa121dcab228744507479c1ca044..0636bcea9573dfdd175d946748b9caae742fea6c 100644
--- a/libcxx/test/std/strings/string.view/string.view.modifiers/remove_suffix.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.modifiers/remove_suffix.pass.cpp
@@ -47,7 +47,7 @@ constexpr size_t test_ce ( size_t n, size_t k ) {
 }
 #endif
 
-int main () {
+int main(int, char**) {
     test ( "ABCDE", 5 );
     test ( "a", 1 );
     test ( "", 0 );
@@ -74,4 +74,6 @@ int main () {
     static_assert ( test_ce ( 9, 3 ) == 6, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.modifiers/swap.pass.cpp b/libcxx/test/std/strings/string.view/string.view.modifiers/swap.pass.cpp
index 9b8eedd701bf76c66b29f6daa2effb7b420c68f0..2fc286e96a5b638ce9623a3b27d45b7832e19804 100644
--- a/libcxx/test/std/strings/string.view/string.view.modifiers/swap.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.modifiers/swap.pass.cpp
@@ -46,7 +46,7 @@ constexpr size_t test_ce ( size_t n, size_t k ) {
 #endif
 
 
-int main () {
+int main(int, char**) {
     test ( "ABCDE", 5 );
     test ( "a", 1 );
     test ( "", 0 );
@@ -72,4 +72,6 @@ int main () {
     static_assert ( test_ce (0, 1) == 1, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.nonmem/quoted.pass.cpp b/libcxx/test/std/strings/string.view/string.view.nonmem/quoted.pass.cpp
index f335da9585d87af534cf64d36b14fda569d7dc74..ecc24abf4be22d2f094e0133b5694e21affba55c 100644
--- a/libcxx/test/std/strings/string.view/string.view.nonmem/quoted.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.nonmem/quoted.pass.cpp
@@ -160,7 +160,7 @@ std::wstring unquote ( const wchar_t *p, wchar_t delim='"', wchar_t escape='\\'
     return s;
 }
 
-int main()
+int main(int, char**)
 {
     round_trip    (  "" );
     round_trip_ws (  "" );
@@ -207,7 +207,11 @@ int main()
 
     assert ( unquote (  "" ) ==  "" ); // nothing there
     assert ( unquote ( L"" ) == L"" ); // nothing there
-    }
+
+    return 0;
+}
 #else
-int main() {}
+int main(int, char**) {
+  return 0;
+}
 #endif
diff --git a/libcxx/test/std/strings/string.view/string.view.ops/compare.pointer.pass.cpp b/libcxx/test/std/strings/string.view/string.view.ops/compare.pointer.pass.cpp
index e9a854b34fa9eacd80a83747ac338a6a110060f5..0c04ce5e48bc404b45ea3ccf191c85f08782446c 100644
--- a/libcxx/test/std/strings/string.view/string.view.ops/compare.pointer.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.ops/compare.pointer.pass.cpp
@@ -32,7 +32,7 @@ test( const CharT *s1, const CharT *s2, int expected)
     test1 ( sv1, s2, expected );
 }
 
-int main()
+int main(int, char**)
 {
     {
     test("", "", 0);
@@ -123,4 +123,6 @@ int main()
     static_assert ( sv2.compare("abcde") == 0, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.ops/compare.pointer_size.pass.cpp b/libcxx/test/std/strings/string.view/string.view.ops/compare.pointer_size.pass.cpp
index 6f45222ff6c4e81fccd3475deaeda65037ed610a..974e687100d6dee2b5622ac62b9c2712d520fbe8 100644
--- a/libcxx/test/std/strings/string.view/string.view.ops/compare.pointer_size.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.ops/compare.pointer_size.pass.cpp
@@ -354,7 +354,7 @@ void test2()
 }
 
 
-int main()
+int main(int, char**)
 {
     test0();
     test1();
@@ -449,4 +449,6 @@ int main()
     static_assert ( sv2.compare(0, 6, "abcde") == 0, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.ops/compare.size_size_sv.pass.cpp b/libcxx/test/std/strings/string.view/string.view.ops/compare.size_size_sv.pass.cpp
index 452addc12dfdae0e1a22c0fef061bbfda7f9ceb4..73773fb26ee4fc07a07bb303df68b640e3f26747 100644
--- a/libcxx/test/std/strings/string.view/string.view.ops/compare.size_size_sv.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.ops/compare.size_size_sv.pass.cpp
@@ -354,7 +354,7 @@ void test2()
 }
 
 
-int main () {
+int main(int, char**) {
     test0();
     test1();
     test2();
@@ -398,4 +398,6 @@ int main () {
     static_assert ( sv1.compare(2, 4, sv2) == 1, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.ops/compare.size_size_sv_pointer_size.pass.cpp b/libcxx/test/std/strings/string.view/string.view.ops/compare.size_size_sv_pointer_size.pass.cpp
index d11f003313f77403869a4324f1c48edd93e3546b..df4e7394db982f128eebfda42fc21c4dab0a7a90 100644
--- a/libcxx/test/std/strings/string.view/string.view.ops/compare.size_size_sv_pointer_size.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.ops/compare.size_size_sv_pointer_size.pass.cpp
@@ -1291,7 +1291,7 @@ void test11()
     }
 
 
-int main () {
+int main(int, char**) {
     test0();
     test1();
     test2();
@@ -1349,4 +1349,6 @@ int main () {
     static_assert ( sv2.compare(0, 0, "abcde", 1, 0) == 0, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.ops/compare.size_size_sv_size_size.pass.cpp b/libcxx/test/std/strings/string.view/string.view.ops/compare.size_size_sv_size_size.pass.cpp
index 3f6e5787603b3f981415a5f30c5c030dd5521d63..56b6ec1f404c922e97fb823568bd28c9aff3ef70 100644
--- a/libcxx/test/std/strings/string.view/string.view.ops/compare.size_size_sv_size_size.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.ops/compare.size_size_sv_size_size.pass.cpp
@@ -5747,7 +5747,7 @@ void test54()
 }
 
 
-int main () {
+int main(int, char**) {
     test0();
     test1();
     test2();
@@ -5844,4 +5844,6 @@ int main () {
     static_assert ( sv1.compare(2, 4, "abcde", 3, 4) == -1, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.ops/compare.sv.pass.cpp b/libcxx/test/std/strings/string.view/string.view.ops/compare.sv.pass.cpp
index e65a7451f47cbf919133c1fa6762fb0870f5e17f..9c27f267459893da2fa87503b8846a687b35d7c9 100644
--- a/libcxx/test/std/strings/string.view/string.view.ops/compare.sv.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.ops/compare.sv.pass.cpp
@@ -34,7 +34,7 @@ void test ( const CharT *s1, const CharT  *s2, int expected ) {
     test1(sv1, sv2, expected);
 }
 
-int main () {
+int main(int, char**) {
 
     test("",                     "", 0);
     test("",                     "abcde", -5);
@@ -118,4 +118,6 @@ int main () {
     static_assert ( sv2.compare(sv3)  < 0, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.ops/copy.pass.cpp b/libcxx/test/std/strings/string.view/string.view.ops/copy.pass.cpp
index 3ec48b08c3310ee989131236cbf41fb536cc0fc3..e96650992cba608475a9bda5536d21bfd728da67 100644
--- a/libcxx/test/std/strings/string.view/string.view.ops/copy.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.ops/copy.pass.cpp
@@ -77,7 +77,7 @@ void test ( const CharT *s ) {
 
 }
 
-int main () {
+int main(int, char**) {
     test ( "ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE" );
     test ( "ABCDE");
     test ( "a" );
@@ -99,4 +99,6 @@ int main () {
     test ( U"a" );
     test ( U"" );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.ops/substr.pass.cpp b/libcxx/test/std/strings/string.view/string.view.ops/substr.pass.cpp
index 4391bb5134214d35fba0b40340f49af9ec71d24e..c2fd01f5724a2a095dce50ff7bf33d7e0aff2ba1 100644
--- a/libcxx/test/std/strings/string.view/string.view.ops/substr.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.ops/substr.pass.cpp
@@ -69,7 +69,7 @@ void test ( const CharT *s ) {
     test1(sv1, sv1.size() + 1, string_view_t::npos);
 }
 
-int main () {
+int main(int, char**) {
     test ( "ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE" );
     test ( "ABCDE");
     test ( "a" );
@@ -117,4 +117,6 @@ int main () {
     }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.synop/nothing_to_do.pass.cpp b/libcxx/test/std/strings/string.view/string.view.synop/nothing_to_do.pass.cpp
index 3f07051d03a6f2d3dcea2e39167d54d8885c0e06..45edec7f4b068815a761b79fb3fac8e87d7ae906 100644
--- a/libcxx/test/std/strings/string.view/string.view.synop/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.synop/nothing_to_do.pass.cpp
@@ -8,4 +8,6 @@
 
 #include <string_view>
 
-int main () {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/std/strings/string.view/string.view.template/ends_with.char.pass.cpp b/libcxx/test/std/strings/string.view/string.view.template/ends_with.char.pass.cpp
index c89fdb8e4e863321f0e33e181d90f61a97994651..c03733074275582e143e7cc7b837233efc70256a 100644
--- a/libcxx/test/std/strings/string.view/string.view.template/ends_with.char.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.template/ends_with.char.pass.cpp
@@ -17,7 +17,7 @@
 #include "test_macros.h"
 #include "constexpr_char_traits.hpp"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view SV;
@@ -43,4 +43,6 @@ int main()
     static_assert (!sv2.ends_with('x'), "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.template/ends_with.ptr.pass.cpp b/libcxx/test/std/strings/string.view/string.view.template/ends_with.ptr.pass.cpp
index 4ef1c8e2f9870db3037f347f5e9cf003cb543c97..64caf5cc0d5513d4002849e12c7eeeba56ce10b4 100644
--- a/libcxx/test/std/strings/string.view/string.view.template/ends_with.ptr.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.template/ends_with.ptr.pass.cpp
@@ -17,7 +17,7 @@
 #include "test_macros.h"
 #include "constexpr_char_traits.hpp"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view SV;
@@ -100,4 +100,6 @@ int main()
     static_assert ( svNot.ends_with("def"), "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.template/ends_with.string_view.pass.cpp b/libcxx/test/std/strings/string.view/string.view.template/ends_with.string_view.pass.cpp
index 2d115c104b4707c379415bd2bdae9d430f43e4f4..b5f67f8ddd128df3f74fbfed08f905cdb5da83aa 100644
--- a/libcxx/test/std/strings/string.view/string.view.template/ends_with.string_view.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.template/ends_with.string_view.pass.cpp
@@ -17,7 +17,7 @@
 #include "test_macros.h"
 #include "constexpr_char_traits.hpp"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view SV;
@@ -100,4 +100,6 @@ int main()
     static_assert ( svNot.ends_with(svNot), "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.template/nothing_to_do.pass.cpp b/libcxx/test/std/strings/string.view/string.view.template/nothing_to_do.pass.cpp
index 3f07051d03a6f2d3dcea2e39167d54d8885c0e06..45edec7f4b068815a761b79fb3fac8e87d7ae906 100644
--- a/libcxx/test/std/strings/string.view/string.view.template/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.template/nothing_to_do.pass.cpp
@@ -8,4 +8,6 @@
 
 #include <string_view>
 
-int main () {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/std/strings/string.view/string.view.template/starts_with.char.pass.cpp b/libcxx/test/std/strings/string.view/string.view.template/starts_with.char.pass.cpp
index d35222bbf87ebacb8944eb8aca2e68be0a3f3ce2..d43944fdec7ccc5bcd9474ce871feb4897b07964 100644
--- a/libcxx/test/std/strings/string.view/string.view.template/starts_with.char.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.template/starts_with.char.pass.cpp
@@ -17,7 +17,7 @@
 #include "test_macros.h"
 #include "constexpr_char_traits.hpp"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view SV;
@@ -43,4 +43,6 @@ int main()
     static_assert (!sv2.starts_with('x'), "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.template/starts_with.ptr.pass.cpp b/libcxx/test/std/strings/string.view/string.view.template/starts_with.ptr.pass.cpp
index a3ffde5c58486494be69cfe6143295be779a5197..ce651ec57e0e563c69b4758c66334d35b2fe9f98 100644
--- a/libcxx/test/std/strings/string.view/string.view.template/starts_with.ptr.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.template/starts_with.ptr.pass.cpp
@@ -17,7 +17,7 @@
 #include "test_macros.h"
 #include "constexpr_char_traits.hpp"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view SV;
@@ -100,4 +100,6 @@ int main()
     static_assert ( svNot.starts_with("def"), "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string.view.template/starts_with.string_view.pass.cpp b/libcxx/test/std/strings/string.view/string.view.template/starts_with.string_view.pass.cpp
index 5a5adbd8470eafc4e462fe9260b09173f1c3f977..3d184bae0eb5206f4233be5531f41738472fc4cc 100644
--- a/libcxx/test/std/strings/string.view/string.view.template/starts_with.string_view.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string.view.template/starts_with.string_view.pass.cpp
@@ -17,7 +17,7 @@
 #include "test_macros.h"
 #include "constexpr_char_traits.hpp"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::string_view SV;
@@ -100,4 +100,6 @@ int main()
     static_assert ( svNot.starts_with(svNot), "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string_view.literals/literal.pass.cpp b/libcxx/test/std/strings/string.view/string_view.literals/literal.pass.cpp
index c7d0e054df16c6b3692f3cf0647614b796702247..a8a1dff640450310e10e334f42cfe047c65fcadb 100644
--- a/libcxx/test/std/strings/string.view/string_view.literals/literal.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string_view.literals/literal.pass.cpp
@@ -23,7 +23,7 @@
     typedef std::string_view   u8string_view;
 #endif
 
-int main()
+int main(int, char**)
 {
     using namespace std::literals::string_view_literals;
 
@@ -69,4 +69,6 @@ int main()
     static_assert(noexcept( L"ABC"sv), "");
     static_assert(noexcept( u"ABC"sv), "");
     static_assert(noexcept( U"ABC"sv), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string_view.literals/literal1.fail.cpp b/libcxx/test/std/strings/string.view/string_view.literals/literal1.fail.cpp
index 05e66bf1eafceeb786579bc13beb2b0e1d5e6a60..5bf108bbef2271e36d605309ece049b378ba725a 100644
--- a/libcxx/test/std/strings/string.view/string_view.literals/literal1.fail.cpp
+++ b/libcxx/test/std/strings/string.view/string_view.literals/literal1.fail.cpp
@@ -14,9 +14,11 @@
 #include <string_view>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     using std::string_view;
 
     string_view foo  =   ""sv;  // should fail w/conversion operator not found
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string_view.literals/literal1.pass.cpp b/libcxx/test/std/strings/string.view/string_view.literals/literal1.pass.cpp
index 956d7d26a3208ae6c82ed8a528ae01d309c87de7..ba667e09cd1893c633dcc9454a336ecfd9fc44b9 100644
--- a/libcxx/test/std/strings/string.view/string_view.literals/literal1.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string_view.literals/literal1.pass.cpp
@@ -15,10 +15,12 @@
 #include <string_view>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     using namespace std::literals;
 
     std::string_view foo  =   ""sv;
     assert(foo.length() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string_view.literals/literal2.fail.cpp b/libcxx/test/std/strings/string.view/string_view.literals/literal2.fail.cpp
index 672201bb9a0a64df1fb702d6d99039323a1e73b7..2287e1ce92a445e207b5916c933035f73990468d 100644
--- a/libcxx/test/std/strings/string.view/string_view.literals/literal2.fail.cpp
+++ b/libcxx/test/std/strings/string.view/string_view.literals/literal2.fail.cpp
@@ -14,7 +14,9 @@
 #include <string_view>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::string_view foo  =   ""sv;  // should fail w/conversion operator not found
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string_view.literals/literal2.pass.cpp b/libcxx/test/std/strings/string.view/string_view.literals/literal2.pass.cpp
index 653738dc5a3afc706df8db66741134a7a0990d90..cb49280bfec59a78bf7bd67b82aa9a322f69b8cb 100644
--- a/libcxx/test/std/strings/string.view/string_view.literals/literal2.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string_view.literals/literal2.pass.cpp
@@ -15,10 +15,12 @@
 #include <string_view>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     using namespace std::literals::string_view_literals;
 
     std::string_view foo  =   ""sv;
     assert(foo.length() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/string_view.literals/literal3.pass.cpp b/libcxx/test/std/strings/string.view/string_view.literals/literal3.pass.cpp
index 814ec0cbdfe951f69898951081e3dc114b4243fc..710933dd95a48b72f22304f4d1e1736992737b80 100644
--- a/libcxx/test/std/strings/string.view/string_view.literals/literal3.pass.cpp
+++ b/libcxx/test/std/strings/string.view/string_view.literals/literal3.pass.cpp
@@ -15,10 +15,12 @@
 #include <string_view>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     using namespace std;
 
     string_view foo  =   ""sv;
     assert(foo.length() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/traits_mismatch.fail.cpp b/libcxx/test/std/strings/string.view/traits_mismatch.fail.cpp
index 6a32051a1c3f3d4bc3d34cea7fd78c89417c8f14..5cf3fa94793a38529cf0adb9da76ed8ec2fee39e 100644
--- a/libcxx/test/std/strings/string.view/traits_mismatch.fail.cpp
+++ b/libcxx/test/std/strings/string.view/traits_mismatch.fail.cpp
@@ -11,7 +11,9 @@
 
 #include <string_view>
 
-int main()
+int main(int, char**)
 {
     std::basic_string_view<char, std::char_traits<wchar_t>> s;
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/string.view/types.pass.cpp b/libcxx/test/std/strings/string.view/types.pass.cpp
index d8bb0f7373784240056d4b65af3d6a8b83ee5c97..d90f777babf69e59c6d5fd867c7917348cd93a1d 100644
--- a/libcxx/test/std/strings/string.view/types.pass.cpp
+++ b/libcxx/test/std/strings/string.view/types.pass.cpp
@@ -67,7 +67,7 @@ test()
     static_assert((std::is_same<typename S::reverse_iterator, typename S::const_reverse_iterator>::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     test<std::char_traits<char> >();
     test<std::char_traits<wchar_t> >();
@@ -76,4 +76,6 @@ int main()
 #endif
     static_assert((std::is_same<std::basic_string_view<char>::traits_type,
                                 std::char_traits<char> >::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/strings.erasure/erase.pass.cpp b/libcxx/test/std/strings/strings.erasure/erase.pass.cpp
index 250fe94a6f2804afc53e127895d4004da1c1126a..5013300d28b7467d5a7557445b2a0b0d8e9b6301 100644
--- a/libcxx/test/std/strings/strings.erasure/erase.pass.cpp
+++ b/libcxx/test/std/strings/strings.erasure/erase.pass.cpp
@@ -67,9 +67,11 @@ void test()
     test0(S("aba"), opt('c'), S("aba"));
 }
 
-int main()
+int main(int, char**)
 {
     test<std::string>();
     test<std::basic_string<char, std::char_traits<char>, min_allocator<char>>> ();
     test<std::basic_string<char, std::char_traits<char>, test_allocator<char>>> ();
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/strings.erasure/erase_if.pass.cpp b/libcxx/test/std/strings/strings.erasure/erase_if.pass.cpp
index 06b9cc2279ad260984124e4fcd80491380d177c6..5f2fb0117f84d4e83281485a78663167afcf5aab 100644
--- a/libcxx/test/std/strings/strings.erasure/erase_if.pass.cpp
+++ b/libcxx/test/std/strings/strings.erasure/erase_if.pass.cpp
@@ -67,9 +67,11 @@ void test()
     test0(S("aba"), True,   S(""));
 }
 
-int main()
+int main(int, char**)
 {
     test<std::string>();
     test<std::basic_string<char, std::char_traits<char>, min_allocator<char>>> ();
     test<std::basic_string<char, std::char_traits<char>, test_allocator<char>>> ();
+
+  return 0;
 }
diff --git a/libcxx/test/std/strings/strings.general/nothing_to_do.pass.cpp b/libcxx/test/std/strings/strings.general/nothing_to_do.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/std/strings/strings.general/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/strings/strings.general/nothing_to_do.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.async/async.fail.cpp b/libcxx/test/std/thread/futures/futures.async/async.fail.cpp
index f93c3ef20ffc973d282fd0848c6b54424534eeaf..3e7fb80e0e1fcdba039f96e10654df578a0cdf37 100644
--- a/libcxx/test/std/thread/futures/futures.async/async.fail.cpp
+++ b/libcxx/test/std/thread/futures/futures.async/async.fail.cpp
@@ -30,8 +30,10 @@
 
 int foo (int x) { return x; }
 
-int main ()
+int main(int, char**)
 {
     std::async(                    foo, 3); // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
     std::async(std::launch::async, foo, 3); // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.async/async.pass.cpp b/libcxx/test/std/thread/futures/futures.async/async.pass.cpp
index 1083cb47d444bc12db4c228e51cfdcb52f2a5b37..225b63ec8899a2103544c3dece2441bdee6b3dc8 100644
--- a/libcxx/test/std/thread/futures/futures.async/async.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.async/async.pass.cpp
@@ -102,7 +102,7 @@ void test(CheckLamdba&& getAndCheckFn, bool IsDeferred, Args&&... args) {
     }
 }
 
-int main()
+int main(int, char**)
 {
     // The default launch policy is implementation defined. libc++ defines
     // it to be std::launch::async.
@@ -151,4 +151,5 @@ int main()
         try { f.get(); assert (false); } catch ( int ) {}
     }
 #endif
+    return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.async/async_race.38682.pass.cpp b/libcxx/test/std/thread/futures/futures.async/async_race.38682.pass.cpp
index 6e115f00404caf2b7f57ecdb819b42c2dcadf487..826704a75d363d921e7955c000ee4ad60be36138 100644
--- a/libcxx/test/std/thread/futures/futures.async/async_race.38682.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.async/async_race.38682.pass.cpp
@@ -38,7 +38,7 @@ static int& worker_ref(int& i) { return i; }
 
 static void worker_void() { }
 
-int main() {
+int main(int, char**) {
   // future<T>
   {
     std::vector<int> const v{1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
@@ -65,4 +65,6 @@ int main() {
       fut.get();
     }
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.async/async_race.pass.cpp b/libcxx/test/std/thread/futures/futures.async/async_race.pass.cpp
index 62e09723e9eadebc573898cc13d034a2559e8ef1..9da57e38ae93f757fb7528b994ab54a4aeedf202 100644
--- a/libcxx/test/std/thread/futures/futures.async/async_race.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.async/async_race.pass.cpp
@@ -62,6 +62,8 @@ void test_each() {
     }
 }
 
-int main() {
+int main(int, char**) {
     for (int i=0; i < 25; ++i) test_each();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.errors/default_error_condition.pass.cpp b/libcxx/test/std/thread/futures/futures.errors/default_error_condition.pass.cpp
index 1676d4babaed0f0e8ba5d34329d25b8b2c2d4392..fbb7eb13d92fd62f8a08f69a5d19eb85f582fa2d 100644
--- a/libcxx/test/std/thread/futures/futures.errors/default_error_condition.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.errors/default_error_condition.pass.cpp
@@ -17,10 +17,12 @@
 #include <future>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::error_category& e_cat = std::future_category();
     std::error_condition e_cond = e_cat.default_error_condition(static_cast<int>(std::errc::not_a_directory));
     assert(e_cond.category() == e_cat);
     assert(e_cond.value() == static_cast<int>(std::errc::not_a_directory));
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.errors/equivalent_error_code_int.pass.cpp b/libcxx/test/std/thread/futures/futures.errors/equivalent_error_code_int.pass.cpp
index cb3f813936774b8fccd680f6153817ef62a70a00..3ba3410942dac23d8a20741b8b41b9e3bf58cd09 100644
--- a/libcxx/test/std/thread/futures/futures.errors/equivalent_error_code_int.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.errors/equivalent_error_code_int.pass.cpp
@@ -17,9 +17,11 @@
 #include <future>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::error_category& e_cat = std::future_category();
     assert(e_cat.equivalent(std::error_code(5, e_cat), 5));
     assert(!e_cat.equivalent(std::error_code(5, e_cat), 6));
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.errors/equivalent_int_error_condition.pass.cpp b/libcxx/test/std/thread/futures/futures.errors/equivalent_int_error_condition.pass.cpp
index f39de5b11f7045bf8a97ef65de09c494848dc59c..9d0e1cf31ba897ff18541f13e829ae93197947ad 100644
--- a/libcxx/test/std/thread/futures/futures.errors/equivalent_int_error_condition.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.errors/equivalent_int_error_condition.pass.cpp
@@ -17,10 +17,12 @@
 #include <future>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::error_category& e_cat = std::future_category();
     std::error_condition e_cond = e_cat.default_error_condition(5);
     assert(e_cat.equivalent(5, e_cond));
     assert(!e_cat.equivalent(6, e_cond));
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.errors/future_category.pass.cpp b/libcxx/test/std/thread/futures/futures.errors/future_category.pass.cpp
index e9e784c28d151a3492338d4dbb26f10f29f80ace..7b9d72344251aaabfdbac16f3841c2ed7d261a33 100644
--- a/libcxx/test/std/thread/futures/futures.errors/future_category.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.errors/future_category.pass.cpp
@@ -16,8 +16,10 @@
 #include <cstring>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::error_category& ec = std::future_category();
     assert(std::strcmp(ec.name(), "future") == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.errors/make_error_code.pass.cpp b/libcxx/test/std/thread/futures/futures.errors/make_error_code.pass.cpp
index 9e39585c8462731cd582953da30aeb77b056ee50..d9e50bf42d347942bf1cb2320499c2050393c461 100644
--- a/libcxx/test/std/thread/futures/futures.errors/make_error_code.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.errors/make_error_code.pass.cpp
@@ -17,11 +17,13 @@
 #include <future>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::error_code ec = make_error_code(std::future_errc::broken_promise);
         assert(ec.value() == static_cast<int>(std::future_errc::broken_promise));
         assert(ec.category() == std::future_category());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.errors/make_error_condition.pass.cpp b/libcxx/test/std/thread/futures/futures.errors/make_error_condition.pass.cpp
index f8cbbdedbded47ee528ddfb83f46d44b18e4bb07..d055591024657d871d1d5be22cc85eee97801e95 100644
--- a/libcxx/test/std/thread/futures/futures.errors/make_error_condition.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.errors/make_error_condition.pass.cpp
@@ -17,7 +17,7 @@
 #include <future>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         const std::error_condition ec1 =
@@ -26,4 +26,6 @@ int main()
                   static_cast<int>(std::future_errc::future_already_retrieved));
         assert(ec1.category() == std::future_category());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.future_error/code.pass.cpp b/libcxx/test/std/thread/futures/futures.future_error/code.pass.cpp
index 63769f018b7e2f97301af43005b3d5ee41397e79..53acba393fb8a6ee036398ebbc6fd498d73d14e1 100644
--- a/libcxx/test/std/thread/futures/futures.future_error/code.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.future_error/code.pass.cpp
@@ -21,7 +21,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::error_code ec = std::make_error_code(std::future_errc::broken_promise);
@@ -53,4 +53,6 @@ int main()
         assert(f.code() == std::make_error_code(std::future_errc::no_state));
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.future_error/types.pass.cpp b/libcxx/test/std/thread/futures/futures.future_error/types.pass.cpp
index 911f562e510fe0ce5a7ba78a82633d56695fd3e3..edf18ba5a9a026a2b02730d9eb41c8a1d78f02be 100644
--- a/libcxx/test/std/thread/futures/futures.future_error/types.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.future_error/types.pass.cpp
@@ -15,8 +15,10 @@
 #include <future>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_convertible<std::future_error*,
                                        std::logic_error*>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.future_error/what.pass.cpp b/libcxx/test/std/thread/futures/futures.future_error/what.pass.cpp
index bae25af1fab65d4272a0d604468dde390e5ff883..468aeb85bece0c42969d7cda00b5cea719e6684b 100644
--- a/libcxx/test/std/thread/futures/futures.future_error/what.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.future_error/what.pass.cpp
@@ -29,7 +29,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::future_error f(std::make_error_code(std::future_errc::broken_promise));
@@ -50,4 +50,6 @@ int main()
         LIBCPP_ASSERT(std::strcmp(f.what(), "Operation not permitted on an object without "
                       "an associated state.") == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.overview/future_errc.pass.cpp b/libcxx/test/std/thread/futures/futures.overview/future_errc.pass.cpp
index 383407d1328e7f6caf6cddc8ceda804ad2b7981a..d7840f45ce6bfd72b9a43ce65a2635af5ac07c4b 100644
--- a/libcxx/test/std/thread/futures/futures.overview/future_errc.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.overview/future_errc.pass.cpp
@@ -23,7 +23,7 @@
 
 #include <future>
 
-int main()
+int main(int, char**)
 {
     static_assert(std::future_errc::broken_promise != std::future_errc::future_already_retrieved, "");
     static_assert(std::future_errc::broken_promise != std::future_errc::promise_already_satisfied, "");
@@ -36,4 +36,6 @@ int main()
     static_assert(std::future_errc::future_already_retrieved != static_cast<std::future_errc>(0), "");
     static_assert(std::future_errc::promise_already_satisfied != static_cast<std::future_errc>(0), "");
     static_assert(std::future_errc::no_state != static_cast<std::future_errc>(0), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.overview/future_status.pass.cpp b/libcxx/test/std/thread/futures/futures.overview/future_status.pass.cpp
index 23c5bac06b7962ec8d7ecc6b1904c32f610e3fb3..ceff64f7ebb2d3451ba0725d8404c162796c14b3 100644
--- a/libcxx/test/std/thread/futures/futures.overview/future_status.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.overview/future_status.pass.cpp
@@ -19,9 +19,11 @@
 
 #include <future>
 
-int main()
+int main(int, char**)
 {
     static_assert(static_cast<int>(std::future_status::ready) == 0, "");
     static_assert(static_cast<int>(std::future_status::timeout) == 1, "");
     static_assert(static_cast<int>(std::future_status::deferred) == 2, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.overview/is_error_code_enum_future_errc.pass.cpp b/libcxx/test/std/thread/futures/futures.overview/is_error_code_enum_future_errc.pass.cpp
index f8a0d8a64928505ee8dd87fc6bf6c01be7e91ebe..c7e2c2aebaa352ce01e95b51e5d05105d880a396 100644
--- a/libcxx/test/std/thread/futures/futures.overview/is_error_code_enum_future_errc.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.overview/is_error_code_enum_future_errc.pass.cpp
@@ -15,10 +15,12 @@
 #include <future>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     static_assert(std::is_error_code_enum  <std::future_errc>::value, "");
 #if TEST_STD_VER > 14
     static_assert(std::is_error_code_enum_v<std::future_errc>, "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.overview/launch.pass.cpp b/libcxx/test/std/thread/futures/futures.overview/launch.pass.cpp
index 0ed166028c4ca86f64c8ccaff88e860c6dfcf0da..6d405b508eddffd7a716437ca29f4eba3b439479 100644
--- a/libcxx/test/std/thread/futures/futures.overview/launch.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.overview/launch.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 #ifdef _LIBCPP_HAS_NO_STRONG_ENUMS
    LIBCPP_STATIC_ASSERT(static_cast<int>(std::launch::any) ==
@@ -43,4 +43,6 @@ int main()
 #endif
     static_assert(static_cast<int>(std::launch::async) == 1, "");
     static_assert(static_cast<int>(std::launch::deferred) == 2, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.promise/alloc_ctor.pass.cpp b/libcxx/test/std/thread/futures/futures.promise/alloc_ctor.pass.cpp
index 1ad295220af7bd690064a455cad48739edec4c24..ece8b94a5632abc49ac27ba921ae08ff0b765814 100644
--- a/libcxx/test/std/thread/futures/futures.promise/alloc_ctor.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.promise/alloc_ctor.pass.cpp
@@ -22,7 +22,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     assert(test_alloc_base::alloc_count == 0);
     {
@@ -81,4 +81,6 @@ int main()
         std::future<void> f = p.get_future();
         assert(f.valid());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.promise/copy_assign.fail.cpp b/libcxx/test/std/thread/futures/futures.promise/copy_assign.fail.cpp
index 895ccf7fd5b4594fc662a48918939869de88f602..bf46a6847cbfcf557c289af85cc58aca72e84438 100644
--- a/libcxx/test/std/thread/futures/futures.promise/copy_assign.fail.cpp
+++ b/libcxx/test/std/thread/futures/futures.promise/copy_assign.fail.cpp
@@ -18,7 +18,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 #if TEST_STD_VER >= 11
     {
@@ -47,4 +47,6 @@ int main()
         p = p0; // expected-error {{'operator=' is a private member of 'std::__1::promise<void>'}}
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.promise/copy_ctor.fail.cpp b/libcxx/test/std/thread/futures/futures.promise/copy_ctor.fail.cpp
index 00af4af49ce0a84983bcb3562748890b821dcb03..8f90f3da7feeaf01ea9c1d6503ae8450f31c33db 100644
--- a/libcxx/test/std/thread/futures/futures.promise/copy_ctor.fail.cpp
+++ b/libcxx/test/std/thread/futures/futures.promise/copy_ctor.fail.cpp
@@ -18,7 +18,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 #if TEST_STD_VER >= 11
     {
@@ -47,4 +47,6 @@ int main()
         std::promise<void> p(p0); // expected-error {{calling a private constructor of class 'std::__1::promise<void>'}}
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.promise/default.pass.cpp b/libcxx/test/std/thread/futures/futures.promise/default.pass.cpp
index f0e3a786d6cd6390b31cd3b429dc6e87277bf4c7..600f99dd992fa13a1b9da3f13a5ca15dce821b52 100644
--- a/libcxx/test/std/thread/futures/futures.promise/default.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.promise/default.pass.cpp
@@ -18,7 +18,7 @@
 #include <future>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::promise<int> p;
@@ -35,4 +35,6 @@ int main()
         std::future<void> f = p.get_future();
         assert(f.valid());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.promise/dtor.pass.cpp b/libcxx/test/std/thread/futures/futures.promise/dtor.pass.cpp
index 4d3bd9cb98864bc3f3f92d734f474ad15a2da668..49c4b4685dbdfdb4ea7a27ba7ceb2dd525638ba5 100644
--- a/libcxx/test/std/thread/futures/futures.promise/dtor.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.promise/dtor.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -123,4 +123,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.promise/get_future.pass.cpp b/libcxx/test/std/thread/futures/futures.promise/get_future.pass.cpp
index 3805a96d04a154d00dc611cd110594e1bec48260..6385f6345debe5658f50fcf0cd68b7979f46f552 100644
--- a/libcxx/test/std/thread/futures/futures.promise/get_future.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.promise/get_future.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::promise<double> p;
@@ -56,4 +56,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.promise/move_assign.pass.cpp b/libcxx/test/std/thread/futures/futures.promise/move_assign.pass.cpp
index 46860fbe8406be8dca89cb03d519f991fae07b11..6592e0bb881d49978009021d4a7162d5293d5edc 100644
--- a/libcxx/test/std/thread/futures/futures.promise/move_assign.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.promise/move_assign.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_macros.h"
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     assert(test_alloc_base::alloc_count == 0);
     {
@@ -93,4 +93,6 @@ int main()
         assert(test_alloc_base::alloc_count == 1);
     }
     assert(test_alloc_base::alloc_count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.promise/move_ctor.pass.cpp b/libcxx/test/std/thread/futures/futures.promise/move_ctor.pass.cpp
index d119b188df1b9c00a6775d022e51a9e64b5d9632..1551420e9781cdb969ab10a06a0d886f6bfb6861 100644
--- a/libcxx/test/std/thread/futures/futures.promise/move_ctor.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.promise/move_ctor.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_macros.h"
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     assert(test_alloc_base::alloc_count == 0);
     {
@@ -87,4 +87,6 @@ int main()
 #endif
     }
     assert(test_alloc_base::alloc_count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.promise/set_exception.pass.cpp b/libcxx/test/std/thread/futures/futures.promise/set_exception.pass.cpp
index bb763e9ac511daed6f54257a3d016c2cb873e5c4..030620ad43f858dab185f1cb5923330d3cbde4a3 100644
--- a/libcxx/test/std/thread/futures/futures.promise/set_exception.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.promise/set_exception.pass.cpp
@@ -19,7 +19,7 @@
 #include <future>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -45,4 +45,6 @@ int main()
             assert(e.code() == make_error_code(std::future_errc::promise_already_satisfied));
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.promise/set_exception_at_thread_exit.pass.cpp b/libcxx/test/std/thread/futures/futures.promise/set_exception_at_thread_exit.pass.cpp
index c464d083bb553ea87d954b62fe5e8cf48f8ab300..a1a32882beeda7772ea0b4998aaff74abafcf0c3 100644
--- a/libcxx/test/std/thread/futures/futures.promise/set_exception_at_thread_exit.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.promise/set_exception_at_thread_exit.pass.cpp
@@ -24,7 +24,7 @@ void func(std::promise<int> p)
     p.set_exception_at_thread_exit(std::make_exception_ptr(3));
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -41,4 +41,6 @@ int main()
             assert(i == 3);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.promise/set_lvalue.pass.cpp b/libcxx/test/std/thread/futures/futures.promise/set_lvalue.pass.cpp
index 9b72e480371cd48aa93bf83c1d3a918c3ecc2e1e..db8bb5704c514c7ce419367ff8b615c16d87a7d5 100644
--- a/libcxx/test/std/thread/futures/futures.promise/set_lvalue.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.promise/set_lvalue.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int& T;
@@ -44,4 +44,6 @@ int main()
         }
 #endif
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.promise/set_lvalue_at_thread_exit.pass.cpp b/libcxx/test/std/thread/futures/futures.promise/set_lvalue_at_thread_exit.pass.cpp
index 0fa28031dd0519b916735f3d73d4a87080b884d4..9c3b09086b3daf0c57a8531441460958c636dd5e 100644
--- a/libcxx/test/std/thread/futures/futures.promise/set_lvalue_at_thread_exit.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.promise/set_lvalue_at_thread_exit.pass.cpp
@@ -27,7 +27,7 @@ void func(std::promise<int&> p)
     i = 4;
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::promise<int&> p;
@@ -35,4 +35,6 @@ int main()
         std::thread(func, std::move(p)).detach();
         assert(f.get() == 4);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.promise/set_rvalue.pass.cpp b/libcxx/test/std/thread/futures/futures.promise/set_rvalue.pass.cpp
index d0f2bda437816f612fcd0f67a54bbb3cd3dbc0ae..7f54baa8cec92fa1d2e134252f95466cddeca669 100644
--- a/libcxx/test/std/thread/futures/futures.promise/set_rvalue.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.promise/set_rvalue.pass.cpp
@@ -26,7 +26,7 @@ struct A
     A(A&&) {throw 9;}
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::unique_ptr<int> T;
@@ -60,4 +60,6 @@ int main()
             assert(j == 9);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.promise/set_rvalue_at_thread_exit.pass.cpp b/libcxx/test/std/thread/futures/futures.promise/set_rvalue_at_thread_exit.pass.cpp
index a5574238da5990de7fd0e56832f514a1dec919a2..bddd66135569967159015a8269888f12b15c0030 100644
--- a/libcxx/test/std/thread/futures/futures.promise/set_rvalue_at_thread_exit.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.promise/set_rvalue_at_thread_exit.pass.cpp
@@ -23,7 +23,7 @@ void func(std::promise<std::unique_ptr<int>> p)
     p.set_value_at_thread_exit(std::unique_ptr<int>(new int(5)));
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::promise<std::unique_ptr<int>> p;
@@ -31,4 +31,6 @@ int main()
         std::thread(func, std::move(p)).detach();
         assert(*f.get() == 5);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.promise/set_value_at_thread_exit_const.pass.cpp b/libcxx/test/std/thread/futures/futures.promise/set_value_at_thread_exit_const.pass.cpp
index 4760611771a2a41d54e520ebe710c7aceec03813..9258a001149adc123af088f6f1b9ac19c56be1c3 100644
--- a/libcxx/test/std/thread/futures/futures.promise/set_value_at_thread_exit_const.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.promise/set_value_at_thread_exit_const.pass.cpp
@@ -24,7 +24,7 @@ void func(std::promise<int> p)
     p.set_value_at_thread_exit(i);
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::promise<int> p;
@@ -32,4 +32,6 @@ int main()
         std::thread(func, std::move(p)).detach();
         assert(f.get() == 5);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.promise/set_value_at_thread_exit_void.pass.cpp b/libcxx/test/std/thread/futures/futures.promise/set_value_at_thread_exit_void.pass.cpp
index e2b8ae9a5da1b8031d9bc131715e6448e23d45e7..1a204421ee9295713585fab1e8620938d52366cd 100644
--- a/libcxx/test/std/thread/futures/futures.promise/set_value_at_thread_exit_void.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.promise/set_value_at_thread_exit_void.pass.cpp
@@ -27,7 +27,7 @@ void func(std::promise<void> p)
     i = 1;
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::promise<void> p;
@@ -36,4 +36,6 @@ int main()
         f.get();
         assert(i == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.promise/set_value_const.pass.cpp b/libcxx/test/std/thread/futures/futures.promise/set_value_const.pass.cpp
index 942481542f9f56e438eb7cc530070976360aed80..e58d2d24588a983553f0a0f1a939851eb1f3a303 100644
--- a/libcxx/test/std/thread/futures/futures.promise/set_value_const.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.promise/set_value_const.pass.cpp
@@ -28,7 +28,7 @@ struct A
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -68,4 +68,6 @@ int main()
         }
 #endif
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.promise/set_value_void.pass.cpp b/libcxx/test/std/thread/futures/futures.promise/set_value_void.pass.cpp
index 330d5b025089ef0f66545e520c08bcd9e8859a60..d505b3aabf4b97f0bd1f831a842260b3bdd944c2 100644
--- a/libcxx/test/std/thread/futures/futures.promise/set_value_void.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.promise/set_value_void.pass.cpp
@@ -19,7 +19,7 @@
 #include <future>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef void T;
@@ -37,4 +37,6 @@ int main()
             assert(e.code() == make_error_code(std::future_errc::promise_already_satisfied));
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.promise/swap.pass.cpp b/libcxx/test/std/thread/futures/futures.promise/swap.pass.cpp
index ec72f8794b0b4f17f5fbd5abe96297c9a6594f69..2b78b1d384b4bf552c59a4b2a52090d01bdd8a12 100644
--- a/libcxx/test/std/thread/futures/futures.promise/swap.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.promise/swap.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     assert(test_alloc_base::alloc_count == 0);
     {
@@ -81,4 +81,6 @@ int main()
         assert(test_alloc_base::alloc_count == 1);
     }
     assert(test_alloc_base::alloc_count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.promise/uses_allocator.pass.cpp b/libcxx/test/std/thread/futures/futures.promise/uses_allocator.pass.cpp
index 928ede9fb83d3404c58d437973757d5daa2dbad9..1a5028bce3ac217f8896ac9b646288345cd19db1 100644
--- a/libcxx/test/std/thread/futures/futures.promise/uses_allocator.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.promise/uses_allocator.pass.cpp
@@ -19,9 +19,11 @@
 #include <future>
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::uses_allocator<std::promise<int>, test_allocator<int> >::value), "");
     static_assert((std::uses_allocator<std::promise<int&>, test_allocator<int> >::value), "");
     static_assert((std::uses_allocator<std::promise<void>, test_allocator<void> >::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.shared_future/copy_assign.pass.cpp b/libcxx/test/std/thread/futures/futures.shared_future/copy_assign.pass.cpp
index 44c538c972e2634e86e2294fb94ea0cf81d0ce84..e5cc33a0c9493789f4fd8efd2520676b1b4b3a2e 100644
--- a/libcxx/test/std/thread/futures/futures.shared_future/copy_assign.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.shared_future/copy_assign.pass.cpp
@@ -21,7 +21,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -77,4 +77,6 @@ int main()
         assert(!f0.valid());
         assert(!f.valid());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.shared_future/copy_ctor.pass.cpp b/libcxx/test/std/thread/futures/futures.shared_future/copy_ctor.pass.cpp
index 2878c40d10ba37b7167a946992cdc9cdbbaba72a..01b5572e3f3b57b0bfe538622f447ad50d94ec23 100644
--- a/libcxx/test/std/thread/futures/futures.shared_future/copy_ctor.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.shared_future/copy_ctor.pass.cpp
@@ -21,7 +21,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -71,4 +71,6 @@ int main()
         assert(!f0.valid());
         assert(!f.valid());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.shared_future/ctor_future.pass.cpp b/libcxx/test/std/thread/futures/futures.shared_future/ctor_future.pass.cpp
index 10b84a4118ad99058b63ea79cbe828c166d5dae2..b75450cb9e97d02af01cf4aa4f8f02a9bfe6e40a 100644
--- a/libcxx/test/std/thread/futures/futures.shared_future/ctor_future.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.shared_future/ctor_future.pass.cpp
@@ -18,7 +18,7 @@
 #include <future>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -65,4 +65,6 @@ int main()
         assert(!f0.valid());
         assert(!f.valid());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.shared_future/default.pass.cpp b/libcxx/test/std/thread/futures/futures.shared_future/default.pass.cpp
index 2229ee58e3ddb5b2317137de372d5151915cb0b8..0387b97a70c8cce2072944389516fbdabe9ad145 100644
--- a/libcxx/test/std/thread/futures/futures.shared_future/default.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.shared_future/default.pass.cpp
@@ -17,7 +17,7 @@
 #include <future>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::shared_future<int> f;
@@ -31,4 +31,6 @@ int main()
         std::shared_future<void> f;
         assert(!f.valid());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.shared_future/dtor.pass.cpp b/libcxx/test/std/thread/futures/futures.shared_future/dtor.pass.cpp
index 964180b9898028f95bdd4d47c4bea56ac73fcdad..fe49c2208ee975e2e6d14dcfe81e6a4ba81c8ce8 100644
--- a/libcxx/test/std/thread/futures/futures.shared_future/dtor.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.shared_future/dtor.pass.cpp
@@ -21,7 +21,7 @@
 
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     assert(test_alloc_base::alloc_count == 0);
     {
@@ -66,4 +66,6 @@ int main()
         assert(f.valid());
     }
     assert(test_alloc_base::alloc_count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.shared_future/get.pass.cpp b/libcxx/test/std/thread/futures/futures.shared_future/get.pass.cpp
index b7767b379aca098ccab40cfb2bb4ce4e68a9480b..038ca71510f3f9d9787a022c05bc983794b1cb09 100644
--- a/libcxx/test/std/thread/futures/futures.shared_future/get.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.shared_future/get.pass.cpp
@@ -61,7 +61,7 @@ void func6(std::promise<void> p)
     p.set_exception(std::make_exception_ptr('c'));
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -150,4 +150,6 @@ int main()
         }
 #endif
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.shared_future/move_assign.pass.cpp b/libcxx/test/std/thread/futures/futures.shared_future/move_assign.pass.cpp
index b68ee6921de02fa8d9c3dceb037ef84ac71eab09..3940530528db764eadd4eb7b3c09b411ce021430 100644
--- a/libcxx/test/std/thread/futures/futures.shared_future/move_assign.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.shared_future/move_assign.pass.cpp
@@ -18,7 +18,7 @@
 #include <future>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -71,4 +71,6 @@ int main()
         assert(!f0.valid());
         assert(!f.valid());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.shared_future/move_ctor.pass.cpp b/libcxx/test/std/thread/futures/futures.shared_future/move_ctor.pass.cpp
index c2b52dc1b18d2f9f166b3b1de62f3bbe084bc5c3..e1d982d0ee10ae3753aee5d6884f09515940c42e 100644
--- a/libcxx/test/std/thread/futures/futures.shared_future/move_ctor.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.shared_future/move_ctor.pass.cpp
@@ -18,7 +18,7 @@
 #include <future>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -65,4 +65,6 @@ int main()
         assert(!f0.valid());
         assert(!f.valid());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.shared_future/wait.pass.cpp b/libcxx/test/std/thread/futures/futures.shared_future/wait.pass.cpp
index 11dc4ba3d139617c95435ba705fbfa4d6e690881..f78ca6bfc420598479c9344794fc6fb91ffa0ff6 100644
--- a/libcxx/test/std/thread/futures/futures.shared_future/wait.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.shared_future/wait.pass.cpp
@@ -39,7 +39,7 @@ void func5(std::promise<void> p)
     p.set_value();
 }
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::high_resolution_clock Clock;
     typedef std::chrono::duration<double, std::milli> ms;
@@ -85,4 +85,6 @@ int main()
         assert(f.valid());
         assert(t1-t0 < ms(5));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.shared_future/wait_for.pass.cpp b/libcxx/test/std/thread/futures/futures.shared_future/wait_for.pass.cpp
index 4fbd8ae7977016a3a136faa4842fab78494f8717..913127af3272a5b08609dab85e2ca6daede481af 100644
--- a/libcxx/test/std/thread/futures/futures.shared_future/wait_for.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.shared_future/wait_for.pass.cpp
@@ -43,7 +43,7 @@ void func5(std::promise<void> p)
     p.set_value();
 }
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::high_resolution_clock Clock;
     {
@@ -94,4 +94,6 @@ int main()
         assert(f.valid());
         assert(t1-t0 < ms(5));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.shared_future/wait_until.pass.cpp b/libcxx/test/std/thread/futures/futures.shared_future/wait_until.pass.cpp
index 02b0ce716e012615bc1bf5bd4229e463e6f66837..09787fedc3a63d53a4743e929f23716f3bbf8dc2 100644
--- a/libcxx/test/std/thread/futures/futures.shared_future/wait_until.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.shared_future/wait_until.pass.cpp
@@ -62,7 +62,7 @@ void func5(std::promise<void> p)
     set_worker_thread_state(WorkerThreadState::Exiting);
 }
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::high_resolution_clock Clock;
     {
@@ -128,4 +128,6 @@ int main()
         assert(f.valid());
         assert(t1-t0 < ms(5));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.state/nothing_to_do.pass.cpp b/libcxx/test/std/thread/futures/futures.state/nothing_to_do.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/std/thread/futures/futures.state/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.state/nothing_to_do.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.task/futures.task.members/assign_copy.fail.cpp b/libcxx/test/std/thread/futures/futures.task/futures.task.members/assign_copy.fail.cpp
index b14f2381a8dea97b4a66865f8091fee00b7f685d..a8b8581893dd5943d7ab97f4e67e35e7e1a97e73 100644
--- a/libcxx/test/std/thread/futures/futures.task/futures.task.members/assign_copy.fail.cpp
+++ b/libcxx/test/std/thread/futures/futures.task/futures.task.members/assign_copy.fail.cpp
@@ -17,10 +17,12 @@
 
 #include <future>
 
-int main()
+int main(int, char**)
 {
     {
         std::packaged_task<double(int, char)> p0, p;
         p = p0; // expected-error {{overload resolution selected deleted operator '='}}
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.task/futures.task.members/assign_move.pass.cpp b/libcxx/test/std/thread/futures/futures.task/futures.task.members/assign_move.pass.cpp
index 655a9d7f8daa7b5cff42ee23d5561aeb4890f4ef..9da7a96e241c175e82cc0ea04e7dd4d95cc10609 100644
--- a/libcxx/test/std/thread/futures/futures.task/futures.task.members/assign_move.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.task/futures.task.members/assign_move.pass.cpp
@@ -28,7 +28,7 @@ public:
     long operator()(long i, long j) const {return data_ + i + j;}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::packaged_task<double(int, char)> p0(A(5));
@@ -47,4 +47,6 @@ int main()
         assert(!p0.valid());
         assert(!p.valid());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.task/futures.task.members/ctor1.fail.cpp b/libcxx/test/std/thread/futures/futures.task/futures.task.members/ctor1.fail.cpp
index fbe3b55a81d758b00997da128bb747dbca82131e..ec081dc328ef8ed55dfaecadc9c0bba4cc8257f8 100644
--- a/libcxx/test/std/thread/futures/futures.task/futures.task.members/ctor1.fail.cpp
+++ b/libcxx/test/std/thread/futures/futures.task/futures.task.members/ctor1.fail.cpp
@@ -25,11 +25,13 @@ typedef std::packaged_task<A(int, char)> PT;
 typedef volatile std::packaged_task<A(int, char)> VPT;
 
 
-int main()
+int main(int, char**)
 {
     VPT init{};
     auto const& c_init = init;
     PT p1{init}; // expected-error {{no matching constructor}}
     PT p2{c_init}; // expected-error {{no matching constructor}}
     PT p3{std::move(init)}; // expected-error {{no matching constructor for initialization of 'PT' (aka 'packaged_task<A (int, char)>')}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.task/futures.task.members/ctor2.fail.cpp b/libcxx/test/std/thread/futures/futures.task/futures.task.members/ctor2.fail.cpp
index cae4e1afd45c5bebb2caab44a5da1ee5bb519786..76273a3eaa79d14017a8f6982c75c8a8d5be0209 100644
--- a/libcxx/test/std/thread/futures/futures.task/futures.task.members/ctor2.fail.cpp
+++ b/libcxx/test/std/thread/futures/futures.task/futures.task.members/ctor2.fail.cpp
@@ -26,8 +26,10 @@ struct A {};
 typedef std::packaged_task<A(int, char)> PT;
 typedef volatile std::packaged_task<A(int, char)> VPT;
 
-int main()
+int main(int, char**)
 {
     PT p { std::allocator_arg_t{}, test_allocator<A>{}, VPT {}}; // expected-error {{no matching constructor for initialization of 'PT' (aka 'packaged_task<A (int, char)>')}}
     // expected-note-re@future:* 1 {{candidate template ignored: {{(disabled by 'enable_if')|(requirement '.*' was not satisfied)}}}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.task/futures.task.members/ctor_copy.fail.cpp b/libcxx/test/std/thread/futures/futures.task/futures.task.members/ctor_copy.fail.cpp
index 6416df4de91b2e212af362cbbe3c2769a1420508..0816a1cc5b644d1f9429fac0f205a28c230d639b 100644
--- a/libcxx/test/std/thread/futures/futures.task/futures.task.members/ctor_copy.fail.cpp
+++ b/libcxx/test/std/thread/futures/futures.task/futures.task.members/ctor_copy.fail.cpp
@@ -18,10 +18,12 @@
 #include <future>
 
 
-int main()
+int main(int, char**)
 {
     {
         std::packaged_task<double(int, char)> p0;
         std::packaged_task<double(int, char)> p(p0); // expected-error {{call to deleted constructor of 'std::packaged_task<double (int, char)>'}}
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.task/futures.task.members/ctor_default.pass.cpp b/libcxx/test/std/thread/futures/futures.task/futures.task.members/ctor_default.pass.cpp
index 30c45eaab5163036ea00234532bb91330ef9d6a7..5472c717adce4167fb6e14a773135b51a56069eb 100644
--- a/libcxx/test/std/thread/futures/futures.task/futures.task.members/ctor_default.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.task/futures.task.members/ctor_default.pass.cpp
@@ -20,8 +20,10 @@
 
 struct A {};
 
-int main()
+int main(int, char**)
 {
     std::packaged_task<A(int, char)> p;
     assert(!p.valid());
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.task/futures.task.members/ctor_func.pass.cpp b/libcxx/test/std/thread/futures/futures.task/futures.task.members/ctor_func.pass.cpp
index 3da276ba8c3f4eb1a7b8892ae750543122080dc0..20ee8b4b4d2d696d1f295db8cd38875824f62144 100644
--- a/libcxx/test/std/thread/futures/futures.task/futures.task.members/ctor_func.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.task/futures.task.members/ctor_func.pass.cpp
@@ -39,7 +39,7 @@ int A::n_copies = 0;
 
 int func(int i) { return i; }
 
-int main()
+int main(int, char**)
 {
     {
         std::packaged_task<double(int, char)> p(A(5));
@@ -76,4 +76,6 @@ int main()
         p(4);
         assert(f.get() == 4);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.task/futures.task.members/ctor_func_alloc.pass.cpp b/libcxx/test/std/thread/futures/futures.task/futures.task.members/ctor_func_alloc.pass.cpp
index 334ed8f9806caaf5fb1bd30da980b3774b72aeeb..766987ce0dfc34f822853b8cf51890cc796f7315 100644
--- a/libcxx/test/std/thread/futures/futures.task/futures.task.members/ctor_func_alloc.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.task/futures.task.members/ctor_func_alloc.pass.cpp
@@ -44,7 +44,7 @@ int A::n_copies = 0;
 
 int func(int i) { return i; }
 
-int main()
+int main(int, char**)
 {
     {
         std::packaged_task<double(int, char)> p(std::allocator_arg,
@@ -123,4 +123,6 @@ int main()
     }
     A::n_copies = 0;
     A::n_moves  = 0;
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.task/futures.task.members/ctor_move.pass.cpp b/libcxx/test/std/thread/futures/futures.task/futures.task.members/ctor_move.pass.cpp
index e2e44473ef275001c9bb100b658e7af6f8a56731..c517182d3ad78c7c6920d4a6cc5cb73a0dbdb70c 100644
--- a/libcxx/test/std/thread/futures/futures.task/futures.task.members/ctor_move.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.task/futures.task.members/ctor_move.pass.cpp
@@ -28,7 +28,7 @@ public:
     long operator()(long i, long j) const {return data_ + i + j;}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::packaged_task<double(int, char)> p0(A(5));
@@ -45,4 +45,6 @@ int main()
         assert(!p0.valid());
         assert(!p.valid());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.task/futures.task.members/dtor.pass.cpp b/libcxx/test/std/thread/futures/futures.task/futures.task.members/dtor.pass.cpp
index e910d7c4ce8e016d05e75ba6e113bcdbd081edde..3b794b7f6c9e611c24964801efc30128be4da7dd 100644
--- a/libcxx/test/std/thread/futures/futures.task/futures.task.members/dtor.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.task/futures.task.members/dtor.pass.cpp
@@ -39,7 +39,7 @@ void func2(std::packaged_task<double(int, char)> p)
     p(3, 'a');
 }
 
-int main()
+int main(int, char**)
 {
 #ifndef TEST_HAS_NO_EXCEPTIONS
     {
@@ -64,4 +64,6 @@ int main()
         std::thread(func2, std::move(p)).detach();
         assert(f.get() == 105.0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.task/futures.task.members/get_future.pass.cpp b/libcxx/test/std/thread/futures/futures.task/futures.task.members/get_future.pass.cpp
index a4c9c7af490ae240f58b4f0871780fef295e42e7..8713db0a7e8d4e2b8a7a3c860a0985c73ff85bb5 100644
--- a/libcxx/test/std/thread/futures/futures.task/futures.task.members/get_future.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.task/futures.task.members/get_future.pass.cpp
@@ -30,7 +30,7 @@ public:
     long operator()(long i, long j) const {return data_ + i + j;}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::packaged_task<double(int, char)> p(A(5));
@@ -65,4 +65,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.task/futures.task.members/make_ready_at_thread_exit.pass.cpp b/libcxx/test/std/thread/futures/futures.task/futures.task.members/make_ready_at_thread_exit.pass.cpp
index 21a567ca0bd3b57b1c406c9f887d2ac9fe0ac6af..470099522985bc49580335b675539540d83d1d06 100644
--- a/libcxx/test/std/thread/futures/futures.task/futures.task.members/make_ready_at_thread_exit.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.task/futures.task.members/make_ready_at_thread_exit.pass.cpp
@@ -80,7 +80,7 @@ void func3(std::packaged_task<double(int, char)> p)
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::packaged_task<double(int, char)> p(A(5));
@@ -115,4 +115,6 @@ int main()
         t.join();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.task/futures.task.members/operator.pass.cpp b/libcxx/test/std/thread/futures/futures.task/futures.task.members/operator.pass.cpp
index e148ddfc97a91294186ee0d7a4eca144ab723e96..536888057a99f7c9722f7d2909b1bdc0af87917b 100644
--- a/libcxx/test/std/thread/futures/futures.task/futures.task.members/operator.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.task/futures.task.members/operator.pass.cpp
@@ -80,7 +80,7 @@ void func3(std::packaged_task<double(int, char)> p)
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::packaged_task<double(int, char)> p(A(5));
@@ -116,4 +116,6 @@ int main()
         t.join();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.task/futures.task.members/reset.pass.cpp b/libcxx/test/std/thread/futures/futures.task/futures.task.members/reset.pass.cpp
index 7e4dd5522ca30183ab0bb9683c93e2e94308e311..e9f59cdfe3cc39c71a9a1c7826b4e9f71ea0cdcb 100644
--- a/libcxx/test/std/thread/futures/futures.task/futures.task.members/reset.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.task/futures.task.members/reset.pass.cpp
@@ -33,7 +33,7 @@ public:
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::packaged_task<double(int, char)> p(A(5));
@@ -59,4 +59,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.task/futures.task.members/swap.pass.cpp b/libcxx/test/std/thread/futures/futures.task/futures.task.members/swap.pass.cpp
index 22e680f2acaa6ff5f87571b7b038e35319188d30..2cd97900df7219cbae2d259891229addb2879ef8 100644
--- a/libcxx/test/std/thread/futures/futures.task/futures.task.members/swap.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.task/futures.task.members/swap.pass.cpp
@@ -28,7 +28,7 @@ public:
     long operator()(long i, long j) const {return data_ + i + j;}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::packaged_task<double(int, char)> p0(A(5));
@@ -47,4 +47,6 @@ int main()
         assert(!p0.valid());
         assert(!p.valid());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.task/futures.task.nonmembers/swap.pass.cpp b/libcxx/test/std/thread/futures/futures.task/futures.task.nonmembers/swap.pass.cpp
index b344398fe52ba8d0891ebb5ea697ba8ce760c096..8c1c19eca62085ecfed4deb36c01bca32623d076 100644
--- a/libcxx/test/std/thread/futures/futures.task/futures.task.nonmembers/swap.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.task/futures.task.nonmembers/swap.pass.cpp
@@ -30,7 +30,7 @@ public:
     long operator()(long i, long j) const {return data_ + i + j;}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::packaged_task<double(int, char)> p0(A(5));
@@ -49,4 +49,6 @@ int main()
         assert(!p0.valid());
         assert(!p.valid());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.task/futures.task.nonmembers/uses_allocator.pass.cpp b/libcxx/test/std/thread/futures/futures.task/futures.task.nonmembers/uses_allocator.pass.cpp
index 24727b5d32bdeda7c663fca4571d5a32f57810ca..5257a7008cd2dd9192e05b5123fbf130dc06f4ce 100644
--- a/libcxx/test/std/thread/futures/futures.task/futures.task.nonmembers/uses_allocator.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.task/futures.task.nonmembers/uses_allocator.pass.cpp
@@ -27,7 +27,9 @@
 #include <future>
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::uses_allocator<std::packaged_task<double(int, char)>, test_allocator<int> >::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.unique_future/copy_assign.fail.cpp b/libcxx/test/std/thread/futures/futures.unique_future/copy_assign.fail.cpp
index 63e92f0214036e2228d12fda7df0565263ee5528..3a1a4d6be6c1ed5e2e85932b64039ec69a454cae 100644
--- a/libcxx/test/std/thread/futures/futures.unique_future/copy_assign.fail.cpp
+++ b/libcxx/test/std/thread/futures/futures.unique_future/copy_assign.fail.cpp
@@ -18,7 +18,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 #if TEST_STD_VER >= 11
     {
@@ -47,4 +47,6 @@ int main()
         f = f0; // expected-error {{'operator=' is a private member of 'std::__1::future<void>'}}
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.unique_future/copy_ctor.fail.cpp b/libcxx/test/std/thread/futures/futures.unique_future/copy_ctor.fail.cpp
index 0d1a5884b933a4a8bfef9960509e3bd9357568d2..4a8b98c1982e50a13a8ae93e6a0ef804bb455069 100644
--- a/libcxx/test/std/thread/futures/futures.unique_future/copy_ctor.fail.cpp
+++ b/libcxx/test/std/thread/futures/futures.unique_future/copy_ctor.fail.cpp
@@ -18,7 +18,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 #if TEST_STD_VER >= 11
     {
@@ -47,4 +47,6 @@ int main()
         std::future<void> f = f0; // expected-error {{calling a private constructor of class 'std::__1::future<void>'}}
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.unique_future/default.pass.cpp b/libcxx/test/std/thread/futures/futures.unique_future/default.pass.cpp
index 0f11aa3340729ff461edc7fe0ff86ab1d4d99f87..60ef645e3c955c8925a8bdd2f3181b64e3a95657 100644
--- a/libcxx/test/std/thread/futures/futures.unique_future/default.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.unique_future/default.pass.cpp
@@ -17,7 +17,7 @@
 #include <future>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::future<int> f;
@@ -31,4 +31,6 @@ int main()
         std::future<void> f;
         assert(!f.valid());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.unique_future/dtor.pass.cpp b/libcxx/test/std/thread/futures/futures.unique_future/dtor.pass.cpp
index 4105d3f906367668501441107aff838cd3502dcf..ec27219daffbfe4c2a364497a88684dda38c3b97 100644
--- a/libcxx/test/std/thread/futures/futures.unique_future/dtor.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.unique_future/dtor.pass.cpp
@@ -21,7 +21,7 @@
 
 #include "test_allocator.h"
 
-int main()
+int main(int, char**)
 {
     assert(test_alloc_base::alloc_count == 0);
     {
@@ -66,4 +66,6 @@ int main()
         assert(f.valid());
     }
     assert(test_alloc_base::alloc_count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.unique_future/get.pass.cpp b/libcxx/test/std/thread/futures/futures.unique_future/get.pass.cpp
index 3d50d896a89382401b35a63946b56c22a32be931..2e3e32648977917c8720e0b606a8c2af56e03974 100644
--- a/libcxx/test/std/thread/futures/futures.unique_future/get.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.unique_future/get.pass.cpp
@@ -61,7 +61,7 @@ void func6(std::promise<void> p)
     p.set_exception(std::make_exception_ptr('c'));
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -150,4 +150,6 @@ int main()
         }
 #endif
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.unique_future/move_assign.pass.cpp b/libcxx/test/std/thread/futures/futures.unique_future/move_assign.pass.cpp
index 7d2ad6218a293ee7c9903e3432c947e7d06b6bb6..b0f0e2b5c54b2e17e40ca58ec7791b923606b6a6 100644
--- a/libcxx/test/std/thread/futures/futures.unique_future/move_assign.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.unique_future/move_assign.pass.cpp
@@ -17,7 +17,7 @@
 #include <future>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -70,4 +70,6 @@ int main()
         assert(!f0.valid());
         assert(!f.valid());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.unique_future/move_ctor.pass.cpp b/libcxx/test/std/thread/futures/futures.unique_future/move_ctor.pass.cpp
index 0b0e4913cf5247108c2720557863a0c7bea8de59..aca5dda64f59b070a488a5f311cd713494081d18 100644
--- a/libcxx/test/std/thread/futures/futures.unique_future/move_ctor.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.unique_future/move_ctor.pass.cpp
@@ -17,7 +17,7 @@
 #include <future>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -64,4 +64,6 @@ int main()
         assert(!f0.valid());
         assert(!f.valid());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.unique_future/share.pass.cpp b/libcxx/test/std/thread/futures/futures.unique_future/share.pass.cpp
index 392a43a47634410b4d6a66b6c9ecb492d14384f5..979f93cccf7b7f91cac71d98ea49fe12719b21df 100644
--- a/libcxx/test/std/thread/futures/futures.unique_future/share.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.unique_future/share.pass.cpp
@@ -18,7 +18,7 @@
 #include <future>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -71,4 +71,6 @@ int main()
         assert(!f0.valid());
         assert(!f.valid());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.unique_future/wait.pass.cpp b/libcxx/test/std/thread/futures/futures.unique_future/wait.pass.cpp
index 0ec23f27ed0f6cbeeb7e1ee508f3c0f523336663..11fc80868f6d443648ee3e829e0d09f47c1da7c3 100644
--- a/libcxx/test/std/thread/futures/futures.unique_future/wait.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.unique_future/wait.pass.cpp
@@ -39,7 +39,7 @@ void func5(std::promise<void> p)
     p.set_value();
 }
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::high_resolution_clock Clock;
     typedef std::chrono::duration<double, std::milli> ms;
@@ -85,4 +85,6 @@ int main()
         assert(f.valid());
         assert(t1-t0 < ms(5));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.unique_future/wait_for.pass.cpp b/libcxx/test/std/thread/futures/futures.unique_future/wait_for.pass.cpp
index 5b8a01aaf16beaeeec283bea83d35c6ead5204d4..91f962fd18f8165ea3bfb4e5a4e765fbe1281287 100644
--- a/libcxx/test/std/thread/futures/futures.unique_future/wait_for.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.unique_future/wait_for.pass.cpp
@@ -43,7 +43,7 @@ void func5(std::promise<void> p)
     p.set_value();
 }
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::high_resolution_clock Clock;
     {
@@ -94,4 +94,6 @@ int main()
         assert(f.valid());
         assert(t1-t0 < ms(50));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/futures/futures.unique_future/wait_until.pass.cpp b/libcxx/test/std/thread/futures/futures.unique_future/wait_until.pass.cpp
index 79da1c0e3ee5e5cdb68dd1ee62f2cdfe64a649b1..28d9b638aed2df611584a0e39ac76ad102d5c9ec 100644
--- a/libcxx/test/std/thread/futures/futures.unique_future/wait_until.pass.cpp
+++ b/libcxx/test/std/thread/futures/futures.unique_future/wait_until.pass.cpp
@@ -60,7 +60,7 @@ void func5(std::promise<void> p)
     set_worker_thread_state(WorkerThreadState::Exiting);
 }
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::high_resolution_clock Clock;
     {
@@ -126,4 +126,6 @@ int main()
         assert(f.valid());
         assert(t1-t0 < ms(5));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/macro.pass.cpp b/libcxx/test/std/thread/macro.pass.cpp
index bfae0bbee5e5f9aaf9cf7412842bd8b28d516f59..640db4aaa3ef14f2eb815e3a6742333d5b905500 100644
--- a/libcxx/test/std/thread/macro.pass.cpp
+++ b/libcxx/test/std/thread/macro.pass.cpp
@@ -14,9 +14,11 @@
 
 #include <thread>
 
-int main()
+int main(int, char**)
 {
 #ifndef __STDCPP_THREADS__
 #error __STDCPP_THREADS__ is not defined
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.condition/cv_status.pass.cpp b/libcxx/test/std/thread/thread.condition/cv_status.pass.cpp
index af8a10ada41c83c636aef272137783c5d9728191..af980c3eed3655f0ac613f30868746109e55e9b6 100644
--- a/libcxx/test/std/thread/thread.condition/cv_status.pass.cpp
+++ b/libcxx/test/std/thread/thread.condition/cv_status.pass.cpp
@@ -15,8 +15,10 @@
 #include <condition_variable>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert(static_cast<int>(std::cv_status::no_timeout) == 0);
     assert(static_cast<int>(std::cv_status::timeout)    == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.condition/notify_all_at_thread_exit.pass.cpp b/libcxx/test/std/thread/thread.condition/notify_all_at_thread_exit.pass.cpp
index 22fbc98e2a7605e41cedb7411d6d9a120bd7f4d0..9a0e51e3bfcf03b44dafd4f5079768413ca0e5b2 100644
--- a/libcxx/test/std/thread/thread.condition/notify_all_at_thread_exit.pass.cpp
+++ b/libcxx/test/std/thread/thread.condition/notify_all_at_thread_exit.pass.cpp
@@ -36,7 +36,7 @@ void func()
     std::this_thread::sleep_for(ms(300));
 }
 
-int main()
+int main(int, char**)
 {
     std::unique_lock<std::mutex> lk(mut);
     std::thread t(func);
@@ -45,4 +45,6 @@ int main()
     Clock::time_point t1 = Clock::now();
     assert(t1-t0 > ms(250));
     t.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.condition/thread.condition.condvar/assign.fail.cpp b/libcxx/test/std/thread/thread.condition/thread.condition.condvar/assign.fail.cpp
index e308b20e876619030d32adf9caedf6f9bd196e84..a367051fec30af2c0aa08b337681211ae21b64d7 100644
--- a/libcxx/test/std/thread/thread.condition/thread.condition.condvar/assign.fail.cpp
+++ b/libcxx/test/std/thread/thread.condition/thread.condition.condvar/assign.fail.cpp
@@ -15,9 +15,11 @@
 #include <condition_variable>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::condition_variable cv0;
     std::condition_variable cv1;
     cv1 = cv0;
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.condition/thread.condition.condvar/copy.fail.cpp b/libcxx/test/std/thread/thread.condition/thread.condition.condvar/copy.fail.cpp
index d0c4c653dd3ef13857b73a3f657a10d8e01d8bc7..f9d6076579202c8db4464c03918fc8bbe4000db9 100644
--- a/libcxx/test/std/thread/thread.condition/thread.condition.condvar/copy.fail.cpp
+++ b/libcxx/test/std/thread/thread.condition/thread.condition.condvar/copy.fail.cpp
@@ -15,8 +15,10 @@
 #include <condition_variable>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::condition_variable cv0;
     std::condition_variable cv1(cv0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.condition/thread.condition.condvar/default.pass.cpp b/libcxx/test/std/thread/thread.condition/thread.condition.condvar/default.pass.cpp
index 879d3c7dcad0196bd462b34ffeef51c19cdd901b..aab97f9e14a7663f97d0b96b8c33bc41b146d09d 100644
--- a/libcxx/test/std/thread/thread.condition/thread.condition.condvar/default.pass.cpp
+++ b/libcxx/test/std/thread/thread.condition/thread.condition.condvar/default.pass.cpp
@@ -17,7 +17,9 @@
 #include <condition_variable>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::condition_variable cv;
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.condition/thread.condition.condvar/destructor.pass.cpp b/libcxx/test/std/thread/thread.condition/thread.condition.condvar/destructor.pass.cpp
index 85c83f92ac8e9519df78567e2bccdcb3f023d394..6550109fd7954e8868e3b108ec4291f896e94d63 100644
--- a/libcxx/test/std/thread/thread.condition/thread.condition.condvar/destructor.pass.cpp
+++ b/libcxx/test/std/thread/thread.condition/thread.condition.condvar/destructor.pass.cpp
@@ -43,7 +43,7 @@ void g()
         cv->wait(lk);
 }
 
-int main()
+int main(int, char**)
 {
     cv = new std::condition_variable;
     std::thread th2(g);
@@ -54,4 +54,6 @@ int main()
     std::thread th1(f);
     th1.join();
     th2.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.condition/thread.condition.condvar/notify_all.pass.cpp b/libcxx/test/std/thread/thread.condition/thread.condition.condvar/notify_all.pass.cpp
index c281a9d2097c99c20b1ed479b42ec02b1086d6af..46c53a863f5812a21a2858752f637a7811e10f07 100644
--- a/libcxx/test/std/thread/thread.condition/thread.condition.condvar/notify_all.pass.cpp
+++ b/libcxx/test/std/thread/thread.condition/thread.condition.condvar/notify_all.pass.cpp
@@ -46,7 +46,7 @@ void f2()
     test2 = 2;
 }
 
-int main()
+int main(int, char**)
 {
     std::thread t1(f1);
     std::thread t2(f2);
@@ -65,4 +65,6 @@ int main()
     t2.join();
     assert(test1 == 2);
     assert(test2 == 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.condition/thread.condition.condvar/notify_one.pass.cpp b/libcxx/test/std/thread/thread.condition/thread.condition.condvar/notify_one.pass.cpp
index f72d36e8abf6f471cd16665ba93ec3658c339ba8..eb1de67db9fa24504be997146f780dd24f2c58e0 100644
--- a/libcxx/test/std/thread/thread.condition/thread.condition.condvar/notify_one.pass.cpp
+++ b/libcxx/test/std/thread/thread.condition/thread.condition.condvar/notify_one.pass.cpp
@@ -47,7 +47,7 @@ void f2()
     test2 = 2;
 }
 
-int main()
+int main(int, char**)
 {
     std::thread t1(f1);
     std::thread t2(f2);
@@ -95,4 +95,6 @@ int main()
     }
     else
         assert(false);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.condition/thread.condition.condvar/wait.pass.cpp b/libcxx/test/std/thread/thread.condition/thread.condition.condvar/wait.pass.cpp
index a34207406411a714d32d79b54fe2cdf6b080f971..03bcfeea94d76e00e4fd28ef4cd2dd33aa1ce95a 100644
--- a/libcxx/test/std/thread/thread.condition/thread.condition.condvar/wait.pass.cpp
+++ b/libcxx/test/std/thread/thread.condition/thread.condition.condvar/wait.pass.cpp
@@ -36,7 +36,7 @@ void f()
     assert(test2 != 0);
 }
 
-int main()
+int main(int, char**)
 {
     std::unique_lock<std::mutex>lk(mut);
     std::thread t(f);
@@ -48,4 +48,6 @@ int main()
     lk.unlock();
     cv.notify_one();
     t.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.condition/thread.condition.condvar/wait_for.pass.cpp b/libcxx/test/std/thread/thread.condition/thread.condition.condvar/wait_for.pass.cpp
index f34b230c2433caff5ac7bd538592efe603e00f13..505997fff4630d8cf148ddd487436dc54396e6cf 100644
--- a/libcxx/test/std/thread/thread.condition/thread.condition.condvar/wait_for.pass.cpp
+++ b/libcxx/test/std/thread/thread.condition/thread.condition.condvar/wait_for.pass.cpp
@@ -59,7 +59,7 @@ void f()
     ++runs;
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::unique_lock<std::mutex>lk(mut);
@@ -85,4 +85,6 @@ int main()
         lk.unlock();
         t.join();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.condition/thread.condition.condvar/wait_for_pred.pass.cpp b/libcxx/test/std/thread/thread.condition/thread.condition.condvar/wait_for_pred.pass.cpp
index a61b000bdc91dfb3ff33a3df8486e831cc09f3dc..e92ce4583c554ccf9c00b9054c2502a46b906491 100644
--- a/libcxx/test/std/thread/thread.condition/thread.condition.condvar/wait_for_pred.pass.cpp
+++ b/libcxx/test/std/thread/thread.condition/thread.condition.condvar/wait_for_pred.pass.cpp
@@ -66,7 +66,7 @@ void f()
     ++runs;
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::unique_lock<std::mutex>lk(mut);
@@ -92,4 +92,6 @@ int main()
         lk.unlock();
         t.join();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.condition/thread.condition.condvar/wait_pred.pass.cpp b/libcxx/test/std/thread/thread.condition/thread.condition.condvar/wait_pred.pass.cpp
index f99436a5e29b122bdf24fe765fc1289b8f34ccd0..0de8524ed1ed80769a13efb737467dfef3ac2ad3 100644
--- a/libcxx/test/std/thread/thread.condition/thread.condition.condvar/wait_pred.pass.cpp
+++ b/libcxx/test/std/thread/thread.condition/thread.condition.condvar/wait_pred.pass.cpp
@@ -46,7 +46,7 @@ void f()
     assert(test2 != 0);
 }
 
-int main()
+int main(int, char**)
 {
     std::unique_lock<std::mutex>lk(mut);
     std::thread t(f);
@@ -58,4 +58,6 @@ int main()
     lk.unlock();
     cv.notify_one();
     t.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.condition/thread.condition.condvar/wait_until.pass.cpp b/libcxx/test/std/thread/thread.condition/thread.condition.condvar/wait_until.pass.cpp
index f954ae25ee246ce974da28778472459e27c20a34..7f1bdf827cbff2906e320e8131fcda5d017a62c5 100644
--- a/libcxx/test/std/thread/thread.condition/thread.condition.condvar/wait_until.pass.cpp
+++ b/libcxx/test/std/thread/thread.condition/thread.condition.condvar/wait_until.pass.cpp
@@ -72,7 +72,7 @@ void f()
     ++runs;
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::unique_lock<std::mutex>lk(mut);
@@ -98,4 +98,6 @@ int main()
         lk.unlock();
         t.join();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.condition/thread.condition.condvar/wait_until_pred.pass.cpp b/libcxx/test/std/thread/thread.condition/thread.condition.condvar/wait_until_pred.pass.cpp
index 8307a52c0e39d09aeb709c90e3e994ab383145e1..f21b1b54bc66adc27a68953606cf581ff839ad59 100644
--- a/libcxx/test/std/thread/thread.condition/thread.condition.condvar/wait_until_pred.pass.cpp
+++ b/libcxx/test/std/thread/thread.condition/thread.condition.condvar/wait_until_pred.pass.cpp
@@ -85,7 +85,7 @@ void f()
     ++runs;
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::unique_lock<std::mutex>lk(mut);
@@ -111,4 +111,6 @@ int main()
         lk.unlock();
         t.join();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/assign.fail.cpp b/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/assign.fail.cpp
index 214164ea72ac68a1a55adfea2dd9d99888ed58aa..0c2adc9a5381c7a7625c28cc39ea816eefac5f04 100644
--- a/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/assign.fail.cpp
+++ b/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/assign.fail.cpp
@@ -15,9 +15,11 @@
 #include <condition_variable>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::condition_variable_any cv0;
     std::condition_variable_any cv1;
     cv1 = cv0;
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/copy.fail.cpp b/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/copy.fail.cpp
index 6eafc62024f355d99d45cafed5c69f255f31aab2..5aff93ba0fac91652f5748731c0a787f32aabcf4 100644
--- a/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/copy.fail.cpp
+++ b/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/copy.fail.cpp
@@ -15,8 +15,10 @@
 #include <condition_variable>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::condition_variable_any cv0;
     std::condition_variable_any cv1(cv0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/default.pass.cpp b/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/default.pass.cpp
index 05ebff0680743f157b729fe39c2aeb82b3878868..0c35da0321b2f2e21ad9e1be0e7ac7477cde3cac 100644
--- a/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/default.pass.cpp
+++ b/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/default.pass.cpp
@@ -17,7 +17,9 @@
 #include <condition_variable>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::condition_variable_any cv;
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/destructor.pass.cpp b/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/destructor.pass.cpp
index 57b3024fe0a3056671840824b9c9c8e64d853356..35580d4293b400c65933a97c70fd9a0828b5ecf9 100644
--- a/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/destructor.pass.cpp
+++ b/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/destructor.pass.cpp
@@ -44,7 +44,7 @@ void g()
     m.unlock();
 }
 
-int main()
+int main(int, char**)
 {
     cv = new std::condition_variable_any;
     std::thread th2(g);
@@ -55,4 +55,6 @@ int main()
     std::thread th1(f);
     th1.join();
     th2.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/notify_all.pass.cpp b/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/notify_all.pass.cpp
index cb79d8a6b6c6db5d9620a511f0a8ee2bff337d67..d12c9360288594b56c5f48019d6d7e45e1f1abc3 100644
--- a/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/notify_all.pass.cpp
+++ b/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/notify_all.pass.cpp
@@ -50,7 +50,7 @@ void f2()
     test2 = 2;
 }
 
-int main()
+int main(int, char**)
 {
     std::thread t1(f1);
     std::thread t2(f2);
@@ -69,4 +69,6 @@ int main()
     t2.join();
     assert(test1 == 2);
     assert(test2 == 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/notify_one.pass.cpp b/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/notify_one.pass.cpp
index e5c0a0943c9ed6e750eeb76f80735edcbfde154a..27a0f87e59fe7b6bc826fc934e188d51d9a6d660 100644
--- a/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/notify_one.pass.cpp
+++ b/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/notify_one.pass.cpp
@@ -52,7 +52,7 @@ void f2()
     test2 = 2;
 }
 
-int main()
+int main(int, char**)
 {
     std::thread t1(f1);
     std::thread t2(f2);
@@ -96,4 +96,6 @@ int main()
     }
     else
         assert(false);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait.pass.cpp b/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait.pass.cpp
index 741094bddfaa88a42370048de2b384bdefe3b8b9..a3b2e87c9e9eb6be7a8b5a571edb9b7f69418763 100644
--- a/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait.pass.cpp
+++ b/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait.pass.cpp
@@ -41,7 +41,7 @@ void f()
     assert(test2 != 0);
 }
 
-int main()
+int main(int, char**)
 {
     L1 lk(m0);
     std::thread t(f);
@@ -53,4 +53,6 @@ int main()
     lk.unlock();
     cv.notify_one();
     t.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait_for.pass.cpp b/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait_for.pass.cpp
index ec4eb3398960d5c97c7db7b589da2d98ac35bb3c..d472a698feca69026625a94067c4bf6458bf2374 100644
--- a/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait_for.pass.cpp
+++ b/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait_for.pass.cpp
@@ -62,7 +62,7 @@ void f()
     ++runs;
 }
 
-int main()
+int main(int, char**)
 {
     {
         L1 lk(m0);
@@ -88,4 +88,6 @@ int main()
         lk.unlock();
         t.join();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait_for_pred.pass.cpp b/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait_for_pred.pass.cpp
index 81d69861fe9906504582bd172e559e2e6123421f..cbf0193ade392bf086916b5c3f29fb95b9138ca4 100644
--- a/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait_for_pred.pass.cpp
+++ b/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait_for_pred.pass.cpp
@@ -70,7 +70,7 @@ void f()
     ++runs;
 }
 
-int main()
+int main(int, char**)
 {
     {
         expect_result = true;
@@ -98,4 +98,6 @@ int main()
         lk.unlock();
         t.join();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait_pred.pass.cpp b/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait_pred.pass.cpp
index d76cbd443a9030baea98aec9834ba1de058d40cd..eafc434d0c283a40b3b72babbfb0f3cb5e6f697f 100644
--- a/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait_pred.pass.cpp
+++ b/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait_pred.pass.cpp
@@ -50,7 +50,7 @@ void f()
     assert(test2 != 0);
 }
 
-int main()
+int main(int, char**)
 {
     L1 lk(m0);
     std::thread t(f);
@@ -62,4 +62,6 @@ int main()
     lk.unlock();
     cv.notify_one();
     t.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait_terminates.sh.cpp b/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait_terminates.sh.cpp
index 796b66e99b6abc16983031f5279a7a2fddb1c016..8afa0515920c7d41053c5fd7ab265248007b9c39 100644
--- a/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait_terminates.sh.cpp
+++ b/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait_terminates.sh.cpp
@@ -109,7 +109,7 @@ void signal_me() {
 typedef std::chrono::system_clock Clock;
 typedef std::chrono::milliseconds MS;
 
-int main(int argc, char** argv) {
+int main(int argc, char **argv) {
   assert(argc == 2);
   int id = std::stoi(argv[1]);
   assert(id >= 1 && id <= 6);
@@ -130,4 +130,6 @@ int main(int argc, char** argv) {
     }
   } catch (...) {}
   assert(false);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait_until.pass.cpp b/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait_until.pass.cpp
index 276597350f6df9fcd831f212bc61e5007b4cfb23..e14944906b710f244a2fe57171d522dcba8e9093 100644
--- a/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait_until.pass.cpp
+++ b/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait_until.pass.cpp
@@ -75,7 +75,7 @@ void f()
     ++runs;
 }
 
-int main()
+int main(int, char**)
 {
     {
         L1 lk(m0);
@@ -101,4 +101,6 @@ int main()
         lk.unlock();
         t.join();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait_until_pred.pass.cpp b/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait_until_pred.pass.cpp
index 0216688d7e2add40f6ab0f9eb3fd0fda2e1b3211..5eb253a75fc5634328a8a0e81b2ea7e9960418b6 100644
--- a/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait_until_pred.pass.cpp
+++ b/libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait_until_pred.pass.cpp
@@ -89,7 +89,7 @@ void f()
     ++runs;
 }
 
-int main()
+int main(int, char**)
 {
     {
         L1 lk(m0);
@@ -115,4 +115,6 @@ int main()
         lk.unlock();
         t.join();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.general/nothing_to_do.pass.cpp b/libcxx/test/std/thread/thread.general/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/thread/thread.general/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/thread/thread.general/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock.algorithm/lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock.algorithm/lock.pass.cpp
index 1c7de834940000e8650cc0b158a711c3cf12be62..207b0753e7262933d60fa863acb7dcd96b021ae5 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock.algorithm/lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock.algorithm/lock.pass.cpp
@@ -92,7 +92,7 @@ public:
     bool locked() const {return locked_;}
 };
 
-int main()
+int main(int, char**)
 {
     {
         L0 l0;
@@ -518,4 +518,6 @@ int main()
     }
 #endif  // TEST_HAS_NO_EXCEPTIONS
 #endif // TEST_STD_VER >= 11
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock.algorithm/try_lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock.algorithm/try_lock.pass.cpp
index 7856ab96f8b7b0da58c49e3e32994639abd7712a..50ff29ce95978c481814051a6d22e4abda7a2185 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock.algorithm/try_lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock.algorithm/try_lock.pass.cpp
@@ -72,7 +72,7 @@ public:
     bool locked() const {return locked_;}
 };
 
-int main()
+int main(int, char**)
 {
     {
         L0 l0;
@@ -522,4 +522,6 @@ int main()
         assert(!l3.locked());
     }
 #endif  // TEST_STD_VER >= 11
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/adopt_lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/adopt_lock.pass.cpp
index 273a4881355d3ca742dee0421ecd43ba8dccb8bd..fc76eb34eb4ae497478a640a2a039feccbf40794 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/adopt_lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/adopt_lock.pass.cpp
@@ -42,11 +42,13 @@ void f()
     assert(d < ms(50));  // within 50ms
 }
 
-int main()
+int main(int, char**)
 {
     m.lock();
     std::thread t(f);
     std::this_thread::sleep_for(ms(250));
     m.unlock();
     t.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/assign.fail.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/assign.fail.cpp
index b22e0db9efdb509bea4a74f766f9b02fb8bb5e25..2d0f438ed03918d714dfe66d78ab7500d7b24dfe 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/assign.fail.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/assign.fail.cpp
@@ -14,11 +14,13 @@
 
 #include <mutex>
 
-int main()
+int main(int, char**)
 {
     std::mutex m0;
     std::mutex m1;
     std::lock_guard<std::mutex> lg0(m0);
     std::lock_guard<std::mutex> lg(m1);
     lg = lg0;
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/copy.fail.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/copy.fail.cpp
index 1852db1e5a09b7d3ccc19ff60cde0995f3b24aec..e99517e47e8c63c1ee2d650bc5ed13ec83dfc2e0 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/copy.fail.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/copy.fail.cpp
@@ -14,9 +14,11 @@
 
 #include <mutex>
 
-int main()
+int main(int, char**)
 {
     std::mutex m;
     std::lock_guard<std::mutex> lg0(m);
     std::lock_guard<std::mutex> lg(lg0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/mutex.fail.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/mutex.fail.cpp
index 52a0397de55b86b8197265e3c8c650c662c83500..383c1539a60bc7d6eacffd1fadc2d38b97e05df9 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/mutex.fail.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/mutex.fail.cpp
@@ -16,8 +16,10 @@
 
 #include <mutex>
 
-int main()
+int main(int, char**)
 {
     std::mutex m;
     std::lock_guard<std::mutex> lg = m; // expected-error{{no viable conversion}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/mutex.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/mutex.pass.cpp
index 84353486bac5d8eaf81bd95c15a2ca95f8920783..fa6aa4615aa832017d0078612eece8a08a346655 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/mutex.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/mutex.pass.cpp
@@ -46,7 +46,7 @@ void f()
     assert(d < ms(200));  // within 200ms
 }
 
-int main()
+int main(int, char**)
 {
     m.lock();
     std::thread t(f);
@@ -58,4 +58,6 @@ int main()
     std::lock_guard lg(m);
     static_assert((std::is_same<decltype(lg), std::lock_guard<decltype(m)>>::value), "" );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/types.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/types.pass.cpp
index 745633b55c7504cf5517ab3c5be207c3c7286b7d..b9cdb4dec5df2e089cefe9a4342b3b4f8034b001 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/types.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.guard/types.pass.cpp
@@ -21,8 +21,10 @@
 #include <mutex>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::lock_guard<std::mutex>::mutex_type,
                    std::mutex>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.scoped/adopt_lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.scoped/adopt_lock.pass.cpp
index edaf09c5a1dbca1783104c3cbd1e60e480d0ae5d..63e0626d532d51bf5799e2b94cc9d734252ac246 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.scoped/adopt_lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.scoped/adopt_lock.pass.cpp
@@ -31,7 +31,7 @@ struct TestMutex {
     TestMutex& operator=(TestMutex const&) = delete;
 };
 
-int main()
+int main(int, char**)
 {
     {
         using LG = std::scoped_lock<>;
@@ -68,4 +68,6 @@ int main()
         assert(!m1.locked && !m2.locked && !m3.locked);
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.scoped/assign.fail.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.scoped/assign.fail.cpp
index d88b4dedc933a7ed7f32047e0a83698e1e07f0dd..66a68bb276557e835c5a36746c95d2fc1655f57e 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.scoped/assign.fail.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.scoped/assign.fail.cpp
@@ -18,7 +18,7 @@
 #include <mutex>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using M = std::mutex;
     M m0, m1, m2;
@@ -46,4 +46,6 @@ int main()
         LG lg2(om0, om1, om2);
         lg1 = lg2; // expected-error{{overload resolution selected deleted operator '='}}
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.scoped/copy.fail.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.scoped/copy.fail.cpp
index 16938731b7b8125d3a4aa497f03d222f32e48bc3..3829d15a6254ecbb2417ec104f0c8d34ef76ebb3 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.scoped/copy.fail.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.scoped/copy.fail.cpp
@@ -18,7 +18,7 @@
 #include <mutex>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using M = std::mutex;
     M m0, m1, m2;
@@ -42,4 +42,6 @@ int main()
         const LG Orig(m0, m1, m2);
         LG Copy(Orig); // expected-error{{call to deleted constructor of 'LG'}}
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.scoped/mutex.fail.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.scoped/mutex.fail.cpp
index 4f25ec237aa2456cbad08cd3373811d85cf35d50..0c9258887d3d61d26d7de52d8f6ad81d3dbebc45 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.scoped/mutex.fail.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.scoped/mutex.fail.cpp
@@ -21,7 +21,7 @@
 template <class LG>
 void test_conversion(LG) {}
 
-int main()
+int main(int, char**)
 {
     using M = std::mutex;
     M m0, m1, m2;
@@ -49,4 +49,6 @@ int main()
         LG lg = {m0, m1, m2}; // expected-error{{chosen constructor is explicit in copy-initialization}}
         test_conversion<LG>({n0, n1, n2}); // expected-error{{no matching function for call}}
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.scoped/mutex.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.scoped/mutex.pass.cpp
index 219c389aa02701a38501d8f11a10412787548326..3a633c39b0385d2bf9c5c430ca261b286153abe4 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.scoped/mutex.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.scoped/mutex.pass.cpp
@@ -61,7 +61,7 @@ struct TestMutexThrows {
 };
 #endif // !defined(TEST_HAS_NO_EXCEPTIONS)
 
-int main()
+int main(int, char**)
 {
     {
         using LG = std::scoped_lock<>;
@@ -151,4 +151,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.scoped/types.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.scoped/types.pass.cpp
index 5228ccead8769ce375f698a40fef427a708e9f75..62621fccad71067d856acfa9ed1787afdd3d03f9 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.scoped/types.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.scoped/types.pass.cpp
@@ -36,7 +36,7 @@ constexpr bool has_mutex_type() {
     return !std::is_same<decltype(test_typedef<LG>(0)), NAT>::value;
 }
 
-int main()
+int main(int, char**)
 {
     {
         using T = std::scoped_lock<>;
@@ -74,4 +74,6 @@ int main()
         using T = std::scoped_lock<M1, M1, M1>;
         static_assert(!has_mutex_type<T>(), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/copy_assign.fail.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/copy_assign.fail.cpp
index ff6c376da2c7c96b5ea49aa380b758f64f03ce89..1b31fbc50d244a55bff67dfd8719413b6335dc11 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/copy_assign.fail.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/copy_assign.fail.cpp
@@ -18,9 +18,11 @@
 std::shared_timed_mutex m0;
 std::shared_timed_mutex m1;
 
-int main()
+int main(int, char**)
 {
     std::shared_lock<std::shared_timed_mutex> lk0(m0);
     std::shared_lock<std::shared_timed_mutex> lk1(m1);
     lk1 = lk0;
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/copy_ctor.fail.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/copy_ctor.fail.cpp
index 6f1f2e9ab0488fd0f21232d14cf1259f859e8457..48da3c715fa39973294f3628a1c781febb58c954 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/copy_ctor.fail.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/copy_ctor.fail.cpp
@@ -17,8 +17,10 @@
 
 std::shared_timed_mutex m;
 
-int main()
+int main(int, char**)
 {
     std::shared_lock<std::shared_timed_mutex> lk0(m);
     std::shared_lock<std::shared_timed_mutex> lk = lk0;
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/default.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/default.pass.cpp
index 2d571cb51db258d0c2c79dcbe8f949a6fb1a1f75..0543ae72e82f7796ca9e6e4dc76340315d72feac 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/default.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/default.pass.cpp
@@ -18,9 +18,11 @@
 #include <shared_mutex>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::shared_lock<std::shared_timed_mutex> ul;
     assert(!ul.owns_lock());
     assert(ul.mutex() == nullptr);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/move_assign.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/move_assign.pass.cpp
index 960948421d28caf411f066eea35748db42c32d20..999d65f028b31cfd9f1e6ff6757c33ec5d1dc4e5 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/move_assign.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/move_assign.pass.cpp
@@ -20,7 +20,7 @@
 #include "nasty_containers.hpp"
 
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::shared_timed_mutex M;
@@ -46,4 +46,6 @@ int main()
     assert(lk0.mutex() == nullptr);
     assert(lk0.owns_lock() == false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/move_ctor.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/move_ctor.pass.cpp
index 6be2e774b006938061b113560a9f32f971abea1b..1f61e21fbcf0ab12ffd1d56e91c1dbd68375f326 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/move_ctor.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/move_ctor.pass.cpp
@@ -19,7 +19,7 @@
 #include <cassert>
 #include "nasty_containers.hpp"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::shared_timed_mutex M;
@@ -41,4 +41,6 @@ int main()
     assert(lk0.mutex() == nullptr);
     assert(lk0.owns_lock() == false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex.pass.cpp
index 1204eb1f01802cc4d36a38f2ece45563ed73ef3b..14c084f008dd0be4c3623e2b85280617edfcc1e2 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex.pass.cpp
@@ -71,7 +71,7 @@ void g()
     assert(d < Tolerance);  // within tolerance
 }
 
-int main()
+int main(int, char**)
 {
     std::vector<std::thread> v;
     {
@@ -99,4 +99,6 @@ int main()
     std::shared_lock sl(m);
     static_assert((std::is_same<decltype(sl), std::shared_lock<decltype(m)>>::value), "" );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex_adopt_lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex_adopt_lock.pass.cpp
index 2b5fae21bdc22fa952a10e0c521857e4b9ea6003..86d54b5083bf59252a12a50fcab40c4da6b5c149 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex_adopt_lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex_adopt_lock.pass.cpp
@@ -19,7 +19,7 @@
 #include <cassert>
 #include "nasty_containers.hpp"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::shared_timed_mutex M;
@@ -37,4 +37,6 @@ int main()
     assert(lk.mutex() == std::addressof(m));
     assert(lk.owns_lock() == true);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex_defer_lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex_defer_lock.pass.cpp
index c7d0a192b7915edca458029aa7500a164e1ad474..5a085d2e6ae15f874e1d07df9cc84b4217a210c7 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex_defer_lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex_defer_lock.pass.cpp
@@ -19,7 +19,7 @@
 #include <cassert>
 #include "nasty_containers.hpp"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::shared_timed_mutex M;
@@ -35,4 +35,6 @@ int main()
     assert(lk.mutex() == std::addressof(m));
     assert(lk.owns_lock() == false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex_duration.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex_duration.pass.cpp
index f633c2e8c65aad1f7c4082a961cd91c6e2e9351f..3228f938f90366fa207575b359536485976177ef 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex_duration.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex_duration.pass.cpp
@@ -66,7 +66,7 @@ void f2()
     assert(d < Tolerance);  // within 50ms
 }
 
-int main()
+int main(int, char**)
 {
     {
         m.lock();
@@ -88,4 +88,6 @@ int main()
         for (auto& t : v)
             t.join();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex_time_point.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex_time_point.pass.cpp
index c899cea3e047673431264579155e86b67ab4d562..f62e739443a551297b0f1873209f9dd17f43d48a 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex_time_point.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex_time_point.pass.cpp
@@ -65,7 +65,7 @@ void f2()
     assert(d < Tolerance);  // within 50ms
 }
 
-int main()
+int main(int, char**)
 {
     {
         m.lock();
@@ -87,4 +87,6 @@ int main()
         for (auto& t : v)
             t.join();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex_try_to_lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex_try_to_lock.pass.cpp
index 4375a2b9978f4a44ab6c06bebf6de594132b315a..7dd7c16fe5bca696c612d79cfff65d7c17d462f4 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex_try_to_lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex_try_to_lock.pass.cpp
@@ -57,7 +57,7 @@ void f()
     assert(d < ms(200));  // within 200ms
 }
 
-int main()
+int main(int, char**)
 {
     m.lock();
     std::vector<std::thread> v;
@@ -67,4 +67,6 @@ int main()
     m.unlock();
     for (auto& t : v)
         t.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.locking/lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.locking/lock.pass.cpp
index 7726337c8c788433156e240b1017718e7a26e7bc..5f084b21259f068f7d0918fc7c8e28b4b6b441f2 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.locking/lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.locking/lock.pass.cpp
@@ -80,7 +80,7 @@ void f()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     m.lock();
     std::vector<std::thread> v;
@@ -90,4 +90,6 @@ int main()
     m.unlock();
     for (auto& t : v)
         t.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.locking/try_lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.locking/try_lock.pass.cpp
index 884dd47b092365ddf1eb34ed99b18f85aac75473..488260618bc84218be5c05f852e72b8449fdd08a 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.locking/try_lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.locking/try_lock.pass.cpp
@@ -34,7 +34,7 @@ struct mutex
 
 mutex m;
 
-int main()
+int main(int, char**)
 {
     std::shared_lock<mutex> lk(m, std::defer_lock);
     assert(lk.try_lock() == true);
@@ -67,4 +67,6 @@ int main()
         assert(e.code().value() == EPERM);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.locking/try_lock_for.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.locking/try_lock_for.pass.cpp
index e6df4f121f3797ba3200880c39fbb194476ea848..b2c1776839b9335eff1e2127603fce1e61bd9316 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.locking/try_lock_for.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.locking/try_lock_for.pass.cpp
@@ -39,7 +39,7 @@ struct mutex
 
 mutex m;
 
-int main()
+int main(int, char**)
 {
     std::shared_lock<mutex> lk(m, std::defer_lock);
     assert(lk.try_lock_for(ms(5)) == true);
@@ -72,4 +72,6 @@ int main()
         assert(e.code().value() == EPERM);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.locking/try_lock_until.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.locking/try_lock_until.pass.cpp
index 74e0ecc23e7448267e77ebe23e2fb0861d0b5729..59bcd4a0bd82c9bc73367170a7ed5e67e760da02 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.locking/try_lock_until.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.locking/try_lock_until.pass.cpp
@@ -38,7 +38,7 @@ struct mutex
 
 mutex m;
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::steady_clock Clock;
     std::shared_lock<mutex> lk(m, std::defer_lock);
@@ -72,4 +72,6 @@ int main()
         assert(e.code().value() == EPERM);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.locking/unlock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.locking/unlock.pass.cpp
index 6c100470e34f944d73d78982103acf48653812a2..b0e337bda5fb2637e3afea3a33637ebf81bd51d6 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.locking/unlock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.locking/unlock.pass.cpp
@@ -30,7 +30,7 @@ struct mutex
 
 mutex m;
 
-int main()
+int main(int, char**)
 {
     std::shared_lock<mutex> lk(m);
     lk.unlock();
@@ -59,4 +59,6 @@ int main()
         assert(e.code().value() == EPERM);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.mod/member_swap.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.mod/member_swap.pass.cpp
index 22eb3ee48e66158af58eb632288c0feb7cdfd313..ce385ddbd66153f1358f83db7a14922b03d8e9cd 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.mod/member_swap.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.mod/member_swap.pass.cpp
@@ -26,7 +26,7 @@ struct mutex
 
 mutex m;
 
-int main()
+int main(int, char**)
 {
     std::shared_lock<mutex> lk1(m);
     std::shared_lock<mutex> lk2;
@@ -36,4 +36,6 @@ int main()
     assert(lk2.mutex() == &m);
     assert(lk2.owns_lock() == true);
     static_assert(noexcept(lk1.swap(lk2)), "member swap must be noexcept");
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.mod/nonmember_swap.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.mod/nonmember_swap.pass.cpp
index 65e05d39f5c5bd09bda9ff4a53d3ebac6119e6df..cec13f0f2f7e16e1e68a102312556ac35fcee578 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.mod/nonmember_swap.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.mod/nonmember_swap.pass.cpp
@@ -27,7 +27,7 @@ struct mutex
 
 mutex m;
 
-int main()
+int main(int, char**)
 {
     std::shared_lock<mutex> lk1(m);
     std::shared_lock<mutex> lk2;
@@ -37,4 +37,6 @@ int main()
     assert(lk2.mutex() == &m);
     assert(lk2.owns_lock() == true);
     static_assert(noexcept(swap(lk1, lk2)), "non-member swap must be noexcept");
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.mod/release.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.mod/release.pass.cpp
index d387a83518052df9989408786235f129b9d631fb..f2e5820cf0c7059f7aa0c469730a93db1a24e375 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.mod/release.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.mod/release.pass.cpp
@@ -31,7 +31,7 @@ int mutex::unlock_count = 0;
 
 mutex m;
 
-int main()
+int main(int, char**)
 {
     std::shared_lock<mutex> lk(m);
     assert(lk.mutex() == &m);
@@ -44,4 +44,6 @@ int main()
     assert(mutex::lock_count == 1);
     assert(mutex::unlock_count == 0);
     static_assert(noexcept(lk.release()), "release must be noexcept");
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.obs/mutex.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.obs/mutex.pass.cpp
index 28685954ba7708451c7879d66b41836aba725138..867bae0e37150cd82dc4168afffb135e6e58ac46 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.obs/mutex.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.obs/mutex.pass.cpp
@@ -20,7 +20,7 @@
 
 std::shared_timed_mutex m;
 
-int main()
+int main(int, char**)
 {
     std::shared_lock<std::shared_timed_mutex> lk0;
     assert(lk0.mutex() == nullptr);
@@ -29,4 +29,6 @@ int main()
     lk1.unlock();
     assert(lk1.mutex() == &m);
     static_assert(noexcept(lk0.mutex()), "mutex() must be noexcept");
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.obs/op_bool.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.obs/op_bool.pass.cpp
index 1064d727c69fb73dc4c2a08594312283f4783e9a..82d737ee5e599822015da2c3f2e742c5ffc29a71 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.obs/op_bool.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.obs/op_bool.pass.cpp
@@ -20,7 +20,7 @@
 
 std::shared_timed_mutex m;
 
-int main()
+int main(int, char**)
 {
     std::shared_lock<std::shared_timed_mutex> lk0;
     assert(static_cast<bool>(lk0) == false);
@@ -29,4 +29,6 @@ int main()
     lk1.unlock();
     assert(static_cast<bool>(lk1) == false);
     static_assert(noexcept(static_cast<bool>(lk0)), "explicit operator bool() must be noexcept");
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.obs/owns_lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.obs/owns_lock.pass.cpp
index 36a2c0f835dc228e33675779e15eda70dd40c4b8..f949684e834df33fe7faee5bbd92f2ea12b80a42 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.obs/owns_lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.obs/owns_lock.pass.cpp
@@ -20,7 +20,7 @@
 
 std::shared_timed_mutex m;
 
-int main()
+int main(int, char**)
 {
     std::shared_lock<std::shared_timed_mutex> lk0;
     assert(lk0.owns_lock() == false);
@@ -29,4 +29,6 @@ int main()
     lk1.unlock();
     assert(lk1.owns_lock() == false);
     static_assert(noexcept(lk0.owns_lock()), "owns_lock must be noexcept");
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/types.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/types.pass.cpp
index c5be52afea2ae048ddf2c942d36d8bd8d27ac6bd..44d19e8dbb4dca94db65fa6dea1f348d76204407 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/types.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/types.pass.cpp
@@ -23,8 +23,10 @@
 #include <shared_mutex>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::shared_lock<std::mutex>::mutex_type,
                    std::mutex>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/copy_assign.fail.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/copy_assign.fail.cpp
index 0579910465736c4c07048d23d0df26ca96ee6412..799cb61f9b21e0a09f945f2edd5eae025ef30080 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/copy_assign.fail.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/copy_assign.fail.cpp
@@ -15,7 +15,7 @@
 #include <mutex>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::mutex M;
@@ -29,4 +29,6 @@ int main()
     assert(lk0.mutex() == nullptr);
     assert(lk0.owns_lock() == false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/copy_ctor.fail.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/copy_ctor.fail.cpp
index 12045f9989d58bbe90eacb3cb8c282a6e7862448..e258198e60bbf772674cb4c1f1bbe686ab8fa9b6 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/copy_ctor.fail.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/copy_ctor.fail.cpp
@@ -15,7 +15,7 @@
 #include <mutex>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::mutex M;
@@ -27,4 +27,6 @@ int main()
     assert(lk0.mutex() == nullptr);
     assert(lk0.owns_lock() == false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/default.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/default.pass.cpp
index 46f4f1e801334ab90d0d4b47a862e437a9546d14..74b265141023302530f5362cfb86e68abdb09a1b 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/default.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/default.pass.cpp
@@ -17,9 +17,11 @@
 #include <mutex>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::unique_lock<std::mutex> ul;
     assert(!ul.owns_lock());
     assert(ul.mutex() == nullptr);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/move_assign.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/move_assign.pass.cpp
index 16b1bd8c554b58fbcd9065dc9b63c12b4355f9ce..1e663766b10baa4dbafdc92402e1ad8e3dd6ac3e 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/move_assign.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/move_assign.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include "nasty_containers.hpp"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::mutex M;
@@ -44,4 +44,6 @@ int main()
     assert(lk0.mutex() == nullptr);
     assert(lk0.owns_lock() == false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/move_ctor.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/move_ctor.pass.cpp
index 2c4993702b10a8c8c5d90143606394e0c60843c8..8ea0a1f2d461cf740393a57351b5abf2a269b9cb 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/move_ctor.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/move_ctor.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include "nasty_containers.hpp"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::mutex M;
@@ -40,4 +40,6 @@ int main()
     assert(lk0.mutex() == nullptr);
     assert(lk0.owns_lock() == false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/mutex.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/mutex.pass.cpp
index 30897b3d8621321d800c1b205be9436f6273e802..61c0dacf17a47f2a6e38141094a16e8f82c77521 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/mutex.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/mutex.pass.cpp
@@ -46,7 +46,7 @@ void f()
     assert(d < ms(50));  // within 50ms
 }
 
-int main()
+int main(int, char**)
 {
     m.lock();
     std::thread t(f);
@@ -58,4 +58,6 @@ int main()
     std::unique_lock ul(m);
     static_assert((std::is_same<decltype(ul), std::unique_lock<decltype(m)>>::value), "" );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/mutex_adopt_lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/mutex_adopt_lock.pass.cpp
index 1c258d6a64a31dc0a22aff17a0ef8b01e9ef39f9..d957c6d24b026c429c2aa3d0c913d735d6626f0b 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/mutex_adopt_lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/mutex_adopt_lock.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include "nasty_containers.hpp"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::mutex M;
@@ -36,4 +36,6 @@ int main()
     assert(lk.mutex() == std::addressof(m));
     assert(lk.owns_lock() == true);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/mutex_defer_lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/mutex_defer_lock.pass.cpp
index 5f4ab4e7413c6eb29f6d768f47be2193ae55e587..af6853160f6203d2a9a3ded7b77164c98201059c 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/mutex_defer_lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/mutex_defer_lock.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include "nasty_containers.hpp"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::mutex M;
@@ -34,4 +34,6 @@ int main()
     assert(lk.mutex() == std::addressof(m));
     assert(lk.owns_lock() == false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/mutex_duration.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/mutex_duration.pass.cpp
index 8fee76b8fe71aece8f17a8d5490e22d1cc874023..8699dd554affbc2d2868a5b500755e1cc533b2e4 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/mutex_duration.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/mutex_duration.pass.cpp
@@ -50,7 +50,7 @@ void f2()
     assert(d < ms(50));  // within 50ms
 }
 
-int main()
+int main(int, char**)
 {
     {
         m.lock();
@@ -66,4 +66,6 @@ int main()
         m.unlock();
         t.join();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/mutex_time_point.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/mutex_time_point.pass.cpp
index 4cd2efeba2b3abc6f80763d4b807bd4fc506d528..ab46dacad3c765f18c3350235d46bb14d8f2478a 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/mutex_time_point.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/mutex_time_point.pass.cpp
@@ -50,7 +50,7 @@ void f2()
     assert(d < ms(50));  // within 50ms
 }
 
-int main()
+int main(int, char**)
 {
     {
         m.lock();
@@ -66,4 +66,6 @@ int main()
         m.unlock();
         t.join();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/mutex_try_to_lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/mutex_try_to_lock.pass.cpp
index 3c385808bf3d85806bfaf04a5986da7e9646efbd..448be8e7e142b3c779c3b2d9627dac0258e92dce 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/mutex_try_to_lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.cons/mutex_try_to_lock.pass.cpp
@@ -53,11 +53,13 @@ void f()
     assert(d < ms(200));  // within 200ms
 }
 
-int main()
+int main(int, char**)
 {
     m.lock();
     std::thread t(f);
     std::this_thread::sleep_for(ms(250));
     m.unlock();
     t.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.locking/lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.locking/lock.pass.cpp
index 536a0d7d22c0138a271cd1d18cfad048c52ad29f..b8a0c2d343e55703961e489597766c3ea1c74d0b 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.locking/lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.locking/lock.pass.cpp
@@ -66,11 +66,13 @@ void f()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     m.lock();
     std::thread t(f);
     std::this_thread::sleep_for(ms(250));
     m.unlock();
     t.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.locking/try_lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.locking/try_lock.pass.cpp
index cfc0befcab1da71041fe3f857ba58a8806b5dbca..a6247df7ede89bd077e81bb078c391c7d4722aa4 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.locking/try_lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.locking/try_lock.pass.cpp
@@ -33,7 +33,7 @@ struct mutex
 
 mutex m;
 
-int main()
+int main(int, char**)
 {
     std::unique_lock<mutex> lk(m, std::defer_lock);
     assert(lk.try_lock() == true);
@@ -66,4 +66,6 @@ int main()
         assert(e.code().value() == EPERM);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.locking/try_lock_for.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.locking/try_lock_for.pass.cpp
index f1a2ef6c414187242b206be0c262ef7b1df8c302..a6166ceda869c14fd2c0331e66ba16a04da1531b 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.locking/try_lock_for.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.locking/try_lock_for.pass.cpp
@@ -38,7 +38,7 @@ struct mutex
 
 mutex m;
 
-int main()
+int main(int, char**)
 {
     std::unique_lock<mutex> lk(m, std::defer_lock);
     assert(lk.try_lock_for(ms(5)) == true);
@@ -71,4 +71,6 @@ int main()
         assert(e.code().value() == EPERM);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.locking/try_lock_until.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.locking/try_lock_until.pass.cpp
index 60616da935f51af3c1c91be38de404420f9833b6..6c7da1c0cdff2b52a49a79690f98501372dad87a 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.locking/try_lock_until.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.locking/try_lock_until.pass.cpp
@@ -37,7 +37,7 @@ struct mutex
 
 mutex m;
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::steady_clock Clock;
     std::unique_lock<mutex> lk(m, std::defer_lock);
@@ -71,4 +71,6 @@ int main()
         assert(e.code().value() == EPERM);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.locking/unlock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.locking/unlock.pass.cpp
index bb0c00ded28b8299f83cf3d4c51f075c2332e80f..1f0a0e529dc49e1151ec92db8c0c4b563410df5a 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.locking/unlock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.locking/unlock.pass.cpp
@@ -29,7 +29,7 @@ struct mutex
 
 mutex m;
 
-int main()
+int main(int, char**)
 {
     std::unique_lock<mutex> lk(m);
     lk.unlock();
@@ -58,4 +58,6 @@ int main()
         assert(e.code().value() == EPERM);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.mod/member_swap.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.mod/member_swap.pass.cpp
index 3c89d6cf8e02d85b169272a6a86267777a31a5b5..707755f59a8d617239f6f6806c2cfcef0176ae1c 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.mod/member_swap.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.mod/member_swap.pass.cpp
@@ -25,7 +25,7 @@ struct mutex
 
 mutex m;
 
-int main()
+int main(int, char**)
 {
     std::unique_lock<mutex> lk1(m);
     std::unique_lock<mutex> lk2;
@@ -34,4 +34,6 @@ int main()
     assert(lk1.owns_lock() == false);
     assert(lk2.mutex() == &m);
     assert(lk2.owns_lock() == true);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.mod/nonmember_swap.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.mod/nonmember_swap.pass.cpp
index ea99ba9e5ff3ba339bf803948f725d8e1b8923c9..1c05657d6babdf083fdf772ebee74dc25ebdfee5 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.mod/nonmember_swap.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.mod/nonmember_swap.pass.cpp
@@ -26,7 +26,7 @@ struct mutex
 
 mutex m;
 
-int main()
+int main(int, char**)
 {
     std::unique_lock<mutex> lk1(m);
     std::unique_lock<mutex> lk2;
@@ -35,4 +35,6 @@ int main()
     assert(lk1.owns_lock() == false);
     assert(lk2.mutex() == &m);
     assert(lk2.owns_lock() == true);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.mod/release.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.mod/release.pass.cpp
index 9dc9ec3a1ab63c052f18de88f70a014ee4d0ff1d..9751149b9bd915b3063ea8b659aa722e264cf250 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.mod/release.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.mod/release.pass.cpp
@@ -30,7 +30,7 @@ int mutex::unlock_count = 0;
 
 mutex m;
 
-int main()
+int main(int, char**)
 {
     std::unique_lock<mutex> lk(m);
     assert(lk.mutex() == &m);
@@ -42,4 +42,6 @@ int main()
     assert(lk.owns_lock() == false);
     assert(mutex::lock_count == 1);
     assert(mutex::unlock_count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.obs/mutex.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.obs/mutex.pass.cpp
index 6e6fb6b76ff5eff80214d17bb1bcd385167d6349..899f965dfe18ad3fab2bfd416a17187e6c99f4eb 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.obs/mutex.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.obs/mutex.pass.cpp
@@ -19,7 +19,7 @@
 
 std::mutex m;
 
-int main()
+int main(int, char**)
 {
     std::unique_lock<std::mutex> lk0;
     assert(lk0.mutex() == nullptr);
@@ -27,4 +27,6 @@ int main()
     assert(lk1.mutex() == &m);
     lk1.unlock();
     assert(lk1.mutex() == &m);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.obs/op_bool.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.obs/op_bool.pass.cpp
index 184bc71f5b7cb7e8a91678d5e5f6c27d70402805..1affe8deb19dd4ec553005d1893e06207a112052 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.obs/op_bool.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.obs/op_bool.pass.cpp
@@ -19,7 +19,7 @@
 
 std::mutex m;
 
-int main()
+int main(int, char**)
 {
     std::unique_lock<std::mutex> lk0;
     assert(static_cast<bool>(lk0) == false);
@@ -27,4 +27,6 @@ int main()
     assert(static_cast<bool>(lk1) == true);
     lk1.unlock();
     assert(static_cast<bool>(lk1) == false);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.obs/owns_lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.obs/owns_lock.pass.cpp
index 68f944e2663b647c5e4bd95de0f603d9ac692caa..2c5496b294b348259266aa3dbf9bcf74b6f96616 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.obs/owns_lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.obs/owns_lock.pass.cpp
@@ -19,7 +19,7 @@
 
 std::mutex m;
 
-int main()
+int main(int, char**)
 {
     std::unique_lock<std::mutex> lk0;
     assert(lk0.owns_lock() == false);
@@ -27,4 +27,6 @@ int main()
     assert(lk1.owns_lock() == true);
     lk1.unlock();
     assert(lk1.owns_lock() == false);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/types.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/types.pass.cpp
index 44b1265e7ead65c686a9007e52b9be4f2cfbff49..7dc093ac6390a2d8bb07de012cdb4f4cd5ea4ce2 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/types.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/types.pass.cpp
@@ -21,8 +21,10 @@
 #include <mutex>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::unique_lock<std::mutex>::mutex_type,
                    std::mutex>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.lock/types.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.lock/types.pass.cpp
index 8d6a1fbcef9a77ec92dd3218c9518d45f3cd774a..150d9b4aafc61a9c9e16e5e5640fc9106539f713 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.lock/types.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.lock/types.pass.cpp
@@ -21,7 +21,7 @@
 #include <mutex>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     typedef std::defer_lock_t T1;
     typedef std::try_to_lock_t T2;
@@ -30,4 +30,6 @@ int main()
     T1 t1 = std::defer_lock; ((void)t1);
     T2 t2 = std::try_to_lock; ((void)t2);
     T3 t3 = std::adopt_lock; ((void)t3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/nothing_to_do.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.general/nothing_to_do.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.general/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.general/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.general/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/nothing_to_do.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.class/assign.fail.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.class/assign.fail.cpp
index d2d34a289ead24983349d41eaf4b3a5d839b9dcf..ba09ed1a706ea7c4ff8b474a4d316d2592ffbe66 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.class/assign.fail.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.class/assign.fail.cpp
@@ -14,9 +14,11 @@
 
 #include <mutex>
 
-int main()
+int main(int, char**)
 {
     std::mutex m0;
     std::mutex m1;
     m1 = m0;
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.class/copy.fail.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.class/copy.fail.cpp
index 5e1f17dc186729802e72bd0f9d437a66f346e6c1..9edfb7267dee6fd01412082b40e9ec1562a87a5d 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.class/copy.fail.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.class/copy.fail.cpp
@@ -14,8 +14,10 @@
 
 #include <mutex>
 
-int main()
+int main(int, char**)
 {
     std::mutex m0;
     std::mutex m1(m0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.class/default.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.class/default.pass.cpp
index aa8a34b0735120ac9ae731dad1c4c93fa3e59da9..b5a608eeb0cecac1a2c2e4ddc9e5e288f9a20372 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.class/default.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.class/default.pass.cpp
@@ -17,8 +17,10 @@
 #include <mutex>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert(std::is_nothrow_default_constructible<std::mutex>::value, "");
     std::mutex m;
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.class/lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.class/lock.pass.cpp
index 912b647d3d2c6d4eaefb43d29d693a90dce64982..dcb4b8ff8591daa1a2f2825fa6196aaa39815532 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.class/lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.class/lock.pass.cpp
@@ -41,11 +41,13 @@ void f()
     assert(d < ms(50));  // within 50ms
 }
 
-int main()
+int main(int, char**)
 {
     m.lock();
     std::thread t(f);
     std::this_thread::sleep_for(ms(250));
     m.unlock();
     t.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.class/try_lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.class/try_lock.pass.cpp
index 9d3d53dab3139f2efca9a31662ba7de1d901ab1c..71221558331ac00b4ce36e0e276ed531ede99388 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.class/try_lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.class/try_lock.pass.cpp
@@ -41,11 +41,13 @@ void f()
     assert(d < ms(200));  // within 200ms
 }
 
-int main()
+int main(int, char**)
 {
     m.lock();
     std::thread t(f);
     std::this_thread::sleep_for(ms(250));
     m.unlock();
     t.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.recursive/assign.fail.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.recursive/assign.fail.cpp
index 613eae74de5e60012b78afe95e7f8fab63b60121..0cf3c5bca1e1b4e37b91d624f0ed1d5a72bfbfeb 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.recursive/assign.fail.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.recursive/assign.fail.cpp
@@ -14,9 +14,11 @@
 
 #include <mutex>
 
-int main()
+int main(int, char**)
 {
     std::recursive_mutex m0;
     std::recursive_mutex m1;
     m1 = m0;
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.recursive/copy.fail.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.recursive/copy.fail.cpp
index 812951b46ec888ee3f0a3bf39f1abb2eace043a1..454d7797373cace0b06d937481b5efc00e73ab35 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.recursive/copy.fail.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.recursive/copy.fail.cpp
@@ -14,8 +14,10 @@
 
 #include <mutex>
 
-int main()
+int main(int, char**)
 {
     std::recursive_mutex m0;
     std::recursive_mutex m1(m0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.recursive/default.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.recursive/default.pass.cpp
index 9c63a803703bbb60127b3a601806577a75a3018f..e32c92f0c97b8312a02f92e88249c53e5eb94d7c 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.recursive/default.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.recursive/default.pass.cpp
@@ -16,7 +16,9 @@
 
 #include <mutex>
 
-int main()
+int main(int, char**)
 {
     std::recursive_mutex m;
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.recursive/lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.recursive/lock.pass.cpp
index 0342b4c2cf2913056bb114dfabf0027839b4fa3c..f8744a9b750ea6fad5d62d1c6e3c19f622b9917e 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.recursive/lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.recursive/lock.pass.cpp
@@ -41,11 +41,13 @@ void f()
     assert(d < ms(200));  // within 200ms
 }
 
-int main()
+int main(int, char**)
 {
     m.lock();
     std::thread t(f);
     std::this_thread::sleep_for(ms(250));
     m.unlock();
     t.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.recursive/try_lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.recursive/try_lock.pass.cpp
index b5b256566f757b1af54681cca238779037f7eefc..092343fe752a416bebe6662d4848b5d31c7b7b02 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.recursive/try_lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.mutex.requirements.mutex/thread.mutex.recursive/try_lock.pass.cpp
@@ -43,11 +43,13 @@ void f()
     assert(d < ms(200));  // within 200ms
 }
 
-int main()
+int main(int, char**)
 {
     m.lock();
     std::thread t(f);
     std::this_thread::sleep_for(ms(250));
     m.unlock();
     t.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/nothing_to_do.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/assign.fail.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/assign.fail.cpp
index 6b589f97d9713697a17456f8b2f2c7595c0825a7..337fcdf08b497208da9d81d69e53091c07725994 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/assign.fail.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/assign.fail.cpp
@@ -17,9 +17,11 @@
 
 #include <shared_mutex>
 
-int main()
+int main(int, char**)
 {
     std::shared_mutex m0;
     std::shared_mutex m1;
     m1 = m0; // expected-error {{overload resolution selected deleted operator '='}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/copy.fail.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/copy.fail.cpp
index 0c4fb55f14a418c7985502ba516af7ebe35fe6d3..93d02885a5902527fead487d7f86f19d1254c192 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/copy.fail.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/copy.fail.cpp
@@ -17,8 +17,10 @@
 
 #include <shared_mutex>
 
-int main()
+int main(int, char**)
 {
     std::shared_mutex m0;
     std::shared_mutex m1(m0); // expected-error {{call to deleted constructor of 'std::shared_mutex'}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/default.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/default.pass.cpp
index ac8b9b076cbb7693eed0345db41e67793fe0cbed..ecd29b7485a74633873b508f13de7b989445cd94 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/default.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/default.pass.cpp
@@ -17,7 +17,9 @@
 
 #include <shared_mutex>
 
-int main()
+int main(int, char**)
 {
     std::shared_mutex m;
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/lock.pass.cpp
index 3eb434a8034501d1871322568392882718c64cc0..74c66d0f672b80ab0f590ae142499128c4740e21 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/lock.pass.cpp
@@ -53,11 +53,13 @@ void f()
     assert(d < Tolerance);  // within tolerance
 }
 
-int main()
+int main(int, char**)
 {
     m.lock();
     std::thread t(f);
     std::this_thread::sleep_for(WaitTime);
     m.unlock();
     t.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/lock_shared.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/lock_shared.pass.cpp
index 38be785c8677dbe2c0d1602800b2e83fc4debb24..7707af8d8b8feb54a19b63aea736f15a872a78e0 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/lock_shared.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/lock_shared.pass.cpp
@@ -65,7 +65,7 @@ void g()
 }
 
 
-int main()
+int main(int, char**)
 {
     m.lock();
     std::vector<std::thread> v;
@@ -84,4 +84,6 @@ int main()
     for (auto& t : v)
         t.join();
     q.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/try_lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/try_lock.pass.cpp
index fff58b1ff72d1c2ab18b50807dcda63ee15f5be4..09c7ad5f005f5722431959bccaa553f044083b31 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/try_lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/try_lock.pass.cpp
@@ -42,11 +42,13 @@ void f()
     assert(d < ms(200));  // within 200ms
 }
 
-int main()
+int main(int, char**)
 {
     m.lock();
     std::thread t(f);
     std::this_thread::sleep_for(ms(250));
     m.unlock();
     t.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/try_lock_shared.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/try_lock_shared.pass.cpp
index 26bf18868f6949552fbd73034591e6f8a6b94edb..b9538b5649757500a3a988fc859d59b7c686909f 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/try_lock_shared.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.shared_mutex.requirements/thread.shared_mutex.class/try_lock_shared.pass.cpp
@@ -46,7 +46,7 @@ void f()
 }
 
 
-int main()
+int main(int, char**)
 {
     m.lock();
     std::vector<std::thread> v;
@@ -56,4 +56,6 @@ int main()
     m.unlock();
     for (auto& t : v)
         t.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/nothing_to_do.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/assign.fail.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/assign.fail.cpp
index c710e0510f774a8fc0f1cc8086d147c5f349b113..483111db97e452f6bee78ece7943327e400f4f8c 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/assign.fail.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/assign.fail.cpp
@@ -15,9 +15,11 @@
 
 #include <shared_mutex>
 
-int main()
+int main(int, char**)
 {
     std::shared_timed_mutex m0;
     std::shared_timed_mutex m1;
     m1 = m0;
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/copy.fail.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/copy.fail.cpp
index dba5e3114173c78cbf88927c8dc781dcc4ebf7c3..7483b1f5193769ffb1f143d24ba6e1c45afc2ce1 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/copy.fail.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/copy.fail.cpp
@@ -15,8 +15,10 @@
 
 #include <shared_mutex>
 
-int main()
+int main(int, char**)
 {
     std::shared_timed_mutex m0;
     std::shared_timed_mutex m1(m0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/default.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/default.pass.cpp
index 8fe432fc19188395c86c8d50ff3344f14c4338e8..83b30b98dd91e57404e0e47bdff4d4739cd71791 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/default.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/default.pass.cpp
@@ -17,7 +17,9 @@
 
 #include <shared_mutex>
 
-int main()
+int main(int, char**)
 {
     std::shared_timed_mutex m;
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/lock.pass.cpp
index c3be2b616636f3994dda88c19930f4705f88fd71..56464b24005d9c2968885fb9e802e7e9c28931b0 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/lock.pass.cpp
@@ -55,11 +55,13 @@ void f()
     assert(d < ms(50));  // within 50ms
 }
 
-int main()
+int main(int, char**)
 {
     m.lock();
     std::thread t(f);
     std::this_thread::sleep_for(ms(250));
     m.unlock();
     t.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/lock_shared.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/lock_shared.pass.cpp
index 0702ba01c079dddfc6b28aa7facfc18828258d3c..08d35861e4708b5d6dd1c3ea71f2044f3a0d2c6e 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/lock_shared.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/lock_shared.pass.cpp
@@ -67,7 +67,7 @@ void g()
 }
 
 
-int main()
+int main(int, char**)
 {
     m.lock();
     std::vector<std::thread> v;
@@ -86,4 +86,6 @@ int main()
     for (auto& t : v)
         t.join();
     q.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock.pass.cpp
index 4927c3654b74323b2285234668da2bdd6d5f61b1..6b2d9a543e57eef29c8525b12aad0c44b03149f8 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock.pass.cpp
@@ -42,11 +42,13 @@ void f()
     assert(d < ms(200));  // within 200ms
 }
 
-int main()
+int main(int, char**)
 {
     m.lock();
     std::thread t(f);
     std::this_thread::sleep_for(ms(250));
     m.unlock();
     t.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_for.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_for.pass.cpp
index d2a24fb81cad55a69600451f33484dea72caf480..45fea3e96fc66f8b3dde53c89b553e6e222dcf29 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_for.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_for.pass.cpp
@@ -64,7 +64,7 @@ void f2()
     assert(d < Tolerance);  // within tolerance
 }
 
-int main()
+int main(int, char**)
 {
     {
         m.lock();
@@ -80,4 +80,6 @@ int main()
         m.unlock();
         t.join();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_shared.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_shared.pass.cpp
index 7e0886de44766f10185d1c7b06aa1ff1947179f4..830445af9a01d0f26f726bcee759b835c0b72a6a 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_shared.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_shared.pass.cpp
@@ -54,7 +54,7 @@ void f()
     assert(d < Tolerance);  // within tolerance
 }
 
-int main()
+int main(int, char**)
 {
     m.lock();
     std::vector<std::thread> v;
@@ -64,4 +64,6 @@ int main()
     m.unlock();
     for (auto& t : v)
         t.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_shared_for.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_shared_for.pass.cpp
index 250ff9be932eef13337b1661517b16de4753e305..d89e4aa8cfc59fbc8efbd267edccc9709aba4730 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_shared_for.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_shared_for.pass.cpp
@@ -64,7 +64,7 @@ void f2()
     assert(d < Tolerance);  // within 50ms
 }
 
-int main()
+int main(int, char**)
 {
     {
         m.lock();
@@ -86,4 +86,6 @@ int main()
         for (auto& t : v)
             t.join();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_shared_until.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_shared_until.pass.cpp
index de6c58463878e9470c9a9658f07026eb1ae8a751..5898fe41e054154b0b7b349802ba7b961cebb7db 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_shared_until.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_shared_until.pass.cpp
@@ -64,7 +64,7 @@ void f2()
     assert(d < Tolerance);  // within tolerance
 }
 
-int main()
+int main(int, char**)
 {
     {
         m.lock();
@@ -86,4 +86,6 @@ int main()
         for (auto& t : v)
             t.join();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_until.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_until.pass.cpp
index 40cdfe844001c41236f3359a064e9f2ddf82faa6..9539215c46fc9839d51d18037b723e34e03ce01c 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_until.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_until.pass.cpp
@@ -64,7 +64,7 @@ void f2()
     assert(d < Tolerance);  // within tolerance
 }
 
-int main()
+int main(int, char**)
 {
     {
         m.lock();
@@ -80,4 +80,6 @@ int main()
         m.unlock();
         t.join();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_until_deadlock_bug.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_until_deadlock_bug.pass.cpp
index fb766e1617a3eb76aa3ae4889c2d43019842cff4..865ab92545a6ff1b7a229ab614c7589563de678f 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_until_deadlock_bug.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.sharedtimedmutex.requirements/thread.sharedtimedmutex.class/try_lock_until_deadlock_bug.pass.cpp
@@ -47,7 +47,7 @@ void blocked_reader() {
   m.unlock_shared();
 }
 
-int main()
+int main(int, char**)
 {
   typedef std::chrono::steady_clock Clock;
 
@@ -66,4 +66,6 @@ int main()
   t1.join();
   t2.join();
   t3.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/nothing_to_do.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.class/assign.fail.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.class/assign.fail.cpp
index 902b5ec42a6a9d8a4ba28f493a9808b7fac1fd08..d0fabc678f26c716af4e03612bdf7e9f04e3da8d 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.class/assign.fail.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.class/assign.fail.cpp
@@ -14,9 +14,11 @@
 
 #include <mutex>
 
-int main()
+int main(int, char**)
 {
     std::timed_mutex m0;
     std::timed_mutex m1;
     m1 = m0;
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.class/copy.fail.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.class/copy.fail.cpp
index 803b330d6a9b6cc397aed08bee5a0d41dd6aa302..a3efb2feeeedaebb3dabec21319718bc65afdb49 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.class/copy.fail.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.class/copy.fail.cpp
@@ -14,8 +14,10 @@
 
 #include <mutex>
 
-int main()
+int main(int, char**)
 {
     std::timed_mutex m0;
     std::timed_mutex m1(m0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.class/default.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.class/default.pass.cpp
index aae979043bf1ac09077e4d997f69815f746fc793..c879f192ee18abf41e9d7b1dafe8a5b0374cf4c3 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.class/default.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.class/default.pass.cpp
@@ -16,7 +16,9 @@
 
 #include <mutex>
 
-int main()
+int main(int, char**)
 {
     std::timed_mutex m;
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.class/lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.class/lock.pass.cpp
index 7b351829ab41676721dd06857f0f2d6f8f535086..8ef3a83471bdedf4e1bc43c723a3bd68ae269f6b 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.class/lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.class/lock.pass.cpp
@@ -39,11 +39,13 @@ void f()
     assert(d < ms(50));  // within 50ms
 }
 
-int main()
+int main(int, char**)
 {
     m.lock();
     std::thread t(f);
     std::this_thread::sleep_for(ms(250));
     m.unlock();
     t.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.class/try_lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.class/try_lock.pass.cpp
index d61f62635e88cbd8d1d205504fdff7deaa16d9d3..7398b7f6d0b8d5c1c7abd6b66ccee81c6ce429b0 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.class/try_lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.class/try_lock.pass.cpp
@@ -41,11 +41,13 @@ void f()
     assert(d < ms(200));  // within 200ms
 }
 
-int main()
+int main(int, char**)
 {
     m.lock();
     std::thread t(f);
     std::this_thread::sleep_for(ms(250));
     m.unlock();
     t.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.class/try_lock_for.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.class/try_lock_for.pass.cpp
index 2e050d91702a41f37a9d0de17141903f91050b46..0103cdf64195e2d6d686d4a3cefb9d539c048b89 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.class/try_lock_for.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.class/try_lock_for.pass.cpp
@@ -47,7 +47,7 @@ void f2()
     assert(d < ms(50));  // within 50ms
 }
 
-int main()
+int main(int, char**)
 {
     {
         m.lock();
@@ -63,4 +63,6 @@ int main()
         m.unlock();
         t.join();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.class/try_lock_until.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.class/try_lock_until.pass.cpp
index adf711593c4213db51ce697fdebdb97e65982b0b..350bb767d48ea7be0e0bedb48eca55a55e3af5ca 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.class/try_lock_until.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.class/try_lock_until.pass.cpp
@@ -47,7 +47,7 @@ void f2()
     assert(d < ms(50));  // within 50ms
 }
 
-int main()
+int main(int, char**)
 {
     {
         m.lock();
@@ -63,4 +63,6 @@ int main()
         m.unlock();
         t.join();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.recursive/assign.fail.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.recursive/assign.fail.cpp
index e34b2b9980a461a310b00d8e8cd7e4818904ed23..44be06d6754133c383752c483a9e856111a58493 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.recursive/assign.fail.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.recursive/assign.fail.cpp
@@ -14,9 +14,11 @@
 
 #include <mutex>
 
-int main()
+int main(int, char**)
 {
     std::recursive_timed_mutex m0;
     std::recursive_timed_mutex m1;
     m1 = m0;
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.recursive/copy.fail.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.recursive/copy.fail.cpp
index cbdd2eb634af855bfb729475834fa7f598257422..154a0192d14db1e3b4f7eb272d4883ec155c5cb9 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.recursive/copy.fail.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.recursive/copy.fail.cpp
@@ -14,8 +14,10 @@
 
 #include <mutex>
 
-int main()
+int main(int, char**)
 {
     std::recursive_timed_mutex m0;
     std::recursive_timed_mutex m1(m0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.recursive/default.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.recursive/default.pass.cpp
index 98de22eccc8c838a14b579eef9d8cd5c9c11d784..ee6124c027b7ebe5d772f2119354bb52186f4681 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.recursive/default.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.recursive/default.pass.cpp
@@ -16,7 +16,9 @@
 
 #include <mutex>
 
-int main()
+int main(int, char**)
 {
     std::recursive_timed_mutex m;
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.recursive/lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.recursive/lock.pass.cpp
index aba747b95206b3b0c6f6eb6a740b064a9ddc52d6..adb54872e9bb1815cdb6cb79f4ba3fa77004f478 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.recursive/lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.recursive/lock.pass.cpp
@@ -43,11 +43,13 @@ void f()
     assert(d < ms(50));  // within 50ms
 }
 
-int main()
+int main(int, char**)
 {
     m.lock();
     std::thread t(f);
     std::this_thread::sleep_for(ms(250));
     m.unlock();
     t.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.recursive/try_lock.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.recursive/try_lock.pass.cpp
index 9d73bb57f332ebe96fc0cd273af3b37ba1c2f737..05b22c0deb1ff6e1f42ddbc8263e563a8d07804a 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.recursive/try_lock.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.recursive/try_lock.pass.cpp
@@ -43,11 +43,13 @@ void f()
     assert(d < ms(200));  // within 200ms
 }
 
-int main()
+int main(int, char**)
 {
     m.lock();
     std::thread t(f);
     std::this_thread::sleep_for(ms(250));
     m.unlock();
     t.join();
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.recursive/try_lock_for.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.recursive/try_lock_for.pass.cpp
index feab814953bec71b19f66acfaf75bc93e97d2548..9e5ad5ee9a5daeb39b108a2482405be26db21fe3 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.recursive/try_lock_for.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.recursive/try_lock_for.pass.cpp
@@ -49,7 +49,7 @@ void f2()
     assert(d < ns(50000000));  // within 50ms
 }
 
-int main()
+int main(int, char**)
 {
     {
         m.lock();
@@ -65,4 +65,6 @@ int main()
         m.unlock();
         t.join();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.recursive/try_lock_until.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.recursive/try_lock_until.pass.cpp
index b795315b28dc83afea24f57a351cba12335ff550..f6b9d106a1b76bce1ccc55c33bc7790623ba012b 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.recursive/try_lock_until.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.mutex.requirements/thread.timedmutex.requirements/thread.timedmutex.recursive/try_lock_until.pass.cpp
@@ -49,7 +49,7 @@ void f2()
     assert(d < ms(50));  // within 50ms
 }
 
-int main()
+int main(int, char**)
 {
     {
         m.lock();
@@ -65,4 +65,6 @@ int main()
         m.unlock();
         t.join();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.once/nothing_to_do.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.once/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.once/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.once/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.once/thread.once.callonce/call_once.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.once/thread.once.callonce/call_once.pass.cpp
index be5056e40f7bb73d30bea6cafb0316d3e4815964..398ee058c128e37eb603518129304681375f095d 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.once/thread.once.callonce/call_once.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.once/thread.once.callonce/call_once.pass.cpp
@@ -186,7 +186,7 @@ struct RefQual
 
 #endif // TEST_STD_VER >= 11
 
-int main()
+int main(int, char**)
 {
     // check basic functionality
     {
@@ -253,4 +253,6 @@ int main()
         assert(rq.rv_called == 1);
     }
 #endif  // TEST_STD_VER >= 11
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.once/thread.once.callonce/race.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.once/thread.once.callonce/race.pass.cpp
index ebba7f3d4f46c68b7421b2648203b4c414061989..511aa3e804b05da600dd38059ea00c3a8e6095dd 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.once/thread.once.callonce/race.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.once/thread.once.callonce/race.pass.cpp
@@ -37,11 +37,13 @@ void f0()
     assert(global == 1);
 }
 
-int main()
+int main(int, char**)
 {
     std::thread t0(f0);
     std::thread t1(f0);
     t0.join();
     t1.join();
     assert(global == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.once/thread.once.onceflag/assign.fail.cpp b/libcxx/test/std/thread/thread.mutex/thread.once/thread.once.onceflag/assign.fail.cpp
index dd6fe09c3b81a116892b8427f7a497ff1361eece..40d408d54ce33f82d2931ee75c6026ada65a8a67 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.once/thread.once.onceflag/assign.fail.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.once/thread.once.onceflag/assign.fail.cpp
@@ -14,9 +14,11 @@
 
 #include <mutex>
 
-int main()
+int main(int, char**)
 {
     std::once_flag f;
     std::once_flag f2;
     f2 = f;
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.once/thread.once.onceflag/copy.fail.cpp b/libcxx/test/std/thread/thread.mutex/thread.once/thread.once.onceflag/copy.fail.cpp
index ca428ffb438e858e4f1db5b21bb4296d37327f2b..9b7c19a96720d03109a5dbce7b90bb24542a5dde 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.once/thread.once.onceflag/copy.fail.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.once/thread.once.onceflag/copy.fail.cpp
@@ -14,8 +14,10 @@
 
 #include <mutex>
 
-int main()
+int main(int, char**)
 {
     std::once_flag f;
     std::once_flag f2(f);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.mutex/thread.once/thread.once.onceflag/default.pass.cpp b/libcxx/test/std/thread/thread.mutex/thread.once/thread.once.onceflag/default.pass.cpp
index 4a1655ffeba48231f2a631316a6a7a8f9f300845..28d93dc7f383fe045441afd8002a71d38c641f41 100644
--- a/libcxx/test/std/thread/thread.mutex/thread.once/thread.once.onceflag/default.pass.cpp
+++ b/libcxx/test/std/thread/thread.mutex/thread.once/thread.once.onceflag/default.pass.cpp
@@ -15,7 +15,7 @@
 #include <mutex>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::once_flag f;
@@ -27,4 +27,6 @@ int main()
     (void)f;
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.req/nothing_to_do.pass.cpp b/libcxx/test/std/thread/thread.req/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/thread/thread.req/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/thread/thread.req/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.req/thread.req.exception/nothing_to_do.pass.cpp b/libcxx/test/std/thread/thread.req/thread.req.exception/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/thread/thread.req/thread.req.exception/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/thread/thread.req/thread.req.exception/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.req/thread.req.lockable/nothing_to_do.pass.cpp b/libcxx/test/std/thread/thread.req/thread.req.lockable/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/thread/thread.req/thread.req.lockable/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/thread/thread.req/thread.req.lockable/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.req/thread.req.lockable/thread.req.lockable.basic/nothing_to_do.pass.cpp b/libcxx/test/std/thread/thread.req/thread.req.lockable/thread.req.lockable.basic/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/thread/thread.req/thread.req.lockable/thread.req.lockable.basic/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/thread/thread.req/thread.req.lockable/thread.req.lockable.basic/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.req/thread.req.lockable/thread.req.lockable.general/nothing_to_do.pass.cpp b/libcxx/test/std/thread/thread.req/thread.req.lockable/thread.req.lockable.general/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/thread/thread.req/thread.req.lockable/thread.req.lockable.general/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/thread/thread.req/thread.req.lockable/thread.req.lockable.general/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.req/thread.req.lockable/thread.req.lockable.req/nothing_to_do.pass.cpp b/libcxx/test/std/thread/thread.req/thread.req.lockable/thread.req.lockable.req/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/thread/thread.req/thread.req.lockable/thread.req.lockable.req/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/thread/thread.req/thread.req.lockable/thread.req.lockable.req/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.req/thread.req.lockable/thread.req.lockable.timed/nothing_to_do.pass.cpp b/libcxx/test/std/thread/thread.req/thread.req.lockable/thread.req.lockable.timed/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/thread/thread.req/thread.req.lockable/thread.req.lockable.timed/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/thread/thread.req/thread.req.lockable/thread.req.lockable.timed/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.req/thread.req.native/nothing_to_do.pass.cpp b/libcxx/test/std/thread/thread.req/thread.req.native/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/thread/thread.req/thread.req.native/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/thread/thread.req/thread.req.native/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.req/thread.req.paramname/nothing_to_do.pass.cpp b/libcxx/test/std/thread/thread.req/thread.req.paramname/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/thread/thread.req/thread.req.paramname/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/thread/thread.req/thread.req.paramname/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.req/thread.req.timing/nothing_to_do.pass.cpp b/libcxx/test/std/thread/thread.req/thread.req.timing/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/thread/thread.req/thread.req.timing/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/thread/thread.req/thread.req.timing/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.algorithm/swap.pass.cpp b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.algorithm/swap.pass.cpp
index 64a41368627347a1fe5e76049190a04e6611369b..68f20d7532b5c59cb7729290451010752f21e1be 100644
--- a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.algorithm/swap.pass.cpp
+++ b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.algorithm/swap.pass.cpp
@@ -41,7 +41,7 @@ public:
 int G::n_alive = 0;
 bool G::op_run = false;
 
-int main()
+int main(int, char**)
 {
     {
         G g;
@@ -54,4 +54,6 @@ int main()
         assert(t1.get_id() == id0);
         t1.join();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.assign/copy.fail.cpp b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.assign/copy.fail.cpp
index 1afaaf7bd612853abd25db91ad9ed7be772993cc..e67ceea5db619b49f9b509217e00607dfdb3c914 100644
--- a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.assign/copy.fail.cpp
+++ b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.assign/copy.fail.cpp
@@ -40,11 +40,13 @@ public:
 int G::n_alive = 0;
 bool G::op_run = false;
 
-int main()
+int main(int, char**)
 {
     {
         std::thread t0(G());
         std::thread t1;
         t1 = t0;
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.assign/move.pass.cpp b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.assign/move.pass.cpp
index e2f3d38fc065e443703b0486166ab8a0fdc86525..cbc32c8c2ce1d44e04095deb789570d3d26274c2 100644
--- a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.assign/move.pass.cpp
+++ b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.assign/move.pass.cpp
@@ -41,7 +41,7 @@ public:
 int G::n_alive = 0;
 bool G::op_run = false;
 
-int main()
+int main(int, char**)
 {
     {
         assert(G::n_alive == 0);
@@ -59,4 +59,6 @@ int main()
         assert(G::n_alive == 0);
         assert(G::op_run);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.assign/move2.pass.cpp b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.assign/move2.pass.cpp
index 9a4d6e910207f33e367795f9de3c38f29a80d427..81c6d77e8a719da56bcecf9cb75231d9e14ccd21 100644
--- a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.assign/move2.pass.cpp
+++ b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.assign/move2.pass.cpp
@@ -51,7 +51,7 @@ void f1()
     std::_Exit(0);
 }
 
-int main()
+int main(int, char**)
 {
     std::set_terminate(f1);
     {
@@ -61,4 +61,6 @@ int main()
         t0 = std::move(t1);
         assert(false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.constr/F.pass.cpp b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.constr/F.pass.cpp
index af2450f182f524744ce0d2f43a88a89d8b5d198b..13c69180a4d67664cb27fb775c03bf6f3a936179 100644
--- a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.constr/F.pass.cpp
+++ b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.constr/F.pass.cpp
@@ -144,7 +144,7 @@ void test_throwing_new_during_thread_creation() {
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test_throwing_new_during_thread_creation();
     {
@@ -200,4 +200,6 @@ int main()
         t.join();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.constr/constr.fail.cpp b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.constr/constr.fail.cpp
index c24b0413b2086d7f6a5cc8fa4c1c53d2a303d3c4..26231373f80c3e3ff5c7fcc7da1caef65edbf84c 100644
--- a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.constr/constr.fail.cpp
+++ b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.constr/constr.fail.cpp
@@ -18,8 +18,10 @@
 #include <thread>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     volatile std::thread t1;
     std::thread t2 ( t1, 1, 2.0 );
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.constr/copy.fail.cpp b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.constr/copy.fail.cpp
index 4a2e6f0d44b31f62609f2d5794d587fa4ad7a4e1..2a3632cd42fb68a3f3baaf7a4303785a5a86c666 100644
--- a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.constr/copy.fail.cpp
+++ b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.constr/copy.fail.cpp
@@ -48,7 +48,7 @@ public:
 int G::n_alive = 0;
 bool G::op_run = false;
 
-int main()
+int main(int, char**)
 {
     {
         assert(G::n_alive == 0);
@@ -62,4 +62,6 @@ int main()
         assert(G::n_alive == 0);
         assert(G::op_run);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.constr/default.pass.cpp b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.constr/default.pass.cpp
index d635470db312388e4b5d917451aebf72f1961424..135d3ceba9997ea994eafa34fc9ea9e3a8b73321 100644
--- a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.constr/default.pass.cpp
+++ b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.constr/default.pass.cpp
@@ -17,8 +17,10 @@
 #include <thread>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::thread t;
     assert(t.get_id() == std::thread::id());
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.constr/move.pass.cpp b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.constr/move.pass.cpp
index 7e34729b3a74753710ed61bcce5bfeda259271d1..25703b2c3cabe7fe42a2effdfc875877db05124a 100644
--- a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.constr/move.pass.cpp
+++ b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.constr/move.pass.cpp
@@ -50,7 +50,7 @@ public:
 int G::n_alive = 0;
 bool G::op_run = false;
 
-int main()
+int main(int, char**)
 {
     {
         G g;
@@ -66,4 +66,6 @@ int main()
         assert(G::op_run);
     }
     assert(G::n_alive == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.destr/dtor.pass.cpp b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.destr/dtor.pass.cpp
index 202d61b8f227e09d0bb55872732b5c96b9b3ee2b..320b4459b94c60600dcb08de34f23f8f695d45f8 100644
--- a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.destr/dtor.pass.cpp
+++ b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.destr/dtor.pass.cpp
@@ -47,7 +47,7 @@ void f1()
     std::_Exit(0);
 }
 
-int main()
+int main(int, char**)
 {
     std::set_terminate(f1);
     {
@@ -60,4 +60,6 @@ int main()
         }
     }
     assert(false);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/assign.pass.cpp b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/assign.pass.cpp
index 4447600486a745648b591c4927d5a1e66849dd3f..fb4b7eb5ae054fe147f759fa2331832aed9e0bb0 100644
--- a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/assign.pass.cpp
+++ b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/assign.pass.cpp
@@ -17,7 +17,7 @@
 #include <thread>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::thread::id id0;
     std::thread::id id1;
@@ -25,4 +25,6 @@ int main()
     assert(id1 == id0);
     id1 = std::this_thread::get_id();
     assert(id1 != id0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/copy.pass.cpp b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/copy.pass.cpp
index 52d4f2cf377db5166c1f747ea873ec13dbe0899b..f95617b4f53caf4a838acf26db557ecbb2dd3a2d 100644
--- a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/copy.pass.cpp
+++ b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/copy.pass.cpp
@@ -17,9 +17,11 @@
 #include <thread>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::thread::id id0;
     std::thread::id id1 = id0;
     assert(id1 == id0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/default.pass.cpp b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/default.pass.cpp
index a9778f047d2d96e1c8bc4db2ca89024c6cc49a45..32a083ca8aae6ca4cd48f05ce718144d79884404 100644
--- a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/default.pass.cpp
+++ b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/default.pass.cpp
@@ -17,8 +17,10 @@
 #include <thread>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::thread::id id;
     assert(id == std::thread::id());
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/enabled_hashes.pass.cpp b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/enabled_hashes.pass.cpp
index 7a2fa869d627bfa26166670e4dc95c67c39c6143..3858508e1c9a1c98c240467af74e6e45f4b21da1 100644
--- a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/enabled_hashes.pass.cpp
+++ b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/enabled_hashes.pass.cpp
@@ -18,9 +18,11 @@
 
 #include "poisoned_hash_helper.hpp"
 
-int main() {
+int main(int, char**) {
   test_library_hash_specializations_available();
   {
     test_hash_enabled_for_type<std::thread::id>();
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/eq.pass.cpp b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/eq.pass.cpp
index cf89066a5099f941d0a144b0cbf73794d65e0c26..5c557fddc7f91f826587f7275ad7c5bc5c2ba2f9 100644
--- a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/eq.pass.cpp
+++ b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/eq.pass.cpp
@@ -18,7 +18,7 @@
 #include <thread>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::thread::id id0;
     std::thread::id id1;
@@ -28,4 +28,6 @@ int main()
     id1 = std::this_thread::get_id();
     assert(!(id1 == id0));
     assert( (id1 != id0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/lt.pass.cpp b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/lt.pass.cpp
index 69ea217b506150ed7571144b53999fbb04d51eb2..8af73045a792ed7c8774d5933041da9b280e3d18 100644
--- a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/lt.pass.cpp
+++ b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/lt.pass.cpp
@@ -20,7 +20,7 @@
 #include <thread>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::thread::id id0;
     std::thread::id id1;
@@ -39,4 +39,6 @@ int main()
       assert( (id0 >  id2));
       assert( (id0 >= id2));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/stream.pass.cpp b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/stream.pass.cpp
index d07f26b169837ff52761a024496e38656dab8d5d..a1541c12e2293d1450a26f4be5dd1aeebb7f4f9a 100644
--- a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/stream.pass.cpp
+++ b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/stream.pass.cpp
@@ -20,9 +20,11 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::thread::id id0 = std::this_thread::get_id();
     std::ostringstream os;
     os << id0;
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/thread_id.pass.cpp b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/thread_id.pass.cpp
index 325c0bfebd492b401377b2b8aa858dd0861bd2fe..80bcbf97c1dccfc4547db075b96aa19c40aedd5b 100644
--- a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/thread_id.pass.cpp
+++ b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/thread_id.pass.cpp
@@ -24,7 +24,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     std::thread::id id1;
     std::thread::id id2 = std::this_thread::get_id();
@@ -34,4 +34,6 @@ int main()
     ASSERT_NOEXCEPT(H()(id2));
     H h;
     assert(h(id1) != h(id2));
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.member/detach.pass.cpp b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.member/detach.pass.cpp
index 8debe7770dd1f519ec3b3cad47ec48425d5311b7..bf72e3437a47330a8a83e0e2b827d020789eab01 100644
--- a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.member/detach.pass.cpp
+++ b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.member/detach.pass.cpp
@@ -61,7 +61,7 @@ bool G::op_run = false;
 
 void foo() {}
 
-int main()
+int main(int, char**)
 {
     {
         G g;
@@ -86,4 +86,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.member/get_id.pass.cpp b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.member/get_id.pass.cpp
index 99cdec9134c9273d836eccacb39624406310de3a..006bc1e65c49d5b730d5c3c3d2adcd0b6ff95902 100644
--- a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.member/get_id.pass.cpp
+++ b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.member/get_id.pass.cpp
@@ -41,7 +41,7 @@ public:
 int G::n_alive = 0;
 bool G::op_run = false;
 
-int main()
+int main(int, char**)
 {
     {
         G g;
@@ -54,4 +54,6 @@ int main()
         assert(t1.get_id() == std::thread::id());
         t0.join();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.member/join.pass.cpp b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.member/join.pass.cpp
index c21de04ea346d53ee7124f32acfcae3646629e4e..b64a111c6be741981514004bdf586f17a7b43b75 100644
--- a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.member/join.pass.cpp
+++ b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.member/join.pass.cpp
@@ -46,7 +46,7 @@ bool G::op_run = false;
 
 void foo() {}
 
-int main()
+int main(int, char**)
 {
     {
         G g;
@@ -73,4 +73,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.member/joinable.pass.cpp b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.member/joinable.pass.cpp
index 3db473ab181de2ba9ac7b6004c7ee01aa519abdb..6f1308cbad097ae372af5548d8b653a74b80bb18 100644
--- a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.member/joinable.pass.cpp
+++ b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.member/joinable.pass.cpp
@@ -41,7 +41,7 @@ public:
 int G::n_alive = 0;
 bool G::op_run = false;
 
-int main()
+int main(int, char**)
 {
     {
         G g;
@@ -50,4 +50,6 @@ int main()
         t0.join();
         assert(!t0.joinable());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.member/swap.pass.cpp b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.member/swap.pass.cpp
index 66c810b1b7e2479348e093c56e67be85315c202d..f43805d7fe6f9e1286cf5fddbf24d4dd1e88abab 100644
--- a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.member/swap.pass.cpp
+++ b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.member/swap.pass.cpp
@@ -41,7 +41,7 @@ public:
 int G::n_alive = 0;
 bool G::op_run = false;
 
-int main()
+int main(int, char**)
 {
     {
         G g;
@@ -54,4 +54,6 @@ int main()
         assert(t1.get_id() == id0);
         t1.join();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.static/hardware_concurrency.pass.cpp b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.static/hardware_concurrency.pass.cpp
index 3500f2c169ac64448c36b40afbd6fe26ecdfa552..5493f27a4940ebfb3efb3c2167fcdd8ef69684f9 100644
--- a/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.static/hardware_concurrency.pass.cpp
+++ b/libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.static/hardware_concurrency.pass.cpp
@@ -17,7 +17,9 @@
 #include <thread>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert(std::thread::hardware_concurrency() > 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.threads/thread.thread.this/get_id.pass.cpp b/libcxx/test/std/thread/thread.threads/thread.thread.this/get_id.pass.cpp
index 864518dd8ffb08a5d7db16fec8a54cf1cc7be42a..1bf46cdb54f4bef19778678ebd7f478f31a37206 100644
--- a/libcxx/test/std/thread/thread.threads/thread.thread.this/get_id.pass.cpp
+++ b/libcxx/test/std/thread/thread.threads/thread.thread.this/get_id.pass.cpp
@@ -15,8 +15,10 @@
 #include <thread>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::thread::id id = std::this_thread::get_id();
     assert(id != std::thread::id());
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.threads/thread.thread.this/sleep_for_tested_elsewhere.pass.cpp b/libcxx/test/std/thread/thread.threads/thread.thread.this/sleep_for_tested_elsewhere.pass.cpp
index 59791c84cdb85104936614a7ce118c1e7a4d30e2..7c8552ea865398bae8ae31f8b8c138c91da16c37 100644
--- a/libcxx/test/std/thread/thread.threads/thread.thread.this/sleep_for_tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/thread/thread.threads/thread.thread.this/sleep_for_tested_elsewhere.pass.cpp
@@ -16,6 +16,8 @@
 // is therefore non-standard. For this reason the test lives under the 'libcxx'
 // subdirectory.
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.threads/thread.thread.this/sleep_until.pass.cpp b/libcxx/test/std/thread/thread.threads/thread.thread.this/sleep_until.pass.cpp
index 5fbaf9d877322c308afafe41457c7d777ba8039a..c73144db0c15df4af9a9a0c127f8460ab5211904 100644
--- a/libcxx/test/std/thread/thread.threads/thread.thread.this/sleep_until.pass.cpp
+++ b/libcxx/test/std/thread/thread.threads/thread.thread.this/sleep_until.pass.cpp
@@ -18,7 +18,7 @@
 #include <cstdlib>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::system_clock Clock;
     typedef Clock::time_point time_point;
@@ -30,4 +30,6 @@ int main()
     std::chrono::nanoseconds err = 5 * ms / 100;
     // The time slept is within 5% of 500ms
     assert(std::abs(ns.count()) < err.count());
+
+  return 0;
 }
diff --git a/libcxx/test/std/thread/thread.threads/thread.thread.this/yield.pass.cpp b/libcxx/test/std/thread/thread.threads/thread.thread.this/yield.pass.cpp
index 5c1caa0cbe0de8fe7784ba277c9ceb567b399f03..6f772b5c2860c159d97cc6f9e9f2541af3e98274 100644
--- a/libcxx/test/std/thread/thread.threads/thread.thread.this/yield.pass.cpp
+++ b/libcxx/test/std/thread/thread.threads/thread.thread.this/yield.pass.cpp
@@ -15,7 +15,9 @@
 #include <thread>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::this_thread::yield();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.cnstr/allocs.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.cnstr/allocs.pass.cpp
index 6ea9a8ec8beb351f1abed93bb1a032b88b1df4a6..961eda3ac8f06e85c8869cc8b651ba1dcacabcf7 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.cnstr/allocs.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.cnstr/allocs.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "allocators.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::scoped_allocator_adaptor<A1<int>> A;
@@ -113,4 +113,6 @@ int main()
              std::scoped_allocator_adaptor<A1<int>>,
              std::scoped_allocator_adaptor<A2<int>>>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.cnstr/converting_copy.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.cnstr/converting_copy.pass.cpp
index c1460603486f51c0f934457ae14691184617706d..d3734cae10e9a8f59781e2794148e5da42e8b7f4 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.cnstr/converting_copy.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.cnstr/converting_copy.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "allocators.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::scoped_allocator_adaptor<A1<double>> B;
@@ -64,4 +64,6 @@ int main()
         assert(a2 == a1);
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.cnstr/converting_move.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.cnstr/converting_move.pass.cpp
index 99f0e38fc853d1da5972e5ba7e93759423f109f9..427e299578802e9c0a02e0b74871a6c51cb3bd2d 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.cnstr/converting_move.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.cnstr/converting_move.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "allocators.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::scoped_allocator_adaptor<A1<double>> B;
@@ -69,4 +69,6 @@ int main()
         assert(A3<int>::move_called == true);
         assert(a2 == a1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.cnstr/copy.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.cnstr/copy.pass.cpp
index 38878e234e9217ca6ca81da2d23ff44eb7c36178..69b767b909e2a8c4a21c953ddffa484d1d5ebf10 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.cnstr/copy.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.cnstr/copy.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "allocators.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::scoped_allocator_adaptor<A1<int>> A;
@@ -64,4 +64,6 @@ int main()
         assert(A3<int>::move_called == false);
         assert(a2 == a1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.cnstr/default.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.cnstr/default.pass.cpp
index ac27f8b5465040d0ae5cbce94932fbb01147fa22..fdf21cec3e08c7bae64955469a53d35d10458b7a 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.cnstr/default.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.cnstr/default.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "allocators.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::scoped_allocator_adaptor<A1<int>> A;
@@ -53,4 +53,6 @@ int main()
         assert(A3<int>::move_called == false);
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/allocate_size.fail.cpp b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/allocate_size.fail.cpp
index 7b093826a852555d7c9981bd3dc6a0308f0b5f72..6d644db85e8c560cf1d7b151b7b190cc6b0b784c 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/allocate_size.fail.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/allocate_size.fail.cpp
@@ -21,8 +21,10 @@
 
 #include "allocators.h"
 
-int main()
+int main(int, char**)
 {
     std::scoped_allocator_adaptor<A1<int>> a;
     a.allocate(10);  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/allocate_size.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/allocate_size.pass.cpp
index 057541dd0993ecb5aafe1782637855232e8ba40a..05a1649e4a6ddd598b0fdd06b073d6f360926ad2 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/allocate_size.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/allocate_size.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "allocators.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::scoped_allocator_adaptor<A1<int>> A;
@@ -44,4 +44,6 @@ int main()
         assert(A1<int>::allocate_called == true);
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/allocate_size_hint.fail.cpp b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/allocate_size_hint.fail.cpp
index ffc59b800419bde396902c8751372abfafe190a4..7cf3d41090964039bbca161e5dbe11979504927e 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/allocate_size_hint.fail.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/allocate_size_hint.fail.cpp
@@ -21,8 +21,10 @@
 
 #include "allocators.h"
 
-int main()
+int main(int, char**)
 {
     std::scoped_allocator_adaptor<A1<int>> a;
     a.allocate(10, (const void*)0); // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/allocate_size_hint.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/allocate_size_hint.pass.cpp
index afe3e40d9f11326fba64f765712dcd9900697cd3..db9338d31b861ffb66bb40d6a87bfcce2a7254c6 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/allocate_size_hint.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/allocate_size_hint.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "allocators.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::scoped_allocator_adaptor<A1<int>> A;
@@ -65,4 +65,6 @@ int main()
         assert(a.allocate(10, (const void*)20) == (int*)20);
         assert(A2<int>::allocate_called == true);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/construct.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/construct.pass.cpp
index 6e02326fa4b6ff7b5e1f5fb533de4f5fd9430922..97ae33d9157aee6470d59014333a21a510c5e9aa 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/construct.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/construct.pass.cpp
@@ -110,7 +110,7 @@ struct F
 
 bool F::constructed = false;
 
-int main()
+int main(int, char**)
 {
 
     {
@@ -184,4 +184,6 @@ int main()
         assert(A3<F>::constructed);
         s->~S();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/construct_pair.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/construct_pair.pass.cpp
index 85fdd38f00daab44ca23c301d8506481d13e5fef..7aa45f05add9dab7eb31e3df421ae9f57abe7881 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/construct_pair.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/construct_pair.pass.cpp
@@ -135,7 +135,9 @@ void test_with_inner_alloc()
         std::free(ptr);
     }
 }
-int main() {
+int main(int, char**) {
     test_no_inner_alloc();
     test_with_inner_alloc();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/construct_pair_const_lvalue_pair.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/construct_pair_const_lvalue_pair.pass.cpp
index 30fea45b0215de570d0fdba766161746766cbc66..d1a03bc05fce003831d763e1236c343ba9f74494 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/construct_pair_const_lvalue_pair.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/construct_pair_const_lvalue_pair.pass.cpp
@@ -151,7 +151,9 @@ void test_with_inner_alloc()
         std::free(ptr);
     }
 }
-int main() {
+int main(int, char**) {
     test_no_inner_alloc();
     test_with_inner_alloc();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/construct_pair_piecewise.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/construct_pair_piecewise.pass.cpp
index c6e13bc1839da6a38f14c40910ce62f79c2187c7..14f413bd867159798e594fc8274837d5bb2a338e 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/construct_pair_piecewise.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/construct_pair_piecewise.pass.cpp
@@ -152,7 +152,9 @@ void test_with_inner_alloc()
         std::free(ptr);
     }
 }
-int main() {
+int main(int, char**) {
     test_no_inner_alloc();
     test_with_inner_alloc();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/construct_pair_rvalue.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/construct_pair_rvalue.pass.cpp
index 243b9e9979e3436e8d885bf39ea4d97bc8c48274..c26b4652cc49055ec8add743290797e1b15e83fe 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/construct_pair_rvalue.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/construct_pair_rvalue.pass.cpp
@@ -151,7 +151,9 @@ void test_with_inner_alloc()
         std::free(ptr);
     }
 }
-int main() {
+int main(int, char**) {
     test_no_inner_alloc();
     test_with_inner_alloc();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/construct_pair_values.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/construct_pair_values.pass.cpp
index acbe241e7c69e912b5a175594e880c8c5692056f..7a4b14956f034cc5e7fc411e6f09efeef5dbed90 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/construct_pair_values.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/construct_pair_values.pass.cpp
@@ -143,7 +143,9 @@ void test_with_inner_alloc()
         std::free(ptr);
     }
 }
-int main() {
+int main(int, char**) {
     test_no_inner_alloc();
     test_with_inner_alloc();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/construct_type.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/construct_type.pass.cpp
index 6a65d2ac6a037ca56da30c6e96df27f4446d8f4f..e93f37f412e5b55fa94d750f742beb8bace68c7f 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/construct_type.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/construct_type.pass.cpp
@@ -125,8 +125,10 @@ void test_bullet_three() {
     POuter.reset();
 }
 
-int main() {
+int main(int, char**) {
     test_bullet_one();
     test_bullet_two();
     test_bullet_three();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/deallocate.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/deallocate.pass.cpp
index e5c17edaf12b8e503191f7b4b23c98f637678410..425f00ad4f43da93a0888479b4c0f4e27ad85e11 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/deallocate.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/deallocate.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "allocators.h"
 
-int main()
+int main(int, char**)
 {
 
     {
@@ -42,4 +42,6 @@ int main()
         assert((A1<int>::deallocate_called == std::pair<int*, std::size_t>((int*)10, 20)));
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/destroy.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/destroy.pass.cpp
index 02c7afe4a1411e497065e08f783adb3437b16b82..50c9d24f07d3b6f834e143a0827e1c4c1d1fa96e 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/destroy.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/destroy.pass.cpp
@@ -31,7 +31,7 @@ struct B
 
 bool B::constructed = false;
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::scoped_allocator_adaptor<A1<B>> A;
@@ -65,4 +65,6 @@ int main()
         assert(A3<S>::destroy_called);
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/inner_allocator.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/inner_allocator.pass.cpp
index ad0f2e2951f137ded720228d67c12aa6be70497f..7e73939f8ee05a0b2da15bf826dff3e78e49b988 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/inner_allocator.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/inner_allocator.pass.cpp
@@ -21,7 +21,7 @@
 
 #include "allocators.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::scoped_allocator_adaptor<A1<int>> A;
@@ -40,4 +40,6 @@ int main()
             std::scoped_allocator_adaptor<A2<int>, A3<int>>(A2<int>(6), A3<int>(8))));
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/max_size.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/max_size.pass.cpp
index 51a9f811786b35e1227c0670190a2b71f94a9ff4..de9cf4d0cad752c857fffd4df9a12b2bd03ba7d0 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/max_size.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/max_size.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "allocators.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::scoped_allocator_adaptor<A1<int>> A;
@@ -38,4 +38,6 @@ int main()
         assert(a.max_size() == 200);
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/outer_allocator.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/outer_allocator.pass.cpp
index ccea2b2c0e1215293b227ce3469d1b9c8e2a62f3..9a90d17c0c6bf40667cf8ee6f6ac44ddf15c4525 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/outer_allocator.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/outer_allocator.pass.cpp
@@ -21,7 +21,7 @@
 
 #include "allocators.h"
 
-int main()
+int main(int, char**)
 {
 
     {
@@ -39,4 +39,6 @@ int main()
         A a(A1<int>(5), A2<int>(6), A3<int>(8));
         assert(a.outer_allocator() == A1<int>(5));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/select_on_container_copy_construction.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/select_on_container_copy_construction.pass.cpp
index ef42207574f4a4793d1cad88c655c1c738717bff..8253fee5518d37bb661e904500f965b7704ecc28 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/select_on_container_copy_construction.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.members/select_on_container_copy_construction.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "allocators.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::scoped_allocator_adaptor<A1<int>> A;
@@ -50,4 +50,6 @@ int main()
         assert(a2.inner_allocator().inner_allocator().outer_allocator().id() == -1);
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.types/allocator_pointers.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.types/allocator_pointers.pass.cpp
index 49f242ddf596d37f527a533200afb7d7e2817cd1..10475403d22856fe11b96bbc78b4847e05c9700c 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.types/allocator_pointers.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.types/allocator_pointers.pass.cpp
@@ -109,7 +109,7 @@ void test_void_pointer()
 
 struct Foo { int x; };
 
-int main()
+int main(int, char**)
 {
     test_pointer<std::scoped_allocator_adaptor<std::allocator<char>>> ();
     test_pointer<std::scoped_allocator_adaptor<std::allocator<int>>> ();
@@ -118,7 +118,9 @@ int main()
     test_void_pointer<std::scoped_allocator_adaptor<std::allocator<char>>> ();
     test_void_pointer<std::scoped_allocator_adaptor<std::allocator<int>>> ();
     test_void_pointer<std::scoped_allocator_adaptor<std::allocator<Foo>>> ();
+
+  return 0;
 }
 #else
-int main() {}
+int main(int, char**) { return 0; }
 #endif
diff --git a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.types/inner_allocator_type.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.types/inner_allocator_type.pass.cpp
index 056189044284a8f80f08d9fb4fe7fbe76d1c4319..2aa7a98911477c212b623dc30d34383f7f7fefbc 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.types/inner_allocator_type.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.types/inner_allocator_type.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "allocators.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<
         std::scoped_allocator_adaptor<A1<int>>::inner_allocator_type,
@@ -33,4 +33,6 @@ int main()
     static_assert((std::is_same<
         std::scoped_allocator_adaptor<A1<int>, A2<int>, A3<int>>::inner_allocator_type,
         std::scoped_allocator_adaptor<A2<int>, A3<int>>>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.types/is_always_equal.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.types/is_always_equal.pass.cpp
index a549366c9d9b3d25cb2e416a33bf2cc916812912..628505f65cdc4f7afdc9f4617cd0511b32f1136f 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.types/is_always_equal.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.types/is_always_equal.pass.cpp
@@ -21,7 +21,7 @@
 #include "allocators.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     // sanity checks
     static_assert( (std::is_same<
@@ -68,4 +68,6 @@ int main()
               std::allocator_traits<A2<int>>::is_always_equal::value &&
               std::allocator_traits<A3<int>>::is_always_equal::value)
         ), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.types/propagate_on_container_copy_assignment.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.types/propagate_on_container_copy_assignment.pass.cpp
index 6f3605224bf82eaea72c6b947ba9f631f372b9af..fea53af299e7c8d521b8482dad8395ca13efddad 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.types/propagate_on_container_copy_assignment.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.types/propagate_on_container_copy_assignment.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "allocators.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<
         std::scoped_allocator_adaptor<A1<int>>::propagate_on_container_copy_assignment,
@@ -34,4 +34,6 @@ int main()
         std::scoped_allocator_adaptor<A1<int>, A2<int>, A3<int>>::propagate_on_container_copy_assignment,
         std::true_type>::value), "");
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.types/propagate_on_container_move_assignment.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.types/propagate_on_container_move_assignment.pass.cpp
index 5c207c930c4566faaa6403b9071d9d00f0ce42b5..d04ea6f1a43990e5eaa0cd8168ad6d812f057ccd 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.types/propagate_on_container_move_assignment.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.types/propagate_on_container_move_assignment.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "allocators.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<
         std::scoped_allocator_adaptor<A1<int>>::propagate_on_container_move_assignment,
@@ -34,4 +34,6 @@ int main()
         std::scoped_allocator_adaptor<A1<int>, A2<int>, A3<int>>::propagate_on_container_move_assignment,
         std::true_type>::value), "");
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.types/propagate_on_container_swap.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.types/propagate_on_container_swap.pass.cpp
index 5b70dd8fb924f8832a9276ef3a0410e39ebc5e88..fcec67879fcac44209aa36567ad74f9bb6f653a1 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.types/propagate_on_container_swap.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/allocator.adaptor.types/propagate_on_container_swap.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "allocators.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<
         std::scoped_allocator_adaptor<A1<int>>::propagate_on_container_swap,
@@ -33,4 +33,6 @@ int main()
     static_assert((std::is_same<
         std::scoped_allocator_adaptor<A1<int>, A2<int>, A3<int>>::propagate_on_container_swap,
         std::true_type>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/scoped.adaptor.operators/copy_assign.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/scoped.adaptor.operators/copy_assign.pass.cpp
index 0f3813e1ab9b2d4a9a3a6efd73704272e2d35e39..1f871876f1359065d3ab5d14dc80c37f1a0f63ee 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/scoped.adaptor.operators/copy_assign.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/scoped.adaptor.operators/copy_assign.pass.cpp
@@ -21,7 +21,7 @@
 
 #include "allocators.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::scoped_allocator_adaptor<A1<int>> A;
@@ -68,4 +68,6 @@ int main()
         assert(A3<int>::move_called == false);
         assert(aN == a1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/scoped.adaptor.operators/eq.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/scoped.adaptor.operators/eq.pass.cpp
index 22987adefe743bd1d90838a03861765b285fa714..aaf5c1d59add5f5709fde582c796d1c0c898248f 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/scoped.adaptor.operators/eq.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/scoped.adaptor.operators/eq.pass.cpp
@@ -28,7 +28,7 @@
 
 #include "allocators.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::scoped_allocator_adaptor<A1<int>> A;
@@ -58,4 +58,6 @@ int main()
         assert(a2 != a1);
         assert(!(a2 == a1));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/scoped.adaptor.operators/move_assign.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/scoped.adaptor.operators/move_assign.pass.cpp
index 0342f614c989e6d36066e50eb165b1d803377fc1..c17c6d38439970f9a2292d1cd02330d52b000d06 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/scoped.adaptor.operators/move_assign.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/scoped.adaptor.operators/move_assign.pass.cpp
@@ -21,7 +21,7 @@
 
 #include "allocators.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::scoped_allocator_adaptor<A1<int>> A;
@@ -68,4 +68,6 @@ int main()
         assert(A3<int>::move_called == true);
         assert(aN == a1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/allocator.adaptor/types.pass.cpp b/libcxx/test/std/utilities/allocator.adaptor/types.pass.cpp
index 00a007f06ea20c0fa0c5184d21caefa01e972956..7820e29eef27fc7391d6fb2921a8b6c41494e0e7 100644
--- a/libcxx/test/std/utilities/allocator.adaptor/types.pass.cpp
+++ b/libcxx/test/std/utilities/allocator.adaptor/types.pass.cpp
@@ -29,7 +29,7 @@
 
 #include "allocators.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<
         A1<int>,
@@ -96,4 +96,6 @@ int main()
     static_assert((std::is_same<
         std::scoped_allocator_adaptor<A2<int>, A1<int>>::const_void_pointer,
         const void*>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/any/any.class/any.assign/copy.pass.cpp b/libcxx/test/std/utilities/any/any.class/any.assign/copy.pass.cpp
index 0a8c3f7814bc622cfe97becd02324654c76cd594..6cf1efb86b304e4e24e93e272b48804220f7b690 100644
--- a/libcxx/test/std/utilities/any/any.class/any.assign/copy.pass.cpp
+++ b/libcxx/test/std/utilities/any/any.class/any.assign/copy.pass.cpp
@@ -191,7 +191,7 @@ void test_copy_assign_throws()
 #endif
 }
 
-int main() {
+int main(int, char**) {
     test_copy_assign<small1, small2>();
     test_copy_assign<large1, large2>();
     test_copy_assign<small, large>();
@@ -201,4 +201,6 @@ int main() {
     test_copy_assign_self();
     test_copy_assign_throws<small_throws_on_copy>();
     test_copy_assign_throws<large_throws_on_copy>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/any/any.class/any.assign/move.pass.cpp b/libcxx/test/std/utilities/any/any.class/any.assign/move.pass.cpp
index 4baadb2bbad280d39699b5fcdbe78c8d4537d740..6e1b6d6a6f4361796f2300c401f81751c6c46857 100644
--- a/libcxx/test/std/utilities/any/any.class/any.assign/move.pass.cpp
+++ b/libcxx/test/std/utilities/any/any.class/any.assign/move.pass.cpp
@@ -104,7 +104,7 @@ void test_move_assign_noexcept() {
       );
 }
 
-int main() {
+int main(int, char**) {
     test_move_assign_noexcept();
     test_move_assign<small1, small2>();
     test_move_assign<large1, large2>();
@@ -112,4 +112,6 @@ int main() {
     test_move_assign<large, small>();
     test_move_assign_empty<small>();
     test_move_assign_empty<large>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/any/any.class/any.assign/value.pass.cpp b/libcxx/test/std/utilities/any/any.class/any.assign/value.pass.cpp
index 7ccec4b3f88d039ed254eba339fe75281870bd64..888a6a654b370905da105c15a59be0fda01551c8 100644
--- a/libcxx/test/std/utilities/any/any.class/any.assign/value.pass.cpp
+++ b/libcxx/test/std/utilities/any/any.class/any.assign/value.pass.cpp
@@ -202,7 +202,7 @@ void test_sfinae_constraints() {
     }
 }
 
-int main() {
+int main(int, char**) {
     test_assign_value<small1, small2>();
     test_assign_value<large1, large2>();
     test_assign_value<small, large>();
@@ -213,4 +213,6 @@ int main() {
     test_assign_throws<large_throws_on_copy>();
     test_assign_throws<throws_on_move, /* Move = */ true>();
     test_sfinae_constraints();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/any/any.class/any.cons/copy.pass.cpp b/libcxx/test/std/utilities/any/any.class/any.cons/copy.pass.cpp
index 6c4e9576d44014d6c17a33ed47087b3a1ad5ce56..318d9ecabba202e6afa1fc12a1ca2021c2e6e1b7 100644
--- a/libcxx/test/std/utilities/any/any.class/any.cons/copy.pass.cpp
+++ b/libcxx/test/std/utilities/any/any.class/any.cons/copy.pass.cpp
@@ -98,10 +98,12 @@ void test_copy()
     assert(Type::count == 0);
 }
 
-int main() {
+int main(int, char**) {
     test_copy<small>();
     test_copy<large>();
     test_copy_empty();
     test_copy_throws<small_throws_on_copy>();
     test_copy_throws<large_throws_on_copy>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/any/any.class/any.cons/default.pass.cpp b/libcxx/test/std/utilities/any/any.class/any.cons/default.pass.cpp
index 12692a1711306c9bc5c1cfe028d38710f4c659d4..6cd7b8937d20b32bd13f18023f2b49607a3cda7e 100644
--- a/libcxx/test/std/utilities/any/any.class/any.cons/default.pass.cpp
+++ b/libcxx/test/std/utilities/any/any.class/any.cons/default.pass.cpp
@@ -20,7 +20,7 @@
 #include "any_helpers.h"
 #include "count_new.hpp"
 
-int main()
+int main(int, char**)
 {
     using std::any;
     {
@@ -43,4 +43,6 @@ int main()
         any const a;
         assertEmpty(a);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/any/any.class/any.cons/in_place_type.pass.cpp b/libcxx/test/std/utilities/any/any.class/any.cons/in_place_type.pass.cpp
index f696ac5a206f54fe15250216ab0914104119acf4..9684fcac7e2d5ec96a8064453d269f7d7571dbb1 100644
--- a/libcxx/test/std/utilities/any/any.class/any.cons/in_place_type.pass.cpp
+++ b/libcxx/test/std/utilities/any/any.class/any.cons/in_place_type.pass.cpp
@@ -187,7 +187,7 @@ void test_constructor_explicit() {
     static_assert(std::is_constructible<std::any, IT, std::initializer_list<int>&, int>::value, "");
 }
 
-int main() {
+int main(int, char**) {
     test_in_place_type<small>();
     test_in_place_type<large>();
     test_in_place_type<small_throws_on_copy>();
@@ -198,4 +198,6 @@ int main() {
     test_in_place_type_decayed();
     test_ctor_sfinae();
     test_constructor_explicit();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/any/any.class/any.cons/move.pass.cpp b/libcxx/test/std/utilities/any/any.class/any.cons/move.pass.cpp
index 265972a01e9b1429360a9628f7a34b66c9538793..e75d56ef290ce74b85a9ec756ceed41821d32120 100644
--- a/libcxx/test/std/utilities/any/any.class/any.cons/move.pass.cpp
+++ b/libcxx/test/std/utilities/any/any.class/any.cons/move.pass.cpp
@@ -95,7 +95,7 @@ void test_move() {
     assert(Type::count == 0);
 }
 
-int main()
+int main(int, char**)
 {
     // noexcept test
     {
@@ -108,4 +108,6 @@ int main()
     test_move<large>();
     test_move_empty();
     test_move_does_not_throw();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/any/any.class/any.cons/value.pass.cpp b/libcxx/test/std/utilities/any/any.class/any.cons/value.pass.cpp
index c80a407ff063598e0d52d2f71055c579b64befe9..ed588497514c4fe17c2a1eaa7f59f66e9315fb65 100644
--- a/libcxx/test/std/utilities/any/any.class/any.cons/value.pass.cpp
+++ b/libcxx/test/std/utilities/any/any.class/any.cons/value.pass.cpp
@@ -151,11 +151,13 @@ void test_sfinae_constraints() {
     }
 }
 
-int main() {
+int main(int, char**) {
     test_copy_move_value<small>();
     test_copy_move_value<large>();
     test_copy_value_throws<small_throws_on_copy>();
     test_copy_value_throws<large_throws_on_copy>();
     test_move_value_throws();
     test_sfinae_constraints();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/any/any.class/any.modifiers/emplace.pass.cpp b/libcxx/test/std/utilities/any/any.class/any.modifiers/emplace.pass.cpp
index 3ac003dd086ce060ba63eb885c90a5b3cff110cb..7cb5d4913282a71f2a34f3f8fcde41c5c2e220aa 100644
--- a/libcxx/test/std/utilities/any/any.class/any.modifiers/emplace.pass.cpp
+++ b/libcxx/test/std/utilities/any/any.class/any.modifiers/emplace.pass.cpp
@@ -275,7 +275,7 @@ void test_emplace_sfinae_constraints() {
     }
 }
 
-int main() {
+int main(int, char**) {
     test_emplace_type<small>();
     test_emplace_type<large>();
     test_emplace_type<small_throws_on_copy>();
@@ -288,4 +288,6 @@ int main() {
     test_emplace_throws<SmallThrows>();
     test_emplace_throws<LargeThrows>();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/any/any.class/any.modifiers/reset.pass.cpp b/libcxx/test/std/utilities/any/any.class/any.modifiers/reset.pass.cpp
index 352b25b8010af67c70e0238bc9cb6d17f5a70850..0a01e86252ceba840992c21baeb3f87c308a1a71 100644
--- a/libcxx/test/std/utilities/any/any.class/any.modifiers/reset.pass.cpp
+++ b/libcxx/test/std/utilities/any/any.class/any.modifiers/reset.pass.cpp
@@ -25,7 +25,7 @@
 
 #include "any_helpers.h"
 
-int main()
+int main(int, char**)
 {
     using std::any;
     using std::any_cast;
@@ -67,4 +67,6 @@ int main()
         assertEmpty<large>(a);
         assert(large::count == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/any/any.class/any.modifiers/swap.pass.cpp b/libcxx/test/std/utilities/any/any.class/any.modifiers/swap.pass.cpp
index f1ff60d478ba8ab166d6eefb9824c56b97dc3088..f4f5ee4969c7540fe960283b651f2ac04a82ff9c 100644
--- a/libcxx/test/std/utilities/any/any.class/any.modifiers/swap.pass.cpp
+++ b/libcxx/test/std/utilities/any/any.class/any.modifiers/swap.pass.cpp
@@ -127,7 +127,7 @@ void test_self_swap() {
     assert(large::count == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test_noexcept();
     test_swap_empty<small>();
@@ -137,4 +137,6 @@ int main()
     test_swap<small, large>();
     test_swap<large, small>();
     test_self_swap();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/any/any.class/any.observers/has_value.pass.cpp b/libcxx/test/std/utilities/any/any.class/any.observers/has_value.pass.cpp
index 9b747dca6102b8313f3aa25bf9ae2e8b809c5316..54b4153c9749e89213d21174b76dd76a38c3d3d1 100644
--- a/libcxx/test/std/utilities/any/any.class/any.observers/has_value.pass.cpp
+++ b/libcxx/test/std/utilities/any/any.class/any.observers/has_value.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "any_helpers.h"
 
-int main()
+int main(int, char**)
 {
     using std::any;
     // noexcept test
@@ -60,4 +60,6 @@ int main()
         a = l;
         assert(a.has_value());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/any/any.class/any.observers/type.pass.cpp b/libcxx/test/std/utilities/any/any.class/any.observers/type.pass.cpp
index 8d3b4081405c0be93dd568aa17fb94c7f9440f7f..bb9089cd83e309da967864c77b75d3d53673965d 100644
--- a/libcxx/test/std/utilities/any/any.class/any.observers/type.pass.cpp
+++ b/libcxx/test/std/utilities/any/any.class/any.observers/type.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include "any_helpers.h"
 
-int main()
+int main(int, char**)
 {
     using std::any;
     {
@@ -37,4 +37,6 @@ int main()
         any const a(l);
         assert(a.type() == typeid(large));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/any/any.class/not_literal_type.pass.cpp b/libcxx/test/std/utilities/any/any.class/not_literal_type.pass.cpp
index b757f7b0bbe1351496325f8e7dd80b9b52500666..3a275d51e4ac73f92e578762434571c35db264c1 100644
--- a/libcxx/test/std/utilities/any/any.class/not_literal_type.pass.cpp
+++ b/libcxx/test/std/utilities/any/any.class/not_literal_type.pass.cpp
@@ -15,6 +15,8 @@
 #include <any>
 #include <type_traits>
 
-int main () {
+int main(int, char**) {
     static_assert(!std::is_literal_type<std::any>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/any/any.nonmembers/any.cast/any_cast_pointer.pass.cpp b/libcxx/test/std/utilities/any/any.nonmembers/any.cast/any_cast_pointer.pass.cpp
index 8de9164c31ff467f8d8d36d8134ba7bf2404336d..9b9ec4109585e234c44762ab812beeea0249b983 100644
--- a/libcxx/test/std/utilities/any/any.nonmembers/any.cast/any_cast_pointer.pass.cpp
+++ b/libcxx/test/std/utilities/any/any.nonmembers/any.cast/any_cast_pointer.pass.cpp
@@ -166,7 +166,7 @@ void test_cast_function_pointer() {
     assert(fn_ptr == test_fn);
 }
 
-int main() {
+int main(int, char**) {
     test_cast_is_noexcept();
     test_cast_return_type();
     test_cast_nullptr();
@@ -175,4 +175,6 @@ int main() {
     test_cast<large>();
     test_cast_non_copyable_type();
     test_cast_function_pointer();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/any/any.nonmembers/any.cast/any_cast_reference.pass.cpp b/libcxx/test/std/utilities/any/any.nonmembers/any.cast/any_cast_reference.pass.cpp
index 810c482df78218f13d3bd2332221070ddd7907f4..fb69f0d39fb713a4d1e9ac2d3892d70466267ab3 100644
--- a/libcxx/test/std/utilities/any/any.nonmembers/any.cast/any_cast_reference.pass.cpp
+++ b/libcxx/test/std/utilities/any/any.nonmembers/any.cast/any_cast_reference.pass.cpp
@@ -309,7 +309,7 @@ void test_cast_to_value() {
     assert(Type::count == 0);
 }
 
-int main() {
+int main(int, char**) {
     test_cast_is_not_noexcept();
     test_cast_return_type();
     test_cast_empty();
@@ -317,4 +317,6 @@ int main() {
     test_cast_to_reference<large>();
     test_cast_to_value<small>();
     test_cast_to_value<large>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/any/any.nonmembers/any.cast/any_cast_request_invalid_value_category.fail.cpp b/libcxx/test/std/utilities/any/any.nonmembers/any.cast/any_cast_request_invalid_value_category.fail.cpp
index cd69a3d8508afb582c012d2d3bcedfea015d5076..396d994d22dd2ac28fbed2a21482bf2d916a3e1c 100644
--- a/libcxx/test/std/utilities/any/any.nonmembers/any.cast/any_cast_request_invalid_value_category.fail.cpp
+++ b/libcxx/test/std/utilities/any/any.nonmembers/any.cast/any_cast_request_invalid_value_category.fail.cpp
@@ -61,9 +61,11 @@ void test_rvalue_any_cast_request_lvalue()
     any_cast<int&>(42);
 }
 
-int main()
+int main(int, char**)
 {
     test_const_lvalue_cast_request_non_const_lvalue();
     test_lvalue_any_cast_request_rvalue();
     test_rvalue_any_cast_request_lvalue();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/any/any.nonmembers/any.cast/const_correctness.fail.cpp b/libcxx/test/std/utilities/any/any.nonmembers/any.cast/const_correctness.fail.cpp
index c0c6e03fdcf329123b4be8dcf54e483c66ab969c..8669de4fddb19f6843751414251129ef1b9c3471 100644
--- a/libcxx/test/std/utilities/any/any.nonmembers/any.cast/const_correctness.fail.cpp
+++ b/libcxx/test/std/utilities/any/any.nonmembers/any.cast/const_correctness.fail.cpp
@@ -24,7 +24,7 @@ struct TestType2 {};
 // is triggered by these tests.
 // expected-error@const_correctness.fail.cpp:* 0+ {{call to unavailable function 'any_cast': introduced in macOS 10.14}}
 
-int main()
+int main(int, char**)
 {
     using std::any;
     using std::any_cast;
@@ -46,4 +46,6 @@ int main()
     // expected-error@any:* {{cannot cast from lvalue of type 'const TestType2' to rvalue reference type 'TestType2 &&'; types are not compatible}}
     // expected-error-re@any:* {{static_assert failed{{.*}} "ValueType is required to be a const lvalue reference or a CopyConstructible type"}}
     any_cast<TestType2 &&>(static_cast<any const&&>(a)); // expected-note {{requested here}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/any/any.nonmembers/any.cast/not_copy_constructible.fail.cpp b/libcxx/test/std/utilities/any/any.nonmembers/any.cast/not_copy_constructible.fail.cpp
index c90df2ebd3739ad3f55187c6312523e9b6967180..97f1d9795bc0e26f705082df4f855fb12a1316e4 100644
--- a/libcxx/test/std/utilities/any/any.nonmembers/any.cast/not_copy_constructible.fail.cpp
+++ b/libcxx/test/std/utilities/any/any.nonmembers/any.cast/not_copy_constructible.fail.cpp
@@ -43,7 +43,7 @@ struct no_move {
 // is triggered by these tests.
 // expected-error@not_copy_constructible.fail.cpp:* 0+ {{call to unavailable function 'any_cast': introduced in macOS 10.14}}
 
-int main() {
+int main(int, char**) {
     any a;
     // expected-error-re@any:* {{static_assert failed{{.*}} "ValueType is required to be an lvalue reference or a CopyConstructible type"}}
     // expected-error@any:* {{static_cast from 'no_copy' to 'no_copy' uses deleted function}}
@@ -58,4 +58,6 @@ int main() {
     // expected-error-re@any:* {{static_assert failed{{.*}} "ValueType is required to be an rvalue reference or a CopyConstructible type"}}
     // expected-error@any:* {{static_cast from 'typename remove_reference<no_move &>::type' (aka 'no_move') to 'no_move' uses deleted function}}
     any_cast<no_move>(static_cast<any &&>(a));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/any/any.nonmembers/any.cast/reference_types.fail.cpp b/libcxx/test/std/utilities/any/any.nonmembers/any.cast/reference_types.fail.cpp
index 19453582479cb2a52fdc73f38bf6376bbb4e60a4..1ce06e289a900bd28b258a0d61c9e535582273a2 100644
--- a/libcxx/test/std/utilities/any/any.nonmembers/any.cast/reference_types.fail.cpp
+++ b/libcxx/test/std/utilities/any/any.nonmembers/any.cast/reference_types.fail.cpp
@@ -21,7 +21,7 @@
 using std::any;
 using std::any_cast;
 
-int main()
+int main(int, char**)
 {
     any a(1);
 
@@ -50,4 +50,6 @@ int main()
 
     // expected-error-re@any:* 1 {{static_assert failed{{.*}} "_ValueType may not be a reference."}}
     any_cast<int const &&>(&a2); // expected-note {{requested here}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/any/any.nonmembers/make_any.pass.cpp b/libcxx/test/std/utilities/any/any.nonmembers/make_any.pass.cpp
index e185f239f6981f2ac4897bdb5097997893415d26..1e9708545ff079ee5b24151be306e392263119dc 100644
--- a/libcxx/test/std/utilities/any/any.nonmembers/make_any.pass.cpp
+++ b/libcxx/test/std/utilities/any/any.nonmembers/make_any.pass.cpp
@@ -131,7 +131,7 @@ void test_make_any_throws()
 
 #endif
 
-int main() {
+int main(int, char**) {
     test_make_any_type<small>();
     test_make_any_type<large>();
     test_make_any_type<small_throws_on_copy>();
@@ -144,4 +144,6 @@ int main() {
     test_make_any_throws<LargeThrows>();
 
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/any/any.nonmembers/swap.pass.cpp b/libcxx/test/std/utilities/any/any.nonmembers/swap.pass.cpp
index 3e5a91d0d2360051f60ba926ee0f3bc573f0b63a..cff34964a84eb42cdfe7f2594aa6d8d5c2c1b4a8 100644
--- a/libcxx/test/std/utilities/any/any.nonmembers/swap.pass.cpp
+++ b/libcxx/test/std/utilities/any/any.nonmembers/swap.pass.cpp
@@ -28,7 +28,7 @@
 using std::any;
 using std::any_cast;
 
-int main()
+int main(int, char**)
 {
 
     { // test noexcept
@@ -44,4 +44,6 @@ int main()
         assert(any_cast<int>(a1) == 2);
         assert(any_cast<int>(a2) == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/charconv/charconv.from.chars/integral.bool.fail.cpp b/libcxx/test/std/utilities/charconv/charconv.from.chars/integral.bool.fail.cpp
index 35ddfa32e887c48e9fa3143e3816b5e82ac89f37..2e744cc81875fba5de6d9bc1038c69f5fe7dcca1 100644
--- a/libcxx/test/std/utilities/charconv/charconv.from.chars/integral.bool.fail.cpp
+++ b/libcxx/test/std/utilities/charconv/charconv.from.chars/integral.bool.fail.cpp
@@ -18,7 +18,7 @@
 
 #include <charconv>
 
-int main()
+int main(int, char**)
 {
     using std::from_chars;
     char buf[] = "01001";
@@ -26,4 +26,6 @@ int main()
 
     from_chars(buf, buf + sizeof(buf), lv);      // expected-error {{call to deleted function}}
     from_chars(buf, buf + sizeof(buf), lv, 16);  // expected-error {{call to deleted function}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/charconv/charconv.from.chars/integral.pass.cpp b/libcxx/test/std/utilities/charconv/charconv.from.chars/integral.pass.cpp
index 9f05250d356eba2c1c773babf887c94218875943..d750cb4a89c4d5a79fe3e3c0b2db26b84a01b8f2 100644
--- a/libcxx/test/std/utilities/charconv/charconv.from.chars/integral.pass.cpp
+++ b/libcxx/test/std/utilities/charconv/charconv.from.chars/integral.pass.cpp
@@ -183,8 +183,10 @@ struct test_signed : roundtrip_test_base<T>
     }
 };
 
-int main()
+int main(int, char**)
 {
     run<test_basics>(integrals);
     run<test_signed>(all_signed);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/charconv/charconv.to.chars/integral.bool.fail.cpp b/libcxx/test/std/utilities/charconv/charconv.to.chars/integral.bool.fail.cpp
index 36c7d3ccadb56c26849c5cdc24dc92cdeee21ffd..5c947d122f49fc90fbbc6dca8eb6018c7677ec2d 100644
--- a/libcxx/test/std/utilities/charconv/charconv.to.chars/integral.bool.fail.cpp
+++ b/libcxx/test/std/utilities/charconv/charconv.to.chars/integral.bool.fail.cpp
@@ -18,7 +18,7 @@
 
 #include <charconv>
 
-int main()
+int main(int, char**)
 {
     using std::to_chars;
     char buf[10];
@@ -26,4 +26,6 @@ int main()
 
     to_chars(buf, buf + sizeof(buf), false);   // expected-error {{call to deleted function}}
     to_chars(buf, buf + sizeof(buf), lv, 16);  // expected-error {{call to deleted function}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/charconv/charconv.to.chars/integral.pass.cpp b/libcxx/test/std/utilities/charconv/charconv.to.chars/integral.pass.cpp
index 18ddf203b3e046988e827aa74da80b0773f082ad..c034151de8a8acb324f0689279f431b617c67488 100644
--- a/libcxx/test/std/utilities/charconv/charconv.to.chars/integral.pass.cpp
+++ b/libcxx/test/std/utilities/charconv/charconv.to.chars/integral.pass.cpp
@@ -81,8 +81,10 @@ struct test_signed : to_chars_test_base<T>
     }
 };
 
-int main()
+int main(int, char**)
 {
     run<test_basics>(integrals);
     run<test_signed>(all_signed);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/arithmetic.operations/divides.pass.cpp b/libcxx/test/std/utilities/function.objects/arithmetic.operations/divides.pass.cpp
index c191b191bcdcce3ae3d8073188608352d7712436..1dbbd8533c7d26b254be4292393a42d2a0cecd11 100644
--- a/libcxx/test/std/utilities/function.objects/arithmetic.operations/divides.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/arithmetic.operations/divides.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::divides<int> F;
     const F f = F();
@@ -37,4 +37,6 @@ int main()
     constexpr double bar = std::divides<> () (3.0, 2);
     static_assert ( bar == 1.5, "" ); // exact in binary
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/arithmetic.operations/minus.pass.cpp b/libcxx/test/std/utilities/function.objects/arithmetic.operations/minus.pass.cpp
index 54ab577ea432cf191da7b0e1f2dcecee5ca232d3..186695f7b93eb9ec2f629c0699719fc9a987466d 100644
--- a/libcxx/test/std/utilities/function.objects/arithmetic.operations/minus.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/arithmetic.operations/minus.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::minus<int> F;
     const F f = F();
@@ -37,4 +37,6 @@ int main()
     constexpr double bar = std::minus<> () (3.0, 2);
     static_assert ( bar == 1.0, "" );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/arithmetic.operations/modulus.pass.cpp b/libcxx/test/std/utilities/function.objects/arithmetic.operations/modulus.pass.cpp
index f426c57cfee605a455088f8b533c2a237d1e9568..3679a2d32513a3acdc10fdad2c50eccdfd341104 100644
--- a/libcxx/test/std/utilities/function.objects/arithmetic.operations/modulus.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/arithmetic.operations/modulus.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::modulus<int> F;
     const F f = F();
@@ -37,4 +37,6 @@ int main()
     constexpr int bar = std::modulus<> () (3L, 2);
     static_assert ( bar == 1, "" );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/arithmetic.operations/multiplies.pass.cpp b/libcxx/test/std/utilities/function.objects/arithmetic.operations/multiplies.pass.cpp
index 5ef4791b59ea6e2c684cb1ff43174d0a31f37837..a09e59c784c793219fbe2edcf2c358c3ef4b8231 100644
--- a/libcxx/test/std/utilities/function.objects/arithmetic.operations/multiplies.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/arithmetic.operations/multiplies.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::multiplies<int> F;
     const F f = F();
@@ -37,4 +37,6 @@ int main()
     constexpr double bar = std::multiplies<> () (3.0, 2);
     static_assert ( bar == 6.0, "" );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/arithmetic.operations/negate.pass.cpp b/libcxx/test/std/utilities/function.objects/arithmetic.operations/negate.pass.cpp
index d7346c769f7219d26b90c1959ba1b452a397134f..553bf83e2d4c24b73d51e67e61381b6e5f29871e 100644
--- a/libcxx/test/std/utilities/function.objects/arithmetic.operations/negate.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/arithmetic.operations/negate.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::negate<int> F;
     const F f = F();
@@ -36,4 +36,6 @@ int main()
     constexpr double bar = std::negate<> () (3.0);
     static_assert ( bar == -3.0, "" );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/arithmetic.operations/plus.pass.cpp b/libcxx/test/std/utilities/function.objects/arithmetic.operations/plus.pass.cpp
index 6bca266e0781667e264ebcd953557e7c650c5456..b2614f4304d2099472325c51cc9f97e7c8f0e492 100644
--- a/libcxx/test/std/utilities/function.objects/arithmetic.operations/plus.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/arithmetic.operations/plus.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::plus<int> F;
     const F f = F();
@@ -37,4 +37,6 @@ int main()
     constexpr double bar = std::plus<> () (3.0, 2);
     static_assert ( bar == 5.0, "" );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/arithmetic.operations/transparent.pass.cpp b/libcxx/test/std/utilities/function.objects/arithmetic.operations/transparent.pass.cpp
index ca57c223a2aa6813b5a8572534d01aa3b1368a38..154a0f8877a5fe8d12b8c0c0d6791b106f175364 100644
--- a/libcxx/test/std/utilities/function.objects/arithmetic.operations/transparent.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/arithmetic.operations/transparent.pass.cpp
@@ -22,7 +22,7 @@ public:
 };
 
 
-int main ()
+int main(int, char**)
 {
     static_assert ( !is_transparent<std::plus<int>>::value, "" );
     static_assert ( !is_transparent<std::plus<std::string>>::value, "" );
diff --git a/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/PR23141_invoke_not_constexpr.pass.cpp b/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/PR23141_invoke_not_constexpr.pass.cpp
index 4c025d1415afe4855440a51c3ceeb5dccff98abc..931778f54d91c40f8ae26857045bd95d961ab7ca 100644
--- a/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/PR23141_invoke_not_constexpr.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/PR23141_invoke_not_constexpr.pass.cpp
@@ -28,7 +28,9 @@ struct Fun
   }
 };
 
-int main()
+int main(int, char**)
 {
     std::bind(Fun{}, std::placeholders::_1, 42)("hello");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/bind_return_type.pass.cpp b/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/bind_return_type.pass.cpp
index fc089e16528d46a249da645a0cc534d0e0b96757..7010b33f3314e19a7db29e00c50fcbc64b67b41c 100644
--- a/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/bind_return_type.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/bind_return_type.pass.cpp
@@ -115,7 +115,7 @@ void do_test_r(Fn* func) {
     }
 }
 
-int main()
+int main(int, char**)
 {
     do_test<int>(return_value);
     do_test<int&>(return_lvalue);
@@ -129,4 +129,6 @@ int main()
     do_test_r<long>(return_rvalue);
     do_test_r<long>(return_const_rvalue);
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/copy.pass.cpp b/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/copy.pass.cpp
index ccc6c27e716f40e52475210811252a5293310009..8beeb3321d517ac79645dcdec5a7eaeae878039f 100644
--- a/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/copy.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/copy.pass.cpp
@@ -26,11 +26,13 @@ float _pow(float a, float b)
     return std::pow(a, b);
 }
 
-int main()
+int main(int, char**)
 {
     std::function<float(float, float)> fnc = _pow;
     auto task = std::bind(fnc, 2.f, 4.f);
     auto task2(task);
     assert(task() == 16);
     assert(task2() == 16);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/invoke_function_object.pass.cpp b/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/invoke_function_object.pass.cpp
index b386b99a90fb463c445ada1c4bdec266ee23392a..b87918da110474de186c47edf2f4285546a049c1 100644
--- a/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/invoke_function_object.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/invoke_function_object.pass.cpp
@@ -38,7 +38,7 @@ struct BadUnaryFunction
     }
 };
 
-int main()
+int main(int, char**)
 {
     // Check that BadUnaryFunction::operator()(S const &) is not
     // instantiated when checking if BadUnaryFunction is a nested bind
@@ -47,4 +47,6 @@ int main()
     b(0);
     auto b2 = std::bind<long>(DummyUnaryFunction(), BadUnaryFunction());
     b2(0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/invoke_int_0.pass.cpp b/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/invoke_int_0.pass.cpp
index 8d6bc70e79a8030f4b3b73d1c3ed02170e4d76f5..a77e1895d6f748ee2b61c9af50473742517d3ded 100644
--- a/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/invoke_int_0.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/invoke_int_0.pass.cpp
@@ -40,7 +40,7 @@ struct A_int_0
     int operator()() const {return 5;}
 };
 
-int main()
+int main(int, char**)
 {
     test(std::bind(f), 1);
     test(std::bind(&f), 1);
@@ -51,4 +51,6 @@ int main()
     test(std::bind<int>(&f), 1);
     test(std::bind<int>(A_int_0()), 4);
     test_const(std::bind<int>(A_int_0()), 5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/invoke_lvalue.pass.cpp b/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/invoke_lvalue.pass.cpp
index 92f65af2c91bf779b0697194b91e406dea40427a..9b81d3301325cc5f404985952d1e269a7ff62bad 100644
--- a/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/invoke_lvalue.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/invoke_lvalue.pass.cpp
@@ -280,10 +280,12 @@ test3()
     assert(b);
 }
 
-int main()
+int main(int, char**)
 {
     test_void_1();
     test_int_1();
     test_void_2();
     test3();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/invoke_rvalue.pass.cpp b/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/invoke_rvalue.pass.cpp
index b7facb38ac6ec64a713378db544a04be959ae199..10d2ce017f8fa59dc4b77ab900f21664d7a239e9 100644
--- a/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/invoke_rvalue.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/invoke_rvalue.pass.cpp
@@ -258,10 +258,12 @@ void test_nested()
     assert(std::bind(f_nested, std::bind(g_nested, _1))(3) == 31);
 }
 
-int main()
+int main(int, char**)
 {
     test_void_1();
     test_int_1();
     test_void_2();
     test_nested();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/invoke_void_0.pass.cpp b/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/invoke_void_0.pass.cpp
index cc982d1b80f9a5a5d215b0dc2018c8dc37665c56..2c8e56f034e8cb7f63839c7471b019fe5d125923 100644
--- a/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/invoke_void_0.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/invoke_void_0.pass.cpp
@@ -54,7 +54,7 @@ struct A_int_0
     int operator()() const {count += 2; return 5;}
 };
 
-int main()
+int main(int, char**)
 {
     test(std::bind(f));
     test(std::bind(&f));
@@ -70,4 +70,6 @@ int main()
     test(std::bind<void>(&g));
     test(std::bind<void>(A_int_0()));
     test_const(std::bind<void>(A_int_0()));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/nested.pass.cpp b/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/nested.pass.cpp
index c4d82948e374bb4912782e375560cc7d70476191..0d5be34135393b632f08e019f177524ef0af1f0a 100644
--- a/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/nested.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.bind/nested.pass.cpp
@@ -41,11 +41,13 @@ struct plus_one
   }
 };
 
-int main()
+int main(int, char**)
 {
     using std::placeholders::_1;
 
     auto g = std::bind(power(), 2, _1);
     assert(g(5) == 32);
     assert(std::bind(plus_one(), g)(5) == 33);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.isbind/is_bind_expression.pass.cpp b/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.isbind/is_bind_expression.pass.cpp
index cf065e4e3823d639639cd0bb99c6e72a7f4df138..8314dbe1e8e2a87cccb110c83996f7d16ea946bd 100644
--- a/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.isbind/is_bind_expression.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.isbind/is_bind_expression.pass.cpp
@@ -27,11 +27,13 @@ test(const T&)
 
 struct C {};
 
-int main()
+int main(int, char**)
 {
     test<true>(std::bind(C()));
     test<true>(std::bind(C(), std::placeholders::_2));
     test<true>(std::bind<int>(C()));
     test<false>(1);
     test<false>(std::placeholders::_2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.isbind/is_bind_expression_03.pass.cpp b/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.isbind/is_bind_expression_03.pass.cpp
index da7880fb25fe7081603812c77758adb78576308a..c1af159b29366b18c80553693a600ad6b29457df 100644
--- a/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.isbind/is_bind_expression_03.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.isbind/is_bind_expression_03.pass.cpp
@@ -24,7 +24,7 @@ void test() {
 
 struct C {};
 
-int main() {
+int main(int, char**) {
     test<int>();
     test<void>();
     test<C>();
@@ -35,4 +35,6 @@ int main() {
     test<int(*)()>();
     test<int (C::*)()>();
     test<decltype(std::placeholders::_2)>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.isbind/is_placeholder.pass.cpp b/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.isbind/is_placeholder.pass.cpp
index ecaa45bba28dd2b4e7c37641fe3bb66b0d1703d5..d2ccf1fafdccf8b8a21eea63943d0ace56fd39c6 100644
--- a/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.isbind/is_placeholder.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.isbind/is_placeholder.pass.cpp
@@ -25,7 +25,7 @@ test(const T&)
 
 struct C {};
 
-int main()
+int main(int, char**)
 {
     test<1>(std::placeholders::_1);
     test<2>(std::placeholders::_2);
@@ -41,4 +41,6 @@ int main()
     test<0>(5.5);
     test<0>('a');
     test<0>(C());
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.place/placeholders.pass.cpp b/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.place/placeholders.pass.cpp
index 8e4ec60ef13d6b675dd070047ffbf630fbb82685..b71aae818a062e9b62d1b6d11bfc1ec1b83863cf 100644
--- a/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.place/placeholders.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/bind/func.bind/func.bind.place/placeholders.pass.cpp
@@ -80,7 +80,7 @@ void use_placeholders_to_prevent_unused_warning() {
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     use_placeholders_to_prevent_unused_warning();
     test(std::placeholders::_1);
@@ -93,4 +93,6 @@ int main()
     test(std::placeholders::_8);
     test(std::placeholders::_9);
     test(std::placeholders::_10);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/bind/func.bind/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/function.objects/bind/func.bind/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/function.objects/bind/func.bind/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/bind/func.bind/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/bind/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/function.objects/bind/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/function.objects/bind/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/bind/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/bitwise.operations/bit_and.pass.cpp b/libcxx/test/std/utilities/function.objects/bitwise.operations/bit_and.pass.cpp
index 664e3f25dd6bbd2a0c020c5b3a5dda22b75d820d..aa5324621454ad09b94c0b97dcb1cf162647a910 100644
--- a/libcxx/test/std/utilities/function.objects/bitwise.operations/bit_and.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/bitwise.operations/bit_and.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::bit_and<int> F;
     const F f = F();
@@ -57,4 +57,6 @@ int main()
     constexpr int bar = std::bit_and<> () (0x58D3L, 0xEA95);
     static_assert ( bar == 0x4891, "" );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/bitwise.operations/bit_not.pass.cpp b/libcxx/test/std/utilities/function.objects/bitwise.operations/bit_not.pass.cpp
index e18139bc607dd2899d60b93da0ebb7c3ccc9c2dd..8bfa48f3e70ca1ea4f8843c62e526560be1bdc4d 100644
--- a/libcxx/test/std/utilities/function.objects/bitwise.operations/bit_not.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/bitwise.operations/bit_not.pass.cpp
@@ -15,7 +15,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::bit_not<int> F;
     const F f = F();
@@ -42,4 +42,6 @@ int main()
 
     constexpr int bar = std::bit_not<> () (0xEA95) & 0xFFFF;
     static_assert ( bar == 0x156A, "" );
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/bitwise.operations/bit_or.pass.cpp b/libcxx/test/std/utilities/function.objects/bitwise.operations/bit_or.pass.cpp
index 19bd1a731c805f965fa669b35971768d68ca6327..8abcd63afaa7bb7a6dfe46d7084ff4ecf55fd4a3 100644
--- a/libcxx/test/std/utilities/function.objects/bitwise.operations/bit_or.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/bitwise.operations/bit_or.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::bit_or<int> F;
     const F f = F();
@@ -57,4 +57,6 @@ int main()
     constexpr int bar = std::bit_or<> () (0x58D3L, 0xEA95);
     static_assert ( bar == 0xFAD7, "" );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/bitwise.operations/bit_xor.pass.cpp b/libcxx/test/std/utilities/function.objects/bitwise.operations/bit_xor.pass.cpp
index 757417a2cb53f9476262ac46b6b8f12c422a3ba1..070bd4c5f7b1c833f328bd01d36eae51a8fad240 100644
--- a/libcxx/test/std/utilities/function.objects/bitwise.operations/bit_xor.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/bitwise.operations/bit_xor.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::bit_xor<int> F;
@@ -61,4 +61,6 @@ int main()
     static_assert ( bar == 0xB246, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/bitwise.operations/transparent.pass.cpp b/libcxx/test/std/utilities/function.objects/bitwise.operations/transparent.pass.cpp
index c360a51b4e9e79219791c9218e43b94d144ea967..5ad0f233f19e91698421112686149c23cd3c7a96 100644
--- a/libcxx/test/std/utilities/function.objects/bitwise.operations/transparent.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/bitwise.operations/transparent.pass.cpp
@@ -22,7 +22,7 @@ public:
 };
 
 
-int main () {
+int main(int, char**) {
     static_assert ( !is_transparent<std::bit_and<int>>::value, "" );
     static_assert ( !is_transparent<std::bit_and<std::string>>::value, "" );
     static_assert (  is_transparent<std::bit_and<void>>::value, "" );
diff --git a/libcxx/test/std/utilities/function.objects/comparisons/constexpr_init.pass.cpp b/libcxx/test/std/utilities/function.objects/comparisons/constexpr_init.pass.cpp
index 7632dc580610e4f1f56f5e9436f59d2a83a92ba8..a0c41432ec434e6160a386b148f3c1b6e21aa0ff 100644
--- a/libcxx/test/std/utilities/function.objects/comparisons/constexpr_init.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/comparisons/constexpr_init.pass.cpp
@@ -42,6 +42,8 @@ static_assert(test_constexpr_context<int>(), "");
 static_assert(test_constexpr_context<void>(), "");
 
 
-int main() {
+int main(int, char**) {
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/comparisons/equal_to.pass.cpp b/libcxx/test/std/utilities/function.objects/comparisons/equal_to.pass.cpp
index 7ec8f66328d974e2a39b7699a3ff8ab10aed817f..beed574f89e683f4932070098875bd1c5b1fc515 100644
--- a/libcxx/test/std/utilities/function.objects/comparisons/equal_to.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/comparisons/equal_to.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::equal_to<int> F;
     const F f = F();
@@ -39,4 +39,6 @@ int main()
     constexpr bool bar = std::equal_to<> () (36.0, 36);
     static_assert ( bar, "" );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/comparisons/greater.pass.cpp b/libcxx/test/std/utilities/function.objects/comparisons/greater.pass.cpp
index 12111ef28e393c726e5d45f27af932a5cdc41903..35c05757c8ca77edd41a1ff8c729c7296dea5698 100644
--- a/libcxx/test/std/utilities/function.objects/comparisons/greater.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/comparisons/greater.pass.cpp
@@ -17,7 +17,7 @@
 #include "test_macros.h"
 #include "pointer_comparison_test_helper.hpp"
 
-int main()
+int main(int, char**)
 {
     typedef std::greater<int> F;
     const F f = F();
@@ -49,4 +49,6 @@ int main()
     constexpr bool bar = std::greater<> () (36.0, 36);
     static_assert ( !bar, "" );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/comparisons/greater_equal.pass.cpp b/libcxx/test/std/utilities/function.objects/comparisons/greater_equal.pass.cpp
index 1ac67eadc38aa3a72da7fda506183284ad43a703..9a6d36c4176b764ac5c45f773cfc058bbee6b798 100644
--- a/libcxx/test/std/utilities/function.objects/comparisons/greater_equal.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/comparisons/greater_equal.pass.cpp
@@ -17,7 +17,7 @@
 #include "test_macros.h"
 #include "pointer_comparison_test_helper.hpp"
 
-int main()
+int main(int, char**)
 {
     typedef std::greater_equal<int> F;
     const F f = F();
@@ -49,4 +49,6 @@ int main()
     constexpr bool bar = std::greater_equal<> () (36.0, 36);
     static_assert ( bar, "" );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/comparisons/less.pass.cpp b/libcxx/test/std/utilities/function.objects/comparisons/less.pass.cpp
index abfe09ad58d22fc8922c2fbde82ec9ed409773cf..31a2f975b1895c6a34f0973ecb5b3176bc9ebdc6 100644
--- a/libcxx/test/std/utilities/function.objects/comparisons/less.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/comparisons/less.pass.cpp
@@ -17,7 +17,7 @@
 #include "test_macros.h"
 #include "pointer_comparison_test_helper.hpp"
 
-int main()
+int main(int, char**)
 {
     typedef std::less<int> F;
     const F f = F();
@@ -48,4 +48,6 @@ int main()
     constexpr bool bar = std::less<> () (36.0, 36);
     static_assert ( !bar, "" );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/comparisons/less_equal.pass.cpp b/libcxx/test/std/utilities/function.objects/comparisons/less_equal.pass.cpp
index 2e733042409a24645dd4fc82fb033507e752e771..31cbed1717250f9bc7158507ce00e35d2cd8ffa3 100644
--- a/libcxx/test/std/utilities/function.objects/comparisons/less_equal.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/comparisons/less_equal.pass.cpp
@@ -17,7 +17,7 @@
 #include "test_macros.h"
 #include "pointer_comparison_test_helper.hpp"
 
-int main()
+int main(int, char**)
 {
     typedef std::less_equal<int> F;
     const F f = F();
@@ -49,4 +49,6 @@ int main()
     constexpr bool bar = std::less_equal<> () (36.0, 36);
     static_assert ( bar, "" );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/comparisons/not_equal_to.pass.cpp b/libcxx/test/std/utilities/function.objects/comparisons/not_equal_to.pass.cpp
index fd329157058d34ec96914819e278048f59480ee6..0e405de1be972ace1b5174fe6c01b2786fe50d24 100644
--- a/libcxx/test/std/utilities/function.objects/comparisons/not_equal_to.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/comparisons/not_equal_to.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::not_equal_to<int> F;
     const F f = F();
@@ -41,4 +41,6 @@ int main()
     constexpr bool bar = std::not_equal_to<> () (36.0, 36);
     static_assert ( !bar, "" );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/comparisons/transparent.pass.cpp b/libcxx/test/std/utilities/function.objects/comparisons/transparent.pass.cpp
index f3896770ec04dea41ba6f8456eaf91d170163331..4be81925b7f703f1a6659475fa45975f9952d990 100644
--- a/libcxx/test/std/utilities/function.objects/comparisons/transparent.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/comparisons/transparent.pass.cpp
@@ -22,7 +22,7 @@ public:
 };
 
 
-int main ()
+int main(int, char**)
 {
     static_assert ( !is_transparent<std::less<int>>::value, "" );
     static_assert ( !is_transparent<std::less<std::string>>::value, "" );
diff --git a/libcxx/test/std/utilities/function.objects/func.def/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/function.objects/func.def/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/function.objects/func.def/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.def/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.invoke/invoke.pass.cpp b/libcxx/test/std/utilities/function.objects/func.invoke/invoke.pass.cpp
index b0a41447e05a214a5f4ef175fbadd82a02faa80f..57350f16c40009499a5fce8a071ff62908e299d5 100644
--- a/libcxx/test/std/utilities/function.objects/func.invoke/invoke.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.invoke/invoke.pass.cpp
@@ -340,9 +340,11 @@ void noexcept_test() {
     }
 }
 
-int main() {
+int main(int, char**) {
     bullet_one_two_tests();
     bullet_three_four_tests();
     bullet_five_tests();
     noexcept_test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.invoke/invoke_feature_test_macro.pass.cpp b/libcxx/test/std/utilities/function.objects/func.invoke/invoke_feature_test_macro.pass.cpp
index f7f63a0bd8beb2d36261e565f1b186ca41c47bd4..b0404659d78c5f74a6a47a754b46297fd2ff2a80 100644
--- a/libcxx/test/std/utilities/function.objects/func.invoke/invoke_feature_test_macro.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.invoke/invoke_feature_test_macro.pass.cpp
@@ -31,8 +31,10 @@
 
 int foo(int) { return 42; }
 
-int main() {
+int main(int, char**) {
 #if defined(__cpp_lib_invoke)
   assert(std::invoke(foo, 101) == 42);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.memfn/member_data.fail.cpp b/libcxx/test/std/utilities/function.objects/func.memfn/member_data.fail.cpp
index 483f7a327c3d46a1bb5c03cf280b4e16ff8e9a02..130644fbd29eaab5ae1afd297a95f68a95bb0047 100644
--- a/libcxx/test/std/utilities/function.objects/func.memfn/member_data.fail.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.memfn/member_data.fail.cpp
@@ -35,7 +35,9 @@ test(F f)
     }
 }
 
-int main()
+int main(int, char**)
 {
     test(std::mem_fn(&A::data_));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.memfn/member_data.pass.cpp b/libcxx/test/std/utilities/function.objects/func.memfn/member_data.pass.cpp
index 75211ba21e0a7f4d0e4faa0e2ec91136b8bd0109..52581881a5b2cf9a75e152d7767152a4395c8bdb 100644
--- a/libcxx/test/std/utilities/function.objects/func.memfn/member_data.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.memfn/member_data.pass.cpp
@@ -36,7 +36,9 @@ test(F f)
     }
 }
 
-int main()
+int main(int, char**)
 {
     test(std::mem_fn(&A::data_));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.memfn/member_function.pass.cpp b/libcxx/test/std/utilities/function.objects/func.memfn/member_function.pass.cpp
index a04e49efa209ec54163ce1fc53cee0bfe6e62de5..a271c067008b9dcebd2a8477f69b11e738da34bb 100644
--- a/libcxx/test/std/utilities/function.objects/func.memfn/member_function.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.memfn/member_function.pass.cpp
@@ -65,7 +65,7 @@ test2(F f)
     }
 }
 
-int main()
+int main(int, char**)
 {
     test0(std::mem_fn(&A::test0));
     test1(std::mem_fn(&A::test1));
@@ -73,4 +73,6 @@ int main()
 #if TEST_STD_VER >= 11
     static_assert((noexcept(std::mem_fn(&A::test0))), ""); // LWG#2489
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.memfn/member_function_const.pass.cpp b/libcxx/test/std/utilities/function.objects/func.memfn/member_function_const.pass.cpp
index 9ea6531a2ec674500bb5af79bdfd708e0ce44d35..dc93196cdc39642ae14f8535e341460031d44515 100644
--- a/libcxx/test/std/utilities/function.objects/func.memfn/member_function_const.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.memfn/member_function_const.pass.cpp
@@ -69,9 +69,11 @@ test2(F f)
     }
 }
 
-int main()
+int main(int, char**)
 {
     test0(std::mem_fn(&A::test0));
     test1(std::mem_fn(&A::test1));
     test2(std::mem_fn(&A::test2));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.memfn/member_function_const_volatile.pass.cpp b/libcxx/test/std/utilities/function.objects/func.memfn/member_function_const_volatile.pass.cpp
index 9258c0a03f42549e6768f773c853f0a55f20dd8b..594e1de8ad631b6dbc0732ed0ea1fd757631a98c 100644
--- a/libcxx/test/std/utilities/function.objects/func.memfn/member_function_const_volatile.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.memfn/member_function_const_volatile.pass.cpp
@@ -69,9 +69,11 @@ test2(F f)
     }
 }
 
-int main()
+int main(int, char**)
 {
     test0(std::mem_fn(&A::test0));
     test1(std::mem_fn(&A::test1));
     test2(std::mem_fn(&A::test2));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.memfn/member_function_volatile.pass.cpp b/libcxx/test/std/utilities/function.objects/func.memfn/member_function_volatile.pass.cpp
index c22baecd9b82e9534b66cba061d7a20392a46842..04439387dfec9c0038f75d2ca87e54fd3ddabb2d 100644
--- a/libcxx/test/std/utilities/function.objects/func.memfn/member_function_volatile.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.memfn/member_function_volatile.pass.cpp
@@ -69,9 +69,11 @@ test2(F f)
     }
 }
 
-int main()
+int main(int, char**)
 {
     test0(std::mem_fn(&A::test0));
     test1(std::mem_fn(&A::test1));
     test2(std::mem_fn(&A::test2));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.not_fn/not_fn.pass.cpp b/libcxx/test/std/utilities/function.objects/func.not_fn/not_fn.pass.cpp
index c3adbf7ffc526f53cc87b75f8543d79e5e3bc609..a1c77841247ebb1136ee5cae1e5460647b8dfab6 100644
--- a/libcxx/test/std/utilities/function.objects/func.not_fn/not_fn.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.not_fn/not_fn.pass.cpp
@@ -602,7 +602,7 @@ void test_lwg2767() {
     }
 }
 
-int main()
+int main(int, char**)
 {
     constructor_tests();
     return_type_tests();
@@ -612,4 +612,6 @@ int main()
     call_operator_forwarding_test();
     call_operator_noexcept_test();
     test_lwg2767();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.require/INVOKE_tested_elsewhere.pass.cpp b/libcxx/test/std/utilities/function.objects/func.require/INVOKE_tested_elsewhere.pass.cpp
index 2bb9cb583710b39bfcbea19c1b9c95b9654caf2f..00b7d53be3a41fa5ab286b03c8b6a7a8d85fed1c 100644
--- a/libcxx/test/std/utilities/function.objects/func.require/INVOKE_tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.require/INVOKE_tested_elsewhere.pass.cpp
@@ -12,4 +12,6 @@
 // since they require calling the implementation specific "__invoke" and
 // "__invoke_constexpr" functions.
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/std/utilities/function.objects/func.require/binary_function.pass.cpp b/libcxx/test/std/utilities/function.objects/func.require/binary_function.pass.cpp
index 76ba44fc994842f8ff4c843ee375641cf4e8c2a7..79a4855ea02bd3330fff25d27599e3a243665ce4 100644
--- a/libcxx/test/std/utilities/function.objects/func.require/binary_function.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.require/binary_function.pass.cpp
@@ -15,10 +15,12 @@
 #include <functional>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     typedef std::binary_function<int, short, bool> bf;
     static_assert((std::is_same<bf::first_argument_type, int>::value), "");
     static_assert((std::is_same<bf::second_argument_type, short>::value), "");
     static_assert((std::is_same<bf::result_type, bool>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.require/unary_function.pass.cpp b/libcxx/test/std/utilities/function.objects/func.require/unary_function.pass.cpp
index 0d178b0dc6d47ac1f3476d6f4e68000fdedf55f9..f68b4b37c7332950922d9cc85305baf762c43ed4 100644
--- a/libcxx/test/std/utilities/function.objects/func.require/unary_function.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.require/unary_function.pass.cpp
@@ -15,9 +15,11 @@
 #include <functional>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     typedef std::unary_function<int, bool> uf;
     static_assert((std::is_same<uf::argument_type, int>::value), "");
     static_assert((std::is_same<uf::result_type, bool>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.search/func.search.bm/default.pass.cpp b/libcxx/test/std/utilities/function.objects/func.search/func.search.bm/default.pass.cpp
index 3293a3215ede73e5815b733606d1d6a4d95917d5..55cde8fe77764f5072230b145b0d5077829ab04d 100644
--- a/libcxx/test/std/utilities/function.objects/func.search/func.search.bm/default.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.search/func.search.bm/default.pass.cpp
@@ -122,7 +122,9 @@ test2()
     do_search(Iter1(ij), Iter1(ij+sj), Iter2(ik), Iter2(ik+sk), Iter1(ij+6));
 }
 
-int main() {
+int main(int, char**) {
     test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
     test2<random_access_iterator<const char*>, random_access_iterator<const char*> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.search/func.search.bm/hash.pass.cpp b/libcxx/test/std/utilities/function.objects/func.search/func.search.bm/hash.pass.cpp
index d0ce11b08bbb758d4702ed757c441bfa673decd1..106b0d37f61c938c5c895494cf1e76f878215b2a 100644
--- a/libcxx/test/std/utilities/function.objects/func.search/func.search.bm/hash.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.search/func.search.bm/hash.pass.cpp
@@ -118,7 +118,9 @@ test2()
     do_search(Iter1(ih), Iter1(ih+sh), Iter2(ii), Iter2(ii+3), Iter1(ih+3),  sh*3);
 }
 
-int main() {
+int main(int, char**) {
     test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
     test2<random_access_iterator<const char*>, random_access_iterator<const char*> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.search/func.search.bm/hash.pred.pass.cpp b/libcxx/test/std/utilities/function.objects/func.search/func.search.bm/hash.pred.pass.cpp
index 59178deb613336927d6f08266d39717144fb8bcf..be4db4e5a54181e90460488a379319a8f2c9b92f 100644
--- a/libcxx/test/std/utilities/function.objects/func.search/func.search.bm/hash.pred.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.search/func.search.bm/hash.pred.pass.cpp
@@ -136,7 +136,9 @@ test2()
     do_search(Iter1(ih), Iter1(ih+sh), Iter2(ii), Iter2(ii+3), Iter1(ih+3),  sh*3);
 }
 
-int main() {
+int main(int, char**) {
     test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
     test2<random_access_iterator<const char*>, random_access_iterator<const char*> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.search/func.search.bm/pred.pass.cpp b/libcxx/test/std/utilities/function.objects/func.search/func.search.bm/pred.pass.cpp
index 7f3e837a70ebf6fd7835c262bd7fa70883b99d17..3656caa8749882f1fcea67c6d679589ab90c6fce 100644
--- a/libcxx/test/std/utilities/function.objects/func.search/func.search.bm/pred.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.search/func.search.bm/pred.pass.cpp
@@ -127,7 +127,9 @@ test2()
     do_search(Iter1(ih), Iter1(ih+sh), Iter2(ii), Iter2(ii+3), Iter1(ih+3),  sh*3);
 }
 
-int main() {
+int main(int, char**) {
     test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
     test2<random_access_iterator<const char*>, random_access_iterator<const char*> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.search/func.search.bmh/default.pass.cpp b/libcxx/test/std/utilities/function.objects/func.search/func.search.bmh/default.pass.cpp
index 04adb178bf1fcab2758916534c4aaf94f06fe8f0..0b345deedc1c35340186ba9b25511b631486e2ca 100644
--- a/libcxx/test/std/utilities/function.objects/func.search/func.search.bmh/default.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.search/func.search.bmh/default.pass.cpp
@@ -122,7 +122,9 @@ test2()
     do_search(Iter1(ij), Iter1(ij+sj), Iter2(ik), Iter2(ik+sk), Iter1(ij+6));
 }
 
-int main() {
+int main(int, char**) {
     test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
     test2<random_access_iterator<const char*>, random_access_iterator<const char*> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.search/func.search.bmh/hash.pass.cpp b/libcxx/test/std/utilities/function.objects/func.search/func.search.bmh/hash.pass.cpp
index dca69117583533100e0677bd9f2ceb9126d73252..4106c5d6ae7fb08e9d1a7a7c9eae0927f74df06c 100644
--- a/libcxx/test/std/utilities/function.objects/func.search/func.search.bmh/hash.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.search/func.search.bmh/hash.pass.cpp
@@ -117,7 +117,9 @@ test2()
     do_search(Iter1(ih), Iter1(ih+sh), Iter2(ii), Iter2(ii+3), Iter1(ih+3),  sh*3);
 }
 
-int main() {
+int main(int, char**) {
     test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
     test2<random_access_iterator<const char*>, random_access_iterator<const char*> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.search/func.search.bmh/hash.pred.pass.cpp b/libcxx/test/std/utilities/function.objects/func.search/func.search.bmh/hash.pred.pass.cpp
index 6a5c215a7fd0bb246348064d254279e56e804961..757bcc75792c8f887bcda3807d5e2bc0aeba1b2c 100644
--- a/libcxx/test/std/utilities/function.objects/func.search/func.search.bmh/hash.pred.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.search/func.search.bmh/hash.pred.pass.cpp
@@ -130,7 +130,9 @@ test2()
     do_search(Iter1(ih), Iter1(ih+sh), Iter2(ii), Iter2(ii+3), Iter1(ih+3),  sh*3);
 }
 
-int main() {
+int main(int, char**) {
     test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
     test2<random_access_iterator<const char*>, random_access_iterator<const char*> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.search/func.search.bmh/pred.pass.cpp b/libcxx/test/std/utilities/function.objects/func.search/func.search.bmh/pred.pass.cpp
index 27c3d0c82c25bf0f97b571b388d6e9c29ee98c04..3a20b88512faeb49799e90f90b28f87f7d5bc705 100644
--- a/libcxx/test/std/utilities/function.objects/func.search/func.search.bmh/pred.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.search/func.search.bmh/pred.pass.cpp
@@ -124,7 +124,9 @@ test2()
     do_search(Iter1(ih), Iter1(ih+sh), Iter2(ii), Iter2(ii+3), Iter1(ih+3),  sh*3);
 }
 
-int main() {
+int main(int, char**) {
     test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
     test2<random_access_iterator<const char*>, random_access_iterator<const char*> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.search/func.search.default/default.pass.cpp b/libcxx/test/std/utilities/function.objects/func.search/func.search.default/default.pass.cpp
index 098b8ac113df204caaf66e1ad72355236b5e2d8f..eaf5eeb8273fcbac4866f69c22a1bd482b230fa6 100644
--- a/libcxx/test/std/utilities/function.objects/func.search/func.search.default/default.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.search/func.search.default/default.pass.cpp
@@ -82,7 +82,7 @@ test()
     do_search(Iter1(ij), Iter1(ij+sj), Iter2(ik), Iter2(ik+sk), Iter1(ij+6));
 }
 
-int main() {
+int main(int, char**) {
     test<forward_iterator<const int*>, forward_iterator<const int*> >();
     test<forward_iterator<const int*>, bidirectional_iterator<const int*> >();
     test<forward_iterator<const int*>, random_access_iterator<const int*> >();
@@ -92,4 +92,6 @@ int main() {
     test<random_access_iterator<const int*>, forward_iterator<const int*> >();
     test<random_access_iterator<const int*>, bidirectional_iterator<const int*> >();
     test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.search/func.search.default/default.pred.pass.cpp b/libcxx/test/std/utilities/function.objects/func.search/func.search.default/default.pred.pass.cpp
index 4b0f016d712fc97a6ffb3d153ba8ea1dec7e08be..773336f662664d04ffac1536c6d8b7a2c2bcb5f5 100644
--- a/libcxx/test/std/utilities/function.objects/func.search/func.search.default/default.pred.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.search/func.search.default/default.pred.pass.cpp
@@ -89,7 +89,7 @@ test()
     do_search(Iter1(ih), Iter1(ih+sh), Iter2(ii), Iter2(ii+3), Iter1(ih+3),  sh*3);
 }
 
-int main() {
+int main(int, char**) {
     test<forward_iterator<const int*>, forward_iterator<const int*> >();
     test<forward_iterator<const int*>, bidirectional_iterator<const int*> >();
     test<forward_iterator<const int*>, random_access_iterator<const int*> >();
@@ -99,4 +99,6 @@ int main() {
     test<random_access_iterator<const int*>, forward_iterator<const int*> >();
     test<random_access_iterator<const int*>, bidirectional_iterator<const int*> >();
     test<random_access_iterator<const int*>, random_access_iterator<const int*> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.search/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/function.objects/func.search/nothing_to_do.pass.cpp
index 02fe32ece48416fad2068b044f9fe906156a9706..779762e7e995d09895bcb7478575e11ceca209d6 100644
--- a/libcxx/test/std/utilities/function.objects/func.search/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.search/nothing_to_do.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.badcall/bad_function_call.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.badcall/bad_function_call.pass.cpp
index 2ec1d53c56e9d36c697861a9a1b3026726220833..eb223b88e4908a0e42457bd7c1f5e194c2341372 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.badcall/bad_function_call.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.badcall/bad_function_call.pass.cpp
@@ -19,7 +19,9 @@
 #include <functional>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::exception, std::bad_function_call>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.badcall/func.wrap.badcall.const/bad_function_call_ctor.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.badcall/func.wrap.badcall.const/bad_function_call_ctor.pass.cpp
index 6b6ee8a64a76d27361e662c5d09bb39701249c46..385919227e05660d4d70cb863783656d7b6a2a7b 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.badcall/func.wrap.badcall.const/bad_function_call_ctor.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.badcall/func.wrap.badcall.const/bad_function_call_ctor.pass.cpp
@@ -13,7 +13,9 @@
 #include <functional>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     std::bad_function_call ex;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/derive_from.fail.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/derive_from.fail.cpp
index 50fb4f19d5b5cc7e265b64fdabeba73165fe8ada..2a34eff92e2de1b2e50c947a43ca48f82bced975 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/derive_from.fail.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/derive_from.fail.cpp
@@ -18,7 +18,9 @@
 
 struct S : public std::function<void()> { using function::function; };
 
-int main() {
+int main(int, char**) {
    S f1( [](){} );
    S f2(std::allocator_arg, std::allocator<int>{}, f1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/derive_from.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/derive_from.pass.cpp
index 8c50c284b4275248ff2dbedf98cdb3b0e0f7ac63..70f68d2f49b71c0df5aacf9d87349d77713e0881 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/derive_from.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/derive_from.pass.cpp
@@ -20,10 +20,12 @@
 using Fn = std::function<void()>;
 struct S : public std::function<void()> { using function::function; };
 
-int main() {
+int main(int, char**) {
     S s( [](){} );
     S f1( s );
 #if TEST_STD_VER <= 14
     S f2(std::allocator_arg, std::allocator<int>{}, s);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.alg/swap.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.alg/swap.pass.cpp
index b6dbcab5301b05172bcb5488a4485a2a55e6b374..ec25bdf7802bae0b214a2bb566c7d399913a0f83 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.alg/swap.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.alg/swap.pass.cpp
@@ -57,7 +57,7 @@ int A::count = 0;
 int g(int) {return 0;}
 int h(int) {return 1;}
 
-int main()
+int main(int, char**)
 {
     assert(globalMemCounter.checkOutstandingNewEq(0));
     {
@@ -132,4 +132,6 @@ int main()
     }
     assert(A::count == 0);
     assert(globalMemCounter.checkOutstandingNewEq(0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.cap/operator_bool.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.cap/operator_bool.pass.cpp
index 1b55baa02e1afcbafe4c05492d1342163a6d4bda..ab5eef37270cf272992e5ff8ee6fa4199ffcb105 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.cap/operator_bool.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.cap/operator_bool.pass.cpp
@@ -17,7 +17,7 @@
 
 int g(int) {return 0;}
 
-int main()
+int main(int, char**)
 {
     {
     std::function<int(int)> f;
@@ -25,4 +25,6 @@ int main()
     f = g;
     assert(f);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/F.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/F.pass.cpp
index c32baebb51d0cf609d54435577b75c766c749979..fe5d24806b70e096661b532758fff865dabfc71c 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/F.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/F.pass.cpp
@@ -60,7 +60,7 @@ struct LValueCallable {
 };
 #endif
 
-int main()
+int main(int, char**)
 {
     assert(globalMemCounter.checkOutstandingNewEq(0));
     {
@@ -111,4 +111,6 @@ int main()
         static_assert(!std::is_constructible<Fn, RValueCallable>::value, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/F_assign.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/F_assign.pass.cpp
index abff663cb72cefe6caf135962f2e6353229000d6..f70a2087cc2effd792f9085b271b757ee111d02f 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/F_assign.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/F_assign.pass.cpp
@@ -63,7 +63,7 @@ struct LValueCallable {
 };
 #endif
 
-int main()
+int main(int, char**)
 {
     assert(globalMemCounter.checkOutstandingNewEq(0));
     {
@@ -115,4 +115,6 @@ int main()
         static_assert(!std::is_assignable<Fn&, RValueCallable>::value, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/F_incomplete.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/F_incomplete.pass.cpp
index 1598486661cffaaf77150e238f6936ae43f480fc..21c2f216efe8b0b687c130cf91a4fb272261f4dc 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/F_incomplete.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/F_incomplete.pass.cpp
@@ -58,6 +58,8 @@ void test_pr34298()
   }
 }
 
-int main() {
+int main(int, char**) {
   test_pr34298();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/F_nullptr.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/F_nullptr.pass.cpp
index 89b7876235ec196de8d009c2598c8e8bac269ca0..ebea3d0aa954661d80eb6aab35292b88e80cbc9e 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/F_nullptr.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/F_nullptr.pass.cpp
@@ -239,8 +239,10 @@ void test_md() {
     test_imp<int MemData::*, int(MemData&)>();
 }
 
-int main() {
+int main(int, char**) {
     test_func();
     test_mf();
     test_md();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc.fail.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc.fail.cpp
index acbeb9f9c9883c8f8481fb72448d9146f029b800..50a11fb81989e9b7f376bb80ee0913839f3fd8fe 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc.fail.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc.fail.cpp
@@ -18,7 +18,9 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     std::function<int(int)> f(std::allocator_arg, std::allocator<int>());
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc.pass.cpp
index b048109e54ba9ae9c69e19ee8ef9d48ab17d2313..3b37ce6ffdc33e3cb964bc17cb5fc94d48fa7629 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc.pass.cpp
@@ -20,10 +20,12 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::function<int(int)> f(std::allocator_arg, bare_allocator<int>());
     assert(!f);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_F.fail.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_F.fail.cpp
index bddc92787192d7024c7c1652cdafacdad6bf0549..c31c0a21f32c26c9e258ca2405a1443b96091e36 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_F.fail.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_F.fail.cpp
@@ -22,7 +22,9 @@
 
 void foo(int) {}
 
-int main()
+int main(int, char**)
 {
     std::function<void(int)> f(std::allocator_arg, std::allocator<int>(), foo);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_F.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_F.pass.cpp
index 4d49434f3170d2a918428564aa11b3998e309aff..6fa0d6faeaf08ce882220aed0775b42c9e892ce0 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_F.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_F.pass.cpp
@@ -106,7 +106,7 @@ void test_for_alloc(Alloc& alloc) {
     test_MemFunClass<int(MemFunClass::*)(int, int) const, int(MemFunClass&, int, int)>(alloc);
 }
 
-int main()
+int main(int, char**)
 {
     {
         bare_allocator<DummyClass> bare_alloc;
@@ -126,4 +126,6 @@ int main()
     }
 #endif
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_function.fail.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_function.fail.cpp
index b6703c0b7b9259c19bf50f7d242fd4bd05899d46..621588f8156c6949040010b4dc13c7ab7725625b 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_function.fail.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_function.fail.cpp
@@ -21,9 +21,11 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::function<void(int)> F;
     F f1;
     F f2(std::allocator_arg, std::allocator<int>(), f1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_function.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_function.pass.cpp
index 39050e6f1534f75056db05e89129fa96cacc42fc..583ca162ebf3b9b486297b89364c32b91ead4be4 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_function.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_function.pass.cpp
@@ -111,7 +111,7 @@ void test_for_alloc(Alloc& alloc)
     test_MemFunClass<int(MemFunClass::*)(int, int) const, int(MemFunClass&, int, int)>(alloc);
 }
 
-int main()
+int main(int, char**)
 {
   {
     bare_allocator<DummyClass> alloc;
@@ -121,4 +121,6 @@ int main()
     non_default_test_allocator<DummyClass> alloc(42);
     test_for_alloc(alloc);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_nullptr.fail.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_nullptr.fail.cpp
index 32d19ebf7049c4c93b45bf9d220d055788bd1bd3..52bc528fe591f9015387ab1f5e6fa5a49bb541c1 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_nullptr.fail.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_nullptr.fail.cpp
@@ -20,7 +20,9 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     std::function<int(int)> f(std::allocator_arg, std::allocator<int>(), nullptr);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_nullptr.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_nullptr.pass.cpp
index 6378a6cd9d346e9f5bd256f93b82030f8f2c10a0..653057f6ec9e0dd4bbeaad42ec9d4c8e0e9ba8c2 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_nullptr.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_nullptr.pass.cpp
@@ -20,8 +20,10 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     std::function<int(int)> f(std::allocator_arg, bare_allocator<int>(), nullptr);
     assert(!f);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_rfunction.fail.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_rfunction.fail.cpp
index 558b7814cedaea0ef12f11ae81a4d06c8ade478b..643cad8f074211a834719bb92097fe7e2e73efc6 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_rfunction.fail.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_rfunction.fail.cpp
@@ -50,10 +50,12 @@ int A::count = 0;
 
 int g(int) { return 0; }
 
-int main()
+int main(int, char**)
 {
     {
         std::function<int(int)> f = A();
         std::function<int(int)> f2(std::allocator_arg, std::allocator<A>(), std::move(f));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_rfunction.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_rfunction.pass.cpp
index 8f379e3030592d2d789c3ee46f46d308459763c3..064046d0b2dd3ca72c18ed2ffe32a8a7d052cb02 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_rfunction.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_rfunction.pass.cpp
@@ -54,7 +54,7 @@ int A::count = 0;
 
 int g(int) { return 0; }
 
-int main()
+int main(int, char**)
 {
     assert(globalMemCounter.checkOutstandingNewEq(0));
     {
@@ -105,4 +105,6 @@ int main()
         assert(f2.target<Ptr>());
         assert(f.target<Ptr>()); // f is unchanged because the target is small
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/copy_assign.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/copy_assign.pass.cpp
index df2a43aba9dd95b9dc41c01c44cd42a5adb6ceff..d7b11ae1bfdde13112c70b42ccbdea7287647529 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/copy_assign.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/copy_assign.pass.cpp
@@ -48,7 +48,7 @@ int g(int) { return 0; }
 int g2(int, int) { return 2; }
 int g3(int, int, int) { return 3; }
 
-int main() {
+int main(int, char**) {
   assert(globalMemCounter.checkOutstandingNewEq(0));
   {
     std::function<int(int)> f = A();
@@ -134,4 +134,6 @@ int main() {
     assert(f.target<int (*)(int)>() == 0);
   }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/copy_move.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/copy_move.pass.cpp
index 9f03ee7a1f9ba50236588b84969674bcc3bb81e4..dbbde5ce473569a8178931cffca2aa3d0c94a1f8 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/copy_move.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/copy_move.pass.cpp
@@ -50,7 +50,7 @@ int A::count = 0;
 
 int g(int) {return 0;}
 
-int main()
+int main(int, char**)
 {
     assert(globalMemCounter.checkOutstandingNewEq(0));
     {
@@ -161,4 +161,6 @@ int main()
         LIBCPP_ASSERT(f.target<Ptr>()); // f is unchanged because the target is small
     }
 #endif  // TEST_STD_VER >= 11
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/default.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/default.pass.cpp
index 06ea4e058d06d1c0b18e6e66a8e11ba22881da7f..46c14ce368b8527f775008f7a93a5c97eb21fe80 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/default.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/default.pass.cpp
@@ -15,8 +15,10 @@
 #include <functional>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::function<int(int)> f;
     assert(!f);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/move_reentrant.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/move_reentrant.pass.cpp
index 026cfc2d48449d088b2a2986f6ec283e2ff6064d..e15fbbaae54db51fde86869f99d8313600b23383 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/move_reentrant.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/move_reentrant.pass.cpp
@@ -33,7 +33,7 @@ struct A
 std::function<void()> A::global;
 bool A::cancel = false;
 
-int main()
+int main(int, char**)
 {
   A::global = A();
   assert(A::global.target<A>());
@@ -42,4 +42,6 @@ int main()
   A::cancel = true;
   A::global = std::function<void()>(nullptr);
   assert(!A::global.target<A>());
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/nullptr_t.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/nullptr_t.pass.cpp
index b685d53bfa092d13cf7eee89ec94f5cab200ed25..d58e191c4709a8f293cf4b4fceaf6cdaa6af9cc3 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/nullptr_t.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/nullptr_t.pass.cpp
@@ -15,8 +15,10 @@
 #include <functional>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::function<int(int)> f(nullptr);
     assert(!f);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/nullptr_t_assign.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/nullptr_t_assign.pass.cpp
index 7a8d3e380e2a57c68db285b95f72eb8b6a363fbd..ff81080ffdaf17b498b0f1ed88f5362d1ca4279c 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/nullptr_t_assign.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/nullptr_t_assign.pass.cpp
@@ -46,7 +46,7 @@ int A::count = 0;
 
 int g(int) {return 0;}
 
-int main()
+int main(int, char**)
 {
     assert(globalMemCounter.checkOutstandingNewEq(0));
     {
@@ -68,4 +68,6 @@ int main()
     assert(globalMemCounter.checkOutstandingNewEq(0));
     assert(f.target<int(*)(int)>() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/nullptr_t_assign_reentrant.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/nullptr_t_assign_reentrant.pass.cpp
index c4006a7c9fd24547705d5bcf19dc5e07ddc876d6..def86085ddb42558391df0ddcc7e2b3337801bf2 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/nullptr_t_assign_reentrant.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/nullptr_t_assign_reentrant.pass.cpp
@@ -33,7 +33,7 @@ struct A
 std::function<void()> A::global;
 bool A::cancel = false;
 
-int main()
+int main(int, char**)
 {
   A::global = A();
   assert(A::global.target<A>());
@@ -42,4 +42,6 @@ int main()
   A::cancel = true;
   A::global = nullptr;
   assert(!A::global.target<A>());
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.inv/invoke.fail.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.inv/invoke.fail.cpp
index 5f91e5c87d9d61b9e8adfa321fe6dd46a2852617..0f8e051d4067c6fbf098dfa44d8fe6671f9fe790 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.inv/invoke.fail.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.inv/invoke.fail.cpp
@@ -39,7 +39,9 @@ test_int_1()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test_int_1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.inv/invoke.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.inv/invoke.pass.cpp
index 7775cad67736bac0b8ca9d9025c51d76a4da4f47..fb67a3abf4adae73fa711923395a5a975d4dc973 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.inv/invoke.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.inv/invoke.pass.cpp
@@ -401,7 +401,7 @@ void test_int_2()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test_void_0();
     test_int_0();
@@ -409,4 +409,6 @@ int main()
     test_int_1();
     test_void_2();
     test_int_2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.mod/assign_F_alloc.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.mod/assign_F_alloc.pass.cpp
index 5a6f503a28498cb973c8ef362d8e3a8eb5893273..8ddd1cd2b187c636040546e4d7c304b8ee3fa047 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.mod/assign_F_alloc.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.mod/assign_F_alloc.pass.cpp
@@ -48,7 +48,7 @@ public:
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
 #if TEST_STD_VER <= 14
     {
@@ -60,4 +60,6 @@ int main()
     }
     assert(A::count == 0);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.mod/swap.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.mod/swap.pass.cpp
index a75aee33048a09262a8a33c0a03a48cf4df2e0b4..93997a0b55f8f5e7810cfb42dba72a37c7439a57 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.mod/swap.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.mod/swap.pass.cpp
@@ -57,7 +57,7 @@ int h(int) { return 1; }
 int g2(int, int) { return 2; }
 int g3(int, int, int) { return 3; }
 
-int main() {
+int main(int, char**) {
   assert(globalMemCounter.checkOutstandingNewEq(0));
   {
     std::function<int(int)> f1 = A(1);
@@ -189,4 +189,6 @@ int main() {
   }
   assert(globalMemCounter.checkOutstandingNewEq(0));
   assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.nullptr/operator_==.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.nullptr/operator_==.pass.cpp
index c68a1ca8262b77973cbd3609ed649b0be3c7c4ac..698a461c8f0312e0b7c4fa5cd845f824e0848326 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.nullptr/operator_==.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.nullptr/operator_==.pass.cpp
@@ -27,7 +27,7 @@
 
 int g(int) {return 0;}
 
-int main()
+int main(int, char**)
 {
     {
     std::function<int(int)> f;
@@ -37,4 +37,6 @@ int main()
     assert(f != nullptr);
     assert(nullptr != f);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.targ/target.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.targ/target.pass.cpp
index 7b59b56d092135064cdc33d6c35eab80253813c4..d5031ba06e77c2885c939c2a3967f3ac164da33a 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.targ/target.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.targ/target.pass.cpp
@@ -55,7 +55,7 @@ int A::count = 0;
 
 int g(int) {return 0;}
 
-int main()
+int main(int, char**)
 {
     {
     std::function<int(int)> f = A();
@@ -89,4 +89,6 @@ int main()
     assert(f.target<int>() == nullptr);
     }
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.targ/target_type.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.targ/target_type.pass.cpp
index 52d07a45a5084c3c6e99bbe52e1e4db59042709a..d9c8fc48d758af7a7d9e1eb9f2f8e891c4646318 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.targ/target_type.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.targ/target_type.pass.cpp
@@ -47,7 +47,7 @@ int A::count = 0;
 
 int g(int) {return 0;}
 
-int main()
+int main(int, char**)
 {
     {
     std::function<int(int)> f = A();
@@ -57,4 +57,6 @@ int main()
     std::function<int(int)> f;
     assert(f.target_type() == typeid(void));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/types.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/types.pass.cpp
index 496dee8ae750861b512a14890a6a39a1e5e5dcc9..8083ad83ac0cf5b9c95d3d5c8a94a0a28135873b 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/types.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/func.wrap.func/types.pass.cpp
@@ -98,10 +98,12 @@ void test_other_function ()
     static_assert((!has_second_argument_type<F>::value), "" );
 }
 
-int main()
+int main(int, char**)
 {
     test_nullary_function<std::function<int()>, int>();
     test_unary_function  <std::function<double(int)>, double, int>();
     test_binary_function <std::function<double(int, char)>, double, int, char>();
     test_other_function  <std::function<double(int, char, double)>, double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/func.wrap/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/function.objects/func.wrap/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/function.objects/func.wrap/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/func.wrap/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/logical.operations/logical_and.pass.cpp b/libcxx/test/std/utilities/function.objects/logical.operations/logical_and.pass.cpp
index 1b0a1c63f16c8ed74c22b5831bb6a78a4444e023..29767a58c48bc7aabec10bbe112635e4ac9f7708 100644
--- a/libcxx/test/std/utilities/function.objects/logical.operations/logical_and.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/logical.operations/logical_and.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::logical_and<int> F;
     const F f = F();
@@ -48,4 +48,6 @@ int main()
     constexpr bool bar = std::logical_and<> () (36.0, 36);
     static_assert ( bar, "" );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/logical.operations/logical_not.pass.cpp b/libcxx/test/std/utilities/function.objects/logical.operations/logical_not.pass.cpp
index 2c0c9f3bc900112b7d403298000c9a297a200ed5..e93fd06fdd5aa3dca1e05ba0c257bef20ab24005 100644
--- a/libcxx/test/std/utilities/function.objects/logical.operations/logical_not.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/logical.operations/logical_not.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::logical_not<int> F;
     const F f = F();
@@ -38,4 +38,6 @@ int main()
     constexpr bool bar = std::logical_not<> () (36);
     static_assert ( !bar, "" );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/logical.operations/logical_or.pass.cpp b/libcxx/test/std/utilities/function.objects/logical.operations/logical_or.pass.cpp
index 497a9d981f1e221814948bfc68a9153f01c46ac4..abe536572ea43c93e277e52648d32eae796766bf 100644
--- a/libcxx/test/std/utilities/function.objects/logical.operations/logical_or.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/logical.operations/logical_or.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::logical_or<int> F;
     const F f = F();
@@ -47,4 +47,6 @@ int main()
     constexpr bool bar = std::logical_or<> () (36.0, 36);
     static_assert ( bar, "" );
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/logical.operations/transparent.pass.cpp b/libcxx/test/std/utilities/function.objects/logical.operations/transparent.pass.cpp
index 3aa24c44330453f516804e6c21c5fdfa4ea556f1..eb590b31a014e052ccb4b8df3dc180919bb97878 100644
--- a/libcxx/test/std/utilities/function.objects/logical.operations/transparent.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/logical.operations/transparent.pass.cpp
@@ -22,7 +22,7 @@ public:
 };
 
 
-int main ()
+int main(int, char**)
 {
     static_assert ( !is_transparent<std::logical_and<int>>::value, "" );
     static_assert ( !is_transparent<std::logical_and<std::string>>::value, "" );
diff --git a/libcxx/test/std/utilities/function.objects/negators/binary_negate.depr_in_cxx17.fail.cpp b/libcxx/test/std/utilities/function.objects/negators/binary_negate.depr_in_cxx17.fail.cpp
index ca8b76711cf353a3070c0ff19ae9dde6adf98f61..713afc6656268e94dda23a572000c95534335b8d 100644
--- a/libcxx/test/std/utilities/function.objects/negators/binary_negate.depr_in_cxx17.fail.cpp
+++ b/libcxx/test/std/utilities/function.objects/negators/binary_negate.depr_in_cxx17.fail.cpp
@@ -28,7 +28,9 @@ struct Predicate {
     bool operator()(first_argument_type, second_argument_type) const { return true; }
 };
 
-int main() {
+int main(int, char**) {
     std::binary_negate<Predicate> f((Predicate())); // expected-error{{'binary_negate<Predicate>' is deprecated}}
     (void)f;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/negators/binary_negate.pass.cpp b/libcxx/test/std/utilities/function.objects/negators/binary_negate.pass.cpp
index 1e7edcb3242681fa2930625ce21b7c83c9646d06..41541c10ff1eb7294f8342a5fdf8e375f1f02370 100644
--- a/libcxx/test/std/utilities/function.objects/negators/binary_negate.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/negators/binary_negate.pass.cpp
@@ -14,7 +14,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::binary_negate<std::logical_and<int> > F;
     const F f = F(std::logical_and<int>());
@@ -25,4 +25,6 @@ int main()
     assert( f(36, 0));
     assert( f(0, 36));
     assert( f(0, 0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/negators/not1.depr_in_cxx17.fail.cpp b/libcxx/test/std/utilities/function.objects/negators/not1.depr_in_cxx17.fail.cpp
index 9fbe6db66f92578470517f9367144bc5a333391d..407cbd4fc2648e2765d4a6908b653bbd06c76d07 100644
--- a/libcxx/test/std/utilities/function.objects/negators/not1.depr_in_cxx17.fail.cpp
+++ b/libcxx/test/std/utilities/function.objects/negators/not1.depr_in_cxx17.fail.cpp
@@ -27,6 +27,8 @@ struct Predicate {
     bool operator()(argument_type) const { return true; }
 };
 
-int main() {
+int main(int, char**) {
     std::not1(Predicate()); // expected-error{{'not1<Predicate>' is deprecated}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/negators/not1.pass.cpp b/libcxx/test/std/utilities/function.objects/negators/not1.pass.cpp
index 33268222b5d9a965b8f4f94bbe67fcda307cc0b9..07c160a97abf1fa4254fc067565f8e1e5e2a9727 100644
--- a/libcxx/test/std/utilities/function.objects/negators/not1.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/negators/not1.pass.cpp
@@ -13,9 +13,11 @@
 #include <functional>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::logical_not<int> F;
     assert(std::not1(F())(36));
     assert(!std::not1(F())(0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/negators/not2.depr_in_cxx17.fail.cpp b/libcxx/test/std/utilities/function.objects/negators/not2.depr_in_cxx17.fail.cpp
index 032ce3429dc169b64f68ca9d04d12c98798fcd51..24178e0a05dca06311bc53e24f817d708ab7fcf3 100644
--- a/libcxx/test/std/utilities/function.objects/negators/not2.depr_in_cxx17.fail.cpp
+++ b/libcxx/test/std/utilities/function.objects/negators/not2.depr_in_cxx17.fail.cpp
@@ -28,6 +28,8 @@ struct Predicate {
     bool operator()(first_argument_type, second_argument_type) const { return true; }
 };
 
-int main() {
+int main(int, char**) {
     std::not2(Predicate()); // expected-error{{'not2<Predicate>' is deprecated}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/negators/not2.pass.cpp b/libcxx/test/std/utilities/function.objects/negators/not2.pass.cpp
index 208d33b4a3eaa81cd493f54b3477828959149e42..d9f3c95fd89691fa3430c02da786affc9805c74d 100644
--- a/libcxx/test/std/utilities/function.objects/negators/not2.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/negators/not2.pass.cpp
@@ -13,11 +13,13 @@
 #include <functional>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::logical_and<int> F;
     assert(!std::not2(F())(36, 36));
     assert( std::not2(F())(36, 0));
     assert( std::not2(F())(0, 36));
     assert( std::not2(F())(0, 0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/negators/unary_negate.depr_in_cxx17.fail.cpp b/libcxx/test/std/utilities/function.objects/negators/unary_negate.depr_in_cxx17.fail.cpp
index 99cdf136d6422f024e1d07e70b3272d9087fd731..15a0a277826eaaa9128bffe620fea92c05aef8c8 100644
--- a/libcxx/test/std/utilities/function.objects/negators/unary_negate.depr_in_cxx17.fail.cpp
+++ b/libcxx/test/std/utilities/function.objects/negators/unary_negate.depr_in_cxx17.fail.cpp
@@ -27,7 +27,9 @@ struct Predicate {
     bool operator()(argument_type) const { return true; }
 };
 
-int main() {
+int main(int, char**) {
     std::unary_negate<Predicate> f((Predicate())); // expected-error{{'unary_negate<Predicate>' is deprecated}}
     (void)f;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/negators/unary_negate.pass.cpp b/libcxx/test/std/utilities/function.objects/negators/unary_negate.pass.cpp
index ec00c3e32a2f0bd2d4486e543287995c41a8a431..54fd54f396934f67e1b30aeaefaac1c57e9390eb 100644
--- a/libcxx/test/std/utilities/function.objects/negators/unary_negate.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/negators/unary_negate.pass.cpp
@@ -14,7 +14,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::unary_negate<std::logical_not<int> > F;
     const F f = F(std::logical_not<int>());
@@ -22,4 +22,6 @@ int main()
     static_assert((std::is_same<F::result_type, bool>::value), "" );
     assert(f(36));
     assert(!f(0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/refwrap/refwrap.access/conversion.pass.cpp b/libcxx/test/std/utilities/function.objects/refwrap/refwrap.access/conversion.pass.cpp
index 5e67db520fb55262b0d8e2b2fd9b8eb793a6a655..c15989f003e705d252a86125686bc7d716f78c64 100644
--- a/libcxx/test/std/utilities/function.objects/refwrap/refwrap.access/conversion.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/refwrap/refwrap.access/conversion.pass.cpp
@@ -30,7 +30,7 @@ test(T& t)
 
 void f() {}
 
-int main()
+int main(int, char**)
 {
     void (*fp)() = f;
     test(fp);
@@ -41,4 +41,6 @@ int main()
     test(i);
     const int j = 0;
     test(j);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/refwrap/refwrap.assign/copy_assign.pass.cpp b/libcxx/test/std/utilities/function.objects/refwrap/refwrap.assign/copy_assign.pass.cpp
index 16ce961126cbf5c84f8934ab92a03b8328947124..3ef0cdda8696f37bbb6aacdbfc878aae107cc028 100644
--- a/libcxx/test/std/utilities/function.objects/refwrap/refwrap.assign/copy_assign.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/refwrap/refwrap.assign/copy_assign.pass.cpp
@@ -42,7 +42,7 @@ test_function()
     assert(&r2.get() == &f);
 }
 
-int main()
+int main(int, char**)
 {
     void (*fp)() = f;
     test(fp);
@@ -53,4 +53,6 @@ int main()
     test(i);
     const int j = 0;
     test(j);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/refwrap/refwrap.const/copy_ctor.pass.cpp b/libcxx/test/std/utilities/function.objects/refwrap/refwrap.const/copy_ctor.pass.cpp
index 64726b53ef8780835c58830a05e0aac2df1b3395..355047d98ceba6f6de12d2fa9b34cfa59e4f5728 100644
--- a/libcxx/test/std/utilities/function.objects/refwrap/refwrap.const/copy_ctor.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/refwrap/refwrap.const/copy_ctor.pass.cpp
@@ -30,7 +30,7 @@ test(T& t)
 
 void f() {}
 
-int main()
+int main(int, char**)
 {
     void (*fp)() = f;
     test(fp);
@@ -41,4 +41,6 @@ int main()
     test(i);
     const int j = 0;
     test(j);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/refwrap/refwrap.const/type_ctor.fail.cpp b/libcxx/test/std/utilities/function.objects/refwrap/refwrap.const/type_ctor.fail.cpp
index f7a6670b431f3a56e2f61e83c55ca1c4868e9322..f02a9974d7da0bc32786c1208f82350c3d106097 100644
--- a/libcxx/test/std/utilities/function.objects/refwrap/refwrap.const/type_ctor.fail.cpp
+++ b/libcxx/test/std/utilities/function.objects/refwrap/refwrap.const/type_ctor.fail.cpp
@@ -17,7 +17,9 @@
 #include <functional>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::reference_wrapper<const int> r(3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/refwrap/refwrap.const/type_ctor.pass.cpp b/libcxx/test/std/utilities/function.objects/refwrap/refwrap.const/type_ctor.pass.cpp
index 2cbb1a010f12c46f76695f300b09267e9464eec1..a43d0fd25109f381c0bb6c1d60d8e380e13bf034 100644
--- a/libcxx/test/std/utilities/function.objects/refwrap/refwrap.const/type_ctor.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/refwrap/refwrap.const/type_ctor.pass.cpp
@@ -29,7 +29,7 @@ test(T& t)
 
 void f() {}
 
-int main()
+int main(int, char**)
 {
     void (*fp)() = f;
     test(fp);
@@ -40,4 +40,6 @@ int main()
     test(i);
     const int j = 0;
     test(j);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/refwrap/refwrap.helpers/cref_1.pass.cpp b/libcxx/test/std/utilities/function.objects/refwrap/refwrap.helpers/cref_1.pass.cpp
index b16a4b476c3dcc791f372fbaf080d02491ed4e43..d4cb421f53eb4a92f62f2ba44296842f6bcab6d2 100644
--- a/libcxx/test/std/utilities/function.objects/refwrap/refwrap.helpers/cref_1.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/refwrap/refwrap.helpers/cref_1.pass.cpp
@@ -15,9 +15,11 @@
 #include <functional>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int i = 0;
     std::reference_wrapper<const int> r = std::cref(i);
     assert(&r.get() == &i);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/refwrap/refwrap.helpers/cref_2.pass.cpp b/libcxx/test/std/utilities/function.objects/refwrap/refwrap.helpers/cref_2.pass.cpp
index 3023f8da2a3b59b61a43804b6deea1031d24a22e..093b7e230fd49a263f501c4efefbe6f9e661eaf6 100644
--- a/libcxx/test/std/utilities/function.objects/refwrap/refwrap.helpers/cref_2.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/refwrap/refwrap.helpers/cref_2.pass.cpp
@@ -15,10 +15,12 @@
 #include <functional>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const int i = 0;
     std::reference_wrapper<const int> r1 = std::cref(i);
     std::reference_wrapper<const int> r2 = std::cref(r1);
     assert(&r2.get() == &i);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/refwrap/refwrap.helpers/ref_1.fail.cpp b/libcxx/test/std/utilities/function.objects/refwrap/refwrap.helpers/ref_1.fail.cpp
index 9e283d1bfaf14b8bc6b88e663bf381317f37cd22..c07028d21ddda020c4d2eabdf3cdb4d352d14863 100644
--- a/libcxx/test/std/utilities/function.objects/refwrap/refwrap.helpers/ref_1.fail.cpp
+++ b/libcxx/test/std/utilities/function.objects/refwrap/refwrap.helpers/ref_1.fail.cpp
@@ -22,7 +22,9 @@ struct A {};
 
 const A source() {return A();}
 
-int main()
+int main(int, char**)
 {
     std::reference_wrapper<const A> r = std::ref(source());
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/refwrap/refwrap.helpers/ref_1.pass.cpp b/libcxx/test/std/utilities/function.objects/refwrap/refwrap.helpers/ref_1.pass.cpp
index a8af5aa4cfe3e3722f61c97c1624c8c266693d22..f64d8ad8caeba2c2a4821573f2c04e98c659332a 100644
--- a/libcxx/test/std/utilities/function.objects/refwrap/refwrap.helpers/ref_1.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/refwrap/refwrap.helpers/ref_1.pass.cpp
@@ -15,9 +15,11 @@
 #include <functional>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int i = 0;
     std::reference_wrapper<int> r = std::ref(i);
     assert(&r.get() == &i);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/refwrap/refwrap.helpers/ref_2.pass.cpp b/libcxx/test/std/utilities/function.objects/refwrap/refwrap.helpers/ref_2.pass.cpp
index fee5009a73b721b5a52bd370a10927f7c797e967..4fdaf992c64d0a15637e094f25c8b7faac11b360 100644
--- a/libcxx/test/std/utilities/function.objects/refwrap/refwrap.helpers/ref_2.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/refwrap/refwrap.helpers/ref_2.pass.cpp
@@ -22,7 +22,7 @@ bool is5 ( int i ) { return i == 5; }
 template <typename T>
 bool call_pred ( T pred ) { return pred(5); }
 
-int main()
+int main(int, char**)
 {
     {
     int i = 0;
@@ -39,4 +39,6 @@ int main()
     assert(call_pred(std::ref(cp)));
     assert(cp.count() == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/refwrap/refwrap.invoke/invoke.fail.cpp b/libcxx/test/std/utilities/function.objects/refwrap/refwrap.invoke/invoke.fail.cpp
index 6302c51b8ad96125c17d44dfbc38661a55a6ed4e..d54d5184c65be8ba46dee7607c0ffd83784e5c66 100644
--- a/libcxx/test/std/utilities/function.objects/refwrap/refwrap.invoke/invoke.fail.cpp
+++ b/libcxx/test/std/utilities/function.objects/refwrap/refwrap.invoke/invoke.fail.cpp
@@ -45,7 +45,9 @@ test_int_1()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test_int_1();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/refwrap/refwrap.invoke/invoke.pass.cpp b/libcxx/test/std/utilities/function.objects/refwrap/refwrap.invoke/invoke.pass.cpp
index 425bc6df0c82cd78a8c48684bb05446a0a401cc7..fd31041330dd33e4ee3fd6b8b636bc23270715ea 100644
--- a/libcxx/test/std/utilities/function.objects/refwrap/refwrap.invoke/invoke.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/refwrap/refwrap.invoke/invoke.pass.cpp
@@ -319,10 +319,12 @@ testint_2()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test_void_1();
     test_int_1();
     test_void_2();
     testint_2();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/refwrap/refwrap.invoke/invoke_int_0.pass.cpp b/libcxx/test/std/utilities/function.objects/refwrap/refwrap.invoke/invoke_int_0.pass.cpp
index 37d7cfca9deeab67ba4900ce4820ae486b5f627f..67cf51f33596fa46be7593e1fce7bd89778b9876 100644
--- a/libcxx/test/std/utilities/function.objects/refwrap/refwrap.invoke/invoke_int_0.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/refwrap/refwrap.invoke/invoke_int_0.pass.cpp
@@ -69,7 +69,9 @@ struct A_void_1
     }
 };
 
-int main()
+int main(int, char**)
 {
     test_int_0();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/refwrap/refwrap.invoke/invoke_void_0.pass.cpp b/libcxx/test/std/utilities/function.objects/refwrap/refwrap.invoke/invoke_void_0.pass.cpp
index 735bfd890dd30a94dcc6c35c65f6a97ef2336099..18e655313336d580d868ba2c5dce36539569205c 100644
--- a/libcxx/test/std/utilities/function.objects/refwrap/refwrap.invoke/invoke_void_0.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/refwrap/refwrap.invoke/invoke_void_0.pass.cpp
@@ -61,7 +61,9 @@ test_void_0()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test_void_0();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/refwrap/type.pass.cpp b/libcxx/test/std/utilities/function.objects/refwrap/type.pass.cpp
index ef46e15d0a043673939cc0a2bd63181612366698..d17ab8100ef0d0583e32259a90030c6f350272c4 100644
--- a/libcxx/test/std/utilities/function.objects/refwrap/type.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/refwrap/type.pass.cpp
@@ -17,7 +17,7 @@
 
 class C {};
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::reference_wrapper<C>::type,
                                                        C>::value), "");
@@ -33,4 +33,6 @@ int main()
                                                        int*(C::*)(double*)>::value), "");
     static_assert((std::is_same<std::reference_wrapper<int (C::*)(double*) const volatile>::type,
                                                        int (C::*)(double*) const volatile>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/refwrap/type_properties.pass.cpp b/libcxx/test/std/utilities/function.objects/refwrap/type_properties.pass.cpp
index 14a06a9c316d0ba572151d9768aa50f415a476c8..17eef26f07a6d794abc0b650643803a941dca737 100644
--- a/libcxx/test/std/utilities/function.objects/refwrap/type_properties.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/refwrap/type_properties.pass.cpp
@@ -52,7 +52,7 @@ void test()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test<int>();
     test<double>();
@@ -60,4 +60,6 @@ int main()
 #if TEST_STD_VER >= 11
     test<MoveOnly>();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/refwrap/unwrap_ref_decay.pass.cpp b/libcxx/test/std/utilities/function.objects/refwrap/unwrap_ref_decay.pass.cpp
index 9aaa2827997d426c312a38c1a55a15373106fae3..1987898393cd13a8baa68d9735ddcc956156ffd0 100644
--- a/libcxx/test/std/utilities/function.objects/refwrap/unwrap_ref_decay.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/refwrap/unwrap_ref_decay.pass.cpp
@@ -28,7 +28,7 @@ void check() {
 
 struct T { };
 
-int main() {
+int main(int, char**) {
   check<T,             T>();
   check<T&,            T>();
   check<T const,       T>();
@@ -54,4 +54,6 @@ int main() {
   check<std::reference_wrapper<T[3]>&,     T (&)[3]>();
   check<std::reference_wrapper<T ()>,      T (&)()>();
   check<std::reference_wrapper<T ()>&,     T (&)()>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/refwrap/unwrap_reference.pass.cpp b/libcxx/test/std/utilities/function.objects/refwrap/unwrap_reference.pass.cpp
index f6d48a51e8b498ad8593e29f51fcd0477fa765b5..209d5e2a0bc93deb4f826bf131e288e89a0cb294 100644
--- a/libcxx/test/std/utilities/function.objects/refwrap/unwrap_reference.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/refwrap/unwrap_reference.pass.cpp
@@ -39,7 +39,7 @@ void check() {
 
 struct T { };
 
-int main() {
+int main(int, char**) {
   check<T>();
   check<int>();
   check<float>();
@@ -47,4 +47,6 @@ int main() {
   check<T*>();
   check<int*>();
   check<float*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/refwrap/weak_result.pass.cpp b/libcxx/test/std/utilities/function.objects/refwrap/weak_result.pass.cpp
index 50cda11693274b6ee4537b31a1e91f6c837812e2..5a6a41fdbe0eb04e730143830371bf6e66601d23 100644
--- a/libcxx/test/std/utilities/function.objects/refwrap/weak_result.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/refwrap/weak_result.pass.cpp
@@ -68,7 +68,7 @@ public:
     static const bool value = sizeof(test<T>(0)) == 1;
 };
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::reference_wrapper<functor1>::result_type,
                                 char>::value), "");
@@ -93,4 +93,6 @@ int main()
     static_assert(has_result_type<std::reference_wrapper<functor3> >::value, "");
     static_assert(!has_result_type<std::reference_wrapper<functor4> >::value, "");
     static_assert(!has_result_type<std::reference_wrapper<C> >::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/unord.hash/enabled_hashes.pass.cpp b/libcxx/test/std/utilities/function.objects/unord.hash/enabled_hashes.pass.cpp
index 90ab8e1bb79d2bb144f24b5bf27ec8f6ede1897f..8f6c3e14e2cf91a2df3bd8013b1d4c72d326c903 100644
--- a/libcxx/test/std/utilities/function.objects/unord.hash/enabled_hashes.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/unord.hash/enabled_hashes.pass.cpp
@@ -17,6 +17,8 @@
 
 #include "poisoned_hash_helper.hpp"
 
-int main() {
+int main(int, char**) {
   test_library_hash_specializations_available();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/unord.hash/enum.fail.cpp b/libcxx/test/std/utilities/function.objects/unord.hash/enum.fail.cpp
index b824b51ea799154f7b88be2c7dbdd60a9741f7ac..2e36b4c55318a3fdb62acfb153f8f4cac33e074a 100644
--- a/libcxx/test/std/utilities/function.objects/unord.hash/enum.fail.cpp
+++ b/libcxx/test/std/utilities/function.objects/unord.hash/enum.fail.cpp
@@ -16,8 +16,10 @@
 
 struct X {};
 
-int main()
+int main(int, char**)
 {
     X x;
     size_t h = std::hash<X>{} ( x );
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/unord.hash/enum.pass.cpp b/libcxx/test/std/utilities/function.objects/unord.hash/enum.pass.cpp
index 96c667febcb8e8819b7c1659561992620c20452d..e172bc2f346942890ec06b2b0a17216caae5b663 100644
--- a/libcxx/test/std/utilities/function.objects/unord.hash/enum.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/unord.hash/enum.pass.cpp
@@ -49,7 +49,7 @@ test()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<Cardinals>();
 
@@ -59,4 +59,6 @@ int main()
     test<EightBitColors>();
 
     test<Fruits>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/unord.hash/floating.pass.cpp b/libcxx/test/std/utilities/function.objects/unord.hash/floating.pass.cpp
index 1ab1643413a9fe9271840bc208d94b32c1c00917..31b1b2d07e40738aec8c7542fdbf27b7f38b8aa3 100644
--- a/libcxx/test/std/utilities/function.objects/unord.hash/floating.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/unord.hash/floating.pass.cpp
@@ -64,9 +64,11 @@ test()
     assert(pinf != ninf);
 }
 
-int main()
+int main(int, char**)
 {
     test<float>();
     test<double>();
     test<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/unord.hash/integral.pass.cpp b/libcxx/test/std/utilities/function.objects/unord.hash/integral.pass.cpp
index 761c76dc141e44f3cb3f9491daa0b728d407ae85..dbd44a88207b3d4c2eaf66f8cd3f30a28ce0c2c2 100644
--- a/libcxx/test/std/utilities/function.objects/unord.hash/integral.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/unord.hash/integral.pass.cpp
@@ -46,7 +46,7 @@ test()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<bool>();
     test<char>();
@@ -108,4 +108,6 @@ int main()
     test<__int128_t>();
     test<__uint128_t>();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/unord.hash/non_enum.pass.cpp b/libcxx/test/std/utilities/function.objects/unord.hash/non_enum.pass.cpp
index 6efcebc4ebeae794dafe70592300700de8d413a9..c47f8fa76a4b3f397a7ef64ecd7fc16e1fefaa85 100644
--- a/libcxx/test/std/utilities/function.objects/unord.hash/non_enum.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/unord.hash/non_enum.pass.cpp
@@ -22,7 +22,7 @@
 
 struct X {};
 
-int main()
+int main(int, char**)
 {
     using H = std::hash<X>;
     static_assert(!std::is_default_constructible<H>::value, "");
@@ -34,4 +34,6 @@ int main()
     static_assert(!std::is_invocable<H, X&>::value, "");
     static_assert(!std::is_invocable<H, X const&>::value, "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/function.objects/unord.hash/pointer.pass.cpp b/libcxx/test/std/utilities/function.objects/unord.hash/pointer.pass.cpp
index cbf2c736eabba584c399135a3dc60416717320b6..17dfdce2d4a855a9133cb0facfe12d4471845421 100644
--- a/libcxx/test/std/utilities/function.objects/unord.hash/pointer.pass.cpp
+++ b/libcxx/test/std/utilities/function.objects/unord.hash/pointer.pass.cpp
@@ -52,8 +52,10 @@ void test_nullptr()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test<int*>();
     test_nullptr();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/intseq/intseq.general/integer_seq.pass.cpp b/libcxx/test/std/utilities/intseq/intseq.general/integer_seq.pass.cpp
index 8da459ff81d6ea014923c6e4ea45bcecab51fcb9..90b09132d9e4c9482ddaed0b39bb5329c58d1091 100644
--- a/libcxx/test/std/utilities/intseq/intseq.general/integer_seq.pass.cpp
+++ b/libcxx/test/std/utilities/intseq/intseq.general/integer_seq.pass.cpp
@@ -21,7 +21,7 @@ auto extract ( const AtContainer &t, const std::integer_sequence<T, I...> )
 -> decltype ( std::make_tuple ( std::get<I>(t)... ))
 {     return  std::make_tuple ( std::get<I>(t)... ); }
 
-int main()
+int main(int, char**)
 {
 //  Make a couple of sequences
     using int3    = std::make_integer_sequence<int, 3>;     // generates int:    0,1,2
@@ -76,4 +76,6 @@ int main()
     auto tsizemix = extract ( tup, sizemix ());
     static_assert ( std::tuple_size<decltype(tsizemix)>::value == sizemix::size (), "tsizemix size wrong");
     assert ( tsizemix == std::make_tuple ( 11, 11, 12, 13, 15 ));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/intseq/intseq.intseq/integer_seq.fail.cpp b/libcxx/test/std/utilities/intseq/intseq.intseq/integer_seq.fail.cpp
index 44ffb017876277da4a11605fc374c28a6e9efa2a..248b346e33a0d139644106002f8a93d540d117a3 100644
--- a/libcxx/test/std/utilities/intseq/intseq.intseq/integer_seq.fail.cpp
+++ b/libcxx/test/std/utilities/intseq/intseq.intseq/integer_seq.fail.cpp
@@ -23,7 +23,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 #if TEST_STD_VER > 11
 
@@ -36,4 +36,6 @@ int main()
 X
 
 #endif  // TEST_STD_VER > 11
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/intseq/intseq.intseq/integer_seq.pass.cpp b/libcxx/test/std/utilities/intseq/intseq.intseq/integer_seq.pass.cpp
index 653d2988a7cc29788b77d1a8deb7ba6d7a8b426f..a8e14c9a9cdd88777d547162aa933bd942038777 100644
--- a/libcxx/test/std/utilities/intseq/intseq.intseq/integer_seq.pass.cpp
+++ b/libcxx/test/std/utilities/intseq/intseq.intseq/integer_seq.pass.cpp
@@ -22,7 +22,7 @@
 #include <cstddef>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
 //  Make a few of sequences
     using int3    = std::integer_sequence<int, 3, 2, 1>;
@@ -42,4 +42,6 @@ int main()
 
     static_assert ( std::is_same<bool0::value_type, bool>::value, "bool0 type wrong" );
     static_assert ( bool0::size() == 0, "bool0 size wrong" );
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/intseq/intseq.make/make_integer_seq.fail.cpp b/libcxx/test/std/utilities/intseq/intseq.make/make_integer_seq.fail.cpp
index 2f2a6608b2c87f67838d592c3040b40d6f3dae49..ec2e8cc7c2c391c5d287113f28870c1c2e545c5d 100644
--- a/libcxx/test/std/utilities/intseq/intseq.make/make_integer_seq.fail.cpp
+++ b/libcxx/test/std/utilities/intseq/intseq.make/make_integer_seq.fail.cpp
@@ -22,7 +22,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
   typedef std::make_integer_sequence<int, -3> MakeSeqT;
 
@@ -33,4 +33,6 @@ int main()
 #else
     MakeSeqT i; // expected-error@utility:* {{static_assert failed "std::make_integer_sequence must have a non-negative sequence length"}}
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/intseq/intseq.make/make_integer_seq.pass.cpp b/libcxx/test/std/utilities/intseq/intseq.make/make_integer_seq.pass.cpp
index 3c522c73bf986095696043d0b3f3e52f13312b24..50b49dd725e408de797d241324da10b2ed98aff6 100644
--- a/libcxx/test/std/utilities/intseq/intseq.make/make_integer_seq.pass.cpp
+++ b/libcxx/test/std/utilities/intseq/intseq.make/make_integer_seq.pass.cpp
@@ -17,7 +17,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     static_assert(std::is_same<std::make_integer_sequence<int, 0>, std::integer_sequence<int>>::value, "");
     static_assert(std::is_same<std::make_integer_sequence<int, 1>, std::integer_sequence<int, 0>>::value, "");
@@ -28,4 +28,6 @@ int main()
     static_assert(std::is_same<std::make_integer_sequence<unsigned long long, 1>, std::integer_sequence<unsigned long long, 0>>::value, "");
     static_assert(std::is_same<std::make_integer_sequence<unsigned long long, 2>, std::integer_sequence<unsigned long long, 0, 1>>::value, "");
     static_assert(std::is_same<std::make_integer_sequence<unsigned long long, 3>, std::integer_sequence<unsigned long long, 0, 1, 2>>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/intseq/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/intseq/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/intseq/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/intseq/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/allocator.tag/allocator_arg.pass.cpp b/libcxx/test/std/utilities/memory/allocator.tag/allocator_arg.pass.cpp
index b095dbfaf1660aaee1afb020e9d2491027630d15..1a58726a854629d6afdb571761c44d3b5629fb26 100644
--- a/libcxx/test/std/utilities/memory/allocator.tag/allocator_arg.pass.cpp
+++ b/libcxx/test/std/utilities/memory/allocator.tag/allocator_arg.pass.cpp
@@ -15,7 +15,9 @@
 
 void test(std::allocator_arg_t) {}
 
-int main()
+int main(int, char**)
 {
     test(std::allocator_arg);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/allocate.fail.cpp b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/allocate.fail.cpp
index 60f267fa5e399c71e26a8581650844260d51191c..47cfbb0494b563193f1ef944f5956d4eeb5d0e31 100644
--- a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/allocate.fail.cpp
+++ b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/allocate.fail.cpp
@@ -42,9 +42,11 @@ struct A
     }
 };
 
-int main()
+int main(int, char**)
 {
     A<int> a;
     std::allocator_traits<A<int> >::allocate(a, 10);          // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
     std::allocator_traits<A<int> >::allocate(a, 10, nullptr); // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/allocate.pass.cpp b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/allocate.pass.cpp
index a892be03d9dd44d0d6f4652194650e90172adc54..0ac2f266e815598075f6cd8eebb9a6aa7f237c21 100644
--- a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/allocate.pass.cpp
+++ b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/allocate.pass.cpp
@@ -33,7 +33,7 @@ struct A
     }
 };
 
-int main()
+int main(int, char**)
 {
   {
     A<int> a;
@@ -45,4 +45,6 @@ int main()
     Alloc a;
     assert(std::allocator_traits<Alloc >::allocate(a, 10) == reinterpret_cast<VT*>(static_cast<std::uintptr_t>(0xDEADBEEF)));
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/allocate_hint.pass.cpp b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/allocate_hint.pass.cpp
index 9d4631740b0508f6c71b0dc5ae5a6cedb27ce732..e95247163988ce3235289888ed031f26a8f8af89 100644
--- a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/allocate_hint.pass.cpp
+++ b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/allocate_hint.pass.cpp
@@ -53,7 +53,7 @@ struct B
 };
 
 
-int main()
+int main(int, char**)
 {
 #if TEST_STD_VER >= 11
   {
@@ -77,4 +77,6 @@ int main()
     Alloc b;
     assert(std::allocator_traits<Alloc >::allocate(b, 11, nullptr) == reinterpret_cast<VT*>(static_cast<std::uintptr_t>(0xFEADBEEF)));
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/construct.pass.cpp b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/construct.pass.cpp
index 252d99a7a7499a552c2a3253436674c9d3c62cc3..67a2e8f4ac8b2e9cc203ee65e8e5dededa7f7e9f 100644
--- a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/construct.pass.cpp
+++ b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/construct.pass.cpp
@@ -81,7 +81,7 @@ struct A2
 
 int A2::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         A0::count = 0;
@@ -149,4 +149,6 @@ int main()
         assert(b_construct == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/deallocate.pass.cpp b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/deallocate.pass.cpp
index 94f10b64dba913d2913e9e6d55517b201266b548..c738416e01dcebe8832d761a51cb3c2bcadf3a5d 100644
--- a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/deallocate.pass.cpp
+++ b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/deallocate.pass.cpp
@@ -36,7 +36,7 @@ struct A
     }
 };
 
-int main()
+int main(int, char**)
 {
   {
     A<int> a;
@@ -51,4 +51,6 @@ int main()
     std::allocator_traits<Alloc >::deallocate(a, reinterpret_cast<VT*>(static_cast<std::uintptr_t>(0xDEADBEEF)), 10);
     assert(called == 1);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/destroy.pass.cpp b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/destroy.pass.cpp
index 677c647a27dc61f59b3abc5a12482b5e31623a09..70890d8512fd2a31226b5244a4d4acab32f6495f 100644
--- a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/destroy.pass.cpp
+++ b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/destroy.pass.cpp
@@ -54,7 +54,7 @@ struct A0
 
 int A0::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         A0::count = 0;
@@ -86,4 +86,6 @@ int main()
         assert(b_destroy == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/max_size.pass.cpp b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/max_size.pass.cpp
index a51ec6e95ac132f11faeb30055cee6ade5e132f5..b758c9add8c0ed758fa634db3f561ccfe5f37efb 100644
--- a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/max_size.pass.cpp
+++ b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/max_size.pass.cpp
@@ -42,7 +42,7 @@ struct B
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         B<int> b;
@@ -74,4 +74,6 @@ int main()
         static_assert(noexcept(std::allocator_traits<std::allocator<int>>::max_size(a)) == true, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/select_on_container_copy_construction.pass.cpp b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/select_on_container_copy_construction.pass.cpp
index 9594531dad9ab3d1484db2dfb42af0877dce9468..be837670dd3f317d1bfc11e9848513f68f2488f0 100644
--- a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/select_on_container_copy_construction.pass.cpp
+++ b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.members/select_on_container_copy_construction.pass.cpp
@@ -47,7 +47,7 @@ struct B
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
         A<int> a;
@@ -73,4 +73,6 @@ int main()
         assert(std::allocator_traits<B<int> >::select_on_container_copy_construction(b).id == 100);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/const_pointer.pass.cpp b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/const_pointer.pass.cpp
index f153d95b4aa448d0051bd9d1efbcf1892154f782..756958b584f3f92c729aef892a31b9ed3c5ee6e4 100644
--- a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/const_pointer.pass.cpp
+++ b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/const_pointer.pass.cpp
@@ -55,7 +55,7 @@ private:
   typedef void const_pointer;
 };
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::allocator_traits<A<char> >::const_pointer, Ptr<const char> >::value), "");
     static_assert((std::is_same<std::allocator_traits<B<char> >::const_pointer, const char*>::value), "");
@@ -63,4 +63,6 @@ int main()
 #if TEST_STD_VER >= 11
     static_assert((std::is_same<std::allocator_traits<D<char> >::const_pointer, const char*>::value), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/const_void_pointer.pass.cpp b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/const_void_pointer.pass.cpp
index 3acedde65443fa5fcd3ffd4073fd63b277405ad2..4fcc2fb7c15ec630b8d00cbb57e6d23e44db0abf 100644
--- a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/const_void_pointer.pass.cpp
+++ b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/const_void_pointer.pass.cpp
@@ -57,7 +57,7 @@ private:
     typedef int const_void_pointer;
 };
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::allocator_traits<A<char> >::const_void_pointer, Ptr<const void> >::value), "");
     static_assert((std::is_same<std::allocator_traits<B<char> >::const_void_pointer, const void*>::value), "");
@@ -65,4 +65,6 @@ int main()
 #if TEST_STD_VER >= 11
     static_assert((std::is_same<std::allocator_traits<D<char> >::const_void_pointer, const void*>::value), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/difference_type.pass.cpp b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/difference_type.pass.cpp
index b0ee16350839ad905b591e516bfee7b371823a63..35721f1cbba9d2c116e44c97e048447edfe4b864 100644
--- a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/difference_type.pass.cpp
+++ b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/difference_type.pass.cpp
@@ -66,7 +66,7 @@ struct pointer_traits<C<char>::pointer>
 
 }
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::allocator_traits<A<char> >::difference_type, short>::value), "");
     static_assert((std::is_same<std::allocator_traits<B<char> >::difference_type, std::ptrdiff_t>::value), "");
@@ -74,4 +74,6 @@ int main()
 #if TEST_STD_VER >= 11
     static_assert((std::is_same<std::allocator_traits<D<char> >::difference_type, std::ptrdiff_t>::value), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/is_always_equal.pass.cpp b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/is_always_equal.pass.cpp
index fae61849331a88661943f7a716024f967292d023..42b0fbab19ccd537dadfd25496e087995fdea3bf 100644
--- a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/is_always_equal.pass.cpp
+++ b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/is_always_equal.pass.cpp
@@ -39,7 +39,7 @@ struct C
     int not_empty_;  // some random member variable
 };
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::allocator_traits<A<char> >::is_always_equal, std::true_type>::value), "");
     static_assert((std::is_same<std::allocator_traits<B<char> >::is_always_equal, std::true_type>::value), "");
@@ -48,4 +48,6 @@ int main()
     static_assert((std::is_same<std::allocator_traits<A<const char> >::is_always_equal, std::true_type>::value), "");
     static_assert((std::is_same<std::allocator_traits<B<const char> >::is_always_equal, std::true_type>::value), "");
     static_assert((std::is_same<std::allocator_traits<C<const char> >::is_always_equal, std::false_type>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/pointer.pass.cpp b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/pointer.pass.cpp
index 60f3d257afd976e5c19362a6da98337ab2890609..58b306660a8630b4feb7caa1c48c55d7d2a0ddc9 100644
--- a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/pointer.pass.cpp
+++ b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/pointer.pass.cpp
@@ -43,11 +43,13 @@ private:
     typedef void pointer;
 };
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::allocator_traits<A<char> >::pointer, Ptr<char> >::value), "");
     static_assert((std::is_same<std::allocator_traits<B<char> >::pointer, char*>::value), "");
 #if TEST_STD_VER >= 11
     static_assert((std::is_same<std::allocator_traits<C<char> >::pointer, char*>::value), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/propagate_on_container_copy_assignment.pass.cpp b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/propagate_on_container_copy_assignment.pass.cpp
index c8451b2a975b929ec3cac3dbea731f8fe4a7a501..b049159e2d1b9978e4d2fd7f82c9b9bc8ce27cbb 100644
--- a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/propagate_on_container_copy_assignment.pass.cpp
+++ b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/propagate_on_container_copy_assignment.pass.cpp
@@ -43,11 +43,13 @@ private:
     typedef std::true_type propagate_on_container_copy_assignment;
 };
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::allocator_traits<A<char> >::propagate_on_container_copy_assignment, std::true_type>::value), "");
     static_assert((std::is_same<std::allocator_traits<B<char> >::propagate_on_container_copy_assignment, std::false_type>::value), "");
 #if TEST_STD_VER >= 11
     static_assert((std::is_same<std::allocator_traits<C<char> >::propagate_on_container_copy_assignment, std::false_type>::value), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/propagate_on_container_move_assignment.pass.cpp b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/propagate_on_container_move_assignment.pass.cpp
index 7c58ac8811ba50839cc7780b71f4b89ade31271d..602ba96d5c114d1c5a751e15676e51019643dac6 100644
--- a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/propagate_on_container_move_assignment.pass.cpp
+++ b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/propagate_on_container_move_assignment.pass.cpp
@@ -44,11 +44,13 @@ private:
 };
 
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::allocator_traits<A<char> >::propagate_on_container_move_assignment, std::true_type>::value), "");
     static_assert((std::is_same<std::allocator_traits<B<char> >::propagate_on_container_move_assignment, std::false_type>::value), "");
 #if TEST_STD_VER >= 11
     static_assert((std::is_same<std::allocator_traits<C<char> >::propagate_on_container_move_assignment, std::false_type>::value), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/propagate_on_container_swap.pass.cpp b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/propagate_on_container_swap.pass.cpp
index 7a6bcd460a6e1a5f950037a0f0662ddef285d93f..5ae53015fa34a151841b4d9a008ea56c471d91d8 100644
--- a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/propagate_on_container_swap.pass.cpp
+++ b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/propagate_on_container_swap.pass.cpp
@@ -42,11 +42,13 @@ private:
     typedef std::true_type propagate_on_container_swap;
 };
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::allocator_traits<A<char> >::propagate_on_container_swap, std::true_type>::value), "");
     static_assert((std::is_same<std::allocator_traits<B<char> >::propagate_on_container_swap, std::false_type>::value), "");
  #if TEST_STD_VER >= 11
     static_assert((std::is_same<std::allocator_traits<C<char> >::propagate_on_container_swap, std::false_type>::value), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/rebind_alloc.pass.cpp b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/rebind_alloc.pass.cpp
index eaadeb17048db75887972ef620036df38a559cb1..d0d8476a89a9e393c96a0fc179baf4f8223383cc 100644
--- a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/rebind_alloc.pass.cpp
+++ b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/rebind_alloc.pass.cpp
@@ -80,7 +80,7 @@ struct G {
     };
 };
 
-int main()
+int main(int, char**)
 {
 #if TEST_STD_VER >= 11
     static_assert((std::is_same<std::allocator_traits<A<char> >::rebind_alloc<double>, ReboundA<double> >::value), "");
@@ -97,4 +97,6 @@ int main()
     static_assert((std::is_same<std::allocator_traits<D<int, char> >::rebind_alloc<double>::other, D<double, char> >::value), "");
     static_assert((std::is_same<std::allocator_traits<E<char> >::rebind_alloc<double>::other, E<double> >::value), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/size_type.pass.cpp b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/size_type.pass.cpp
index 42b29a39c7b3379dcd76e5d78509d66929670b0e..cd74671390e7eede9d87bb6dad17e4e2eb416354 100644
--- a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/size_type.pass.cpp
+++ b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/size_type.pass.cpp
@@ -62,7 +62,7 @@ struct pointer_traits<C<char>::pointer>
 
 }
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::allocator_traits<A<char> >::size_type, unsigned short>::value), "");
     static_assert((std::is_same<std::allocator_traits<B<char> >::size_type,
@@ -72,4 +72,6 @@ int main()
 #if TEST_STD_VER >= 11
     static_assert((std::is_same<std::allocator_traits<D<char> >::size_type, unsigned short>::value), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/void_pointer.pass.cpp b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/void_pointer.pass.cpp
index 687d892f0cfed5b849e20f4b110d67308ff4ed0a..55954dc7091ab78cb0f59d07d07646f216b8d08b 100644
--- a/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/void_pointer.pass.cpp
+++ b/libcxx/test/std/utilities/memory/allocator.traits/allocator.traits.types/void_pointer.pass.cpp
@@ -56,7 +56,7 @@ private:
     typedef void void_pointer;
 };
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::allocator_traits<A<char> >::void_pointer, Ptr<void> >::value), "");
     static_assert((std::is_same<std::allocator_traits<B<char> >::void_pointer, void*>::value), "");
@@ -64,4 +64,6 @@ int main()
 #if TEST_STD_VER >= 11
     static_assert((std::is_same<std::allocator_traits<D<char> >::void_pointer, void*>::value), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/allocator.traits/allocator_type.pass.cpp b/libcxx/test/std/utilities/memory/allocator.traits/allocator_type.pass.cpp
index d5977f0a28ffdfe51d83f410e5cb6658d505525e..840ad820e1fe14f0bf3a10d0901a9d0aa1e2d8eb 100644
--- a/libcxx/test/std/utilities/memory/allocator.traits/allocator_type.pass.cpp
+++ b/libcxx/test/std/utilities/memory/allocator.traits/allocator_type.pass.cpp
@@ -24,7 +24,9 @@ struct A
     typedef T value_type;
 };
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::allocator_traits<A<char> >::allocator_type, A<char> >::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/allocator.traits/rebind_traits.pass.cpp b/libcxx/test/std/utilities/memory/allocator.traits/rebind_traits.pass.cpp
index 475ab04b8399440ee221d3df99803694602ed451..01aac9445c83854c8e693bcfa97ca64ddd0a0c2d 100644
--- a/libcxx/test/std/utilities/memory/allocator.traits/rebind_traits.pass.cpp
+++ b/libcxx/test/std/utilities/memory/allocator.traits/rebind_traits.pass.cpp
@@ -62,7 +62,7 @@ struct E
     template <class U> struct rebind {typedef ReboundA<U> otter;};
 };
 
-int main()
+int main(int, char**)
 {
 #if TEST_STD_VER >= 11
     static_assert((std::is_same<std::allocator_traits<A<char> >::rebind_traits<double>, std::allocator_traits<ReboundA<double> > >::value), "");
@@ -77,4 +77,6 @@ int main()
     static_assert((std::is_same<std::allocator_traits<D<int, char> >::rebind_traits<double>::other, std::allocator_traits<D<double, char> > >::value), "");
     static_assert((std::is_same<std::allocator_traits<E<char> >::rebind_traits<double>::other, std::allocator_traits<E<double> > >::value), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/allocator.traits/value_type.pass.cpp b/libcxx/test/std/utilities/memory/allocator.traits/value_type.pass.cpp
index dec3a41e374a34f6a12fc7a8d4e794f52f968240..047d40d5c89a143e977302e032ef5e099be309b8 100644
--- a/libcxx/test/std/utilities/memory/allocator.traits/value_type.pass.cpp
+++ b/libcxx/test/std/utilities/memory/allocator.traits/value_type.pass.cpp
@@ -24,7 +24,9 @@ struct A
     typedef T value_type;
 };
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::allocator_traits<A<char> >::value_type, char>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/allocator.uses/allocator.uses.construction/tested_elsewhere.pass.cpp b/libcxx/test/std/utilities/memory/allocator.uses/allocator.uses.construction/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/memory/allocator.uses/allocator.uses.construction/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/utilities/memory/allocator.uses/allocator.uses.construction/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/allocator.uses/allocator.uses.trait/uses_allocator.pass.cpp b/libcxx/test/std/utilities/memory/allocator.uses/allocator.uses.trait/uses_allocator.pass.cpp
index 5b7f710eab05d57d786659fa0255caa1ee4ac4f8..d9d4fc3d837c85e0e5500b66a435377edfd93a96 100644
--- a/libcxx/test/std/utilities/memory/allocator.uses/allocator.uses.trait/uses_allocator.pass.cpp
+++ b/libcxx/test/std/utilities/memory/allocator.uses/allocator.uses.trait/uses_allocator.pass.cpp
@@ -47,7 +47,7 @@ test()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test<false, int, std::allocator<int> >();
     test<true, std::vector<int>, std::allocator<int> >();
@@ -71,4 +71,6 @@ int main()
 // #if TEST_STD_VER >= 11
 //     static_assert((!std::uses_allocator<E, int>::value), "");
 // #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/allocator.uses/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/memory/allocator.uses/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/memory/allocator.uses/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/memory/allocator.uses/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/c.malloc/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/memory/c.malloc/nothing_to_do.pass.cpp
index a8d90b1ce6f495982945697ca67450791a7a89f7..7e6c6780070ac678fa9e52143d3a8be53354ecdf 100644
--- a/libcxx/test/std/utilities/memory/c.malloc/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/memory/c.malloc/nothing_to_do.pass.cpp
@@ -8,6 +8,8 @@
 
 // <cstdlib> and <cstring> are already tested elsewhere
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/default.allocator/allocator.ctor.pass.cpp b/libcxx/test/std/utilities/memory/default.allocator/allocator.ctor.pass.cpp
index 7aa2dbfeb037349c9d9036c0fd209782d515f157..57946be085a1744babc39904686f03de84be4e5f 100644
--- a/libcxx/test/std/utilities/memory/default.allocator/allocator.ctor.pass.cpp
+++ b/libcxx/test/std/utilities/memory/default.allocator/allocator.ctor.pass.cpp
@@ -25,7 +25,7 @@
 #include "test_macros.h"
 
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::allocator<char> AC;
@@ -46,4 +46,6 @@ int main()
     (void) a3;
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/default.allocator/allocator.globals/eq.pass.cpp b/libcxx/test/std/utilities/memory/default.allocator/allocator.globals/eq.pass.cpp
index b38daf8e91263af493044cc778ec62b024aa786c..63412bce1f4b5888fd5416a81061a6756fee9fb2 100644
--- a/libcxx/test/std/utilities/memory/default.allocator/allocator.globals/eq.pass.cpp
+++ b/libcxx/test/std/utilities/memory/default.allocator/allocator.globals/eq.pass.cpp
@@ -21,10 +21,12 @@
 #include <memory>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::allocator<int> a1;
     std::allocator<int> a2;
     assert(a1 == a2);
     assert(!(a1 != a2));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/default.allocator/allocator.members/address.pass.cpp b/libcxx/test/std/utilities/memory/default.allocator/allocator.members/address.pass.cpp
index bb1bb4f11ee3763b64886ba2c1b618e6b5d9c72b..c4ff55d0eab2943050be6a31780057d840d666f2 100644
--- a/libcxx/test/std/utilities/memory/default.allocator/allocator.members/address.pass.cpp
+++ b/libcxx/test/std/utilities/memory/default.allocator/allocator.members/address.pass.cpp
@@ -31,8 +31,10 @@ struct A
     void operator&() const {}
 };
 
-int main()
+int main(int, char**)
 {
     test_address<int>();
     test_address<A>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/default.allocator/allocator.members/allocate.fail.cpp b/libcxx/test/std/utilities/memory/default.allocator/allocator.members/allocate.fail.cpp
index df4124f51ed22b7a8a2b03478affd11a24139b5b..889804f3b71a14743cc198eedc70aea750dcc105 100644
--- a/libcxx/test/std/utilities/memory/default.allocator/allocator.members/allocate.fail.cpp
+++ b/libcxx/test/std/utilities/memory/default.allocator/allocator.members/allocate.fail.cpp
@@ -19,9 +19,11 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     std::allocator<int> a;
     a.allocate(3);          // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
     a.allocate(3, nullptr); // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/default.allocator/allocator.members/allocate.pass.cpp b/libcxx/test/std/utilities/memory/default.allocator/allocator.members/allocate.pass.cpp
index 14e5a8a3c79dc8c7e2e8c9af43ad600e4d49804f..8392cbdb7099fa52a856e41a34d4945573abea78 100644
--- a/libcxx/test/std/utilities/memory/default.allocator/allocator.members/allocate.pass.cpp
+++ b/libcxx/test/std/utilities/memory/default.allocator/allocator.members/allocate.pass.cpp
@@ -99,7 +99,7 @@ void test_aligned() {
   }
 }
 
-int main() {
+int main(int, char**) {
     test_aligned<1>();
     test_aligned<2>();
     test_aligned<4>();
@@ -108,4 +108,6 @@ int main() {
     test_aligned<MaxAligned>();
     test_aligned<OverAligned>();
     test_aligned<OverAligned * 2>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/default.allocator/allocator.members/allocate.size.pass.cpp b/libcxx/test/std/utilities/memory/default.allocator/allocator.members/allocate.size.pass.cpp
index 09a9bd912d0ed4426d8e1e1b9553e67f827b62cf..685e02ef393698e8ffe95292036088116828164a 100644
--- a/libcxx/test/std/utilities/memory/default.allocator/allocator.members/allocate.size.pass.cpp
+++ b/libcxx/test/std/utilities/memory/default.allocator/allocator.members/allocate.size.pass.cpp
@@ -39,8 +39,10 @@ void test()
     test_max<T> ((size_t) -1);                     // way too large
 }
 
-int main()
+int main(int, char**)
 {
     test<double>();
     LIBCPP_ONLY(test<const double>());
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/default.allocator/allocator.members/construct.pass.cpp b/libcxx/test/std/utilities/memory/default.allocator/allocator.members/construct.pass.cpp
index 322881b1536af27887d124b241b84a1d5c1881ab..96954e04b087343182278cdbbd0b92f13ac81d32 100644
--- a/libcxx/test/std/utilities/memory/default.allocator/allocator.members/construct.pass.cpp
+++ b/libcxx/test/std/utilities/memory/default.allocator/allocator.members/construct.pass.cpp
@@ -53,7 +53,7 @@ public:
 };
 #endif // TEST_STD_VER >= 11
 
-int main()
+int main(int, char**)
 {
     {
     std::allocator<A> a;
@@ -139,4 +139,6 @@ int main()
     assert(move_only_constructed == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/default.allocator/allocator.members/max_size.pass.cpp b/libcxx/test/std/utilities/memory/default.allocator/allocator.members/max_size.pass.cpp
index 50076ce02f42c7e8b5dfc547edda9f73b742fb21..c2094bc044a5eb34b431215fce31c53f40125ce0 100644
--- a/libcxx/test/std/utilities/memory/default.allocator/allocator.members/max_size.pass.cpp
+++ b/libcxx/test/std/utilities/memory/default.allocator/allocator.members/max_size.pass.cpp
@@ -18,9 +18,11 @@
 
 int new_called = 0;
 
-int main()
+int main(int, char**)
 {
     const std::allocator<int> a;
     std::size_t M = a.max_size();
     assert(M > 0xFFFF && M <= (std::numeric_limits<std::size_t>::max() / sizeof(int)));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/default.allocator/allocator_pointers.pass.cpp b/libcxx/test/std/utilities/memory/default.allocator/allocator_pointers.pass.cpp
index 375b96f831b2bec9882643e5ee4c1d13f00ad089..bc89c62a84713fe2c1abaf547cbba48a70c08a8c 100644
--- a/libcxx/test/std/utilities/memory/default.allocator/allocator_pointers.pass.cpp
+++ b/libcxx/test/std/utilities/memory/default.allocator/allocator_pointers.pass.cpp
@@ -108,7 +108,7 @@ void test_void_pointer()
 
 struct Foo { int x; };
 
-int main()
+int main(int, char**)
 {
     test_pointer<std::allocator<char>> ();
     test_pointer<std::allocator<int>> ();
@@ -117,7 +117,9 @@ int main()
     test_void_pointer<std::allocator<char>> ();
     test_void_pointer<std::allocator<int>> ();
     test_void_pointer<std::allocator<Foo>> ();
+
+  return 0;
 }
 #else
-int main() {}
+int main(int, char**) { return 0; }
 #endif
diff --git a/libcxx/test/std/utilities/memory/default.allocator/allocator_types.pass.cpp b/libcxx/test/std/utilities/memory/default.allocator/allocator_types.pass.cpp
index 9cd5815645ddc9ad9e332554b6c0700fe092c35c..0bff67efbd9cd049871ebe6c28f39fc89170d86a 100644
--- a/libcxx/test/std/utilities/memory/default.allocator/allocator_types.pass.cpp
+++ b/libcxx/test/std/utilities/memory/default.allocator/allocator_types.pass.cpp
@@ -33,7 +33,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::allocator<char>::size_type, std::size_t>::value), "");
     static_assert((std::is_same<std::allocator<char>::difference_type, std::ptrdiff_t>::value), "");
@@ -53,4 +53,6 @@ int main()
     a2 = a;
     std::allocator<int> a3 = a2;
     ((void)a3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/default.allocator/allocator_void.pass.cpp b/libcxx/test/std/utilities/memory/default.allocator/allocator_void.pass.cpp
index 1f13c8be6ca926e56c1c18cd35b2b9c447030ecb..528902d2112d9402bcbdf98cb557293ebc0f5e47 100644
--- a/libcxx/test/std/utilities/memory/default.allocator/allocator_void.pass.cpp
+++ b/libcxx/test/std/utilities/memory/default.allocator/allocator_void.pass.cpp
@@ -22,7 +22,7 @@
 #include <memory>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::allocator<void>::pointer, void*>::value), "");
     static_assert((std::is_same<std::allocator<void>::const_pointer, const void*>::value), "");
@@ -32,4 +32,6 @@ int main()
     std::allocator<void> a;
     std::allocator<void> a2 = a;
     a2 = a;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/pointer.conversion/to_address.pass.cpp b/libcxx/test/std/utilities/memory/pointer.conversion/to_address.pass.cpp
index 0fd45fd913c8a708af5e704b51d07503893b4365..7d55974dd9337f9843a2f2b3ef3e9335d246c9ac 100644
--- a/libcxx/test/std/utilities/memory/pointer.conversion/to_address.pass.cpp
+++ b/libcxx/test/std/utilities/memory/pointer.conversion/to_address.pass.cpp
@@ -99,7 +99,7 @@ struct pointer_traits<::P4>
 int n = 0;
 static_assert(std::to_address(&n) == &n);
 
-int main()
+int main(int, char**)
 {
     int i = 0;
     ASSERT_NOEXCEPT(std::to_address(&i));
@@ -116,4 +116,6 @@ int main()
     P4 p4(&i);
     ASSERT_NOEXCEPT(std::to_address(p4));
     assert(std::to_address(p4) == &i);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/pointer.traits/difference_type.pass.cpp b/libcxx/test/std/utilities/memory/pointer.traits/difference_type.pass.cpp
index 867bd46cd298935ba05f764ec2e98cc90863ab34..3eaedab16700bf19077ad43dc0a61e99e69cbfb3 100644
--- a/libcxx/test/std/utilities/memory/pointer.traits/difference_type.pass.cpp
+++ b/libcxx/test/std/utilities/memory/pointer.traits/difference_type.pass.cpp
@@ -18,7 +18,9 @@
 #include <memory>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::pointer_traits<double*>::difference_type, std::ptrdiff_t>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/pointer.traits/element_type.pass.cpp b/libcxx/test/std/utilities/memory/pointer.traits/element_type.pass.cpp
index 42db90ff6efaa2cdd58c96391c0358ea83494fe3..505881ddeeaf0eef9902badc80dc62c98638a49c 100644
--- a/libcxx/test/std/utilities/memory/pointer.traits/element_type.pass.cpp
+++ b/libcxx/test/std/utilities/memory/pointer.traits/element_type.pass.cpp
@@ -18,7 +18,9 @@
 #include <memory>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::pointer_traits<const short*>::element_type, const short>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/pointer.traits/pointer.pass.cpp b/libcxx/test/std/utilities/memory/pointer.traits/pointer.pass.cpp
index 4a74b5d589490db2ca36bdbe23b44baaaa7b2920..110a993dc6605e8df32e5bc8324ae79887eb83c4 100644
--- a/libcxx/test/std/utilities/memory/pointer.traits/pointer.pass.cpp
+++ b/libcxx/test/std/utilities/memory/pointer.traits/pointer.pass.cpp
@@ -24,8 +24,10 @@ struct A
     typedef char difference_type;
 };
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::pointer_traits<A>::pointer, A>::value), "");
     static_assert((std::is_same<std::pointer_traits<int*>::pointer, int*>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/pointer.traits/pointer.traits.functions/pointer_to.pass.cpp b/libcxx/test/std/utilities/memory/pointer.traits/pointer.traits.functions/pointer_to.pass.cpp
index 0b412dac4635be4308b08f30e5dc0a437cb5f9f0..9e6a48930e28de0d8298fc5f9a63ae1e73121ed3 100644
--- a/libcxx/test/std/utilities/memory/pointer.traits/pointer.traits.functions/pointer_to.pass.cpp
+++ b/libcxx/test/std/utilities/memory/pointer.traits/pointer.traits.functions/pointer_to.pass.cpp
@@ -34,7 +34,7 @@ public:
         {return A(&et);}
 };
 
-int main()
+int main(int, char**)
 {
     {
         int i = 0;
@@ -45,4 +45,6 @@ int main()
     {
         (std::pointer_traits<A<void> >::element_type)0;
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/pointer.traits/pointer.traits.types/difference_type.pass.cpp b/libcxx/test/std/utilities/memory/pointer.traits/pointer.traits.types/difference_type.pass.cpp
index 7e08235399ed2cf001bb7d6668a47904e32a971f..d4d763c69eaeca821828632b9beb613f31959d87 100644
--- a/libcxx/test/std/utilities/memory/pointer.traits/pointer.traits.types/difference_type.pass.cpp
+++ b/libcxx/test/std/utilities/memory/pointer.traits/pointer.traits.types/difference_type.pass.cpp
@@ -52,7 +52,7 @@ private:
   typedef int difference_type;
 };
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::pointer_traits<A>::difference_type, char>::value), "");
     static_assert((std::is_same<std::pointer_traits<B>::difference_type, std::ptrdiff_t>::value), "");
@@ -62,4 +62,6 @@ int main()
 #if TEST_STD_VER >= 11
     static_assert((std::is_same<std::pointer_traits<F<int>>::difference_type, std::ptrdiff_t>::value), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/pointer.traits/pointer.traits.types/element_type.pass.cpp b/libcxx/test/std/utilities/memory/pointer.traits/pointer.traits.types/element_type.pass.cpp
index 8184d2d0027746ba729325bb0694576263198715..c0efdeab0b31bdbf90ae3fb0e266274dee16c607 100644
--- a/libcxx/test/std/utilities/memory/pointer.traits/pointer.traits.types/element_type.pass.cpp
+++ b/libcxx/test/std/utilities/memory/pointer.traits/pointer.traits.types/element_type.pass.cpp
@@ -53,7 +53,7 @@ private:
   typedef int element_type;
 };
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::pointer_traits<A>::element_type, char>::value), "");
     static_assert((std::is_same<std::pointer_traits<B<int> >::element_type, char>::value), "");
@@ -64,4 +64,6 @@ int main()
     static_assert((std::is_same<std::pointer_traits<F<double>>::element_type, double>::value), "");
 #endif
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/pointer.traits/pointer.traits.types/rebind.pass.cpp b/libcxx/test/std/utilities/memory/pointer.traits/pointer.traits.types/rebind.pass.cpp
index 407f4bcfb9f9829fa0ad18be120b84fb283f32e0..a79f3391664620d6a734fbe87afde8dd309613f8 100644
--- a/libcxx/test/std/utilities/memory/pointer.traits/pointer.traits.types/rebind.pass.cpp
+++ b/libcxx/test/std/utilities/memory/pointer.traits/pointer.traits.types/rebind.pass.cpp
@@ -81,7 +81,7 @@ struct G
 #endif
 
 
-int main()
+int main(int, char**)
 {
 #if TEST_STD_VER >= 11
     static_assert((std::is_same<std::pointer_traits<A<int*> >::rebind<double*>, A<double*> >::value), "");
@@ -101,4 +101,6 @@ int main()
     static_assert((std::is_same<std::pointer_traits<D<char, int> >::rebind<double>::other, D1<double, int> >::value), "");
     static_assert((std::is_same<std::pointer_traits<E<char, int> >::rebind<double>::other, E<double, int> >::value), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/pointer.traits/pointer_to.pass.cpp b/libcxx/test/std/utilities/memory/pointer.traits/pointer_to.pass.cpp
index 968d3ee1e72d966ce754c2762abea4fb6b2f28e1..e9b858c7fd9439fbfe81f3c60a52a0d853e6d457 100644
--- a/libcxx/test/std/utilities/memory/pointer.traits/pointer_to.pass.cpp
+++ b/libcxx/test/std/utilities/memory/pointer.traits/pointer_to.pass.cpp
@@ -35,9 +35,11 @@ bool check() {
     return true;
 }
 
-int main() {
+int main(int, char**) {
     check();
 #if TEST_STD_VER > 17
     static_assert(check(), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/pointer.traits/rebind.pass.cpp b/libcxx/test/std/utilities/memory/pointer.traits/rebind.pass.cpp
index 823d4f11f23be21254492792230f742c2668aa87..f64213c9b887cebcab236c48f789ac31f7e1e017 100644
--- a/libcxx/test/std/utilities/memory/pointer.traits/rebind.pass.cpp
+++ b/libcxx/test/std/utilities/memory/pointer.traits/rebind.pass.cpp
@@ -20,11 +20,13 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 #if TEST_STD_VER >= 11
     static_assert((std::is_same<std::pointer_traits<int*>::rebind<double>, double*>::value), "");
 #else
     static_assert((std::is_same<std::pointer_traits<int*>::rebind<double>::other, double*>::value), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/ptr.align/align.pass.cpp b/libcxx/test/std/utilities/memory/ptr.align/align.pass.cpp
index c7a181eb79e01291d9860611ac70aff4e7c78b6a..3d0216cce53337afe756ad564c7e918d98dbb6f2 100644
--- a/libcxx/test/std/utilities/memory/ptr.align/align.pass.cpp
+++ b/libcxx/test/std/utilities/memory/ptr.align/align.pass.cpp
@@ -13,7 +13,7 @@
 #include <memory>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const unsigned N = 20;
     char buf[N];
@@ -80,4 +80,6 @@ int main()
     assert(p == &buf[0]);
     assert(r == nullptr);
     assert(s == N);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/specialized.algorithms/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/memory/specialized.algorithms/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/memory/specialized.algorithms/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/memory/specialized.algorithms/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/specialized.algorithms/specialized.addressof/addressof.pass.cpp b/libcxx/test/std/utilities/memory/specialized.algorithms/specialized.addressof/addressof.pass.cpp
index 956e6b1187c892aa957b07a5f2987c45163a8b7b..f6310c7bc911641f044e10a13cc417906d3ab7bb 100644
--- a/libcxx/test/std/utilities/memory/specialized.algorithms/specialized.addressof/addressof.pass.cpp
+++ b/libcxx/test/std/utilities/memory/specialized.algorithms/specialized.addressof/addressof.pass.cpp
@@ -26,7 +26,7 @@ struct nothing {
     }
 };
 
-int main()
+int main(int, char**)
 {
     {
     int i;
@@ -47,4 +47,6 @@ int main()
     };
     assert(std::addressof(n) == (void*)std::addressof(i));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/specialized.algorithms/specialized.addressof/addressof.temp.fail.cpp b/libcxx/test/std/utilities/memory/specialized.algorithms/specialized.addressof/addressof.temp.fail.cpp
index c12bf41e8ea71a926d1df8e5bf68757a9311751b..f7033014d3712d504ddaaf652360b90118a56fcb 100644
--- a/libcxx/test/std/utilities/memory/specialized.algorithms/specialized.addressof/addressof.temp.fail.cpp
+++ b/libcxx/test/std/utilities/memory/specialized.algorithms/specialized.addressof/addressof.temp.fail.cpp
@@ -15,11 +15,13 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 #if TEST_STD_VER > 14
     const int *p = std::addressof<const int>(0);
 #else
 #error
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/specialized.algorithms/specialized.addressof/constexpr_addressof.pass.cpp b/libcxx/test/std/utilities/memory/specialized.algorithms/specialized.addressof/constexpr_addressof.pass.cpp
index c042dd5c37b84f624db19b04fe85ee984ebe791d..f14a0e7fc898c245b7c3806c603e0de15410e8ab 100644
--- a/libcxx/test/std/utilities/memory/specialized.algorithms/specialized.addressof/constexpr_addressof.pass.cpp
+++ b/libcxx/test/std/utilities/memory/specialized.algorithms/specialized.addressof/constexpr_addressof.pass.cpp
@@ -32,10 +32,12 @@ constexpr int i = 0;
 constexpr double d = 0.0;
 constexpr A a{};
 
-int main()
+int main(int, char**)
 {
     static_assert(std::addressof(i) == &i, "");
     static_assert(std::addressof(d) == &d, "");
     constexpr const A* ap = std::addressof(a);
     static_assert(&ap->n == &a.n, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/specialized.algorithms/specialized.destroy/destroy.pass.cpp b/libcxx/test/std/utilities/memory/specialized.algorithms/specialized.destroy/destroy.pass.cpp
index f812bb85a625dd90b2b2c2b4bcea0955e1112282..4dbc20aba39c715a8a0d4eb4999685f12b182490 100644
--- a/libcxx/test/std/utilities/memory/specialized.algorithms/specialized.destroy/destroy.pass.cpp
+++ b/libcxx/test/std/utilities/memory/specialized.algorithms/specialized.destroy/destroy.pass.cpp
@@ -30,7 +30,7 @@ struct Counted {
 };
 int Counted::count = 0;
 
-int main()
+int main(int, char**)
 {
     using It = forward_iterator<Counted*>;
     const int N = 5;
@@ -43,4 +43,6 @@ int main()
     assert(Counted::count == 4);
     std::destroy(It(p), It(p + 4));
     assert(Counted::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/specialized.algorithms/specialized.destroy/destroy_at.pass.cpp b/libcxx/test/std/utilities/memory/specialized.algorithms/specialized.destroy/destroy_at.pass.cpp
index 28450faa10fb9d2bb26fbb7cbef25d675a72fd28..d505222b02d7d916d851db447c7bb9c600af0556 100644
--- a/libcxx/test/std/utilities/memory/specialized.algorithms/specialized.destroy/destroy_at.pass.cpp
+++ b/libcxx/test/std/utilities/memory/specialized.algorithms/specialized.destroy/destroy_at.pass.cpp
@@ -41,7 +41,7 @@ struct DCounted : VCounted {
     friend void operator&(DCounted) = delete;
 };
 
-int main()
+int main(int, char**)
 {
     {
     void* mem1 = std::malloc(sizeof(Counted));
@@ -74,4 +74,6 @@ int main()
     std::free(mem1);
     std::free(mem2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/specialized.algorithms/specialized.destroy/destroy_n.pass.cpp b/libcxx/test/std/utilities/memory/specialized.algorithms/specialized.destroy/destroy_n.pass.cpp
index 90836b2335518d0e1b3d5cc29e7a480e79e6d682..0dcc8e5a657985bce44de3b216412ab8d1a14d63 100644
--- a/libcxx/test/std/utilities/memory/specialized.algorithms/specialized.destroy/destroy_n.pass.cpp
+++ b/libcxx/test/std/utilities/memory/specialized.algorithms/specialized.destroy/destroy_n.pass.cpp
@@ -30,7 +30,7 @@ struct Counted {
 };
 int Counted::count = 0;
 
-int main()
+int main(int, char**)
 {
     using It = forward_iterator<Counted*>;
     const int N = 5;
@@ -45,4 +45,6 @@ int main()
     It it = std::destroy_n(It(p), 4);
     assert(it == It(p+4));
     assert(Counted::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.construct.default/uninitialized_default_construct.pass.cpp b/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.construct.default/uninitialized_default_construct.pass.cpp
index bd9ef7b403fa7d7b732dd3a9cf791df250c75d9a..67dd6fbd2984abe4e07da6879d689ae0c2c7f79a 100644
--- a/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.construct.default/uninitialized_default_construct.pass.cpp
+++ b/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.construct.default/uninitialized_default_construct.pass.cpp
@@ -103,9 +103,11 @@ void test_value_initialized()
     assert(pool[4] == -1);
 }
 
-int main()
+int main(int, char**)
 {
     test_counted();
     test_value_initialized();
     test_ctor_throws();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.construct.default/uninitialized_default_construct_n.pass.cpp b/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.construct.default/uninitialized_default_construct_n.pass.cpp
index d2f6e094a85f2702670c5c8cbc1ad14428ef22be..1052355a4f22e7224935127aa22e700745caf73f 100644
--- a/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.construct.default/uninitialized_default_construct_n.pass.cpp
+++ b/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.construct.default/uninitialized_default_construct_n.pass.cpp
@@ -107,9 +107,11 @@ void test_value_initialized()
 }
 
 
-int main()
+int main(int, char**)
 {
     test_counted();
     test_value_initialized();
     test_ctor_throws();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.construct.value/uninitialized_value_construct.pass.cpp b/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.construct.value/uninitialized_value_construct.pass.cpp
index 50ce122484814d9e803f8b4d3c6400dc8397a538..5dfcd83fe9bbb0df5d41ac453448e07caf5e6c88 100644
--- a/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.construct.value/uninitialized_value_construct.pass.cpp
+++ b/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.construct.value/uninitialized_value_construct.pass.cpp
@@ -102,9 +102,11 @@ void test_value_initialized()
     assert(pool[4] == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test_counted();
     test_value_initialized();
     test_ctor_throws();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.construct.value/uninitialized_value_construct_n.pass.cpp b/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.construct.value/uninitialized_value_construct_n.pass.cpp
index 4d89f9cac4c6bcaf4d3ef04821783dfb2b4d5b0b..e43102ba4aac469a41203947feb31bb22981c748 100644
--- a/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.construct.value/uninitialized_value_construct_n.pass.cpp
+++ b/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.construct.value/uninitialized_value_construct_n.pass.cpp
@@ -107,8 +107,10 @@ void test_value_initialized()
     assert(pool[4] == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test_counted();
     test_value_initialized();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.copy/uninitialized_copy.pass.cpp b/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.copy/uninitialized_copy.pass.cpp
index b81d561e089695f60331d2c5c47caaac7d66dc59..2618bd5339c9edc71d83613ae06a3aa9410bd413 100644
--- a/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.copy/uninitialized_copy.pass.cpp
+++ b/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.copy/uninitialized_copy.pass.cpp
@@ -47,7 +47,7 @@ struct Nasty
 
 int Nasty::counter_ = 0;
 
-int main()
+int main(int, char**)
 {
     {
     const int N = 5;
@@ -85,4 +85,6 @@ int main()
         }
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.copy/uninitialized_copy_n.pass.cpp b/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.copy/uninitialized_copy_n.pass.cpp
index c3f46bebe67057a064f15256bc9febb4c7624fc9..1a237a7929dbc082e5bfbba70cf1ad96634c2fc0 100644
--- a/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.copy/uninitialized_copy_n.pass.cpp
+++ b/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.copy/uninitialized_copy_n.pass.cpp
@@ -47,7 +47,7 @@ struct Nasty
 
 int Nasty::counter_ = 0;
 
-int main()
+int main(int, char**)
 {
     {
     const int N = 5;
@@ -84,4 +84,6 @@ int main()
         assert(  p[i].i_ == i);
     }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.fill.n/uninitialized_fill_n.pass.cpp b/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.fill.n/uninitialized_fill_n.pass.cpp
index 5c177663e400994c585624dc45bd859111627426..4dfde4f6e877cd6f3b1c2e9650bbb1187bf3db00 100644
--- a/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.fill.n/uninitialized_fill_n.pass.cpp
+++ b/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.fill.n/uninitialized_fill_n.pass.cpp
@@ -46,7 +46,7 @@ struct Nasty
 
 int Nasty::counter_ = 0;
 
-int main()
+int main(int, char**)
 {
     {
     const int N = 5;
@@ -84,4 +84,6 @@ int main()
     }
 
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.fill/uninitialized_fill.pass.cpp b/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.fill/uninitialized_fill.pass.cpp
index f7790fc4519f4d13ada039babdbc5c021f29eeef..1996ec6c6fffa8214060c8ecae22fdbeae7ab12e 100644
--- a/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.fill/uninitialized_fill.pass.cpp
+++ b/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.fill/uninitialized_fill.pass.cpp
@@ -47,7 +47,7 @@ struct Nasty
 
 int Nasty::counter_ = 0;
 
-int main()
+int main(int, char**)
 {
     {
     const int N = 5;
@@ -81,4 +81,6 @@ int main()
     for (int i = 0; i < N; ++i)
         assert(bp[i].i_ == 23);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.move/uninitialized_move.pass.cpp b/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.move/uninitialized_move.pass.cpp
index a0717e61b2ca075df45519786271813b28ed205e..e17f5734bb26d6b86edecb24a26ea8d4f049fee1 100644
--- a/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.move/uninitialized_move.pass.cpp
+++ b/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.move/uninitialized_move.pass.cpp
@@ -107,7 +107,9 @@ void test_counted()
     assert(Counted::count == 0);
 }
 
-int main() {
+int main(int, char**) {
     test_counted();
     test_ctor_throws();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.move/uninitialized_move_n.pass.cpp b/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.move/uninitialized_move_n.pass.cpp
index 755384074215af2b8aca4f4d99e02bd0b2662693..ee364aaf5b9b6b283e62c9c3ce93d7ae7b5b410e 100644
--- a/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.move/uninitialized_move_n.pass.cpp
+++ b/libcxx/test/std/utilities/memory/specialized.algorithms/uninitialized.move/uninitialized_move_n.pass.cpp
@@ -109,8 +109,10 @@ void test_counted()
     assert(Counted::count == 0);
 }
 
-int main()
+int main(int, char**)
 {
     test_counted();
     test_ctor_throws();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/storage.iterator/raw_storage_iterator.base.pass.cpp b/libcxx/test/std/utilities/memory/storage.iterator/raw_storage_iterator.base.pass.cpp
index 531158ba1585b0bb3ac7f390bf53535f26ce2f25..5355d09ac26beedc5f3c07ecd58843fc404cf9b4 100644
--- a/libcxx/test/std/utilities/memory/storage.iterator/raw_storage_iterator.base.pass.cpp
+++ b/libcxx/test/std/utilities/memory/storage.iterator/raw_storage_iterator.base.pass.cpp
@@ -36,7 +36,7 @@ public:
     A* operator& () DELETE_FUNCTION;
 };
 
-int main()
+int main(int, char**)
 {
 #if TEST_STD_VER >= 14
     typedef std::aligned_storage<3*sizeof(A), std::alignment_of<A>::value>::type
@@ -54,4 +54,6 @@ int main()
         assert(it.base() == ap + 1);  // next place to write
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/storage.iterator/raw_storage_iterator.pass.cpp b/libcxx/test/std/utilities/memory/storage.iterator/raw_storage_iterator.pass.cpp
index 90bb956fc03d8de38aad6d3e17973201ce01d7ae..2b9b33fd9b998b812e743a6be583038b3745dd8a 100644
--- a/libcxx/test/std/utilities/memory/storage.iterator/raw_storage_iterator.pass.cpp
+++ b/libcxx/test/std/utilities/memory/storage.iterator/raw_storage_iterator.pass.cpp
@@ -36,7 +36,7 @@ public:
     A* operator& () DELETE_FUNCTION;
 };
 
-int main()
+int main(int, char**)
 {
     {
     typedef A S;
@@ -67,4 +67,6 @@ int main()
     assert(ap->get() == 1); // original value
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/temporary.buffer/overaligned.pass.cpp b/libcxx/test/std/utilities/memory/temporary.buffer/overaligned.pass.cpp
index fd818577b0627704273469fbc7aaa1d0a94b39d6..db71c69bf26cd688c0a77ce0a3bcad90e314e32b 100644
--- a/libcxx/test/std/utilities/memory/temporary.buffer/overaligned.pass.cpp
+++ b/libcxx/test/std/utilities/memory/temporary.buffer/overaligned.pass.cpp
@@ -25,10 +25,12 @@ struct alignas(32) A {
     int field;
 };
 
-int main()
+int main(int, char**)
 {
     std::pair<A*, std::ptrdiff_t> ip = std::get_temporary_buffer<A>(5);
     assert(!(ip.first == nullptr) ^ (ip.second == 0));
     assert(reinterpret_cast<uintptr_t>(ip.first) % alignof(A) == 0);
     std::return_temporary_buffer(ip.first);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/temporary.buffer/temporary_buffer.pass.cpp b/libcxx/test/std/utilities/memory/temporary.buffer/temporary_buffer.pass.cpp
index 22efde4af8fff779a98d63a0efa34dd4bca52498..32a58e5a657be7cf8f9700d1da4b8d06dc16f743 100644
--- a/libcxx/test/std/utilities/memory/temporary.buffer/temporary_buffer.pass.cpp
+++ b/libcxx/test/std/utilities/memory/temporary.buffer/temporary_buffer.pass.cpp
@@ -19,10 +19,12 @@
 #include <memory>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::pair<int*, std::ptrdiff_t> ip = std::get_temporary_buffer<int>(5);
     assert(ip.first);
     assert(ip.second == 5);
     std::return_temporary_buffer(ip.first);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/unique.ptr/unique.ptr.special/io.fail.cpp b/libcxx/test/std/utilities/memory/unique.ptr/unique.ptr.special/io.fail.cpp
index c9d1c8b46975eda7c89b6e04482fad1835d63f9d..bc6846fe7f5df857a18dae59de26842a08186745 100644
--- a/libcxx/test/std/utilities/memory/unique.ptr/unique.ptr.special/io.fail.cpp
+++ b/libcxx/test/std/utilities/memory/unique.ptr/unique.ptr.special/io.fail.cpp
@@ -26,9 +26,11 @@
 #include "min_allocator.h"
 #include "deleter_types.h"
 
-int main()
+int main(int, char**)
 {
     std::unique_ptr<int, PointerDeleter<int>> p;
     std::ostringstream os;
     os << p; // expected-error {{invalid operands to binary expression}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/unique.ptr/unique.ptr.special/io.pass.cpp b/libcxx/test/std/utilities/memory/unique.ptr/unique.ptr.special/io.pass.cpp
index e350a0385d6573eda6dc964ee7207e2ce8807662..b9b158a9d2b741badeeb2a7251f04ed3f8b6bc9c 100644
--- a/libcxx/test/std/utilities/memory/unique.ptr/unique.ptr.special/io.pass.cpp
+++ b/libcxx/test/std/utilities/memory/unique.ptr/unique.ptr.special/io.pass.cpp
@@ -21,11 +21,13 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::unique_ptr<int> p(new int(3));
     std::ostringstream os;
     assert(os.str().empty());
     os << p;
     assert(!os.str().empty());
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.dynamic.safety/declare_no_pointers.pass.cpp b/libcxx/test/std/utilities/memory/util.dynamic.safety/declare_no_pointers.pass.cpp
index 5c99a9721a0f9918fd356d6b931b8c2ef103afd8..a2b6cf22ed8feff31255a2546949e45ebb3bd814 100644
--- a/libcxx/test/std/utilities/memory/util.dynamic.safety/declare_no_pointers.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.dynamic.safety/declare_no_pointers.pass.cpp
@@ -13,10 +13,12 @@
 
 #include <memory>
 
-int main()
+int main(int, char**)
 {
     char* p = new char[10];
     std::declare_no_pointers(p, 10);
     std::undeclare_no_pointers(p, 10);
     delete [] p;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.dynamic.safety/declare_reachable.pass.cpp b/libcxx/test/std/utilities/memory/util.dynamic.safety/declare_reachable.pass.cpp
index 4a71817d4037e551b563dbd846df88f8b8ebc491..c923089fa978d875af9a289666e37377eeb51e89 100644
--- a/libcxx/test/std/utilities/memory/util.dynamic.safety/declare_reachable.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.dynamic.safety/declare_reachable.pass.cpp
@@ -14,10 +14,12 @@
 #include <memory>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     int* p = new int;
     std::declare_reachable(p);
     assert(std::undeclare_reachable(p) == p);
     delete p;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.dynamic.safety/get_pointer_safety.pass.cpp b/libcxx/test/std/utilities/memory/util.dynamic.safety/get_pointer_safety.pass.cpp
index 4fc2e010f793e1e35a4e7db00b3a849348238f9e..2fea98364b479b14a63bdd481aa8e06e5a2bcb3c 100644
--- a/libcxx/test/std/utilities/memory/util.dynamic.safety/get_pointer_safety.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.dynamic.safety/get_pointer_safety.pass.cpp
@@ -22,7 +22,7 @@ void test_pr26961() {
   assert(d == std::get_pointer_safety());
 }
 
-int main()
+int main(int, char**)
 {
   {
     std::pointer_safety r = std::get_pointer_safety();
@@ -33,4 +33,6 @@ int main()
   {
     test_pr26961();
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.enab/enable_shared_from_this.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.enab/enable_shared_from_this.pass.cpp
index 0f7c44fd8fdde30bc4513a8ccf763ea7251e4779..fe7567eebc14d955d73739c8c957ccb2d84c21a5 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.enab/enable_shared_from_this.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.enab/enable_shared_from_this.pass.cpp
@@ -52,7 +52,7 @@ struct PrivateBase : private std::enable_shared_from_this<PrivateBase> {
 };
 
 
-int main()
+int main(int, char**)
 {
     {  // https://bugs.llvm.org/show_bug.cgi?id=18843
     std::shared_ptr<T const> t1(new T);
@@ -167,4 +167,6 @@ int main()
         assert(my_weak.lock().get() == ptr);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.hash/enabled_hash.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.hash/enabled_hash.pass.cpp
index bd7f644c3ec465c1b30b9eb7d6f8761fa2087193..440fa8ac480d9d2788a81f2e87e1110883258126 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.hash/enabled_hash.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.hash/enabled_hash.pass.cpp
@@ -17,6 +17,8 @@
 
 #include "poisoned_hash_helper.hpp"
 
-int main() {
+int main(int, char**) {
   test_library_hash_specializations_available();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.hash/hash_shared_ptr.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.hash/hash_shared_ptr.pass.cpp
index 8db542c079467d042ae4e3c95ce9eb83b70ae24d..34717ad4256ac8994bbd5ec142522bcc074ea720 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.hash/hash_shared_ptr.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.hash/hash_shared_ptr.pass.cpp
@@ -25,7 +25,7 @@
 struct A {};
 #endif
 
-int main()
+int main(int, char**)
 {
   {
     int* ptr = new int;
@@ -40,4 +40,6 @@ int main()
     test_hash_enabled_for_type<std::shared_ptr<A>>();
   }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.hash/hash_unique_ptr.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.hash/hash_unique_ptr.pass.cpp
index 4f942f6c2d92155355002c26df07bbd1e9d740da..5cae6ca7d458f53ec89d99faa17ec6aa7545c443 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.hash/hash_unique_ptr.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.hash/hash_unique_ptr.pass.cpp
@@ -60,7 +60,7 @@ struct A {};
 
 #endif // TEST_STD_VER >= 11
 
-int main()
+int main(int, char**)
 {
   {
     int* ptr = new int;
@@ -99,4 +99,6 @@ int main()
 #endif
   }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_compare_exchange_strong.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_compare_exchange_strong.pass.cpp
index 45c82c4bafa176e982409fc52a52b81e68fe154f..7737cfd4da099befe9507d6eaf42e634f41419be 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_compare_exchange_strong.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_compare_exchange_strong.pass.cpp
@@ -29,7 +29,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::shared_ptr<int> p(new int(4));
@@ -51,4 +51,6 @@ int main()
         assert(*v == 4);
         assert(*w == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_compare_exchange_strong_explicit.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_compare_exchange_strong_explicit.pass.cpp
index d1589aaddba83ce35d47f50455f9f30e869181de..9198ca68cd8fa10785f1c902dc1fba7fbe89921d 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_compare_exchange_strong_explicit.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_compare_exchange_strong_explicit.pass.cpp
@@ -30,7 +30,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::shared_ptr<int> p(new int(4));
@@ -56,4 +56,6 @@ int main()
         assert(*v == 4);
         assert(*w == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_compare_exchange_weak.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_compare_exchange_weak.pass.cpp
index fb09a19fd058d3295b88cceb5f0424b744ffb629..da52811c9c03315c8211b7abd2eec6df75499480 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_compare_exchange_weak.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_compare_exchange_weak.pass.cpp
@@ -29,7 +29,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::shared_ptr<int> p(new int(4));
@@ -51,4 +51,6 @@ int main()
         assert(*v == 4);
         assert(*w == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_compare_exchange_weak_explicit.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_compare_exchange_weak_explicit.pass.cpp
index 2a9b6ce1244922b14eaf86f5f07f5b414f18a2da..703bf008f4f827affecc5b9a2dcc6c072be2d299 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_compare_exchange_weak_explicit.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_compare_exchange_weak_explicit.pass.cpp
@@ -30,7 +30,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::shared_ptr<int> p(new int(4));
@@ -56,4 +56,6 @@ int main()
         assert(*v == 4);
         assert(*w == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_exchange.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_exchange.pass.cpp
index cf6ad5b0037c5f849f65b8911889acb3fb9af25a..b51a24aefb931bc2337c032079dfa1ea6863a7a6 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_exchange.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_exchange.pass.cpp
@@ -28,7 +28,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::shared_ptr<int> p(new int(4));
@@ -37,4 +37,6 @@ int main()
         assert(*p == 3);
         assert(*r == 4);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_exchange_explicit.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_exchange_explicit.pass.cpp
index f177420fe94eb64c7beb3e05b6e13131b3aed3fb..b59b515a5c2ee6187af81a1215357a49fde0d9b7 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_exchange_explicit.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_exchange_explicit.pass.cpp
@@ -28,7 +28,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::shared_ptr<int> p(new int(4));
@@ -37,4 +37,6 @@ int main()
         assert(*p == 3);
         assert(*r == 4);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_is_lock_free.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_is_lock_free.pass.cpp
index 3b267f99d0925bbd54d29529d91026345dcaf6be..e8bb64dccb6f34b8146796ed75667c78eb1bfa1b 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_is_lock_free.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_is_lock_free.pass.cpp
@@ -23,10 +23,12 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         const std::shared_ptr<int> p(new int(3));
         assert(std::atomic_is_lock_free(&p) == false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_load.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_load.pass.cpp
index b36580ef21718202d39fe67ecf5fb534c94d67c4..63416faf3299ab33c338da1fb748f98241c29e1d 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_load.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_load.pass.cpp
@@ -28,11 +28,13 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::shared_ptr<int> p(new int(3));
         std::shared_ptr<int> q = std::atomic_load(&p);
         assert(*q == *p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_load_explicit.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_load_explicit.pass.cpp
index 40f6b49d6c661366ddb51087416a42e67f78c50f..0708f874b2696c9988525af6aa2145419fca48d8 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_load_explicit.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_load_explicit.pass.cpp
@@ -28,11 +28,13 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         const std::shared_ptr<int> p(new int(3));
         std::shared_ptr<int> q = std::atomic_load_explicit(&p, std::memory_order_relaxed);
         assert(*q == *p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_store.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_store.pass.cpp
index 3c6de40f1179130ef4fcfe451046c7259fd99a7b..42d7099a9df0cb35bdbcf7b5752bd0c1d0d81cf7 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_store.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_store.pass.cpp
@@ -28,7 +28,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::shared_ptr<int> p;
@@ -36,4 +36,6 @@ int main()
         std::atomic_store(&p, r);
         assert(*p == *r);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_store_explicit.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_store_explicit.pass.cpp
index dd4001a82ff59ccb3349b4a1292113c0c437a9d2..7da4de3fa47f84703bc86728b3ccdc9ca375483e 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_store_explicit.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared.atomic/atomic_store_explicit.pass.cpp
@@ -28,7 +28,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::shared_ptr<int> p;
@@ -36,4 +36,6 @@ int main()
         std::atomic_store_explicit(&p, r, std::memory_order_seq_cst);
         assert(*p == *r);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/types.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/types.pass.cpp
index 4a96f8181b2d06e9768f5f65578a478bbb50341e..c3aedd5b1ad27e7c90fe5fb02386f0bd1a2b7fa0 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/types.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/types.pass.cpp
@@ -22,10 +22,12 @@
 
 struct A;  // purposefully incomplete
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::shared_ptr<A>::element_type, A>::value), "");
 #if TEST_STD_VER > 14
     static_assert((std::is_same<std::shared_ptr<A>::weak_type, std::weak_ptr<A>>::value), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.getdeleter/get_deleter.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.getdeleter/get_deleter.pass.cpp
index babf1c6ee5ba4b4ba0062c39770d85f84acd55c0..209e3fe71af4db060bf73f813c297b46a697bdb1 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.getdeleter/get_deleter.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.getdeleter/get_deleter.pass.cpp
@@ -27,7 +27,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         {
@@ -63,4 +63,6 @@ int main()
         std::default_delete<A>* d = std::get_deleter<std::default_delete<A> >(p);
         assert(d == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.assign/auto_ptr_Y.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.assign/auto_ptr_Y.pass.cpp
index 69ad9513b6c53d5d7b349d62ee7c059cc6d16d16..a154a121c7fac58f20cd81da35dc110c50684873 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.assign/auto_ptr_Y.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.assign/auto_ptr_Y.pass.cpp
@@ -40,7 +40,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::auto_ptr<A> pA(new A);
@@ -110,4 +110,6 @@ int main()
     }
     assert(B::count == 0);
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.assign/shared_ptr.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.assign/shared_ptr.pass.cpp
index 6d2000c1375fc39f1681ebc806a39a184aee0c1a..e362f4d8d4e42b9d53fc7b2088d77886efdaba6c 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.assign/shared_ptr.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.assign/shared_ptr.pass.cpp
@@ -39,7 +39,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         const std::shared_ptr<A> pA(new A);
@@ -117,4 +117,6 @@ int main()
     }
     assert(B::count == 0);
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.assign/shared_ptr_Y.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.assign/shared_ptr_Y.pass.cpp
index 23b587d0b7d72d539b2f3921b4e2651fb4447a51..2b666315ef2f866b7243845c91ba32f7f65b8efc 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.assign/shared_ptr_Y.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.assign/shared_ptr_Y.pass.cpp
@@ -39,7 +39,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         const std::shared_ptr<A> pA(new A);
@@ -117,4 +117,6 @@ int main()
     }
     assert(B::count == 0);
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.assign/shared_ptr_Y_rv.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.assign/shared_ptr_Y_rv.pass.cpp
index a3ba5877f490c1881b12b3f49d85ee2a76938a3f..6787c33c297f1d371de55de0f9212fee49860ac0 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.assign/shared_ptr_Y_rv.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.assign/shared_ptr_Y_rv.pass.cpp
@@ -41,7 +41,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::shared_ptr<A> pA(new A);
@@ -119,4 +119,6 @@ int main()
     }
     assert(B::count == 0);
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.assign/shared_ptr_rv.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.assign/shared_ptr_rv.pass.cpp
index 8c63b14b27d8b458892188ff767e70c6b4fca4af..e921a09918985b23fc61ff18998706215733aeba 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.assign/shared_ptr_rv.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.assign/shared_ptr_rv.pass.cpp
@@ -41,7 +41,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::shared_ptr<A> pA(new A);
@@ -119,4 +119,6 @@ int main()
     }
     assert(B::count == 0);
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.assign/unique_ptr_Y.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.assign/unique_ptr_Y.pass.cpp
index b7fc447b05710314cc0c18c950b82b57e5bb2607..4abe371bc074795068525039087589a7e32cbc34 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.assign/unique_ptr_Y.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.assign/unique_ptr_Y.pass.cpp
@@ -39,7 +39,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::unique_ptr<A> pA(new A);
@@ -109,4 +109,6 @@ int main()
     }
     assert(B::count == 0);
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.cast/const_pointer_cast.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.cast/const_pointer_cast.pass.cpp
index 53955aaa2185534f3616d788ea1e0b5f2320e257..51e2949b6c609ff9e61465d70cd86deca60eafb4 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.cast/const_pointer_cast.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.cast/const_pointer_cast.pass.cpp
@@ -39,7 +39,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         const std::shared_ptr<const A> pA(new A);
@@ -53,4 +53,6 @@ int main()
         assert(pB.get() == pA.get());
         assert(!pB.owner_before(pA) && !pA.owner_before(pB));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.cast/dynamic_pointer_cast.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.cast/dynamic_pointer_cast.pass.cpp
index c27f9503b62a5f4214c26758a3b7f372cb59aec0..76009b96abde8558b3b058cb7d0ef9452c4b52fe 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.cast/dynamic_pointer_cast.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.cast/dynamic_pointer_cast.pass.cpp
@@ -39,7 +39,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         const std::shared_ptr<B> pB(new A);
@@ -53,4 +53,6 @@ int main()
         assert(pA.get() == 0);
         assert(pA.use_count() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.cast/static_pointer_cast.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.cast/static_pointer_cast.pass.cpp
index ec72834d5cdffb5fecae43580552818683902e13..9ea544fee012373151fb6d89699ffe342cdd6706 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.cast/static_pointer_cast.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.cast/static_pointer_cast.pass.cpp
@@ -39,7 +39,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         const std::shared_ptr<A> pA(new A);
@@ -65,4 +65,6 @@ int main()
         assert(pB.get() == pA.get());
         assert(!pB.owner_before(pA) && !pA.owner_before(pB));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.cmp/cmp_nullptr.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.cmp/cmp_nullptr.pass.cpp
index 6936744c1abe5bf43e8ff20532d4141537f9740a..98b5bbf0d67d9a71d823d409ac9b070941453f31 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.cmp/cmp_nullptr.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.cmp/cmp_nullptr.pass.cpp
@@ -40,7 +40,7 @@
 
 void do_nothing(int*) {}
 
-int main()
+int main(int, char**)
 {
     const std::shared_ptr<int> p1(new int(1));
     assert(!(p1 == nullptr));
@@ -65,4 +65,6 @@ int main()
     assert(!(nullptr > p2));
     assert( (p2 >= nullptr));
     assert( (nullptr >= p2));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.cmp/eq.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.cmp/eq.pass.cpp
index 1257ea65fd838567bcee378a55e54f895032f98e..e25ba611744aa9466875bb82646b0b14d6888155 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.cmp/eq.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.cmp/eq.pass.cpp
@@ -18,7 +18,7 @@
 
 void do_nothing(int*) {}
 
-int main()
+int main(int, char**)
 {
     int* ptr1(new int);
     int* ptr2(new int);
@@ -27,4 +27,6 @@ int main()
     const std::shared_ptr<int> p3(ptr2, do_nothing);
     assert(p1 != p2);
     assert(p2 == p3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.cmp/lt.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.cmp/lt.pass.cpp
index 15e13688b4df817e9a23d6f92cf3880fd894006b..fdef32d518ac44b4443989e34c050c60a01c19a9 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.cmp/lt.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.cmp/lt.pass.cpp
@@ -17,7 +17,7 @@
 
 void do_nothing(int*) {}
 
-int main()
+int main(int, char**)
 {
     int* ptr1(new int);
     int* ptr2(new int);
@@ -26,4 +26,6 @@ int main()
     const std::shared_ptr<int> p3(ptr2, do_nothing);
     assert((p1 < p2) == (ptr1 < ptr2));
     assert(!(p2 < p3) && !(p3 < p2));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/auto_ptr.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/auto_ptr.pass.cpp
index 6558e230dffd15f17353e9f99f03567a06d19029..282ddd0e0ead3f45d213c033b15ce8c399750035 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/auto_ptr.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/auto_ptr.pass.cpp
@@ -43,7 +43,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::auto_ptr<A> ptr(new A);
@@ -94,4 +94,6 @@ int main()
     assert(A::count == 0);
     assert(globalMemCounter.checkOutstandingNewEq(0));
 #endif // !defined(TEST_HAS_NO_EXCEPTIONS) && !defined(DISABLE_NEW_COUNT)
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/default.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/default.pass.cpp
index c70e537a9afba2c2c9ea6b4d4e55f0e8448ab1fa..247ca0fa924f7bb8dec41b7f2ddc43b5d8948622 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/default.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/default.pass.cpp
@@ -13,9 +13,11 @@
 #include <memory>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::shared_ptr<int> p;
     assert(p.use_count() == 0);
     assert(p.get() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/nullptr_t.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/nullptr_t.pass.cpp
index a46b31aa5a9e9cf0bbd61b67f5ebc20d218babbb..f29dd1cf7ea8182289058161d292264eb43081c3 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/nullptr_t.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/nullptr_t.pass.cpp
@@ -13,9 +13,11 @@
 #include <memory>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::shared_ptr<int> p(nullptr);
     assert(p.use_count() == 0);
     assert(p.get() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/nullptr_t_deleter.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/nullptr_t_deleter.pass.cpp
index 9644e4f0f991bd3516b1cc92cd9ce4466d8bdc2f..ee5861122bfc0a842eb61b543321d449f94aba18 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/nullptr_t_deleter.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/nullptr_t_deleter.pass.cpp
@@ -27,7 +27,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
     std::shared_ptr<A> p(nullptr, test_deleter<A>(3));
@@ -43,4 +43,6 @@ int main()
     assert(A::count == 0);
     assert(test_deleter<A>::count == 0);
     assert(test_deleter<A>::dealloc_count == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/nullptr_t_deleter_allocator.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/nullptr_t_deleter_allocator.pass.cpp
index bc1d3584e1e78099f4530ad6b4cff82d15e79a3f..0881e8cf42d2440205011ca7bb92f544e5b6eac9 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/nullptr_t_deleter_allocator.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/nullptr_t_deleter_allocator.pass.cpp
@@ -27,7 +27,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
     std::shared_ptr<A> p(nullptr, test_deleter<A>(3), test_allocator<A>(5));
@@ -81,4 +81,6 @@ int main()
     assert(test_deleter<A>::count == 0);
     assert(test_deleter<A>::dealloc_count == 1);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/nullptr_t_deleter_allocator_throw.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/nullptr_t_deleter_allocator_throw.pass.cpp
index 1948c6860ab6267002efeca127393d4fb436783a..4700df0085c3e06c7f708a9380cc112f5f000f0c 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/nullptr_t_deleter_allocator_throw.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/nullptr_t_deleter_allocator_throw.pass.cpp
@@ -27,7 +27,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     try
     {
@@ -43,4 +43,6 @@ int main()
         assert(test_allocator<A>::count == 0);
         assert(test_allocator<A>::alloc_count == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/nullptr_t_deleter_throw.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/nullptr_t_deleter_throw.pass.cpp
index 075cadf43d6a79cfb8351898029c0ebe96c738b0..7d2628d60dcb5dc53aa592ba8dee14ea5f8b4c7a 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/nullptr_t_deleter_throw.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/nullptr_t_deleter_throw.pass.cpp
@@ -37,7 +37,7 @@ struct A
 int A::count = 0;
 
 
-int main()
+int main(int, char**)
 {
     globalMemCounter.throw_after = 0;
     try
@@ -51,4 +51,6 @@ int main()
         assert(test_deleter<A>::count == 0);
         assert(test_deleter<A>::dealloc_count == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer.pass.cpp
index 67f0ffd2a809dbdc7e8e96d8311bf04d130ab10f..b55d764a6c413ca9a7ab502d759c3844f663f707 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer.pass.cpp
@@ -24,7 +24,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
     A* ptr = new A;
@@ -42,4 +42,6 @@ int main()
     assert(p.get() == ptr);
     }
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer_deleter.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer_deleter.pass.cpp
index 120171456be6eb9a61bd4d3486129fbbc8c93b91..fd98193826e1f1b371c602641f6af7b2542dd9ee 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer_deleter.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer_deleter.pass.cpp
@@ -27,7 +27,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
     A* ptr = new A;
@@ -44,4 +44,6 @@ int main()
     assert(A::count == 0);
     assert(test_deleter<A>::count == 0);
     assert(test_deleter<A>::dealloc_count == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer_deleter_allocator.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer_deleter_allocator.pass.cpp
index 79a0bc84a39d3937f3959ae13082112b59ea63ee..0ec18a7aebd523d1e0572ca8b9ad596b68745369 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer_deleter_allocator.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer_deleter_allocator.pass.cpp
@@ -28,7 +28,7 @@ struct A
 int A::count = 0;
 
 
-int main()
+int main(int, char**)
 {
     {
     A* ptr = new A;
@@ -85,4 +85,6 @@ int main()
     assert(test_deleter<A>::count == 0);
     assert(test_deleter<A>::dealloc_count == 1);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer_deleter_allocator_throw.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer_deleter_allocator_throw.pass.cpp
index ad020f89fd38f4b8b32844f943ad61b80712cd21..5f2984c7e22d2ce0b7bcd727420a01a620e5b6bb 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer_deleter_allocator_throw.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer_deleter_allocator_throw.pass.cpp
@@ -27,7 +27,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     A* ptr = new A;
     try
@@ -44,4 +44,6 @@ int main()
         assert(test_allocator<A>::count == 0);
         assert(test_allocator<A>::alloc_count == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer_deleter_throw.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer_deleter_throw.pass.cpp
index 6af99aaf55ec3f94d358fa9efa33bf9bca975753..da12e42ca0b2cdf1beff69fdcace4ffbcacdc96a 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer_deleter_throw.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer_deleter_throw.pass.cpp
@@ -34,7 +34,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     A* ptr = new A;
     globalMemCounter.throw_after = 0;
@@ -50,4 +50,6 @@ int main()
         assert(test_deleter<A>::dealloc_count == 1);
     }
     assert(globalMemCounter.checkOutstandingNewEq(0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer_throw.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer_throw.pass.cpp
index 95da6f691061b4e11ecd19035cc3aec38ca275fb..15e776003d9dd597d08930b30023ffd068681353 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer_throw.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/pointer_throw.pass.cpp
@@ -33,7 +33,7 @@ struct A
 int A::count = 0;
 
 
-int main()
+int main(int, char**)
 {
     A* ptr = new A;
     assert(A::count == 1);
@@ -48,4 +48,6 @@ int main()
         assert(A::count == 0);
     }
     assert(globalMemCounter.checkOutstandingNewEq(0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/shared_ptr.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/shared_ptr.pass.cpp
index 44a5be4714bed151e06bad6ec76f3ff2f82b3eb8..091782f02f3aa6dd03133b6811ba32d80b80d176 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/shared_ptr.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/shared_ptr.pass.cpp
@@ -26,7 +26,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::shared_ptr<A> pA(new A);
@@ -58,4 +58,6 @@ int main()
         assert(A::count == 0);
     }
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/shared_ptr_Y.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/shared_ptr_Y.pass.cpp
index 3b7279087ffc6ce227835403bc703aa38741f766..01a74898f9cb38a0e8990134eb0fed75b34ecd5d 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/shared_ptr_Y.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/shared_ptr_Y.pass.cpp
@@ -50,7 +50,7 @@ struct C
 
 int C::count = 0;
 
-int main()
+int main(int, char**)
 {
     static_assert(( std::is_convertible<std::shared_ptr<A>, std::shared_ptr<B> >::value), "");
     static_assert((!std::is_convertible<std::shared_ptr<B>, std::shared_ptr<A> >::value), "");
@@ -93,4 +93,6 @@ int main()
     }
     assert(B::count == 0);
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/shared_ptr_Y_rv.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/shared_ptr_Y_rv.pass.cpp
index 8d3af186e50ee69c60cf9d7f64ea6224aa9b8817..cc86d12dfcf5c2b9f887b884a8175089e8046b7c 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/shared_ptr_Y_rv.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/shared_ptr_Y_rv.pass.cpp
@@ -54,7 +54,7 @@ struct C
 
 int C::count = 0;
 
-int main()
+int main(int, char**)
 {
     static_assert(( std::is_convertible<std::shared_ptr<A>, std::shared_ptr<B> >::value), "");
     static_assert((!std::is_convertible<std::shared_ptr<B>, std::shared_ptr<A> >::value), "");
@@ -109,4 +109,6 @@ int main()
     }
     assert(B::count == 0);
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/shared_ptr_pointer.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/shared_ptr_pointer.pass.cpp
index 06a285cd2ced1aaca02bfabe990cce517873f974..83a9a9720dc415864b2ed6aa91ea3bf89648ed15 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/shared_ptr_pointer.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/shared_ptr_pointer.pass.cpp
@@ -37,7 +37,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::shared_ptr<A> pA(new A);
@@ -57,4 +57,6 @@ int main()
     }
     assert(A::count == 0);
     assert(B::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/shared_ptr_rv.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/shared_ptr_rv.pass.cpp
index d9eef4a23887793e28ea3b0320507c5d6c4e139e..86797a047e8c0dcbfdabad2dee238e1cd5acb866 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/shared_ptr_rv.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/shared_ptr_rv.pass.cpp
@@ -30,7 +30,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::shared_ptr<A> pA(new A);
@@ -73,4 +73,6 @@ int main()
         assert(A::count == 0);
     }
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/unique_ptr.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/unique_ptr.pass.cpp
index d235a50b9a15c1f033b527ac63e8b9b8e8de39c0..6fd812fca0a060728066092c2aeb9bab82d6284f 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/unique_ptr.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/unique_ptr.pass.cpp
@@ -49,7 +49,7 @@ void fn ( const std::shared_ptr<B> &) { assert (false); }
 template <typename T>
 void assert_deleter ( T * ) { assert(false); }
 
-int main()
+int main(int, char**)
 {
     {
         std::unique_ptr<A> ptr(new A);
@@ -97,4 +97,6 @@ int main()
         std::shared_ptr<int> p2(std::move(p)); // should not call deleter when going out of scope
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/weak_ptr.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/weak_ptr.pass.cpp
index 117a74aaa57b01b04b6082e4b28c00f8b6495580..9174f39be37bd40543df99e88a025c5baf317063 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/weak_ptr.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.const/weak_ptr.pass.cpp
@@ -40,7 +40,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
 #ifndef TEST_HAS_NO_EXCEPTIONS
     {
@@ -81,4 +81,6 @@ int main()
     }
     assert(A::count == 0);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.create/allocate_shared.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.create/allocate_shared.pass.cpp
index 354a23e7015e865e71117bb1b8161e3d4130eedf..06c2bba6705a81ef4f7c5eb9937e520beba7c45d 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.create/allocate_shared.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.create/allocate_shared.pass.cpp
@@ -51,7 +51,7 @@ private:
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
     int i = 67;
@@ -82,4 +82,6 @@ int main()
     assert(p->get_char() == 'f');
     }
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.create/allocate_shared_cxx03.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.create/allocate_shared_cxx03.pass.cpp
index 0783b6e7f1cc8503da06f79240a1f70628ab4044..00f79cc19d2c5324a27aec4c2b311399651e947e 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.create/allocate_shared_cxx03.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.create/allocate_shared_cxx03.pass.cpp
@@ -97,7 +97,7 @@ void test()
     assert(Three::count == 0);
 }
 
-int main()
+int main(int, char**)
 {
     {
     int i = 67;
@@ -114,4 +114,6 @@ int main()
 #if TEST_STD_VER >= 11
     test<min_allocator<void> >();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.create/make_shared.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.create/make_shared.pass.cpp
index 2535519b9e7af214930f9ce693c7c1060d06db06..aed060e5790eb7c532cddd2c761b25c835aabad3 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.create/make_shared.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.create/make_shared.pass.cpp
@@ -73,7 +73,7 @@ void test_pointer_to_function() {
 void test_pointer_to_function() {}
 #endif // _LIBCPP_VERSION
 
-int main()
+int main(int, char**)
 {
     int nc = globalMemCounter.outstanding_new;
     {
@@ -107,4 +107,6 @@ int main()
     }
 #endif
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.create/make_shared.private.fail.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.create/make_shared.private.fail.cpp
index fd5ebdccab39d987ef847652a21ad651820a4fbb..e17d7424be44461013c885cff2e278fc9c8d98bb 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.create/make_shared.private.fail.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.create/make_shared.private.fail.cpp
@@ -22,7 +22,9 @@ private:
    S () {};  // ctor is private
 };
 
-int main()
+int main(int, char**)
 {
     std::shared_ptr<S> p = std::make_shared<S>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.create/make_shared.protected.fail.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.create/make_shared.protected.fail.cpp
index 8ba4a69c3c4645628adb86c4ecbf8b5d249755e3..d4d8fb630c99e0c0bc4c8c2502bc496cbf5896c6 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.create/make_shared.protected.fail.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.create/make_shared.protected.fail.cpp
@@ -22,7 +22,9 @@ protected:
    S () {};  // ctor is protected
 };
 
-int main()
+int main(int, char**)
 {
     std::shared_ptr<S> p = std::make_shared<S>();  // expected-error-re@memory:* {{static_assert failed{{.*}} "Can't construct object in make_shared"}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.create/make_shared.volatile.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.create/make_shared.volatile.pass.cpp
index c50b68f70975cf70560ca9824956595c9b6048fe..aa038f7475f8317d119db66f7bca0421d9391fe0 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.create/make_shared.volatile.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.create/make_shared.volatile.pass.cpp
@@ -52,9 +52,11 @@ void test(const T &t0)
 
 }
 
-int main()
+int main(int, char**)
 {
     test<bool>(true);
     test<int>(3);
     test<double>(5.0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.dest/tested_elsewhere.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.dest/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.dest/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.dest/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.io/io.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.io/io.pass.cpp
index cf3aac86aec4f2b0e231f3600e99cb308762d536..b09550a6eab2760c97c9d27a8f33926aae8543a4 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.io/io.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.io/io.pass.cpp
@@ -18,11 +18,13 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::shared_ptr<int> p(new int(3));
     std::ostringstream os;
     assert(os.str().empty());
     os << p;
     assert(!os.str().empty());
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.mod/reset.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.mod/reset.pass.cpp
index 3943b5892ba0f2ae240e81e0e0424f560c46dcba..c9df003192b91379d0263daf6bc71e30387d4828 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.mod/reset.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.mod/reset.pass.cpp
@@ -38,7 +38,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::shared_ptr<B> p(new B);
@@ -58,4 +58,6 @@ int main()
         assert(p.get() == 0);
     }
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.mod/reset_pointer.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.mod/reset_pointer.pass.cpp
index 3e91fa3de5681aa1e1e03a4f37a0e9cf6c818a94..c3582416584a0994eb3b4237e064cc068720f854 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.mod/reset_pointer.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.mod/reset_pointer.pass.cpp
@@ -38,7 +38,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::shared_ptr<B> p(new B);
@@ -60,4 +60,6 @@ int main()
         assert(p.get() == ptr);
     }
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.mod/reset_pointer_deleter.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.mod/reset_pointer_deleter.pass.cpp
index 70a2024cce298f95dae50e87c6069e33f32fdb93..e7d457fa13988f3216f3b6a1ad444c84fd464ab0 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.mod/reset_pointer_deleter.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.mod/reset_pointer_deleter.pass.cpp
@@ -39,7 +39,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::shared_ptr<B> p(new B);
@@ -75,4 +75,6 @@ int main()
     assert(A::count == 0);
     assert(test_deleter<A>::count == 0);
     assert(test_deleter<A>::dealloc_count == 2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.mod/reset_pointer_deleter_allocator.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.mod/reset_pointer_deleter_allocator.pass.cpp
index d4db96826e36d988108b0de9908ebcb26d6f3132..9e2bd1012900ff176515592db2c5b926c8befd30 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.mod/reset_pointer_deleter_allocator.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.mod/reset_pointer_deleter_allocator.pass.cpp
@@ -40,7 +40,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::shared_ptr<B> p(new B);
@@ -84,4 +84,6 @@ int main()
     assert(test_deleter<A>::dealloc_count == 2);
     assert(test_allocator<A>::count == 0);
     assert(test_allocator<A>::alloc_count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.mod/swap.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.mod/swap.pass.cpp
index a47e67f04a983295c87ab184f7e6ed458d04e847..a27949ebb80390454eae4c4f6338d6c21b96d0dd 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.mod/swap.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.mod/swap.pass.cpp
@@ -26,7 +26,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         A* ptr1 = new A;
@@ -100,4 +100,6 @@ int main()
         assert(A::count == 0);
     }
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.obs/arrow.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.obs/arrow.pass.cpp
index 5f7d6582b6f0743e2fc38d148593172e21da2f55..77bf3a22e08065c635eb6ce159c95abbc211a60e 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.obs/arrow.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.obs/arrow.pass.cpp
@@ -16,7 +16,7 @@
 #include <utility>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::shared_ptr<std::pair<int, int> > p(new std::pair<int, int>(3, 4));
     assert(p->first == 3);
@@ -25,4 +25,6 @@ int main()
     p->second = 6;
     assert(p->first == 5);
     assert(p->second == 6);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.obs/dereference.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.obs/dereference.pass.cpp
index 4b2a495a89b8ce404c673273fa8578ff4dd79ef8..a6f75533acb9cfd4ae135ba0680a83e6acf9af54 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.obs/dereference.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.obs/dereference.pass.cpp
@@ -15,10 +15,12 @@
 #include <memory>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::shared_ptr<int> p(new int(32));
     assert(*p == 32);
     *p = 3;
     assert(*p == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.obs/op_bool.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.obs/op_bool.pass.cpp
index 4c6790f867c96df986d89fc34814caaf11190bba..247deb07bb99af5d7d46d05beef8a3278933ab4f 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.obs/op_bool.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.obs/op_bool.pass.cpp
@@ -15,7 +15,7 @@
 #include <memory>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
     const std::shared_ptr<int> p(new int(32));
@@ -25,4 +25,6 @@ int main()
     const std::shared_ptr<int> p;
     assert(!p);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.obs/owner_before_shared_ptr.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.obs/owner_before_shared_ptr.pass.cpp
index c6ae19911c3266b1b7a0bd0ec305c5b51a022276..497a53b214439ffc9920db29276e62aebe6cf410 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.obs/owner_before_shared_ptr.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.obs/owner_before_shared_ptr.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     const std::shared_ptr<int> p1(new int);
     const std::shared_ptr<int> p2 = p1;
@@ -26,4 +26,6 @@ int main()
     assert(p1.owner_before(p3) || p3.owner_before(p1));
     assert(p3.owner_before(p1) == p3.owner_before(p2));
     ASSERT_NOEXCEPT(p1.owner_before(p2));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.obs/owner_before_weak_ptr.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.obs/owner_before_weak_ptr.pass.cpp
index e857aa6a83d3e721404d76008fc3a6c33b0ecfb3..07c7a064420499f41b26622cfc9f8cce89c69dbe 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.obs/owner_before_weak_ptr.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.obs/owner_before_weak_ptr.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     const std::shared_ptr<int> p1(new int);
     const std::shared_ptr<int> p2 = p1;
@@ -29,4 +29,6 @@ int main()
     assert(p1.owner_before(w3) || p3.owner_before(w1));
     assert(p3.owner_before(w1) == p3.owner_before(w2));
     ASSERT_NOEXCEPT(p1.owner_before(w2));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.obs/unique.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.obs/unique.pass.cpp
index 14a2fe992f193dcd3eae49cd812dab47067531ff..dfad31385173ce4e05f1bdda435badc0b61ea9cd 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.obs/unique.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.obs/unique.pass.cpp
@@ -15,7 +15,7 @@
 #include <memory>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::shared_ptr<int> p(new int(32));
     assert(p.unique());
@@ -24,4 +24,6 @@ int main()
     assert(!p.unique());
     }
     assert(p.unique());
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.spec/swap.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.spec/swap.pass.cpp
index b40e4705acfe37470d70dcaf20dee19aa6cf1af3..b0bfcae9ae4cfdac97ca7625436f2cd57318594e 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.spec/swap.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.spec/swap.pass.cpp
@@ -27,7 +27,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         A* ptr1 = new A;
@@ -101,4 +101,6 @@ int main()
         assert(A::count == 0);
     }
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/types.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/types.pass.cpp
index 2263eb810cbd34541a779f96060f629623b7ad67..f5bdb876b466ec292a8a4352e6ea3b1e04f42d80 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/types.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/types.pass.cpp
@@ -19,7 +19,9 @@
 
 struct A;  // purposefully incomplete
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::weak_ptr<A>::element_type, A>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.ownerless/owner_less.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.ownerless/owner_less.pass.cpp
index c65755d8ea42c83b2c6be1fc74930b28f1f5a253..b3cc13d72a895939538fd1a45a1a439596d20b86 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.ownerless/owner_less.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.ownerless/owner_less.pass.cpp
@@ -52,7 +52,7 @@
 
 struct X {};
 
-int main()
+int main(int, char**)
 {
     const std::shared_ptr<int> p1(new int);
     const std::shared_ptr<int> p2 = p1;
@@ -128,4 +128,6 @@ int main()
     assert(s.find(vp) == s.end());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.assign/shared_ptr_Y.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.assign/shared_ptr_Y.pass.cpp
index 1362537e0307812683211b5a82706d46b2056d0c..02f180d3d643139397a2807d773160014631b40d 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.assign/shared_ptr_Y.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.assign/shared_ptr_Y.pass.cpp
@@ -39,7 +39,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         const std::shared_ptr<A> pA(new A);
@@ -57,4 +57,6 @@ int main()
     }
     assert(B::count == 0);
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.assign/weak_ptr.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.assign/weak_ptr.pass.cpp
index 739165c3cab7d320824f72a6590e3ec76f5a428f..f41c391c4c24ccc29715a8a15f7b96c75ffdc5ec 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.assign/weak_ptr.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.assign/weak_ptr.pass.cpp
@@ -39,7 +39,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         const std::shared_ptr<A> ps(new A);
@@ -74,4 +74,6 @@ int main()
     }
     assert(B::count == 0);
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.assign/weak_ptr_Y.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.assign/weak_ptr_Y.pass.cpp
index f763dc463955921c12a44fb17abd85860d496d51..33b2ddd422affa9bd1beba906f11f8e4d1ffdada 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.assign/weak_ptr_Y.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.assign/weak_ptr_Y.pass.cpp
@@ -39,7 +39,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         const std::shared_ptr<A> ps(new A);
@@ -74,4 +74,6 @@ int main()
     }
     assert(B::count == 0);
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.const/default.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.const/default.pass.cpp
index b29623f296ab0092369347f3778d408ec3440443..e5a70abe417d5778942fd7951042b0239c793a4a 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.const/default.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.const/default.pass.cpp
@@ -17,8 +17,10 @@
 
 struct A;
 
-int main()
+int main(int, char**)
 {
     std::weak_ptr<A> p;
     assert(p.use_count() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.const/shared_ptr_Y.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.const/shared_ptr_Y.pass.cpp
index 8aaeab0c9049a7e68e0eed7e2325625ddcda1dbd..45be55e66f8e1da8283193938367d7f07b54a020 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.const/shared_ptr_Y.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.const/shared_ptr_Y.pass.cpp
@@ -50,7 +50,7 @@ struct C
 
 int C::count = 0;
 
-int main()
+int main(int, char**)
 {
     static_assert(( std::is_convertible<std::shared_ptr<A>, std::weak_ptr<B> >::value), "");
     static_assert((!std::is_convertible<std::weak_ptr<B>, std::shared_ptr<A> >::value), "");
@@ -91,4 +91,6 @@ int main()
     }
     assert(B::count == 0);
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.const/weak_ptr.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.const/weak_ptr.pass.cpp
index 351b66323db3b54c92d8bb30bfc1a397f8479823..658b233c41c7b1566e81d978ee2ff353bc7bd19b 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.const/weak_ptr.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.const/weak_ptr.pass.cpp
@@ -61,7 +61,7 @@ template <class T>
 void sink (std::weak_ptr<T> &&) {}
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         const std::shared_ptr<A> ps(new A);
@@ -112,4 +112,6 @@ int main()
     assert(B::count == 0);
     assert(A::count == 0);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.const/weak_ptr_Y.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.const/weak_ptr_Y.pass.cpp
index e155e4faa1354cacdb81296e00e17f1bc83d6268..4268fda3aba42f283ce1c023b8a50ddaea026f11 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.const/weak_ptr_Y.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.const/weak_ptr_Y.pass.cpp
@@ -54,7 +54,7 @@ int C::count = 0;
 template <class T>
 std::weak_ptr<T> source (std::shared_ptr<T> p) { return std::weak_ptr<T>(p); }
 
-int main()
+int main(int, char**)
 {
     static_assert(( std::is_convertible<std::weak_ptr<A>, std::weak_ptr<B> >::value), "");
     static_assert((!std::is_convertible<std::weak_ptr<B>, std::weak_ptr<A> >::value), "");
@@ -104,4 +104,6 @@ int main()
     }
     assert(B::count == 0);
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.dest/tested_elsewhere.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.dest/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.dest/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.dest/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.mod/reset.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.mod/reset.pass.cpp
index 7c3bcb6c641c352daeac24f05c12f6fcb168dc51..eae249ca1a53427e0e3916987c081fb8b40bae30 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.mod/reset.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.mod/reset.pass.cpp
@@ -26,7 +26,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::shared_ptr<A> p1(new A);
@@ -37,4 +37,6 @@ int main()
         assert(p1.use_count() == 1);
     }
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.mod/swap.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.mod/swap.pass.cpp
index 38b1dee093af71fad9c6decd473451087598c73b..76703d0ddd755ea43612999fd1e02c8563b7c9fd 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.mod/swap.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.mod/swap.pass.cpp
@@ -26,7 +26,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         A* ptr1 = new A;
@@ -45,4 +45,6 @@ int main()
         }
     }
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.obs/expired.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.obs/expired.pass.cpp
index f2fccb5589da9cff5b12fe94c0f9238fba38eac7..5fb2dd4f95bf2eac206df561677a557fef817f74 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.obs/expired.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.obs/expired.pass.cpp
@@ -26,7 +26,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::weak_ptr<A> wp;
@@ -42,4 +42,6 @@ int main()
         assert(wp.use_count() == 0);
         assert(wp.expired() == (wp.use_count() == 0));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.obs/lock.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.obs/lock.pass.cpp
index 883de740cce20737852da0c5ec966d1550e2c806..50ff84318efcf9d9d931f9f301792719f682c1c5 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.obs/lock.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.obs/lock.pass.cpp
@@ -26,7 +26,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::weak_ptr<A> wp;
@@ -54,4 +54,6 @@ int main()
         assert(A::count == 0);
     }
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.obs/not_less_than.fail.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.obs/not_less_than.fail.cpp
index c916a8907402baa015743be4a57393e644f67d68..2df6d6a0e322a8ae519325c0b3c30265c4fd5428 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.obs/not_less_than.fail.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.obs/not_less_than.fail.cpp
@@ -15,7 +15,7 @@
 #include <memory>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::shared_ptr<int> p1(new int);
     const std::shared_ptr<int> p2(new int);
@@ -23,4 +23,6 @@ int main()
     const std::weak_ptr<int> w2(p2);
 
     bool b = w1 < w2;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.obs/owner_before_shared_ptr.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.obs/owner_before_shared_ptr.pass.cpp
index d8483d9b65ea37c1c2814ffc1d729751b9cf9b0e..4d26f5f2b33255e0cdd43d33c009340cce3ffb85 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.obs/owner_before_shared_ptr.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.obs/owner_before_shared_ptr.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     const std::shared_ptr<int> p1(new int);
     const std::shared_ptr<int> p2 = p1;
@@ -29,4 +29,6 @@ int main()
     assert(w1.owner_before(p3) || w3.owner_before(p1));
     assert(w3.owner_before(p1) == w3.owner_before(p2));
     ASSERT_NOEXCEPT(w1.owner_before(p2));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.obs/owner_before_weak_ptr.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.obs/owner_before_weak_ptr.pass.cpp
index b323da7d50349645939f430ed826147a7b872246..39993cd8f6a6ce1fcf156b44fa8fa4047ee90ca4 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.obs/owner_before_weak_ptr.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.obs/owner_before_weak_ptr.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     const std::shared_ptr<int> p1(new int);
     const std::shared_ptr<int> p2 = p1;
@@ -29,4 +29,6 @@ int main()
     assert(w1.owner_before(w3) || w3.owner_before(w1));
     assert(w3.owner_before(w1) == w3.owner_before(w2));
     ASSERT_NOEXCEPT(w1.owner_before(w2));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.spec/swap.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.spec/swap.pass.cpp
index e13d5aeaf63673a96731938b730ca790384b188a..53bc3eb9cd86a1b41ac41a39090cc8801ddd1e9c 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.spec/swap.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weak/util.smartptr.weak.spec/swap.pass.cpp
@@ -27,7 +27,7 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         A* ptr1 = new A;
@@ -46,4 +46,6 @@ int main()
         }
     }
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weakptr/bad_weak_ptr.pass.cpp b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weakptr/bad_weak_ptr.pass.cpp
index a85120ae05f742ee1614444e957db5c369d14aef..f3e26dee54e8343280fc85205d83a2bf01edc2ee 100644
--- a/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weakptr/bad_weak_ptr.pass.cpp
+++ b/libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.weakptr/bad_weak_ptr.pass.cpp
@@ -20,11 +20,13 @@
 #include <cassert>
 #include <cstring>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::exception, std::bad_weak_ptr>::value), "");
     std::bad_weak_ptr e;
     std::bad_weak_ptr e2 = e;
     e2 = e;
     assert(std::strcmp(e.what(), "bad_weak_ptr") == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.help/bool_constant.pass.cpp b/libcxx/test/std/utilities/meta/meta.help/bool_constant.pass.cpp
index b9037f527041288e6be411984efdb041ebc5f79a..917f8b919fa988f6dba32f1ade05e2873fc22696 100644
--- a/libcxx/test/std/utilities/meta/meta.help/bool_constant.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.help/bool_constant.pass.cpp
@@ -15,7 +15,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 #if TEST_STD_VER > 14
     typedef std::bool_constant<true> _t;
@@ -30,4 +30,6 @@ int main()
     static_assert((std::is_same<_f::type, _f>::value), "");
     static_assert((_f() == false), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.help/integral_constant.pass.cpp b/libcxx/test/std/utilities/meta/meta.help/integral_constant.pass.cpp
index 89d648750955b011cd9c73696c2445c0ebe22548..f312acad657683d5c0043e66ae60ac5e84a6763a 100644
--- a/libcxx/test/std/utilities/meta/meta.help/integral_constant.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.help/integral_constant.pass.cpp
@@ -15,7 +15,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::integral_constant<int, 5> _5;
     static_assert(_5::value == 5, "");
@@ -47,4 +47,6 @@ int main()
     std::true_type t1;
     std::true_type t2 = t1;
     assert(t2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.logical/conjunction.pass.cpp b/libcxx/test/std/utilities/meta/meta.logical/conjunction.pass.cpp
index 0b9a036213050ba4c88ccc4d309b7a0dcf29da40..e37769576d2fe0f4902d522010c4dc3adc51a587 100644
--- a/libcxx/test/std/utilities/meta/meta.logical/conjunction.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.logical/conjunction.pass.cpp
@@ -19,7 +19,7 @@
 struct True  { static constexpr bool value = true; };
 struct False { static constexpr bool value = false; };
 
-int main()
+int main(int, char**)
 {
     static_assert ( std::conjunction<>::value, "" );
     static_assert ( std::conjunction<std::true_type >::value, "" );
@@ -62,4 +62,6 @@ int main()
 
     static_assert ( std::conjunction_v<True >, "" );
     static_assert (!std::conjunction_v<False>, "" );
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.logical/disjunction.pass.cpp b/libcxx/test/std/utilities/meta/meta.logical/disjunction.pass.cpp
index 00a1b306d61a20b6edd9945aaea18341b41d87c8..baaed6f03ceea74a3de405c490cdac404bdc4b8a 100644
--- a/libcxx/test/std/utilities/meta/meta.logical/disjunction.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.logical/disjunction.pass.cpp
@@ -19,7 +19,7 @@
 struct True  { static constexpr bool value = true; };
 struct False { static constexpr bool value = false; };
 
-int main()
+int main(int, char**)
 {
     static_assert (!std::disjunction<>::value, "" );
     static_assert ( std::disjunction<std::true_type >::value, "" );
@@ -62,4 +62,6 @@ int main()
 
     static_assert ( std::disjunction_v<True >, "" );
     static_assert (!std::disjunction_v<False>, "" );
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.logical/negation.pass.cpp b/libcxx/test/std/utilities/meta/meta.logical/negation.pass.cpp
index d399a5c84e61a390ae7a533aa26e75d8418e12fe..88ca693d31b39256652613c8a99938353f812401 100644
--- a/libcxx/test/std/utilities/meta/meta.logical/negation.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.logical/negation.pass.cpp
@@ -19,7 +19,7 @@
 struct True  { static constexpr bool value = true; };
 struct False { static constexpr bool value = false; };
 
-int main()
+int main(int, char**)
 {
     static_assert (!std::negation<std::true_type >::value, "" );
     static_assert ( std::negation<std::false_type>::value, "" );
@@ -35,4 +35,6 @@ int main()
 
     static_assert ( std::negation<std::negation<std::true_type >>::value, "" );
     static_assert (!std::negation<std::negation<std::false_type>>::value, "" );
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.rel/is_base_of.pass.cpp b/libcxx/test/std/utilities/meta/meta.rel/is_base_of.pass.cpp
index c2b84b35427fbe4b80a3c391db1fcf31a683ebe6..ec27581a4f99cad20e226942f0958837e40d9451 100644
--- a/libcxx/test/std/utilities/meta/meta.rel/is_base_of.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.rel/is_base_of.pass.cpp
@@ -40,7 +40,7 @@ struct B1 : B {};
 struct B2 : B {};
 struct D : private B1, private B2 {};
 
-int main()
+int main(int, char**)
 {
     test_is_base_of<B, D>();
     test_is_base_of<B1, D>();
@@ -53,4 +53,6 @@ int main()
     test_is_not_base_of<B&, D&>();
     test_is_not_base_of<B[3], D[3]>();
     test_is_not_base_of<int, int>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.rel/is_convertible.pass.cpp b/libcxx/test/std/utilities/meta/meta.rel/is_convertible.pass.cpp
index faffaf6b3d658fe66b539cce69b72cc741e22dfa..b1722b0fcecaef44b5d561b5dbad1277a4dcefbe 100644
--- a/libcxx/test/std/utilities/meta/meta.rel/is_convertible.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.rel/is_convertible.pass.cpp
@@ -60,7 +60,7 @@ class CannotInstantiate {
   enum { X = T::ThisExpressionWillBlowUp };
 };
 
-int main()
+int main(int, char**)
 {
     // void
     test_is_convertible<void,void> ();
@@ -259,4 +259,6 @@ int main()
     // Ensure that CannotInstantiate is not instantiated by is_convertible when it is not needed.
     // For example CannotInstantiate is instatiated as a part of ADL lookup for arguments of type CannotInstantiate*.
     static_assert((std::is_convertible<CannotInstantiate<int>*, CannotInstantiate<int>*>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.rel/is_invocable.pass.cpp b/libcxx/test/std/utilities/meta/meta.rel/is_invocable.pass.cpp
index dab17974bb8a10d125bfa552ddf63debc431d768..fa0c0c82e8ad60075469bfa0c02d8532f2be5394 100644
--- a/libcxx/test/std/utilities/meta/meta.rel/is_invocable.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.rel/is_invocable.pass.cpp
@@ -46,7 +46,7 @@ struct Sink {
   void operator()(Args&&...) const {}
 };
 
-int main() {
+int main(int, char**) {
   using AbominableFunc = void(...) const;
 
   //  Non-callable things
@@ -241,4 +241,5 @@ int main() {
   static_assert(std::is_invocable_r_v<void, Fn>, "");
   static_assert(!std::is_invocable_r_v<int, Fn>, "");
 }
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.rel/is_nothrow_invocable.pass.cpp b/libcxx/test/std/utilities/meta/meta.rel/is_nothrow_invocable.pass.cpp
index f21e99b02d0520449fa6644ec991ac58fe01fcfc..baf64c12f9e7211dbd11c612c02d0f690a0d33e8 100644
--- a/libcxx/test/std/utilities/meta/meta.rel/is_nothrow_invocable.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.rel/is_nothrow_invocable.pass.cpp
@@ -80,7 +80,7 @@ void test_noexcept_function_pointers() {
 #endif
 }
 
-int main() {
+int main(int, char**) {
   using AbominableFunc = void(...) const noexcept;
   //  Non-callable things
   {
@@ -212,4 +212,6 @@ int main() {
     static_assert(!std::is_nothrow_invocable_r_v<int, Fn, int>, "");
   }
   test_noexcept_function_pointers();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.rel/is_same.pass.cpp b/libcxx/test/std/utilities/meta/meta.rel/is_same.pass.cpp
index 63458055008499f8d83eb07c92f6117d007a7b4c..739713bf4c2f24039e6ece31f1864dbf248b2b59 100644
--- a/libcxx/test/std/utilities/meta/meta.rel/is_same.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.rel/is_same.pass.cpp
@@ -56,7 +56,7 @@ public:
     ~Class();
 };
 
-int main()
+int main(int, char**)
 {
     test_is_same<int, int>();
     test_is_same<void, void>();
@@ -69,4 +69,6 @@ int main()
     test_is_not_same<Class, int*>();
     test_is_not_same<int*, int&>();
     test_is_not_same<int&, int>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.rqmts/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/meta/meta.rqmts/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/meta/meta.rqmts/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.rqmts/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.arr/remove_all_extents.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.arr/remove_all_extents.pass.cpp
index 62699fed46eff6e0f376c35f01603691451d5b40..a887d52bbc0bdc01f0b1b49c2b3ec584d53b0043 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.arr/remove_all_extents.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.arr/remove_all_extents.pass.cpp
@@ -25,7 +25,7 @@ void test_remove_all_extents()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test_remove_all_extents<int, int> ();
     test_remove_all_extents<const Enum, const Enum> ();
@@ -39,4 +39,6 @@ int main()
     test_remove_all_extents<const int[2][3], const int> ();
     test_remove_all_extents<int[1][2][3], int> ();
     test_remove_all_extents<const int[1][2][3], const int> ();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.arr/remove_extent.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.arr/remove_extent.pass.cpp
index 1c0f988481745f424672c7923ed938005fbf0598..a0b19d6a64a1d404c4e947fa1508efad163f035f 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.arr/remove_extent.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.arr/remove_extent.pass.cpp
@@ -26,7 +26,7 @@ void test_remove_extent()
 }
 
 
-int main()
+int main(int, char**)
 {
     test_remove_extent<int, int> ();
     test_remove_extent<const Enum, const Enum> ();
@@ -40,4 +40,6 @@ int main()
     test_remove_extent<const int[2][3], const int[3]> ();
     test_remove_extent<int[1][2][3], int[2][3]> ();
     test_remove_extent<const int[1][2][3], const int[2][3]> ();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.cv/add_const.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.cv/add_const.pass.cpp
index c7fb61232b36859017beeefdc8b8eab1470a02e9..edde6565744c6435ab7c62a75af7f492b5ed77e6 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.cv/add_const.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.cv/add_const.pass.cpp
@@ -32,7 +32,7 @@ void test_add_const()
     test_add_const_imp<const volatile T, const volatile T>();
 }
 
-int main()
+int main(int, char**)
 {
     test_add_const<void>();
     test_add_const<int>();
@@ -41,4 +41,6 @@ int main()
     test_add_const<const int&>();
     test_add_const<int*>();
     test_add_const<const int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.cv/add_cv.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.cv/add_cv.pass.cpp
index 0662c9dd400fb832e4503c863921e19eccb9f301..5621bbf4263c1b1beb74f52abaaa48aea36d0eaa 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.cv/add_cv.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.cv/add_cv.pass.cpp
@@ -32,7 +32,7 @@ void test_add_cv()
     test_add_cv_imp<const volatile T, const volatile T>();
 }
 
-int main()
+int main(int, char**)
 {
     test_add_cv<void>();
     test_add_cv<int>();
@@ -41,4 +41,6 @@ int main()
     test_add_cv<const int&>();
     test_add_cv<int*>();
     test_add_cv<const int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.cv/add_volatile.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.cv/add_volatile.pass.cpp
index 476a780a423d6527c815b849c4729526844bd50f..6dfaa60f894c026d182d610d0bb4c18cfd11e638 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.cv/add_volatile.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.cv/add_volatile.pass.cpp
@@ -32,7 +32,7 @@ void test_add_volatile()
     test_add_volatile_imp<const volatile T, const volatile T>();
 }
 
-int main()
+int main(int, char**)
 {
     test_add_volatile<void>();
     test_add_volatile<int>();
@@ -41,4 +41,6 @@ int main()
     test_add_volatile<const int&>();
     test_add_volatile<int*>();
     test_add_volatile<const int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.cv/remove_const.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.cv/remove_const.pass.cpp
index d53d6f805f9b698a5e5ac5575ebf0c88b87f7c1e..3c927e7c92e75a362a2b80e991a25fd2927ef931 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.cv/remove_const.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.cv/remove_const.pass.cpp
@@ -32,7 +32,7 @@ void test_remove_const()
     test_remove_const_imp<const volatile T, volatile T>();
 }
 
-int main()
+int main(int, char**)
 {
     test_remove_const<void>();
     test_remove_const<int>();
@@ -41,4 +41,6 @@ int main()
     test_remove_const<const int&>();
     test_remove_const<int*>();
     test_remove_const<const int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.cv/remove_cv.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.cv/remove_cv.pass.cpp
index 569b9642d35cb7c48b10a302eedaf62d778b1087..2dc8d26e0e39f9f1545d4767cb690d3f6d4d04f0 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.cv/remove_cv.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.cv/remove_cv.pass.cpp
@@ -32,7 +32,7 @@ void test_remove_cv()
     test_remove_cv_imp<const volatile T, T>();
 }
 
-int main()
+int main(int, char**)
 {
     test_remove_cv<void>();
     test_remove_cv<int>();
@@ -41,4 +41,6 @@ int main()
     test_remove_cv<const int&>();
     test_remove_cv<int*>();
     test_remove_cv<const int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.cv/remove_volatile.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.cv/remove_volatile.pass.cpp
index 358d2fa8bfdd53b424e5e3c46c50eb9f947b9f45..fb45d94395e34d9ff034e08e4d0addc582b142bc 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.cv/remove_volatile.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.cv/remove_volatile.pass.cpp
@@ -32,7 +32,7 @@ void test_remove_volatile()
     test_remove_volatile_imp<const volatile T, const T>();
 }
 
-int main()
+int main(int, char**)
 {
     test_remove_volatile<void>();
     test_remove_volatile<int>();
@@ -41,4 +41,6 @@ int main()
     test_remove_volatile<const int&>();
     test_remove_volatile<int*>();
     test_remove_volatile<volatile int*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/aligned_storage.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/aligned_storage.pass.cpp
index 08c0b8bb162f071b279992974d0690315984501e..3e80402e81426a9991134a21b15e23f314d79577 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/aligned_storage.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/aligned_storage.pass.cpp
@@ -17,7 +17,7 @@
 #include <cstddef>       // for std::max_align_t
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::aligned_storage<10, 1 >::type T1;
@@ -285,4 +285,6 @@ int main()
     static_assert(std::alignment_of<T1>::value == 8, "");
     static_assert(sizeof(T1) == 16, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/aligned_union.fail.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/aligned_union.fail.cpp
index 2564f11200510eba58bf48ef95a845ff0f150a29..cf9fe632dd34bc094dddfa7bbf782a5fe7c22279 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/aligned_union.fail.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/aligned_union.fail.cpp
@@ -16,7 +16,9 @@
 
 class A; // Incomplete
 
-int main()
+int main(int, char**)
 {
     typedef std::aligned_union<10, A>::type T1;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/aligned_union.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/aligned_union.pass.cpp
index 800a0074cb9e74fe2a707e3d88fdf96aeb8c9e80..789fd12a9ff5d4638e394c2c5f4fbddc94f2de69 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/aligned_union.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/aligned_union.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::aligned_union<10, char >::type T1;
@@ -111,4 +111,6 @@ int main()
     static_assert(std::alignment_of<T1>::value == 4, "");
     static_assert(sizeof(T1) == 4, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/common_type.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/common_type.pass.cpp
index 70d2ddf095a9e77142f565936bfba0c463cfb508..f96603b30b6b6d7dbbb279bcef4b9fa735d195ce 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/common_type.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/common_type.pass.cpp
@@ -234,7 +234,7 @@ static_assert(is_same<typename result_of<PMD(const S*)>::type, const char&>::val
 } // namespace note_b_example
 #endif // TEST_STD_VER >= 11
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::common_type<int>::type, int>::value), "");
     static_assert((std::is_same<std::common_type<char>::type, char>::value), "");
@@ -307,4 +307,6 @@ int main()
     static_assert((std::is_same<std::common_type<const int, int>::type,       int>::value), "");
     static_assert((std::is_same<std::common_type<int, const int>::type,       int>::value), "");
     static_assert((std::is_same<std::common_type<const int, const int>::type, int>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/conditional.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/conditional.pass.cpp
index b408dfb2c2ceea802a717558c56587736d1873c6..288376ac93c664c125593e7ef62bbbebf66d6198 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/conditional.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/conditional.pass.cpp
@@ -14,7 +14,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::conditional<true, char, int>::type, char>::value), "");
     static_assert((std::is_same<std::conditional<false, char, int>::type, int>::value), "");
@@ -22,4 +22,6 @@ int main()
     static_assert((std::is_same<std::conditional_t<true, char, int>, char>::value), "");
     static_assert((std::is_same<std::conditional_t<false, char, int>, int>::value), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/decay.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/decay.pass.cpp
index a6f85e921b8b17ba6fc499b5cd53a796b89a8e63..94d9720399f7f9044af9e552c40a7855c0330746 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/decay.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/decay.pass.cpp
@@ -23,7 +23,7 @@ void test_decay()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test_decay<void, void>();
     test_decay<int, int>();
@@ -38,4 +38,6 @@ int main()
     test_decay<int(int)  &, int(int)  &>();
     test_decay<int(int) &&, int(int) &&>();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/enable_if.fail.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/enable_if.fail.cpp
index c7b0763e1d8bc543d26246db983b336ef32868b6..c033d1aef2624d70b7a1b87af58c4f1106c8dd21 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/enable_if.fail.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/enable_if.fail.cpp
@@ -12,7 +12,9 @@
 
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     typedef std::enable_if<false>::type A;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/enable_if.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/enable_if.pass.cpp
index bb107d90ad9ef5ecda4f4ea9085e48e564214ca9..c02c6efdb2dc258798d6aff385837555e5f012b9 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/enable_if.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/enable_if.pass.cpp
@@ -14,7 +14,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::enable_if<true>::type, void>::value), "");
     static_assert((std::is_same<std::enable_if<true, int>::type, int>::value), "");
@@ -22,4 +22,6 @@ int main()
     static_assert((std::is_same<std::enable_if_t<true>, void>::value), "");
     static_assert((std::is_same<std::enable_if_t<true, int>, int>::value), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/enable_if2.fail.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/enable_if2.fail.cpp
index 70aa3e2121fac399e1f11a440c75dd86ae89c6d2..79382d35993cb57ba2158f9e28b760453517873e 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/enable_if2.fail.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/enable_if2.fail.cpp
@@ -13,7 +13,9 @@
 
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     typedef std::enable_if_t<false> A;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/remove_cvref.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/remove_cvref.pass.cpp
index e67cab8e4a89184d45e79670859950134331f0f8..e6a01a77ac53c154f189784777a6527fea9dec0e 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/remove_cvref.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/remove_cvref.pass.cpp
@@ -23,7 +23,7 @@ void test_remove_cvref()
     static_assert((std::is_same<         std::remove_cvref_t<T>,     U>::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     test_remove_cvref<void, void>();
     test_remove_cvref<int, int>();
@@ -48,4 +48,6 @@ int main()
     test_remove_cvref<int(int) volatile, int(int) volatile>();
     test_remove_cvref<int(int)  &, int(int)  &>();
     test_remove_cvref<int(int) &&, int(int) &&>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/result_of.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/result_of.pass.cpp
index 313691f32280113103990d75494f6711a4e71963..34dd6d8ea03208ccb6a3aee39704284c425990f1 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/result_of.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/result_of.pass.cpp
@@ -92,7 +92,7 @@ void test_no_result()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     typedef NotDerived ND;
     { // functor object
@@ -366,4 +366,6 @@ int main()
 #endif
     test_no_result<PMD(ND&)>();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/result_of11.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/result_of11.pass.cpp
index 55fef6a406e4bec168ab3dde3606b3d9bb7bea6e..4c020d3da776bb589922031d366067d1beaf9227 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/result_of11.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/result_of11.pass.cpp
@@ -55,7 +55,7 @@ void test_result_of_imp()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef char F::*PMD;
@@ -168,4 +168,6 @@ int main()
     test_result_of_imp<int (F::* (std::unique_ptr<const F> ))       () const, int>();
     }
     test_result_of_imp<decltype(&wat::foo)(wat), void>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/type_identity.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/type_identity.pass.cpp
index 2946e17f55db211c4f2772bd9145fa4f9878bf8d..7e90c3df9c6c7308da40b96286d36d683dee4508 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/type_identity.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/type_identity.pass.cpp
@@ -22,7 +22,7 @@ void test_type_identity()
     static_assert((std::is_same<         std::type_identity_t<T>,     T>::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     test_type_identity<void>();
     test_type_identity<int>();
@@ -36,4 +36,6 @@ int main()
     test_type_identity<int(int) volatile>();
     test_type_identity<int(int)  &>();
     test_type_identity<int(int) &&>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/underlying_type.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/underlying_type.pass.cpp
index ed1bdc44c6928cb8f77c3c566c43010ff88a975a..be1c739ee82974958256981d4d63dee1c0d765dc 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/underlying_type.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/underlying_type.pass.cpp
@@ -27,7 +27,7 @@ enum E { V = INT_MIN };
 enum F { W = UINT_MAX };
 #endif // TEST_UNSIGNED_UNDERLYING_TYPE
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::underlying_type<E>::type, int>::value),
                   "E has the wrong underlying type");
@@ -52,4 +52,6 @@ int main()
     static_assert((std::is_same<std::underlying_type_t<G>, char>::value), "");
 #endif // TEST_STD_VER > 11
 #endif // TEST_STD_VER >= 11
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.ptr/add_pointer.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.ptr/add_pointer.pass.cpp
index ec4e270be4770180010452c0eb9391ffadbd53dc..22c0b79d6f2ef61a7c7d2489a1cb69ad2ad6aa88 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.ptr/add_pointer.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.ptr/add_pointer.pass.cpp
@@ -45,7 +45,7 @@ void test_function1()
 
 struct Foo {};
 
-int main()
+int main(int, char**)
 {
     test_add_pointer<void, void*>();
     test_add_pointer<int, int*>();
@@ -76,4 +76,6 @@ int main()
     test_function0<void (Foo::*)() const &>();
     test_function0<void (Foo::*)() const &&>();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.ptr/remove_pointer.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.ptr/remove_pointer.pass.cpp
index 1f62b141251a27aeed6bd722e0186c516373375f..ba7cceb2968dff335a256d0f1fa9292921748dd2 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.ptr/remove_pointer.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.ptr/remove_pointer.pass.cpp
@@ -22,7 +22,7 @@ void test_remove_pointer()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test_remove_pointer<void, void>();
     test_remove_pointer<int, int>();
@@ -40,4 +40,6 @@ int main()
     test_remove_pointer<int(*)[3], int[3]>();
     test_remove_pointer<int*&, int*&>();
     test_remove_pointer<const int*&, const int*&>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.ref/add_lvalue_ref.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.ref/add_lvalue_ref.pass.cpp
index 68d8aef35e1ac731db39dedc861ce3bcfea9552d..dadcafca6b029daf01593459bb57547d7f268a53 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.ref/add_lvalue_ref.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.ref/add_lvalue_ref.pass.cpp
@@ -44,7 +44,7 @@ void test_function1()
 
 struct Foo {};
 
-int main()
+int main(int, char**)
 {
     test_add_lvalue_reference<void, void>();
     test_add_lvalue_reference<int, int&>();
@@ -75,4 +75,6 @@ int main()
     test_function0<void (Foo::*)() const &>();
     test_function0<void (Foo::*)() const &&>();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.ref/add_rvalue_ref.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.ref/add_rvalue_ref.pass.cpp
index c13a62366312717f978cdf34086594a3a9d9bb6f..34c6cd3dd6ddfbf65c68bd5c7b64b96d6db4937d 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.ref/add_rvalue_ref.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.ref/add_rvalue_ref.pass.cpp
@@ -46,7 +46,7 @@ void test_function1()
 
 struct Foo {};
 
-int main()
+int main(int, char**)
 {
     test_add_rvalue_reference<void, void>();
     test_add_rvalue_reference<int, int&&>();
@@ -73,4 +73,6 @@ int main()
     test_function0<void (Foo::*)() &&>();
     test_function0<void (Foo::*)() const &>();
     test_function0<void (Foo::*)() const &&>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.ref/remove_ref.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.ref/remove_ref.pass.cpp
index 1cecd51e28d953e6de0dd98b60fddd168c6a2023..5612ba678abacf09c0b8cd27e57d6a62314fc5fa 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.ref/remove_ref.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.ref/remove_ref.pass.cpp
@@ -22,7 +22,7 @@ void test_remove_reference()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test_remove_reference<void, void>();
     test_remove_reference<int, int>();
@@ -43,4 +43,6 @@ int main()
     test_remove_reference<int*&&, int*>();
     test_remove_reference<const int*&&, const int*>();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.sign/make_signed.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.sign/make_signed.pass.cpp
index b962782d03d71154ea89ff7db30aafbb1f976c33..fa6ce8e3e4d2dbd8bbb8e898309b3d140ae83101 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.sign/make_signed.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.sign/make_signed.pass.cpp
@@ -42,7 +42,7 @@ void test_make_signed()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test_make_signed< signed char, signed char >();
     test_make_signed< unsigned char, signed char >();
@@ -66,4 +66,6 @@ int main()
     test_make_signed< HugeEnum, __int128_t >();
 # endif
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.sign/make_unsigned.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.sign/make_unsigned.pass.cpp
index 606fdf426a90ef3d32ea2723d7f7bbdcbce922a3..cf5404f8c9003ef256beeebaffa3c1be83a5b039 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.sign/make_unsigned.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.sign/make_unsigned.pass.cpp
@@ -42,7 +42,7 @@ void test_make_unsigned()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test_make_unsigned<signed char, unsigned char> ();
     test_make_unsigned<unsigned char, unsigned char> ();
@@ -67,4 +67,6 @@ int main()
     test_make_unsigned<HugeEnum, __uint128_t>();
 # endif
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/meta/meta.trans/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.type.synop/endian.pass.cpp b/libcxx/test/std/utilities/meta/meta.type.synop/endian.pass.cpp
index 65ba30192612300b43ebcfd864ea0f214b9f54ed..52924b357b8e5d793e9841217c8a0a197b9e8ca8 100644
--- a/libcxx/test/std/utilities/meta/meta.type.synop/endian.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.type.synop/endian.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "test_macros.h"
 
-int main() {
+int main(int, char**) {
     static_assert(std::is_enum<std::endian>::value, "");
 
 // Check that E is a scoped enum by checking for conversions.
@@ -43,4 +43,6 @@ int main() {
 
     assert ((c[0] == 1) == (std::endian::native == std::endian::big));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.type.synop/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/meta/meta.type.synop/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/meta/meta.type.synop/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.type.synop/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary.prop.query/alignment_of.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary.prop.query/alignment_of.pass.cpp
index 903098415beea5ae7fe90ac83851b21f5d7a0a95..43cc5bfcefc350fe8c381e716459f226f0f94628 100644
--- a/libcxx/test/std/utilities/meta/meta.unary.prop.query/alignment_of.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary.prop.query/alignment_of.pass.cpp
@@ -39,7 +39,7 @@ public:
     ~Class();
 };
 
-int main()
+int main(int, char**)
 {
     test_alignment_of<int&, 4>();
     test_alignment_of<Class, 1>();
@@ -57,4 +57,6 @@ int main()
     test_alignment_of<bool, 1>();
 #endif
     test_alignment_of<unsigned, 4>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary.prop.query/extent.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary.prop.query/extent.pass.cpp
index bfd36533ebb00f8e3ca8a2c32783880b8849f2f5..927ce1373cc063ff9870fdd685fe5b2cf2d95f17 100644
--- a/libcxx/test/std/utilities/meta/meta.unary.prop.query/extent.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary.prop.query/extent.pass.cpp
@@ -50,7 +50,7 @@ public:
     ~Class();
 };
 
-int main()
+int main(int, char**)
 {
     test_extent<void, 0>();
     test_extent<int&, 0>();
@@ -70,4 +70,6 @@ int main()
     test_extent1<int[2], 0>();
     test_extent1<int[2][4], 4>();
     test_extent1<int[][4], 4>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary.prop.query/rank.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary.prop.query/rank.pass.cpp
index 74a3637a475adab0809dadf6aaf5bacf783104f8..6c2eecb86db7c4aa836262570187d7369fd4bda2 100644
--- a/libcxx/test/std/utilities/meta/meta.unary.prop.query/rank.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary.prop.query/rank.pass.cpp
@@ -35,7 +35,7 @@ public:
     ~Class();
 };
 
-int main()
+int main(int, char**)
 {
     test_rank<void, 0>();
     test_rank<int&, 0>();
@@ -50,4 +50,6 @@ int main()
     test_rank<char[3], 1>();
     test_rank<char[][3], 2>();
     test_rank<char[][4][3], 3>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary.prop.query/void_t.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary.prop.query/void_t.pass.cpp
index af46f4726fc12c437de9e98f4ae79a017fafa8a7..652eddaa88ad189baed50905b3812a08ba923533 100644
--- a/libcxx/test/std/utilities/meta/meta.unary.prop.query/void_t.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary.prop.query/void_t.pass.cpp
@@ -45,7 +45,7 @@ public:
     ~Class();
 };
 
-int main()
+int main(int, char**)
 {
     static_assert( std::is_same<void, std::void_t<>>::value, "");
 
@@ -64,4 +64,6 @@ int main()
     test2<void *, int&>();
 
     static_assert( std::is_same<void, std::void_t<int, double const &, Class, volatile int[], void>>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary.prop.query/void_t_feature_test_macro.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary.prop.query/void_t_feature_test_macro.pass.cpp
index 25b8d715aed357331eec95a553ae25f6776444a5..90514eaaebf0e71e09af4cca2560a0612964bbb8 100644
--- a/libcxx/test/std/utilities/meta/meta.unary.prop.query/void_t_feature_test_macro.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary.prop.query/void_t_feature_test_macro.pass.cpp
@@ -27,9 +27,11 @@
 # endif
 #endif
 
-int main()
+int main(int, char**)
 {
 #if defined(__cpp_lib_void_t)
   static_assert(std::is_same_v<std::void_t<int>, void>, "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/array.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/array.pass.cpp
index 1e2dc42ae216ea86b6952e571a927e92b6403c9b..9f3d8f558d1138ce4cb1606704dbfac06b7056c0 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/array.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/array.pass.cpp
@@ -48,7 +48,7 @@ typedef const char const_array[3];
 typedef char incomplete_array[];
 struct Incomplete;
 
-int main()
+int main(int, char**)
 {
     test_array<array>();
     test_array<const_array>();
@@ -57,4 +57,6 @@ int main()
 
 //  LWG#2582
     static_assert(!std::is_array<Incomplete>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/class.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/class.pass.cpp
index 93bf9efb42fe81b978d1a69a4a956de4f24b1419..3dd696932bc137d3f2fa1d169a38b55604ec5721 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/class.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/class.pass.cpp
@@ -49,11 +49,13 @@ class Class
 
 struct incomplete_type;
 
-int main()
+int main(int, char**)
 {
     test_class<Class>();
     test_class<incomplete_type>();
 
 //  LWG#2582
     static_assert( std::is_class<incomplete_type>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/enum.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/enum.pass.cpp
index 95f71b68a2e5b1ec5927175bb54f5d2199351ff2..5fa8499303c54319205a0c189dd229f4c739f7b2 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/enum.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/enum.pass.cpp
@@ -46,10 +46,12 @@ void test_enum()
 enum Enum {zero, one};
 struct incomplete_type;
 
-int main()
+int main(int, char**)
 {
     test_enum<Enum>();
 
 //  LWG#2582
     static_assert(!std::is_enum<incomplete_type>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/floating_point.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/floating_point.pass.cpp
index c4cf7153b4406712f070c620de73e6b3771fa823..1f7556c7a01159ca224e65eac43f5473534e35fd 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/floating_point.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/floating_point.pass.cpp
@@ -45,7 +45,7 @@ void test_floating_point()
 
 struct incomplete_type;
 
-int main()
+int main(int, char**)
 {
     test_floating_point<float>();
     test_floating_point<double>();
@@ -53,4 +53,6 @@ int main()
 
 //  LWG#2582
     static_assert(!std::is_floating_point<incomplete_type>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/function.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/function.pass.cpp
index 19ad3e92b84c89d06d39228fb7e18a1f711e0ec9..d7453be469cc8b5b73762c556ec13d9023649aee 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/function.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/function.pass.cpp
@@ -66,7 +66,7 @@ void test()
 
 struct incomplete_type;
 
-int main()
+int main(int, char**)
 {
     TEST_REGULAR( void () );
     TEST_REGULAR( void (int) );
@@ -89,4 +89,6 @@ int main()
 
 //  LWG#2582
     static_assert(!std::is_function<incomplete_type>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/integral.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/integral.pass.cpp
index 74977e4b160a60deb6894ab9d6e1bf2550147217..df66316b9c8ea546f8c82a946674fc0c3411e916 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/integral.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/integral.pass.cpp
@@ -45,7 +45,7 @@ void test_integral()
 
 struct incomplete_type;
 
-int main()
+int main(int, char**)
 {
     test_integral<bool>();
     test_integral<char>();
@@ -67,4 +67,6 @@ int main()
 
 //  LWG#2582
     static_assert(!std::is_integral<incomplete_type>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_array.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_array.pass.cpp
index 8611daa15f16166936c3347901a5313551f0a6f7..3205819911c17b516f9eecb9bd968b580d9b4bc0 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_array.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_array.pass.cpp
@@ -70,7 +70,7 @@ struct incomplete_type;
 
 typedef void (*FunctionPtr)();
 
-int main()
+int main(int, char**)
 {
     test_is_array<char[3]>();
     test_is_array<char[]>();
@@ -90,4 +90,6 @@ int main()
     test_is_not_array<bit_zero>();
     test_is_not_array<NotEmpty>();
     test_is_not_array<incomplete_type>();  //  LWG#2582
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_class.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_class.pass.cpp
index 6eda248f7c5d2c13a8a24af91e77ce253bf4f911..def798b779b15b0fe0c844ddfa493c833aed39e9 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_class.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_class.pass.cpp
@@ -70,7 +70,7 @@ struct incomplete_type;
 
 typedef void (*FunctionPtr)();
 
-int main()
+int main(int, char**)
 {
     test_is_class<Empty>();
     test_is_class<bit_zero>();
@@ -96,4 +96,6 @@ int main()
     test_is_not_class<Enum>();
     test_is_not_class<Union>();
     test_is_not_class<FunctionPtr>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_enum.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_enum.pass.cpp
index 0261581f6bffeac9f3e1401b0331622bc165eafd..7d4b67fd872b5c29003d282d4a2578e2978c0277 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_enum.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_enum.pass.cpp
@@ -70,7 +70,7 @@ struct incomplete_type;
 
 typedef void (*FunctionPtr)();
 
-int main()
+int main(int, char**)
 {
     test_is_enum<Enum>();
 
@@ -91,4 +91,6 @@ int main()
     test_is_not_enum<Abstract>();
     test_is_not_enum<FunctionPtr>();
     test_is_not_enum<incomplete_type>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_floating_point.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_floating_point.pass.cpp
index 78e581a0c4f7ace77aeab2b498abcf78c9105721..e628451dc7d114c8b3bb9cb28fffa9ffdf972b17 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_floating_point.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_floating_point.pass.cpp
@@ -70,7 +70,7 @@ struct incomplete_type;
 
 typedef void (*FunctionPtr)();
 
-int main()
+int main(int, char**)
 {
     test_is_floating_point<float>();
     test_is_floating_point<double>();
@@ -99,4 +99,6 @@ int main()
     test_is_not_floating_point<Enum>();
     test_is_not_floating_point<FunctionPtr>();
     test_is_not_floating_point<incomplete_type>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_function.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_function.pass.cpp
index 0f2304fe7cde41c26e6601a8dbf61d314fb4c3ea..b582499cb8b8821d4ca908b666994702eff685cc 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_function.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_function.pass.cpp
@@ -74,7 +74,7 @@ struct incomplete_type;
 
 typedef void (*FunctionPtr)();
 
-int main()
+int main(int, char**)
 {
     test_is_function<void(void)>();
     test_is_function<int(int)>();
@@ -105,4 +105,6 @@ int main()
   test_is_function<void() noexcept>();
   test_is_function<void() const && noexcept>();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_integral.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_integral.pass.cpp
index ede74445e286e2833c71c5f64fe4e7a208c752fb..216df3b56116aac557f0644a6b52ed7d7d483df9 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_integral.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_integral.pass.cpp
@@ -71,7 +71,7 @@ struct incomplete_type;
 typedef void (*FunctionPtr)();
 
 
-int main()
+int main(int, char**)
 {
     test_is_integral<short>();
     test_is_integral<unsigned short>();
@@ -105,4 +105,6 @@ int main()
     test_is_not_integral<NotEmpty>();
     test_is_not_integral<Abstract>();
     test_is_not_integral<incomplete_type>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_lvalue_reference.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_lvalue_reference.pass.cpp
index fe045a2973536d44fb0639ef7af787b16c7876d7..ed32cd9b999b06c37472a6c2ff2bc909d342b3dd 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_lvalue_reference.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_lvalue_reference.pass.cpp
@@ -72,7 +72,7 @@ struct incomplete_type;
 
 typedef void (*FunctionPtr)();
 
-int main()
+int main(int, char**)
 {
     test_is_lvalue_reference<int&>();
 
@@ -93,4 +93,6 @@ int main()
     test_is_not_lvalue_reference<NotEmpty>();
     test_is_not_lvalue_reference<Abstract>();
     test_is_not_lvalue_reference<incomplete_type>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_member_object_pointer.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_member_object_pointer.pass.cpp
index 7e20b58fc01e7d05e834c3c4f3bf7b934e47722a..95a8b5585788ed7b898a847cc1580eb19fb99796 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_member_object_pointer.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_member_object_pointer.pass.cpp
@@ -71,7 +71,7 @@ struct incomplete_type;
 typedef void (*FunctionPtr)();
 
 
-int main()
+int main(int, char**)
 {
     test_is_member_object_pointer<int Abstract::*>();
     test_is_member_object_pointer<double NotEmpty::*>();
@@ -95,4 +95,6 @@ int main()
     test_is_not_member_object_pointer<NotEmpty>();
     test_is_not_member_object_pointer<Abstract>();
     test_is_not_member_object_pointer<incomplete_type>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_member_pointer.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_member_pointer.pass.cpp
index 0a1b95354f5cd0616e9b382f2c0cc294718f2a84..cf46c7261db3e20a8d396103c06023f1dd09c823 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_member_pointer.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_member_pointer.pass.cpp
@@ -71,7 +71,7 @@ struct incomplete_type;
 typedef void (*FunctionPtr)();
 
 
-int main()
+int main(int, char**)
 {
     test_is_member_pointer<int Abstract::*>();
     test_is_member_pointer<double NotEmpty::*>();
@@ -102,4 +102,6 @@ int main()
   test_is_member_pointer<int (Empty::*)(int, long, long) const noexcept>();
   test_is_member_pointer<int (Empty::*)() & noexcept>();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_null_pointer.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_null_pointer.pass.cpp
index 762c21406d3d04239aa579120a78c9ac26b5a756..7ad765d8bbd0eaaa1dad928de9df8acd923b1841 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_null_pointer.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_null_pointer.pass.cpp
@@ -72,7 +72,7 @@ struct incomplete_type;
 
 typedef void (*FunctionPtr)();
 
-int main()
+int main(int, char**)
 {
     test_is_null_pointer<std::nullptr_t>();
 
@@ -93,4 +93,6 @@ int main()
     test_is_not_null_pointer<NotEmpty>();
     test_is_not_null_pointer<Abstract>();
     test_is_not_null_pointer<incomplete_type>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_pointer.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_pointer.pass.cpp
index 9fa33b93c532c737014576b3928424e770991329..18609b812ea0b60cd639a723db32ad224480c62f 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_pointer.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_pointer.pass.cpp
@@ -70,7 +70,7 @@ struct incomplete_type;
 
 typedef void (*FunctionPtr)();
 
-int main()
+int main(int, char**)
 {
     test_is_pointer<void*>();
     test_is_pointer<int*>();
@@ -92,4 +92,6 @@ int main()
     test_is_not_pointer<NotEmpty>();
     test_is_not_pointer<Abstract>();
     test_is_not_pointer<incomplete_type>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_rvalue_reference.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_rvalue_reference.pass.cpp
index 92e86713cc80ab06ac71edd50d87ba078d2bb3e5..d17ed5feeff6dc5bfcc8ac141f5793a0fc0860f5 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_rvalue_reference.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_rvalue_reference.pass.cpp
@@ -72,7 +72,7 @@ struct incomplete_type;
 
 typedef void (*FunctionPtr)();
 
-int main()
+int main(int, char**)
 {
     test_is_rvalue_reference<int&&>();
 
@@ -93,4 +93,6 @@ int main()
     test_is_not_rvalue_reference<NotEmpty>();
     test_is_not_rvalue_reference<Abstract>();
     test_is_not_rvalue_reference<incomplete_type>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_union.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_union.pass.cpp
index 0fc3c4361fee5dce6326a50774f6fc113d13a907..a86147a9acd2e6512d6ac65f6c7bba27534ef87a 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_union.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_union.pass.cpp
@@ -70,7 +70,7 @@ struct incomplete_type;
 
 typedef void (*FunctionPtr)();
 
-int main()
+int main(int, char**)
 {
     test_is_union<Union>();
 
@@ -91,4 +91,6 @@ int main()
     test_is_not_union<NotEmpty>();
     test_is_not_union<Abstract>();
     test_is_not_union<incomplete_type>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_void.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_void.pass.cpp
index 0bfeaddee83c426b9210501864e1ce90fcbcb23c..ccbca975398570cbb38a9e05ee0886d12e3d0c5f 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_void.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/is_void.pass.cpp
@@ -70,7 +70,7 @@ struct incomplete_type;
 
 typedef void (*FunctionPtr)();
 
-int main()
+int main(int, char**)
 {
     test_is_void<void>();
 
@@ -90,4 +90,6 @@ int main()
     test_is_not_void<Enum>();
     test_is_not_void<FunctionPtr>();
     test_is_not_void<incomplete_type>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/lvalue_ref.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/lvalue_ref.pass.cpp
index b4f010749e859fb4e91017e91bc3705a8fc908a8..1c431edfa5f847ff0828a1d9932aadbc9b9d2a4a 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/lvalue_ref.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/lvalue_ref.pass.cpp
@@ -37,11 +37,13 @@ void test_lvalue_ref()
 
 struct incomplete_type;
 
-int main()
+int main(int, char**)
 {
     test_lvalue_ref<int&>();
     test_lvalue_ref<const int&>();
 
 //  LWG#2582
     static_assert(!std::is_lvalue_reference<incomplete_type>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/member_function_pointer.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/member_function_pointer.pass.cpp
index 345195e0e368aea6a10dbfa095df253f5efee4c4..fdbfd903940157a9c383e30cf76d8d25dd38f560 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/member_function_pointer.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/member_function_pointer.pass.cpp
@@ -52,7 +52,7 @@ class Class
 
 struct incomplete_type;
 
-int main()
+int main(int, char**)
 {
   test_member_function_pointer<void (Class::*)()>();
   test_member_function_pointer<void (Class::*)(int)>();
@@ -225,4 +225,6 @@ int main()
 
 //  LWG#2582
   static_assert(!std::is_member_function_pointer<incomplete_type>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/member_function_pointer_no_variadics.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/member_function_pointer_no_variadics.pass.cpp
index 672a90a6f7686e08967c33e9d0260c1a767ca125..916c580d59120edd14a343e1d4b014f1f326c77a 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/member_function_pointer_no_variadics.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/member_function_pointer_no_variadics.pass.cpp
@@ -51,7 +51,7 @@ class Class
 
 struct incomplete_type;
 
-int main()
+int main(int, char**)
 {
     test_member_function_pointer<void (Class::*)()>();
     test_member_function_pointer<void (Class::*)(int)>();
@@ -79,4 +79,6 @@ int main()
 
 //  LWG#2582
     static_assert(!std::is_member_function_pointer<incomplete_type>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/member_object_pointer.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/member_object_pointer.pass.cpp
index 2f77553fd58f3e9d70532002f098d6d81f6550a0..b22e59e379db99331f10888701ed3db34961736a 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/member_object_pointer.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/member_object_pointer.pass.cpp
@@ -49,10 +49,12 @@ class Class
 
 struct incomplete_type;
 
-int main()
+int main(int, char**)
 {
     test_member_object_pointer<int Class::*>();
 
 //  LWG#2582
     static_assert(!std::is_member_object_pointer<incomplete_type>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/nullptr.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/nullptr.pass.cpp
index 759eee6681a5c7678a520f17643dbdfff051c4b7..993b32fdf01029fab8e88c4572d9448f0896940b 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/nullptr.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/nullptr.pass.cpp
@@ -46,13 +46,16 @@ void test_nullptr()
 
 struct incomplete_type;
 
-int main()
+int main(int, char**)
 {
     test_nullptr<std::nullptr_t>();
 
 //  LWG#2582
     static_assert(!std::is_null_pointer<incomplete_type>::value, "");
+    return 0;
 }
 #else
-int main() {}
+int main(int, char**) {
+  return 0;
+}
 #endif
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/pointer.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/pointer.pass.cpp
index 68964f52616f8d0841e551eb25227d88b7f68d90..68f4186db56025f470f6ab58012217c66ff51e69 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/pointer.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/pointer.pass.cpp
@@ -46,7 +46,7 @@ void test_pointer()
 
 struct incomplete_type;
 
-int main()
+int main(int, char**)
 {
     test_pointer<void*>();
     test_pointer<int*>();
@@ -55,4 +55,6 @@ int main()
 
 //  LWG#2582
     static_assert(!std::is_pointer<incomplete_type>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/rvalue_ref.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/rvalue_ref.pass.cpp
index cf0b246c6a1afe3f4933cb7369182e1fb6256a04..e40a2a0144363a40bed7f10aeb8d7c4e3eaba87c 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/rvalue_ref.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/rvalue_ref.pass.cpp
@@ -38,11 +38,13 @@ void test_rvalue_ref()
 
 struct incomplete_type;
 
-int main()
+int main(int, char**)
 {
     test_rvalue_ref<int&&>();
     test_rvalue_ref<const int&&>();
 
 //  LWG#2582
     static_assert(!std::is_rvalue_reference<incomplete_type>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/union.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/union.pass.cpp
index 683eed65a285c6ccb32ef5aca45a47ab434c83cb..a840f5bb29507da1556b9ca08e90ae72ac516a51 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/union.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/union.pass.cpp
@@ -51,10 +51,12 @@ union Union
 
 struct incomplete_type;
 
-int main()
+int main(int, char**)
 {
     test_union<Union>();
 
 //  LWG#2582
     static_assert(!std::is_union<incomplete_type>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/void.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/void.pass.cpp
index 047de20045bf95d9a72531f68ee12e401b0f6baf..d9defa528be3f5b6342afd4427b9bc4d179192a3 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/void.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.cat/void.pass.cpp
@@ -45,10 +45,12 @@ void test_void()
 
 struct incomplete_type;
 
-int main()
+int main(int, char**)
 {
     test_void<void>();
 
 //  LWG#2582
     static_assert(!std::is_void<incomplete_type>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/array.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/array.pass.cpp
index b0ced4a9ce483a06c0f73067acd780a6e9839b7e..487e14446c32cdc4de7ea9e30bb621318b0ec807 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/array.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/array.pass.cpp
@@ -39,10 +39,12 @@ typedef char incomplete_array[];
 
 class incomplete_type;
 
-int main()
+int main(int, char**)
 {
     test_array<array>();
     test_array<const_array>();
     test_array<incomplete_array>();
     test_array<incomplete_type[]>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/class.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/class.pass.cpp
index bff535c9ade6638434dd6afd1675ba3746d5c392..bc072198f2ebd9855913cbea6568db129e1b4527 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/class.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/class.pass.cpp
@@ -39,8 +39,10 @@ class Class
 
 class incomplete_type;
 
-int main()
+int main(int, char**)
 {
     test_class<Class>();
     test_class<incomplete_type>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/enum.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/enum.pass.cpp
index 33807bc4d0704d784a2176e579cb04983eecd4db..71c74f2ba045b59187bbb65703fbaeea90a56cdb 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/enum.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/enum.pass.cpp
@@ -35,7 +35,9 @@ void test_enum()
 
 enum Enum {zero, one};
 
-int main()
+int main(int, char**)
 {
     test_enum<Enum>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/floating_point.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/floating_point.pass.cpp
index 1a1eaee321c7e45e6ff3d5b7258156723f0397d6..957473c2a91b88e150c4a137e037dcf412cd6abc 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/floating_point.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/floating_point.pass.cpp
@@ -33,9 +33,11 @@ void test_floating_point()
     test_floating_point_imp<const volatile T>();
 }
 
-int main()
+int main(int, char**)
 {
     test_floating_point<float>();
     test_floating_point<double>();
     test_floating_point<long double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/function.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/function.pass.cpp
index 193cf688fe252bba5d80fd8a938242e6ca5f8337..c27b1237ebf905573424f950874659a39212796a 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/function.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/function.pass.cpp
@@ -33,10 +33,12 @@ void test_function()
     test_function_imp<const volatile T>();
 }
 
-int main()
+int main(int, char**)
 {
     test_function<void ()>();
     test_function<void (int)>();
     test_function<int (double)>();
     test_function<int (double, char)>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/integral.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/integral.pass.cpp
index d349b75f7beb180d18a44a8eb677d858972a532b..cac606a516e44177fb73fcfe4fcce662cae1099d 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/integral.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/integral.pass.cpp
@@ -33,7 +33,7 @@ void test_integral()
     test_integral_imp<const volatile T>();
 }
 
-int main()
+int main(int, char**)
 {
     test_integral<bool>();
     test_integral<char>();
@@ -52,4 +52,6 @@ int main()
     test_integral<__int128_t>();
     test_integral<__uint128_t>();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_arithmetic.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_arithmetic.pass.cpp
index ff0ff7a34c82ef1e0ec22fb56006bca6f59fd24d..683e885e288d8cfe0b7d3c46f0bc566786364385 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_arithmetic.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_arithmetic.pass.cpp
@@ -72,7 +72,7 @@ enum Enum {zero, one};
 typedef void (*FunctionPtr)();
 
 
-int main()
+int main(int, char**)
 {
     test_is_arithmetic<short>();
     test_is_arithmetic<unsigned short>();
@@ -103,4 +103,6 @@ int main()
     test_is_not_arithmetic<bit_zero>();
     test_is_not_arithmetic<NotEmpty>();
     test_is_not_arithmetic<Abstract>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_compound.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_compound.pass.cpp
index a0d03dd6e51067f6169ffcc9b4238603d4d3f699..4d789066d6e349b8e1d89719515fbe0ae522f42a 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_compound.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_compound.pass.cpp
@@ -72,7 +72,7 @@ enum Enum {zero, one};
 typedef void (*FunctionPtr)();
 
 
-int main()
+int main(int, char**)
 {
     test_is_compound<char[3]>();
     test_is_compound<char[]>();
@@ -94,4 +94,6 @@ int main()
     test_is_not_compound<void>();
     test_is_not_compound<int>();
     test_is_not_compound<double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_fundamental.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_fundamental.pass.cpp
index 343b1291a0f2085fb43cd02bba51e5373ab3b627..b1a38360297d542e3365b812befb8140ad098fc8 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_fundamental.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_fundamental.pass.cpp
@@ -72,7 +72,7 @@ enum Enum {zero, one};
 typedef void (*FunctionPtr)();
 
 
-int main()
+int main(int, char**)
 {
     test_is_fundamental<std::nullptr_t>();
     test_is_fundamental<void>();
@@ -111,4 +111,6 @@ int main()
     test_is_not_fundamental<Enum>();
     test_is_not_fundamental<NotEmpty>();
     test_is_not_fundamental<Abstract>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_member_pointer.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_member_pointer.pass.cpp
index e5486f73e9e7a2cc38f22f76caf0da7a1fbb4ffa..82f0ae9aa477a987e2435c980b68d683727de165 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_member_pointer.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_member_pointer.pass.cpp
@@ -72,7 +72,7 @@ enum Enum {zero, one};
 typedef void (*FunctionPtr)();
 
 
-int main()
+int main(int, char**)
 {
 //  Arithmetic types (3.9.1), enumeration types, pointer types, pointer to member types (3.9.2),
 //    std::nullptr_t, and cv-qualified versions of these types (3.9.3)
@@ -101,4 +101,6 @@ int main()
     test_is_not_member_pointer<int(int)>();
     test_is_not_member_pointer<Enum>();
     test_is_not_member_pointer<FunctionPtr>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_object.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_object.pass.cpp
index 8ec4a6d0fd93bfb3dbe4a5665ff7aece68de3150..8a6f6d84cfc5d8f98b9535dfada80b0641151b93 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_object.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_object.pass.cpp
@@ -72,7 +72,7 @@ enum Enum {zero, one};
 typedef void (*FunctionPtr)();
 
 
-int main()
+int main(int, char**)
 {
 // An object type is a (possibly cv-qualified) type that is not a function type,
 // not a reference type, and not a void type.
@@ -99,4 +99,6 @@ int main()
     test_is_not_object<int&>();
     test_is_not_object<int&&>();
     test_is_not_object<int(int)>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_reference.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_reference.pass.cpp
index a511daf3522f973f6557a5fc7e73e83ba87862ac..bb8a2d62ca99a187459ad308522010bdccc99cb3 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_reference.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_reference.pass.cpp
@@ -72,7 +72,7 @@ enum Enum {zero, one};
 typedef void (*FunctionPtr)();
 
 
-int main()
+int main(int, char**)
 {
     test_is_reference<int&>();
 #if TEST_STD_VER >= 11
@@ -100,4 +100,6 @@ int main()
     test_is_not_reference<int Empty::*>();
     test_is_not_reference<void (Empty::*)(int)>();
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_scalar.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_scalar.pass.cpp
index c20f1e8ef5a48fb3d62642bda1356bdbc38308f6..804c6848eab1937e51888ad9fe579ee8b2fd1a82 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_scalar.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_scalar.pass.cpp
@@ -72,7 +72,7 @@ enum Enum {zero, one};
 typedef void (*FunctionPtr)();
 
 
-int main()
+int main(int, char**)
 {
 //  Arithmetic types (3.9.1), enumeration types, pointer types, pointer to member types (3.9.2),
 //    std::nullptr_t, and cv-qualified versions of these types (3.9.3)
@@ -110,4 +110,6 @@ int main()
     test_is_not_scalar<NotEmpty>();
     test_is_not_scalar<Abstract>();
     test_is_not_scalar<int(int)>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/lvalue_ref.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/lvalue_ref.pass.cpp
index 0ce0423f646af526184a2fa82c1b327c8227fdb3..44027dadb2648a1adba357ce9b9a6a3a04f2ed20 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/lvalue_ref.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/lvalue_ref.pass.cpp
@@ -24,8 +24,10 @@ void test_lvalue_ref()
     static_assert(!std::is_member_pointer<T>::value, "");
 }
 
-int main()
+int main(int, char**)
 {
     test_lvalue_ref<int&>();
     test_lvalue_ref<const int&>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/member_function_pointer.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/member_function_pointer.pass.cpp
index cc75ef9666adcdf30ca7c249e1fecd1aac0a45ff..fda2e81818a24cf249175cba92d9c42495b4e598 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/member_function_pointer.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/member_function_pointer.pass.cpp
@@ -37,9 +37,11 @@ class Class
 {
 };
 
-int main()
+int main(int, char**)
 {
     test_member_function_pointer<void (Class::*)()>();
     test_member_function_pointer<void (Class::*)(int)>();
     test_member_function_pointer<void (Class::*)(int, char)>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/member_object_pointer.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/member_object_pointer.pass.cpp
index ea130274211f0368df4b8a2b813f457af61f3c0f..3e8117b6a01a47388ddef02c665f6096caf801ee 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/member_object_pointer.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/member_object_pointer.pass.cpp
@@ -37,7 +37,9 @@ class Class
 {
 };
 
-int main()
+int main(int, char**)
 {
     test_member_object_pointer<int Class::*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/pointer.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/pointer.pass.cpp
index 61ae96e5b35f7b87f82a9827f81bccc33168ff3c..f5677b95b679d060372e14eda7111eabaa3192e2 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/pointer.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/pointer.pass.cpp
@@ -33,10 +33,12 @@ void test_pointer()
     test_pointer_imp<const volatile T>();
 }
 
-int main()
+int main(int, char**)
 {
     test_pointer<void*>();
     test_pointer<int*>();
     test_pointer<const int*>();
     test_pointer<void (*)(int)>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/rvalue_ref.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/rvalue_ref.pass.cpp
index 63180a00807dcdddbe178942d5f3724da394fc5e..341b9462692a0bfd22c682b3bed5762e149c525c 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/rvalue_ref.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/rvalue_ref.pass.cpp
@@ -26,8 +26,10 @@ void test_rvalue_ref()
     static_assert(!std::is_member_pointer<T>::value, "");
 }
 
-int main()
+int main(int, char**)
 {
     test_rvalue_ref<int&&>();
     test_rvalue_ref<const int&&>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/union.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/union.pass.cpp
index d30354d1a258ad2560d26f8cf5f087375361beb8..fb48a70f35fd2d8bb905ea8bce4f248b07bb8da1 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/union.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/union.pass.cpp
@@ -39,7 +39,9 @@ union Union
     double __;
 };
 
-int main()
+int main(int, char**)
 {
     test_union<Union>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/void.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/void.pass.cpp
index 3559d7b83116768572ca77a9c1eec7a8e0d89eab..657f72774f49bad89fc2c6ee63d8920a14a39049 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/void.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/void.pass.cpp
@@ -33,7 +33,9 @@ void test_void()
     test_void_imp<const volatile T>();
 }
 
-int main()
+int main(int, char**)
 {
     test_void<void>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/has_unique_object_representations.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/has_unique_object_representations.pass.cpp
index d778526b540efc5cc77ede7171356d38e165ee3a..e6f70123b2c978703414617a50419abb67aaee5c 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/has_unique_object_representations.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/has_unique_object_representations.pass.cpp
@@ -80,7 +80,7 @@ struct B
 };
 
 
-int main()
+int main(int, char**)
 {
     test_has_not_has_unique_object_representations<void>();
     test_has_not_has_unique_object_representations<Empty>();
@@ -102,4 +102,6 @@ int main()
     test_has_unique_object_representations<char[3]>();
     test_has_unique_object_representations<char[]>();
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/has_virtual_destructor.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/has_virtual_destructor.pass.cpp
index 9ee9bf163bae937db6f64c7abe3c634b602ea32e..57c1027c3ba52e529178c86df09dd1c3a1b08e6b 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/has_virtual_destructor.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/has_virtual_destructor.pass.cpp
@@ -70,7 +70,7 @@ struct A
     ~A();
 };
 
-int main()
+int main(int, char**)
 {
     test_has_not_virtual_destructor<void>();
     test_has_not_virtual_destructor<A>();
@@ -87,4 +87,6 @@ int main()
 
     test_has_virtual_destructor<Abstract>();
     test_has_virtual_destructor<NotEmpty>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_abstract.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_abstract.pass.cpp
index cbc0317900d86888f0cb210000c6f08610ec8f96..ee6a12e4bd87ebd42218108740be7c01391f3825 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_abstract.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_abstract.pass.cpp
@@ -72,7 +72,7 @@ struct AbstractTemplate {
 template <>
 struct AbstractTemplate<double> {};
 
-int main()
+int main(int, char**)
 {
     test_is_not_abstract<void>();
     test_is_not_abstract<int&>();
@@ -90,4 +90,6 @@ int main()
     test_is_abstract<Abstract>();
     test_is_abstract<AbstractTemplate<int> >();
     test_is_not_abstract<AbstractTemplate<double> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_aggregate.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_aggregate.pass.cpp
index a8f19fd100eea0c136ba578b4ed6c43723573065..843231f46053f67564fe111b270a380c7799db00 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_aggregate.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_aggregate.pass.cpp
@@ -56,7 +56,7 @@ private:
 struct Union { int x; void* y; };
 
 
-int main ()
+int main(int, char**)
 {
   {
     test_false<void>();
@@ -75,4 +75,6 @@ int main ()
     test_true<Aggregate[42][101]>();
     test_true<Union>();
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_assignable.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_assignable.pass.cpp
index eb98ddb547b5ebf1266e905826ad169803ab96d4..8e5e2cc6e0477bc206f7b6f93ad2a6d4a561c399 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_assignable.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_assignable.pass.cpp
@@ -58,7 +58,7 @@ struct E
 template <typename T>
 struct X { T t; };
 
-int main()
+int main(int, char**)
 {
     test_is_assignable<int&, int&> ();
     test_is_assignable<int&, int> ();
@@ -79,4 +79,6 @@ int main()
 
 //  pointer to incomplete template type
     test_is_assignable<X<D>*&, X<D>*> ();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_const.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_const.pass.cpp
index fdbdfbd596c5a2ccaa2cb00d5c045eda68b1e974..0af73cf7e0c7abe96d34f55837cca48eafb31b2f 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_const.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_const.pass.cpp
@@ -30,7 +30,7 @@ void test_is_const()
 
 struct A; // incomplete
 
-int main()
+int main(int, char**)
 {
     test_is_const<void>();
     test_is_const<int>();
@@ -44,4 +44,6 @@ int main()
 
     static_assert(!std::is_const<int&>::value, "");
     static_assert(!std::is_const<const int&>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_constructible.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_constructible.pass.cpp
index f78319aff8d06a44161e7e2030eaf4da7c9fc7c2..a5b723c0e5970f310387ff4140ee8f6e667e4fb3 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_constructible.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_constructible.pass.cpp
@@ -147,7 +147,7 @@ static constexpr bool clang_disallows_valid_static_cast_bug =
 #endif
 
 
-int main()
+int main(int, char**)
 {
     typedef Base B;
     typedef Derived D;
@@ -301,4 +301,6 @@ int main()
     test_is_not_constructible<void() &&> ();
 #endif
 #endif // TEST_STD_VER >= 11
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_copy_assignable.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_copy_assignable.pass.cpp
index 24719bfb89bc6f3cab996585666aa063855578e3..3f10907a4aaca364148fb95aa7d0b8fe0cbb2486 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_copy_assignable.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_copy_assignable.pass.cpp
@@ -63,7 +63,7 @@ struct C
     void operator=(C&);  // not const
 };
 
-int main()
+int main(int, char**)
 {
     test_is_copy_assignable<int> ();
     test_is_copy_assignable<int&> ();
@@ -81,4 +81,6 @@ int main()
 #endif
     test_is_not_copy_assignable<void> ();
     test_is_not_copy_assignable<C> ();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_copy_constructible.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_copy_constructible.pass.cpp
index 457270a89259a4e14028bdf451c41712a8e0a332..f64c40e862b0b8c2f76e66ec5104d830afbc474b 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_copy_constructible.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_copy_constructible.pass.cpp
@@ -70,7 +70,7 @@ struct C
     void operator=(C&);  // not const
 };
 
-int main()
+int main(int, char**)
 {
     test_is_copy_constructible<A>();
     test_is_copy_constructible<int&>();
@@ -91,4 +91,6 @@ int main()
 #if TEST_STD_VER >= 11
     test_is_not_copy_constructible<B>();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_default_constructible.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_default_constructible.pass.cpp
index aef79f7fab9db966f9b05086569a5f81814a2cc8..ce2ec95618e5ff1dd70b9240175d9cdb74035c14 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_default_constructible.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_default_constructible.pass.cpp
@@ -81,7 +81,7 @@ class B
     B();
 };
 
-int main()
+int main(int, char**)
 {
     test_is_default_constructible<A>();
     test_is_default_constructible<Union>();
@@ -122,4 +122,6 @@ int main()
     test_is_not_default_constructible<void() &&> ();
 #endif
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_destructible.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_destructible.pass.cpp
index 8722b78fe436bbb075ff6cd72fbe1008b64f0263..1a32efa4272095eb71b8c50d92fbab3154d1ae72 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_destructible.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_destructible.pass.cpp
@@ -97,7 +97,7 @@ struct DeletedVirtualPrivateDestructor   { private:   virtual ~DeletedVirtualPri
 #endif
 
 
-int main()
+int main(int, char**)
 {
     test_is_destructible<A>();
     test_is_destructible<int&>();
@@ -142,4 +142,6 @@ int main()
     test_is_not_destructible<NotEmpty>();
 #endif
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_empty.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_empty.pass.cpp
index 6dafb55a3871efeb739824eb99b4c0f4ab705cfe..850af8b7a75a00290243c2f3f30330c00802a171 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_empty.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_empty.pass.cpp
@@ -78,7 +78,7 @@ struct bit_one
     int :  1;
 };
 
-int main()
+int main(int, char**)
 {
     test_is_not_empty<void>();
     test_is_not_empty<int&>();
@@ -100,4 +100,6 @@ int main()
     test_is_empty<EmptyBase>();
     test_is_empty<StaticMember>();
     test_is_empty<bit_zero>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_final.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_final.pass.cpp
index 61aed970ec3eb168d2215f1010969162e863542c..4cded0f928e81798eb18d197655983607cdbab32 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_final.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_final.pass.cpp
@@ -48,7 +48,7 @@ void test_is_not_final()
 #endif
 }
 
-int main ()
+int main(int, char**)
 {
     test_is_not_final<int>();
     test_is_not_final<int*>();
@@ -58,4 +58,6 @@ int main ()
     test_is_not_final<U1*>();
     test_is_final    <U2>();
     test_is_not_final<U2*>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_literal_type.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_literal_type.pass.cpp
index 80bb49509b95397f40f8d8d47c45d0680f999b37..b86ff5a8546567eff546b71e36460db01a001e79 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_literal_type.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_literal_type.pass.cpp
@@ -69,7 +69,7 @@ enum Enum {zero, one};
 
 typedef void (*FunctionPtr)();
 
-int main()
+int main(int, char**)
 {
 #if TEST_STD_VER >= 11
     test_is_literal_type<std::nullptr_t>();
@@ -101,4 +101,6 @@ int main()
 
     test_is_not_literal_type<NotEmpty>();
     test_is_not_literal_type<Abstract>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_move_assignable.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_move_assignable.pass.cpp
index edf825dd716acb46a4df031e5aba01a89c4f004d..5a330c6d34b7706d071d06e938cd6f6108f7d7cf 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_move_assignable.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_move_assignable.pass.cpp
@@ -53,7 +53,7 @@ struct A
     A();
 };
 
-int main()
+int main(int, char**)
 {
     test_is_move_assignable<int> ();
     test_is_move_assignable<A> ();
@@ -68,4 +68,6 @@ int main()
     test_is_not_move_assignable<int[3]> ();
 #endif
     test_is_not_move_assignable<void> ();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_move_constructible.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_move_constructible.pass.cpp
index 3052d3925d7a59b7ba17d9a2a3b594b74cde03b7..06ca5c4630c60969f2be820b8700124c5c9d6a63 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_move_constructible.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_move_constructible.pass.cpp
@@ -66,7 +66,7 @@ struct B
 #endif
 };
 
-int main()
+int main(int, char**)
 {
     test_is_not_move_constructible<char[3]>();
     test_is_not_move_constructible<char[]>();
@@ -84,4 +84,6 @@ int main()
     test_is_move_constructible<NotEmpty>();
     test_is_move_constructible<bit_zero>();
     test_is_move_constructible<B>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_assignable.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_assignable.pass.cpp
index c0a22e3b7a02a530e38297a6a2e6302ee5893f72..be1f016a4eb39e30b0facdb42dee9a23e297dced 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_assignable.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_assignable.pass.cpp
@@ -45,7 +45,7 @@ struct C
     void operator=(C&);  // not const
 };
 
-int main()
+int main(int, char**)
 {
     test_is_nothrow_assignable<int&, int&> ();
     test_is_nothrow_assignable<int&, int> ();
@@ -58,4 +58,6 @@ int main()
     test_is_not_nothrow_assignable<B, A> ();
     test_is_not_nothrow_assignable<A, B> ();
     test_is_not_nothrow_assignable<C, C&> ();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_constructible.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_constructible.pass.cpp
index e9c256acaff373e1f3bb4f2ba1a30b54a4b7ec6d..0d171261a5973c54d0916d4876794807496ac9b3 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_constructible.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_constructible.pass.cpp
@@ -97,7 +97,7 @@ struct Tuple {
 };
 #endif
 
-int main()
+int main(int, char**)
 {
     test_is_nothrow_constructible<int> ();
     test_is_nothrow_constructible<int, const int&> ();
@@ -114,4 +114,6 @@ int main()
     static_assert(!std::is_constructible<Tuple&, Empty>::value, "");
     test_is_not_nothrow_constructible<Tuple &, Empty> (); // See bug #19616.
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_copy_assignable.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_copy_assignable.pass.cpp
index a3d2611c93aeb8418449600285fe92ddc9272f6e..64895adf45c464b973663eef51c2d3de3a887c08 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_copy_assignable.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_copy_assignable.pass.cpp
@@ -52,7 +52,7 @@ struct A
     A& operator=(const A&);
 };
 
-int main()
+int main(int, char**)
 {
     test_has_nothrow_assign<int&>();
     test_has_nothrow_assign<Union>();
@@ -68,4 +68,6 @@ int main()
     test_has_not_nothrow_assign<void>();
     test_has_not_nothrow_assign<A>();
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_copy_constructible.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_copy_constructible.pass.cpp
index 4caaeca259d81ba4f2cddc9fca53fbace12893bd..6b1708839ae2e615809cb26e04a1fcb3e7e983d6 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_copy_constructible.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_copy_constructible.pass.cpp
@@ -55,7 +55,7 @@ struct A
     A(const A&);
 };
 
-int main()
+int main(int, char**)
 {
     test_has_not_nothrow_copy_constructor<void>();
     test_has_not_nothrow_copy_constructor<A>();
@@ -68,4 +68,6 @@ int main()
     test_is_nothrow_copy_constructible<int*>();
     test_is_nothrow_copy_constructible<const int*>();
     test_is_nothrow_copy_constructible<bit_zero>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_default_constructible.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_default_constructible.pass.cpp
index 6e443b303cee252fe32596c9282dd038a164ffbc..c30facc516ba78b03a47a2d365f54b435b79dc2f 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_default_constructible.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_default_constructible.pass.cpp
@@ -67,7 +67,7 @@ struct DThrows
 };
 #endif
 
-int main()
+int main(int, char**)
 {
     test_has_not_nothrow_default_constructor<void>();
     test_has_not_nothrow_default_constructor<int&>();
@@ -84,4 +84,6 @@ int main()
     test_is_nothrow_default_constructible<const int*>();
     test_is_nothrow_default_constructible<char[3]>();
     test_is_nothrow_default_constructible<bit_zero>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_destructible.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_destructible.pass.cpp
index f58a93ce28ac40db5f89f3bf27a8eda0ad2c7daa..817d696d11fd8ef0113e63fabf587028821ba131 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_destructible.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_destructible.pass.cpp
@@ -79,7 +79,7 @@ class Abstract
 };
 
 
-int main()
+int main(int, char**)
 {
     test_is_not_nothrow_destructible<void>();
     test_is_not_nothrow_destructible<char[]>();
@@ -110,4 +110,6 @@ int main()
     test_is_not_nothrow_destructible<PureProtectedDestructor>();
     test_is_not_nothrow_destructible<PurePrivateDestructor>();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_move_assignable.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_move_assignable.pass.cpp
index cb446ef0123e8eaf59fba9dc0af78ce4ee8fac3c..4bcbabbcc4addbbd6334295c12eb700c41cb7097 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_move_assignable.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_move_assignable.pass.cpp
@@ -52,7 +52,7 @@ struct A
     A& operator=(const A&);
 };
 
-int main()
+int main(int, char**)
 {
     test_has_nothrow_assign<int&>();
     test_has_nothrow_assign<Union>();
@@ -66,4 +66,6 @@ int main()
 
     test_has_not_nothrow_assign<void>();
     test_has_not_nothrow_assign<A>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_move_constructible.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_move_constructible.pass.cpp
index ce002e8204c605b4b00159a59bf10976659639c7..ab9e0c6bb4faecdcdb95c71348c17f7ff5d89825 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_move_constructible.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_move_constructible.pass.cpp
@@ -55,7 +55,7 @@ struct A
     A(const A&);
 };
 
-int main()
+int main(int, char**)
 {
     test_has_not_nothrow_move_constructor<void>();
     test_has_not_nothrow_move_constructor<A>();
@@ -68,4 +68,6 @@ int main()
     test_is_nothrow_move_constructible<int*>();
     test_is_nothrow_move_constructible<const int*>();
     test_is_nothrow_move_constructible<bit_zero>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_swappable.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_swappable.pass.cpp
index c90f938c5dcf42af8397b8f2c6de07f58d986e34..f554199c6060ba26920b9ad19127afed3617447f 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_swappable.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_swappable.pass.cpp
@@ -46,7 +46,7 @@ struct ThrowingMove {
 
 } // namespace MyNS
 
-int main()
+int main(int, char**)
 {
     using namespace MyNS;
     {
@@ -79,4 +79,6 @@ int main()
         static_assert(std::is_nothrow_swappable_v<int>, "");
         static_assert(!std::is_nothrow_swappable_v<void>, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_swappable_with.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_swappable_with.pass.cpp
index 2121f75b092d821e22924422786d22828e5c9fb3..fb4beac17c9acc01f80778b4a7a280f36fd3ff6e 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_swappable_with.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_swappable_with.pass.cpp
@@ -45,7 +45,7 @@ void swap(M&&, M&&) noexcept {}
 
 } // namespace MyNS
 
-int main()
+int main(int, char**)
 {
     using namespace MyNS;
     {
@@ -77,4 +77,6 @@ int main()
         static_assert(std::is_nothrow_swappable_with_v<int&, int&>, "");
         static_assert(!std::is_nothrow_swappable_with_v<int&&, int&&>, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_pod.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_pod.pass.cpp
index f0dac244c9bc6040b2858d3c31257c8b4f0285ef..87fe6ebbee8839fc5b793c1ef11bfe87beef2609 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_pod.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_pod.pass.cpp
@@ -49,7 +49,7 @@ public:
     ~Class();
 };
 
-int main()
+int main(int, char**)
 {
     test_is_not_pod<void>();
     test_is_not_pod<int&>();
@@ -61,4 +61,6 @@ int main()
     test_is_pod<const int*>();
     test_is_pod<char[3]>();
     test_is_pod<char[]>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_polymorphic.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_polymorphic.pass.cpp
index feb8f270e52410c4405a5f18749937950e508e34..8829fea6bd73a5e4655a073076c8e5194986e159 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_polymorphic.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_polymorphic.pass.cpp
@@ -72,7 +72,7 @@ class Final {
 };
 #endif
 
-int main()
+int main(int, char**)
 {
     test_is_not_polymorphic<void>();
     test_is_not_polymorphic<int&>();
@@ -91,4 +91,6 @@ int main()
 
     test_is_polymorphic<NotEmpty>();
     test_is_polymorphic<Abstract>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_signed.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_signed.pass.cpp
index 5e9042c797e308a3827f281622933a37c299caa7..4936cc788e250a7781f4eba951864cbacd8eb442 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_signed.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_signed.pass.cpp
@@ -51,7 +51,7 @@ public:
 
 struct A; // incomplete
 
-int main()
+int main(int, char**)
 {
     test_is_not_signed<void>();
     test_is_not_signed<int&>();
@@ -71,4 +71,6 @@ int main()
     test_is_signed<__int128_t>();
     test_is_not_signed<__uint128_t>();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_standard_layout.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_standard_layout.pass.cpp
index 10f23cca988d55e2925477a529b46b86381e7115..fb096c89ad06b0e0eda84f0e352191c365b48240 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_standard_layout.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_standard_layout.pass.cpp
@@ -50,11 +50,13 @@ struct pair
     T2 second;
 };
 
-int main()
+int main(int, char**)
 {
     test_is_standard_layout<int> ();
     test_is_standard_layout<int[3]> ();
     test_is_standard_layout<pair<int, double> > ();
 
     test_is_not_standard_layout<int&> ();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_swappable.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_swappable.pass.cpp
index 3e0980bd5cf212606ea551a64e268b5f3f4aafb7..5768a954d64fff106d03f9848299fd391bba505b 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_swappable.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_swappable.pass.cpp
@@ -63,7 +63,7 @@ void swap(T&, T&) {}
 
 } // end namespace MyNS2
 
-int main()
+int main(int, char**)
 {
     using namespace MyNS;
     {
@@ -94,4 +94,6 @@ int main()
         static_assert(std::is_swappable_v<int>, "");
         static_assert(!std::is_swappable_v<M>, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_swappable_include_order.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_swappable_include_order.pass.cpp
index 5d21f3699b33d2d9c7dbc5e8be3ddfd02a49a95e..5931e7ce7f30f635b7d080455c96afe8a098eb68 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_swappable_include_order.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_swappable_include_order.pass.cpp
@@ -23,7 +23,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     // Use a builtin type so we don't get ADL lookup.
     typedef double T[17][29];
@@ -39,4 +39,6 @@ int main()
        std::iter_swap(t1, t2);
        std::swap_ranges(t1, t1 + 17, t2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_swappable_with.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_swappable_with.pass.cpp
index f11f93338602d99d79a46c94e91784da742f6623..cd65d14efc0d5dc86b552732c381165f697188f3 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_swappable_with.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_swappable_with.pass.cpp
@@ -45,7 +45,7 @@ void swap(M&&, M&&) {}
 
 } // namespace MyNS
 
-int main()
+int main(int, char**)
 {
     using namespace MyNS;
     {
@@ -74,4 +74,6 @@ int main()
         static_assert(std::is_swappable_with_v<int&, int&>, "");
         static_assert(!std::is_swappable_with_v<D&, C&>, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivial.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivial.pass.cpp
index 4350f12997f7a28edb6698ce70634fd180f4b2f7..8bb1b7c9b09dde24d7eab62e22fa273672731903 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivial.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivial.pass.cpp
@@ -51,7 +51,7 @@ public:
     B();
 };
 
-int main()
+int main(int, char**)
 {
     test_is_trivial<int> ();
     test_is_trivial<A> ();
@@ -59,4 +59,6 @@ int main()
     test_is_not_trivial<int&> ();
     test_is_not_trivial<volatile int&> ();
     test_is_not_trivial<B> ();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_assignable.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_assignable.pass.cpp
index a85f57a5e00496212cb0a3552c873146aa0e803c..124480c0755514b6bb91b68564a6f78317a3e76e 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_assignable.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_assignable.pass.cpp
@@ -47,7 +47,7 @@ struct C
     void operator=(C&);  // not const
 };
 
-int main()
+int main(int, char**)
 {
     test_is_trivially_assignable<int&, int&> ();
     test_is_trivially_assignable<int&, int> ();
@@ -58,4 +58,6 @@ int main()
     test_is_not_trivially_assignable<B, A> ();
     test_is_not_trivially_assignable<A, B> ();
     test_is_not_trivially_assignable<C&, C&> ();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_constructible.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_constructible.pass.cpp
index 78ae8cfa99f9a4bd00200a29838fbbdf4879b48f..42d54bd7e25a129463ac8a43d43ee0b2d7bec434 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_constructible.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_constructible.pass.cpp
@@ -65,7 +65,7 @@ struct A
     A(int, double);
 };
 
-int main()
+int main(int, char**)
 {
     test_is_trivially_constructible<int> ();
     test_is_trivially_constructible<int, const int&> ();
@@ -73,4 +73,6 @@ int main()
     test_is_not_trivially_constructible<A, int> ();
     test_is_not_trivially_constructible<A, int, double> ();
     test_is_not_trivially_constructible<A> ();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_copy_assignable.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_copy_assignable.pass.cpp
index 853c8aa32b5d64060ddcf38959d90aab67fc0430..91fbf69f4f29fb9583f7e79b6967af329ab0bd41 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_copy_assignable.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_copy_assignable.pass.cpp
@@ -59,7 +59,7 @@ struct A
     A& operator=(const A&);
 };
 
-int main()
+int main(int, char**)
 {
     test_has_trivially_copy_assignable<int&>();
     test_has_trivially_copy_assignable<Union>();
@@ -76,4 +76,6 @@ int main()
     test_has_not_trivially_copy_assignable<Abstract>();
     test_has_not_trivially_copy_assignable<const Empty>();
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_copy_constructible.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_copy_constructible.pass.cpp
index decd7ffeafa9da480e6cc266c64b4c1d72652752..5744d2ca0e8ff753c014fa4cbbbd23ad2ce76f1e 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_copy_constructible.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_copy_constructible.pass.cpp
@@ -65,7 +65,7 @@ struct A
     A(const A&);
 };
 
-int main()
+int main(int, char**)
 {
     test_has_not_trivial_copy_constructor<void>();
     test_has_not_trivial_copy_constructor<A>();
@@ -80,4 +80,6 @@ int main()
     test_is_trivially_copy_constructible<int*>();
     test_is_trivially_copy_constructible<const int*>();
     test_is_trivially_copy_constructible<bit_zero>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_copyable.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_copyable.pass.cpp
index 073ea681d6ec04d4ed065591f6c9174ef725b301..51ac0803e66e778af37f8e45f545f5b2bbdaebdc 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_copyable.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_copyable.pass.cpp
@@ -65,7 +65,7 @@ public:
     C();
 };
 
-int main()
+int main(int, char**)
 {
     test_is_trivially_copyable<int> ();
     test_is_trivially_copyable<const int> ();
@@ -76,4 +76,6 @@ int main()
     test_is_not_trivially_copyable<int&> ();
     test_is_not_trivially_copyable<const A&> ();
     test_is_not_trivially_copyable<B> ();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_default_constructible.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_default_constructible.pass.cpp
index 2f70ba606a2940751ebba2b4532fc50cc708297c..03ac030a3d7b47e4de1eeb8092a5c9345a659706 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_default_constructible.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_default_constructible.pass.cpp
@@ -69,7 +69,7 @@ struct A
     A();
 };
 
-int main()
+int main(int, char**)
 {
     test_has_not_trivial_default_constructor<void>();
     test_has_not_trivial_default_constructor<int&>();
@@ -85,4 +85,6 @@ int main()
     test_is_trivially_default_constructible<const int*>();
     test_is_trivially_default_constructible<char[3]>();
     test_is_trivially_default_constructible<bit_zero>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_destructible.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_destructible.pass.cpp
index 37ea513fcf2a88cf561b42594310245f93b6c2c8..e79e4926b0d3ba48089317acd71823efb9717d4d 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_destructible.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_destructible.pass.cpp
@@ -87,7 +87,7 @@ struct A
     ~A();
 };
 
-int main()
+int main(int, char**)
 {
     test_is_not_trivially_destructible<void>();
     test_is_not_trivially_destructible<A>();
@@ -115,4 +115,6 @@ int main()
     test_is_not_trivially_destructible<PureProtectedDestructor>();
     test_is_not_trivially_destructible<PurePrivateDestructor>();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_move_assignable.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_move_assignable.pass.cpp
index c4aa7b7dced96d17b355fa9e1fa0491a133b37d4..0a91efdf089e11c572d6b307f92e5cb0a3de1f61 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_move_assignable.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_move_assignable.pass.cpp
@@ -59,7 +59,7 @@ struct A
     A& operator=(const A&);
 };
 
-int main()
+int main(int, char**)
 {
     test_has_trivial_assign<int&>();
     test_has_trivial_assign<Union>();
@@ -76,4 +76,6 @@ int main()
     test_has_not_trivial_assign<Abstract>();
     test_has_not_trivial_assign<const Empty>();
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_move_constructible.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_move_constructible.pass.cpp
index 6f47ed6fd4d4d3784aed9fbe2862cc42fa8da34d..78c10a1320a32b30321954a00b101b968e3edf6d 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_move_constructible.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_trivially_move_constructible.pass.cpp
@@ -75,7 +75,7 @@ struct MoveOnly2
 
 #endif
 
-int main()
+int main(int, char**)
 {
     test_has_not_trivial_move_constructor<void>();
     test_has_not_trivial_move_constructor<A>();
@@ -94,4 +94,6 @@ int main()
     static_assert(!std::is_trivially_move_constructible<MoveOnly1>::value, "");
     static_assert( std::is_trivially_move_constructible<MoveOnly2>::value, "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_unsigned.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_unsigned.pass.cpp
index 86e5611c7b235566ca7e3d955d34c36351535432..bc70a43b9bd505aa6c58931af0d7ea535bfe3135 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_unsigned.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_unsigned.pass.cpp
@@ -51,7 +51,7 @@ public:
 
 struct A; // incomplete
 
-int main()
+int main(int, char**)
 {
     test_is_not_unsigned<void>();
     test_is_not_unsigned<int&>();
@@ -71,4 +71,6 @@ int main()
     test_is_unsigned<__uint128_t>();
     test_is_not_unsigned<__int128_t>();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_volatile.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_volatile.pass.cpp
index 28cb29f3bd96306e68efce1e100a395058ef9cca..cb0fc3c6ea8a2bf3557bea5073926a473806804a 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_volatile.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_volatile.pass.cpp
@@ -30,7 +30,7 @@ void test_is_volatile()
 
 struct A; // incomplete
 
-int main()
+int main(int, char**)
 {
     test_is_volatile<void>();
     test_is_volatile<int>();
@@ -44,4 +44,6 @@ int main()
 
     static_assert(!std::is_volatile<int&>::value, "");
     static_assert(!std::is_volatile<volatile int&>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/meta/meta.unary/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/meta/meta.unary/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/meta/meta.unary/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.unary/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.bad_optional_access/default.pass.cpp b/libcxx/test/std/utilities/optional/optional.bad_optional_access/default.pass.cpp
index cfae639636acf7c72ed44391e70431c11915b41e..9bcfa8e4656f2c1c0074d374f6ada558590c1d4b 100644
--- a/libcxx/test/std/utilities/optional/optional.bad_optional_access/default.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.bad_optional_access/default.pass.cpp
@@ -23,8 +23,10 @@
 #include <optional>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     using std::bad_optional_access;
     bad_optional_access ex;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.bad_optional_access/derive.pass.cpp b/libcxx/test/std/utilities/optional/optional.bad_optional_access/derive.pass.cpp
index 80f2372e45692d18a804426bf3f6f32cefcd7712..ac7be93f709b0e50ecea2befeac08a8e8a25f27c 100644
--- a/libcxx/test/std/utilities/optional/optional.bad_optional_access/derive.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.bad_optional_access/derive.pass.cpp
@@ -23,10 +23,12 @@
 #include <optional>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     using std::bad_optional_access;
 
     static_assert(std::is_base_of<std::exception, bad_optional_access>::value, "");
     static_assert(std::is_convertible<bad_optional_access*, std::exception*>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.comp_with_t/equal.pass.cpp b/libcxx/test/std/utilities/optional/optional.comp_with_t/equal.pass.cpp
index dbf8a0564b50febf3ded2117e771eecd94a62594..4f7aedbcb0f06da2ae912e326c3115afb9c555cd 100644
--- a/libcxx/test/std/utilities/optional/optional.comp_with_t/equal.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.comp_with_t/equal.pass.cpp
@@ -26,7 +26,7 @@ constexpr bool operator==(const X& lhs, const X& rhs) {
   return lhs.i_ == rhs.i_;
 }
 
-int main() {
+int main(int, char**) {
   {
     typedef X T;
     typedef optional<T> O;
@@ -60,4 +60,6 @@ int main() {
     static_assert(o1 == 42, "");
     static_assert(!(101 == o1), "");
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.comp_with_t/greater.pass.cpp b/libcxx/test/std/utilities/optional/optional.comp_with_t/greater.pass.cpp
index 539e35fe0651ac3d31fcec533f7cbb799326f446..373634f68c2dc818fbe946a67118ca12f60cea3d 100644
--- a/libcxx/test/std/utilities/optional/optional.comp_with_t/greater.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.comp_with_t/greater.pass.cpp
@@ -24,7 +24,7 @@ struct X {
 
 constexpr bool operator>(const X& lhs, const X& rhs) { return lhs.i_ > rhs.i_; }
 
-int main() {
+int main(int, char**) {
   {
     typedef X T;
     typedef optional<T> O;
@@ -60,4 +60,6 @@ int main() {
     static_assert(o1 > 11, "");
     static_assert(!(42 > o1), "");
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.comp_with_t/greater_equal.pass.cpp b/libcxx/test/std/utilities/optional/optional.comp_with_t/greater_equal.pass.cpp
index c7bbbda8580f1c54e086c30fdb72fca89cf4b91f..5d4839734bb909f36f2328851766d9ee445e4e7a 100644
--- a/libcxx/test/std/utilities/optional/optional.comp_with_t/greater_equal.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.comp_with_t/greater_equal.pass.cpp
@@ -26,7 +26,7 @@ constexpr bool operator>=(const X& lhs, const X& rhs) {
   return lhs.i_ >= rhs.i_;
 }
 
-int main() {
+int main(int, char**) {
   {
     typedef X T;
     typedef optional<T> O;
@@ -62,4 +62,6 @@ int main() {
     static_assert(o1 >= 42, "");
     static_assert(!(11 >= o1), "");
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.comp_with_t/less_equal.pass.cpp b/libcxx/test/std/utilities/optional/optional.comp_with_t/less_equal.pass.cpp
index 73ed8564340d55000df5291d7f05abfcd43bb0dc..a601939c5b39def1c99b3f8a5034d48a8840e453 100644
--- a/libcxx/test/std/utilities/optional/optional.comp_with_t/less_equal.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.comp_with_t/less_equal.pass.cpp
@@ -26,7 +26,7 @@ constexpr bool operator<=(const X& lhs, const X& rhs) {
   return lhs.i_ <= rhs.i_;
 }
 
-int main() {
+int main(int, char**) {
   {
     typedef X T;
     typedef optional<T> O;
@@ -62,4 +62,6 @@ int main() {
     static_assert(o1 <= 42, "");
     static_assert(!(101 <= o1), "");
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.comp_with_t/less_than.pass.cpp b/libcxx/test/std/utilities/optional/optional.comp_with_t/less_than.pass.cpp
index c0c111afdca51751acb9f0d60127475a01182f27..7320955908a4dbd535ddf179db7cc1c048144b39 100644
--- a/libcxx/test/std/utilities/optional/optional.comp_with_t/less_than.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.comp_with_t/less_than.pass.cpp
@@ -24,7 +24,7 @@ struct X {
 
 constexpr bool operator<(const X& lhs, const X& rhs) { return lhs.i_ < rhs.i_; }
 
-int main() {
+int main(int, char**) {
   {
     typedef X T;
     typedef optional<T> O;
@@ -60,4 +60,6 @@ int main() {
     static_assert(o1 < 101, "");
     static_assert(!(42 < o1), "");
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.comp_with_t/not_equal.pass.cpp b/libcxx/test/std/utilities/optional/optional.comp_with_t/not_equal.pass.cpp
index 949a03a8c5b490c0359fdd8b0614239cd2e80388..0d14f1e97a952d25ea1089046398fbf8bbf66bcd 100644
--- a/libcxx/test/std/utilities/optional/optional.comp_with_t/not_equal.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.comp_with_t/not_equal.pass.cpp
@@ -26,7 +26,7 @@ constexpr bool operator!=(const X& lhs, const X& rhs) {
   return lhs.i_ != rhs.i_;
 }
 
-int main() {
+int main(int, char**) {
   {
     typedef X T;
     typedef optional<T> O;
@@ -60,4 +60,6 @@ int main() {
     static_assert(o1 != 101, "");
     static_assert(!(42 != o1), "");
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.hash/enabled_hash.pass.cpp b/libcxx/test/std/utilities/optional/optional.hash/enabled_hash.pass.cpp
index a842804f374ebe3fc9ff8d7ef8d70c980ea45949..66ab089dc3077cc0d0efce2a4a2287a5123b8ccf 100644
--- a/libcxx/test/std/utilities/optional/optional.hash/enabled_hash.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.hash/enabled_hash.pass.cpp
@@ -17,9 +17,11 @@
 
 #include "poisoned_hash_helper.hpp"
 
-int main() {
+int main(int, char**) {
   test_library_hash_specializations_available();
   {
 
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.hash/hash.pass.cpp b/libcxx/test/std/utilities/optional/optional.hash/hash.pass.cpp
index 0f74557b7300904545e94b2fd80cbd1254c32d54..aa89a51d8d4020c399096b909778792862964c1c 100644
--- a/libcxx/test/std/utilities/optional/optional.hash/hash.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.hash/hash.pass.cpp
@@ -30,7 +30,7 @@ struct hash<B> {
 
 }
 
-int main()
+int main(int, char**)
 {
     using std::optional;
     const std::size_t nullopt_hash =
@@ -76,4 +76,6 @@ int main()
       test_hash_enabled_for_type<std::optional<B>>();
       test_hash_enabled_for_type<std::optional<const B>>();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.nullops/equal.pass.cpp b/libcxx/test/std/utilities/optional/optional.nullops/equal.pass.cpp
index 05413c1f14dd4571f98569a09426f5f2b2def164..5894462205abcffe87877bbe3fbeda2a693b6388 100644
--- a/libcxx/test/std/utilities/optional/optional.nullops/equal.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.nullops/equal.pass.cpp
@@ -14,7 +14,7 @@
 
 #include <optional>
 
-int main()
+int main(int, char**)
 {
     using std::optional;
     using std::nullopt_t;
@@ -35,4 +35,6 @@ int main()
     static_assert (noexcept(nullopt == o1), "");
     static_assert (noexcept(o1 == nullopt), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.nullops/greater.pass.cpp b/libcxx/test/std/utilities/optional/optional.nullops/greater.pass.cpp
index 7bc764d01b8fef371aa05e00d75d88f51e252423..59dc62fce17d5239475002b1e49448bc8ed02324 100644
--- a/libcxx/test/std/utilities/optional/optional.nullops/greater.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.nullops/greater.pass.cpp
@@ -14,7 +14,7 @@
 
 #include <optional>
 
-int main()
+int main(int, char**)
 {
     using std::optional;
     using std::nullopt_t;
@@ -35,4 +35,6 @@ int main()
     static_assert (noexcept(nullopt > o1), "");
     static_assert (noexcept(o1 > nullopt), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.nullops/greater_equal.pass.cpp b/libcxx/test/std/utilities/optional/optional.nullops/greater_equal.pass.cpp
index 7c77a95a15037bb1a63b9b7220c5a3dd00f836f3..e23e8794f441db947e402ba3030bb93274de7bbc 100644
--- a/libcxx/test/std/utilities/optional/optional.nullops/greater_equal.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.nullops/greater_equal.pass.cpp
@@ -14,7 +14,7 @@
 
 #include <optional>
 
-int main()
+int main(int, char**)
 {
     using std::optional;
     using std::nullopt_t;
@@ -35,4 +35,6 @@ int main()
     static_assert (noexcept(nullopt >= o1), "");
     static_assert (noexcept(o1 >= nullopt), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.nullops/less_equal.pass.cpp b/libcxx/test/std/utilities/optional/optional.nullops/less_equal.pass.cpp
index 1d3994e4a508b3cc525a0150ded2477ff3ecbf1c..96f0754e40b3b5a4f6d0d4875ee91940d69943e0 100644
--- a/libcxx/test/std/utilities/optional/optional.nullops/less_equal.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.nullops/less_equal.pass.cpp
@@ -15,7 +15,7 @@
 
 #include <optional>
 
-int main()
+int main(int, char**)
 {
     using std::optional;
     using std::nullopt_t;
@@ -36,4 +36,6 @@ int main()
     static_assert (noexcept(nullopt <= o1), "");
     static_assert (noexcept(o1 <= nullopt), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.nullops/less_than.pass.cpp b/libcxx/test/std/utilities/optional/optional.nullops/less_than.pass.cpp
index 3b313c946d78be34652f1d34005f9117ef95bf14..872f3159a92fe0d40afbc5113fcb00626673ae5a 100644
--- a/libcxx/test/std/utilities/optional/optional.nullops/less_than.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.nullops/less_than.pass.cpp
@@ -14,7 +14,7 @@
 
 #include <optional>
 
-int main()
+int main(int, char**)
 {
     using std::optional;
     using std::nullopt_t;
@@ -35,4 +35,6 @@ int main()
     static_assert (noexcept(nullopt < o1), "");
     static_assert (noexcept(o1 < nullopt), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.nullops/not_equal.pass.cpp b/libcxx/test/std/utilities/optional/optional.nullops/not_equal.pass.cpp
index 9b3c41c1c48ebc5208064aa671d16e23054adff9..7eea0fa8856eb1521058cd86b96ef08a40e49b24 100644
--- a/libcxx/test/std/utilities/optional/optional.nullops/not_equal.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.nullops/not_equal.pass.cpp
@@ -14,7 +14,7 @@
 
 #include <optional>
 
-int main()
+int main(int, char**)
 {
     using std::optional;
     using std::nullopt_t;
@@ -35,4 +35,6 @@ int main()
     static_assert (noexcept(nullopt != o1), "");
     static_assert (noexcept(o1 != nullopt), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.nullopt/nullopt_t.fail.cpp b/libcxx/test/std/utilities/optional/optional.nullopt/nullopt_t.fail.cpp
index 9cbbc8bd9728bfc1ae3fcd8880664257f44eec6b..2a7822ebb637ddfe58f4b329c050842164d3dc89 100644
--- a/libcxx/test/std/utilities/optional/optional.nullopt/nullopt_t.fail.cpp
+++ b/libcxx/test/std/utilities/optional/optional.nullopt/nullopt_t.fail.cpp
@@ -18,7 +18,9 @@
 
 #include <optional>
 
-int main()
+int main(int, char**)
 {
     std::nullopt_t n = {};
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.nullopt/nullopt_t.pass.cpp b/libcxx/test/std/utilities/optional/optional.nullopt/nullopt_t.pass.cpp
index f664433cb42d4c4492fd8a0273a3c4fb9fad08c4..c9d843e9c2af6209232f2faab470f508eb00895f 100644
--- a/libcxx/test/std/utilities/optional/optional.nullopt/nullopt_t.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.nullopt/nullopt_t.pass.cpp
@@ -29,11 +29,13 @@ constexpr bool test()
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     static_assert(std::is_empty_v<nullopt_t>);
     static_assert(!std::is_default_constructible_v<nullopt_t>);
 
     static_assert(std::is_same_v<const nullopt_t, decltype(nullopt)>);
     static_assert(test());
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/assign_value.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/assign_value.pass.cpp
index e40af08233a6122ff67a2587037d466c80b0eca0..8d2a8a00c943cafd58ab3890cf718040ec001e5b 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/assign_value.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/assign_value.pass.cpp
@@ -241,7 +241,7 @@ enum MyEnum { Zero, One, Two, Three, FortyTwo = 42 };
 
 using Fn = void(*)();
 
-int main()
+int main(int, char**)
 {
     test_sfinae();
     // Test with instrumented type
@@ -268,4 +268,6 @@ int main()
         assert(**opt == 3);
     }
     test_throws();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/const_optional_U.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/const_optional_U.pass.cpp
index a9a1c07d898aac233978c078a57573963f929af2..6ccaafa6d6f2881f1304896cbaf682d726ad30fe 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/const_optional_U.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/const_optional_U.pass.cpp
@@ -196,7 +196,7 @@ void test_ambigious_assign() {
 }
 
 
-int main()
+int main(int, char**)
 {
     test_with_test_type();
     test_ambigious_assign();
@@ -250,4 +250,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/copy.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/copy.pass.cpp
index 8a4540e18e6cb2c8e2f0f36cc1e70bb656c37f77..5900e60461ebb047767b5b91bcbea32b2d6fb8df 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/copy.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/copy.pass.cpp
@@ -48,7 +48,7 @@ constexpr bool assign_value(optional<Tp>&& lhs) {
     return lhs.has_value() && rhs.has_value() && *lhs == *rhs;
 }
 
-int main()
+int main(int, char**)
 {
     {
         using O = optional<int>;
@@ -102,4 +102,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/emplace.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/emplace.pass.cpp
index cf09bb5ddded78bbb8c4af00d7b31fdf1797fafc..c5cebc5420bc9376397f102b2007a80b47c174d0 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/emplace.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/emplace.pass.cpp
@@ -208,7 +208,7 @@ void test_on_test_type() {
 
 
 
-int main()
+int main(int, char**)
 {
     {
         test_on_test_type<TestTypes::TestType>();
@@ -265,4 +265,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/emplace_initializer_list.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/emplace_initializer_list.pass.cpp
index 9141bea11c98c8eec1d3a305066c9966f6c8690e..446e9ae9668cd44ce46a957b2363c20f2831483e 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/emplace_initializer_list.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/emplace_initializer_list.pass.cpp
@@ -69,7 +69,7 @@ public:
 
 bool Z::dtor_called = false;
 
-int main()
+int main(int, char**)
 {
     {
         X x;
@@ -117,4 +117,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/move.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/move.pass.cpp
index 0c36da93d929820f520fe50841444e9ad75c88f5..c862c5f0efd2baf433065b42c77f0cd4a01ada38 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/move.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/move.pass.cpp
@@ -66,7 +66,7 @@ constexpr bool assign_value(optional<Tp>&& lhs) {
     return lhs.has_value() && rhs.has_value() && *lhs == Tp{101};
 }
 
-int main()
+int main(int, char**)
 {
     {
         static_assert(std::is_nothrow_move_assignable<optional<int>>::value, "");
@@ -204,4 +204,5 @@ int main()
         };
         static_assert(std::is_nothrow_move_assignable<optional<NoThrowMove>>::value, "");
     }
+    return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/nullopt_t.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/nullopt_t.pass.cpp
index e6b67430fff3a924d92518a84d64da641ef5d952..af582d73205788533d4ece16ff7e5be5342c20eb 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/nullopt_t.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/nullopt_t.pass.cpp
@@ -22,7 +22,7 @@ using std::optional;
 using std::nullopt_t;
 using std::nullopt;
 
-int main()
+int main(int, char**)
 {
     {
         optional<int> opt;
@@ -63,4 +63,6 @@ int main()
     assert(TT::alive == 0);
     assert(TT::destroyed == 1);
     TT::reset();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/optional_U.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/optional_U.pass.cpp
index d043fd1def8d8b49331049dbdbd9ed8e4e3f42bd..cabaa070b27b9a26147479e6585cb5fa68fa3b48 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/optional_U.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.assign/optional_U.pass.cpp
@@ -201,7 +201,7 @@ void test_ambigious_assign() {
 }
 
 
-int main()
+int main(int, char**)
 {
     test_with_test_type();
     test_ambigious_assign();
@@ -264,4 +264,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/U.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/U.pass.cpp
index 861ab91d80fdafe8245f8911fcaeb74812fb3bee..f91cd110f96f6d81c92efe0a973fc30f9d6ab457 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/U.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/U.pass.cpp
@@ -153,7 +153,9 @@ void test_explicit() {
 #endif
 }
 
-int main() {
+int main(int, char**) {
     test_implicit();
     test_explicit();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/const_T.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/const_T.pass.cpp
index 462811e51033a209630596ec13237b779c9631cb..1a7b36a5bf372ab568e778c5c8eb40f1bfdeac72 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/const_T.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/const_T.pass.cpp
@@ -29,7 +29,7 @@
 
 using std::optional;
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -132,4 +132,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/const_optional_U.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/const_optional_U.pass.cpp
index 4666d6d9b7f0830e0afba560616b369e2adbd863..b28d22330a9967b69ffc7061ff3d5ed0cecd0330 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/const_optional_U.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/const_optional_U.pass.cpp
@@ -78,7 +78,7 @@ public:
 };
 
 
-int main()
+int main(int, char**)
 {
     {
         typedef short U;
@@ -130,4 +130,6 @@ int main()
     }
 
     static_assert(!(std::is_constructible<optional<X>, const optional<Y>&>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/copy.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/copy.pass.cpp
index 844abda00ee310ca39aa0bec9873c5c917eeea3d..e6793cd47941486e86428341fd7f633c7e80e2f6 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/copy.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/copy.pass.cpp
@@ -113,7 +113,7 @@ void test_reference_extension()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test<int>();
     test<int>(3);
@@ -169,4 +169,6 @@ int main()
         constexpr std::optional<int> o2 = o1;
         static_assert( *o2 == 4, "" );
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/deduct.fail.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/deduct.fail.cpp
index 9439642418fb2410f2c2525a79ee02cae92b1a62..7c6ae9bcdac98487e134d0da32ff70c7548c5818 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/deduct.fail.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/deduct.fail.cpp
@@ -23,7 +23,7 @@
 
 struct A {};
 
-int main()
+int main(int, char**)
 {
 //  Test the explicit deduction guides
 
@@ -42,4 +42,6 @@ int main()
 //  optional(nullopt_t)
     std::optional opt(std::nullopt);   // expected-error-re@optional:* {{static_assert failed{{.*}} "instantiation of optional with nullopt_t is ill-formed"}}
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/deduct.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/deduct.pass.cpp
index 973b49dff1900e32f018bdd2c98475f5ac76f784..fa2edfcdd69bfb7700d264dc57c91fdcc3ad8fea 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/deduct.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/deduct.pass.cpp
@@ -23,7 +23,7 @@
 
 struct A {};
 
-int main()
+int main(int, char**)
 {
 //  Test the explicit deduction guides
     {
@@ -50,4 +50,6 @@ int main()
     assert(static_cast<bool>(opt) == static_cast<bool>(source));
     assert(*opt == *source);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/default.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/default.pass.cpp
index a00fa170609df496ad68d210c0f2ddca205dde73..3dd38da9d5713f94c73c19a46bff10e0de7db070 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/default.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/default.pass.cpp
@@ -61,7 +61,7 @@ test()
     };
 }
 
-int main()
+int main(int, char**)
 {
     test_constexpr<optional<int>>();
     test_constexpr<optional<int*>>();
@@ -77,4 +77,6 @@ int main()
     test_constexpr<optional<NonLiteralTypes::NoCtors&>>();
     test_constexpr<optional<NonLiteralTypes::NoCtors&&>>();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/explicit_const_optional_U.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/explicit_const_optional_U.pass.cpp
index 37adf8bbe06d6573d3dd081b1103005d7b3eef99..7741e0353426d49106828befc862e4ac76ac35e3 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/explicit_const_optional_U.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/explicit_const_optional_U.pass.cpp
@@ -79,7 +79,7 @@ public:
 };
 
 
-int main()
+int main(int, char**)
 {
     {
         typedef X T;
@@ -117,4 +117,6 @@ int main()
         optional<U> rhs(3);
         test<T>(rhs, true);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/explicit_optional_U.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/explicit_optional_U.pass.cpp
index ea4b7aa50dae43ebac4cb9839870ccd9a1b79363..71febba35298b2a29ed8c65ce4487f5cbbd092ca 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/explicit_optional_U.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/explicit_optional_U.pass.cpp
@@ -62,7 +62,7 @@ public:
     explicit Z(int) { TEST_THROW(6); }
 };
 
-int main()
+int main(int, char**)
 {
     {
         optional<int> rhs;
@@ -80,4 +80,6 @@ int main()
         optional<int> rhs(3);
         test<Z>(std::move(rhs), true);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/in_place_t.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/in_place_t.pass.cpp
index 5cd23bad04502a3c1154d0cb2e807bd8becd9fcc..db995b4a7e80fc8658fcd94e164005dc6545e575 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/in_place_t.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/in_place_t.pass.cpp
@@ -58,7 +58,7 @@ public:
 };
 
 
-int main()
+int main(int, char**)
 {
     {
         constexpr optional<int> opt(in_place, 5);
@@ -144,4 +144,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/initializer_list.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/initializer_list.pass.cpp
index f62e6a3a89eff2aace0ab2c20fd75740a5da597a..c8c76df2567f74ba6617849380474bf7b4afa7a2 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/initializer_list.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/initializer_list.pass.cpp
@@ -66,7 +66,7 @@ public:
         {return x.i_ == y.i_ && x.j_ == y.j_;}
 };
 
-int main()
+int main(int, char**)
 {
     {
         static_assert(!std::is_constructible<X, std::initializer_list<int>&>::value, "");
@@ -112,4 +112,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/move.fail.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/move.fail.cpp
index 622b8e428a02d83af1353c11cf7e20e215fb84f3..a8634b961c756e2af023f6f44db1694e7071b43d 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/move.fail.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/move.fail.cpp
@@ -28,9 +28,11 @@ struct S {
     };
 
 
-int main()
+int main(int, char**)
 {
     static_assert (!std::is_trivially_move_constructible_v<S>, "" );
     constexpr std::optional<S> o1;
     constexpr std::optional<S> o2 = std::move(o1);  // not constexpr
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/move.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/move.pass.cpp
index afba631bf957fad6f56ba2d5a5efc7ce64fb2ca0..bf536ec6342b2c65f5f57bed8fe657326acdeb6d 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/move.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/move.pass.cpp
@@ -151,7 +151,7 @@ void test_reference_extension()
 }
 
 
-int main()
+int main(int, char**)
 {
     test<int>();
     test<int>(3);
@@ -225,4 +225,6 @@ int main()
     constexpr std::optional<int> o2 = std::move(o1);
     static_assert( *o2 == 4, "" );
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/nullopt_t.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/nullopt_t.pass.cpp
index 850ed6ecaadd69970d9e2f6aa05cb14c6ae188d1..927ac19ead1215982ebc515ddc9051c92fecb8ba 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/nullopt_t.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/nullopt_t.pass.cpp
@@ -61,7 +61,7 @@ test()
     };
 }
 
-int main()
+int main(int, char**)
 {
     test_constexpr<optional<int>>();
     test_constexpr<optional<int*>>();
@@ -69,4 +69,6 @@ int main()
     test_constexpr<optional<NonTrivialTypes::NoCtors>>();
     test_constexpr<optional<NonConstexprTypes::NoCtors>>();
     test<optional<NonLiteralTypes::NoCtors>>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/optional_U.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/optional_U.pass.cpp
index fd74f9ae18c2691e826cc72a9a1217918572b05a..fe4252b49c7961bcd36b81b6134d7e58575a0755 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/optional_U.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/optional_U.pass.cpp
@@ -61,7 +61,7 @@ struct Z
     Z(int) { TEST_THROW(6); }
 };
 
-int main()
+int main(int, char**)
 {
     {
         optional<short> rhs;
@@ -89,4 +89,6 @@ int main()
     }
 
     static_assert(!(std::is_constructible<optional<X>, optional<Z>>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/rvalue_T.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/rvalue_T.pass.cpp
index 5e9a216dcb961050b2f9586247815e4781b54997..7fd1f2fa16e090cfe2f967e83f3ce156b488fcbd 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/rvalue_T.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/rvalue_T.pass.cpp
@@ -39,7 +39,7 @@ public:
 };
 
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -157,4 +157,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.dtor/dtor.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.dtor/dtor.pass.cpp
index ca96586a1391d4f0f95009be2d438e597669778b..23497bc4c47867baaa9f2bcb7bc22ad41d989ec0 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.dtor/dtor.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.dtor/dtor.pass.cpp
@@ -32,7 +32,7 @@ public:
 
 bool X::dtor_called = false;
 
-int main()
+int main(int, char**)
 {
     {
         typedef int T;
@@ -64,4 +64,6 @@ int main()
         }
         assert(X::dtor_called == true);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.mod/reset.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.mod/reset.pass.cpp
index e766db87eb6c3b6750c7f6fff5ec2a09dac71b40..704606c6f75c74885377f6c34c007ff82df0d3ab 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.mod/reset.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.mod/reset.pass.cpp
@@ -26,7 +26,7 @@ struct X
 
 bool X::dtor_called = false;
 
-int main()
+int main(int, char**)
 {
     {
         optional<int> opt;
@@ -55,4 +55,6 @@ int main()
         assert(static_cast<bool>(opt) == false);
         X::dtor_called = false;
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/bool.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/bool.pass.cpp
index 29bf20bbd0841c01fa141eb17337753fc16b7c56..7c008ef62093b081a84ebd7dbbc2ea7e4a4eb7a9 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/bool.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/bool.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using std::optional;
     {
@@ -33,4 +33,6 @@ int main()
         constexpr optional<int> opt(0);
         static_assert(opt, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/dereference.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/dereference.pass.cpp
index b109346f588c6ed736633ddafb894badf103b8d9..368f84155dbde3612ad74bd65b3ae1318e7446b9 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/dereference.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/dereference.pass.cpp
@@ -43,7 +43,7 @@ test()
     return (*opt).test();
 }
 
-int main()
+int main(int, char**)
 {
     {
         optional<X> opt; ((void)opt);
@@ -69,4 +69,6 @@ int main()
         assert(false);
     }
 #endif  // _LIBCPP_DEBUG
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/dereference_const.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/dereference_const.pass.cpp
index 6663d88513f66e838563ff365c280e3edbf01605..99a60e8dd6f75f914d57e103d980512e9ba634e5 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/dereference_const.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/dereference_const.pass.cpp
@@ -36,7 +36,7 @@ struct Y
     int test() const {return 2;}
 };
 
-int main()
+int main(int, char**)
 {
     {
         const optional<X> opt; ((void)opt);
@@ -65,4 +65,6 @@ int main()
         assert(false);
     }
 #endif  // _LIBCPP_DEBUG
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/dereference_const_rvalue.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/dereference_const_rvalue.pass.cpp
index 02466d53b11b1aa0bac532255979f832263cb038..ca494c5a83d3943c6a5e179ecf9fda6d54325274 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/dereference_const_rvalue.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/dereference_const_rvalue.pass.cpp
@@ -36,7 +36,7 @@ struct Y
     int test() const && {return 2;}
 };
 
-int main()
+int main(int, char**)
 {
     {
         const optional<X> opt; ((void)opt);
@@ -65,4 +65,6 @@ int main()
         assert(false);
     }
 #endif  // _LIBCPP_DEBUG
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/dereference_rvalue.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/dereference_rvalue.pass.cpp
index 7dca9f6134515bfecc887bdcb9fa78fa000aeaa0..f1b2ca393af3b44d96da9033753009c5b7c7e708 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/dereference_rvalue.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/dereference_rvalue.pass.cpp
@@ -43,7 +43,7 @@ test()
     return (*std::move(opt)).test();
 }
 
-int main()
+int main(int, char**)
 {
     {
         optional<X> opt; ((void)opt);
@@ -69,4 +69,6 @@ int main()
         assert(false);
     }
 #endif  // _LIBCPP_DEBUG
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/has_value.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/has_value.pass.cpp
index 59ce4c7e8eec74fcf827eea6b9a0c8c02de9305d..560fa8894b7b83b1a93b6607738fc4e59da46103 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/has_value.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/has_value.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using std::optional;
     {
@@ -33,4 +33,6 @@ int main()
         constexpr optional<int> opt(0);
         static_assert(opt.has_value(), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/op_arrow.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/op_arrow.pass.cpp
index ac0b9a52788043af27d1309cb8aaa87c8f3ae353..8c6c0986140486189c3c0e3a505712e36c7f1d8f 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/op_arrow.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/op_arrow.pass.cpp
@@ -40,7 +40,7 @@ test()
     return opt->test();
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::optional<X> opt; ((void)opt);
@@ -68,4 +68,6 @@ int main()
         assert(false);
     }
 #endif  // _LIBCPP_DEBUG
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/op_arrow_const.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/op_arrow_const.pass.cpp
index fd7e683be77cf4f3a6a1800a2fc94ed902f89f5d..b9539828a983c7a371b210901ab3fdc80eb93030 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/op_arrow_const.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/op_arrow_const.pass.cpp
@@ -39,7 +39,7 @@ struct Z
     constexpr int test() const {return 1;}
 };
 
-int main()
+int main(int, char**)
 {
     {
         const std::optional<X> opt; ((void)opt);
@@ -72,4 +72,6 @@ int main()
         assert(false);
     }
 #endif  // _LIBCPP_DEBUG
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/value.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/value.pass.cpp
index 04a4fcffd9092a817c0ad13c79e2d84cbc4ae473..23fd85ba53fce898479c188a9793c68f483448b3 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/value.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/value.pass.cpp
@@ -52,7 +52,7 @@ test()
 }
 
 
-int main()
+int main(int, char**)
 {
     {
         optional<X> opt; ((void)opt);
@@ -78,4 +78,6 @@ int main()
     }
 #endif
     static_assert(test() == 7, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/value_const.fail.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/value_const.fail.cpp
index ab6504dba9f93cbbb63daa5a626c3fc907defbb8..5e81f2fb11d2a8a44d0a8546e55b1d93fc3c4d81 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/value_const.fail.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/value_const.fail.cpp
@@ -23,10 +23,12 @@ struct X
     int test() {return 4;}
 };
 
-int main()
+int main(int, char**)
 {
     {
         constexpr optional<X> opt;
         static_assert(opt.value().test() == 3, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/value_const.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/value_const.pass.cpp
index dcc9306b152ccedd01d249008f475cb11b2e1577..54bdc1001d9a79293728858a1957479cc3831e89 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/value_const.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/value_const.pass.cpp
@@ -41,7 +41,7 @@ struct X
     int test() && {return 6;}
 };
 
-int main()
+int main(int, char**)
 {
     {
         const optional<X> opt; ((void)opt);
@@ -69,4 +69,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/value_const_rvalue.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/value_const_rvalue.pass.cpp
index 5e218d80e3f64f89140c2ca71077bef3233a58cf..b330bb8db8780f7865b6286c028ca636b2b0bdc9 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/value_const_rvalue.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/value_const_rvalue.pass.cpp
@@ -41,7 +41,7 @@ struct X
     int test() && {return 6;}
 };
 
-int main()
+int main(int, char**)
 {
     {
         const optional<X> opt; ((void)opt);
@@ -69,4 +69,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/value_or.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/value_or.pass.cpp
index 93ec45b0bec14c13a16741f4c886ebe7e0b641c9..8f22f1c0dc8e5ded8f862c5628cf635147adf912 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/value_or.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/value_or.pass.cpp
@@ -67,7 +67,9 @@ constexpr int test()
     return 0;
 }
 
-int main()
+int main(int, char**)
 {
     static_assert(test() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/value_or_const.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/value_or_const.pass.cpp
index 0b4c7928f212f8c922091abd8c236863053fdbbd..736fe791af62e739140a493eacc99245b5fd1d6a 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/value_or_const.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/value_or_const.pass.cpp
@@ -35,7 +35,7 @@ struct X
         {return x.i_ == y.i_;}
 };
 
-int main()
+int main(int, char**)
 {
     {
         constexpr optional<X> opt(2);
@@ -73,4 +73,6 @@ int main()
         const optional<X> opt;
         assert(opt.value_or(Y(3)) == 4);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/value_rvalue.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/value_rvalue.pass.cpp
index 21f630e8c364d1e78e12f0b026a76738d1aab02f..06206a324d47c121591366eb33a4ad0a77774193 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/value_rvalue.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.observe/value_rvalue.pass.cpp
@@ -50,7 +50,7 @@ test()
     return std::move(opt).value().test();
 }
 
-int main()
+int main(int, char**)
 {
     {
         optional<X> opt; ((void)opt);
@@ -76,4 +76,6 @@ int main()
     }
 #endif
     static_assert(test() == 7, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional.object.swap/swap.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/optional.object.swap/swap.pass.cpp
index 7d79251e2413e71ea48c62f815b4431b769f913a..e881a0c6286a07db11c16cc4a142dada84e0eca4 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional.object.swap/swap.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional.object.swap/swap.pass.cpp
@@ -64,7 +64,7 @@ public:
 };
 
 
-int main()
+int main(int, char**)
 {
     {
         optional<int> opt1;
@@ -302,4 +302,6 @@ int main()
         assert(*opt2 == 2);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/optional_requires_destructible_object.fail.cpp b/libcxx/test/std/utilities/optional/optional.object/optional_requires_destructible_object.fail.cpp
index 67e1b76d7cbcf500aaabed046c4aaa03fcb32558..531173ade8b7866793b34cb33b1467dd2b7ca8e0 100644
--- a/libcxx/test/std/utilities/optional/optional.object/optional_requires_destructible_object.fail.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/optional_requires_destructible_object.fail.cpp
@@ -21,7 +21,7 @@ private:
     ~X() {}
 };
 
-int main()
+int main(int, char**)
 {
     using std::optional;
     {
@@ -46,4 +46,6 @@ int main()
     }
     // FIXME these are garbage diagnostics that Clang should not produce
     // expected-error@optional:* 0+ {{is not a base class}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/special_members.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/special_members.pass.cpp
index a315ed8ca75942d6e9a4ec5e2b9b94e65db37f32..28783264d715f988df30a615654b88978bbaa0b6 100644
--- a/libcxx/test/std/utilities/optional/optional.object/special_members.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/special_members.pass.cpp
@@ -52,11 +52,12 @@ struct DoTestsMetafunction {
     DoTestsMetafunction() { sink(SpecialMemberTest<TestTypes>{}...); }
 };
 
-int main() {
+int main(int, char**) {
     sink(
         ImplicitTypes::ApplyTypes<DoTestsMetafunction>{},
         ExplicitTypes::ApplyTypes<DoTestsMetafunction>{},
         NonLiteralTypes::ApplyTypes<DoTestsMetafunction>{},
         NonTrivialTypes::ApplyTypes<DoTestsMetafunction>{}
     );
+    return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/triviality.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/triviality.pass.cpp
index 7c82e17d6118b8c9f06463b3974b9668fbc90798..f53d86000e7c712f0725f2d45b74e32cc3b34187 100644
--- a/libcxx/test/std/utilities/optional/optional.object/triviality.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/triviality.pass.cpp
@@ -85,7 +85,7 @@ struct TrivialCopyNonTrivialMove {
     TrivialCopyNonTrivialMove& operator=(TrivialCopyNonTrivialMove&&) { return *this; }
 };
 
-int main() {
+int main(int, char**) {
     sink(
         ImplicitTypes::ApplyTypes<DoTestsMetafunction>{},
         ExplicitTypes::ApplyTypes<DoTestsMetafunction>{},
@@ -93,4 +93,5 @@ int main() {
         NonTrivialTypes::ApplyTypes<DoTestsMetafunction>{},
         DoTestsMetafunction<TrivialMoveNonTrivialCopy, TrivialCopyNonTrivialMove>{}
     );
+    return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.object/types.pass.cpp b/libcxx/test/std/utilities/optional/optional.object/types.pass.cpp
index cef295754ee83ab3e7a2818a89d612e84c94f738..7c32d1857cd0054d64d42a95706d39ee20984f2e 100644
--- a/libcxx/test/std/utilities/optional/optional.object/types.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.object/types.pass.cpp
@@ -28,10 +28,12 @@ test()
     static_assert(std::is_same<typename Opt::value_type, T>::value, "");
 }
 
-int main()
+int main(int, char**)
 {
     test<optional<int>, int>();
     test<optional<const int>, const int>();
     test<optional<double>, double>();
     test<optional<const double>, const double>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.relops/equal.pass.cpp b/libcxx/test/std/utilities/optional/optional.relops/equal.pass.cpp
index baeb16bb6b854f85a521700efc464196a3fee402..4fc85157a7685d13b983802b5461c84e4dacba78 100644
--- a/libcxx/test/std/utilities/optional/optional.relops/equal.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.relops/equal.pass.cpp
@@ -27,7 +27,7 @@ constexpr bool operator==(const X& lhs, const X& rhs) {
   return lhs.i_ == rhs.i_;
 }
 
-int main() {
+int main(int, char**) {
   {
     typedef X T;
     typedef optional<T> O;
@@ -82,4 +82,6 @@ int main() {
     static_assert(o1 == O2(42), "");
     static_assert(!(O2(101) == o1), "");
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.relops/greater_equal.pass.cpp b/libcxx/test/std/utilities/optional/optional.relops/greater_equal.pass.cpp
index 3a88640cad903720313486f4e4eb42f38e9e75cb..4bc9720aa7f7a5fd12113b57a32822440ee3a55f 100644
--- a/libcxx/test/std/utilities/optional/optional.relops/greater_equal.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.relops/greater_equal.pass.cpp
@@ -25,7 +25,7 @@ constexpr bool operator>=(const X& lhs, const X& rhs) {
   return lhs.i_ >= rhs.i_;
 }
 
-int main() {
+int main(int, char**) {
   {
     typedef optional<X> O;
 
@@ -79,4 +79,6 @@ int main() {
     static_assert(o1 >= O2(42), "");
     static_assert(!(O2(1) >= o1), "");
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.relops/greater_than.pass.cpp b/libcxx/test/std/utilities/optional/optional.relops/greater_than.pass.cpp
index 7f7b24a75f68baea9608f834108755b251946b51..d168cd70635a5f53d4b66803a745aaccf95bf47a 100644
--- a/libcxx/test/std/utilities/optional/optional.relops/greater_than.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.relops/greater_than.pass.cpp
@@ -23,7 +23,7 @@ struct X {
 
 constexpr bool operator>(const X& lhs, const X& rhs) { return lhs.i_ > rhs.i_; }
 
-int main() {
+int main(int, char**) {
   {
     typedef optional<X> O;
 
@@ -77,4 +77,6 @@ int main() {
     static_assert(o1 > O2(1), "");
     static_assert(!(O2(42) > o1), "");
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.relops/less_equal.pass.cpp b/libcxx/test/std/utilities/optional/optional.relops/less_equal.pass.cpp
index e9180cb3ee6c01007565144aabbbe50c550254b2..835be64f8fbee101698eaf0f07622c7aa52bdeb7 100644
--- a/libcxx/test/std/utilities/optional/optional.relops/less_equal.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.relops/less_equal.pass.cpp
@@ -25,7 +25,7 @@ constexpr bool operator<=(const X& lhs, const X& rhs) {
   return lhs.i_ <= rhs.i_;
 }
 
-int main() {
+int main(int, char**) {
   {
     typedef optional<X> O;
 
@@ -79,4 +79,6 @@ int main() {
     static_assert(o1 <= O2(42), "");
     static_assert(!(O2(101) <= o1), "");
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.relops/less_than.pass.cpp b/libcxx/test/std/utilities/optional/optional.relops/less_than.pass.cpp
index 29fa36a3edbe96b15b619cff6427205b0bf98c4a..832de4b2981a63364fdea1a96bc2ad2a030225c0 100644
--- a/libcxx/test/std/utilities/optional/optional.relops/less_than.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.relops/less_than.pass.cpp
@@ -23,7 +23,7 @@ struct X {
 
 constexpr bool operator<(const X& lhs, const X& rhs) { return lhs.i_ < rhs.i_; }
 
-int main() {
+int main(int, char**) {
   {
     typedef optional<X> O;
 
@@ -77,4 +77,6 @@ int main() {
     static_assert(o1 < O2(101), "");
     static_assert(!(O2(101) < o1), "");
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.relops/not_equal.pass.cpp b/libcxx/test/std/utilities/optional/optional.relops/not_equal.pass.cpp
index 9f690477e0eab8243cb160f5fdb0ee3472f65ff8..ab00b7aab18dc8fc9e612426a1370000ce44c95d 100644
--- a/libcxx/test/std/utilities/optional/optional.relops/not_equal.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.relops/not_equal.pass.cpp
@@ -27,7 +27,7 @@ constexpr bool operator!=(const X& lhs, const X& rhs) {
   return lhs.i_ != rhs.i_;
 }
 
-int main() {
+int main(int, char**) {
   {
     typedef X T;
     typedef optional<T> O;
@@ -82,4 +82,6 @@ int main() {
     static_assert(o1 != O2(101), "");
     static_assert(!(O2(42) != o1), "");
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.specalg/make_optional.pass.cpp b/libcxx/test/std/utilities/optional/optional.specalg/make_optional.pass.cpp
index fef17e772774aca20160d5efbfbb4dd4cf8022a8..7725289275f90d82417d45b83284a49c80b986a8 100644
--- a/libcxx/test/std/utilities/optional/optional.specalg/make_optional.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.specalg/make_optional.pass.cpp
@@ -27,7 +27,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using std::optional;
     using std::make_optional;
@@ -55,4 +55,6 @@ int main()
         assert(**opt == 3);
         assert(s == nullptr);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.specalg/make_optional_explicit.pass.cpp b/libcxx/test/std/utilities/optional/optional.specalg/make_optional_explicit.pass.cpp
index 675e9003673671f04b6d448846b378d882e175f8..d3461542b93e83b2afb1bb50dbae6a4ccb08176f 100644
--- a/libcxx/test/std/utilities/optional/optional.specalg/make_optional_explicit.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.specalg/make_optional_explicit.pass.cpp
@@ -17,7 +17,7 @@
 #include <memory>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     using std::optional;
     using std::make_optional;
@@ -41,4 +41,6 @@ int main()
         auto opt = make_optional<std::string>(4, 'X');
         assert(*opt == "XXXX");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.specalg/make_optional_explicit_initializer_list.pass.cpp b/libcxx/test/std/utilities/optional/optional.specalg/make_optional_explicit_initializer_list.pass.cpp
index 4a9040e50f7cfd78d736e773f944e33838122a04..40b20bed52b9e4d3e9c6cca4f7fd80a83462630c 100644
--- a/libcxx/test/std/utilities/optional/optional.specalg/make_optional_explicit_initializer_list.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.specalg/make_optional_explicit_initializer_list.pass.cpp
@@ -27,7 +27,7 @@ struct TestT {
       : x(*il.begin()), size(static_cast<int>(il.size())) {}
 };
 
-int main()
+int main(int, char**)
 {
     using std::make_optional;
     {
@@ -49,4 +49,6 @@ int main()
         auto opt = make_optional<std::string>({'a', 'b', 'c'}, std::allocator<char>{});
         assert(*opt == "abc");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.specalg/swap.pass.cpp b/libcxx/test/std/utilities/optional/optional.specalg/swap.pass.cpp
index 3f37ac6e272b4ea5dd9f9a7362a937b2d1789df8..1a548e8cc2e7ddd5a745133f9cce48f8a5467c6f 100644
--- a/libcxx/test/std/utilities/optional/optional.specalg/swap.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.specalg/swap.pass.cpp
@@ -109,7 +109,7 @@ void test_swap_sfinae() {
     }
 }
 
-int main()
+int main(int, char**)
 {
     test_swap_sfinae();
     {
@@ -348,4 +348,6 @@ int main()
         assert(*opt2 == 2);
     }
 #endif // TEST_HAS_NO_EXCEPTIONS
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.syn/optional_in_place_t.fail.cpp b/libcxx/test/std/utilities/optional/optional.syn/optional_in_place_t.fail.cpp
index aca546d6c44730f8490fdb587f82856078e84d00..b7d3b71e0d3a67f11cf92df32e9581266da29266 100644
--- a/libcxx/test/std/utilities/optional/optional.syn/optional_in_place_t.fail.cpp
+++ b/libcxx/test/std/utilities/optional/optional.syn/optional_in_place_t.fail.cpp
@@ -14,7 +14,7 @@
 
 #include <optional>
 
-int main()
+int main(int, char**)
 {
     using std::optional;
     using std::in_place_t;
@@ -22,4 +22,6 @@ int main()
 
     optional<in_place_t> opt; // expected-note {{requested here}}
     // expected-error@optional:* {{"instantiation of optional with in_place_t is ill-formed"}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.syn/optional_includes_initializer_list.pass.cpp b/libcxx/test/std/utilities/optional/optional.syn/optional_includes_initializer_list.pass.cpp
index 28904aecf121d3553706983af0dcb7da36136841..daaad5664b6b80d35a035411e319fa0cad200b47 100644
--- a/libcxx/test/std/utilities/optional/optional.syn/optional_includes_initializer_list.pass.cpp
+++ b/libcxx/test/std/utilities/optional/optional.syn/optional_includes_initializer_list.pass.cpp
@@ -13,10 +13,12 @@
 
 #include <optional>
 
-int main()
+int main(int, char**)
 {
     using std::optional;
 
     std::initializer_list<int> list;
     (void)list;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/optional/optional.syn/optional_nullopt_t.fail.cpp b/libcxx/test/std/utilities/optional/optional.syn/optional_nullopt_t.fail.cpp
index 4fe41b44518fc219ede9905c51ed8d0828405634..a4abbf02779d66377de1ead2bb36eb102515b65f 100644
--- a/libcxx/test/std/utilities/optional/optional.syn/optional_nullopt_t.fail.cpp
+++ b/libcxx/test/std/utilities/optional/optional.syn/optional_nullopt_t.fail.cpp
@@ -14,7 +14,7 @@
 
 #include <optional>
 
-int main()
+int main(int, char**)
 {
     using std::optional;
     using std::nullopt_t;
@@ -25,4 +25,6 @@ int main()
     optional<nullopt_t &> opt2; // expected-note 1 {{requested here}}
     optional<nullopt_t &&> opt3; // expected-note 1 {{requested here}}
     // expected-error@optional:* 4 {{instantiation of optional with nullopt_t is ill-formed}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_add.fail.cpp b/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_add.fail.cpp
index d7f775eee6e35140b0a3298c5eadca4c46aa17b9..abf75631f861d32fa6dc6e8f1105d7b1cfedc7b1 100644
--- a/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_add.fail.cpp
+++ b/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_add.fail.cpp
@@ -10,9 +10,11 @@
 
 #include <ratio>
 
-int main()
+int main(int, char**)
 {
     typedef std::ratio<0x7FFFFFFFFFFFFFFFLL, 1> R1;
     typedef std::ratio<1, 1> R2;
     typedef std::ratio_add<R1, R2>::type R;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_add.pass.cpp b/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_add.pass.cpp
index ae43ac9222b08d5e55a0906f5c5d08a598691876..c62f75a0d875f569d8eb2b205df195e9a32160bc 100644
--- a/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_add.pass.cpp
+++ b/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_add.pass.cpp
@@ -10,7 +10,7 @@
 
 #include <ratio>
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::ratio<1, 1> R1;
@@ -72,4 +72,6 @@ int main()
     typedef std::ratio_add<R1, R2>::type R;
     static_assert(R::num == 1 && R::den == 1, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_divide.fail.cpp b/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_divide.fail.cpp
index ea96434b8552b376984aad330a6f97d3f5ca380c..387f6290368ec6c3e9ecc0937f6de4ef754cf4e2 100644
--- a/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_divide.fail.cpp
+++ b/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_divide.fail.cpp
@@ -10,9 +10,11 @@
 
 #include <ratio>
 
-int main()
+int main(int, char**)
 {
     typedef std::ratio<0x7FFFFFFFFFFFFFFFLL, 1> R1;
     typedef std::ratio<1, 2> R2;
     typedef std::ratio_divide<R1, R2>::type R;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_divide.pass.cpp b/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_divide.pass.cpp
index 0b93e1a9cea06308635d9d893107c34a9621a1a3..ce7f69473bc797bca69d4afcd540b93de0a6d0f4 100644
--- a/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_divide.pass.cpp
+++ b/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_divide.pass.cpp
@@ -10,7 +10,7 @@
 
 #include <ratio>
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::ratio<1, 1> R1;
@@ -54,4 +54,6 @@ int main()
     typedef std::ratio_divide<R1, R2>::type R;
     static_assert(R::num == 630992477165LL && R::den == 127339199162436LL, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_multiply.fail.cpp b/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_multiply.fail.cpp
index b884f4e2cb8d6372857d4132452a4b9bb57604e5..ef59bb39e41f30f6a20794a98a21224b6f7a3bd4 100644
--- a/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_multiply.fail.cpp
+++ b/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_multiply.fail.cpp
@@ -10,9 +10,11 @@
 
 #include <ratio>
 
-int main()
+int main(int, char**)
 {
     typedef std::ratio<0x7FFFFFFFFFFFFFFFLL, 1> R1;
     typedef std::ratio<2, 1> R2;
     typedef std::ratio_multiply<R1, R2>::type R;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_multiply.pass.cpp b/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_multiply.pass.cpp
index 876158994e7ca68b1f110443bec963f6f1b9d6f2..e20f234434743f58997e12a57f9cd7c5bb82c7cd 100644
--- a/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_multiply.pass.cpp
+++ b/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_multiply.pass.cpp
@@ -10,7 +10,7 @@
 
 #include <ratio>
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::ratio<1, 1> R1;
@@ -54,4 +54,6 @@ int main()
     typedef std::ratio_multiply<R1, R2>::type R;
     static_assert(R::num == 15519594064236LL && R::den == 5177331081415LL, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_subtract.fail.cpp b/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_subtract.fail.cpp
index 95e9c823908f2b5558584a2cbaf769b6f15ec601..8b00462dc48ed62e665b5f1d93635d9f0b94a860 100644
--- a/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_subtract.fail.cpp
+++ b/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_subtract.fail.cpp
@@ -10,9 +10,11 @@
 
 #include <ratio>
 
-int main()
+int main(int, char**)
 {
     typedef std::ratio<-0x7FFFFFFFFFFFFFFFLL, 1> R1;
     typedef std::ratio<1, 1> R2;
     typedef std::ratio_subtract<R1, R2>::type R;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_subtract.pass.cpp b/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_subtract.pass.cpp
index dbb9480475d30d879738b73a6cc0aa7b976d1149..e3871f7a7cfc94eb116f0201e2355b82412b5c50 100644
--- a/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_subtract.pass.cpp
+++ b/libcxx/test/std/utilities/ratio/ratio.arithmetic/ratio_subtract.pass.cpp
@@ -10,7 +10,7 @@
 
 #include <ratio>
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::ratio<1, 1> R1;
@@ -72,4 +72,6 @@ int main()
     typedef std::ratio_subtract<R1, R2>::type R;
     static_assert(R::num == -1 && R::den == 1, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/ratio/ratio.comparison/ratio_equal.pass.cpp b/libcxx/test/std/utilities/ratio/ratio.comparison/ratio_equal.pass.cpp
index 9f547cdea565e82531253c477685e03850f67111..d0b1d5a17be113fe9c32abdb9989fa076990461a 100644
--- a/libcxx/test/std/utilities/ratio/ratio.comparison/ratio_equal.pass.cpp
+++ b/libcxx/test/std/utilities/ratio/ratio.comparison/ratio_equal.pass.cpp
@@ -21,7 +21,7 @@ void test()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::ratio<1, 1> R1;
@@ -63,4 +63,6 @@ int main()
     typedef std::ratio<1, -0x7FFFFFFFFFFFFFFFLL> R2;
     test<R1, R2, false>();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/ratio/ratio.comparison/ratio_greater.pass.cpp b/libcxx/test/std/utilities/ratio/ratio.comparison/ratio_greater.pass.cpp
index ab6deac86d05ef17e436b6c57e306826bb4b1924..dfb0e8fe87e28fafacafc8ca3f3625c1dec7bf5f 100644
--- a/libcxx/test/std/utilities/ratio/ratio.comparison/ratio_greater.pass.cpp
+++ b/libcxx/test/std/utilities/ratio/ratio.comparison/ratio_greater.pass.cpp
@@ -21,7 +21,7 @@ void test()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::ratio<1, 1> R1;
@@ -63,4 +63,6 @@ int main()
     typedef std::ratio<1, -0x7FFFFFFFFFFFFFFFLL> R2;
     test<R1, R2, true>();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/ratio/ratio.comparison/ratio_greater_equal.pass.cpp b/libcxx/test/std/utilities/ratio/ratio.comparison/ratio_greater_equal.pass.cpp
index 79942fa6d0d35c22990166b75e124670d4955e16..811706c58aaa9f5ddc7df08f4a310424c38b52b6 100644
--- a/libcxx/test/std/utilities/ratio/ratio.comparison/ratio_greater_equal.pass.cpp
+++ b/libcxx/test/std/utilities/ratio/ratio.comparison/ratio_greater_equal.pass.cpp
@@ -21,7 +21,7 @@ void test()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::ratio<1, 1> R1;
@@ -63,4 +63,6 @@ int main()
     typedef std::ratio<1, -0x7FFFFFFFFFFFFFFFLL> R2;
     test<R1, R2, true>();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/ratio/ratio.comparison/ratio_less.pass.cpp b/libcxx/test/std/utilities/ratio/ratio.comparison/ratio_less.pass.cpp
index a80112ca4b8ededcfac28361fdea05d4d65e3d80..45ba7cbf16cbdf318a89762e27087d0d99adce54 100644
--- a/libcxx/test/std/utilities/ratio/ratio.comparison/ratio_less.pass.cpp
+++ b/libcxx/test/std/utilities/ratio/ratio.comparison/ratio_less.pass.cpp
@@ -21,7 +21,7 @@ void test()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::ratio<1, 1> R1;
@@ -93,4 +93,6 @@ int main()
     typedef std::ratio<641981, 1339063> R2;
     test<R1, R2, true>();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/ratio/ratio.comparison/ratio_less_equal.pass.cpp b/libcxx/test/std/utilities/ratio/ratio.comparison/ratio_less_equal.pass.cpp
index c5dbdedc8f6a1fedc54b9e85085bdc8b70ee201c..ebb8624a85f25f8215a1d9b4c1c8953f7b055b47 100644
--- a/libcxx/test/std/utilities/ratio/ratio.comparison/ratio_less_equal.pass.cpp
+++ b/libcxx/test/std/utilities/ratio/ratio.comparison/ratio_less_equal.pass.cpp
@@ -21,7 +21,7 @@ void test()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::ratio<1, 1> R1;
@@ -63,4 +63,6 @@ int main()
     typedef std::ratio<1, -0x7FFFFFFFFFFFFFFFLL> R2;
     test<R1, R2, false>();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/ratio/ratio.comparison/ratio_not_equal.pass.cpp b/libcxx/test/std/utilities/ratio/ratio.comparison/ratio_not_equal.pass.cpp
index 68e6aba35d0f4e19170806f50c22d70fad5aa8ab..5000e73d3fcf8e39b820866aaf4a7ec6335e3f25 100644
--- a/libcxx/test/std/utilities/ratio/ratio.comparison/ratio_not_equal.pass.cpp
+++ b/libcxx/test/std/utilities/ratio/ratio.comparison/ratio_not_equal.pass.cpp
@@ -21,7 +21,7 @@ void test()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::ratio<1, 1> R1;
@@ -63,4 +63,6 @@ int main()
     typedef std::ratio<1, -0x7FFFFFFFFFFFFFFFLL> R2;
     test<R1, R2, true>();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/ratio/ratio.ratio/ratio.pass.cpp b/libcxx/test/std/utilities/ratio/ratio.ratio/ratio.pass.cpp
index bb3bb159bde2d1d5e18fed9d4df53ef1bbda5c80..336d7d8e5b58da43fd73bdb13940701083443731 100644
--- a/libcxx/test/std/utilities/ratio/ratio.ratio/ratio.pass.cpp
+++ b/libcxx/test/std/utilities/ratio/ratio.ratio/ratio.pass.cpp
@@ -18,7 +18,7 @@ void test()
     static_assert((std::ratio<N, D>::den == eD), "");
 }
 
-int main()
+int main(int, char**)
 {
     test<1, 1, 1, 1>();
     test<1, 10, 1, 10>();
@@ -40,4 +40,6 @@ int main()
     test<-0x7FFFFFFFFFFFFFFFLL, 127, -72624976668147841LL, 1>();
     test<0x7FFFFFFFFFFFFFFFLL, -127, -72624976668147841LL, 1>();
     test<-0x7FFFFFFFFFFFFFFFLL, -127, 72624976668147841LL, 1>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/ratio/ratio.ratio/ratio1.fail.cpp b/libcxx/test/std/utilities/ratio/ratio.ratio/ratio1.fail.cpp
index 1c143f659cb81f4bb3b0a45aeb54f198facdc51a..0841d858dc96c2531d7a4b58614714f5b06eb945 100644
--- a/libcxx/test/std/utilities/ratio/ratio.ratio/ratio1.fail.cpp
+++ b/libcxx/test/std/utilities/ratio/ratio.ratio/ratio1.fail.cpp
@@ -11,7 +11,9 @@
 #include <ratio>
 #include <cstdint>
 
-int main()
+int main(int, char**)
 {
     const std::intmax_t t1 = std::ratio<1, 0>::num;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/ratio/ratio.ratio/ratio2.fail.cpp b/libcxx/test/std/utilities/ratio/ratio.ratio/ratio2.fail.cpp
index bf56271fbbebe6ffea75004668e58eae4947b9b4..f8bebc8624dfadd6a0959ad51733c1d944ba86ed 100644
--- a/libcxx/test/std/utilities/ratio/ratio.ratio/ratio2.fail.cpp
+++ b/libcxx/test/std/utilities/ratio/ratio.ratio/ratio2.fail.cpp
@@ -12,7 +12,9 @@
 #include <ratio>
 #include <cstdint>
 
-int main()
+int main(int, char**)
 {
     const std::intmax_t t1 = std::ratio<0x8000000000000000ULL, 1>::num;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/ratio/ratio.ratio/ratio3.fail.cpp b/libcxx/test/std/utilities/ratio/ratio.ratio/ratio3.fail.cpp
index 6e44427f841bf7e45e56199207b2621d4834a4b8..78310c6a2454e80d67eaf997e47cdfbee86eefde 100644
--- a/libcxx/test/std/utilities/ratio/ratio.ratio/ratio3.fail.cpp
+++ b/libcxx/test/std/utilities/ratio/ratio.ratio/ratio3.fail.cpp
@@ -12,7 +12,9 @@
 #include <ratio>
 #include <cstdint>
 
-int main()
+int main(int, char**)
 {
     const std::intmax_t t1 = std::ratio<1, 0x8000000000000000ULL>::num;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/ratio/ratio.si/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/ratio/ratio.si/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/ratio/ratio.si/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/ratio/ratio.si/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/ratio/typedefs.pass.cpp b/libcxx/test/std/utilities/ratio/typedefs.pass.cpp
index 3f54f555a89f6bdb6c577a857e9c29509531b131..8e24ff9749d356f410d681c8d320c3b40bbc9d05 100644
--- a/libcxx/test/std/utilities/ratio/typedefs.pass.cpp
+++ b/libcxx/test/std/utilities/ratio/typedefs.pass.cpp
@@ -10,7 +10,7 @@
 
 #include <ratio>
 
-int main()
+int main(int, char**)
 {
     static_assert(std::atto::num == 1 && std::atto::den == 1000000000000000000ULL, "");
     static_assert(std::femto::num == 1 && std::femto::den == 1000000000000000ULL, "");
@@ -28,4 +28,6 @@ int main()
     static_assert(std::tera::num == 1000000000000ULL && std::tera::den == 1, "");
     static_assert(std::peta::num == 1000000000000000ULL && std::peta::den == 1, "");
     static_assert(std::exa::num == 1000000000000000000ULL && std::exa::den == 1, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/pointer_type.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/pointer_type.pass.cpp
index cb7a5bbf6abbb7768865ab96ccb4fe99b3dce191..f0ca5b0ea86f04b84fef885a1098b681f650bd39 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/pointer_type.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/pointer_type.pass.cpp
@@ -54,7 +54,9 @@ void test_basic() {
 #endif
 }
 
-int main() {
+int main(int, char**) {
   test_basic</*IsArray*/ false>();
   test_basic<true>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.asgn/move.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.asgn/move.pass.cpp
index e11ec4b40042b1033f654970b19ef7f7d11a0588..bc42afda3094b5a4a49f570f5a5b00764927f912 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.asgn/move.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.asgn/move.pass.cpp
@@ -107,7 +107,7 @@ void test_sfinae() {
 }
 
 
-int main() {
+int main(int, char**) {
   {
     test_basic</*IsArray*/ false>();
     test_sfinae<false>();
@@ -116,4 +116,6 @@ int main() {
     test_basic</*IsArray*/ true>();
     test_sfinae<true>();
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.asgn/move_convert.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.asgn/move_convert.pass.cpp
index b89a452014d5ee1d26d4ca38fa17ba90c0a4c035..c9ebdf63344884dc0856cb1c304a29d95bfdfe86 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.asgn/move_convert.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.asgn/move_convert.pass.cpp
@@ -405,7 +405,7 @@ void test_deleter_value_category() {
   }
 }
 
-int main() {
+int main(int, char**) {
   {
     test_sfinae</*IsArray*/false>();
     test_noexcept<false>();
@@ -416,4 +416,6 @@ int main() {
     test_noexcept<true>();
     test_deleter_value_category<true>();
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.asgn/move_convert.runtime.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.asgn/move_convert.runtime.pass.cpp
index 0800f869fe657a7df39af140052462edbe264a56..ce912546533f7ff461566df39efa44f12c005cf1 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.asgn/move_convert.runtime.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.asgn/move_convert.runtime.pass.cpp
@@ -114,7 +114,9 @@ void test_sfinae() {
   }
 }
 
-int main() {
+int main(int, char**) {
   test_sfinae();
   // FIXME: add tests
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.asgn/move_convert.single.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.asgn/move_convert.single.pass.cpp
index 2b9bdb8c330f762080dfa70a169c11e988e9e350..d5f46935a19ac75319ffbf8c200e707ae5eb44c0 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.asgn/move_convert.single.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.asgn/move_convert.single.pass.cpp
@@ -113,7 +113,7 @@ void test_sfinae() {
   }
 }
 
-int main() {
+int main(int, char**) {
   test_sfinae();
   {
     std::unique_ptr<B> bptr(new B);
@@ -141,4 +141,6 @@ int main() {
   }
   assert(A::count == 0);
   assert(B::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.asgn/null.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.asgn/null.pass.cpp
index 28ea9d7b04db846b81a21d3b1150ea4c8c348190..ecba79dfd3278d21e5bcf9038aee438d9cc0e1c0 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.asgn/null.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.asgn/null.pass.cpp
@@ -32,7 +32,9 @@ void test_basic() {
   assert(A::count == 0);
 }
 
-int main() {
+int main(int, char**) {
   test_basic</*IsArray*/ false>();
   test_basic<true>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.asgn/nullptr.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.asgn/nullptr.pass.cpp
index 91349cb300eccd6dbbbfbe507257cb07668919b6..5cd44b2f64701e54143b1400f9eb3ca8bb7788bb 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.asgn/nullptr.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.asgn/nullptr.pass.cpp
@@ -33,7 +33,9 @@ void test_basic() {
   assert(A::count == 0);
 }
 
-int main() {
+int main(int, char**) {
   test_basic</*IsArray*/ false>();
   test_basic<true>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/auto_pointer.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/auto_pointer.pass.cpp
index e2fe7bb0dd38e6a6888343c5c238b911e4eb1ecb..577a906fb0ef7948045d668a0c35921dfb08d082 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/auto_pointer.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/auto_pointer.pass.cpp
@@ -61,7 +61,7 @@ void test_sfinae() {
   }
 }
 
-int main() {
+int main(int, char**) {
   {
     B* p = new B;
     std::auto_ptr<B> ap(p);
@@ -93,4 +93,6 @@ int main() {
   }
 #endif
   test_sfinae();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/default.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/default.pass.cpp
index 3145c0c9f08305e301ce26edb160837b8d4ed88b..1bd53b9a9ca5e8b9f97d4fd11a6cc7e3ed442954 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/default.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/default.pass.cpp
@@ -94,7 +94,7 @@ DEFINE_AND_RUN_IS_INCOMPLETE_TEST({
   doIncompleteTypeTest<IncompleteType[], Deleter<IncompleteType[]> >(0);
 })
 
-int main() {
+int main(int, char**) {
   {
     test_sfinae<int>();
     test_basic<int>();
@@ -103,4 +103,6 @@ int main() {
     test_sfinae<int[]>();
     test_basic<int[]>();
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/move.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/move.pass.cpp
index f95897b9f927a4a8dc79943966ea64e7bab7b58f..7c07b2ec9845a1c221c3a4e1ed77d4246591ccf5 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/move.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/move.pass.cpp
@@ -159,7 +159,7 @@ void test_noexcept() {
 #endif
 }
 
-int main() {
+int main(int, char**) {
   {
     test_basic</*IsArray*/ false>();
     test_sfinae<int>();
@@ -170,4 +170,6 @@ int main() {
     test_sfinae<int[]>();
     test_noexcept<int[]>();
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/move_convert.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/move_convert.pass.cpp
index f19943a46cc51673612265878aeaee113f56610e..3d0bb1cd1f64cb071774be2ac37066653a5e466e 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/move_convert.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/move_convert.pass.cpp
@@ -204,7 +204,7 @@ void test_deleter_value_category() {
 }
 
 
-int main() {
+int main(int, char**) {
   {
     test_sfinae</*IsArray*/false>();
     test_noexcept<false>();
@@ -215,4 +215,6 @@ int main() {
     test_noexcept<true>();
     test_deleter_value_category<true>();
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/move_convert.runtime.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/move_convert.runtime.pass.cpp
index 010c2293a1603d460e73d8e9fa4f2554bd36ac95..bcf85b11031ec3e0e3be75295fc8ed49021b8cfe 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/move_convert.runtime.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/move_convert.runtime.pass.cpp
@@ -77,6 +77,8 @@ void test_sfinae() {
 }
 
 
-int main() {
+int main(int, char**) {
   test_sfinae();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/move_convert.single.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/move_convert.single.pass.cpp
index d269544c33146505b012889102f9226cb7c5721e..1dcf0cf325c33e9c82b4137b82a7749c194415fb 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/move_convert.single.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/move_convert.single.pass.cpp
@@ -157,7 +157,7 @@ void test_noexcept() {
   }
 }
 
-int main() {
+int main(int, char**) {
   {
     test_sfinae();
     test_noexcept();
@@ -244,4 +244,6 @@ int main() {
     }
     checkNoneAlive();
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/null.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/null.pass.cpp
index e2694b38af815ccf3423e5fdeb72a3185ecceba6..d24538832763f2d05898e16f318036bb7c85e58e 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/null.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/null.pass.cpp
@@ -61,7 +61,7 @@ void test_pointer_deleter_ctor() {
   }
 }
 
-int main() {
+int main(int, char**) {
   {
     // test_pointer_ctor<int>();
     test_pointer_deleter_ctor<int>();
@@ -70,4 +70,6 @@ int main() {
     test_pointer_ctor<int[]>();
     test_pointer_deleter_ctor<int[]>();
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/nullptr.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/nullptr.pass.cpp
index 8d3f94715c88f14e7dcd6b73941bba01b4a009c5..9ec7f7a4e1d9bd806794fee9cb15f88d3662eea9 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/nullptr.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/nullptr.pass.cpp
@@ -93,7 +93,7 @@ DEFINE_AND_RUN_IS_INCOMPLETE_TEST({
   checkNumIncompleteTypeAlive(0);
 })
 
-int main() {
+int main(int, char**) {
   {
     test_basic<int>();
     test_sfinae<int>();
@@ -102,4 +102,6 @@ int main() {
     test_basic<int[]>();
     test_sfinae<int[]>();
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/pointer.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/pointer.pass.cpp
index 55a5f48b2d33fd8790d7ab91564bfef625204134..48d41fc5c0fa441334122f2ee376a2c0b23d7e2a 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/pointer.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/pointer.pass.cpp
@@ -156,7 +156,7 @@ DEFINE_AND_RUN_IS_INCOMPLETE_TEST({
   checkNumIncompleteTypeAlive(0);
 })
 
-int main() {
+int main(int, char**) {
   {
     test_pointer</*IsArray*/ false>();
     test_derived();
@@ -167,4 +167,6 @@ int main() {
     test_sfinae<int[]>();
     test_sfinae_runtime();
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/pointer_deleter.fail.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/pointer_deleter.fail.cpp
index 4c5536d939c0133f3b73a12bc7a65cc5e8464ef4..ccb4924d02409577fa5393f98dd0a21cfcf42285 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/pointer_deleter.fail.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/pointer_deleter.fail.cpp
@@ -22,7 +22,9 @@ struct Deleter {
   void operator()(int* p) const { delete p; }
 };
 
-int main() {
+int main(int, char**) {
   // expected-error@+1 {{call to deleted constructor of 'std::unique_ptr<int, const Deleter &>}}
   std::unique_ptr<int, const Deleter&> s((int*)nullptr, Deleter());
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/pointer_deleter.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/pointer_deleter.pass.cpp
index 246af44f97fbaf335ab6ccc5a8e1364b3be86896..59861effb4eff387f745bf7098229ff37dc55f86 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/pointer_deleter.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/pointer_deleter.pass.cpp
@@ -309,7 +309,7 @@ void test_nullptr() {
 #endif
 }
 
-int main() {
+int main(int, char**) {
   {
     test_basic</*IsArray*/ false>();
     test_nullptr<false>();
@@ -324,4 +324,6 @@ int main() {
     test_sfinae_runtime();
     test_noexcept<true>();
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.dtor/null.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.dtor/null.pass.cpp
index e7b916558998cca82788492ad65aee6fc3f001f5..9ef48b2e4af76aa98c36f9b35ff36014802ebb1d 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.dtor/null.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.dtor/null.pass.cpp
@@ -41,7 +41,9 @@ void test_basic() {
   assert(d.state() == 0);
 }
 
-int main() {
+int main(int, char**) {
   test_basic<int>();
   test_basic<int[]>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.modifiers/release.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.modifiers/release.pass.cpp
index cc2a8366e9d8d6c0dff586138c10ed91f84e6b67..f080165d561ad487830a18f3a0c3542964a4d504 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.modifiers/release.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.modifiers/release.pass.cpp
@@ -49,7 +49,9 @@ void test_basic() {
   assert(A::count == 0);
 }
 
-int main() {
+int main(int, char**) {
   test_basic</*IsArray*/ false>();
   test_basic<true>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.modifiers/reset.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.modifiers/reset.pass.cpp
index f271a7fb47b9b89375c4122aacbacbf19f1aab03..46569918a5f988679b500f6b7ca6879b4fbbf295 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.modifiers/reset.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.modifiers/reset.pass.cpp
@@ -102,7 +102,7 @@ void test_reset_no_arg() {
   assert(A::count == 0);
 }
 
-int main() {
+int main(int, char**) {
   {
     test_reset_pointer</*IsArray*/ false>();
     test_reset_nullptr<false>();
@@ -113,4 +113,6 @@ int main() {
     test_reset_nullptr<true>();
     test_reset_no_arg<true>();
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.modifiers/reset.runtime.fail.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.modifiers/reset.runtime.fail.cpp
index 98a4125ba771acf17a2f871a34856a8be6b83c23..7e3085a5b0fbf6f56b2837a891840f56a988af4f 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.modifiers/reset.runtime.fail.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.modifiers/reset.runtime.fail.cpp
@@ -17,7 +17,7 @@
 
 #include "unique_ptr_test_helper.h"
 
-int main() {
+int main(int, char**) {
   {
     std::unique_ptr<A[]> p;
     p.reset(static_cast<B*>(nullptr)); // expected-error {{no matching member function for call to 'reset'}}
@@ -26,4 +26,6 @@ int main() {
     std::unique_ptr<int[]> p;
     p.reset(static_cast<const int*>(nullptr)); // expected-error {{no matching member function for call to 'reset'}}
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.modifiers/reset.single.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.modifiers/reset.single.pass.cpp
index e9d43b6024767448c39fa359f685adbb98b3f890..4f5a519b798ba41a0d2e9d675dcefc6181be9c80 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.modifiers/reset.single.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.modifiers/reset.single.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "unique_ptr_test_helper.h"
 
-int main() {
+int main(int, char**) {
   {
     std::unique_ptr<A> p(new A);
     assert(A::count == 1);
@@ -42,4 +42,6 @@ int main() {
   }
   assert(A::count == 0);
   assert(B::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.modifiers/reset_self.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.modifiers/reset_self.pass.cpp
index 129e3ea45b1df9fbdd2ee7ec06c45f7e4c874fb0..d5e15aafe24c830e96715d28e34d8893b131029e 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.modifiers/reset_self.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.modifiers/reset_self.pass.cpp
@@ -21,4 +21,6 @@ struct A {
   void reset() { ptr_.reset(); }
 };
 
-int main() { (new A)->reset(); }
+int main(int, char**) { (new A)->reset(); 
+  return 0;
+}
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.modifiers/swap.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.modifiers/swap.pass.cpp
index 935ebab7fda38c0bd372898a704bc7580a252ee7..35e997e30659f3de957390ca32069dcce1698c2b 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.modifiers/swap.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.modifiers/swap.pass.cpp
@@ -81,7 +81,9 @@ void test_basic() {
   assert(TT::count == 0);
 }
 
-int main() {
+int main(int, char**) {
   test_basic</*IsArray*/ false>();
   test_basic<true>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/dereference.runtime.fail.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/dereference.runtime.fail.cpp
index 0fd37cbfa062ea86036906ad79379d66a5dc7bec..8a5566b915c0f711fd6af1c9cfe0b4f4de93242e 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/dereference.runtime.fail.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/dereference.runtime.fail.cpp
@@ -15,9 +15,11 @@
 #include <memory>
 #include <cassert>
 
-int main() {
+int main(int, char**) {
   std::unique_ptr<int[]> p(new int(3));
   const std::unique_ptr<int[]>& cp = p;
   TEST_IGNORE_NODISCARD (*p);  // expected-error {{indirection requires pointer operand ('std::unique_ptr<int []>' invalid)}}
   TEST_IGNORE_NODISCARD (*cp); // expected-error {{indirection requires pointer operand ('const std::unique_ptr<int []>' invalid)}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/dereference.single.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/dereference.single.pass.cpp
index 49cfccb6f85d79950ff33d1020b1ac9cb84019ab..254d88bb6cf66e563ab5ea113e751364c492089f 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/dereference.single.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/dereference.single.pass.cpp
@@ -15,7 +15,9 @@
 #include <memory>
 #include <cassert>
 
-int main() {
+int main(int, char**) {
   std::unique_ptr<int> p(new int(3));
   assert(*p == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/explicit_bool.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/explicit_bool.pass.cpp
index ce45882a8bf1b5851b76d653c1c43f8452fb1888..500821fb8175b1d038c1d63d2f0acbcd4cea91a4 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/explicit_bool.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/explicit_bool.pass.cpp
@@ -59,7 +59,9 @@ void test_basic() {
   }
 }
 
-int main() {
+int main(int, char**) {
   test_basic</*IsArray*/ false>();
   test_basic<true>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/get.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/get.pass.cpp
index 76f2b4c67129a8bbcf979fd809175bbe9193c5ab..1ff965f563e12ca27325e21b377d3b50b6ce4565 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/get.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/get.pass.cpp
@@ -44,7 +44,9 @@ void test_basic() {
   }
 }
 
-int main() {
+int main(int, char**) {
   test_basic</*IsArray*/ false>();
   test_basic<true>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/get_deleter.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/get_deleter.pass.cpp
index 31f33a265c67a6ce9f57c49c84fe4480e22b14cd..e440a95991c723f28f44f3b545a057b3733f0756 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/get_deleter.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/get_deleter.pass.cpp
@@ -58,7 +58,9 @@ void test_basic() {
   }
 }
 
-int main() {
+int main(int, char**) {
   test_basic</*IsArray*/ false>();
   test_basic<true>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/op_arrow.runtime.fail.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/op_arrow.runtime.fail.cpp
index 886fc95d9deeab40ed6c69ced04aa35a9be827ee..4fa94f137ce8e190a31a707f3374931c5ccb4a76 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/op_arrow.runtime.fail.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/op_arrow.runtime.fail.cpp
@@ -19,7 +19,7 @@ struct V {
   int member;
 };
 
-int main() {
+int main(int, char**) {
   std::unique_ptr<V[]> p;
   std::unique_ptr<V[]> const& cp = p;
 
@@ -28,4 +28,6 @@ int main() {
 
   cp->member; // expected-error {{member reference type 'const std::unique_ptr<V []>' is not a pointer}}
               // expected-error@-1 {{no member named 'member'}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/op_arrow.single.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/op_arrow.single.pass.cpp
index 0bc0c7718b800609554011f40921b431af3abf9b..f31ca6b286d12b34b7232295128cbae672ddbfa0 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/op_arrow.single.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/op_arrow.single.pass.cpp
@@ -21,7 +21,9 @@ struct A {
   A() : i_(7) {}
 };
 
-int main() {
+int main(int, char**) {
   std::unique_ptr<A> p(new A);
   assert(p->i_ == 7);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/op_subscript.runtime.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/op_subscript.runtime.pass.cpp
index 2b97f8fe5694651a1828c0335adf589440c0804a..21e7e661688ab5a53b22f8925cfa8d888d3230d0 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/op_subscript.runtime.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/op_subscript.runtime.pass.cpp
@@ -33,7 +33,7 @@ public:
 
 int A::next_ = 0;
 
-int main() {
+int main(int, char**) {
   std::unique_ptr<A[]> p(new A[3]);
   assert(p[0] == 1);
   assert(p[1] == 2);
@@ -44,4 +44,6 @@ int main() {
   assert(p[0] == 3);
   assert(p[1] == 2);
   assert(p[2] == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/op_subscript.single.fail.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/op_subscript.single.fail.cpp
index e5a960a6e804c754c202721cb4d76ce1c2a14499..66286aa862088c0a3c3e532854a99073725d7fe4 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/op_subscript.single.fail.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.observers/op_subscript.single.fail.cpp
@@ -15,9 +15,11 @@
 #include <memory>
 #include <cassert>
 
-int main() {
+int main(int, char**) {
   std::unique_ptr<int> p(new int[3]);
   std::unique_ptr<int> const& cp = p;
   p[0];  // expected-error {{type 'std::unique_ptr<int>' does not provide a subscript operator}}
   cp[1]; // expected-error {{type 'const std::unique_ptr<int>' does not provide a subscript operator}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.create/make_unique.array.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.create/make_unique.array.pass.cpp
index a77194ecf95e52b3438479ba1b6d06f474a89113..715335eb1cd06666ba0a99b99a42aec77df44ebc 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.create/make_unique.array.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.create/make_unique.array.pass.cpp
@@ -21,7 +21,7 @@ private:
     int val_;
     };
 
-int main()
+int main(int, char**)
 {
     {
     auto p1 = std::make_unique<int[]>(5);
@@ -40,4 +40,6 @@ int main()
     for ( int i = 0; i < 7; ++i )
         assert ( p3[i].get () == 3 );
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.create/make_unique.array1.fail.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.create/make_unique.array1.fail.cpp
index a0e256fcf1e62adf38eb35f7b7e3c877a24a2d62..56adccf176af9ed7b4bd8a4a447ac464a8737997 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.create/make_unique.array1.fail.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.create/make_unique.array1.fail.cpp
@@ -10,7 +10,9 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     auto up1 = std::make_unique<std::string[]>("error"); // doesn't compile - no bound
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.create/make_unique.array2.fail.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.create/make_unique.array2.fail.cpp
index 0f366c6c3e2badec1abf47db2656a50fc16ab354..fda45ab8946115d46903b347808c6f73083c3ed5 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.create/make_unique.array2.fail.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.create/make_unique.array2.fail.cpp
@@ -10,7 +10,9 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     auto up2 = std::make_unique<int[]>(10, 20, 30, 40);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.create/make_unique.array3.fail.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.create/make_unique.array3.fail.cpp
index 90622fed107917262bbde3c97123634701f96311..9fa05c79d93fcc02f2a751911e04540dfbb0634e 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.create/make_unique.array3.fail.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.create/make_unique.array3.fail.cpp
@@ -10,7 +10,9 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     auto up3 = std::make_unique<int[5]>();    // this is deleted
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.create/make_unique.array4.fail.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.create/make_unique.array4.fail.cpp
index 5c10ac6bb24ffb1ebe825cca76b3fdce7a3dbcb1..d98f052b54ff732789cb57b4d154ad0455d5757a 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.create/make_unique.array4.fail.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.create/make_unique.array4.fail.cpp
@@ -10,7 +10,9 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     auto up4 = std::make_unique<int[5]>(11, 22, 33, 44, 55); // deleted
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.create/make_unique.single.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.create/make_unique.single.pass.cpp
index 4adf2e9ae4205a0c9d17ff0b90d4efc90665bc88..08062c122e1859d7fa9b3886212772a67a79ea94 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.create/make_unique.single.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.create/make_unique.single.pass.cpp
@@ -11,7 +11,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
     std::unique_ptr<int> p1 = std::make_unique<int>(1);
@@ -28,4 +28,6 @@ int main()
     p2 = std::make_unique<std::string> ( 6, 'z' );
     assert ( *p2 == "zzzzzz" );
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt/convert_ctor.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt/convert_ctor.pass.cpp
index 85605a2fc429494dce1b568b8c4436ff48db0105..6b8407c571a4ed1d5ea5f5eb2e1e59766973a633 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt/convert_ctor.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt/convert_ctor.pass.cpp
@@ -34,7 +34,7 @@ struct B
 
 int B::count = 0;
 
-int main()
+int main(int, char**)
 {
     std::default_delete<B> d2;
     std::default_delete<A> d1 = d2;
@@ -44,4 +44,6 @@ int main()
     d1(p);
     assert(A::count == 0);
     assert(B::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt/default.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt/default.pass.cpp
index c0a10e5e3ebe54902829f3672a73c19733a0fede..e7cbeaba5e0c1379ab6831eb16e6bb880f676abd 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt/default.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt/default.pass.cpp
@@ -23,11 +23,13 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     std::default_delete<A> d;
     A* p = new A;
     assert(A::count == 1);
     d(p);
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt/incomplete.fail.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt/incomplete.fail.cpp
index b09640215a28c6a6087d6d5419db0b431b0dea79..75f02d7c6c6fd6950a0b9ed8f19c11b7a3b6ea42 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt/incomplete.fail.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt/incomplete.fail.cpp
@@ -17,9 +17,11 @@
 
 struct A;
 
-int main()
+int main(int, char**)
 {
     std::default_delete<A> d;
     A* p = 0;
     d(p);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt/void.fail.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt/void.fail.cpp
index d03468c03800c8c45a8b6a8c15e711f27ef44280..3bffeb5769497cfb1ddf5cc46c0f1f1d6adb0df8 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt/void.fail.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt/void.fail.cpp
@@ -15,9 +15,11 @@
 #include <memory>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::default_delete<const void> d;
     const void* p = 0;
     d(p);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt1/convert_ctor.fail.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt1/convert_ctor.fail.cpp
index 699d20ed4f7de2e2a1e9f8e7e1d747ab3face61d..4a2bb5f7da77fe2b67bc566854e9c35baa17795e 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt1/convert_ctor.fail.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt1/convert_ctor.fail.cpp
@@ -24,8 +24,10 @@ struct B
 {
 };
 
-int main()
+int main(int, char**)
 {
     std::default_delete<B[]> d2;
     std::default_delete<A[]> d1 = d2;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt1/convert_ctor.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt1/convert_ctor.pass.cpp
index c2bfd31de1ce48e42ac9752ef81dc393624a2046..14e210598c11a64bca837d01ea59dd4fb3027400 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt1/convert_ctor.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt1/convert_ctor.pass.cpp
@@ -19,9 +19,11 @@
 #include <memory>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::default_delete<int[]> d1;
     std::default_delete<const int[]> d2 = d1;
     ((void)d2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt1/default.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt1/default.pass.cpp
index 246cf9d8dc589ee1feda25d1338485958e9f2761..9b220462b67d04e3a7147de11f64d2768f0a4725 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt1/default.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt1/default.pass.cpp
@@ -25,11 +25,13 @@ struct A
 
 int A::count = 0;
 
-int main()
+int main(int, char**)
 {
     std::default_delete<A[]> d;
     A* p = new A[3];
     assert(A::count == 3);
     d(p);
     assert(A::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt1/incomplete.fail.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt1/incomplete.fail.cpp
index 48ac045526eda3d8b3d6d7d858b1215566f84e10..54fe0fcf793b99167d6417a8c7f3ca9920149430 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt1/incomplete.fail.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.dflt1/incomplete.fail.cpp
@@ -17,9 +17,11 @@
 
 struct A;
 
-int main()
+int main(int, char**)
 {
     std::default_delete<A[]> d;
     A* p = 0;
     d(p);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.general/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.general/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.general/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.dltr/unique.ptr.dltr.general/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.special/cmp_nullptr.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.special/cmp_nullptr.pass.cpp
index 774bc62d21bb9fda5a855739229fada7a9c9100a..52c399e64f721e0817a92a752c96c5045a0a9290 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.special/cmp_nullptr.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.special/cmp_nullptr.pass.cpp
@@ -40,7 +40,7 @@
 
 void do_nothing(int*) {}
 
-int main()
+int main(int, char**)
 {
     const std::unique_ptr<int> p1(new int(1));
     assert(!(p1 == nullptr));
@@ -65,4 +65,6 @@ int main()
     assert(!(nullptr > p2));
     assert( (p2 >= nullptr));
     assert( (nullptr >= p2));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.special/eq.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.special/eq.pass.cpp
index e1f3e762d6928df4e9324d2375db07be0e599d11..ce83b575031e663734046397acccc4c38f554951 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.special/eq.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.special/eq.pass.cpp
@@ -44,7 +44,7 @@ struct B
 
 int B::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
     const std::unique_ptr<A, Deleter<A> > p1(new A);
@@ -82,4 +82,6 @@ int main()
     assert(p1 == p2);
     assert(!(p1 != p2));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.special/rel.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.special/rel.pass.cpp
index 167dd7826c5ef9b95cd01630d56ff846c2a1046f..5fad4beb6c6eacc4aab3e295840ed69bc651c399 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.special/rel.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.special/rel.pass.cpp
@@ -52,7 +52,7 @@ struct B
 
 int B::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
     const std::unique_ptr<A, Deleter<A> > p1(new A);
@@ -96,4 +96,6 @@ int main()
     assert((p1 < p2) == !(p1 <= p2));
     assert((p1 < p2) == !(p1 >= p2));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.special/swap.pass.cpp b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.special/swap.pass.cpp
index 67cb170e4f9f31eef990dc4c046229eb1d2bd0d9..4e45bbaef355ea941bc18f9597784bca02abaf66 100644
--- a/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.special/swap.pass.cpp
+++ b/libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.special/swap.pass.cpp
@@ -44,7 +44,7 @@ private:
 
 };
 
-int main()
+int main(int, char**)
 {
     {
     A* p1 = new A(1);
@@ -98,4 +98,6 @@ int main()
         std::swap(p, p2);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.cons/char_ptr_ctor.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.cons/char_ptr_ctor.pass.cpp
index 8219296523bdcc046df549a9a2ac08f7e32a6891..ee6405bde1e724ad01382668fcd70b24fbc701ad 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.cons/char_ptr_ctor.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.cons/char_ptr_ctor.pass.cpp
@@ -46,7 +46,7 @@ void test_char_pointer_ctor()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test_char_pointer_ctor<0>();
     test_char_pointer_ctor<1>();
@@ -57,4 +57,6 @@ int main()
     test_char_pointer_ctor<64>();
     test_char_pointer_ctor<65>();
     test_char_pointer_ctor<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.cons/default.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.cons/default.pass.cpp
index 0c88ba36ab69ff82f2da2d7b690451dca04313da..bb5de6b18c72ff8c75c2dea33bd55340a7216c55 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.cons/default.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.cons/default.pass.cpp
@@ -35,7 +35,7 @@ void test_default_ctor()
 }
 
 
-int main()
+int main(int, char**)
 {
     test_default_ctor<0>();
     test_default_ctor<1>();
@@ -46,4 +46,6 @@ int main()
     test_default_ctor<64>();
     test_default_ctor<65>();
     test_default_ctor<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.cons/string_ctor.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.cons/string_ctor.pass.cpp
index f5052b5efbb4493ecc3ed814029373e24a6f2b1d..453db91f29db57fbeef6bb196cedc741dc1d8708 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.cons/string_ctor.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.cons/string_ctor.pass.cpp
@@ -74,7 +74,7 @@ void test_string_ctor()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test_string_ctor<0>();
     test_string_ctor<1>();
@@ -85,4 +85,6 @@ int main()
     test_string_ctor<64>();
     test_string_ctor<65>();
     test_string_ctor<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.cons/ull_ctor.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.cons/ull_ctor.pass.cpp
index a09ce57e34657136804c4d5a847ef9777ab2d7f7..4697d8bd380a48994d68baf0b968a706c4d626da 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.cons/ull_ctor.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.cons/ull_ctor.pass.cpp
@@ -39,7 +39,7 @@ void test_val_ctor()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test_val_ctor<0>();
     test_val_ctor<1>();
@@ -50,4 +50,6 @@ int main()
     test_val_ctor<64>();
     test_val_ctor<65>();
     test_val_ctor<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.hash/bitset.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.hash/bitset.pass.cpp
index 95347a2bc53de59f10e97891d04fd8b321a518a9..dfac9d94af7c72c36b4909b1be2e744714e4b200 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.hash/bitset.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.hash/bitset.pass.cpp
@@ -38,10 +38,12 @@ test()
     ((void)result); // Prevent unused warning
 }
 
-int main()
+int main(int, char**)
 {
     test<0>();
     test<10>();
     test<100>();
     test<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.hash/enabled_hash.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.hash/enabled_hash.pass.cpp
index 05d286f9058cf0de986f0099a59859fb2df5f04e..a499b66fdb584aec9aaff9fd1ba7d8961803707e 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.hash/enabled_hash.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.hash/enabled_hash.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "poisoned_hash_helper.hpp"
 
-int main() {
+int main(int, char**) {
   test_library_hash_specializations_available();
   {
     test_hash_enabled_for_type<std::bitset<0> >();
@@ -25,4 +25,6 @@ int main() {
     test_hash_enabled_for_type<std::bitset<1024> >();
     test_hash_enabled_for_type<std::bitset<100000> >();
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/all.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/all.pass.cpp
index 4ac3bae75a8e334db7ba1eeb44fa2dc0488dc797..fe9e0e0a363b6593d49dde9b996569a60d0cce93 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.members/all.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/all.pass.cpp
@@ -28,7 +28,7 @@ void test_all()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test_all<0>();
     test_all<1>();
@@ -39,4 +39,6 @@ int main()
     test_all<64>();
     test_all<65>();
     test_all<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/any.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/any.pass.cpp
index 0483a04ffa2a8e0f772953fb70555b4dd67cb8a7..95b640178b973a25d1a3792834f50f25177f3249 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.members/any.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/any.pass.cpp
@@ -31,7 +31,7 @@ void test_any()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test_any<0>();
     test_any<1>();
@@ -42,4 +42,6 @@ int main()
     test_any<64>();
     test_any<65>();
     test_any<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/count.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/count.pass.cpp
index 9b66e93e25feab71c269efec0357af6953af27e5..5b04666bc2aeb51b3b1676aa422dbdeb25fa7a77 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.members/count.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/count.pass.cpp
@@ -42,7 +42,7 @@ void test_count()
     assert(c1 == c2);
 }
 
-int main()
+int main(int, char**)
 {
     test_count<0>();
     test_count<1>();
@@ -53,4 +53,6 @@ int main()
     test_count<64>();
     test_count<65>();
     test_count<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/flip_all.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/flip_all.pass.cpp
index b3f515c0c3f4119d7e93bd5becb1df6f6223ce4a..14bd9eadf98a5d138e47dd51ae738bc0512d5abc 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.members/flip_all.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/flip_all.pass.cpp
@@ -40,7 +40,7 @@ void test_flip_all()
         assert(v2[i] == ~v1[i]);
 }
 
-int main()
+int main(int, char**)
 {
     test_flip_all<0>();
     test_flip_all<1>();
@@ -51,4 +51,6 @@ int main()
     test_flip_all<64>();
     test_flip_all<65>();
     test_flip_all<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/flip_one.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/flip_one.pass.cpp
index 96569e565e6242146067822334c4ea8ee4a7d088..235b7e1a7aecf21ec3f2db132146ffca4afe69d4 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.members/flip_one.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/flip_one.pass.cpp
@@ -58,7 +58,7 @@ void test_flip_one(bool test_throws)
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test_flip_one<0>(true);
     test_flip_one<1>(true);
@@ -69,4 +69,6 @@ int main()
     test_flip_one<64>(false);
     test_flip_one<65>(false);
     test_flip_one<1000>(false);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/index.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/index.pass.cpp
index fb68df5aa38bc785261c5be608e113cf9d7b0516..a6eea1450074afbfa88afb152ccb044f25ba7063 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.members/index.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/index.pass.cpp
@@ -60,7 +60,7 @@ void test_index_const()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test_index_const<0>();
     test_index_const<1>();
@@ -71,4 +71,6 @@ int main()
     test_index_const<64>();
     test_index_const<65>();
     test_index_const<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/index_const.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/index_const.pass.cpp
index 54a1a31c0dbc7d50b06c8345755f71ff0a13b15c..9c6e28a88948a46f349a19a30603482056e686a5 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.members/index_const.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/index_const.pass.cpp
@@ -42,7 +42,7 @@ void test_index_const()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test_index_const<0>();
     test_index_const<1>();
@@ -53,4 +53,6 @@ int main()
     test_index_const<64>();
     test_index_const<65>();
     test_index_const<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/left_shift.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/left_shift.pass.cpp
index 27a20b4f64acd664bac8cbe07c67e14780098fb2..59a7954a0df2666aabab06d927a8cc3c432f9d7d 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.members/left_shift.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/left_shift.pass.cpp
@@ -41,7 +41,7 @@ void test_left_shift()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test_left_shift<0>();
     test_left_shift<1>();
@@ -52,4 +52,6 @@ int main()
     test_left_shift<64>();
     test_left_shift<65>();
     test_left_shift<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/left_shift_eq.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/left_shift_eq.pass.cpp
index c3becacd333ba81cccd98433297bd1e0a9d16184..ad307ae826282650ca90467be6b135828deb6458 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.members/left_shift_eq.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/left_shift_eq.pass.cpp
@@ -46,7 +46,7 @@ void test_left_shift()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test_left_shift<0>();
     test_left_shift<1>();
@@ -57,4 +57,6 @@ int main()
     test_left_shift<64>();
     test_left_shift<65>();
     test_left_shift<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/none.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/none.pass.cpp
index d5004fbb68664fa92b314c849da2703c85900dae..2588ac60f7b371b88ea98e7aa7fddd9c980f6a15 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.members/none.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/none.pass.cpp
@@ -31,7 +31,7 @@ void test_none()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test_none<0>();
     test_none<1>();
@@ -42,4 +42,6 @@ int main()
     test_none<64>();
     test_none<65>();
     test_none<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/not_all.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/not_all.pass.cpp
index 87c3efd1fc3352a7a2d9309109ed190ba30ac61c..17b2d4293ac2abd33999f755e91b4b2ed1584691 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.members/not_all.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/not_all.pass.cpp
@@ -39,7 +39,7 @@ void test_not_all()
         assert(v2[i] == ~v1[i]);
 }
 
-int main()
+int main(int, char**)
 {
     test_not_all<0>();
     test_not_all<1>();
@@ -50,4 +50,6 @@ int main()
     test_not_all<64>();
     test_not_all<65>();
     test_not_all<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/op_and_eq.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/op_and_eq.pass.cpp
index 38564bba5f82eeb60dd91888dfb98f8697ed4ce6..8560be2467e435fb7befba0c99f09ae6ea43a736 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.members/op_and_eq.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/op_and_eq.pass.cpp
@@ -41,7 +41,7 @@ void test_op_and_eq()
         assert(v1[i] == (v3[i] && v2[i]));
 }
 
-int main()
+int main(int, char**)
 {
     test_op_and_eq<0>();
     test_op_and_eq<1>();
@@ -52,4 +52,6 @@ int main()
     test_op_and_eq<64>();
     test_op_and_eq<65>();
     test_op_and_eq<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/op_eq_eq.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/op_eq_eq.pass.cpp
index 7c428bce061c73c4501109b6f4e074b0cba3e31c..d2363023e62989550c7368b8a30a068f236cd27b 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.members/op_eq_eq.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/op_eq_eq.pass.cpp
@@ -48,7 +48,7 @@ void test_equality()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test_equality<0>();
     test_equality<1>();
@@ -59,4 +59,6 @@ int main()
     test_equality<64>();
     test_equality<65>();
     test_equality<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/op_or_eq.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/op_or_eq.pass.cpp
index f96c77bc2e68bb6d0766ab5e21232b81df0fc9b4..42d525e5b49e7d04c0448ca9f7d28f2383f1a351 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.members/op_or_eq.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/op_or_eq.pass.cpp
@@ -41,7 +41,7 @@ void test_op_or_eq()
         assert(v1[i] == (v3[i] || v2[i]));
 }
 
-int main()
+int main(int, char**)
 {
     test_op_or_eq<0>();
     test_op_or_eq<1>();
@@ -52,4 +52,6 @@ int main()
     test_op_or_eq<64>();
     test_op_or_eq<65>();
     test_op_or_eq<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/op_xor_eq.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/op_xor_eq.pass.cpp
index 647c5c028befd47375f6c3fbbb9d8b57b7321c73..44d58d8a155016e4577d3e4e5f4c0775d8d45c63 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.members/op_xor_eq.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/op_xor_eq.pass.cpp
@@ -41,7 +41,7 @@ void test_op_xor_eq()
         assert(v1[i] == (v3[i] != v2[i]));
 }
 
-int main()
+int main(int, char**)
 {
     test_op_xor_eq<0>();
     test_op_xor_eq<1>();
@@ -52,4 +52,6 @@ int main()
     test_op_xor_eq<64>();
     test_op_xor_eq<65>();
     test_op_xor_eq<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/reset_all.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/reset_all.pass.cpp
index ae43bd7e99fb09303d4d9d75d787860d58abe415..91041176ddb90ce12aad503991fb27250baf20cc 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.members/reset_all.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/reset_all.pass.cpp
@@ -29,7 +29,7 @@ void test_reset_all()
         assert(!v[i]);
 }
 
-int main()
+int main(int, char**)
 {
     test_reset_all<0>();
     test_reset_all<1>();
@@ -40,4 +40,6 @@ int main()
     test_reset_all<64>();
     test_reset_all<65>();
     test_reset_all<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/reset_one.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/reset_one.pass.cpp
index ec92f6656b32c6c2dd1a64a1fd6ef6e81a670eb9..1abb4914bfa301f8d6415e374de10fe64eb026a3 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.members/reset_one.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/reset_one.pass.cpp
@@ -43,7 +43,7 @@ void test_reset_one(bool test_throws)
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test_reset_one<0>(true);
     test_reset_one<1>(true);
@@ -54,4 +54,6 @@ int main()
     test_reset_one<64>(false);
     test_reset_one<65>(false);
     test_reset_one<1000>(false);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/right_shift.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/right_shift.pass.cpp
index a94f9bf0921aefb33dfaecaa187aa17e80550cc1..e05c3316bb5e56628c55a612dc2ec392c03e34bd 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.members/right_shift.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/right_shift.pass.cpp
@@ -41,7 +41,7 @@ void test_right_shift()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test_right_shift<0>();
     test_right_shift<1>();
@@ -52,4 +52,6 @@ int main()
     test_right_shift<64>();
     test_right_shift<65>();
     test_right_shift<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/right_shift_eq.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/right_shift_eq.pass.cpp
index 387f68249e3309dcdf465839a85f6f9954be1af6..f23fbeebc878766fe0dcc2b534e311a21a37acb3 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.members/right_shift_eq.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/right_shift_eq.pass.cpp
@@ -46,7 +46,7 @@ void test_right_shift()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test_right_shift<0>();
     test_right_shift<1>();
@@ -57,4 +57,6 @@ int main()
     test_right_shift<64>();
     test_right_shift<65>();
     test_right_shift<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/set_all.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/set_all.pass.cpp
index 68f8c58bb2c44ee9791b387b7adb99fb1b9ce6ae..ca4708cc43e12491862e8716414b4aa5757c2e1a 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.members/set_all.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/set_all.pass.cpp
@@ -28,7 +28,7 @@ void test_set_all()
         assert(v[i]);
 }
 
-int main()
+int main(int, char**)
 {
     test_set_all<0>();
     test_set_all<1>();
@@ -39,4 +39,6 @@ int main()
     test_set_all<64>();
     test_set_all<65>();
     test_set_all<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/set_one.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/set_one.pass.cpp
index f660a440947f6e6d7e48c0f50cda8183160c3543..f723eebe08515dd908955e9e2b78ccc17a3de095 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.members/set_one.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/set_one.pass.cpp
@@ -52,7 +52,7 @@ void test_set_one(bool test_throws)
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test_set_one<0>(true);
     test_set_one<1>(true);
@@ -63,4 +63,6 @@ int main()
     test_set_one<64>(false);
     test_set_one<65>(false);
     test_set_one<1000>(false);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/size.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/size.pass.cpp
index f1719ab2e4162a41b8b9bb539dd79c0f26f08a3c..41318d99eef88ac1f4964aa45a75cf0c212e547e 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.members/size.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/size.pass.cpp
@@ -18,7 +18,7 @@ void test_size()
     assert(v.size() == N);
 }
 
-int main()
+int main(int, char**)
 {
     test_size<0>();
     test_size<1>();
@@ -29,4 +29,6 @@ int main()
     test_size<64>();
     test_size<65>();
     test_size<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/test.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/test.pass.cpp
index df3ee16be7e15d8ab23645c7a98d61b4a8a24df9..5d566f5d0cf19dd76878a21384a1ed40d05c4426 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.members/test.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/test.pass.cpp
@@ -53,7 +53,7 @@ void test_test(bool test_throws)
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test_test<0>(true);
     test_test<1>(true);
@@ -64,4 +64,6 @@ int main()
     test_test<64>(false);
     test_test<65>(false);
     test_test<1000>(false);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/to_string.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/to_string.pass.cpp
index d897944729651fec2fd3937a60df996c3c105dd0..3897e10375f7eaed6bea8a9091428e0e47590566 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.members/to_string.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/to_string.pass.cpp
@@ -153,7 +153,7 @@ void test_to_string()
 }
 }
 
-int main()
+int main(int, char**)
 {
     test_to_string<0>();
     test_to_string<1>();
@@ -164,4 +164,6 @@ int main()
     test_to_string<64>();
     test_to_string<65>();
     test_to_string<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/to_ullong.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/to_ullong.pass.cpp
index 1ea9b0f81f1554afe0da1d334ff2464029275d38..c43ef90aeefbeed169d9219a0eb9151ff0b750c7 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.members/to_ullong.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/to_ullong.pass.cpp
@@ -44,7 +44,7 @@ void test_to_ullong()
     }
 }
 
-int main()
+int main(int, char**)
 {
 //     test_to_ullong<0>();
     test_to_ullong<1>();
@@ -55,4 +55,6 @@ int main()
     test_to_ullong<64>();
     test_to_ullong<65>();
     test_to_ullong<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/to_ulong.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/to_ulong.pass.cpp
index 71910f322b28f5e6d0dc488d934c1e3d558a93a4..c6cf6b19a185105785a6df60f765cf98eb6b125c 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.members/to_ulong.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/to_ulong.pass.cpp
@@ -46,7 +46,7 @@ void test_to_ulong()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test_to_ulong<0>();
     test_to_ulong<1>();
@@ -57,4 +57,6 @@ int main()
     test_to_ulong<64>();
     test_to_ulong<65>();
     test_to_ulong<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.operators/op_and.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.operators/op_and.pass.cpp
index af69d3951b746f5c03428fa6bd3de0b96061b277..21d5d08058ca74661f4f9694476afd2b07fe0eef 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.operators/op_and.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.operators/op_and.pass.cpp
@@ -39,7 +39,7 @@ void test_op_and()
     assert((v1 & v2) == (v3 &= v2));
 }
 
-int main()
+int main(int, char**)
 {
     test_op_and<0>();
     test_op_and<1>();
@@ -50,4 +50,6 @@ int main()
     test_op_and<64>();
     test_op_and<65>();
     test_op_and<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.operators/op_not.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.operators/op_not.pass.cpp
index 8d9b2bdfb29d4cafe74859ca2fe3971072cdad0b..4a71385a941fa36d49ccfd6ab7538b8bdad26baa 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.operators/op_not.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.operators/op_not.pass.cpp
@@ -39,7 +39,7 @@ void test_op_not()
     assert((v1 ^ v2) == (v3 ^= v2));
 }
 
-int main()
+int main(int, char**)
 {
     test_op_not<0>();
     test_op_not<1>();
@@ -50,4 +50,6 @@ int main()
     test_op_not<64>();
     test_op_not<65>();
     test_op_not<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.operators/op_or.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.operators/op_or.pass.cpp
index c2cada15ea15fcdb9e93692077ce416a99efc6ca..bc4847c19e409d81ad95aa55f57c6d37b1e6ac71 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.operators/op_or.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.operators/op_or.pass.cpp
@@ -39,7 +39,7 @@ void test_op_or()
     assert((v1 | v2) == (v3 |= v2));
 }
 
-int main()
+int main(int, char**)
 {
     test_op_or<0>();
     test_op_or<1>();
@@ -50,4 +50,6 @@ int main()
     test_op_or<64>();
     test_op_or<65>();
     test_op_or<1000>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.operators/stream_in.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.operators/stream_in.pass.cpp
index 714fcd3ed2fb63dda59cbe4632ca5eefc2a55e48..9abe19c7c87aae9218ec0645a95f0236db701f4b 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.operators/stream_in.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.operators/stream_in.pass.cpp
@@ -16,10 +16,12 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::istringstream in("01011010");
     std::bitset<8> b;
     in >> b;
     assert(b.to_ulong() == 0x5A);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.operators/stream_out.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.operators/stream_out.pass.cpp
index 06a36604ac485957be9a350acdc744b1b75192ae..2c4ce1e48817e37f826e2605dad39e7ef1dd4804 100644
--- a/libcxx/test/std/utilities/template.bitset/bitset.operators/stream_out.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/bitset.operators/stream_out.pass.cpp
@@ -16,10 +16,12 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::ostringstream os;
     std::bitset<8> b(0x5A);
     os << b;
     assert(os.str() == "01011010");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/template.bitset/includes.pass.cpp b/libcxx/test/std/utilities/template.bitset/includes.pass.cpp
index c98b150e792aaaef9ab7d45584a3f1622c0672b1..90695ed3dccc521b57fd13922c0e723b0a72a4de 100644
--- a/libcxx/test/std/utilities/template.bitset/includes.pass.cpp
+++ b/libcxx/test/std/utilities/template.bitset/includes.pass.cpp
@@ -12,7 +12,7 @@
 
 template <class> void test_typedef() {}
 
-int main()
+int main(int, char**)
 {
   { // test for <string>
     std::string s; ((void)s);
@@ -24,4 +24,6 @@ int main()
     test_typedef<std::ostream>();
     test_typedef<std::iostream>();
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/date.time/ctime.pass.cpp b/libcxx/test/std/utilities/time/date.time/ctime.pass.cpp
index 3fa04b7799965184d9aacfde7955142a0fd6b967..ac29fd78180494dac737584932b759847c213113 100644
--- a/libcxx/test/std/utilities/time/date.time/ctime.pass.cpp
+++ b/libcxx/test/std/utilities/time/date.time/ctime.pass.cpp
@@ -29,7 +29,7 @@
 #pragma GCC diagnostic ignored "-Wformat-zero-length"
 #endif
 
-int main()
+int main(int, char**)
 {
     std::clock_t c = 0;
     std::size_t s = 0;
@@ -60,4 +60,6 @@ int main()
     static_assert((std::is_same<decltype(std::localtime(&t)), std::tm*>::value), "");
 #endif
     static_assert((std::is_same<decltype(std::strftime(str,s,"",&tm)), std::size_t>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/days.pass.cpp b/libcxx/test/std/utilities/time/days.pass.cpp
index a22f97b8f527fab726a47fa9fabcde76407f3b3a..43b53ea33cb8972a420d5ba04c00810bda3c18fe 100644
--- a/libcxx/test/std/utilities/time/days.pass.cpp
+++ b/libcxx/test/std/utilities/time/days.pass.cpp
@@ -15,7 +15,7 @@
 #include <type_traits>
 #include <limits>
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::days D;
     typedef D::rep Rep;
@@ -24,4 +24,6 @@ int main()
     static_assert(std::is_integral<Rep>::value, "");
     static_assert(std::numeric_limits<Rep>::digits >= 25, "");
     static_assert(std::is_same_v<Period, std::ratio_multiply<std::ratio<24>, std::chrono::hours::period>>, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/hours.pass.cpp b/libcxx/test/std/utilities/time/hours.pass.cpp
index e04888f2e2a216a489c88e8e6ed04b1266979c70..97fc2621b6acb9ac3d0b31975c705120521f7598 100644
--- a/libcxx/test/std/utilities/time/hours.pass.cpp
+++ b/libcxx/test/std/utilities/time/hours.pass.cpp
@@ -14,7 +14,7 @@
 #include <type_traits>
 #include <limits>
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::hours D;
     typedef D::rep Rep;
@@ -23,4 +23,6 @@ int main()
     static_assert(std::is_integral<Rep>::value, "");
     static_assert(std::numeric_limits<Rep>::digits >= 22, "");
     static_assert((std::is_same<Period, std::ratio<3600> >::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/microseconds.pass.cpp b/libcxx/test/std/utilities/time/microseconds.pass.cpp
index 20e12a9a288b9e744c21ec3c1952e0c6519be3bf..ded1c22fe14f9180c60a7340c6f23fa6aa0adf49 100644
--- a/libcxx/test/std/utilities/time/microseconds.pass.cpp
+++ b/libcxx/test/std/utilities/time/microseconds.pass.cpp
@@ -14,7 +14,7 @@
 #include <type_traits>
 #include <limits>
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::microseconds D;
     typedef D::rep Rep;
@@ -23,4 +23,6 @@ int main()
     static_assert(std::is_integral<Rep>::value, "");
     static_assert(std::numeric_limits<Rep>::digits >= 54, "");
     static_assert((std::is_same<Period, std::micro>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/milliseconds.pass.cpp b/libcxx/test/std/utilities/time/milliseconds.pass.cpp
index 6183b929f198743b3abe282f5a3c54612859e16e..b1fe99e1209f3fd8851d68750288d53a4fce4ee8 100644
--- a/libcxx/test/std/utilities/time/milliseconds.pass.cpp
+++ b/libcxx/test/std/utilities/time/milliseconds.pass.cpp
@@ -14,7 +14,7 @@
 #include <type_traits>
 #include <limits>
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::milliseconds D;
     typedef D::rep Rep;
@@ -23,4 +23,6 @@ int main()
     static_assert(std::is_integral<Rep>::value, "");
     static_assert(std::numeric_limits<Rep>::digits >= 44, "");
     static_assert((std::is_same<Period, std::milli>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/minutes.pass.cpp b/libcxx/test/std/utilities/time/minutes.pass.cpp
index 413d8cd6f697c575b7391299d387882646ad8309..23f0bf2877dee463bd43a5d075df6bb0061531e2 100644
--- a/libcxx/test/std/utilities/time/minutes.pass.cpp
+++ b/libcxx/test/std/utilities/time/minutes.pass.cpp
@@ -14,7 +14,7 @@
 #include <type_traits>
 #include <limits>
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::minutes D;
     typedef D::rep Rep;
@@ -23,4 +23,6 @@ int main()
     static_assert(std::is_integral<Rep>::value, "");
     static_assert(std::numeric_limits<Rep>::digits >= 28, "");
     static_assert((std::is_same<Period, std::ratio<60> >::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/months.pass.cpp b/libcxx/test/std/utilities/time/months.pass.cpp
index ff40823f1ead17722a4dc25a783f91489179cbaf..b14b2fab533ed9992d7efe098c381c3106ba2047 100644
--- a/libcxx/test/std/utilities/time/months.pass.cpp
+++ b/libcxx/test/std/utilities/time/months.pass.cpp
@@ -16,7 +16,7 @@
 #include <type_traits>
 #include <limits>
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::months D;
     typedef D::rep Rep;
@@ -25,4 +25,6 @@ int main()
     static_assert(std::is_integral<Rep>::value, "");
     static_assert(std::numeric_limits<Rep>::digits >= 20, "");
     static_assert(std::is_same_v<Period, std::ratio_divide<std::chrono::years::period, std::ratio<12>>>, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/nanoseconds.pass.cpp b/libcxx/test/std/utilities/time/nanoseconds.pass.cpp
index c14389da728ee825828f2ded66b9dab435a3bccf..d58a375c2a59bdfd2d30da5857a0228bf3424288 100644
--- a/libcxx/test/std/utilities/time/nanoseconds.pass.cpp
+++ b/libcxx/test/std/utilities/time/nanoseconds.pass.cpp
@@ -14,7 +14,7 @@
 #include <type_traits>
 #include <limits>
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::nanoseconds D;
     typedef D::rep Rep;
@@ -23,4 +23,6 @@ int main()
     static_assert(std::is_integral<Rep>::value, "");
     static_assert(std::numeric_limits<Rep>::digits >= 63, "");
     static_assert((std::is_same<Period, std::nano>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/seconds.pass.cpp b/libcxx/test/std/utilities/time/seconds.pass.cpp
index bd2d6d2b3f576f24bbc84a5d22cc089d5b5b6479..45a3f1d8e7fb2ee5818348c98f5fa834a343d95e 100644
--- a/libcxx/test/std/utilities/time/seconds.pass.cpp
+++ b/libcxx/test/std/utilities/time/seconds.pass.cpp
@@ -14,7 +14,7 @@
 #include <type_traits>
 #include <limits>
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::seconds D;
     typedef D::rep Rep;
@@ -23,4 +23,6 @@ int main()
     static_assert(std::is_integral<Rep>::value, "");
     static_assert(std::numeric_limits<Rep>::digits >= 34, "");
     static_assert((std::is_same<Period, std::ratio<1> >::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/time/time.cal/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/time/time.cal/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.members/ctor.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.members/ctor.pass.cpp
index 3a3978cb0828cf1e942faa6da088302916eea24e..5c945fab75ec6ca285b2436db5e0563d9cd85ea2 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.members/ctor.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.members/ctor.pass.cpp
@@ -23,7 +23,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using day = std::chrono::day;
 
@@ -42,4 +42,6 @@ int main()
         day day(i);
         assert(static_cast<unsigned>(day) == i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.members/decrement.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.members/decrement.pass.cpp
index c53af65112e069fe110467149da70a0bba56b6b3..f5323f65956bd20c815f9d35d64143b935c5372f 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.members/decrement.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.members/decrement.pass.cpp
@@ -30,7 +30,7 @@ constexpr bool testConstexpr()
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using day = std::chrono::day;
     ASSERT_NOEXCEPT(--(std::declval<day&>())  );
@@ -48,4 +48,6 @@ int main()
         assert(static_cast<unsigned>(day--) == i - 1);
         assert(static_cast<unsigned>(day)   == i - 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.members/increment.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.members/increment.pass.cpp
index b26d2285aa40192020881a203dd9645cb1f92077..0be8c847f302e0f781931fc429979614105ee5d6 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.members/increment.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.members/increment.pass.cpp
@@ -30,7 +30,7 @@ constexpr bool testConstexpr()
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using day = std::chrono::day;
     ASSERT_NOEXCEPT(++(std::declval<day&>())  );
@@ -48,4 +48,6 @@ int main()
         assert(static_cast<unsigned>(day++) == i + 1);
         assert(static_cast<unsigned>(day)   == i + 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.members/ok.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.members/ok.pass.cpp
index 8a04298ab3cd5a046a895ae3ea2dec28b01c3c63..131df7533c6afd5262f4a03c59c0b80c71a7dcff 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.members/ok.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.members/ok.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using day = std::chrono::day;
     ASSERT_NOEXCEPT(                std::declval<const day>().ok());
@@ -33,4 +33,6 @@ int main()
         assert(day{i}.ok());
     for (unsigned i = 32; i <= 255; ++i)
         assert(!day{i}.ok());
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.members/plus_minus_equal.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.members/plus_minus_equal.pass.cpp
index 42f12af552eab4cef2d45621e3ae1c1e0be6f76b..d182d6c926f0ee73815e8fb2aec9d117a212a253 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.members/plus_minus_equal.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.members/plus_minus_equal.pass.cpp
@@ -32,7 +32,7 @@ constexpr bool testConstexpr()
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using day  = std::chrono::day;
     using days = std::chrono::days;
@@ -53,4 +53,6 @@ int main()
         assert(static_cast<unsigned>(day -= days{12}) == i + 10);
         assert(static_cast<unsigned>(day)             == i + 10);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.nonmembers/comparisons.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.nonmembers/comparisons.pass.cpp
index 6b8a42772726a86f78f01552ea3404f9b1fde784..75bc4cf529af069ddc1a17b28ca633d9a94ea5fb 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.nonmembers/comparisons.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.nonmembers/comparisons.pass.cpp
@@ -23,7 +23,7 @@
 #include "test_macros.h"
 #include "test_comparisons.h"
 
-int main()
+int main(int, char**)
 {
     using day = std::chrono::day;
 
@@ -40,4 +40,6 @@ int main()
     for (unsigned i = 1; i < 10; ++i)
         for (unsigned j = 1; j < 10; ++j)
             assert(testComparisons6Values<day>(i, j));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.nonmembers/literals.fail.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.nonmembers/literals.fail.cpp
index 36352fa35d66b4df1284cb141b0d0e42fc3def57..6331bcf1b23073e664e8257bb9583048d81bf331 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.nonmembers/literals.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.nonmembers/literals.fail.cpp
@@ -20,8 +20,10 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using day = std::chrono::day;
     day d1 = 4d; // expected-error-re {{no matching literal operator for call to 'operator""d' {{.*}}}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.nonmembers/literals.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.nonmembers/literals.pass.cpp
index b3febd4ebe243cb4e00c5bfff6c532e6506e281e..a887736f6e803941b07813a418b8e72652b5d0be 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.nonmembers/literals.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.nonmembers/literals.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     using namespace std::chrono;
@@ -43,4 +43,6 @@ int main()
     assert (d1 == std::chrono::day(4));
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.nonmembers/minus.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.nonmembers/minus.pass.cpp
index 4953d1afe4ef75ce57d2ba6d845e4a9298f4e902..e8ade305adc643a2f83b9b9cb816c998caad70df 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.nonmembers/minus.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.nonmembers/minus.pass.cpp
@@ -33,7 +33,7 @@ constexpr bool testConstexpr()
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using day  = std::chrono::day;
     using days = std::chrono::days;
@@ -54,4 +54,6 @@ int main()
         assert(static_cast<unsigned>(d1) == 12 - i);
         assert(off.count() == static_cast<int>(12 - i)); // days is signed
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.nonmembers/plus.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.nonmembers/plus.pass.cpp
index 10cec0a62d8870ac1ffa53dfebaf0f96d9b7e3c0..e219c7d3c7ae6c21b41cd573ce9144a7b62ba486 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.nonmembers/plus.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.nonmembers/plus.pass.cpp
@@ -33,7 +33,7 @@ constexpr bool testConstexpr()
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using day  = std::chrono::day;
     using days = std::chrono::days;
@@ -55,4 +55,6 @@ int main()
         assert(static_cast<unsigned>(d1) == i + 12);
         assert(static_cast<unsigned>(d2) == i + 12);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.nonmembers/streaming.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.nonmembers/streaming.pass.cpp
index ad3d4f3f9e6c14a0310ca0265900837a404abca2..23ce736c61d879a97d12337f2f3640b2f585896f 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.nonmembers/streaming.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.day/time.cal.day.nonmembers/streaming.pass.cpp
@@ -48,8 +48,10 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
    using day = std::chrono::day;
    std::cout << day{1};
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.day/types.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.day/types.pass.cpp
index d437a6ae3f49d4feba8763e3c9c5e21a99562f24..3c26c57535f304429636e14d4575e27f1afe8727 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.day/types.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.day/types.pass.cpp
@@ -16,10 +16,12 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using day = std::chrono::day;
 
     static_assert(std::is_trivially_copyable_v<day>, "");
     static_assert(std::is_standard_layout_v<day>, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.last/types.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.last/types.pass.cpp
index 10396919bd446df92b55bf833d1bb7f0a85d8cdf..084a6aa8dc59e4e23c680c061eeaf55de45263b9 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.last/types.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.last/types.pass.cpp
@@ -21,7 +21,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using last_spec = std::chrono::last_spec;
 
@@ -29,4 +29,6 @@ int main()
 
     static_assert(std::is_trivially_copyable_v<last_spec>, "");
     static_assert(std::is_standard_layout_v<last_spec>, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.md/time.cal.md.members/ctor.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.md/time.cal.md.members/ctor.pass.cpp
index f3dadd2f6b02a45b2ac58e026e52b3acd520e6b6..48642987a7c1254f90642fb98b800c9a5686e11a 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.md/time.cal.md.members/ctor.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.md/time.cal.md.members/ctor.pass.cpp
@@ -25,7 +25,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using day       = std::chrono::day;
     using month     = std::chrono::month;
@@ -43,4 +43,6 @@ int main()
     static_assert( md1.month() == std::chrono::January, "");
     static_assert( md1.day()   == day{4},               "");
     static_assert( md1.ok(),                            "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.md/time.cal.md.members/day.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.md/time.cal.md.members/day.pass.cpp
index c9c247d508f3eb9e7654b7ad869ac132c763d61c..7137433a9fb63ce056f4456c805682c608500a8b 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.md/time.cal.md.members/day.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.md/time.cal.md.members/day.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using day       = std::chrono::day;
     using month_day = std::chrono::month_day;
@@ -34,4 +34,6 @@ int main()
         month_day md(std::chrono::March, day{i});
         assert( static_cast<unsigned>(md.day()) == i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.md/time.cal.md.members/month.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.md/time.cal.md.members/month.pass.cpp
index e1b46190f0a3ba026ab20729133eb8de2d6d716d..b4744e6d4c731d39872efd02ab8ea3d3df60aaeb 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.md/time.cal.md.members/month.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.md/time.cal.md.members/month.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using day       = std::chrono::day;
     using month     = std::chrono::month;
@@ -35,4 +35,6 @@ int main()
         month_day md(month{i}, day{1});
         assert( static_cast<unsigned>(md.month()) == i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.md/time.cal.md.members/ok.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.md/time.cal.md.members/ok.pass.cpp
index 649f099686718886e7500fdf8e9d613b7d28e853..5e4c0082f5fdbc4cff11a21bb2c9825e5912b949 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.md/time.cal.md.members/ok.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.md/time.cal.md.members/ok.pass.cpp
@@ -21,7 +21,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using day       = std::chrono::day;
     using month     = std::chrono::month;
@@ -51,4 +51,6 @@ int main()
 //  If the month is not ok, all the days are bad
     for (unsigned i = 1; i <= 35; ++i)
         assert(!(month_day{month{13}, day{i}}.ok()));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.md/time.cal.md.nonmembers/comparisons.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.md/time.cal.md.nonmembers/comparisons.pass.cpp
index c186f594c64f9269505759d6303035f025c53068..d7e535a72e7c71e2b0873c6fe0a3aee621b0da14 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.md/time.cal.md.nonmembers/comparisons.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.md/time.cal.md.nonmembers/comparisons.pass.cpp
@@ -26,7 +26,7 @@
 #include "test_macros.h"
 #include "test_comparisons.h"
 
-int main()
+int main(int, char**)
 {
     using day       = std::chrono::day;
     using month     = std::chrono::month;
@@ -66,4 +66,6 @@ int main()
                 month_day{month{2}, day{j}},
                 i == j, i < j )));
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.md/time.cal.md.nonmembers/streaming.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.md/time.cal.md.nonmembers/streaming.pass.cpp
index dbebdfa7d0e8c954d0d4cbc64467e503e57c5770..8eef5f03095623513a922c8b30b2650c9dced5ac 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.md/time.cal.md.nonmembers/streaming.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.md/time.cal.md.nonmembers/streaming.pass.cpp
@@ -31,10 +31,12 @@
 #include <iostream>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using month_day = std::chrono::month_day;
     using month     = std::chrono::month;
     using day       = std::chrono::day;
     std::cout << month_day{month{1}, day{1}};
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.md/types.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.md/types.pass.cpp
index ba7c336a6341a42b90accc0fe0c0ae68e434963f..507855a990fcaca20c19d9566c2bd7fb0d402a86 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.md/types.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.md/types.pass.cpp
@@ -16,10 +16,12 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using month_day = std::chrono::month_day;
 
     static_assert(std::is_trivially_copyable_v<month_day>, "");
     static_assert(std::is_standard_layout_v<month_day>, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.mdlast/comparisons.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.mdlast/comparisons.pass.cpp
index ba9eda73a4ae2bc78ba08eae9eaa2bba4b78cf18..265e7be372dc7f427470aed4b411c9c2ad6c9613 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.mdlast/comparisons.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.mdlast/comparisons.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_macros.h"
 #include "test_comparisons.h"
 
-int main()
+int main(int, char**)
 {
     using month          = std::chrono::month;
     using month_day_last = std::chrono::month_day_last;
@@ -39,4 +39,6 @@ int main()
     for (unsigned i = 1; i < 12; ++i)
         for (unsigned j = 1; j < 12; ++j)
             assert((testComparisons6Values<month_day_last>(month{i}, month{j})));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.mdlast/ctor.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.mdlast/ctor.pass.cpp
index 4bf983f3b4007ffb59f2c8110148d73b4f0c71c8..3696bb907d87c86fd735db75b489fa4d6be914e6 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.mdlast/ctor.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.mdlast/ctor.pass.cpp
@@ -23,7 +23,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using month     = std::chrono::month;
     using month_day_last = std::chrono::month_day_last;
@@ -37,4 +37,6 @@ int main()
     constexpr month_day_last md1{std::chrono::January};
     static_assert( md1.month() == std::chrono::January, "");
     static_assert( md1.ok(),                            "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.mdlast/month.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.mdlast/month.pass.cpp
index b9945b6d88dc241074b03d36d9557887b9954bce..6bf75892da9a01ab06d0fca2c18b22c6395f3490 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.mdlast/month.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.mdlast/month.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using month     = std::chrono::month;
     using month_day_last = std::chrono::month_day_last;
@@ -34,4 +34,6 @@ int main()
         month_day_last mdl(month{i});
         assert( static_cast<unsigned>(mdl.month()) == i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.mdlast/ok.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.mdlast/ok.pass.cpp
index 38c52e22958931808f1660a9d8306230b66529a3..730ab3b25d64a59cf4c64a0a6bfed23c08c7b7a7 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.mdlast/ok.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.mdlast/ok.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using month          = std::chrono::month;
     using month_day_last = std::chrono::month_day_last;
@@ -42,4 +42,6 @@ int main()
         month_day_last mdl{month{i}};
         assert(!mdl.ok());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.mdlast/streaming.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.mdlast/streaming.pass.cpp
index ebb915598545b1a30965df2777058b574a4efa9e..1b4a8f108cb275fd808496e8f88c62ffec323426 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.mdlast/streaming.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.mdlast/streaming.pass.cpp
@@ -25,9 +25,11 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using month_day_last = std::chrono::month_day_last;
     using month          = std::chrono::month;
     std::cout << month_day_last{month{1}};
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.mdlast/types.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.mdlast/types.pass.cpp
index e3f02a8854917ac0923ae4bbcbe9db1ce2fd11ec..c6eebc42de196e239da35624eef56eb2846be01a 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.mdlast/types.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.mdlast/types.pass.cpp
@@ -17,10 +17,12 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using month_day_last = std::chrono::month_day_last;
 
     static_assert(std::is_trivially_copyable_v<month_day_last>, "");
     static_assert(std::is_standard_layout_v<month_day_last>, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.members/ctor.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.members/ctor.pass.cpp
index d0ed4d37d01a766d0480fc74cc027fb43158001d..6800a03e18ad8e6295b649b33bb0e5abe3d64768 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.members/ctor.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.members/ctor.pass.cpp
@@ -23,7 +23,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using month = std::chrono::month;
 
@@ -42,4 +42,6 @@ int main()
         month m(i);
         assert(static_cast<unsigned>(m) == i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.members/decrement.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.members/decrement.pass.cpp
index 2cab328cfcbec1e581db94ddc98447b4aa2ab70c..6d7edc508c13f14d64357116a24f5aaf94c8b3c3 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.members/decrement.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.members/decrement.pass.cpp
@@ -30,7 +30,7 @@ constexpr bool testConstexpr()
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using month = std::chrono::month;
 
@@ -49,4 +49,6 @@ int main()
         assert(static_cast<unsigned>(month--) == i - 1);
         assert(static_cast<unsigned>(month)   == i - 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.members/increment.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.members/increment.pass.cpp
index 81162edf6ca4d6d9b265efff7a0108f992f5e72d..7bcd5bed716182ebb6c6aa85b2b0f215633b8e08 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.members/increment.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.members/increment.pass.cpp
@@ -30,7 +30,7 @@ constexpr bool testConstexpr()
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using month = std::chrono::month;
     ASSERT_NOEXCEPT(++(std::declval<month&>())  );
@@ -48,4 +48,6 @@ int main()
         assert(static_cast<unsigned>(month++) == i + 1);
         assert(static_cast<unsigned>(month)   == i + 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.members/ok.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.members/ok.pass.cpp
index 7cb5edad47f526db6e1378093a7222696a1d93bd..a001c74a3fadc51cd174e408594c184866856438 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.members/ok.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.members/ok.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using month = std::chrono::month;
 
@@ -34,4 +34,6 @@ int main()
         assert(month{i}.ok());
     for (unsigned i = 13; i <= 255; ++i)
         assert(!month{i}.ok());
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.members/plus_minus_equal.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.members/plus_minus_equal.pass.cpp
index 7ca4a6e5f4c3ead9e17708719bb605d7c6aa061b..a792072afa26dba73c641b95499d20189040fa99 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.members/plus_minus_equal.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.members/plus_minus_equal.pass.cpp
@@ -32,7 +32,7 @@ constexpr bool testConstexpr()
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using month  = std::chrono::month;
     using months = std::chrono::months;
@@ -63,4 +63,6 @@ int main()
         assert(static_cast<unsigned>(month -= months{ 9}) == static_cast<unsigned>(exp));
         assert(static_cast<unsigned>(month)               == static_cast<unsigned>(exp));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.nonmembers/comparisons.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.nonmembers/comparisons.pass.cpp
index aa37fde3b29c6cb71d326ad35da9749d784bd162..f69fec8aaac7d57b66ee75940d4bbd32b17d020a 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.nonmembers/comparisons.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.nonmembers/comparisons.pass.cpp
@@ -26,7 +26,7 @@
 #include "test_comparisons.h"
 
 
-int main()
+int main(int, char**)
 {
     using month = std::chrono::month;
 
@@ -43,4 +43,6 @@ int main()
     for (unsigned i = 1; i < 10; ++i)
         for (unsigned j = 10; j < 10; ++j)
             assert(testComparisons6Values<month>(i, j));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.nonmembers/literals.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.nonmembers/literals.pass.cpp
index 807cf29881b820d5b45dba3319bfa1aae5abdd15..9832fe37681cd10fbb8985807bb6d210478f19b6 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.nonmembers/literals.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.nonmembers/literals.pass.cpp
@@ -29,7 +29,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 
     ASSERT_SAME_TYPE(const std::chrono::month, decltype(std::chrono::January));
@@ -83,4 +83,6 @@ int main()
     assert(static_cast<unsigned>(std::chrono::October)   == 10);
     assert(static_cast<unsigned>(std::chrono::November)  == 11);
     assert(static_cast<unsigned>(std::chrono::December)  == 12);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.nonmembers/minus.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.nonmembers/minus.pass.cpp
index 291d299e3af68fd9ead70d11a22691fdf40da106..cda36412741dca7dadf7178a62da45a4e6d6d1b5 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.nonmembers/minus.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.nonmembers/minus.pass.cpp
@@ -44,7 +44,7 @@ constexpr bool testConstexpr()
 
 #include <iostream>
 
-int main()
+int main(int, char**)
 {
     using month  = std::chrono::month;
     using months = std::chrono::months;
@@ -68,4 +68,6 @@ static_assert(testConstexpr<month, months>(), "");
         assert(static_cast<unsigned>(m1) == static_cast<unsigned>(exp));
 //          assert(off.count()               == static_cast<unsigned>(exp));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.nonmembers/plus.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.nonmembers/plus.pass.cpp
index 87b39003b1e55dc2f3a9df96a9e7d14a383f8d36..58a951e1b0e7680c5a08f1998c79dc0892fd9e62 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.nonmembers/plus.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.nonmembers/plus.pass.cpp
@@ -43,7 +43,7 @@ constexpr bool testConstexpr()
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using month  = std::chrono::month;
     using months = std::chrono::months;
@@ -68,4 +68,6 @@ int main()
         assert(static_cast<unsigned>(m1) == exp);
         assert(static_cast<unsigned>(m2) == exp);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.nonmembers/streaming.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.nonmembers/streaming.pass.cpp
index 5f3f3884f6b39e45d45683593583502d2a68cae4..1d3aa7ce4e889e4202efb32d4945444074a2e53a 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.nonmembers/streaming.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.month/time.cal.month.nonmembers/streaming.pass.cpp
@@ -45,8 +45,10 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
    using month = std::chrono::month;
    std::cout << month{1};
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.month/types.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.month/types.pass.cpp
index b3e5024656ffa261fb6c2ce6a8431e220fff4a35..a6e67f1013451c1e88b020c12b51bcf14f9cf9fe 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.month/types.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.month/types.pass.cpp
@@ -16,10 +16,12 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using month = std::chrono::month;
 
     static_assert(std::is_trivially_copyable_v<month>, "");
     static_assert(std::is_standard_layout_v<month>, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.mwd/time.cal.mwd.members/ctor.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.mwd/time.cal.mwd.members/ctor.pass.cpp
index 8d0b560b1fd0137e6fd8a062dca56855f8fb9251..8804e71e3e8e4ee4a4a3083d215c1c4e7b10b86f 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.mwd/time.cal.mwd.members/ctor.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.mwd/time.cal.mwd.members/ctor.pass.cpp
@@ -24,7 +24,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using month_weekday   = std::chrono::month_weekday;
     using month           = std::chrono::month;
@@ -42,4 +42,6 @@ int main()
     static_assert( md1.month() == std::chrono::January,                              "");
     static_assert( md1.weekday_indexed() == weekday_indexed{std::chrono::Friday, 4}, "");
     static_assert( md1.ok(),                                                         "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.mwd/time.cal.mwd.members/month.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.mwd/time.cal.mwd.members/month.pass.cpp
index 99bdcb1607cfacc626dc8f17fbaa40e62845a799..35e7c83c7928acf05d88d1fc967731bd0b84d89d 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.mwd/time.cal.mwd.members/month.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.mwd/time.cal.mwd.members/month.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using month_weekday   = std::chrono::month_weekday;
     using month           = std::chrono::month;
@@ -38,4 +38,6 @@ int main()
         month_weekday md(month{i}, weekday_indexed{Sunday, 1});
         assert( static_cast<unsigned>(md.month()) == i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.mwd/time.cal.mwd.members/ok.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.mwd/time.cal.mwd.members/ok.pass.cpp
index b4999652fd5736e277c225e0d2db4bc3c4a9345a..2ff1bf735f2f1e069730f47af4a3bc3818fca490 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.mwd/time.cal.mwd.members/ok.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.mwd/time.cal.mwd.members/ok.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using month_weekday   = std::chrono::month_weekday;
     using month           = std::chrono::month;
@@ -47,4 +47,6 @@ int main()
 //  If the month is not ok, all the weekday_indexed are bad
     for (unsigned i = 1; i <= 10; ++i)
         assert(!(month_weekday{month{13}, weekday_indexed{Sunday, i}}.ok()));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.mwd/time.cal.mwd.members/weekday_indexed.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.mwd/time.cal.mwd.members/weekday_indexed.pass.cpp
index d80ae29d0480e744c080f8fa911db04597f1bdcf..13a1bba53ddda7c4155b2f419d1ab09edb48c560 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.mwd/time.cal.mwd.members/weekday_indexed.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.mwd/time.cal.mwd.members/weekday_indexed.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using month_weekday   = std::chrono::month_weekday;
     using month           = std::chrono::month;
@@ -39,4 +39,6 @@ int main()
         assert( static_cast<unsigned>(md.weekday_indexed().weekday() == Sunday));
         assert( static_cast<unsigned>(md.weekday_indexed().index() == i));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.mwd/time.cal.mwd.nonmembers/comparisons.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.mwd/time.cal.mwd.nonmembers/comparisons.pass.cpp
index 64df8840e74048e4bb4698f4acd434206ef59ffd..46f756de06c1a3148896112ed003bee65516a481 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.mwd/time.cal.mwd.nonmembers/comparisons.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.mwd/time.cal.mwd.nonmembers/comparisons.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_macros.h"
 #include "test_comparisons.h"
 
-int main()
+int main(int, char**)
 {
     using month_weekday   = std::chrono::month_weekday;
     using month           = std::chrono::month;
@@ -82,4 +82,6 @@ int main()
                 month_weekday{month{2}, weekday_indexed{weekday{i}, 2}},
                 month_weekday{month{2}, weekday_indexed{weekday{j}, 2}},
                 i == j)));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.mwd/time.cal.mwd.nonmembers/streaming.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.mwd/time.cal.mwd.nonmembers/streaming.pass.cpp
index e7981b5713a124d8991a8f29e4e1852315f25577..11a1d4ecd0444aee3f7dedad44b8a1a361389490 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.mwd/time.cal.mwd.nonmembers/streaming.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.mwd/time.cal.mwd.nonmembers/streaming.pass.cpp
@@ -24,7 +24,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using month_weekday   = std::chrono::month_weekday;
     using month           = std::chrono::month;
@@ -32,4 +32,6 @@ int main()
     using weekday         = std::chrono::weekday;
 
     std::cout << month_weekday{month{1}, weekday_indexed{weekday{3}, 3}};
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.mwd/types.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.mwd/types.pass.cpp
index 67c3f17b94652be21cc6fd653a787b55f1afc160..bd4f4e1d492f80c2ba3fa6e0dc770c3ef14df791 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.mwd/types.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.mwd/types.pass.cpp
@@ -16,10 +16,12 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using month_weekday = std::chrono::month_weekday;
 
     static_assert(std::is_trivially_copyable_v<month_weekday>, "");
     static_assert(std::is_standard_layout_v<month_weekday>, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.mwdlast/time.cal.mwdlast.members/ctor.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.mwdlast/time.cal.mwdlast.members/ctor.pass.cpp
index fa5ca0443580cd5fac5cde1a0f053b6851841549..d83bbe92f11b4b12c142176d4d2e5013f374100f 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.mwdlast/time.cal.mwdlast.members/ctor.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.mwdlast/time.cal.mwdlast.members/ctor.pass.cpp
@@ -27,7 +27,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using month              = std::chrono::month;
     using weekday            = std::chrono::weekday;
@@ -56,4 +56,6 @@ int main()
     static_assert( mwdl3.month() == January,                         "");
     static_assert( mwdl3.weekday_last() == weekday_last{weekday{4}}, "");
     static_assert( mwdl3.ok(),                                       "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.mwdlast/time.cal.mwdlast.members/month.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.mwdlast/time.cal.mwdlast.members/month.pass.cpp
index 3561651c28adc3784ff960e236cb5f93f42566c4..a32b0899615270c5bae9d7b797443fbccf4847b8 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.mwdlast/time.cal.mwdlast.members/month.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.mwdlast/time.cal.mwdlast.members/month.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using month              = std::chrono::month;
     using weekday            = std::chrono::weekday;
@@ -38,4 +38,6 @@ int main()
         month_weekday_last mdl(month{i}, weekday_last{Tuesday});
         assert( static_cast<unsigned>(mdl.month()) == i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.mwdlast/time.cal.mwdlast.members/ok.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.mwdlast/time.cal.mwdlast.members/ok.pass.cpp
index 10245f938d68c6c29b966a0fce48f1c542a62a85..02df5fbd22bd08b67c40503fe2da3e91cec596bb 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.mwdlast/time.cal.mwdlast.members/ok.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.mwdlast/time.cal.mwdlast.members/ok.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using month              = std::chrono::month;
     using weekday            = std::chrono::weekday;
@@ -48,4 +48,6 @@ int main()
         month_weekday_last mwdl{January, weekday_last{weekday{i}}};
         assert( mwdl.ok() == weekday_last{weekday{i}}.ok());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.mwdlast/time.cal.mwdlast.members/weekday_last.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.mwdlast/time.cal.mwdlast.members/weekday_last.pass.cpp
index 4afa6cca73475e8f15937bd266d9d2fab0d48779..4ecf6d24628df7b92e89d1b0ee0bddd19f51a54a 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.mwdlast/time.cal.mwdlast.members/weekday_last.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.mwdlast/time.cal.mwdlast.members/weekday_last.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using month              = std::chrono::month;
     using weekday            = std::chrono::weekday;
@@ -40,4 +40,6 @@ int main()
         month_weekday_last mdl(January, weekday_last{weekday{i}});
         assert( static_cast<unsigned>(mdl.weekday_last().weekday()) == i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.mwdlast/time.cal.mwdlast.nonmembers/comparisons.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.mwdlast/time.cal.mwdlast.nonmembers/comparisons.pass.cpp
index 4d0e935f11a0231466c1d10ed832f1f4bf03f61b..911693c25bf4734a10ced6ec394825c370d644f8 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.mwdlast/time.cal.mwdlast.nonmembers/comparisons.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.mwdlast/time.cal.mwdlast.nonmembers/comparisons.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_macros.h"
 #include "test_comparisons.h"
 
-int main()
+int main(int, char**)
 {
     using month              = std::chrono::month;
     using weekday_last       = std::chrono::weekday_last;
@@ -69,4 +69,6 @@ int main()
             month_weekday_last{month{1}, weekday_last{weekday{1}}},
             month_weekday_last{month{2}, weekday_last{weekday{2}}},
         false)));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.mwdlast/time.cal.mwdlast.nonmembers/streaming.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.mwdlast/time.cal.mwdlast.nonmembers/streaming.pass.cpp
index 2bf0e1ec43b75f8db729ac52602951adc29fd55f..75654b1b3a2d23926645c1b342e95942135119ee 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.mwdlast/time.cal.mwdlast.nonmembers/streaming.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.mwdlast/time.cal.mwdlast.nonmembers/streaming.pass.cpp
@@ -25,7 +25,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using month_weekday_last = std::chrono::month_weekday_last;
     using month              = std::chrono::month;
@@ -33,4 +33,6 @@ int main()
     using weekday_last       = std::chrono::weekday_last;
 
     std::cout << month_weekday_last{month{1}, weekday_last{weekday{3}}};
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.mwdlast/types.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.mwdlast/types.pass.cpp
index 2271f42c0313cc440ce3d533bf4743dfdfefbf96..2f2676d7a5242d1123350a1d9ab72e389581fd7d 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.mwdlast/types.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.mwdlast/types.pass.cpp
@@ -17,10 +17,12 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using month_weekday_last = std::chrono::month_weekday_last;
 
     static_assert(std::is_trivially_copyable_v<month_weekday_last>, "");
     static_assert(std::is_standard_layout_v<month_weekday_last>, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.operators/month_day.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.operators/month_day.pass.cpp
index e51fb4fa47eb3f33efeef02606e2b69335ee12e0..e9eb80bfd98f7b57efd597583b3bb6e137c46828 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.operators/month_day.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.operators/month_day.pass.cpp
@@ -38,7 +38,7 @@
 #include "test_macros.h"
 #include "test_comparisons.h"
 
-int main()
+int main(int, char**)
 {
     using month_day = std::chrono::month_day;
     using month     = std::chrono::month;
@@ -104,4 +104,6 @@ int main()
                 assert(md1 == md2);
             }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.operators/month_day_last.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.operators/month_day_last.pass.cpp
index 27043b88c639a4ffded5cc1e186a7a18b18cf38d..84c2c6eaa3919b8c23d08b771bee174d82d1581d 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.operators/month_day_last.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.operators/month_day_last.pass.cpp
@@ -46,7 +46,7 @@
 #include "test_macros.h"
 #include "test_comparisons.h"
 
-int main()
+int main(int, char**)
 {
     using month          = std::chrono::month;
     using month_day_last = std::chrono::month_day_last;
@@ -103,4 +103,6 @@ int main()
         }
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.operators/month_weekday.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.operators/month_weekday.pass.cpp
index 4dc6db768e283e64adf8f2106fffe27d9230c4eb..60b788de1e45743ce8f3a6f17d965ff820a1fa33 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.operators/month_weekday.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.operators/month_weekday.pass.cpp
@@ -44,7 +44,7 @@
 #include "test_macros.h"
 #include "test_comparisons.h"
 
-int main()
+int main(int, char**)
 {
     using month_weekday   = std::chrono::month_weekday;
     using month           = std::chrono::month;
@@ -111,4 +111,6 @@ int main()
                     assert(mwd1 == mwd2);
                 }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.operators/month_weekday_last.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.operators/month_weekday_last.pass.cpp
index 25d25b26d9b59f679c7c9bfb3f727a808266bf7c..07e5d8d75d620e01aa3eb9133d6e9249ac266d70 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.operators/month_weekday_last.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.operators/month_weekday_last.pass.cpp
@@ -36,7 +36,7 @@
 #include "test_macros.h"
 #include "test_comparisons.h"
 
-int main()
+int main(int, char**)
 {
     using month_weekday      = std::chrono::month_weekday;
     using month              = std::chrono::month;
@@ -103,4 +103,6 @@ int main()
                 assert(mwd1 == mwd2);
             }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.operators/year_month.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.operators/year_month.pass.cpp
index 6ef320ebb79cca13521aa496f16530b28051f3c8..ba2b5c187f6fad2d7ac3319aef039c7bc7165f74 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.operators/year_month.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.operators/year_month.pass.cpp
@@ -25,7 +25,7 @@
 #include "test_macros.h"
 #include "test_comparisons.h"
 
-int main()
+int main(int, char**)
 {
     using month      = std::chrono::month;
     using year       = std::chrono::year;
@@ -64,4 +64,6 @@ int main()
                 assert(static_cast<unsigned>(ym.month()) == j);
             }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.operators/year_month_day.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.operators/year_month_day.pass.cpp
index a8df70096325d0d621b6ae16c7c2f45f550a5961..a5aa4d0ef59ddbd3163f13202b3039d19b3ad6f3 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.operators/year_month_day.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.operators/year_month_day.pass.cpp
@@ -42,7 +42,7 @@
 #include "test_macros.h"
 #include "test_comparisons.h"
 
-int main()
+int main(int, char**)
 {
     using year           = std::chrono::year;
     using month          = std::chrono::month;
@@ -187,4 +187,6 @@ int main()
                 }
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.operators/year_month_day_last.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.operators/year_month_day_last.pass.cpp
index 2556bb93f3675882d953b159812ff7d9ed55d2a2..fd55e38b4c4eebc80c5b45f3e222067fc58ee968 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.operators/year_month_day_last.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.operators/year_month_day_last.pass.cpp
@@ -38,7 +38,7 @@
 #include "test_macros.h"
 #include "test_comparisons.h"
 
-int main()
+int main(int, char**)
 {
     using month               = std::chrono::month;
     using year_month          = std::chrono::year_month;
@@ -121,4 +121,6 @@ int main()
                 assert(ymdl1 == ymdl2);
             }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.operators/year_month_weekday.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.operators/year_month_weekday.pass.cpp
index af27c945e09755b69e2dc24dc9d2d2fa62527813..4e71435805aa4f6263308c9a2e1201051b75eca5 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.operators/year_month_weekday.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.operators/year_month_weekday.pass.cpp
@@ -37,7 +37,7 @@
 #include "test_macros.h"
 #include "test_comparisons.h"
 
-int main()
+int main(int, char**)
 {
     using year               = std::chrono::year;
     using year_month         = std::chrono::year_month;
@@ -141,4 +141,6 @@ int main()
                         assert(ymd1 == ymd2);
                     }
      }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.operators/year_month_weekday_last.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.operators/year_month_weekday_last.pass.cpp
index ff467aa60c3ecebf483039a5e44d5e9e7927209a..62b1f46765cdf7012eb7d5fff58ffb30acd38ed6 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.operators/year_month_weekday_last.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.operators/year_month_weekday_last.pass.cpp
@@ -39,7 +39,7 @@
 #include "test_macros.h"
 #include "test_comparisons.h"
 
-int main()
+int main(int, char**)
 {
     using year_month         = std::chrono::year_month;
     using year               = std::chrono::year;
@@ -149,4 +149,6 @@ int main()
                     assert(ymwdl1 == ymwdl2);
                 }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.wdidx/time.cal.wdidx.members/ctor.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.wdidx/time.cal.wdidx.members/ctor.pass.cpp
index b9facef63e736325d0b06115018e21c387b8ac90..4a64b932b686a72eacbef61204467a960af44060 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.wdidx/time.cal.wdidx.members/ctor.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.wdidx/time.cal.wdidx.members/ctor.pass.cpp
@@ -26,7 +26,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using weekday  = std::chrono::weekday;
     using weekday_indexed = std::chrono::weekday_indexed;
@@ -57,4 +57,6 @@ int main()
         weekday_indexed wdi(std::chrono::Tuesday, i);
         assert(!wdi.ok());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.wdidx/time.cal.wdidx.members/index.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.wdidx/time.cal.wdidx.members/index.pass.cpp
index 043a98accf55fb2fbc846baac95507fc00ea0119..4942f7164807e69f165d22888778d245223d2e24 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.wdidx/time.cal.wdidx.members/index.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.wdidx/time.cal.wdidx.members/index.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using weekday         = std::chrono::weekday;
     using weekday_indexed = std::chrono::weekday_indexed;
@@ -34,4 +34,6 @@ int main()
         weekday_indexed wdi(weekday{2}, i);
         assert( static_cast<unsigned>(wdi.index()) == i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.wdidx/time.cal.wdidx.members/ok.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.wdidx/time.cal.wdidx.members/ok.pass.cpp
index 1cdfb29c96ead588dc5d430cd4d3c61036df167a..a2b5b48e4fc6414825df4fdfa9693c64cb00d9bd 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.wdidx/time.cal.wdidx.members/ok.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.wdidx/time.cal.wdidx.members/ok.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using weekday         = std::chrono::weekday;
     using weekday_indexed = std::chrono::weekday_indexed;
@@ -45,4 +45,6 @@ int main()
 
 //  Not a valid weekday
     assert(!(weekday_indexed(weekday{9U}, 1).ok()));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.wdidx/time.cal.wdidx.members/weekday.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.wdidx/time.cal.wdidx.members/weekday.pass.cpp
index 47f50b6d672b7d20c9623167451fc2603d1ddc0c..e9c204d08b152c03d03bea346fbd648b16ad7786 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.wdidx/time.cal.wdidx.members/weekday.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.wdidx/time.cal.wdidx.members/weekday.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using weekday         = std::chrono::weekday;
     using weekday_indexed = std::chrono::weekday_indexed;
@@ -35,4 +35,6 @@ int main()
         weekday_indexed wdi(weekday{i}, 2);
         assert( static_cast<unsigned>(wdi.weekday()) == i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.wdidx/time.cal.wdidx.nonmembers/comparisons.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.wdidx/time.cal.wdidx.nonmembers/comparisons.pass.cpp
index 963f9f15ec8532d60415f652c78922c8c0ba8beb..104c59abf782638c1f02f8019acb7494e0060919 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.wdidx/time.cal.wdidx.nonmembers/comparisons.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.wdidx/time.cal.wdidx.nonmembers/comparisons.pass.cpp
@@ -22,7 +22,7 @@
 #include "test_macros.h"
 #include "test_comparisons.h"
 
-int main()
+int main(int, char**)
 {
     using weekday         = std::chrono::weekday;
     using weekday_indexed = std::chrono::weekday_indexed;
@@ -44,4 +44,6 @@ int main()
     static_assert( (weekday_indexed{weekday{1}, 2} != weekday_indexed{weekday{1}, 1}), "");
     static_assert(!(weekday_indexed{weekday{1}, 2} == weekday_indexed{weekday{2}, 2}),  "");
     static_assert( (weekday_indexed{weekday{1}, 2} != weekday_indexed{weekday{2}, 2}),  "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.wdidx/time.cal.wdidx.nonmembers/streaming.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.wdidx/time.cal.wdidx.nonmembers/streaming.pass.cpp
index 810b2cb0c499ad653a121688b4e9d95692ec9ad5..5052a182458129b6f1a30bf7731b79f4f3d8bc13 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.wdidx/time.cal.wdidx.nonmembers/streaming.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.wdidx/time.cal.wdidx.nonmembers/streaming.pass.cpp
@@ -26,10 +26,12 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using weekday_indexed = std::chrono::weekday_indexed;
     using weekday         = std::chrono::weekday;
 
     std::cout << weekday_indexed{weekday{3}};
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.wdidx/types.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.wdidx/types.pass.cpp
index 74634da8a5897625e074b805b4adaf63a477cbca..260b50f465dfc603bdb6e7cd04b60aa88242c3e0 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.wdidx/types.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.wdidx/types.pass.cpp
@@ -16,10 +16,12 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using weekday_indexed = std::chrono::weekday_indexed;
 
     static_assert(std::is_trivially_copyable_v<weekday_indexed>, "");
     static_assert(std::is_standard_layout_v<weekday_indexed>, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.wdlast/time.cal.wdlast.members/ctor.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.wdlast/time.cal.wdlast.members/ctor.pass.cpp
index f7fa66320412b27f7b3398dfd86e282a2ec445f3..a569144d068225a1a470f7557c9ebc19e045e5c1 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.wdlast/time.cal.wdlast.members/ctor.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.wdlast/time.cal.wdlast.members/ctor.pass.cpp
@@ -23,7 +23,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using weekday      = std::chrono::weekday;
     using weekday_last = std::chrono::weekday_last;
@@ -43,4 +43,6 @@ int main()
         weekday_last wdl{weekday{i}};
         assert(wdl.weekday() == weekday{i});
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.wdlast/time.cal.wdlast.members/ok.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.wdlast/time.cal.wdlast.members/ok.pass.cpp
index d708a8124634c3fa30d45ed3393becfa48cff314..eb0636aa9cf307d91b6b06e74bd0eb3047a48dd7 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.wdlast/time.cal.wdlast.members/ok.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.wdlast/time.cal.wdlast.members/ok.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using weekday      = std::chrono::weekday;
     using weekday_last = std::chrono::weekday_last;
@@ -33,4 +33,6 @@ int main()
 
     for (unsigned i = 0; i <= 255; ++i)
         assert(weekday_last{weekday{i}}.ok() == weekday{i}.ok());
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.wdlast/time.cal.wdlast.members/weekday.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.wdlast/time.cal.wdlast.members/weekday.pass.cpp
index 48767b3b86e9df41454e7b2ff5d23eb1866055ec..c5eb6e13201516f3c38966dcfff8da6db081c52c 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.wdlast/time.cal.wdlast.members/weekday.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.wdlast/time.cal.wdlast.members/weekday.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using weekday      = std::chrono::weekday;
     using weekday_last = std::chrono::weekday_last;
@@ -29,4 +29,6 @@ int main()
 
     for (unsigned i = 0; i <= 255; ++i)
         assert(weekday_last{weekday{i}}.weekday() == weekday{i});
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.wdlast/time.cal.wdlast.nonmembers/comparisons.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.wdlast/time.cal.wdlast.nonmembers/comparisons.pass.cpp
index 1a9fc97eb51710213b37668c3cd0d6421120221b..c5ca36e828804f6abe03d5e0a105c9d0fb9ac2d2 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.wdlast/time.cal.wdlast.nonmembers/comparisons.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.wdlast/time.cal.wdlast.nonmembers/comparisons.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_macros.h"
 #include "test_comparisons.h"
 
-int main()
+int main(int, char**)
 {
     using weekday      = std::chrono::weekday;
     using weekday_last = std::chrono::weekday_last;
@@ -39,4 +39,6 @@ int main()
     for (unsigned i = 0; i < 6; ++i)
         for (unsigned j = 0; j < 6; ++j)
             assert(testComparisons2Values<weekday_last>(weekday{i}, weekday{j}));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.wdlast/time.cal.wdlast.nonmembers/streaming.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.wdlast/time.cal.wdlast.nonmembers/streaming.pass.cpp
index efb598472552b72f35a418603c612466435a546b..85a40a3dc4cb4a7ee314586bc5a91a8fda61b37a 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.wdlast/time.cal.wdlast.nonmembers/streaming.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.wdlast/time.cal.wdlast.nonmembers/streaming.pass.cpp
@@ -24,10 +24,12 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
    using weekday_last = std::chrono::weekday_last;
    using weekday      = std::chrono::weekday;
 
    std::cout << weekday_last{weekday{3}};
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.wdlast/types.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.wdlast/types.pass.cpp
index c986f99c3324d9b2d1b5575eb37ea238689ebb21..ff9d54f88daad63e2f734f05af214ce54cced20d 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.wdlast/types.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.wdlast/types.pass.cpp
@@ -16,10 +16,12 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using weekday_last = std::chrono::weekday_last;
 
     static_assert(std::is_trivially_copyable_v<weekday_last>, "");
     static_assert(std::is_standard_layout_v<weekday_last>, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/ctor.local_days.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/ctor.local_days.pass.cpp
index ee241c8e7c9f8bb0eeb2426bf170f0a61ed21afe..06656fb442a37790d6412c851a471abbc65d608e 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/ctor.local_days.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/ctor.local_days.pass.cpp
@@ -29,7 +29,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using local_days = std::chrono::local_days;
     using days       = std::chrono::days;
@@ -69,4 +69,6 @@ int main()
     assert( wd.ok());
     assert(static_cast<unsigned>(wd) == 3);
     }
+
+    return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/ctor.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/ctor.pass.cpp
index 9ec3afb2144fbd4d410d1ab3e546a0eb9bd6403e..470b9d79d237c17feaacacb8acd27017a0162655 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/ctor.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/ctor.pass.cpp
@@ -26,7 +26,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using weekday = std::chrono::weekday;
 
@@ -47,4 +47,6 @@ int main()
     }
 
 // TODO - sys_days and local_days ctor tests
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/ctor.sys_days.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/ctor.sys_days.pass.cpp
index 920b53e783cfd961bf7cf7022637b7b7bd2069d0..e00184a99150a6d370bd95b39c4470492b8149eb 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/ctor.sys_days.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/ctor.sys_days.pass.cpp
@@ -29,7 +29,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using sys_days  = std::chrono::sys_days;
     using days      = std::chrono::days;
@@ -69,4 +69,6 @@ int main()
     assert( wd.ok());
     assert(static_cast<unsigned>(wd) == 3);
     }
+
+    return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/decrement.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/decrement.pass.cpp
index c8b023a37c515e05f85eaec5d446e6426dedf9ad..d574e1db9b604a80fe2df2ed10b8ed6420e0c0c1 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/decrement.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/decrement.pass.cpp
@@ -31,7 +31,7 @@ constexpr bool testConstexpr()
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using weekday = std::chrono::weekday;
     ASSERT_NOEXCEPT(--(std::declval<weekday&>())  );
@@ -49,4 +49,6 @@ int main()
         assert((static_cast<unsigned>(wd--) == euclidian_subtraction<unsigned, 0, 6>(i, 1)));
         assert((static_cast<unsigned>(wd)   == euclidian_subtraction<unsigned, 0, 6>(i, 2)));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/increment.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/increment.pass.cpp
index d9239ff8f906e6678ed07c032edd8a408bdfd2af..bb62e0120ef02ede97013ce9aa7889fb208c27b1 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/increment.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/increment.pass.cpp
@@ -31,7 +31,7 @@ constexpr bool testConstexpr()
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using weekday = std::chrono::weekday;
     ASSERT_NOEXCEPT(++(std::declval<weekday&>())  );
@@ -49,4 +49,6 @@ int main()
         assert((static_cast<unsigned>(wd++) == euclidian_addition<unsigned, 0, 6>(i, 1)));
         assert((static_cast<unsigned>(wd)   == euclidian_addition<unsigned, 0, 6>(i, 2)));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/ok.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/ok.pass.cpp
index f8bd9d43a25ff7b13b2bf0d41a253f81f02a18f2..f2f6e2e980299d56759f3bbe479e2d92b2a84975 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/ok.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/ok.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using weekday = std::chrono::weekday;
 
@@ -34,4 +34,6 @@ int main()
         assert(weekday{i}.ok());
     for (unsigned i = 7; i <= 255; ++i)
         assert(!weekday{i}.ok());
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/operator[].pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/operator[].pass.cpp
index aa0f3f7e59e51ad5263336d9d500970597d14d8e..d7d2d6faf30ccab57fad989dc2b00249bf7ecbfb 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/operator[].pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/operator[].pass.cpp
@@ -21,7 +21,7 @@
 #include "test_macros.h"
 #include "../../euclidian.h"
 
-int main()
+int main(int, char**)
 {
     using weekday         = std::chrono::weekday;
     using weekday_last    = std::chrono::weekday_last;
@@ -55,4 +55,6 @@ int main()
         assert(wdi.index() == j);
         assert(wdi.ok());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/plus_minus_equal.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/plus_minus_equal.pass.cpp
index e0963540cf2fc059e10565aef14e50003ec6f1a9..d99b0349399d0b419ee13297c905c8a3734761a7 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/plus_minus_equal.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.members/plus_minus_equal.pass.cpp
@@ -33,7 +33,7 @@ constexpr bool testConstexpr()
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using weekday = std::chrono::weekday;
     using days    = std::chrono::days;
@@ -59,4 +59,6 @@ int main()
         assert((static_cast<unsigned>(wd -= days{4}) == euclidian_subtraction<unsigned, 0, 6>(i, 4)));
         assert((static_cast<unsigned>(wd)            == euclidian_subtraction<unsigned, 0, 6>(i, 4)));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.nonmembers/comparisons.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.nonmembers/comparisons.pass.cpp
index c042ac14778a28538d828111a1146c909784337e..982b3bccbc698e625435271c79d202cd27f7bc42 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.nonmembers/comparisons.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.nonmembers/comparisons.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_macros.h"
 #include "test_comparisons.h"
 
-int main()
+int main(int, char**)
 {
     using weekday = std::chrono::weekday;
 
@@ -38,4 +38,6 @@ int main()
     for (unsigned i = 0; i < 6; ++i)
         for (unsigned j = 0; j < 6; ++j)
             assert(testComparisons2Values<weekday>(i, j));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.nonmembers/literals.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.nonmembers/literals.pass.cpp
index 8f713aad2808d85778a5deaa71413a75f49f76f2..7529864a5bb37a54b6f11d8c9566cc8173f8068e 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.nonmembers/literals.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.nonmembers/literals.pass.cpp
@@ -24,7 +24,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 
     ASSERT_SAME_TYPE(const std::chrono::weekday, decltype(std::chrono::Sunday));
@@ -58,4 +58,6 @@ int main()
     assert(static_cast<unsigned>(std::chrono::Thursday)  ==  4);
     assert(static_cast<unsigned>(std::chrono::Friday)    ==  5);
     assert(static_cast<unsigned>(std::chrono::Saturday)  ==  6);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.nonmembers/minus.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.nonmembers/minus.pass.cpp
index 2bf0ed7899530972ff43733f0f20d3e6f6c1d9c9..f296fc6d68eb1fdfc7ad98ccfe77534b806e42ff 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.nonmembers/minus.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.nonmembers/minus.pass.cpp
@@ -44,7 +44,7 @@ constexpr bool testConstexpr()
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using weekday  = std::chrono::weekday;
     using days     = std::chrono::days;
@@ -72,4 +72,6 @@ int main()
             assert(weekday{i} + d == weekday{j});
         }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.nonmembers/plus.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.nonmembers/plus.pass.cpp
index 287834cd7e86689dda96ef742b738edaddacdfbf..78d332b96cbe20720b84b3e82e3e304756261de2 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.nonmembers/plus.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.nonmembers/plus.pass.cpp
@@ -44,7 +44,7 @@ constexpr bool testConstexpr()
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using weekday = std::chrono::weekday;
     using days    = std::chrono::days;
@@ -66,4 +66,6 @@ int main()
             assert((static_cast<unsigned>(wd1) == euclidian_addition<unsigned, 0, 6>(i, j)));
             assert((static_cast<unsigned>(wd2) == euclidian_addition<unsigned, 0, 6>(i, j)));
         }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.nonmembers/streaming.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.nonmembers/streaming.pass.cpp
index aef5a82e78d2149667d89b8ec10e5167ec983303..43825b60e99feebf062e8dd19dc5475bd1b0ac09 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.nonmembers/streaming.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.nonmembers/streaming.pass.cpp
@@ -47,9 +47,11 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
    using weekday = std::chrono::weekday;
 
    std::cout << weekday{3};
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/types.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/types.pass.cpp
index ed355b025155403e6d8d50ab52b526e6a9520287..7264a210f59f4db205f34d25bd5ea9501194d0fc 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/types.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.weekday/types.pass.cpp
@@ -16,10 +16,12 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using weekday = std::chrono::weekday;
 
     static_assert(std::is_trivially_copyable_v<weekday>, "");
     static_assert(std::is_standard_layout_v<weekday>, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.members/ctor.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.members/ctor.pass.cpp
index 5f8b4660a241e3683c4c95af83fdd91fd074f6aa..e46b556306430475b90a41dfc512bdd7b58e163e 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.members/ctor.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.members/ctor.pass.cpp
@@ -23,7 +23,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year = std::chrono::year;
 
@@ -42,4 +42,6 @@ int main()
         year year(i);
         assert(static_cast<int>(year) == i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.members/decrement.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.members/decrement.pass.cpp
index e8473bf981092d422f3e46b703e4259e998db10b..893c48aab476a2efcd484eeb5c9ee82ba5969e1e 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.members/decrement.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.members/decrement.pass.cpp
@@ -30,7 +30,7 @@ constexpr bool testConstexpr()
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using year = std::chrono::year;
     ASSERT_NOEXCEPT(--(std::declval<year&>())  );
@@ -48,4 +48,6 @@ int main()
         assert(static_cast<int>(year--) == i - 1);
         assert(static_cast<int>(year)   == i - 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.members/increment.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.members/increment.pass.cpp
index 759fb66617bd2058e36dec7868c00160545cb174..ef2a6f3fbee67aea27e1b6e6a9f3b716a9b7bb7a 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.members/increment.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.members/increment.pass.cpp
@@ -30,7 +30,7 @@ constexpr bool testConstexpr()
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using year = std::chrono::year;
     ASSERT_NOEXCEPT(++(std::declval<year&>())  );
@@ -48,4 +48,6 @@ int main()
         assert(static_cast<int>(year++) == i + 1);
         assert(static_cast<int>(year)   == i + 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.members/is_leap.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.members/is_leap.pass.cpp
index b1785b86c59846d2138b10d5f8e4946b6707d771..37031dbbabc2d318241da87ca3be1470d5579f6a 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.members/is_leap.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.members/is_leap.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year = std::chrono::year;
 
@@ -49,4 +49,6 @@ int main()
     assert(!year{ 2003}.is_leap());
     assert( year{ 2004}.is_leap());
     assert(!year{ 2100}.is_leap());
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.members/ok.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.members/ok.pass.cpp
index dfc2ad3ffe45fe6acd19f96e095182a10c71103e..f56ee34d5983918b5cf0b465b31743445cb2a78a 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.members/ok.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.members/ok.pass.cpp
@@ -24,7 +24,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year = std::chrono::year;
 
@@ -49,4 +49,6 @@ int main()
     assert(year{ 20001}.ok());
 
     static_assert(!year{-32768}.ok(), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.members/plus_minus.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.members/plus_minus.pass.cpp
index 65b1494587bdad9455e62e91181a420495a15694..0adb0f9fe58a58aa73962b10aa351d9460d9c436 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.members/plus_minus.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.members/plus_minus.pass.cpp
@@ -28,7 +28,7 @@ constexpr bool testConstexpr()
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using year  = std::chrono::year;
 
@@ -46,4 +46,6 @@ int main()
         assert(static_cast<int>(+year) ==  i);
         assert(static_cast<int>(-year) == -i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.members/plus_minus_equal.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.members/plus_minus_equal.pass.cpp
index a00a36f2dcac5f8b52ca61ecf952349fadee20fc..b79713ed1c8a0badd5b887020398018d6523eaeb 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.members/plus_minus_equal.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.members/plus_minus_equal.pass.cpp
@@ -32,7 +32,7 @@ constexpr bool testConstexpr()
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using year  = std::chrono::year;
     using years = std::chrono::years;
@@ -53,4 +53,6 @@ int main()
         assert(static_cast<int>(year -= years{ 9}) == i +  1);
         assert(static_cast<int>(year)              == i +  1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.nonmembers/comparisons.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.nonmembers/comparisons.pass.cpp
index 8d675f4db3911df8af7d76742a6c063387acddec..9e84fe36ee0e7c954b2774e15e971160930daa98 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.nonmembers/comparisons.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.nonmembers/comparisons.pass.cpp
@@ -26,7 +26,7 @@
 #include "test_comparisons.h"
 
 
-int main()
+int main(int, char**)
 {
     using year = std::chrono::year;
 
@@ -43,4 +43,6 @@ int main()
     for (int i = 1; i < 10; ++i)
         for (int j = 1; j < 10; ++j)
             assert(testComparisons6Values<year>(i, j));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.nonmembers/literals.fail.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.nonmembers/literals.fail.cpp
index c6138c7af1c7212ebfb2ab22db4a3335a0050708..50c7b7bc0a613050eb6d6461cf98b2f095ff4d79 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.nonmembers/literals.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.nonmembers/literals.fail.cpp
@@ -20,8 +20,10 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using std::chrono::year;
     year d1 = 1234y; // expected-error-re {{no matching literal operator for call to 'operator""y' {{.*}}}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.nonmembers/literals.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.nonmembers/literals.pass.cpp
index 6ebd0e66fdde4c946cdb1155b98e7ec5ad5f1692..a2bec73e69656ae3d9800a23f4cc9808d1623a0d 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.nonmembers/literals.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.nonmembers/literals.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     using namespace std::chrono;
@@ -40,4 +40,6 @@ int main()
     std::chrono::year y1 = 2020y;
     assert (y1 == std::chrono::year(2020));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.nonmembers/minus.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.nonmembers/minus.pass.cpp
index 3e3e0b77db415c5889b1470aad8a2b087fe012da..f112345c0ad6c3fccb5ded7c7cd1c9caad79098e 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.nonmembers/minus.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.nonmembers/minus.pass.cpp
@@ -37,7 +37,7 @@ constexpr bool testConstexpr()
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using year  = std::chrono::year;
     using years = std::chrono::years;
@@ -58,4 +58,6 @@ int main()
         assert(static_cast<int>(y1) == 1223 - i);
         assert(ys1.count()          == 1223 - i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.nonmembers/plus.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.nonmembers/plus.pass.cpp
index 15c713defb43a20f68c7c1c9a44d5e050f2355a6..d73f6fc88b3b5541f1ebd108dc4cc54d11252c38 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.nonmembers/plus.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.nonmembers/plus.pass.cpp
@@ -33,7 +33,7 @@ constexpr bool testConstexpr()
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using year  = std::chrono::year;
     using years = std::chrono::years;
@@ -55,4 +55,6 @@ int main()
         assert(static_cast<int>(y1) == i + 1223);
         assert(static_cast<int>(y2) == i + 1223);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.nonmembers/streaming.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.nonmembers/streaming.pass.cpp
index 2c52cde0a43e0173acc9dd06e21aeb86bfd5be07..1b278f2b9033ebe4a9df5f493f766c95f0b3319a 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.nonmembers/streaming.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.year/time.cal.year.nonmembers/streaming.pass.cpp
@@ -46,9 +46,11 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
    using year = std::chrono::year;
 
    std::cout << year{2018};
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.year/types.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.year/types.pass.cpp
index 10bea23a035fb8e7b5294bd840fed56fbf41ddd4..2acb0f104d3bc388dcdc0858d97925b3fda6baed 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.year/types.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.year/types.pass.cpp
@@ -16,10 +16,12 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year = std::chrono::year;
 
     static_assert(std::is_trivially_copyable_v<year>, "");
     static_assert(std::is_standard_layout_v<year>, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.members/ctor.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.members/ctor.pass.cpp
index 090a1ac212c656430fe7c1e4efbed8b9f91490dc..1c05cf7a6b69846c791c961b0520bac6b90bc6d4 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.members/ctor.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.members/ctor.pass.cpp
@@ -25,7 +25,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year       = std::chrono::year;
     using month      = std::chrono::month;
@@ -48,4 +48,6 @@ int main()
     static_assert( ym2.year()  == year{2018}, "");
     static_assert( ym2.month() == month{},    "");
     static_assert(!ym2.ok(),                  "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.members/month.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.members/month.pass.cpp
index 97334b205033859e67caab28801921f1256e7a19..7e0cd17f4670cbf52048a83ed348b5303e59cfd5 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.members/month.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.members/month.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year       = std::chrono::year;
     using month      = std::chrono::month;
@@ -35,4 +35,6 @@ int main()
         year_month ym(year{1234}, month{i});
         assert( static_cast<unsigned>(ym.month()) == i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.members/ok.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.members/ok.pass.cpp
index 54e67dff9a3eb93452f1dce786fe05af5890e818..463289ee43f6bbefebd9094c4b02095597e5a1df 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.members/ok.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.members/ok.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using month      = std::chrono::month;
     using year       = std::chrono::year;
@@ -46,4 +46,6 @@ int main()
         year_month ym{year{i}, January};
         assert( ym.ok() == year{i}.ok());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.members/plus_minus_equal_month.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.members/plus_minus_equal_month.pass.cpp
index 76f3b3355d2221c0cea85d738737565cfd9e02e5..a403462ff797edc66c2efdf937d97aea73f6d97d 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.members/plus_minus_equal_month.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.members/plus_minus_equal_month.pass.cpp
@@ -32,7 +32,7 @@ constexpr bool testConstexpr(D d1)
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using month      = std::chrono::month;
     using months     = std::chrono::months;
@@ -60,4 +60,6 @@ int main()
         assert(static_cast<unsigned>((ym             ).month()) == i + 1);
         assert(ym.year() == y);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.members/plus_minus_equal_year.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.members/plus_minus_equal_year.pass.cpp
index 05cd60844d99b47577157c7a99ba7ed734915b6d..adf08fc24b820d55a606e661efa9f35b1f529de0 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.members/plus_minus_equal_year.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.members/plus_minus_equal_year.pass.cpp
@@ -32,7 +32,7 @@ constexpr bool testConstexpr(D d1)
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using month      = std::chrono::month;
     using year       = std::chrono::year;
@@ -61,4 +61,6 @@ int main()
         assert(static_cast<int>((ym            ).year()) == i + 1);
         assert(ym.month() == m);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.members/year.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.members/year.pass.cpp
index e8476b042809c62241d52d7b012d713ab152a013..024f3140425e3b30625a769b79a10b2ed4124015 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.members/year.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.members/year.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year       = std::chrono::year;
     using month      = std::chrono::month;
@@ -35,4 +35,6 @@ int main()
         year_month ym(year{i}, month{});
         assert( static_cast<int>(ym.year()) == i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.nonmembers/comparisons.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.nonmembers/comparisons.pass.cpp
index e1ab033c7c79c3b2f233ce36aa1f5570bd8dc11b..d102b0a5620a12b7b8cb9a66789ac938ac3200b6 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.nonmembers/comparisons.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.nonmembers/comparisons.pass.cpp
@@ -26,7 +26,7 @@
 #include "test_macros.h"
 #include "test_comparisons.h"
 
-int main()
+int main(int, char**)
 {
     using year       = std::chrono::year;
     using month      = std::chrono::month;
@@ -65,4 +65,6 @@ int main()
             year_month{year{i}, std::chrono::January},
             year_month{year{j}, std::chrono::January},
             i == j, i < j )));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.nonmembers/minus.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.nonmembers/minus.pass.cpp
index 2999560f16ff9361b70f3f07bfbc4ee761f9f2e5..d7756d10d258366052aae96d14c6e32d605bd3ba 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.nonmembers/minus.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.nonmembers/minus.pass.cpp
@@ -29,7 +29,7 @@
 
 #include <iostream>
 
-int main()
+int main(int, char**)
 {
     using year       = std::chrono::year;
     using years      = std::chrono::years;
@@ -86,4 +86,6 @@ int main()
 //  TODO: different year
 
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.nonmembers/plus.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.nonmembers/plus.pass.cpp
index dc721adeedbb6e73a35b6cab973ee9ed0024f877..5698e724470d83e8f2003d1b6942dd0b52e4b174 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.nonmembers/plus.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.nonmembers/plus.pass.cpp
@@ -51,7 +51,7 @@ constexpr bool testConstexprMonths(std::chrono::year_month ym)
 }
 
 
-int main()
+int main(int, char**)
 {
     using year       = std::chrono::year;
     using years      = std::chrono::years;
@@ -102,4 +102,6 @@ int main()
         assert(ym1 == ym2);
     }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.nonmembers/streaming.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.nonmembers/streaming.pass.cpp
index e75fc21bf889db774a854cad38624df313a877d5..43af6c2f7195ce873e6de389d601100815bdbae0 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.nonmembers/streaming.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ym/time.cal.ym.nonmembers/streaming.pass.cpp
@@ -46,11 +46,13 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year_month = std::chrono::year_month;
     using year       = std::chrono::year;
     using month      = std::chrono::month;
 
     std::cout << year_month{year{2018}, month{3}};
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ym/types.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ym/types.pass.cpp
index a3b9999f8fd898b718b188de3473551dcb998ab4..2e88c6bb6b60cbdf7fa7b6d59347b884d2ebf9fd 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ym/types.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ym/types.pass.cpp
@@ -16,10 +16,12 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year_month = std::chrono::year_month;
 
     static_assert(std::is_trivially_copyable_v<year_month>, "");
     static_assert(std::is_standard_layout_v<year_month>, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/ctor.local_days.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/ctor.local_days.pass.cpp
index 9cebaa6836ae280d12824d99f3da3ccb6e68a91d..274cb6a266fcb7fb4acd1ac2bcac1f8122bcc7d1 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/ctor.local_days.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/ctor.local_days.pass.cpp
@@ -29,7 +29,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year           = std::chrono::year;
     using day            = std::chrono::day;
@@ -81,4 +81,6 @@ int main()
     assert( ymd.month() == std::chrono::November);
     assert( ymd.day()   == day{29});
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/ctor.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/ctor.pass.cpp
index a5818849add2f385ecb23fac7a29b89c23369e50..fdef9517e4a45e6f7f37688b2987e9d330158904 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/ctor.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/ctor.pass.cpp
@@ -28,7 +28,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year           = std::chrono::year;
     using month          = std::chrono::month;
@@ -52,4 +52,6 @@ int main()
     static_assert( ym1.day()   == day{12},    "");
     static_assert( ym1.ok(),                  "");
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/ctor.sys_days.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/ctor.sys_days.pass.cpp
index 7344c10c1ad4a44b705b8ce5b2f23b920296636a..433468477d5d944ac2c11dcba2cae15caa28dd05 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/ctor.sys_days.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/ctor.sys_days.pass.cpp
@@ -28,7 +28,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year           = std::chrono::year;
     using day            = std::chrono::day;
@@ -80,4 +80,6 @@ int main()
     assert( ymd.month() == std::chrono::November);
     assert( ymd.day()   == day{29});
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/ctor.year_month_day_last.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/ctor.year_month_day_last.pass.cpp
index 913b403952b20b24b3d7efbf46f34861fd56ab94..d4e8fc83d5bbf31cb0989af05a167b082ae4cfa7 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/ctor.year_month_day_last.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/ctor.year_month_day_last.pass.cpp
@@ -26,7 +26,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year                = std::chrono::year;
     using month               = std::chrono::month;
@@ -76,4 +76,6 @@ int main()
     assert( ymd.day()   == day{28});
     assert( ymd.ok());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/day.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/day.pass.cpp
index 12e1515b1718c853b53269d044575f7dfd645a59..9a068737ddc41767380fed73fed65615b47a1e0b 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/day.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/day.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year           = std::chrono::year;
     using month          = std::chrono::month;
@@ -36,4 +36,6 @@ int main()
         year_month_day ymd(year{1234}, month{2}, day{i});
         assert( static_cast<unsigned>(ymd.day()) == i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/month.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/month.pass.cpp
index 8c091d0516532d4ef9e28c3bca5394aa6d72ab20..f1dd2e6893a9e98663dffdf64927f1d98f19e3b1 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/month.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/month.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year           = std::chrono::year;
     using month          = std::chrono::month;
@@ -36,4 +36,6 @@ int main()
         year_month_day ymd(year{1234}, month{i}, day{12});
         assert( static_cast<unsigned>(ymd.month()) == i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/ok.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/ok.pass.cpp
index edb55f58b4c6a6dde983a1fb31a7eeaa3761e1f1..cab639b820aa3faf6824206606d98975d13e9019 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/ok.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/ok.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year           = std::chrono::year;
     using month          = std::chrono::month;
@@ -92,4 +92,6 @@ int main()
         year_month_day ym{year{i}, January, day{12}};
         assert( ym.ok() == year{i}.ok());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/op.local_days.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/op.local_days.pass.cpp
index 02212dc9094a84832b1fc8217f110e707785b69a..038d21c4670c74c75b16be1edf2ee7ffe0dde687 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/op.local_days.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/op.local_days.pass.cpp
@@ -44,7 +44,7 @@ void RunTheExample()
     static_assert(year_month_day{local_days{year{2017}/January/32}} == year{2017}/February/1);  
 }
 
-int main()
+int main(int, char**)
 {
     using year           = std::chrono::year;
     using month          = std::chrono::month;
@@ -90,4 +90,5 @@ int main()
     assert( year_month_day{sd} == ymd); // and back
     }
 
+    return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/op.sys_days.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/op.sys_days.pass.cpp
index 5925cb0cb5cea18571dbaf98cc37d3cea256e403..a95684550859186b7d056ba6b5f0496510a97e1c 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/op.sys_days.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/op.sys_days.pass.cpp
@@ -44,7 +44,7 @@ void RunTheExample()
     static_assert(year_month_day{sys_days{year{2017}/January/32}} == year{2017}/February/1);  
 }
 
-int main()
+int main(int, char**)
 {
     using year           = std::chrono::year;
     using month          = std::chrono::month;
@@ -90,4 +90,5 @@ int main()
     assert( year_month_day{sd} == ymd); // and back
     }
 
+    return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/plus_minus_equal_month.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/plus_minus_equal_month.pass.cpp
index 173b8b6a2fbb7bf3e8e05b381c92347a9afe46f5..8530248d1d61c0c1a494fa615b169061402d94bd 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/plus_minus_equal_month.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/plus_minus_equal_month.pass.cpp
@@ -32,7 +32,7 @@ constexpr bool testConstexpr(D d1)
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using year           = std::chrono::year;
     using month          = std::chrono::month;
@@ -66,4 +66,6 @@ int main()
         assert(ym.year() == y);
         assert(ym.day()  == d);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/plus_minus_equal_year.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/plus_minus_equal_year.pass.cpp
index 1d99512915202e6cc6635c4f1b83da2cbfc1f458..ae134d1a24041e4353621951eb7e8d07d1785b8b 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/plus_minus_equal_year.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/plus_minus_equal_year.pass.cpp
@@ -32,7 +32,7 @@ constexpr bool testConstexpr(D d1)
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using year           = std::chrono::year;
     using month          = std::chrono::month;
@@ -66,4 +66,6 @@ int main()
         assert(ym.month() == m);
         assert(ym.day()   == d);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/year.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/year.pass.cpp
index 465fa9d93dbeea31fc07d288288be95992bab41f..fc5a407249363cca38c370ce498d7c2a4e78285d 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/year.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.members/year.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year           = std::chrono::year;
     using month          = std::chrono::month;
@@ -36,4 +36,6 @@ int main()
         year_month_day ym(year{i}, month{}, day{});
         assert( static_cast<int>(ym.year()) == i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.nonmembers/comparisons.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.nonmembers/comparisons.pass.cpp
index 8d5bf89553cddbde931922d6ace426a88b12e36b..0d15589252a1c0359c4d5b5de4ea2893242bc3ad 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.nonmembers/comparisons.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.nonmembers/comparisons.pass.cpp
@@ -29,7 +29,7 @@
 #include "test_macros.h"
 #include "test_comparisons.h"
 
-int main()
+int main(int, char**)
 {
     using day        = std::chrono::day;
     using year       = std::chrono::year;
@@ -114,4 +114,6 @@ int main()
             year_month_day{year{i}, January, day{12}},
             year_month_day{year{j}, January, day{12}},
             i == j, i < j )));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.nonmembers/minus.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.nonmembers/minus.pass.cpp
index 4d5625ba7396a39fdf77ef82b522c955a0b10ead..3c921def3b8865857f884fb6eda78e0dc020d0a8 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.nonmembers/minus.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.nonmembers/minus.pass.cpp
@@ -33,7 +33,7 @@ constexpr bool test_constexpr ()
         ;
 }
 
-int main()
+int main(int, char**)
 {
     using year           = std::chrono::year;
     using month          = std::chrono::month;
@@ -56,4 +56,6 @@ int main()
         assert(ym1.month() == January);
         assert(ym1.day() == day{10});
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.nonmembers/plus.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.nonmembers/plus.pass.cpp
index 2913eb2374316ef7e853a7fb247ff7f6bab944fd..8d5e02543aaa65adb4e3aca7319b5c0a5937a96a 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.nonmembers/plus.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.nonmembers/plus.pass.cpp
@@ -51,7 +51,7 @@ constexpr bool testConstexprMonths(std::chrono::year_month_day ym)
 }
 
 
-int main()
+int main(int, char**)
 {
     using day        = std::chrono::day;
     using year       = std::chrono::year;
@@ -108,4 +108,6 @@ int main()
     }
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.nonmembers/streaming.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.nonmembers/streaming.pass.cpp
index cce42bc616dbe29703b7553c9cb391c83bffd9e5..47b6f02490d95b6a381d4f9e43df9fdca9f83303 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.nonmembers/streaming.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.nonmembers/streaming.pass.cpp
@@ -46,7 +46,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year_month_day = std::chrono::year_month_day;
     using year           = std::chrono::year;
@@ -54,4 +54,6 @@ int main()
     using day            = std::chrono::day;
 
     std::cout << year_month_day{year{2018}, month{3}, day{12}};
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/types.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/types.pass.cpp
index c61d1c9960f6af6b04f9ca1bb0c9c8af1a1cd7d3..58acd143df9d57d83fd608e62c6101d02b1bcd86 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/types.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymd/types.pass.cpp
@@ -16,10 +16,12 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year_month_day = std::chrono::year_month_day;
 
     static_assert(std::is_trivially_copyable_v<year_month_day>, "");
     static_assert(std::is_standard_layout_v<year_month_day>, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/ctor.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/ctor.pass.cpp
index d27c3c67e5ec1733a541ae9be391c41a4fbe27f0..bd4729f6a0ef35a4d14c0252add9e70ba7ec04b2 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/ctor.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/ctor.pass.cpp
@@ -27,7 +27,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year                = std::chrono::year;
     using month               = std::chrono::month;
@@ -49,4 +49,6 @@ int main()
     static_assert( ymdl1.month()          == January,                 "");
     static_assert( ymdl1.month_day_last() == month_day_last{January}, "");
     static_assert( ymdl1.ok(),                                        "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/day.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/day.pass.cpp
index 24682b6957fccc97f5e978d3030b4a7dfdc83e21..2f0e2ba17a7a9aa6a494b36eb765fcb711e5194d 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/day.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/day.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year                = std::chrono::year;
     using month               = std::chrono::month;
@@ -47,4 +47,6 @@ int main()
     assert((year_month_day_last{year{2019}, month_day_last{month{ 2}}}.day() == day{28}));
     assert((year_month_day_last{year{2020}, month_day_last{month{ 2}}}.day() == day{29}));
     assert((year_month_day_last{year{2021}, month_day_last{month{ 2}}}.day() == day{28}));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/month.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/month.pass.cpp
index cf1024a8ce3e350a5d4ec454c7c54d3d4581cf07..5b68aa1d95cb730094ee736a8111183b8a1f2229 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/month.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/month.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year                = std::chrono::year;
     using month               = std::chrono::month;
@@ -34,4 +34,6 @@ int main()
         year_month_day_last ymd(year{1234}, month_day_last{month{i}});
         assert( static_cast<unsigned>(ymd.month()) == i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/month_day_last.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/month_day_last.pass.cpp
index 5c99d947124d01b1e425f3d257aa2a9316fbb8e2..cca9026b650b5f59da80c073995bdb2e3bf039cd 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/month_day_last.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/month_day_last.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year                = std::chrono::year;
     using month               = std::chrono::month;
@@ -34,4 +34,6 @@ int main()
         year_month_day_last ymdl(year{1234}, month_day_last{month{i}});
         assert( static_cast<unsigned>(ymdl.month_day_last().month()) == i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/ok.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/ok.pass.cpp
index bb4c410d449f895d1acb1d74796a25f80357897f..d40de103c2ab26be7a754ddcfa1727684851a549 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/ok.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/ok.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year                = std::chrono::year;
     using month               = std::chrono::month;
@@ -48,4 +48,6 @@ int main()
         year_month_day_last ym{year{i}, month_day_last{January}};
         assert( ym.ok() == year{i}.ok());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/op_local_days.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/op_local_days.pass.cpp
index 83f8b70dc79b8ab008f9f50763c51b401cd07880..a96dff338bea296fccb8f288c21899e2e4dfecde 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/op_local_days.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/op_local_days.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year                = std::chrono::year;
     using month_day_last      = std::chrono::month_day_last;
@@ -57,4 +57,6 @@ int main()
 
     assert(sd.time_since_epoch() == days{-(10957+33)});
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/op_sys_days.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/op_sys_days.pass.cpp
index 9a32112c901fcd4df44cbec2637706bab8e04453..250ca0f11239577629b1b4eeb0fa0f5400ac4fdc 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/op_sys_days.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/op_sys_days.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year                = std::chrono::year;
     using month_day_last      = std::chrono::month_day_last;
@@ -57,4 +57,6 @@ int main()
 
     assert(sd.time_since_epoch() == days{-(10957+33)});
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/plus_minus_equal_month.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/plus_minus_equal_month.pass.cpp
index 2c4d1ff1f1708114e319efacffe694e80c836571..7091f64ea339b26e7efff4e6fdd6f1b224c88fa4 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/plus_minus_equal_month.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/plus_minus_equal_month.pass.cpp
@@ -32,7 +32,7 @@ constexpr bool testConstexpr(D d1)
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using year                = std::chrono::year;
     using month               = std::chrono::month;
@@ -62,4 +62,6 @@ int main()
         assert(static_cast<unsigned>((ym             ).month()) == i + 1);
         assert(ym.year() == y);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/plus_minus_equal_year.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/plus_minus_equal_year.pass.cpp
index 00335e15d54fa3e8332892a6a81355933a65c6c2..3c1ad352737bc7b66cdc7ecf9dab881892a4dd6f 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/plus_minus_equal_year.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/plus_minus_equal_year.pass.cpp
@@ -32,7 +32,7 @@ constexpr bool testConstexpr(D d1)
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using year                = std::chrono::year;
     using month               = std::chrono::month;
@@ -61,4 +61,6 @@ int main()
         assert(static_cast<int>((ymdl            ).year()) == i + 1);
         assert(ymdl.month_day_last() == mdl);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/year.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/year.pass.cpp
index 49387091d761ab5f8fa15c4c0dbe98dfe6dce6d7..c0db150f96d55012f6690c613b3214396d2c8398 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/year.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.members/year.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year                = std::chrono::year;
     using month               = std::chrono::month;
@@ -34,4 +34,6 @@ int main()
         year_month_day_last ym(year{i}, month_day_last{month{}});
         assert( static_cast<int>(ym.year()) == i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.nonmembers/comparisons.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.nonmembers/comparisons.pass.cpp
index 9db4b6aa6d929542752ceb46d083abe9b2b0284d..c56491f96cb2c14071c3d128841ed76c28918787 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.nonmembers/comparisons.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.nonmembers/comparisons.pass.cpp
@@ -26,7 +26,7 @@
 #include "test_macros.h"
 #include "test_comparisons.h"
 
-int main()
+int main(int, char**)
 {
     using year                = std::chrono::year;
     using month               = std::chrono::month;
@@ -83,4 +83,6 @@ int main()
             year_month_day_last{year{i}, month_day_last{January}},
             year_month_day_last{year{j}, month_day_last{January}},
             i == j, i < j )));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.nonmembers/minus.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.nonmembers/minus.pass.cpp
index 7f5a796dfab26ad705cf933aa1824cd58a0325ee..8ea3025d6070b597fe0221c002038be282a8a581 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.nonmembers/minus.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.nonmembers/minus.pass.cpp
@@ -47,7 +47,7 @@ constexpr bool testConstexprMonths (std::chrono::year_month_day_last ymdl)
         ;
 }
 
-int main()
+int main(int, char**)
 {
     using year                = std::chrono::year;
     using month               = std::chrono::month;
@@ -87,4 +87,6 @@ int main()
     }
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.nonmembers/plus.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.nonmembers/plus.pass.cpp
index c494620df6e4e81ad4a6d631d173fac3ff98f8a7..75cabbdcd28029d3a3f3d69c06cf81a6dfa40f49 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.nonmembers/plus.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.nonmembers/plus.pass.cpp
@@ -63,7 +63,7 @@ constexpr bool testConstexprMonths(std::chrono::year_month_day_last ymdl)
 }
 
 
-int main()
+int main(int, char**)
 {
     using year                = std::chrono::year;
     using month               = std::chrono::month;
@@ -118,4 +118,6 @@ int main()
     }
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.nonmembers/streaming.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.nonmembers/streaming.pass.cpp
index 268eb88fe172eb55f787401001e7173a5adf429d..eca8d3d68518bf7189bf0004422b65fedbe10529 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.nonmembers/streaming.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.nonmembers/streaming.pass.cpp
@@ -25,7 +25,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year_month_day_last = std::chrono::year_month_day_last;
     using year                = std::chrono::year;
@@ -33,4 +33,6 @@ int main()
     using month_day_last      = std::chrono::month_day_last;
 
     std::cout << year_month_day_last{year{2018}, month_day_last{month{3}}};
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/ctor.local_days.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/ctor.local_days.pass.cpp
index 0eae24e459cff4b96de7f94acaea4742dae72d8d..bb4e7d0440547169281cf89c60996d93e4930402 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/ctor.local_days.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/ctor.local_days.pass.cpp
@@ -29,7 +29,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year               = std::chrono::year;
     using days               = std::chrono::days;
@@ -91,4 +91,6 @@ int main()
     assert((ymwd.weekday_indexed() == weekday_indexed{std::chrono::Wednesday, 5}));
     assert( ymwd                   == year_month_weekday{local_days{ymwd}}); // round trip
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/ctor.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/ctor.pass.cpp
index dab8b21577bac88d064ea10669e8861427911e68..81030ff559d213749636066962ccb0f7f342dcaf 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/ctor.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/ctor.pass.cpp
@@ -30,7 +30,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year               = std::chrono::year;
     using month              = std::chrono::month;
@@ -60,4 +60,6 @@ int main()
     static_assert( ym1.weekday_indexed() == weekday_indexed{Tuesday, 1}, "");
     static_assert( ym1.ok(),                                             "");
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/ctor.sys_days.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/ctor.sys_days.pass.cpp
index 96261c54e3c9b2162f751e84afdd3d3b730fcc5d..5ae9900a9834e207266cdc8a28790da0ff0638f8 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/ctor.sys_days.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/ctor.sys_days.pass.cpp
@@ -28,7 +28,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year               = std::chrono::year;
     using days               = std::chrono::days;
@@ -90,4 +90,6 @@ int main()
     assert((ymwd.weekday_indexed() == weekday_indexed{std::chrono::Wednesday, 5}));
     assert( ymwd                   == year_month_weekday{sys_days{ymwd}}); // round trip
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/index.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/index.pass.cpp
index 4c0bc13c1868f0cdac27ddc5c060edafad1e2a60..ecbd8aec8302ae1d6e09d151ae978cd94662b296 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/index.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/index.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year               = std::chrono::year;
     using month              = std::chrono::month;
@@ -37,4 +37,6 @@ int main()
         year_month_weekday ymwd0(year{1234}, month{2}, weekday_indexed{weekday{2}, i});
         assert(ymwd0.index() == i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/month.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/month.pass.cpp
index 0e2d41a771fe610110754f3734f1e3b95b32ccba..c300fd5d36afd97948584dd3244aa8ddc28a7568 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/month.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/month.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year               = std::chrono::year;
     using month              = std::chrono::month;
@@ -36,4 +36,6 @@ int main()
         year_month_weekday ymd(year{1234}, month{i}, weekday_indexed{});
         assert( static_cast<unsigned>(ymd.month()) == i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/ok.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/ok.pass.cpp
index f66d6a083c425ca83dae2c90e20598ffdbb3efad..7e8599e0509ddb368a5b850f90a148fae7a12fad 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/ok.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/ok.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year               = std::chrono::year;
     using month              = std::chrono::month;
@@ -71,4 +71,6 @@ int main()
         year_month_weekday ym{year{i}, January, weekday_indexed{Tuesday, 1}};
         assert((ym.ok() == year{i}.ok()));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/op.local_days.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/op.local_days.pass.cpp
index 788af653555616bfb5fe612f572dc271c27f6360..e86e5b0fa6e3764f228442a39202d9bc8312e33d 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/op.local_days.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/op.local_days.pass.cpp
@@ -25,7 +25,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year               = std::chrono::year;
     using month              = std::chrono::month;
@@ -70,4 +70,5 @@ int main()
     assert( year_month_weekday{sd} == ymwd); // and back
     }
 
+    return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/op.sys_days.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/op.sys_days.pass.cpp
index 111cf5f38db87dabc3f072fd198244ce650c9e59..afb1d70148adfeef3a611303984619290c01d0ae 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/op.sys_days.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/op.sys_days.pass.cpp
@@ -25,7 +25,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year               = std::chrono::year;
     using month              = std::chrono::month;
@@ -70,4 +70,5 @@ int main()
     assert( year_month_weekday{sd} == ymwd); // and back
     }
 
+    return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/plus_minus_equal_month.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/plus_minus_equal_month.pass.cpp
index 7e20a8eb05a286fb0338273d8992248b16b43065..fd53279ddde2ee878bc44f1827b8e67b0d0be375 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/plus_minus_equal_month.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/plus_minus_equal_month.pass.cpp
@@ -32,7 +32,7 @@ constexpr bool testConstexpr(D d1)
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using year               = std::chrono::year;
     using month              = std::chrono::month;
@@ -76,4 +76,6 @@ int main()
         assert(ymwd.weekday()  == Tuesday);
         assert(ymwd.index()    == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/plus_minus_equal_year.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/plus_minus_equal_year.pass.cpp
index 4deee9bc35d064cd0e6fbce2ad0e58ccfe79812d..cf229febe08394b466dcd3217d3107c9a9dbb3c1 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/plus_minus_equal_year.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/plus_minus_equal_year.pass.cpp
@@ -32,7 +32,7 @@ constexpr bool testConstexpr(D d1)
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using year               = std::chrono::year;
     using month              = std::chrono::month;
@@ -76,4 +76,6 @@ int main()
         assert(ymwd.weekday()  == Tuesday);
         assert(ymwd.index()    == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/weekday.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/weekday.pass.cpp
index 1b9c8ad1041e01fce5af63ebd837fee9f9157b35..dac1f7cc0490a7916d056ef1ccabe2b9a8112711 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/weekday.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/weekday.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year               = std::chrono::year;
     using month              = std::chrono::month;
@@ -37,4 +37,6 @@ int main()
         year_month_weekday ymwd0(year{1234}, month{2}, weekday_indexed{weekday{i}, 1});
         assert(static_cast<unsigned>(ymwd0.weekday()) == i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/weekday_indexed.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/weekday_indexed.pass.cpp
index 4a9832323f154b8affb57bee773e9054c48faca8..f089a8cb93e1f6a2e79441318814d229967fb747 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/weekday_indexed.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/weekday_indexed.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year               = std::chrono::year;
     using month              = std::chrono::month;
@@ -41,4 +41,6 @@ int main()
         assert( static_cast<unsigned>(ymwd1.weekday_indexed().weekday()) == 2);
         assert( static_cast<unsigned>(ymwd1.weekday_indexed().index()) == i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/year.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/year.pass.cpp
index 8103c28aa60f54e5ab6054b6105da5f1edeed7b2..1ead67570cf38b2f95d4e9f4c838c2c357d7858d 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/year.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.members/year.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year               = std::chrono::year;
     using month              = std::chrono::month;
@@ -36,4 +36,6 @@ int main()
         year_month_weekday ym(year{i}, month{1}, weekday_indexed{});
         assert( static_cast<int>(ym.year()) == i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.nonmembers/comparisons.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.nonmembers/comparisons.pass.cpp
index 847699b25165cecd46331f37c2aca6a6ec13d5ed..5631127222b1f13a1cfdf042086e25d946b167b8 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.nonmembers/comparisons.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.nonmembers/comparisons.pass.cpp
@@ -22,7 +22,7 @@
 #include "test_macros.h"
 #include "test_comparisons.h"
 
-int main()
+int main(int, char**)
 {
     using year               = std::chrono::year;
     using month              = std::chrono::month;
@@ -109,4 +109,6 @@ int main()
             year_month_weekday{year{i}, January, weekday_indexed{Tuesday, 1}},
             year_month_weekday{year{j}, January, weekday_indexed{Tuesday, 1}},
             i == j)));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.nonmembers/minus.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.nonmembers/minus.pass.cpp
index ff472fdc6ceb1b88d9600750ef028bd5863702e9..47cfbea6a679473ce4a88e9935d22d66307acc3d 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.nonmembers/minus.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.nonmembers/minus.pass.cpp
@@ -50,7 +50,7 @@ constexpr bool testConstexprMonths ()
 }
 
 
-int main()
+int main(int, char**)
 {
     using year               = std::chrono::year;
     using month              = std::chrono::month;
@@ -96,4 +96,6 @@ int main()
         assert(ym1.index()   == 2);
     }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.nonmembers/plus.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.nonmembers/plus.pass.cpp
index bc72d958ca07a26ddbf1e1a7a47c5ae8bf5491f0..29df4776e2bf5b1e0b45b4a1b0c273c4439184a2 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.nonmembers/plus.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.nonmembers/plus.pass.cpp
@@ -51,7 +51,7 @@ constexpr bool testConstexprMonths(std::chrono::year_month_weekday ym)
 }
 
 
-int main()
+int main(int, char**)
 {
     using year               = std::chrono::year;
     using month              = std::chrono::month;
@@ -116,4 +116,6 @@ int main()
     }
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.nonmembers/streaming.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.nonmembers/streaming.pass.cpp
index eb92cf05e47a473b9059312968488f0815c88c41..411e4335fd0d282828dff443b868b348f718f3c7 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.nonmembers/streaming.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.nonmembers/streaming.pass.cpp
@@ -45,7 +45,7 @@
 #include <iostream>
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year_month_weekday = std::chrono::year_month_weekday;
     using year                = std::chrono::year;
@@ -53,4 +53,6 @@ int main()
     using weekday             = std::chrono::weekday;
 
     std::cout << year_month_weekday{year{2018}, month{3}, weekday{4}};
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/types.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/types.pass.cpp
index 449098c4f18bf6cb81c3c8f149abe286d8db334e..76e2e0f237e6b3d0e1b11cc5f1d25023bec1abf1 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/types.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwd/types.pass.cpp
@@ -16,10 +16,12 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year_month_weekday = std::chrono::year_month_weekday;
 
     static_assert(std::is_trivially_copyable_v<year_month_weekday>, "");
     static_assert(std::is_standard_layout_v<year_month_weekday>, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/ctor.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/ctor.pass.cpp
index 1db6850dbcec41975968154c3836d046af960871..31d2e9ca7061fe66bb74be669c57944a4e96bce6 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/ctor.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/ctor.pass.cpp
@@ -28,7 +28,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year                    = std::chrono::year;
     using month                   = std::chrono::month;
@@ -48,4 +48,6 @@ int main()
     static_assert( ym1.weekday_last() == weekday_last{Tuesday}, "");
     static_assert( ym1.ok(),                                    "");
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/month.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/month.pass.cpp
index 7b95084b214ca06c98f809fe13ec96c0ae1d4029..df62d010ab6413c2d17c76f05c1caab9bde8f0e5 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/month.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/month.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year                    = std::chrono::year;
     using month                   = std::chrono::month;
@@ -37,4 +37,6 @@ int main()
         year_month_weekday_last ymd(year{1234}, month{i}, weekday_last{weekday{}});
         assert( static_cast<unsigned>(ymd.month()) == i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/ok.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/ok.pass.cpp
index 1cffb4565b7f91892c7cfbe94aab975dc34ee23b..c18b926704c721b7ecfa1c01e811745c9bb289aa 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/ok.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/ok.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year                    = std::chrono::year;
     using month                   = std::chrono::month;
@@ -69,4 +69,6 @@ int main()
         year_month_weekday_last ym{year{i}, January, weekday_last{Tuesday}};
         assert((ym.ok() == year{i}.ok()));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/op_local_days.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/op_local_days.pass.cpp
index 83f8b70dc79b8ab008f9f50763c51b401cd07880..c663406ee43ecc267398bd0f534d363e07563be4 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/op_local_days.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/op_local_days.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year                = std::chrono::year;
     using month_day_last      = std::chrono::month_day_last;
@@ -57,4 +57,6 @@ int main()
 
     assert(sd.time_since_epoch() == days{-(10957+33)});
     }
+
+    return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/op_sys_days.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/op_sys_days.pass.cpp
index cc3da2992e831daa5b0317fe0f30d6593fd965eb..cb75842c64c2766e6c0807d787fdd3c312fd12ef 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/op_sys_days.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/op_sys_days.pass.cpp
@@ -22,7 +22,7 @@
 
 #include <iostream>
 
-int main()
+int main(int, char**)
 {
     using year                    = std::chrono::year;
     using month                   = std::chrono::month;
@@ -65,4 +65,6 @@ int main()
 
     assert(sd.time_since_epoch() == days{-(10957+35)});
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/plus_minus_equal_month.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/plus_minus_equal_month.pass.cpp
index ad513c5d0cf4187f9c8a6f185ac103a1cca5983f..b2bb1361b6b9c05b8107e84125b2a8d98e4dca88 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/plus_minus_equal_month.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/plus_minus_equal_month.pass.cpp
@@ -32,7 +32,7 @@ constexpr bool testConstexpr(D d1)
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using year                    = std::chrono::year;
     using month                   = std::chrono::month;
@@ -71,4 +71,6 @@ int main()
         assert(ymwd.year()     == y);
         assert(ymwd.weekday()  == Tuesday);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/plus_minus_equal_year.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/plus_minus_equal_year.pass.cpp
index 7d9255fe494f65eb69b1909acae2a51e43c414c3..8ced182d6c8e5fef0a5fa0d461cd54b05cdae6b5 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/plus_minus_equal_year.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/plus_minus_equal_year.pass.cpp
@@ -32,7 +32,7 @@ constexpr bool testConstexpr(D d1)
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using year                    = std::chrono::year;
     using month                   = std::chrono::month;
@@ -72,4 +72,6 @@ int main()
         assert(ymwd.month()    == January);
         assert(ymwd.weekday()  == Tuesday);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/weekday.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/weekday.pass.cpp
index cc0521354f9c457b35f02a4104e3863d484457d9..1de0b8323098732c074d160eaa3a4747619407fb 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/weekday.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/weekday.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year                    = std::chrono::year;
     using month                   = std::chrono::month;
@@ -37,4 +37,6 @@ int main()
         year_month_weekday_last ymwdl(year{1}, month{1}, weekday_last{weekday{i}});
         assert(static_cast<unsigned>(ymwdl.weekday()) == i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/year.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/year.pass.cpp
index 4011f0673ff5e19dd4a7c3a7577665e15ec15194..4e940791145574132a7e07216bd23e721af4e08b 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/year.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.members/year.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year                    = std::chrono::year;
     using month                   = std::chrono::month;
@@ -37,4 +37,6 @@ int main()
         year_month_weekday_last ymwdl(year{i}, month{1}, weekday_last{weekday{}});
         assert(static_cast<int>(ymwdl.year()) == i);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.nonmembers/comparisons.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.nonmembers/comparisons.pass.cpp
index a13b11f8c10e1ba7daab27698bf40cb3c8580818..24074f33cbcb95248594d17f7b01ac66dc4f71de 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.nonmembers/comparisons.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.nonmembers/comparisons.pass.cpp
@@ -22,7 +22,7 @@
 #include "test_macros.h"
 #include "test_comparisons.h"
 
-int main()
+int main(int, char**)
 {
     using year                    = std::chrono::year;
     using month                   = std::chrono::month;
@@ -110,4 +110,6 @@ int main()
             year_month_weekday_last{year{i}, January, weekday_last{Tuesday}},
             year_month_weekday_last{year{j}, January, weekday_last{Tuesday}},
             i == j)));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.nonmembers/minus.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.nonmembers/minus.pass.cpp
index 20a58152f33e5bcf45602a7c11322d1408a3d930..d58c461be8b37f0d62199c431fdf7b5233402d02 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.nonmembers/minus.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.nonmembers/minus.pass.cpp
@@ -40,7 +40,7 @@ constexpr bool testConstexprMonths(std::chrono::year_month_weekday_last ym)
     return true;
 }
 
-int main()
+int main(int, char**)
 {
     using year                    = std::chrono::year;
     using month                   = std::chrono::month;
@@ -89,4 +89,6 @@ int main()
     }
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.nonmembers/plus.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.nonmembers/plus.pass.cpp
index 45dd7562dc0f37ff974dda6b04fe06cc605b3a94..fe246cf42ba81667a97b6c2e92d2b1ddb16ae55c 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.nonmembers/plus.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.nonmembers/plus.pass.cpp
@@ -47,7 +47,7 @@ constexpr bool testConstexprMonths(std::chrono::year_month_weekday_last ym)
 }
 
 
-int main()
+int main(int, char**)
 {
     using year                    = std::chrono::year;
     using month                   = std::chrono::month;
@@ -112,4 +112,6 @@ int main()
     }
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.nonmembers/streaming.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.nonmembers/streaming.pass.cpp
index 6e4409c7138eb5b90f75994085864af0e9fce7aa..cdfe55f16509152ff24cc991cb5db7a3ca96f03e 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.nonmembers/streaming.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.nonmembers/streaming.pass.cpp
@@ -25,7 +25,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year_month_weekday_last = std::chrono::year_month_weekday_last;
     using year                    = std::chrono::year;
@@ -34,4 +34,6 @@ int main()
     using weekday_last            = std::chrono::weekday_last;
 
     std::cout << year_month_weekday_last{year{2018}, month{3}, weekday_last{weekday{4}}};
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/types.pass.cpp b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/types.pass.cpp
index e0580fac76fa9102f0058519d247d1d7895bce5a..70dea7bf922c4b3e4ee63f452c4150f8700eb84b 100644
--- a/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/types.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.cal/time.cal.ymwdlast/types.pass.cpp
@@ -16,10 +16,12 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using year_month_weekday_last = std::chrono::year_month_weekday_last;
 
     static_assert(std::is_trivially_copyable_v<year_month_weekday_last>, "");
     static_assert(std::is_standard_layout_v<year_month_weekday_last>, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.clock.req/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/time/time.clock.req/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/time/time.clock.req/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.clock.req/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.clock/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/time/time.clock/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/time/time.clock/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.clock/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.clock/time.clock.file/consistency.pass.cpp b/libcxx/test/std/utilities/time/time.clock/time.clock.file/consistency.pass.cpp
index 332d8163cb6fdf215fa0e7bc9094fea33e2be76a..165bec2e117b26b1d74c3061c9cde05b8205bfe9 100644
--- a/libcxx/test/std/utilities/time/time.clock/time.clock.file/consistency.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.clock/time.clock.file/consistency.pass.cpp
@@ -22,7 +22,7 @@
 template <class T>
 void test(const T &) {}
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::file_clock C;
     static_assert((std::is_same<C::rep, C::duration::rep>::value), "");
@@ -31,4 +31,6 @@ int main()
     static_assert((std::is_same<C::time_point::clock, C>::value), "");
     static_assert(!C::is_steady, "");
     test(std::chrono::file_clock::is_steady);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.clock/time.clock.file/file_time.pass.cpp b/libcxx/test/std/utilities/time/time.clock/time.clock.file/file_time.pass.cpp
index 75652f3ecd0abfe8dc5912175f030181ffe67e94..61d92381fc8c017c6fbd45ae7bbfc2bc13c95b2b 100644
--- a/libcxx/test/std/utilities/time/time.clock/time.clock.file/file_time.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.clock/time.clock.file/file_time.pass.cpp
@@ -21,8 +21,10 @@ void test() {
   ASSERT_SAME_TYPE(std::chrono::file_time<Dur>, std::chrono::time_point<std::chrono::file_clock, Dur>);
 }
 
-int main() {
+int main(int, char**) {
   test<std::chrono::nanoseconds>();
   test<std::chrono::minutes>();
   test<std::chrono::hours>();
+
+  return 0;
 }
\ No newline at end of file
diff --git a/libcxx/test/std/utilities/time/time.clock/time.clock.file/now.pass.cpp b/libcxx/test/std/utilities/time/time.clock/time.clock.file/now.pass.cpp
index 3b51b91b501aa880dfad51a9682b3f6a70f17404..79cdf06120ca2c2234b1ca93831ad71861aba9c1 100644
--- a/libcxx/test/std/utilities/time/time.clock/time.clock.file/now.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.clock/time.clock.file/now.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::file_clock C;
     ASSERT_NOEXCEPT(C::now());
@@ -31,4 +31,6 @@ int main()
     assert(t1.time_since_epoch().count() != 0);
     assert(C::time_point::min() < t1);
     assert(C::time_point::max() > t1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.clock/time.clock.file/rep_signed.pass.cpp b/libcxx/test/std/utilities/time/time.clock/time.clock.file/rep_signed.pass.cpp
index c36649a5d414d22ac093d804f723c814ca94ce6d..821072e6df6c6c4114f79220e0d80f0706f0980b 100644
--- a/libcxx/test/std/utilities/time/time.clock/time.clock.file/rep_signed.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.clock/time.clock.file/rep_signed.pass.cpp
@@ -20,9 +20,11 @@
 #include <chrono>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     static_assert(std::is_signed<std::chrono::file_clock::rep>::value, "");
     assert(std::chrono::file_clock::duration::min() <
            std::chrono::file_clock::duration::zero());
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.clock/time.clock.hires/consistency.pass.cpp b/libcxx/test/std/utilities/time/time.clock/time.clock.hires/consistency.pass.cpp
index 6f06e718e257b6d4987b667f427f853b5879b95a..1650d3b6b5f3ea9225b734cd3acf497b7dbdf693 100644
--- a/libcxx/test/std/utilities/time/time.clock/time.clock.hires/consistency.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.clock/time.clock.hires/consistency.pass.cpp
@@ -27,7 +27,7 @@
 template <class T>
 void test(const T &) {}
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::high_resolution_clock C;
     static_assert((std::is_same<C::rep, C::duration::rep>::value), "");
@@ -35,4 +35,6 @@ int main()
     static_assert((std::is_same<C::duration, C::time_point::duration>::value), "");
     static_assert(C::is_steady || !C::is_steady, "");
     test(std::chrono::high_resolution_clock::is_steady);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.clock/time.clock.hires/now.pass.cpp b/libcxx/test/std/utilities/time/time.clock/time.clock.hires/now.pass.cpp
index c1d879c6f3b0006cda616bdc4413c930e5ed6105..ddf3ced87dac1bbf689f0375ae6a303712579c24 100644
--- a/libcxx/test/std/utilities/time/time.clock/time.clock.hires/now.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.clock/time.clock.hires/now.pass.cpp
@@ -15,11 +15,13 @@
 #include <chrono>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::high_resolution_clock C;
     C::time_point t1 = C::now();
     assert(t1.time_since_epoch().count() != 0);
     assert(C::time_point::min() < t1);
     assert(C::time_point::max() > t1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.clock/time.clock.steady/consistency.pass.cpp b/libcxx/test/std/utilities/time/time.clock/time.clock.steady/consistency.pass.cpp
index 1577bc180086e8f83791b6e221a2137ec1dacae8..0797f2cb5bcf111b3641fa180d0b2df2cc837fa0 100644
--- a/libcxx/test/std/utilities/time/time.clock/time.clock.steady/consistency.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.clock/time.clock.steady/consistency.pass.cpp
@@ -29,7 +29,7 @@
 template <class T>
 void test(const T &) {}
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::steady_clock C;
     static_assert((std::is_same<C::rep, C::duration::rep>::value), "");
@@ -37,4 +37,6 @@ int main()
     static_assert((std::is_same<C::duration, C::time_point::duration>::value), "");
     static_assert(C::is_steady, "");
     test(std::chrono::steady_clock::is_steady);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.clock/time.clock.steady/now.pass.cpp b/libcxx/test/std/utilities/time/time.clock/time.clock.steady/now.pass.cpp
index 248f1523f87f86d663fd2273bd479fbb7d32f078..7d268fd67ded9d391fa4f21c2b5c1efde63fac3d 100644
--- a/libcxx/test/std/utilities/time/time.clock/time.clock.steady/now.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.clock/time.clock.steady/now.pass.cpp
@@ -17,10 +17,12 @@
 #include <chrono>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::steady_clock C;
     C::time_point t1 = C::now();
     C::time_point t2 = C::now();
     assert(t2 >= t1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.clock/time.clock.system/consistency.pass.cpp b/libcxx/test/std/utilities/time/time.clock/time.clock.system/consistency.pass.cpp
index b15a8e2124d9b1920031d80ff767f537a0c81206..b92652134ad6a907689fccb6d3ca019554e1273d 100644
--- a/libcxx/test/std/utilities/time/time.clock/time.clock.system/consistency.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.clock/time.clock.system/consistency.pass.cpp
@@ -27,7 +27,7 @@
 template <class T>
 void test(const T &) {}
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::system_clock C;
     static_assert((std::is_same<C::rep, C::duration::rep>::value), "");
@@ -36,4 +36,6 @@ int main()
     static_assert((std::is_same<C::time_point::clock, C>::value), "");
     static_assert((C::is_steady || !C::is_steady), "");
     test(std::chrono::system_clock::is_steady);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.clock/time.clock.system/from_time_t.pass.cpp b/libcxx/test/std/utilities/time/time.clock/time.clock.system/from_time_t.pass.cpp
index e6acef241c68e9276184cc0f1856073021e16771..54252718d4af14ded1722f38b4cba2d0afb4a46f 100644
--- a/libcxx/test/std/utilities/time/time.clock/time.clock.system/from_time_t.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.clock/time.clock.system/from_time_t.pass.cpp
@@ -15,9 +15,11 @@
 #include <chrono>
 #include <ctime>
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::system_clock C;
     C::time_point t1 = C::from_time_t(C::to_time_t(C::now()));
     ((void)t1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.clock/time.clock.system/local_time.types.pass.cpp b/libcxx/test/std/utilities/time/time.clock/time.clock.system/local_time.types.pass.cpp
index 398cdb9d760bc237f28a706182df8b3e3c14435a..5802166c876d51c3da1ccd24c8968af9ed942a5f 100644
--- a/libcxx/test/std/utilities/time/time.clock/time.clock.system/local_time.types.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.clock/time.clock.system/local_time.types.pass.cpp
@@ -26,7 +26,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using local_t = std::chrono::local_t;
     using year    = std::chrono::year;
@@ -61,4 +61,6 @@ int main()
     ASSERT_SAME_TYPE(decltype(s0.time_since_epoch()), seconds);
     assert( s0.time_since_epoch().count() == 0);
     assert( s1.time_since_epoch().count() == 946684800L);
+
+    return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.clock/time.clock.system/now.pass.cpp b/libcxx/test/std/utilities/time/time.clock/time.clock.system/now.pass.cpp
index 00a163685f6404ae10a203fc5d8b65b226b7c35e..9d74541f989608ea32e36ed4ac58c0f94789025f 100644
--- a/libcxx/test/std/utilities/time/time.clock/time.clock.system/now.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.clock/time.clock.system/now.pass.cpp
@@ -15,11 +15,13 @@
 #include <chrono>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::system_clock C;
     C::time_point t1 = C::now();
     assert(t1.time_since_epoch().count() != 0);
     assert(C::time_point::min() < t1);
     assert(C::time_point::max() > t1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.clock/time.clock.system/rep_signed.pass.cpp b/libcxx/test/std/utilities/time/time.clock/time.clock.system/rep_signed.pass.cpp
index cae8375d873243b38bf3607b58a6d41d8a5e8b67..967af52e11d23511b31a0658c11046ccf85bf1fb 100644
--- a/libcxx/test/std/utilities/time/time.clock/time.clock.system/rep_signed.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.clock/time.clock.system/rep_signed.pass.cpp
@@ -15,8 +15,10 @@
 #include <chrono>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert(std::chrono::system_clock::duration::min() <
            std::chrono::system_clock::duration::zero());
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.clock/time.clock.system/sys.time.types.pass.cpp b/libcxx/test/std/utilities/time/time.clock/time.clock.system/sys.time.types.pass.cpp
index 516f54914fd443221661e0857625a3d88023e631..174fbe941442096b77c21d1e3705b0650f1581d9 100644
--- a/libcxx/test/std/utilities/time/time.clock/time.clock.system/sys.time.types.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.clock/time.clock.system/sys.time.types.pass.cpp
@@ -25,7 +25,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using system_clock = std::chrono::system_clock;
     using year         = std::chrono::year;
@@ -60,4 +60,6 @@ int main()
     ASSERT_SAME_TYPE(decltype(s0.time_since_epoch()), seconds);
     assert( s0.time_since_epoch().count() == 0);
     assert( s1.time_since_epoch().count() == 946684800L);
+
+    return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.clock/time.clock.system/to_time_t.pass.cpp b/libcxx/test/std/utilities/time/time.clock/time.clock.system/to_time_t.pass.cpp
index 0819a7b547f63934484fd487d5ac855f4d187f6d..86b37bb6bd1bda1a85e6b68a0770607c6702adbf 100644
--- a/libcxx/test/std/utilities/time/time.clock/time.clock.system/to_time_t.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.clock/time.clock.system/to_time_t.pass.cpp
@@ -15,9 +15,11 @@
 #include <chrono>
 #include <ctime>
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::system_clock C;
     std::time_t t1 = C::to_time_t(C::now());
     ((void)t1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/default_ratio.pass.cpp b/libcxx/test/std/utilities/time/time.duration/default_ratio.pass.cpp
index 92c015eef3253e6fa6d527125a1d619d65a0e9ef..08870488c16a5850e248977cfffb87dc94fb6a00 100644
--- a/libcxx/test/std/utilities/time/time.duration/default_ratio.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/default_ratio.pass.cpp
@@ -18,8 +18,10 @@
 #include <chrono>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::chrono::duration<int, std::ratio<1> >,
                    std::chrono::duration<int> >::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/duration.fail.cpp b/libcxx/test/std/utilities/time/time.duration/duration.fail.cpp
index 94e239c1f7cef01a6dc58b15891e906a1e4a2e4f..02029c02bbecaacc126cf32ae45cedb368110f78 100644
--- a/libcxx/test/std/utilities/time/time.duration/duration.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/duration.fail.cpp
@@ -15,8 +15,10 @@
 
 #include <chrono>
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::duration<std::chrono::milliseconds> D;
     D d;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/positive_num.fail.cpp b/libcxx/test/std/utilities/time/time.duration/positive_num.fail.cpp
index 6e78f7765618330ce20458fe04b5d6aa596ca978..737576205cf075dec8dd011a70a15cd01e7001fc 100644
--- a/libcxx/test/std/utilities/time/time.duration/positive_num.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/positive_num.fail.cpp
@@ -14,8 +14,10 @@
 
 #include <chrono>
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::duration<int, std::ratio<5, -1> > D;
     D d;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/ratio.fail.cpp b/libcxx/test/std/utilities/time/time.duration/ratio.fail.cpp
index 21873788a36c9c2dbd6482993d341b5e21e118e1..20298b772cb5cfac2a807df356dc893ee6085947 100644
--- a/libcxx/test/std/utilities/time/time.duration/ratio.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/ratio.fail.cpp
@@ -22,8 +22,10 @@ public:
     static const int den = D;
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::duration<int, Ratio<1> > D;
     D d;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.alg/abs.fail.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.alg/abs.fail.cpp
index 6331dc95a9a317f923b46885c700c0a2df18fddd..8d807c7a9b39573138ccc03d3dac97d377b9891f 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.alg/abs.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.alg/abs.fail.cpp
@@ -20,7 +20,9 @@
 
 typedef std::chrono::duration<unsigned> unsigned_secs;
 
-int main()
+int main(int, char**)
 {
     std::chrono::abs(unsigned_secs(0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.alg/abs.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.alg/abs.pass.cpp
index 5cb52ba76232b27668881bdab91c9aa389f714da..06f9a7c7f036a6e3048f72ada0137b15d70f78b8 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.alg/abs.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.alg/abs.pass.cpp
@@ -30,7 +30,7 @@ test(const Duration& f, const Duration& d)
     }
 }
 
-int main()
+int main(int, char**)
 {
 //  7290000ms is 2 hours, 1 minute, and 30 seconds
     test(std::chrono::milliseconds( 7290000), std::chrono::milliseconds( 7290000));
@@ -46,4 +46,6 @@ int main()
     constexpr std::chrono::hours h2 = std::chrono::abs(std::chrono::hours(3));
     static_assert(h2.count() == 3, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_++.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_++.pass.cpp
index 9d6566a082ca239decda64e77ac9076a3ed60d6b..d0e47b7fa8d5e23bc51ef8d04bc62574515a98a6 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_++.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_++.pass.cpp
@@ -25,7 +25,7 @@ constexpr bool test_constexpr()
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
     std::chrono::hours h(3);
@@ -37,4 +37,6 @@ int main()
 #if TEST_STD_VER > 14
     static_assert(test_constexpr(), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_++int.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_++int.pass.cpp
index 78beffe2617a9308a739c4fbe7bcc4c0ace3d2c5..084819af3ce8f8eac80330cdb47e0003eb954f9a 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_++int.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_++int.pass.cpp
@@ -26,7 +26,7 @@ constexpr bool test_constexpr()
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
     std::chrono::hours h1(3);
@@ -38,4 +38,6 @@ int main()
 #if TEST_STD_VER > 14
     static_assert(test_constexpr(), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_+.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_+.pass.cpp
index 0b8f49fc38f65743f2cd0030365d49b5b8631f6d..a9d136f792ae61d5fcce5b976ec717d76248437e 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_+.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_+.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     const std::chrono::minutes m(3);
@@ -42,4 +42,6 @@ int main()
     static_assert( (std::is_same< decltype(zero+one), D1>::value), "");
     static_assert( (std::is_same< decltype(+one),     D1>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_+=.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_+=.pass.cpp
index 0e907b573b22e9f0db9048d9524db0365423b3a9..4247f2d56893ad36b1850a1bfb3fd070b50c88e0 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_+=.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_+=.pass.cpp
@@ -28,7 +28,7 @@ constexpr bool test_constexpr()
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
     std::chrono::seconds s(3);
@@ -41,4 +41,6 @@ int main()
 #if TEST_STD_VER > 14
     static_assert(test_constexpr(), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_--.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_--.pass.cpp
index c9f1278a37619b5d08df5e8ca630e93b2af9ebeb..cfdb7075b3732927d82b02ccdc82fc9be7b78c78 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_--.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_--.pass.cpp
@@ -25,7 +25,7 @@ constexpr bool test_constexpr()
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
     std::chrono::hours h(3);
@@ -37,4 +37,6 @@ int main()
 #if TEST_STD_VER > 14
     static_assert(test_constexpr(), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_--int.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_--int.pass.cpp
index 5abecee1648d2092044e4dbbf8c5b13dd2922bcb..4afb86e0caf24a68befd825b243b23622fff7260 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_--int.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_--int.pass.cpp
@@ -27,7 +27,7 @@ constexpr bool test_constexpr()
 #endif
 
 
-int main()
+int main(int, char**)
 {
     {
     std::chrono::hours h1(3);
@@ -39,4 +39,6 @@ int main()
 #if TEST_STD_VER > 14
     static_assert(test_constexpr(), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_-.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_-.pass.cpp
index f7ab6d2e299fb215920d55c4d2060e1332a447cc..fe065ff5f997ca249eec1b5da937dc6b4553a3b8 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_-.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_-.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     const std::chrono::minutes m(3);
@@ -43,4 +43,6 @@ int main()
     static_assert( (std::is_same< decltype(-one),     D1>::value), "");
     static_assert( (std::is_same< decltype(+one),     D1>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_-=.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_-=.pass.cpp
index 1752d5257b806ff7e775a767089c790afaae617c..b457619e15492926173bbc1e75738543e5947819 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_-=.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_-=.pass.cpp
@@ -28,7 +28,7 @@ constexpr bool test_constexpr()
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
     std::chrono::seconds s(3);
@@ -41,4 +41,6 @@ int main()
 #if TEST_STD_VER > 14
     static_assert(test_constexpr(), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_divide=.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_divide=.pass.cpp
index 4f79398f73b8a29b8a933958955aa27c2c74d19b..753ea5a8bc1eb73eabb553e9e6fbd9e930307f6f 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_divide=.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_divide=.pass.cpp
@@ -26,7 +26,7 @@ constexpr bool test_constexpr()
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
     std::chrono::nanoseconds ns(15);
@@ -37,4 +37,6 @@ int main()
 #if TEST_STD_VER > 14
     static_assert(test_constexpr(), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_mod=duration.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_mod=duration.pass.cpp
index 89b550d015c0dcf17a10f7f5e1bb30f707aa156f..649f4aa1a4ceffaf410626eb8dad4b512e79954b 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_mod=duration.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_mod=duration.pass.cpp
@@ -27,7 +27,7 @@ constexpr bool test_constexpr()
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
     std::chrono::microseconds us1(11);
@@ -41,4 +41,6 @@ int main()
 #if TEST_STD_VER > 14
     static_assert(test_constexpr(), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_mod=rep.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_mod=rep.pass.cpp
index 8ef16c7ff7c925f898e4bc8ea8e54afa7b0024d3..0eb73ee674f11b12d69021745e1c83dcd5f80427 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_mod=rep.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_mod=rep.pass.cpp
@@ -26,7 +26,7 @@ constexpr bool test_constexpr()
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
     std::chrono::microseconds us(11);
@@ -37,4 +37,6 @@ int main()
 #if TEST_STD_VER > 14
     static_assert(test_constexpr(), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_times=.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_times=.pass.cpp
index b4b76fb6f505603e5c102a995e23f0a4a8b7f32e..51c20c5076496f19c655aa7b41d1c039254b6b7a 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_times=.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_times=.pass.cpp
@@ -26,7 +26,7 @@ constexpr bool test_constexpr()
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
     std::chrono::nanoseconds ns(3);
@@ -37,4 +37,6 @@ int main()
 #if TEST_STD_VER > 14
     static_assert(test_constexpr(), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.cast/ceil.fail.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.cast/ceil.fail.cpp
index e557bc21fb561f6d67e90aae3e8a70f52d19239d..a9711f448c878451cc655846b29d9ea532e11ed0 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.cast/ceil.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.cast/ceil.fail.cpp
@@ -19,7 +19,9 @@
 
 #include <chrono>
 
-int main()
+int main(int, char**)
 {
     std::chrono::ceil<int>(std::chrono::milliseconds(3));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.cast/ceil.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.cast/ceil.pass.cpp
index b509182c41ea5974df4a5f761395e5b544d91080..a6e1982d044585cfe1c375e11086fdaf10a839fe 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.cast/ceil.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.cast/ceil.pass.cpp
@@ -32,7 +32,7 @@ test(const FromDuration& f, const ToDuration& d)
     }
 }
 
-int main()
+int main(int, char**)
 {
 //  7290000ms is 2 hours, 1 minute, and 30 seconds
     test(std::chrono::milliseconds( 7290000), std::chrono::hours( 3));
@@ -47,4 +47,6 @@ int main()
     constexpr std::chrono::hours h2 = std::chrono::ceil<std::chrono::hours>(std::chrono::milliseconds(-9000000));
     static_assert(h2.count() == -2, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.cast/duration_cast.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.cast/duration_cast.pass.cpp
index 5187d3d0e7cc2f1ddd7b6a473ecf8154bc5cf323..4151756764abf44d6e68e45b9775e325296a22ca 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.cast/duration_cast.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.cast/duration_cast.pass.cpp
@@ -32,7 +32,7 @@ test(const FromDuration& f, const ToDuration& d)
     }
 }
 
-int main()
+int main(int, char**)
 {
     test(std::chrono::milliseconds(7265000), std::chrono::hours(2));
     test(std::chrono::milliseconds(7265000), std::chrono::minutes(121));
@@ -50,4 +50,6 @@ int main()
     static_assert(h.count() == 2, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.cast/floor.fail.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.cast/floor.fail.cpp
index 62dd5a51d6064bd4ab7f33412adc6c7ffe6ae77e..c119a800cfaeeb70454c8cc3034162465febfdc6 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.cast/floor.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.cast/floor.fail.cpp
@@ -19,7 +19,9 @@
 
 #include <chrono>
 
-int main()
+int main(int, char**)
 {
     std::chrono::floor<int>(std::chrono::milliseconds(3));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.cast/floor.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.cast/floor.pass.cpp
index 29142bdcf3e2629b01b265fc3c07afdc0a3627e5..6783b1f67eda50e54f51f0e1151d3d952d236dae 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.cast/floor.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.cast/floor.pass.cpp
@@ -31,7 +31,7 @@ test(const FromDuration& f, const ToDuration& d)
     }
 }
 
-int main()
+int main(int, char**)
 {
 //  7290000ms is 2 hours, 1 minute, and 30 seconds
     test(std::chrono::milliseconds( 7290000), std::chrono::hours( 2));
@@ -46,4 +46,6 @@ int main()
     constexpr std::chrono::hours h2 = std::chrono::floor<std::chrono::hours>(std::chrono::milliseconds(-9000000));
     static_assert(h2.count() == -3, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.cast/round.fail.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.cast/round.fail.cpp
index aadfbfdc47eb33bff459675829549fc75abd4adb..93366b83618db2ef38c7e5d7dcd9cea0cfa2eb58 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.cast/round.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.cast/round.fail.cpp
@@ -19,7 +19,9 @@
 
 #include <chrono>
 
-int main()
+int main(int, char**)
 {
     std::chrono::round<int>(std::chrono::milliseconds(3));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.cast/round.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.cast/round.pass.cpp
index b0789b7917d79f1e870b86f7f18208f353df43af..ebd2e3194a4acdefd4e0a87aac33640e7beabc3a 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.cast/round.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.cast/round.pass.cpp
@@ -31,7 +31,7 @@ test(const FromDuration& f, const ToDuration& d)
     }
 }
 
-int main()
+int main(int, char**)
 {
 //  7290000ms is 2 hours, 1 minute, and 30 seconds
     test(std::chrono::milliseconds( 7290000), std::chrono::hours( 2));
@@ -46,4 +46,6 @@ int main()
     constexpr std::chrono::hours h2 = std::chrono::round<std::chrono::hours>(std::chrono::milliseconds(-9000000));
     static_assert(h2.count() == -2, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.cast/toduration.fail.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.cast/toduration.fail.cpp
index a46aa526bda8eca19ce20687b34d567e3d101790..0f52c36d86cae905494cce1d74cda18a2a070e94 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.cast/toduration.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.cast/toduration.fail.cpp
@@ -18,7 +18,9 @@
 
 #include <chrono>
 
-int main()
+int main(int, char**)
 {
     std::chrono::duration_cast<int>(std::chrono::milliseconds(3));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.comparisons/op_equal.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.comparisons/op_equal.pass.cpp
index 912d22fdf0eee53bffafac40d066fb36cd2b0e8d..c27b528017ec9e2ff9a3a5ee16366fcc676f3e37 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.comparisons/op_equal.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.comparisons/op_equal.pass.cpp
@@ -25,7 +25,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::chrono::seconds s1(3);
@@ -113,4 +113,6 @@ int main()
     static_assert(!(s1 != s2), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.comparisons/op_less.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.comparisons/op_less.pass.cpp
index 9eea6ceb3bde8186fbb41c2830462bfcd5c39985..de476357650c9356e6396f48d3cf0a6af798bc28 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.comparisons/op_less.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.comparisons/op_less.pass.cpp
@@ -35,7 +35,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::chrono::seconds s1(3);
@@ -151,4 +151,6 @@ int main()
     static_assert( (s1 >= s2), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.cons/convert_exact.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.cons/convert_exact.pass.cpp
index 0f6fb8d3590c863b9d098bfef85b40a79cdb48bc..4c0af92b23d0392f1e309af27104ea656e1473cc 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.cons/convert_exact.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.cons/convert_exact.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::chrono::milliseconds ms(1);
@@ -34,4 +34,6 @@ int main()
     static_assert(us.count() == 1000, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.cons/convert_float_to_int.fail.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.cons/convert_float_to_int.fail.cpp
index b35c01c40ec4d5aad2cd5c802887e29f683e3430..4311c1bde38315d7bca65a10b74bf26f1fcf075f 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.cons/convert_float_to_int.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.cons/convert_float_to_int.fail.cpp
@@ -17,8 +17,10 @@
 
 #include <chrono>
 
-int main()
+int main(int, char**)
 {
     std::chrono::duration<double> d;
     std::chrono::duration<int> i = d;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.cons/convert_inexact.fail.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.cons/convert_inexact.fail.cpp
index b66b2f3c601d6c0d4f5df61cb5e064544ae245a0..fb0b488f7d8dfbc453ed1c0082c1c1c0f8e682cb 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.cons/convert_inexact.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.cons/convert_inexact.fail.cpp
@@ -17,8 +17,10 @@
 
 #include <chrono>
 
-int main()
+int main(int, char**)
 {
     std::chrono::microseconds us(1);
     std::chrono::milliseconds ms = us;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.cons/convert_inexact.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.cons/convert_inexact.pass.cpp
index 5624327badc927c5b5e68e7957edda07aae95691..f72c69c7ef1abdfb248cb32cdf323dc30ede31c7 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.cons/convert_inexact.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.cons/convert_inexact.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::chrono::duration<double, std::micro> us(1);
@@ -34,4 +34,6 @@ int main()
     static_assert(ms.count() == 1./1000, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.cons/convert_int_to_float.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.cons/convert_int_to_float.pass.cpp
index a63471bc37dc781a3b1a2a9563aa1eee54179e04..fb127226a6c45b973f913f53461eeb3842beffe2 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.cons/convert_int_to_float.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.cons/convert_int_to_float.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::chrono::duration<int> i(3);
@@ -34,4 +34,6 @@ int main()
     static_assert(d.count() == 3000, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.cons/convert_overflow.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.cons/convert_overflow.pass.cpp
index 68484d1fb51f74aec2f35819b2a8a796d7229d1a..5b963f2b1f4cbeb1baa635ca25caccddbfa34529 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.cons/convert_overflow.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.cons/convert_overflow.pass.cpp
@@ -26,11 +26,13 @@ void f(std::chrono::seconds)
     called = true;
 }
 
-int main()
+int main(int, char**)
 {
     {
     std::chrono::duration<int, std::exa> r(1);
     f(r);
     assert(called);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.cons/default.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.cons/default.pass.cpp
index 9edcd46f902fcbf35796b97219f5d85dd2ead2bd..c598afa365109a950fe56ae51f9c6a3e09a851f5 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.cons/default.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.cons/default.pass.cpp
@@ -32,7 +32,9 @@ test()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test<std::chrono::duration<Rep> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.cons/rep.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.cons/rep.pass.cpp
index f89263bf9b09114665368343754260c4b50b20ee..d1a808ba154129d25d5213b90ee82172b56f63e5 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.cons/rep.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.cons/rep.pass.cpp
@@ -31,10 +31,12 @@ test(R r)
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test<std::chrono::duration<int> >(5);
     test<std::chrono::duration<int, std::ratio<3, 2> > >(5);
     test<std::chrono::duration<Rep, std::ratio<3, 2> > >(Rep(3));
     test<std::chrono::duration<double, std::ratio<2, 3> > >(5.5);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.cons/rep01.fail.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.cons/rep01.fail.cpp
index fc6f5700a6a98d31d03020180dcd720bac8db3a2..f1e60f5e54d3f91d5c243bccc7cc82647fa4f2ca 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.cons/rep01.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.cons/rep01.fail.cpp
@@ -19,7 +19,9 @@
 
 #include "../../rep.h"
 
-int main()
+int main(int, char**)
 {
     std::chrono::duration<int> d = 1;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.cons/rep02.fail.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.cons/rep02.fail.cpp
index bdbe7211b817ce80f7cc6c162b2d61badb5a03db..4a09325065caea861369fb9d01785c7c5139da93 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.cons/rep02.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.cons/rep02.fail.cpp
@@ -19,7 +19,9 @@
 
 #include "../../rep.h"
 
-int main()
+int main(int, char**)
 {
     std::chrono::duration<Rep> d(1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.cons/rep02.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.cons/rep02.pass.cpp
index 3ecb76135e1fa47d8a13f3d2bbd519d5ba23e548..1719b1302bafb00085a59c8633d3dd946d386e79 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.cons/rep02.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.cons/rep02.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     std::chrono::duration<double> d(5);
     assert(d.count() == 5);
@@ -28,4 +28,6 @@ int main()
     constexpr std::chrono::duration<double> d2(5);
     static_assert(d2.count() == 5, "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.cons/rep03.fail.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.cons/rep03.fail.cpp
index 831370994ee602964b4b10ac5537765d49967de6..6b4d0020379c0b8d0df1050d7d630dc03d24f962 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.cons/rep03.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.cons/rep03.fail.cpp
@@ -17,7 +17,9 @@
 
 #include <chrono>
 
-int main()
+int main(int, char**)
 {
     std::chrono::duration<int> d(1.);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.literals/literals.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.literals/literals.pass.cpp
index 13ad165b7bfc857b9e01bf7b981485f0d6d4b4a7..0d924f8f70bebfd91186d80574dbd2b9295d7ff6 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.literals/literals.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.literals/literals.pass.cpp
@@ -15,7 +15,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     using namespace std::literals::chrono_literals;
 
@@ -57,4 +57,6 @@ int main()
     auto ns2 = 645.ns;
     assert ( ns == ns2 );
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.literals/literals1.fail.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.literals/literals1.fail.cpp
index 025100c592847401bbfeeda17f580e917f57b1fb..97e29e8768286db4b06c11b99e007bdba640a363 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.literals/literals1.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.literals/literals1.fail.cpp
@@ -11,8 +11,10 @@
 #include <chrono>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::chrono::hours h  = 4h;  // should fail w/conversion operator not found
+
+  return 0;
 }
 
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.literals/literals1.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.literals/literals1.pass.cpp
index 9ca29086777e6f48d6f7ef52aa06e7bfb1c55ee2..2e5b7bbb87b6cc920d1963f3cd1f8c0ac1a695a7 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.literals/literals1.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.literals/literals1.pass.cpp
@@ -11,7 +11,7 @@
 #include <chrono>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     using namespace std::chrono;
 
@@ -67,4 +67,6 @@ int main()
     assert(November  == month(11));
     assert(December  == month(12));
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.literals/literals2.fail.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.literals/literals2.fail.cpp
index 5c38db52713d59d68c8bc5c707aa0929710126c0..dbc91559031e0e2c641f9c3efa2eb9ea6d883535 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.literals/literals2.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.literals/literals2.fail.cpp
@@ -11,9 +11,11 @@
 #include <chrono>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     using std::chrono::hours;
 
     hours foo  =  4h;  // should fail w/conversion operator not found
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.literals/literals2.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.literals/literals2.pass.cpp
index 4070910325491a686742acce0997e6506ad73b55..d0b8b33e4934c390b4f5f7a2934232023c0bc158 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.literals/literals2.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.literals/literals2.pass.cpp
@@ -13,7 +13,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     using namespace std::literals;
 
@@ -46,4 +46,6 @@ int main()
     assert ( ns == std::chrono::nanoseconds(645));
     auto ns2 = 645.ns;
     assert ( ns == ns2 );
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_+.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_+.pass.cpp
index 30aa62cd9d1d6bc740930a3ed0126dc6fd8ff8b3..ad381f0056584b7e7e0afaa7c3429d68889a955c 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_+.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_+.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::chrono::seconds s1(3);
@@ -71,4 +71,6 @@ int main()
     static_assert(r.count() == 75, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_-.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_-.pass.cpp
index cb0a53fdf54a9892c85ff6faece146ddf3b31a46..86ced3fbcbd2a2bcd1dd1e9be1dbd20a8236e75d 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_-.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_-.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::chrono::seconds s1(3);
@@ -72,4 +72,6 @@ int main()
     static_assert(r.count() == -15, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_divide_duration.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_divide_duration.pass.cpp
index 40f521bae01dea371eff708a23bb89cfeb268902..e4190fe338543f379c8ab01b40d43eb045c26364 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_divide_duration.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_divide_duration.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_macros.h"
 #include "truncate_fp.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::chrono::nanoseconds ns1(15);
@@ -65,4 +65,6 @@ int main()
     static_assert(s1 / s2 == 20./3, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_divide_rep.fail.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_divide_rep.fail.cpp
index 41c55fccaebe18c9085642ead818cc72ef81672f..327ff563567f36ffab6a5358512cd3bd1742d08b 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_divide_rep.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_divide_rep.fail.cpp
@@ -18,8 +18,10 @@
 
 #include "../../rep.h"
 
-int main()
+int main(int, char**)
 {
     std::chrono::duration<Rep> d(Rep(15));
     d = d / 5;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_divide_rep.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_divide_rep.pass.cpp
index 8718ad75730dad6365b6f3ab2cee651156baad17..94da11302bf72910700054a97db870d4308336eb 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_divide_rep.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_divide_rep.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::chrono::nanoseconds ns(15);
@@ -34,4 +34,6 @@ int main()
     static_assert(ns2.count() == 3, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_mod_duration.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_mod_duration.pass.cpp
index 7a2063ca54e9564cb047caac08ca8ef8d78d3135..e7007c1fe35aa5171c52bbeb908cbc526b77ec32 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_mod_duration.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_mod_duration.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::chrono::nanoseconds ns1(15);
@@ -60,4 +60,6 @@ int main()
     static_assert(r.count() == 24, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_mod_rep.fail.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_mod_rep.fail.cpp
index 3ee0578f805d65fc00c1133b5d130a2ee070056e..f2a5885aba62814f3d907fae670b121051a57aa5 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_mod_rep.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_mod_rep.fail.cpp
@@ -18,8 +18,10 @@
 
 #include "../../rep.h"
 
-int main()
+int main(int, char**)
 {
     std::chrono::duration<Rep> d(Rep(15));
     d = d % 5;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_mod_rep.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_mod_rep.pass.cpp
index 6d7e285d9b8ac012406d49af875714a76582eee8..754b9800a7d901b7196424f1918e9246ff8935b5 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_mod_rep.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_mod_rep.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::chrono::nanoseconds ns(15);
@@ -34,4 +34,6 @@ int main()
     static_assert(ns2.count() == 3, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_times_rep.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_times_rep.pass.cpp
index 19e33366f71cf59c18834a0979b3e4d2e2ce092c..c3e499638082fa5cad96b1478e6e8e62d8fc25eb 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_times_rep.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_times_rep.pass.cpp
@@ -25,7 +25,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::chrono::nanoseconds ns(3);
@@ -43,4 +43,6 @@ int main()
     static_assert(ns3.count() == 18, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_times_rep1.fail.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_times_rep1.fail.cpp
index 6ad3c7928a909463a5c982f671f16144721178d6..44a77cea18a6fa014927b99ce00756a19ed7da79 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_times_rep1.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_times_rep1.fail.cpp
@@ -22,8 +22,10 @@
 
 #include "../../rep.h"
 
-int main()
+int main(int, char**)
 {
     std::chrono::duration<Rep> d;
     d = d * 5;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_times_rep2.fail.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_times_rep2.fail.cpp
index 5cc717c5c04975d095e6647431106a919f78bab0..9ce82582cf3b9936ddaae90ffc7cbfa28a67f608 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_times_rep2.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.nonmember/op_times_rep2.fail.cpp
@@ -22,8 +22,10 @@
 
 #include "../../rep.h"
 
-int main()
+int main(int, char**)
 {
     std::chrono::duration<Rep> d;
     d = 5 * d;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.observer/tested_elsewhere.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.observer/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.observer/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.observer/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.special/max.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.special/max.pass.cpp
index c6f3f1e65478567c778f4e46eb27fb6bf57996b3..58de66a01583d397492b8aa2bd93e0172dad6b48 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.special/max.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.special/max.pass.cpp
@@ -40,8 +40,10 @@ void test()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test<std::chrono::duration<int> >();
     test<std::chrono::duration<Rep> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.special/min.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.special/min.pass.cpp
index b16e608dcc756999850be812198606b462ad936b..9b0113b2980de4d68c87881c0ac260465f18895b 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.special/min.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.special/min.pass.cpp
@@ -40,8 +40,10 @@ void test()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test<std::chrono::duration<int> >();
     test<std::chrono::duration<Rep> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.special/zero.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.special/zero.pass.cpp
index f3065c30542624a7fc5b8fd718cfc29733877492..34a05b5f0715f81f1596f47c0f71a9939bbb9f99 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.special/zero.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.special/zero.pass.cpp
@@ -39,8 +39,10 @@ void test()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test<std::chrono::duration<int> >();
     test<std::chrono::duration<Rep> >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.duration/types.pass.cpp b/libcxx/test/std/utilities/time/time.duration/types.pass.cpp
index 9e5abbc20a70764accfaead108da25dbf4b63257..250e532859e9d6879e4f03c89cdee3d662a40eac 100644
--- a/libcxx/test/std/utilities/time/time.duration/types.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/types.pass.cpp
@@ -18,9 +18,11 @@
 #include <chrono>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::duration<long, std::ratio<3, 2> > D;
     static_assert((std::is_same<D::rep, long>::value), "");
     static_assert((std::is_same<D::period, std::ratio<3, 2> >::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.point/default_duration.pass.cpp b/libcxx/test/std/utilities/time/time.point/default_duration.pass.cpp
index e645e2970c634b501b7a91e9bf34bf4e221111f5..8a58413a0aafdf67fd97f8d7e72cbbd09f7fb7eb 100644
--- a/libcxx/test/std/utilities/time/time.point/default_duration.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.point/default_duration.pass.cpp
@@ -18,8 +18,10 @@
 #include <chrono>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::chrono::system_clock::duration,
                    std::chrono::time_point<std::chrono::system_clock>::duration>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.point/duration.fail.cpp b/libcxx/test/std/utilities/time/time.point/duration.fail.cpp
index a4881acc931123be85a44a54d66740ba983c882b..6461eb3d96f5f7211a7830994d771e90a1000e36 100644
--- a/libcxx/test/std/utilities/time/time.point/duration.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.point/duration.fail.cpp
@@ -14,8 +14,10 @@
 
 #include <chrono>
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::time_point<std::chrono::system_clock, int> T;
     T t;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.point/time.point.arithmetic/op_+=.pass.cpp b/libcxx/test/std/utilities/time/time.point/time.point.arithmetic/op_+=.pass.cpp
index 999071b72c69bbabf6a736cc0d514bdec37802ce..002fffc3882a1ac588f2fd8396b11d3b884a866d 100644
--- a/libcxx/test/std/utilities/time/time.point/time.point.arithmetic/op_+=.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.point/time.point.arithmetic/op_+=.pass.cpp
@@ -29,7 +29,7 @@ constexpr bool constexpr_test()
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::chrono::system_clock Clock;
@@ -42,4 +42,6 @@ int main()
 #if TEST_STD_VER > 14
     static_assert(constexpr_test(), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.point/time.point.arithmetic/op_-=.pass.cpp b/libcxx/test/std/utilities/time/time.point/time.point.arithmetic/op_-=.pass.cpp
index 3d62cdedaac488872b79c971d698611ec3915180..2365d539ca77513213e0f8feefe6e74b41defd2f 100644
--- a/libcxx/test/std/utilities/time/time.point/time.point.arithmetic/op_-=.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.point/time.point.arithmetic/op_-=.pass.cpp
@@ -29,7 +29,7 @@ constexpr bool constexpr_test()
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::chrono::system_clock Clock;
@@ -42,4 +42,6 @@ int main()
 #if TEST_STD_VER > 14
     static_assert(constexpr_test(), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.point/time.point.cast/ceil.fail.cpp b/libcxx/test/std/utilities/time/time.point/time.point.cast/ceil.fail.cpp
index 4a90ec870cf55937b6c18b411d8b199426262158..fb82fdffe4d2a97872c5feebaa478e7b8c38a878 100644
--- a/libcxx/test/std/utilities/time/time.point/time.point.cast/ceil.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.point/time.point.cast/ceil.fail.cpp
@@ -19,7 +19,9 @@
 
 #include <chrono>
 
-int main()
+int main(int, char**)
 {
     std::chrono::ceil<int>(std::chrono::system_clock::now());
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.point/time.point.cast/ceil.pass.cpp b/libcxx/test/std/utilities/time/time.point/time.point.cast/ceil.pass.cpp
index efd2a3e592b457245c2a11cf20991a278fac138f..8dfd1bdaa38f8a8f2fa614b48c7020da9d70fb99 100644
--- a/libcxx/test/std/utilities/time/time.point/time.point.cast/ceil.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.point/time.point.cast/ceil.pass.cpp
@@ -49,7 +49,7 @@ void test_constexpr ()
 }
 
 
-int main()
+int main(int, char**)
 {
 //  7290000ms is 2 hours, 1 minute, and 30 seconds
     test(std::chrono::milliseconds( 7290000), std::chrono::hours( 3));
@@ -65,4 +65,6 @@ int main()
 
     test_constexpr<std::chrono::milliseconds, 9000000, std::chrono::seconds, 9000> ();
     test_constexpr<std::chrono::milliseconds,-9000000, std::chrono::seconds,-9000> ();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.point/time.point.cast/floor.fail.cpp b/libcxx/test/std/utilities/time/time.point/time.point.cast/floor.fail.cpp
index c5dfba6c4f175fb9261a9d0f00cc732f7a3c556b..12b1dec9fd50950be9826eb53b01965428c0d3b2 100644
--- a/libcxx/test/std/utilities/time/time.point/time.point.cast/floor.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.point/time.point.cast/floor.fail.cpp
@@ -19,7 +19,9 @@
 
 #include <chrono>
 
-int main()
+int main(int, char**)
 {
     std::chrono::floor<int>(std::chrono::system_clock::now());
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.point/time.point.cast/floor.pass.cpp b/libcxx/test/std/utilities/time/time.point/time.point.cast/floor.pass.cpp
index db2391d2518fb63529569975427bc6a766550e6c..d50fff4a1c88b6ce4531d8cca232b74aabe49960 100644
--- a/libcxx/test/std/utilities/time/time.point/time.point.cast/floor.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.point/time.point.cast/floor.pass.cpp
@@ -48,7 +48,7 @@ void test_constexpr ()
     }
 }
 
-int main()
+int main(int, char**)
 {
 //  7290000ms is 2 hours, 1 minute, and 30 seconds
     test(std::chrono::milliseconds( 7290000), std::chrono::hours( 2));
@@ -64,4 +64,6 @@ int main()
 
     test_constexpr<std::chrono::milliseconds, 9000000, std::chrono::seconds, 9000> ();
     test_constexpr<std::chrono::milliseconds,-9000000, std::chrono::seconds,-9000> ();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.point/time.point.cast/round.fail.cpp b/libcxx/test/std/utilities/time/time.point/time.point.cast/round.fail.cpp
index 6c6f9c5bf5c514d261afe713113a3fb6ad5cfff7..a5436c684040d1f9d928634a7cd503b53d9594b5 100644
--- a/libcxx/test/std/utilities/time/time.point/time.point.cast/round.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.point/time.point.cast/round.fail.cpp
@@ -19,7 +19,9 @@
 
 #include <chrono>
 
-int main()
+int main(int, char**)
 {
     std::chrono::round<int>(std::chrono::system_clock::now());
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.point/time.point.cast/round.pass.cpp b/libcxx/test/std/utilities/time/time.point/time.point.cast/round.pass.cpp
index e68e233969d14f35182cb829674b4fe74cc5cb5c..d8bb1b505b1484be35b43b8fd8b31c44db1e51d9 100644
--- a/libcxx/test/std/utilities/time/time.point/time.point.cast/round.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.point/time.point.cast/round.pass.cpp
@@ -48,7 +48,7 @@ void test_constexpr ()
     }
 }
 
-int main()
+int main(int, char**)
 {
 //  7290000ms is 2 hours, 1 minute, and 30 seconds
     test(std::chrono::milliseconds( 7290000), std::chrono::hours( 2));
@@ -64,4 +64,6 @@ int main()
 
     test_constexpr<std::chrono::milliseconds, 9000000, std::chrono::seconds, 9000> ();
     test_constexpr<std::chrono::milliseconds,-9000000, std::chrono::seconds,-9000> ();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.point/time.point.cast/time_point_cast.pass.cpp b/libcxx/test/std/utilities/time/time.point/time.point.cast/time_point_cast.pass.cpp
index 5779ef9208ad335bb98aede02448804b75d7619e..90e6ccef666bbe0dff7dff204752ae9d187daf5e 100644
--- a/libcxx/test/std/utilities/time/time.point/time.point.cast/time_point_cast.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.point/time.point.cast/time_point_cast.pass.cpp
@@ -54,7 +54,7 @@ void test_constexpr ()
 
 #endif
 
-int main()
+int main(int, char**)
 {
     test(std::chrono::milliseconds(7265000), std::chrono::hours(2));
     test(std::chrono::milliseconds(7265000), std::chrono::minutes(121));
@@ -78,4 +78,6 @@ int main()
     test_constexpr<std::chrono::duration<int, std::ratio<2, 3>>, 9, T1, 10> ();
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.point/time.point.cast/toduration.fail.cpp b/libcxx/test/std/utilities/time/time.point/time.point.cast/toduration.fail.cpp
index 9e1f903b93f572820d1bd903818b9f37f30d570b..c16492f730a17d6499f2be81baca0a761086551c 100644
--- a/libcxx/test/std/utilities/time/time.point/time.point.cast/toduration.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.point/time.point.cast/toduration.fail.cpp
@@ -18,10 +18,12 @@
 
 #include <chrono>
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::system_clock Clock;
     typedef std::chrono::time_point<Clock, std::chrono::milliseconds> FromTimePoint;
     typedef std::chrono::time_point<Clock, std::chrono::minutes> ToTimePoint;
     std::chrono::time_point_cast<ToTimePoint>(FromTimePoint(std::chrono::milliseconds(3)));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.point/time.point.comparisons/op_equal.fail.cpp b/libcxx/test/std/utilities/time/time.point/time.point.comparisons/op_equal.fail.cpp
index e2b3508e00008f7d6c08ecf817981bfc83101e42..2b5795026b34ac2717dc99166ef270e1a6f81a38 100644
--- a/libcxx/test/std/utilities/time/time.point/time.point.comparisons/op_equal.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.point/time.point.comparisons/op_equal.fail.cpp
@@ -24,7 +24,7 @@
 
 #include "../../clock.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::system_clock Clock1;
     typedef Clock                     Clock2;
@@ -36,4 +36,6 @@ int main()
     T1 t1(Duration1(3));
     T2 t2(Duration2(3000));
     t1 == t2;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.point/time.point.comparisons/op_equal.pass.cpp b/libcxx/test/std/utilities/time/time.point/time.point.comparisons/op_equal.pass.cpp
index cc2ef33376309efa7cc806c6a09df7dc5c80af6c..f110ec5d4064cad165a571005539ef0a4344635d 100644
--- a/libcxx/test/std/utilities/time/time.point/time.point.comparisons/op_equal.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.point/time.point.comparisons/op_equal.pass.cpp
@@ -23,7 +23,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::system_clock Clock;
     typedef std::chrono::milliseconds Duration1;
@@ -82,4 +82,6 @@ int main()
     static_assert( (t1 != t2), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.point/time.point.comparisons/op_less.fail.cpp b/libcxx/test/std/utilities/time/time.point/time.point.comparisons/op_less.fail.cpp
index 04f7639d605b54ebf5395966ff806604dd6ba539..3d158ea890fc707b6d10a315d786593b51bbec80 100644
--- a/libcxx/test/std/utilities/time/time.point/time.point.comparisons/op_less.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.point/time.point.comparisons/op_less.fail.cpp
@@ -32,7 +32,7 @@
 
 #include "../../clock.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::system_clock Clock1;
     typedef Clock                     Clock2;
@@ -44,4 +44,6 @@ int main()
     T1 t1(Duration1(3));
     T2 t2(Duration2(3000));
     t1 < t2;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.point/time.point.comparisons/op_less.pass.cpp b/libcxx/test/std/utilities/time/time.point/time.point.comparisons/op_less.pass.cpp
index 57d24d08d02364447bf13104acb6875fa709f6e8..3b4aa6abecf9a2c54936effc93b287f22fe3f0fe 100644
--- a/libcxx/test/std/utilities/time/time.point/time.point.comparisons/op_less.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.point/time.point.comparisons/op_less.pass.cpp
@@ -31,7 +31,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::system_clock Clock;
     typedef std::chrono::milliseconds Duration1;
@@ -106,4 +106,6 @@ int main()
     static_assert(!(t1 >= t2), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.point/time.point.cons/convert.fail.cpp b/libcxx/test/std/utilities/time/time.point/time.point.cons/convert.fail.cpp
index a68d4b0f304c19875095866f43f4bff91acaee48..2e601179a7da8aaf145b6f086824bb414b6539d9 100644
--- a/libcxx/test/std/utilities/time/time.point/time.point.cons/convert.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.point/time.point.cons/convert.fail.cpp
@@ -17,7 +17,7 @@
 
 #include <chrono>
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::system_clock Clock;
     typedef std::chrono::milliseconds Duration1;
@@ -26,4 +26,6 @@ int main()
     std::chrono::time_point<Clock, Duration2> t2(Duration2(3));
     std::chrono::time_point<Clock, Duration1> t1 = t2;
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.point/time.point.cons/convert.pass.cpp b/libcxx/test/std/utilities/time/time.point/time.point.cons/convert.pass.cpp
index 91bcebb1a91c316364634355554709e470f733a7..f9b35c957385838c825ba1260da136bc5888792e 100644
--- a/libcxx/test/std/utilities/time/time.point/time.point.cons/convert.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.point/time.point.cons/convert.pass.cpp
@@ -18,7 +18,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::system_clock Clock;
     typedef std::chrono::microseconds Duration1;
@@ -35,4 +35,6 @@ int main()
     static_assert(t1.time_since_epoch() == Duration1(3000), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.point/time.point.cons/default.pass.cpp b/libcxx/test/std/utilities/time/time.point/time.point.cons/default.pass.cpp
index 2deb8ae298cd955b7a9be25ec340f9f1ea2065d7..b40113999a573200b29493fad78d67d24a945f43 100644
--- a/libcxx/test/std/utilities/time/time.point/time.point.cons/default.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.point/time.point.cons/default.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "../../rep.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::system_clock Clock;
     typedef std::chrono::duration<Rep, std::milli> Duration;
@@ -32,4 +32,6 @@ int main()
     static_assert(t.time_since_epoch() == Duration::zero(), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.point/time.point.cons/duration.fail.cpp b/libcxx/test/std/utilities/time/time.point/time.point.cons/duration.fail.cpp
index 4a42eef3057127f550d55848a73cc19468401612..b28116236d051ed6a5498459af74d17093c73d2d 100644
--- a/libcxx/test/std/utilities/time/time.point/time.point.cons/duration.fail.cpp
+++ b/libcxx/test/std/utilities/time/time.point/time.point.cons/duration.fail.cpp
@@ -16,9 +16,11 @@
 
 #include <chrono>
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::system_clock Clock;
     typedef std::chrono::milliseconds Duration;
     std::chrono::time_point<Clock, Duration> t = Duration(3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.point/time.point.cons/duration.pass.cpp b/libcxx/test/std/utilities/time/time.point/time.point.cons/duration.pass.cpp
index 0830eea91198e154d28d2edc4168f0d1b9485815..078c6641e76df6f996eb14068bea49e4e9b5306a 100644
--- a/libcxx/test/std/utilities/time/time.point/time.point.cons/duration.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.point/time.point.cons/duration.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::system_clock Clock;
     typedef std::chrono::milliseconds Duration;
@@ -39,4 +39,6 @@ int main()
     static_assert(t.time_since_epoch() == Duration(3000), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.point/time.point.nonmember/op_+.pass.cpp b/libcxx/test/std/utilities/time/time.point/time.point.nonmember/op_+.pass.cpp
index df6c691572e491b0351cbadd6ae935a1faa1c35c..7d78f7f43290a919b0f4cc7d1b60b6df39494838 100644
--- a/libcxx/test/std/utilities/time/time.point/time.point.nonmember/op_+.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.point/time.point.nonmember/op_+.pass.cpp
@@ -23,7 +23,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::system_clock Clock;
     typedef std::chrono::milliseconds Duration1;
@@ -44,4 +44,6 @@ int main()
     static_assert(t3.time_since_epoch() == Duration2(3006), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.point/time.point.nonmember/op_-duration.pass.cpp b/libcxx/test/std/utilities/time/time.point/time.point.nonmember/op_-duration.pass.cpp
index 876d42d560d027d0fe85b26dc66457a62cb66dce..6fe8769695b1a273f0d5beb5c77f3abc09f4eb68 100644
--- a/libcxx/test/std/utilities/time/time.point/time.point.nonmember/op_-duration.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.point/time.point.nonmember/op_-duration.pass.cpp
@@ -30,7 +30,7 @@ void test2739()  // LWG2739
     assert(t1 < t0);
 }
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::system_clock Clock;
     typedef std::chrono::milliseconds Duration1;
@@ -49,4 +49,6 @@ int main()
 #endif
     test2739<int32_t>();
     test2739<uint32_t>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.point/time.point.nonmember/op_-time_point.pass.cpp b/libcxx/test/std/utilities/time/time.point/time.point.nonmember/op_-time_point.pass.cpp
index 851869d4d0d5b36ed2ae0fd28bcc4d7c5f133295..22e4520f360047825f8abe9b2e4593a9b2d6c34b 100644
--- a/libcxx/test/std/utilities/time/time.point/time.point.nonmember/op_-time_point.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.point/time.point.nonmember/op_-time_point.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::system_clock Clock;
     typedef std::chrono::milliseconds Duration1;
@@ -36,4 +36,6 @@ int main()
     static_assert((t1 - t2) == Duration2(2995), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.point/time.point.observer/tested_elsewhere.pass.cpp b/libcxx/test/std/utilities/time/time.point/time.point.observer/tested_elsewhere.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/time/time.point/time.point.observer/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.point/time.point.observer/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.point/time.point.special/max.pass.cpp b/libcxx/test/std/utilities/time/time.point/time.point.special/max.pass.cpp
index c8f2d41be9750b4762620f329204d30f6f92371c..e7826b1a61011e1787b9693602ed635b41d728a4 100644
--- a/libcxx/test/std/utilities/time/time.point/time.point.special/max.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.point/time.point.special/max.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::system_clock Clock;
     typedef std::chrono::milliseconds Duration;
@@ -27,4 +27,6 @@ int main()
     ASSERT_NOEXCEPT(       TP::max());
 #endif
     assert(TP::max() == TP(Duration::max()));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.point/time.point.special/min.pass.cpp b/libcxx/test/std/utilities/time/time.point/time.point.special/min.pass.cpp
index 1cac230624fa6d495b7ee847b92d4607de35801d..fae3339b03d845c478dc79898b37b2d2abb7c91a 100644
--- a/libcxx/test/std/utilities/time/time.point/time.point.special/min.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.point/time.point.special/min.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::system_clock Clock;
     typedef std::chrono::milliseconds Duration;
@@ -27,4 +27,6 @@ int main()
     ASSERT_NOEXCEPT(       TP::max());
 #endif
     assert(TP::min() == TP(Duration::min()));
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.traits/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/time/time.traits/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/time/time.traits/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.traits/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.traits/time.traits.duration_values/max.pass.cpp b/libcxx/test/std/utilities/time/time.traits/time.traits.duration_values/max.pass.cpp
index f44a7964f02b16590e00454cc28f180960816822..8d244c77346b8c9ff2194122a4d208b05fc73b3e 100644
--- a/libcxx/test/std/utilities/time/time.traits/time.traits.duration_values/max.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.traits/time.traits.duration_values/max.pass.cpp
@@ -17,7 +17,7 @@
 #include "test_macros.h"
 #include "../../rep.h"
 
-int main()
+int main(int, char**)
 {
     assert(std::chrono::duration_values<int>::max() ==
            std::numeric_limits<int>::max());
@@ -42,4 +42,6 @@ int main()
     ASSERT_NOEXCEPT(std::chrono::duration_values<double>::max());
     ASSERT_NOEXCEPT(std::chrono::duration_values<Rep>::max());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.traits/time.traits.duration_values/min.pass.cpp b/libcxx/test/std/utilities/time/time.traits/time.traits.duration_values/min.pass.cpp
index c64746d9fc7b661f70a75edea428794763f31f1e..4ff03c62286821d9f30234754fed266b93c18dfd 100644
--- a/libcxx/test/std/utilities/time/time.traits/time.traits.duration_values/min.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.traits/time.traits.duration_values/min.pass.cpp
@@ -17,7 +17,7 @@
 #include "test_macros.h"
 #include "../../rep.h"
 
-int main()
+int main(int, char**)
 {
     assert(std::chrono::duration_values<int>::min() ==
            std::numeric_limits<int>::lowest());
@@ -42,4 +42,6 @@ int main()
     ASSERT_NOEXCEPT(std::chrono::duration_values<double>::min());
     ASSERT_NOEXCEPT(std::chrono::duration_values<Rep>::min());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.traits/time.traits.duration_values/zero.pass.cpp b/libcxx/test/std/utilities/time/time.traits/time.traits.duration_values/zero.pass.cpp
index 6eec47ce3b0eacc6edd585215734714e21dd2939..d9de07b414e98aa8d09f78b8131deaf68b0b8c84 100644
--- a/libcxx/test/std/utilities/time/time.traits/time.traits.duration_values/zero.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.traits/time.traits.duration_values/zero.pass.cpp
@@ -16,7 +16,7 @@
 #include "test_macros.h"
 #include "../../rep.h"
 
-int main()
+int main(int, char**)
 {
     assert(std::chrono::duration_values<int>::zero() == 0);
     assert(std::chrono::duration_values<Rep>::zero() == 0);
@@ -31,4 +31,6 @@ int main()
     ASSERT_NOEXCEPT(std::chrono::duration_values<int>::zero());
     ASSERT_NOEXCEPT(std::chrono::duration_values<Rep>::zero());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.traits/time.traits.is_fp/treat_as_floating_point.pass.cpp b/libcxx/test/std/utilities/time/time.traits/time.traits.is_fp/treat_as_floating_point.pass.cpp
index cf588f5c0af576075be92397d483a845512ba497..9db3d96d26d60446cc90f2bd75da8b7f67c230f5 100644
--- a/libcxx/test/std/utilities/time/time.traits/time.traits.is_fp/treat_as_floating_point.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.traits/time.traits.is_fp/treat_as_floating_point.pass.cpp
@@ -29,7 +29,7 @@ test()
 
 struct A {};
 
-int main()
+int main(int, char**)
 {
     test<int>();
     test<unsigned>();
@@ -39,4 +39,6 @@ int main()
     test<double>();
     test<long double>();
     test<A>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.traits/time.traits.specializations/duration.pass.cpp b/libcxx/test/std/utilities/time/time.traits/time.traits.specializations/duration.pass.cpp
index 39afe6a5f53a05c812d4182575d0332745e5fd2f..3dde5404727057106fbb094338e08bb0f3764744 100644
--- a/libcxx/test/std/utilities/time/time.traits/time.traits.specializations/duration.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.traits/time.traits.specializations/duration.pass.cpp
@@ -24,7 +24,7 @@ test()
     static_assert((std::is_same<Dc, De>::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     test<std::chrono::duration<int, std::ratio<1, 100> >,
          std::chrono::duration<long, std::ratio<1, 1000> >,
@@ -38,4 +38,6 @@ int main()
     test<std::chrono::duration<double, std::ratio<21, 1> >,
          std::chrono::duration<short, std::ratio<15, 1> >,
          std::chrono::duration<double, std::ratio<3, 1> > >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/time.traits/time.traits.specializations/time_point.pass.cpp b/libcxx/test/std/utilities/time/time.traits/time.traits.specializations/time_point.pass.cpp
index bf880fcd2b70dc3644202758b60ff18beed878c9..d73bb8ae6fdaff25f07b923b130d8a9e3fdb9e48 100644
--- a/libcxx/test/std/utilities/time/time.traits/time.traits.specializations/time_point.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.traits/time.traits.specializations/time_point.pass.cpp
@@ -28,7 +28,7 @@ test()
     static_assert((std::is_same<Tc, Te>::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     test<std::chrono::duration<int, std::ratio<1, 100> >,
          std::chrono::duration<long, std::ratio<1, 1000> >,
@@ -42,4 +42,6 @@ int main()
     test<std::chrono::duration<double, std::ratio<21, 1> >,
          std::chrono::duration<short, std::ratio<15, 1> >,
          std::chrono::duration<double, std::ratio<3, 1> > >();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/weeks.pass.cpp b/libcxx/test/std/utilities/time/weeks.pass.cpp
index 2231c69550c049ec9e5b5c6e45cace4ae90354b5..5a0cf3417f51f40e3bf2f4e1746c1b12306b6c1a 100644
--- a/libcxx/test/std/utilities/time/weeks.pass.cpp
+++ b/libcxx/test/std/utilities/time/weeks.pass.cpp
@@ -15,7 +15,7 @@
 #include <type_traits>
 #include <limits>
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::weeks D;
     typedef D::rep Rep;
@@ -24,4 +24,6 @@ int main()
     static_assert(std::is_integral<Rep>::value, "");
     static_assert(std::numeric_limits<Rep>::digits >= 22, "");
     static_assert(std::is_same_v<Period, std::ratio_multiply<std::ratio<7>, std::chrono::days::period>>, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/time/years.pass.cpp b/libcxx/test/std/utilities/time/years.pass.cpp
index c2229caee6384d3e37b8bf5ebe54a969e139960e..5016369268a48031afbfbd37525e6f3be27e82c3 100644
--- a/libcxx/test/std/utilities/time/years.pass.cpp
+++ b/libcxx/test/std/utilities/time/years.pass.cpp
@@ -15,7 +15,7 @@
 #include <type_traits>
 #include <limits>
 
-int main()
+int main(int, char**)
 {
     typedef std::chrono::years D;
     typedef D::rep Rep;
@@ -24,4 +24,6 @@ int main()
     static_assert(std::is_integral<Rep>::value, "");
     static_assert(std::numeric_limits<Rep>::digits >= 17, "");
     static_assert(std::is_same_v<Period, std::ratio_multiply<std::ratio<146097, 400>, std::chrono::days::period>>, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.general/ignore.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.general/ignore.pass.cpp
index d216c19fc5404a6f20d3ef30891f7a55a31f79df..5d0409a7ca33eb51968b4767453472b269051561 100644
--- a/libcxx/test/std/utilities/tuple/tuple.general/ignore.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.general/ignore.pass.cpp
@@ -39,7 +39,7 @@ constexpr bool test_ignore_constexpr()
     return true;
 }
 
-int main() {
+int main(int, char**) {
     {
         constexpr auto& ignore_v = std::ignore;
         ((void)ignore_v);
@@ -50,4 +50,6 @@ int main() {
     {
         LIBCPP_STATIC_ASSERT(std::is_trivial<decltype(std::ignore)>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.general/tuple.smartptr.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.general/tuple.smartptr.pass.cpp
index 326d7bb589e20f7d95a82d72bab85ff5ea5f674a..d57e7ad1825a07e7503488b074cb551841619368 100644
--- a/libcxx/test/std/utilities/tuple/tuple.general/tuple.smartptr.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.general/tuple.smartptr.pass.cpp
@@ -15,7 +15,7 @@
 #include <tuple>
 #include <memory>
 
-int main () {
+int main(int, char**) {
     {
     std::tuple<std::unique_ptr<char>> up;
     std::tuple<std::shared_ptr<char>> sp;
@@ -29,4 +29,6 @@ int main () {
     // Smart pointers of type 'T[N]' are not tested here since they are not
     // supported by the standard nor by libc++'s implementation.
     // See https://reviews.llvm.org/D21320 for more information.
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/TupleFunction.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/TupleFunction.pass.cpp
index b9e6e111ca1db54b38c5a520004da7445dc0ac32..27f3d59349be24a4ce516c16394863c629b1197b 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/TupleFunction.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/TupleFunction.pass.cpp
@@ -25,11 +25,13 @@ struct X
     void operator()() {}
 };
 
-int main()
+int main(int, char**)
 {
     X x;
     std::function<void()> f(x);
+
+  return 0;
 }
 #else
-int main () {}
+int main(int, char**) { return 0; }
 #endif
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.apply/apply.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.apply/apply.pass.cpp
index 2daef09fb08d1c710399712b386fb36d1d0b3a35..52e94cc0b61b08a80c35e7d38230bce28d6a0802 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.apply/apply.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.apply/apply.pass.cpp
@@ -265,9 +265,11 @@ void test_return_type()
     test<13, int const volatile *>();
 }
 
-int main() {
+int main(int, char**) {
     test_constexpr_evaluation();
     test_call_quals_and_arg_types();
     test_return_type();
     test_noexcept();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.apply/apply_extended_types.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.apply/apply_extended_types.pass.cpp
index 978c923ef0c87266eb2bfbd5b62f3b4d2432c092..851a535eb49c52d801db7220cee883a2f230f9d6 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.apply/apply_extended_types.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.apply/apply_extended_types.pass.cpp
@@ -360,7 +360,7 @@ void test_ext_int_2()
     }
 }
 
-int main()
+int main(int, char**)
 {
     {
         test_ext_int_0<
@@ -422,4 +422,6 @@ int main()
           , std::tuple<A_base_2, int, int>, std::tuple<A_base_2 const, int, int>
           >();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.apply/apply_large_arity.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.apply/apply_large_arity.pass.cpp
index 138f074b243cdf31cf1453d72bb5dcb02b1c8d93..004a5d46435c4d0fbd6d56d8f96f1c50f524e49e 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.apply/apply_large_arity.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.apply/apply_large_arity.pass.cpp
@@ -129,7 +129,7 @@ void test_one()
     }
 }
 
-int main()
+int main(int, char**)
 {
     // Instantiate with 1-5 arguments.
     test_all<1>();
@@ -140,4 +140,6 @@ int main()
 
     // Stress test with 256
     test_one<256>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.apply/make_from_tuple.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.apply/make_from_tuple.pass.cpp
index 6afd8882512fd1e69cc05f4a0d34f79fdc64b100..53574ee1d8063cec855ffdc37453c1701ee0f2a8 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.apply/make_from_tuple.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.apply/make_from_tuple.pass.cpp
@@ -205,9 +205,11 @@ void test_noexcept() {
     }
 }
 
-int main()
+int main(int, char**)
 {
     test_constexpr_construction();
     test_perfect_forwarding();
     test_noexcept();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/const_pair.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/const_pair.pass.cpp
index bf4a8cc0dbb70e02bf54c5435d33866649e8ec03..9353add370fb4f1a67acf0c6e865aad901cb145b 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/const_pair.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/const_pair.pass.cpp
@@ -19,7 +19,7 @@
 #include <utility>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<long, char> T0;
@@ -30,4 +30,6 @@ int main()
         assert(std::get<0>(t1) == 2);
         assert(std::get<1>(t1) == short('a'));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/convert_copy.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/convert_copy.pass.cpp
index e21118a2f55d4b157a5190a8d5e54d80cba5cefb..8b9447c99001973092410eb1069b6a841279e84a 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/convert_copy.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/convert_copy.pass.cpp
@@ -32,7 +32,7 @@ struct D
     explicit D(int i = 0) : B(i) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::tuple<long> T0;
@@ -85,4 +85,6 @@ int main()
         assert(std::get<0>(t) == 43);
         assert(&std::get<0>(t) == &x);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/convert_move.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/convert_move.pass.cpp
index 95b1e2769de2b927520dd79f2d5984eb63f53545..71855a309c59609123758fe2c71ce7088b6b1516 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/convert_move.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/convert_move.pass.cpp
@@ -43,7 +43,7 @@ struct E {
   }
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::tuple<long> T0;
@@ -106,4 +106,6 @@ int main()
         assert(std::get<0>(t) == 43);
         assert(&std::get<0>(t) == &x);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/copy.fail.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/copy.fail.cpp
index 167d442b726fda00fe4e8e0cd03fc53bface1d66..c3fa6495ff7af9575d1a2f81f7a7edb005d2c244 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/copy.fail.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/copy.fail.cpp
@@ -19,7 +19,7 @@
 
 #include "MoveOnly.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::tuple<MoveOnly> T;
@@ -27,4 +27,6 @@ int main()
         T t;
         t = t0;
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/copy.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/copy.pass.cpp
index 5162c40533dcc279201428a7ba5a0e4260861058..f6ff1041e5c0a2a93d1d781d479524f690b8dc35 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/copy.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/copy.pass.cpp
@@ -35,7 +35,7 @@ struct MoveAssignable {
   MoveAssignable& operator=(MoveAssignable&&) = default;
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::tuple<> T;
@@ -100,4 +100,6 @@ int main()
         using T = std::tuple<int, MoveAssignable>;
         static_assert(!std::is_copy_assignable<T>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/move.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/move.pass.cpp
index 4545cf4df2bee29268fb1266f9bfa12c4949546d..575c3b1dfad6ef925401e14f89a39df2102385b0 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/move.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/move.pass.cpp
@@ -48,7 +48,7 @@ int CountAssign::copied = 0;
 int CountAssign::moved = 0;
 
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::tuple<> T;
@@ -122,4 +122,6 @@ int main()
         assert(CountAssign::copied == 1);
         assert(CountAssign::moved == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/move_pair.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/move_pair.pass.cpp
index 2dec9fffae5318b72e9f361ff1f8fb1c514b7469..9681a238a9d8751137a49601207412a5f9bf5404 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/move_pair.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/move_pair.pass.cpp
@@ -35,7 +35,7 @@ struct D
     explicit D(int i) : B(i) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<long, std::unique_ptr<D>> T0;
@@ -46,4 +46,6 @@ int main()
         assert(std::get<0>(t1) == 2);
         assert(std::get<1>(t1)->id_ == 3);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/tuple_array_template_depth.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/tuple_array_template_depth.pass.cpp
index 5e31090c9d59f0f5578f34f1dc99190e00aef399..5796e8dbe08008c409a3a1d30dd3fffa86826fdd 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/tuple_array_template_depth.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/tuple_array_template_depth.pass.cpp
@@ -25,9 +25,11 @@
 typedef std::array<char, 1256> array_t;
 typedef std::tuple<array_t> tuple_t;
 
-int main()
+int main(int, char**)
 {
     array_t arr;
     tuple_t tup;
     tup = arr;
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/PR20855_tuple_ref_binding_diagnostics.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/PR20855_tuple_ref_binding_diagnostics.pass.cpp
index b6e444c659ff2d386582b6d075f2adf18402d903..973aa93df3cc034b9e737305232138f5fa2c98a0 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/PR20855_tuple_ref_binding_diagnostics.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/PR20855_tuple_ref_binding_diagnostics.pass.cpp
@@ -131,7 +131,9 @@ void allocator_tests() {
 }
 
 
-int main() {
+int main(int, char**) {
   compile_tests();
   allocator_tests();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/PR22806_constrain_tuple_like_ctor.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/PR22806_constrain_tuple_like_ctor.pass.cpp
index 79064fb09c462f85f872444483a528773b07317f..1e1b0846cc28f7f7e0c39ac19eabdcbbcf532726 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/PR22806_constrain_tuple_like_ctor.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/PR22806_constrain_tuple_like_ctor.pass.cpp
@@ -78,7 +78,7 @@ struct ConvertibleFromInt {
   ConvertibleFromInt(int) : state(FromInt) {}
 };
 
-int main()
+int main(int, char**)
 {
     // Test for the creation of dangling references when a tuple is used to
     // store a reference to another tuple as its only element.
@@ -174,4 +174,6 @@ int main()
         std::tuple<VT> t2 = {t1};
         assert(std::get<0>(t2).state == VT::FromInt);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/PR23256_constrain_UTypes_ctor.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/PR23256_constrain_UTypes_ctor.pass.cpp
index 8992f7b820546b909cfb5a1eb8390bf794a29623..919d88e46a3e1c7d5f98ea6ebf86d63cc367ae3b 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/PR23256_constrain_UTypes_ctor.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/PR23256_constrain_UTypes_ctor.pass.cpp
@@ -57,7 +57,7 @@ struct ExplicitUnconstrainedCtor {
 
 };
 
-int main() {
+int main(int, char**) {
     typedef UnconstrainedCtor A;
     typedef ExplicitUnconstrainedCtor ExplicitA;
     {
@@ -94,4 +94,6 @@ int main() {
         std::tuple<ExplicitA&&> t2(std::forward_as_tuple(ExplicitA{}));
         ((void)t2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/PR27684_contains_ref_to_incomplete_type.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/PR27684_contains_ref_to_incomplete_type.pass.cpp
index 9f8658aa6420cb70c56e50b7e219d16e4b462ed1..1493f4f81609a9644dff4f6cb55c51f6be612e36 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/PR27684_contains_ref_to_incomplete_type.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/PR27684_contains_ref_to_incomplete_type.pass.cpp
@@ -29,7 +29,7 @@ extern IncompleteType inc2;
 IncompleteType const& cinc1 = inc1;
 IncompleteType const& cinc2 = inc2;
 
-int main() {
+int main(int, char**) {
     using IT = IncompleteType;
     { // try calling tuple(Tp const&...)
         using Tup = std::tuple<const IT&, const IT&>;
@@ -43,6 +43,8 @@ int main() {
         assert(&std::get<0>(t) == &inc1);
         assert(&std::get<1>(t) == &inc2);
     }
+
+  return 0;
 }
 
 struct IncompleteType {};
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/PR31384.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/PR31384.pass.cpp
index b0dd392f171bd2a52239c37685f850952048ac41..6c44f7027eedd93d7fbbf37879aa669915b93909 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/PR31384.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/PR31384.pass.cpp
@@ -44,7 +44,7 @@ struct ExplicitDerived : std::tuple<T> {
   explicit operator std::tuple<U>() && { ++count; return {}; }
 };
 
-int main() {
+int main(int, char**) {
   {
     std::tuple<Explicit> foo = Derived<int>{42}; ((void)foo);
     assert(count == 1);
@@ -84,4 +84,6 @@ int main() {
   }
   count = 0;
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/UTypes.fail.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/UTypes.fail.cpp
index 3a0e0f888e94ecc9bf7aba862e2ed7ab7bf45742..3b9d0beead9974a3f15fe7fca22a1cacfd5e76b2 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/UTypes.fail.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/UTypes.fail.cpp
@@ -42,9 +42,11 @@ public:
     bool operator< (const MoveOnly& x) const {return data_ <  x.data_;}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::tuple<MoveOnly> t = 1;
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/UTypes.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/UTypes.pass.cpp
index f43e6d8bcedba8df94f3c5e9551cd47772ef8b35..916255c967ac447129fab4103ed5cdbe9e96217e 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/UTypes.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/UTypes.pass.cpp
@@ -102,7 +102,7 @@ void test_default_constructible_extension_sfinae()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::tuple<MoveOnly> t(MoveOnly(0));
@@ -156,4 +156,6 @@ int main()
     // Check that SFINAE is properly applied with the default reduced arity
     // constructor extensions.
     test_default_constructible_extension_sfinae();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc.pass.cpp
index e4ed476900294edd329f8ad38002b95dbfff0654..c5f52a92846c5ba24fab939f18b94ce292dd8b7c 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc.pass.cpp
@@ -39,7 +39,7 @@ struct NonDefaultConstructible {
 
 struct DerivedFromAllocArgT : std::allocator_arg_t {};
 
-int main()
+int main(int, char**)
 {
     {
         std::tuple<> t(std::allocator_arg, A1<int>());
@@ -105,4 +105,6 @@ int main()
         std::tuple<T, T> t2(42, 42);
         (void)t2;
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_UTypes.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_UTypes.pass.cpp
index 99155823b3afc02187e2758e500137caee36142a..57e2f1b41887e8f3b74bde16fd275a6893a33fc9 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_UTypes.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_UTypes.pass.cpp
@@ -77,7 +77,7 @@ struct Explicit {
   explicit Explicit(int x) : value(x) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::tuple<Explicit> t{std::allocator_arg, std::allocator<void>{}, 42};
@@ -148,4 +148,6 @@ int main()
     // ensure that the "reduced-arity-initialization" extension is not offered
     // for these constructors.
     test_uses_allocator_sfinae_evaluation();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_const_Types.fail.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_const_Types.fail.cpp
index 1759ba4f3c4b8da6e588ed2f6ca35ae92bca438c..76f99e1978ddf122158fab20db4a90823ecabc2f 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_const_Types.fail.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_const_Types.fail.cpp
@@ -35,8 +35,10 @@ std::tuple<ExplicitCopy> non_const_explicity_copy_test() {
     return {std::allocator_arg, std::allocator<void>{}, e};
     // expected-error@-1 {{chosen constructor is explicit in copy-initialization}}
 }
-int main()
+int main(int, char**)
 {
     const_explicit_copy_test();
     non_const_explicity_copy_test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_const_Types.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_const_Types.pass.cpp
index 10647a49d14b2c4752064c7e8aa31c58ffc9c490..3b5b27f7b15090faf6060f66502140c0e1c27784 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_const_Types.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_const_Types.pass.cpp
@@ -40,7 +40,7 @@ std::tuple<ImplicitCopy> testImplicitCopy2() {
     return {std::allocator_arg, std::allocator<void>{}, i};
 }
 
-int main()
+int main(int, char**)
 {
     {
         // check that the literal '0' can implicitly initialize a stored pointer.
@@ -94,4 +94,6 @@ int main()
         assert(!alloc_last::allocator_constructed);
         assert(std::get<2>(t) == alloc_last(3));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_const_pair.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_const_pair.pass.cpp
index baafee879f9e5d0a8641df8b5747a651efe32287..a7cffa72db6e865b1dd66ae5c03204fc6cf1dc0d 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_const_pair.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_const_pair.pass.cpp
@@ -23,7 +23,7 @@
 #include "../alloc_first.h"
 #include "../alloc_last.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<long, int> T0;
@@ -55,4 +55,6 @@ int main()
         assert(std::get<0>(t1) == 2);
         assert(std::get<1>(t1) == 3);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_convert_copy.fail.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_convert_copy.fail.cpp
index 8d0482859a0cce98f34a0a55978209ac527365b4..ca9518d6b2bc9d6f20a43e11842c50c99ae4b7bd 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_convert_copy.fail.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_convert_copy.fail.cpp
@@ -36,7 +36,9 @@ std::tuple<ExplicitCopy> non_const_explicit_copy_test() {
     // expected-error@-1 {{chosen constructor is explicit in copy-initialization}}
 }
 
-int main()
+int main(int, char**)
 {
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_convert_copy.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_convert_copy.pass.cpp
index bcece6098302bd3ef8f7e2f48c1395e7bd8d45a6..083e15797f6459a4234aa74633820f58cb0951db 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_convert_copy.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_convert_copy.pass.cpp
@@ -33,7 +33,7 @@ struct Implicit {
   Implicit(int x) : value(x) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::tuple<long> T0;
@@ -86,4 +86,6 @@ int main()
         std::tuple<Implicit> t2 = {std::allocator_arg, std::allocator<void>{}, t1};
         assert(std::get<0>(t2).value == 42);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_convert_move.fail.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_convert_move.fail.cpp
index ed485c901073b5d363df0c07ba268a4b3c3eebf4..7a2a5ffff5de2510d61f24f59b6983547db77730 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_convert_move.fail.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_convert_move.fail.cpp
@@ -29,7 +29,9 @@ std::tuple<ExplicitCopy> explicit_move_test() {
     // expected-error@-1 {{chosen constructor is explicit in copy-initialization}}
 }
 
-int main()
+int main(int, char**)
 {
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_convert_move.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_convert_move.pass.cpp
index e86ec8aea926692bcd2ada1602e32a462fe3d3c6..1f33ef2fc6e3abf0900e1e13c4d15dec28398d0f 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_convert_move.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_convert_move.pass.cpp
@@ -49,7 +49,7 @@ struct Implicit {
   Implicit(int x) : value(x) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::tuple<int> T0;
@@ -100,4 +100,6 @@ int main()
         std::tuple<Implicit> t2 = {std::allocator_arg, std::allocator<void>{}, std::move(t1)};
         assert(std::get<0>(t2).value == 42);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_copy.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_copy.pass.cpp
index 19829a967bb795e5580970a6cefa5ef57a34ad0d..1db842b8d91f05ee38b439f277d6d7557e5418f8 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_copy.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_copy.pass.cpp
@@ -22,7 +22,7 @@
 #include "../alloc_first.h"
 #include "../alloc_last.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::tuple<> T;
@@ -77,4 +77,6 @@ int main()
         assert(std::get<2>(t) == 3);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_move.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_move.pass.cpp
index c77484de54b37d0cdacbc1546f6d60c0ccb1e34a..fc25a4fc6a4bbf5c0fc9785e5762ae7ab59b1a36 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_move.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_move.pass.cpp
@@ -23,7 +23,7 @@
 #include "../alloc_first.h"
 #include "../alloc_last.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::tuple<> T;
@@ -76,4 +76,6 @@ int main()
         assert(std::get<2>(t) == 3);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_move_pair.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_move_pair.pass.cpp
index 3da2d8a466daf794de89ca3974f37a4d893555e8..e45702d88b78af9245dff8074e3fa09dddb6973d 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_move_pair.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/alloc_move_pair.pass.cpp
@@ -39,7 +39,7 @@ struct D
     explicit D(int i) : B(i) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<int, std::unique_ptr<D>> T0;
@@ -51,4 +51,6 @@ int main()
         assert(std::get<0>(t1) == 2);
         assert(std::get<1>(t1)->id_ == 3);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/const_Types.fail.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/const_Types.fail.cpp
index 2a405c1a4af554e4d4a3c0b0cbe5691aa988796a..bb7c55735055835d3b47e632df4af508c7aeb6c2 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/const_Types.fail.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/const_Types.fail.cpp
@@ -42,6 +42,8 @@ std::tuple<ExplicitCopy> const_explicit_copy_no_brace() {
     // expected-error@-1 {{no viable conversion}}
 }
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/const_Types.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/const_Types.pass.cpp
index 955a83a6e880ef9057ecac83b44897d43cee5ba4..d4c29c93c379e4f1635411fc18a1d89cb836ef52 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/const_Types.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/const_Types.pass.cpp
@@ -76,7 +76,7 @@ std::tuple<ImplicitCopy> testImplicitCopy3() {
     return i;
 }
 
-int main()
+int main(int, char**)
 {
     {
         // check that the literal '0' can implicitly initialize a stored pointer.
@@ -159,4 +159,6 @@ int main()
         assert(std::get<3>(t) == 0.0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/const_Types2.fail.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/const_Types2.fail.cpp
index 35e82277f8ddff71586ff54bed70dcf71eceaf02..8804c27b8a23b360d0397756fb3c255f72a03b08 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/const_Types2.fail.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/const_Types2.fail.cpp
@@ -18,9 +18,11 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::tuple<int, char*, std::string, double&> t(2, nullptr, "text");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/const_pair.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/const_pair.pass.cpp
index 0fd29b22fd7388e250f50c490839362f7e46dfae..bbe51e392541423063615b2de68501d66d8444ab 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/const_pair.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/const_pair.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<long, char> T0;
@@ -42,4 +42,6 @@ int main()
         static_assert(std::get<1>(t1) == short('a'), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/convert_copy.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/convert_copy.pass.cpp
index 98d002b80424fe5e28db6d84e3d6a2ee8b1e9ec4..41f73328ab7b0dffc373d72ca59817a607a14781 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/convert_copy.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/convert_copy.pass.cpp
@@ -64,7 +64,7 @@ struct C
 
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::tuple<long> T0;
@@ -136,4 +136,6 @@ int main()
         std::tuple<Implicit> t2 = t1;
         assert(std::get<0>(t2).value == 42);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/convert_move.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/convert_move.pass.cpp
index 79332841eb86bbe02899122af3582988d8406fb3..071f13cf9136b1583ca7bf95e5073faf0e52ef08 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/convert_move.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/convert_move.pass.cpp
@@ -44,7 +44,7 @@ struct D
     explicit D(int i) : B(i) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::tuple<long> T0;
@@ -100,4 +100,6 @@ int main()
         std::tuple<Implicit> t2 = std::move(t1);
         assert(std::get<0>(t2).value == 42);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/copy.fail.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/copy.fail.cpp
index f82dc6b1ff2bedd2effaa2aa5510b7462737d2b8..7eeb65a8fdd515bc17f97f5315e9c7f8e5a0fb2a 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/copy.fail.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/copy.fail.cpp
@@ -19,11 +19,13 @@
 
 #include "MoveOnly.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::tuple<MoveOnly> T;
         T t0(MoveOnly(2));
         T t = t0;
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/copy.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/copy.pass.cpp
index 7c581cb771406e91c6cc51bad4519222902ee9c9..0127813040070fbce51589e2510fa6a66d99d6f6 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/copy.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/copy.pass.cpp
@@ -22,7 +22,7 @@
 
 struct Empty {};
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::tuple<> T;
@@ -66,4 +66,6 @@ int main()
         ((void)e); // Prevent unused warning
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/default.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/default.pass.cpp
index 15bcde7e973289dd31e757f49b49d2d052cb9686..ae296f73945c0a860ee6c86ab7443142aff70854 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/default.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/default.pass.cpp
@@ -44,7 +44,7 @@ struct IllFormedDefault {
     int value;
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::tuple<> t;
@@ -106,4 +106,6 @@ int main()
         IllFormedDefault v(0);
         std::tuple<IllFormedDefault> t(v);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/dtor.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/dtor.pass.cpp
index 1d4779aae36981c3bd47624cc60cb05caeb1c478..80b09b8718082d6a5519ab6615505bdf8f495841 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/dtor.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/dtor.pass.cpp
@@ -23,7 +23,7 @@
 #include <cassert>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
   static_assert(std::is_trivially_destructible<
       std::tuple<> >::value, "");
@@ -35,4 +35,6 @@ int main()
       std::tuple<std::string> >::value, "");
   static_assert(!std::is_trivially_destructible<
       std::tuple<int, std::string> >::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/implicit_deduction_guides.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/implicit_deduction_guides.pass.cpp
index ea393abafe440de133133612b28df1891b632ded..3ff089a0b311d9f53aed6b6c5d942cd4af45dc49 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/implicit_deduction_guides.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/implicit_deduction_guides.pass.cpp
@@ -149,7 +149,9 @@ void test_empty_specialization()
   }
 }
 
-int main() {
+int main(int, char**) {
   test_primary_template();
   test_empty_specialization();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/move.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/move.pass.cpp
index 98a12a972f8768903dc29139af4e5c05cf968406..977dc4c326419c9b7c3fb9a924925a56273b08af 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/move.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/move.pass.cpp
@@ -80,7 +80,7 @@ void test_sfinae() {
     }
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::tuple<> T;
@@ -121,4 +121,6 @@ int main()
         test_sfinae<move_only_ebo>();
         test_sfinae<move_only_large>();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/move_pair.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/move_pair.pass.cpp
index 3953ee150a222d3223d4130bb68f93565a68d5bc..635be614b9a4215bbec0c7bbb0045fccbb16e01e 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/move_pair.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/move_pair.pass.cpp
@@ -34,7 +34,7 @@ struct D
     explicit D(int i) : B(i) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<long, std::unique_ptr<D>> T0;
@@ -44,4 +44,6 @@ int main()
         assert(std::get<0>(t1) == 2);
         assert(std::get<1>(t1)->id_ == 3);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/test_lazy_sfinae.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/test_lazy_sfinae.pass.cpp
index 2486851564371ffe4d56decac70c330b2fccec5c..bdbe4fc4b44d210b2cfbfe79cea1a483908fc471 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/test_lazy_sfinae.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/test_lazy_sfinae.pass.cpp
@@ -95,7 +95,9 @@ void test_const_Types_lazy_sfinae()
     assert(std::get<0>(t).value == 42);
 }
 
-int main() {
+int main(int, char**) {
     test_tuple_like_lazy_sfinae();
     test_const_Types_lazy_sfinae();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/tuple_array_template_depth.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/tuple_array_template_depth.pass.cpp
index b84dba37899ade1a206cb336d0b966c9399ec426..2f9447f2a7d44d8b10cfea8618272d02bef5a9b3 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/tuple_array_template_depth.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.cnstr/tuple_array_template_depth.pass.cpp
@@ -28,8 +28,10 @@
 typedef std::array<char, 1256> array_t;
 typedef std::tuple<array_t> tuple_t;
 
-int main()
+int main(int, char**)
 {
     array_t arr;
     tuple_t tup(arr);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.creation/forward_as_tuple.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.creation/forward_as_tuple.pass.cpp
index 5a7940da65692fac505a52d9cb0da936a094fed2..8dc1e48f8675e30e1df9e7ddb62976305149131c 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.creation/forward_as_tuple.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.creation/forward_as_tuple.pass.cpp
@@ -64,7 +64,7 @@ test3(const Tuple&)
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         test0(std::forward_as_tuple());
@@ -84,4 +84,6 @@ int main()
         static_assert ( test3 (std::forward_as_tuple(i, c)) == 2, "" );
 #endif
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.creation/make_tuple.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.creation/make_tuple.pass.cpp
index 3f0dae093f067720c3ab81a5250cec2fc65c8749..444e978b01e5dacc1af0b892c3914c21d59ca1f2 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.creation/make_tuple.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.creation/make_tuple.pass.cpp
@@ -21,7 +21,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         int i = 0;
@@ -50,4 +50,6 @@ int main()
         static_assert (d1 == 3.14, "" );
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.creation/tie.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.creation/tie.pass.cpp
index f703ef2c849ca44d50d8b6e433fa9b161604990d..53ccc23b97c6cf703c824c214175ce39103434e4 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.creation/tie.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.creation/tie.pass.cpp
@@ -39,7 +39,7 @@ constexpr bool test_tie_constexpr() {
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         int i = 0;
@@ -60,4 +60,6 @@ int main()
         static_assert(test_tie_constexpr(), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.creation/tuple_cat.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.creation/tuple_cat.pass.cpp
index 927fc2ab891ada0c4ad54fc188467b16c79e0828..40efbd1b80149c7637fa008be2d4586ab1d011a5 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.creation/tuple_cat.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.creation/tuple_cat.pass.cpp
@@ -23,7 +23,7 @@
 #include "test_macros.h"
 #include "MoveOnly.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::tuple<> t = std::tuple_cat();
@@ -238,4 +238,6 @@ int main()
         );
         assert(t2 == std::make_tuple(std::make_tuple(1), std::make_tuple(2)));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/get_const.fail.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/get_const.fail.cpp
index 4c0b5a6b460c1bf9967b80db65fada78414ef919..650303ff7b296642ba5b422a5ad2abbd10b105a7 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/get_const.fail.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/get_const.fail.cpp
@@ -20,7 +20,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::tuple<double&, std::string, int> T;
@@ -37,4 +37,6 @@ int main()
 
         std::get<1>(t) = "four";
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/get_const.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/get_const.pass.cpp
index 5ca0bd8e9633b7142b9a1094dec881cc13ad436a..a280c500ba58b5828ea2746258b81fd0234220f2 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/get_const.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/get_const.pass.cpp
@@ -24,7 +24,7 @@
 
 struct Empty {};
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::tuple<int> T;
@@ -64,4 +64,6 @@ int main()
         assert(std::get<2>(t) == 5);
         assert(d == 2.5);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/get_const_rv.fail.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/get_const_rv.fail.cpp
index 373d84bad99a047630a11ef32e0b0023c2eb54cd..cf0e88246d37d4511f9066f1ac4ff6110f141da7 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/get_const_rv.fail.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/get_const_rv.fail.cpp
@@ -23,11 +23,13 @@ template <class T> void cref(T const&&) = delete;
 
 std::tuple<int> const tup4() { return std::make_tuple(4); }
 
-int main()
+int main(int, char**)
 {
     // LWG2485: tuple should not open a hole in the type system, get() should
     // imitate [expr.ref]'s rules for accessing data members
     {
         cref(std::get<0>(tup4()));  // expected-error {{call to deleted function 'cref'}}
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/get_const_rv.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/get_const_rv.pass.cpp
index 4c2654cd7354a4bcc3191fafae0996fec61c4d97..5801d5a5e65e0310fa493080779d6aa6636f8631 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/get_const_rv.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/get_const_rv.pass.cpp
@@ -24,7 +24,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::tuple<int> T;
@@ -76,4 +76,6 @@ int main()
     static_assert(std::get<1>(std::move(t)) == 5, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/get_non_const.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/get_non_const.pass.cpp
index 3708e5cb0ca7bb383328c1a67f87dc95b4e01198..3cbf01b25f86a856b3400ef03387600a63dd5fa7 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/get_non_const.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/get_non_const.pass.cpp
@@ -36,7 +36,7 @@ struct S {
 constexpr std::tuple<int, int> getP () { return { 3, 4 }; }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::tuple<int> T;
@@ -81,4 +81,6 @@ int main()
     }
 #endif
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/get_rv.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/get_rv.pass.cpp
index 114672b7c7a5f721500f7b088213653e4278840d..ae968403b015139fd8b307c55e8a2a29033c5651 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/get_rv.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/get_rv.pass.cpp
@@ -21,7 +21,7 @@
 #include <memory>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::tuple<std::unique_ptr<int> > T;
@@ -29,4 +29,6 @@ int main()
         std::unique_ptr<int> p = std::get<0>(std::move(t));
         assert(*p == 3);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/tuple.by.type.fail.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/tuple.by.type.fail.cpp
index f85c8098f7db12f31b1e057c4df6c294f7e5ba70..51bf1d550cd05d4e39f42c938e55ebd4f4eb3fa3 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/tuple.by.type.fail.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/tuple.by.type.fail.cpp
@@ -31,8 +31,10 @@ void test_bad_return_type() {
     upint p = std::get<upint>(t); // expected-error{{deleted copy constructor}}
 }
 
-int main()
+int main(int, char**)
 {
     test_bad_index();
     test_bad_return_type();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/tuple.by.type.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/tuple.by.type.pass.cpp
index 9df8ce381a7c40eee78c03fd4beccecb493d63a3..7dd4e8f10adb6492928bf47a1bed96a3bd6c13d8 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/tuple.by.type.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/tuple.by.type.pass.cpp
@@ -17,7 +17,7 @@
 
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::complex<float> cf;
     {
@@ -90,4 +90,6 @@ int main()
     static_assert(std::get<int>(std::move(t)) == 1, "");
     static_assert(std::get<const int>(std::move(t)) == 2, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple.include.array.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple.include.array.pass.cpp
index e56f86a1ccaf530e46ac8e45df4cedc3be05fabb..a97e60ca7799c8aeef3cd15583c71333b23d5a40 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple.include.array.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple.include.array.pass.cpp
@@ -40,7 +40,7 @@ void test()
     static_assert((std::is_same<typename std::tuple_element<idx, const volatile T>::type, const volatile U>::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     test<std::array<int, 5>, 5, int, 0>();
     test<std::array<int, 5>, 5, int, 1>();
@@ -48,4 +48,6 @@ int main()
     test<std::array<volatile int, 4>, 4, volatile int, 3>();
     test<std::array<char *, 3>, 3, char *, 1>();
     test<std::array<char *, 3>, 3, char *, 2>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple.include.utility.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple.include.utility.pass.cpp
index eb1704c943b749f0b9303f472af75db209c0656b..fdfb8b8b0a8feefc95ca5b75021de7175ee34d4f 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple.include.utility.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple.include.utility.pass.cpp
@@ -38,7 +38,7 @@ void test()
     static_assert((std::is_same<typename std::tuple_element<idx, const volatile T>::type, const volatile U>::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     test<std::pair<int, int>, 2, int, 0>();
     test<std::pair<int, int>, 2, int, 1>();
@@ -46,4 +46,6 @@ int main()
     test<std::pair<int, volatile int>, 2, volatile int, 1>();
     test<std::pair<char *, int>, 2, char *, 0>();
     test<std::pair<char *, int>, 2, int,    1>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_element.fail.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_element.fail.cpp
index a1c42921ba2882cd53be1ca9550c217532252575..24b735b7e685f23eeac397ff290c3249c35e4af0 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_element.fail.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_element.fail.cpp
@@ -22,7 +22,7 @@
 #include <tuple>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     using T =  std::tuple<int, long, void*>;
     using E1 = typename std::tuple_element<1, T &>::type; // expected-error{{undefined template}}
@@ -30,4 +30,6 @@ int main()
     using E3 = typename std::tuple_element<4, T const>::type;
         // expected-error@__tuple:* 2 {{static_assert failed}}
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_element.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_element.pass.cpp
index ecb6ea087ef088317c139c76c4560b9046e06ffb..5ad2b08220e2b283b788dad5a18a9d430e7aa850 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_element.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_element.pass.cpp
@@ -39,7 +39,7 @@ void test()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test<std::tuple<int>, 0, int>();
     test<std::tuple<char, int>, 0, char>();
@@ -47,4 +47,6 @@ int main()
     test<std::tuple<int*, char, int>, 0, int*>();
     test<std::tuple<int*, char, int>, 1, char>();
     test<std::tuple<int*, char, int>, 2, int>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size.fail.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size.fail.cpp
index aa20818393b339538bb77a8bcb89c6c8223b0661..9b065b3b9f6c8205412b26cdb3e81a3b7a9aa504 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size.fail.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size.fail.cpp
@@ -18,9 +18,11 @@
 
 #include <tuple>
 
-int main()
+int main(int, char**)
 {
     (void)std::tuple_size<std::tuple<> &>::value; // expected-error {{implicit instantiation of undefined template}}
     (void)std::tuple_size<int>::value; // expected-error {{implicit instantiation of undefined template}}
     (void)std::tuple_size<std::tuple<>*>::value; // expected-error {{implicit instantiation of undefined template}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size.pass.cpp
index 2a602b1ca260bc941a4d3a62455835615b6ea974..f27c7eb470a5b4ea50779b3fc07764d582e5a93f 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size.pass.cpp
@@ -32,10 +32,12 @@ void test()
                                    std::tuple_size<const volatile T> >::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     test<std::tuple<>, 0>();
     test<std::tuple<int>, 1>();
     test<std::tuple<char, int>, 2>();
     test<std::tuple<char, char*, int>, 3>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size_incomplete.fail.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size_incomplete.fail.cpp
index 3d092506828de37df1191790a1e86dd2cf143fab..83b773abf229fa6a9db7455fb22a2ebf2536f887 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size_incomplete.fail.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size_incomplete.fail.cpp
@@ -39,7 +39,7 @@ public:
 template <>
 struct std::tuple_size<Dummy3> {};
 
-int main()
+int main(int, char**)
 {
   // Test that tuple_size<const T> is not incomplete when tuple_size<T>::value
   // is well-formed but not a constant expression.
@@ -59,4 +59,6 @@ int main()
     // expected-error@__tuple:* 1 {{no member named 'value'}}
     (void)std::tuple_size<const Dummy3>::value; // expected-note {{here}}
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size_incomplete.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size_incomplete.pass.cpp
index 44e100c6d36c59d43469cba12a0ef375ba839532..32bad3317bcfa3d72b97447faade0d70a4601d29 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size_incomplete.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size_incomplete.pass.cpp
@@ -50,7 +50,7 @@ void test_incomplete() {
 }
 
 
-int main()
+int main(int, char**)
 {
   test_complete<std::tuple<> >();
   test_complete<std::tuple<int&> >();
@@ -63,4 +63,6 @@ int main()
   test_incomplete<int>();
   test_incomplete<std::tuple<int>&>();
   test_incomplete<Dummy2>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size_structured_bindings.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size_structured_bindings.pass.cpp
index f191f9f64d7871ae6a0145fd7d77c1c9d7bdd6a0..00f7ff2697266932e5037887ed15ff4b4e87e58e 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size_structured_bindings.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size_structured_bindings.pass.cpp
@@ -139,11 +139,13 @@ void test_after_tuple_size_specialization() {
   assert(p == -1);
 }
 
-int main() {
+int main(int, char**) {
   test_decomp_user_type();
   test_decomp_tuple();
   test_decomp_pair();
   test_decomp_array();
   test_before_tuple_size_specialization();
   test_after_tuple_size_specialization();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size_v.fail.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size_v.fail.cpp
index 820cb0443f8fc391617f531a3d9f4e09af30b49f..8bd3fbd579e1e9b6aa9eaf8239c38ae817000995 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size_v.fail.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size_v.fail.cpp
@@ -16,10 +16,12 @@
 
 #include <tuple>
 
-int main()
+int main(int, char**)
 {
     (void)std::tuple_size_v<std::tuple<> &>; // expected-note {{requested here}}
     (void)std::tuple_size_v<int>; // expected-note {{requested here}}
     (void)std::tuple_size_v<std::tuple<>*>; // expected-note {{requested here}}
     // expected-error@tuple:* 3 {{implicit instantiation of undefined template}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size_v.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size_v.pass.cpp
index b2b3e72b9be2eedbca8eeef6a85764dbfd91668f..bd01f49497c023a5a68035d194a5546035823746 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size_v.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size_v.pass.cpp
@@ -26,7 +26,7 @@ void test()
     static_assert(std::tuple_size_v<Tuple const volatile> == std::tuple_size<Tuple>::value, "");
 }
 
-int main()
+int main(int, char**)
 {
     test<std::tuple<>, 0>();
 
@@ -39,4 +39,6 @@ int main()
 
     test<std::tuple<int, int, int>, 3>();
     test<std::array<int, 3>, 3>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size_value_sfinae.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size_value_sfinae.pass.cpp
index 9c00418768f18e7ef906dd87a4947015cd6ba319..2efbfa50e15614995bf7069b348380e68f260bdf 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size_value_sfinae.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.helper/tuple_size_value_sfinae.pass.cpp
@@ -27,7 +27,7 @@ template <class T> constexpr bool has_value() { return has_value<T>(0); }
 
 struct Dummy {};
 
-int main() {
+int main(int, char**) {
   // Test that the ::value member does not exist
   static_assert(has_value<std::tuple<int> const>(), "");
   static_assert(has_value<std::pair<int, long> volatile>(), "");
@@ -35,4 +35,6 @@ int main() {
   static_assert(!has_value<const int>(), "");
   static_assert(!has_value<volatile void>(), "");
   static_assert(!has_value<const volatile std::tuple<int>&>(), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.rel/eq.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.rel/eq.pass.cpp
index 709f747c74444d65d1fb723f85f62d0e16fd601b..0302c839e7439da74b261414f331f6c2f5fe3d4d 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.rel/eq.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.rel/eq.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::tuple<> T1;
@@ -154,4 +154,6 @@ int main()
         static_assert(t1 != t2, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.rel/lt.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.rel/lt.pass.cpp
index 9f29c6c4a1b543b71c2d1b17adf190a45894a115..64ed9b4a90e73146113ac9ce319ee0e2629b985b 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.rel/lt.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.rel/lt.pass.cpp
@@ -34,7 +34,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::tuple<> T1;
@@ -208,4 +208,6 @@ int main()
         static_assert(!(t1 >= t2), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.special/non_member_swap.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.special/non_member_swap.pass.cpp
index 079977016b859b858311730fd6a949a86e733511..eee8f18196afbf7c62a9b4dfe107d3fedeb438c6 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.special/non_member_swap.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.special/non_member_swap.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "MoveOnly.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::tuple<> T;
@@ -58,4 +58,6 @@ int main()
         assert(std::get<1>(t1) == 1);
         assert(std::get<2>(t1) == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.swap/member_swap.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.swap/member_swap.pass.cpp
index 097f69b42eab004b4a46ea82a303d9ed4e6ba1db..951a88726098b9d40f3b63c41566c17f8da4e832 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.swap/member_swap.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.swap/member_swap.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "MoveOnly.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::tuple<> T;
@@ -57,4 +57,6 @@ int main()
         assert(std::get<1>(t1) == 1);
         assert(std::get<2>(t1) == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.traits/uses_allocator.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.traits/uses_allocator.pass.cpp
index 5e4722874af364abfb2db54351b16565266c2fa7..b04c491ede6f6535749f3a5a0c4c99178888cb35 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.traits/uses_allocator.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.traits/uses_allocator.pass.cpp
@@ -20,7 +20,7 @@
 
 struct A {};
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::tuple<> T;
@@ -42,4 +42,6 @@ int main()
         static_assert((std::is_base_of<std::true_type,
                                        std::uses_allocator<T, A>>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/type.index/type.index.hash/enabled_hash.pass.cpp b/libcxx/test/std/utilities/type.index/type.index.hash/enabled_hash.pass.cpp
index daa287e3e0114b16304bea440d75a37a006339e6..710b33878d9d6672b58feb10eb706c33d7e73664 100644
--- a/libcxx/test/std/utilities/type.index/type.index.hash/enabled_hash.pass.cpp
+++ b/libcxx/test/std/utilities/type.index/type.index.hash/enabled_hash.pass.cpp
@@ -17,6 +17,8 @@
 
 #include "poisoned_hash_helper.hpp"
 
-int main() {
+int main(int, char**) {
   test_library_hash_specializations_available();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/type.index/type.index.hash/hash.pass.cpp b/libcxx/test/std/utilities/type.index/type.index.hash/hash.pass.cpp
index 139847fdae5dc08db80235c9a2291e430f29bc4b..8192a9020f7083ca00198aa6ab2fd1992e67e813 100644
--- a/libcxx/test/std/utilities/type.index/type.index.hash/hash.pass.cpp
+++ b/libcxx/test/std/utilities/type.index/type.index.hash/hash.pass.cpp
@@ -21,7 +21,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::hash<std::type_index> H;
     static_assert((std::is_same<typename H::argument_type, std::type_index>::value), "" );
@@ -29,4 +29,6 @@ int main()
 
     std::type_index t1 = typeid(int);
     assert(std::hash<std::type_index>()(t1) == t1.hash_code());
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/type.index/type.index.members/ctor.pass.cpp b/libcxx/test/std/utilities/type.index/type.index.members/ctor.pass.cpp
index cafeebb0930cf0d647f2c5404b0ded2a4f206474..c133130f10e2ead9cc5550a211f9aea8f4f0ee17 100644
--- a/libcxx/test/std/utilities/type.index/type.index.members/ctor.pass.cpp
+++ b/libcxx/test/std/utilities/type.index/type.index.members/ctor.pass.cpp
@@ -16,9 +16,11 @@
 #include <typeindex>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::type_info const & info = typeid(int);
     std::type_index t1(info);
     assert(t1.name() == info.name());
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/type.index/type.index.members/eq.pass.cpp b/libcxx/test/std/utilities/type.index/type.index.members/eq.pass.cpp
index 210d0ab028ce09ebb438d3baec698eb21ff3dfec..97f6448b73e8527a6a3ea7d7b41814f26975caeb 100644
--- a/libcxx/test/std/utilities/type.index/type.index.members/eq.pass.cpp
+++ b/libcxx/test/std/utilities/type.index/type.index.members/eq.pass.cpp
@@ -16,11 +16,13 @@
 #include <typeindex>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::type_index t1 = typeid(int);
     std::type_index t2 = typeid(int);
     std::type_index t3 = typeid(long);
     assert(t1 == t2);
     assert(t1 != t3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/type.index/type.index.members/hash_code.pass.cpp b/libcxx/test/std/utilities/type.index/type.index.members/hash_code.pass.cpp
index f5b6cc35c7d3882715b663992ce10bcc0600beae..0619ff754439df70296d7c0b6740da58542dbce8 100644
--- a/libcxx/test/std/utilities/type.index/type.index.members/hash_code.pass.cpp
+++ b/libcxx/test/std/utilities/type.index/type.index.members/hash_code.pass.cpp
@@ -15,9 +15,11 @@
 #include <typeindex>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::type_info& ti = typeid(int);
     std::type_index t1 = typeid(int);
     assert(t1.hash_code() == ti.hash_code());
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/type.index/type.index.members/lt.pass.cpp b/libcxx/test/std/utilities/type.index/type.index.members/lt.pass.cpp
index 1f631b7b99755038edd3fcf58b6d3623b51c685b..e24b3975e66dd0f717d15dae5a18347b062aee67 100644
--- a/libcxx/test/std/utilities/type.index/type.index.members/lt.pass.cpp
+++ b/libcxx/test/std/utilities/type.index/type.index.members/lt.pass.cpp
@@ -18,7 +18,7 @@
 #include <typeindex>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::type_index t1 = typeid(int);
     std::type_index t2 = typeid(int);
@@ -41,4 +41,6 @@ int main()
         assert( (t1 >  t3));
         assert( (t1 >= t3));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/type.index/type.index.members/name.pass.cpp b/libcxx/test/std/utilities/type.index/type.index.members/name.pass.cpp
index 1b01f52f9f74739075d18d1a1cc44cf118b961ce..ee91629b35cf466329b30dc3f2107d8c3dc48fa2 100644
--- a/libcxx/test/std/utilities/type.index/type.index.members/name.pass.cpp
+++ b/libcxx/test/std/utilities/type.index/type.index.members/name.pass.cpp
@@ -16,9 +16,11 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     const std::type_info& ti = typeid(int);
     std::type_index t1 = typeid(int);
     assert(std::string(t1.name()) == ti.name());
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/type.index/type.index.overview/copy_assign.pass.cpp b/libcxx/test/std/utilities/type.index/type.index.overview/copy_assign.pass.cpp
index b7fbb6f91cf974b9361cd852a0c5afc3181c0dd6..72cae39d045eb28c722f6a3fef945962a4760a5d 100644
--- a/libcxx/test/std/utilities/type.index/type.index.overview/copy_assign.pass.cpp
+++ b/libcxx/test/std/utilities/type.index/type.index.overview/copy_assign.pass.cpp
@@ -15,11 +15,13 @@
 #include <typeindex>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::type_index t1(typeid(int));
     std::type_index t2(typeid(double));
     assert(t2 != t1);
     t2 = t1;
     assert(t2 == t1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/type.index/type.index.overview/copy_ctor.pass.cpp b/libcxx/test/std/utilities/type.index/type.index.overview/copy_ctor.pass.cpp
index 9520cd8f67e9f83c46ec8c4efa30d90a29eb5e49..df0df2e8c92bff00432048dfc168469743d67009 100644
--- a/libcxx/test/std/utilities/type.index/type.index.overview/copy_ctor.pass.cpp
+++ b/libcxx/test/std/utilities/type.index/type.index.overview/copy_ctor.pass.cpp
@@ -15,9 +15,11 @@
 #include <typeindex>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::type_index t1(typeid(int));
     std::type_index t2 = t1;
     assert(t2 == t1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/type.index/type.index.synopsis/hash_type_index.pass.cpp b/libcxx/test/std/utilities/type.index/type.index.synopsis/hash_type_index.pass.cpp
index 333e04b1811faa723b9ae95d4e1b5df12d1b2858..e8ce292cca0e9a6318e4fd02cb8169b2ecfe0642 100644
--- a/libcxx/test/std/utilities/type.index/type.index.synopsis/hash_type_index.pass.cpp
+++ b/libcxx/test/std/utilities/type.index/type.index.synopsis/hash_type_index.pass.cpp
@@ -22,7 +22,7 @@
 #include "poisoned_hash_helper.hpp"
 #endif
 
-int main()
+int main(int, char**)
 {
   {
     typedef std::hash<std::type_index> H;
@@ -34,4 +34,6 @@ int main()
     test_hash_enabled_for_type<std::type_index>(std::type_index(typeid(int)));
   }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utilities.general/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/utilities.general/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/utilities.general/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/utilities.general/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility.requirements/allocator.requirements/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/utility.requirements/allocator.requirements/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/utility.requirements/allocator.requirements/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/utility.requirements/allocator.requirements/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility.requirements/hash.requirements/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/utility.requirements/hash.requirements/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/utility.requirements/hash.requirements/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/utility.requirements/hash.requirements/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility.requirements/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/utility.requirements/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/utility.requirements/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/utility.requirements/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility.requirements/nullablepointer.requirements/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/utility.requirements/nullablepointer.requirements/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/utility.requirements/nullablepointer.requirements/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/utility.requirements/nullablepointer.requirements/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility.requirements/swappable.requirements/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/utility.requirements/swappable.requirements/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/utility.requirements/swappable.requirements/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/utility.requirements/swappable.requirements/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility.requirements/utility.arg.requirements/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/utility.requirements/utility.arg.requirements/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/utility.requirements/utility.arg.requirements/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/utility.requirements/utility.arg.requirements/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/as_const/as_const.fail.cpp b/libcxx/test/std/utilities/utility/as_const/as_const.fail.cpp
index 5f3b78b7245fb32714f10e7b85250e95aa4720cc..1bb2e64c371fd6c06d0bb4e76bbf68a62a42fc61 100644
--- a/libcxx/test/std/utilities/utility/as_const/as_const.fail.cpp
+++ b/libcxx/test/std/utilities/utility/as_const/as_const.fail.cpp
@@ -15,7 +15,9 @@
 
 struct S {int i;};
 
-int main()
+int main(int, char**)
 {
     std::as_const(S{});
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/as_const/as_const.pass.cpp b/libcxx/test/std/utilities/utility/as_const/as_const.pass.cpp
index 284e5b7b3d65cb53687860a16d2a2dc94bfd1d9e..32d240a0b41b97204c85e219850eaedabeeb178d 100644
--- a/libcxx/test/std/utilities/utility/as_const/as_const.pass.cpp
+++ b/libcxx/test/std/utilities/utility/as_const/as_const.pass.cpp
@@ -34,7 +34,7 @@ void test(T& t)
     assert(std::as_const<const volatile T>(t) == t);
 }
 
-int main()
+int main(int, char**)
 {
     int i = 3;
     double d = 4.0;
@@ -42,4 +42,6 @@ int main()
     test(i);
     test(d);
     test(s);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/declval/declval.pass.cpp b/libcxx/test/std/utilities/utility/declval/declval.pass.cpp
index b298d58a018b97712211ac45a331fcaabd80a17d..6509fd4377cca53f2956936bfce515f14075cfa6 100644
--- a/libcxx/test/std/utilities/utility/declval/declval.pass.cpp
+++ b/libcxx/test/std/utilities/utility/declval/declval.pass.cpp
@@ -21,11 +21,13 @@ class A
     A& operator=(const A&);
 };
 
-int main()
+int main(int, char**)
 {
 #if TEST_STD_VER >= 11
     static_assert((std::is_same<decltype(std::declval<A>()), A&&>::value), "");
 #else
     static_assert((std::is_same<decltype(std::declval<A>()), A&>::value), "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/exchange/exchange.pass.cpp b/libcxx/test/std/utilities/utility/exchange/exchange.pass.cpp
index 1defcbfb3392e3d4bd72fd16efe71773ac1e6703..41e8abb43e5162fb6110f61e5fa9da1caa883b06 100644
--- a/libcxx/test/std/utilities/utility/exchange/exchange.pass.cpp
+++ b/libcxx/test/std/utilities/utility/exchange/exchange.pass.cpp
@@ -39,7 +39,7 @@ TEST_CONSTEXPR bool test_constexpr() {
 
 
 
-int main()
+int main(int, char**)
 {
     {
     int v = 12;
@@ -80,4 +80,6 @@ int main()
 #if TEST_STD_VER > 17
     static_assert(test_constexpr());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/forward/forward.fail.cpp b/libcxx/test/std/utilities/utility/forward/forward.fail.cpp
index a689b1d0dfe867e49d5647df04b0d880a6157e10..4efc1b6aad1525192632e71b227d62e7ae4b5811 100644
--- a/libcxx/test/std/utilities/utility/forward/forward.fail.cpp
+++ b/libcxx/test/std/utilities/utility/forward/forward.fail.cpp
@@ -19,7 +19,7 @@ struct A
 A source() {return A();}
 const A csource() {return A();}
 
-int main()
+int main(int, char**)
 {
 #if TEST_STD_VER >= 11
     {
@@ -49,4 +49,6 @@ int main()
         A a;
         std::forward(a); // expected-error {{no matching function for call to 'forward'}}
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/forward/forward.pass.cpp b/libcxx/test/std/utilities/utility/forward/forward.pass.cpp
index 394c016e2c311c00a51a4c29b64817cc88a00b83..b2f7c960392db2c6889c6f1296750fcb158fd7dc 100644
--- a/libcxx/test/std/utilities/utility/forward/forward.pass.cpp
+++ b/libcxx/test/std/utilities/utility/forward/forward.pass.cpp
@@ -41,7 +41,7 @@ constexpr bool test_constexpr_forward() {
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     A a;
     const A ca = A();
@@ -87,4 +87,6 @@ int main()
     static_assert(std::forward<const int&>(i2) == 42, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/forward/forward_03.pass.cpp b/libcxx/test/std/utilities/utility/forward/forward_03.pass.cpp
index c5a2507a750ddea2dd63829af5439bf9735a8d89..522382dc7ed98aba5e0a7127a5e9352533a04a7c 100644
--- a/libcxx/test/std/utilities/utility/forward/forward_03.pass.cpp
+++ b/libcxx/test/std/utilities/utility/forward/forward_03.pass.cpp
@@ -28,7 +28,7 @@ struct eight {one _[8];};
 one test(A&);
 two test(const A&);
 
-int main()
+int main(int, char**)
 {
     A a;
     const A ca = A();
@@ -54,4 +54,6 @@ int main()
     static_assert(sizeof(test(std::forward<const A>(ca))) == 2, "");
     static_assert(sizeof(test(std::forward<const A>(csource()))) == 2, "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/forward/move.fail.cpp b/libcxx/test/std/utilities/utility/forward/move.fail.cpp
index bd8fd46a97e0e19c1b333a7c39de714a6e138d79..86f3cc3e5d0d90b3719e9b3eea93f62d139af17d 100644
--- a/libcxx/test/std/utilities/utility/forward/move.fail.cpp
+++ b/libcxx/test/std/utilities/utility/forward/move.fail.cpp
@@ -24,10 +24,12 @@ const move_only csource() {return move_only();}
 
 void test(move_only) {}
 
-int main()
+int main(int, char**)
 {
     move_only a;
     const move_only ca = move_only();
 
     test(std::move(ca)); // c
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/forward/move.pass.cpp b/libcxx/test/std/utilities/utility/forward/move.pass.cpp
index c98efa1c345cf5486294be47472c247d71cc2c6f..3db61cda27d1e817e766554cd446902e744ea529 100644
--- a/libcxx/test/std/utilities/utility/forward/move.pass.cpp
+++ b/libcxx/test/std/utilities/utility/forward/move.pass.cpp
@@ -62,7 +62,7 @@ constexpr bool test_constexpr_move() {
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     { // Test return type and noexcept.
         static_assert(std::is_same<decltype(std::move(x)), int&&>::value, "");
@@ -117,4 +117,6 @@ int main()
         static_assert(std::move(y) == 42, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/forward/move_if_noexcept.pass.cpp b/libcxx/test/std/utilities/utility/forward/move_if_noexcept.pass.cpp
index 52a276c2412e6a647110d0fe476bc20fc796a7ec..11ea3c58f09726c06cf4e93038cd28853ba57831 100644
--- a/libcxx/test/std/utilities/utility/forward/move_if_noexcept.pass.cpp
+++ b/libcxx/test/std/utilities/utility/forward/move_if_noexcept.pass.cpp
@@ -39,7 +39,7 @@ struct legacy
     legacy(const legacy&);
 };
 
-int main()
+int main(int, char**)
 {
     int i = 0;
     const int ci = 0;
@@ -71,4 +71,6 @@ int main()
     static_assert(i2 == 23, "" );
 #endif
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/operators/rel_ops.pass.cpp b/libcxx/test/std/utilities/utility/operators/rel_ops.pass.cpp
index 9c8dbedcc65bdd6d2bf9f667fef585536eccdf9e..42e808665628dabe7eb8371a3f90e58246d442c5 100644
--- a/libcxx/test/std/utilities/utility/operators/rel_ops.pass.cpp
+++ b/libcxx/test/std/utilities/utility/operators/rel_ops.pass.cpp
@@ -32,7 +32,7 @@ operator < (const A& x, const A& y)
     return x.data_ < y.data_;
 }
 
-int main()
+int main(int, char**)
 {
     using namespace std::rel_ops;
     A a1(1);
@@ -45,4 +45,6 @@ int main()
     assert(a1 <= a2);
     assert(a2 >= a2);
     assert(a2 >= a1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/utility/pairs/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/utility/pairs/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pair.astuple/get_const.fail.cpp b/libcxx/test/std/utilities/utility/pairs/pair.astuple/get_const.fail.cpp
index e14a1c46a7bb695e05ce26324dc2a97454bd6ecc..e186514f0eab29a4d03ed6d10f19ecbd8d5b7689 100644
--- a/libcxx/test/std/utilities/utility/pairs/pair.astuple/get_const.fail.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pair.astuple/get_const.fail.cpp
@@ -17,7 +17,7 @@
 #include <utility>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<int, short> P;
@@ -26,4 +26,6 @@ int main()
         assert(std::get<1>(p) == 4);
         std::get<0>(p) = 5;
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pair.astuple/get_const.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pair.astuple/get_const.pass.cpp
index 2b164deb45719bc73382ca31bd1a2b3b4458b258..d9747b337e86b8606bd838d86b064c55de801310 100644
--- a/libcxx/test/std/utilities/utility/pairs/pair.astuple/get_const.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pair.astuple/get_const.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<int, short> P;
@@ -36,4 +36,6 @@ int main()
         static_assert(std::get<1>(p1) == 4, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pair.astuple/get_const_rv.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pair.astuple/get_const_rv.pass.cpp
index 05c81a23b5862a48f4b053df972157c74e0f7741..a477c5150ab9d306a8dfb83cb71b5f8bc5a0cd74 100644
--- a/libcxx/test/std/utilities/utility/pairs/pair.astuple/get_const_rv.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pair.astuple/get_const_rv.pass.cpp
@@ -23,7 +23,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::pair<std::unique_ptr<int>, short> P;
@@ -62,4 +62,6 @@ int main()
     static_assert(std::get<1>(std::move(p1)) == 4, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pair.astuple/get_non_const.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pair.astuple/get_non_const.pass.cpp
index 45fb7aa7942697fee10db5a960efd634f84b7797..6119cd5c8ce970b4aba21d39bca67a5611a52089 100644
--- a/libcxx/test/std/utilities/utility/pairs/pair.astuple/get_non_const.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pair.astuple/get_non_const.pass.cpp
@@ -29,7 +29,7 @@ struct S {
 constexpr std::pair<int, int> getP () { return { 3, 4 }; }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<int, short> P;
@@ -49,4 +49,6 @@ int main()
     }
 #endif
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pair.astuple/get_rv.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pair.astuple/get_rv.pass.cpp
index 9ca7b4df6df9c1e37042f98d6227488921e03521..e0ce55bba90f85da9c128c30007bd08cff4ef327 100644
--- a/libcxx/test/std/utilities/utility/pairs/pair.astuple/get_rv.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pair.astuple/get_rv.pass.cpp
@@ -20,7 +20,7 @@
 #include <memory>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<std::unique_ptr<int>, short> P;
@@ -28,4 +28,6 @@ int main()
         std::unique_ptr<int> ptr = std::get<0>(std::move(p));
         assert(*ptr == 3);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pair.astuple/pairs.by.type.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pair.astuple/pairs.by.type.pass.cpp
index 99fb2cd225974528be9139bd8cca3f1afa669f67..f2d3359e7a57b274adcf5d10755a0296a52f3f51 100644
--- a/libcxx/test/std/utilities/utility/pairs/pair.astuple/pairs.by.type.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pair.astuple/pairs.by.type.pass.cpp
@@ -16,7 +16,7 @@
 
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::complex<float> cf;
     {
@@ -81,4 +81,6 @@ int main()
     static_assert(std::get<int>(std::move(p)) == 1, "");
     static_assert(std::get<const int>(std::move(p)) == 2, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pair.astuple/pairs.by.type1.fail.cpp b/libcxx/test/std/utilities/utility/pairs/pair.astuple/pairs.by.type1.fail.cpp
index bba71cb8de2261bb2b149e92d72e6a60b78e7d75..dce209921b88bcbf5018102d0e23c226175a2acf 100644
--- a/libcxx/test/std/utilities/utility/pairs/pair.astuple/pairs.by.type1.fail.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pair.astuple/pairs.by.type1.fail.cpp
@@ -12,9 +12,11 @@
 
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::complex<float> cf;
     auto t1 = std::make_pair<int, double> ( 42, 3.4 );
     assert (( std::get<cf>(t1) == cf {1,2} ));  // no such type
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pair.astuple/pairs.by.type2.fail.cpp b/libcxx/test/std/utilities/utility/pairs/pair.astuple/pairs.by.type2.fail.cpp
index c79e0788ce047087ac6ffbd87835eac768548c76..4c2ea88e6b8d67f5448e497508e3715713064a92 100644
--- a/libcxx/test/std/utilities/utility/pairs/pair.astuple/pairs.by.type2.fail.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pair.astuple/pairs.by.type2.fail.cpp
@@ -12,9 +12,11 @@
 
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::complex<float> cf;
     auto t1 = std::make_pair<int, int> ( 42, 43 );
     assert ( std::get<int>(t1) == 42 ); // two ints
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pair.astuple/pairs.by.type3.fail.cpp b/libcxx/test/std/utilities/utility/pairs/pair.astuple/pairs.by.type3.fail.cpp
index 4787d0e2eddf665df652a81fbe073732cdf2fb75..e30b787e1fd7321da97426128c1b14b92f60942c 100644
--- a/libcxx/test/std/utilities/utility/pairs/pair.astuple/pairs.by.type3.fail.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pair.astuple/pairs.by.type3.fail.cpp
@@ -12,9 +12,11 @@
 
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::unique_ptr<int> upint;
     std::pair<upint, int> t(upint(new int(4)), 23);
     upint p = std::get<upint>(t);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pair.astuple/tuple_element.fail.cpp b/libcxx/test/std/utilities/utility/pairs/pair.astuple/tuple_element.fail.cpp
index ba571fda1eb30b10908ec6c65caecbac14205f59..e53ca898d2687f41f3af5a26266ced10d99f55d6 100644
--- a/libcxx/test/std/utilities/utility/pairs/pair.astuple/tuple_element.fail.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pair.astuple/tuple_element.fail.cpp
@@ -14,8 +14,10 @@
 
 #include <utility>
 
-int main()
+int main(int, char**)
 {
     typedef std::pair<int, short> T;
     std::tuple_element<2, T>::type foo; // expected-error@utility:* {{Index out of bounds in std::tuple_element<std::pair<T1, T2>>}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pair.astuple/tuple_element.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pair.astuple/tuple_element.pass.cpp
index 4ba58143442a5001031d490e193bd91898c580d3..1e41e3fda5d448308a1d3bddc53c9f39d8e2c1ab 100644
--- a/libcxx/test/std/utilities/utility/pairs/pair.astuple/tuple_element.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pair.astuple/tuple_element.pass.cpp
@@ -47,8 +47,10 @@ void test()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test<int, short>();
     test<int*, char>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pair.astuple/tuple_size.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pair.astuple/tuple_size.pass.cpp
index a88b845969289c73687dd5ade1bb0d10bd8ddc28..3b95b4749dd74a7b9cbeffa94bf4977937245da6 100644
--- a/libcxx/test/std/utilities/utility/pairs/pair.astuple/tuple_size.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pair.astuple/tuple_size.pass.cpp
@@ -14,7 +14,7 @@
 
 #include <utility>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<int, short> P1;
@@ -32,4 +32,6 @@ int main()
         typedef std::pair<int, short> const volatile P1;
         static_assert((std::tuple_size<P1>::value == 2), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pair.piecewise/piecewise_construct.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pair.piecewise/piecewise_construct.pass.cpp
index 72eb312081eaf6b573a2abffb65f9f435ce1ab01..98f864caf1f03f0eba6b28f555825b7c64ba6ac0 100644
--- a/libcxx/test/std/utilities/utility/pairs/pair.piecewise/piecewise_construct.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pair.piecewise/piecewise_construct.pass.cpp
@@ -41,7 +41,7 @@ public:
     unsigned get_u2() const {return u2_;}
 };
 
-int main()
+int main(int, char**)
 {
     std::pair<A, B> p(std::piecewise_construct,
                       std::make_tuple(4, 'a'),
@@ -51,4 +51,6 @@ int main()
     assert(p.second.get_d() == 3.5);
     assert(p.second.get_u1() == 6u);
     assert(p.second.get_u2() == 2u);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pairs.general/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pairs.general/nothing_to_do.pass.cpp
index f77636c84755e12808762cb4d42868773b35844d..1f764da05d6b5f59e47bc8d5f6f806c2d120315e 100644
--- a/libcxx/test/std/utilities/utility/pairs/pairs.general/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pairs.general/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pairs.pair/U_V.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pairs.pair/U_V.pass.cpp
index 11403c91de04d4dbc9b566544730f8f8cc7ed0da..0f22808de482c64960f693fa2108e9aa373bac69 100644
--- a/libcxx/test/std/utilities/utility/pairs/pairs.pair/U_V.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pairs.pair/U_V.pass.cpp
@@ -46,7 +46,7 @@ struct ImplicitT {
 };
 
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<std::unique_ptr<int>, short*> P;
@@ -96,4 +96,6 @@ int main()
         static_assert(p.second.value == 43, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pairs.pair/assign_const_pair_U_V.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pairs.pair/assign_const_pair_U_V.pass.cpp
index 5af432b991a58fa65169f272e6c447b2f8b33846..834d73dd7f5e45e5398334aca3dc6ba439fec42d 100644
--- a/libcxx/test/std/utilities/utility/pairs/pairs.pair/assign_const_pair_U_V.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pairs.pair/assign_const_pair_U_V.pass.cpp
@@ -20,7 +20,7 @@
 #include "archetypes.hpp"
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<int, short> P1;
@@ -48,4 +48,6 @@ int main()
        assert(p.second.value == -42);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pairs.pair/assign_pair.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pairs.pair/assign_pair.pass.cpp
index db671a1501a8f4f0e9d55a395c36c60494179bd5..f4dfe5e1b941c2bd9e9222a992de48cfa54a4ae6 100644
--- a/libcxx/test/std/utilities/utility/pairs/pairs.pair/assign_pair.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pairs.pair/assign_pair.pass.cpp
@@ -49,7 +49,7 @@ int CountAssign::moved = 0;
 struct Incomplete;
 extern Incomplete inc_obj;
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<CopyAssignable, short> P;
@@ -94,6 +94,8 @@ int main()
         P p(42, inc_obj);
         assert(&p.second == &inc_obj);
     }
+
+  return 0;
 }
 
 struct Incomplete {};
diff --git a/libcxx/test/std/utilities/utility/pairs/pairs.pair/assign_pair_cxx03.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pairs.pair/assign_pair_cxx03.pass.cpp
index 53cc49183f7878715f72c64db4e7a2bae901c857..47f85eaa6b4f497a9a8839c42f9c389ed33965bb 100644
--- a/libcxx/test/std/utilities/utility/pairs/pairs.pair/assign_pair_cxx03.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pairs.pair/assign_pair_cxx03.pass.cpp
@@ -27,7 +27,7 @@ private:
 struct Incomplete;
 extern Incomplete inc_obj;
 
-int main()
+int main(int, char**)
 {
     {
     // Test that we don't constrain the assignment operator in C++03 mode.
@@ -42,6 +42,8 @@ int main()
     P p(42, inc_obj);
     assert(&p.second == &inc_obj);
     }
+
+  return 0;
 }
 
 struct Incomplete {};
diff --git a/libcxx/test/std/utilities/utility/pairs/pairs.pair/assign_rv_pair.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pairs.pair/assign_rv_pair.pass.cpp
index 91427ca7f2c4c9bc628809f7fded708ce2614a02..b4f0c01094d098a8a26a720912135d02ed52fc33 100644
--- a/libcxx/test/std/utilities/utility/pairs/pairs.pair/assign_rv_pair.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pairs.pair/assign_rv_pair.pass.cpp
@@ -45,7 +45,7 @@ struct CountAssign {
 int CountAssign::copied = 0;
 int CountAssign::moved = 0;
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<std::unique_ptr<int>, int> P;
@@ -92,4 +92,6 @@ int main()
         assert(CountAssign::moved == 1);
         assert(CountAssign::copied == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pairs.pair/assign_rv_pair_U_V.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pairs.pair/assign_rv_pair_U_V.pass.cpp
index 7248c2ffa02cbd2869619866e0ea5c002bce82cb..0be0a4e9526c421516172311ea6861d46a1ded41 100644
--- a/libcxx/test/std/utilities/utility/pairs/pairs.pair/assign_rv_pair_U_V.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pairs.pair/assign_rv_pair_U_V.pass.cpp
@@ -29,7 +29,7 @@ struct Derived
 {
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<std::unique_ptr<Derived>, short> P1;
@@ -55,4 +55,6 @@ int main()
        assert(p.first == 42);
        assert(p.second.value == -42);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pairs.pair/const_first_const_second.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pairs.pair/const_first_const_second.pass.cpp
index fcaa44849cb94911d8df18187ffd1b9986b0c172..e147d7558568400a115eec5416fe08f813c40a4c 100644
--- a/libcxx/test/std/utilities/utility/pairs/pairs.pair/const_first_const_second.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pairs.pair/const_first_const_second.pass.cpp
@@ -46,7 +46,7 @@ void test_sfinae() {
     static_assert(test_convertible<P2,   T2,   T1Arg>() == CanConvert, "");
 }
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<float, short*> P;
@@ -94,4 +94,6 @@ int main()
         static_assert(p.second == 10, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pairs.pair/const_first_const_second_cxx03.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pairs.pair/const_first_const_second_cxx03.pass.cpp
index 4759303d663ce335b0f1edabe863a3ea90ccb03d..880179723fbd2c76ea4f01a4854d807b85e531fc 100644
--- a/libcxx/test/std/utilities/utility/pairs/pairs.pair/const_first_const_second_cxx03.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pairs.pair/const_first_const_second_cxx03.pass.cpp
@@ -24,7 +24,7 @@ public:
     bool operator==(const A& a) const {return data_ == a.data_;}
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<float, short*> P;
@@ -38,4 +38,6 @@ int main()
         assert(p.first == A(1));
         assert(p.second == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pairs.pair/const_pair_U_V.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pairs.pair/const_pair_U_V.pass.cpp
index c9c733d8cbec25de6c0642af911ced9b149e1f3e..ce1e86c1a8bb2cf0096438221956f39a21677000 100644
--- a/libcxx/test/std/utilities/utility/pairs/pairs.pair/const_pair_U_V.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pairs.pair/const_pair_U_V.pass.cpp
@@ -53,7 +53,7 @@ struct ImplicitT {
   int value;
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<int, int> P1;
@@ -177,4 +177,6 @@ int main()
         static_assert(p2.second.value == 101, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pairs.pair/const_pair_U_V_cxx03.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pairs.pair/const_pair_U_V_cxx03.pass.cpp
index 8a3fca758ebce5d160bdb0ae4987939e616c0279..9f6498806f31a7b013696424b7a2e632527fe647 100644
--- a/libcxx/test/std/utilities/utility/pairs/pairs.pair/const_pair_U_V_cxx03.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pairs.pair/const_pair_U_V_cxx03.pass.cpp
@@ -15,7 +15,7 @@
 #include <utility>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<int, short> P1;
@@ -25,4 +25,6 @@ int main()
         assert(p2.first == 3);
         assert(p2.second == 4);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pairs.pair/copy_ctor.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pairs.pair/copy_ctor.pass.cpp
index bee96000e52d97723282756e353d879c18858870..81a32901abe6c81b7027b210d1e8f940652dcbdc 100644
--- a/libcxx/test/std/utilities/utility/pairs/pairs.pair/copy_ctor.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pairs.pair/copy_ctor.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<int, short> P1;
@@ -35,4 +35,6 @@ int main()
         static_assert(p2.second == 4, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pairs.pair/default-sfinae.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pairs.pair/default-sfinae.pass.cpp
index b3a248c886298037a44699caebc5a1c5aa6e0e66..70557aa923cd25278e49b134a027f6961fd88e01 100644
--- a/libcxx/test/std/utilities/utility/pairs/pairs.pair/default-sfinae.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pairs.pair/default-sfinae.pass.cpp
@@ -139,7 +139,7 @@ void test_illformed_default()
 }
 
 
-int main()
+int main(int, char**)
 {
     {
         // Check that pair<T, U> can still be used even if
@@ -160,4 +160,6 @@ int main()
         test_is_default_constructible<int>();
         test_is_default_constructible<DefaultSFINAES<int>>();
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pairs.pair/default.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pairs.pair/default.pass.cpp
index 9a07814b12379a0657581417cb5ca1c7a0d83797..dc1f37b666b881b89272607446740c511585f0b5 100644
--- a/libcxx/test/std/utilities/utility/pairs/pairs.pair/default.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pairs.pair/default.pass.cpp
@@ -28,7 +28,7 @@
 #include "test_macros.h"
 #include "archetypes.hpp"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<float, short*> P;
@@ -51,4 +51,6 @@ int main()
         static_assert(!std::is_default_constructible<P2>::value, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pairs.pair/dtor.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pairs.pair/dtor.pass.cpp
index df9cbc757567f78945ffe42732d1f6d7a276d0c2..268ec4294c7f38e0b925296c335f301922557aaa 100644
--- a/libcxx/test/std/utilities/utility/pairs/pairs.pair/dtor.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pairs.pair/dtor.pass.cpp
@@ -26,10 +26,12 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
   static_assert((std::is_trivially_destructible<
       std::pair<int, float> >::value), "");
   static_assert((!std::is_trivially_destructible<
       std::pair<int, std::string> >::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pairs.pair/implicit_deduction_guides.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pairs.pair/implicit_deduction_guides.pass.cpp
index 4b7529388cdc6942711f86d2ca51a033278ac115..ca5a728844e616d954dd72c411cea8e62d61c2b9 100644
--- a/libcxx/test/std/utilities/utility/pairs/pairs.pair/implicit_deduction_guides.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pairs.pair/implicit_deduction_guides.pass.cpp
@@ -39,7 +39,7 @@
 // (6)  explicit pair(pair<U1, U2> const&) -> pair<U1, U2>
 // (7)  pair(pair<U1, U2> &&) -> pair<U1, U2>
 // (8)  explicit pair(pair<U1, U2> &&) -> pair<U1, U2>
-int main()
+int main(int, char**)
 {
   using E = ExplicitTestTypes::TestType;
   static_assert(!std::is_convertible<E const&, E>::value, "");
@@ -76,4 +76,6 @@ int main()
     std::pair p1(std::move(p));
     ASSERT_SAME_TYPE(decltype(p1), std::pair<std::string, E>);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pairs.pair/move_ctor.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pairs.pair/move_ctor.pass.cpp
index 92a0aa42b1402c45fa77eaaad7e39b8efc40701b..53d81ac7aac78b514b86c4bf040dbae679c2848b 100644
--- a/libcxx/test/std/utilities/utility/pairs/pairs.pair/move_ctor.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pairs.pair/move_ctor.pass.cpp
@@ -25,7 +25,7 @@ struct Dummy {
   Dummy(Dummy &&) = default;
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<int, short> P1;
@@ -40,4 +40,6 @@ int main()
         static_assert(!std::is_copy_constructible<P>::value, "");
         static_assert(std::is_move_constructible<P>::value, "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pairs.pair/not_constexpr_cxx11.fail.cpp b/libcxx/test/std/utilities/utility/pairs/pairs.pair/not_constexpr_cxx11.fail.cpp
index 325499eafaff7b3c890fc6964bfb7008637b1462..88d0f964939997b2c768e2dd17d0f4b77865f79e 100644
--- a/libcxx/test/std/utilities/utility/pairs/pairs.pair/not_constexpr_cxx11.fail.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pairs.pair/not_constexpr_cxx11.fail.cpp
@@ -27,7 +27,7 @@ struct ImplicitT {
   int value;
 };
 
-int main()
+int main(int, char**)
 {
     {
         using P = std::pair<int, int>;
@@ -53,4 +53,6 @@ int main()
         constexpr P U_V = {42, 101}; // expected-error {{must be initialized by a constant expression}}
         constexpr P pair_U_V = other; // expected-error {{must be initialized by a constant expression}}
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pairs.pair/piecewise.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pairs.pair/piecewise.pass.cpp
index 3c93eeb3dca69e31567780ae891c617afb702e69..26b02f383ad5beea8946d984a05e6278281ce20a 100644
--- a/libcxx/test/std/utilities/utility/pairs/pairs.pair/piecewise.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pairs.pair/piecewise.pass.cpp
@@ -21,7 +21,7 @@
 #include <utility>
 
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<int, int*> P1;
@@ -32,4 +32,6 @@ int main()
         assert(p3.first == P1(3, nullptr));
         assert(p3.second == P2(nullptr, 4));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pairs.pair/rv_pair_U_V.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pairs.pair/rv_pair_U_V.pass.cpp
index b38ca2a3b726602e015999d06f704d44f4c36b91..0e3d9a1cb70bc8086911bf0127f6f006c2d7f6c3 100644
--- a/libcxx/test/std/utilities/utility/pairs/pairs.pair/rv_pair_U_V.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pairs.pair/rv_pair_U_V.pass.cpp
@@ -63,7 +63,7 @@ struct ImplicitT {
   int value;
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<std::unique_ptr<Derived>, int> P1;
@@ -173,4 +173,6 @@ int main()
         static_assert(p2.second.value == 43, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pairs.pair/special_member_generation_test.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pairs.pair/special_member_generation_test.pass.cpp
index 48ea5fac6e9489badbd9a1456ce9d9587624aa7e..db174e829bd4d98c95089254c6829180ce95b777 100644
--- a/libcxx/test/std/utilities/utility/pairs/pairs.pair/special_member_generation_test.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pairs.pair/special_member_generation_test.pass.cpp
@@ -120,7 +120,9 @@ void test_assignment_operator_exists() {
   }
 }
 
-int main() {
+int main(int, char**) {
   test_constructors_exist();
   test_assignment_operator_exists();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pairs.pair/swap.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pairs.pair/swap.pass.cpp
index 58a5c29326a7bf34b27d721cc95d7b4cfc40ee50..faaae1bc255aa1287943bf2a9fd57dcb559c2fe8 100644
--- a/libcxx/test/std/utilities/utility/pairs/pairs.pair/swap.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pairs.pair/swap.pass.cpp
@@ -24,7 +24,7 @@ struct S {
     bool operator==(int x) const { return i == x; }
     };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<int, short> P1;
@@ -46,4 +46,6 @@ int main()
         assert(p2.first == 3);
         assert(p2.second == 4);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pairs.pair/trivial_copy_move.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pairs.pair/trivial_copy_move.pass.cpp
index e4b444a349f47b62c9f88c3643a2dc670ff17e14..6841f286553887802f555bc3acccf0dca3bc1167 100644
--- a/libcxx/test/std/utilities/utility/pairs/pairs.pair/trivial_copy_move.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pairs.pair/trivial_copy_move.pass.cpp
@@ -26,7 +26,7 @@ struct Dummy {
   Dummy(Dummy &&) = default;
 };
 
-int main()
+int main(int, char**)
 {
     typedef std::pair<int, short> P;
     {
@@ -52,4 +52,6 @@ int main()
 #endif
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pairs.pair/types.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pairs.pair/types.pass.cpp
index abda1d8c3b9c277e813a0c26b40c83cc9e5b5d10..25108de5bbeefa225a923d36017aec1f985c2c10 100644
--- a/libcxx/test/std/utilities/utility/pairs/pairs.pair/types.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pairs.pair/types.pass.cpp
@@ -17,9 +17,11 @@
 #include <utility>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     typedef std::pair<float, short*> P;
     static_assert((std::is_same<P::first_type, float>::value), "");
     static_assert((std::is_same<P::second_type, short*>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pairs.spec/comparison.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pairs.spec/comparison.pass.cpp
index 3b994dfd4dfeb820d4c213b31ce6db0fafd83b24..12d6ab019170df67ce4f31e4ee20b352728c2f4e 100644
--- a/libcxx/test/std/utilities/utility/pairs/pairs.spec/comparison.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pairs.spec/comparison.pass.cpp
@@ -23,7 +23,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<int, short> P;
@@ -94,4 +94,6 @@ int main()
         static_assert( (p1 >= p2), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pairs.spec/make_pair.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pairs.spec/make_pair.pass.cpp
index 3586243f8bacfcc97db18ad9e4f87cbde37d8f97..dff26e57f0b35e78d6c534719f6c843c1deca481 100644
--- a/libcxx/test/std/utilities/utility/pairs/pairs.spec/make_pair.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pairs.spec/make_pair.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<int, short> P1;
@@ -49,4 +49,6 @@ int main()
     }
 #endif
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/pairs/pairs.spec/non_member_swap.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pairs.spec/non_member_swap.pass.cpp
index 62fa942479469bbc2d1862f3c152355021ad6278..87432767217b749caf779ad3722c41107bf02426 100644
--- a/libcxx/test/std/utilities/utility/pairs/pairs.spec/non_member_swap.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pairs.spec/non_member_swap.pass.cpp
@@ -16,7 +16,7 @@
 #include <utility>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::pair<int, short> P1;
@@ -28,4 +28,6 @@ int main()
         assert(p2.first == 3);
         assert(p2.second == 4);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/synopsis.pass.cpp b/libcxx/test/std/utilities/utility/synopsis.pass.cpp
index 90c5e32186d18032a156b6adc487bef1c9bb84dd..5a703e1b2e5802f4dfcffd276d9731e9f5a45dee 100644
--- a/libcxx/test/std/utilities/utility/synopsis.pass.cpp
+++ b/libcxx/test/std/utilities/utility/synopsis.pass.cpp
@@ -13,9 +13,11 @@
 
 #include <utility>
 
-int main()
+int main(int, char**)
 {
     std::initializer_list<int> x;
     (void)x;
+
+  return 0;
 }
 
diff --git a/libcxx/test/std/utilities/utility/utility.inplace/inplace.pass.cpp b/libcxx/test/std/utilities/utility/utility.inplace/inplace.pass.cpp
index 53fa3cf66555f5ccba177e69316b0c027e4169de..155b2c0eb215cb207d5161adac9f70ea5ea96da5 100644
--- a/libcxx/test/std/utilities/utility/utility.inplace/inplace.pass.cpp
+++ b/libcxx/test/std/utilities/utility/utility.inplace/inplace.pass.cpp
@@ -42,7 +42,7 @@ constexpr bool check_tag(Up) {
         && std::is_same<Tp, Up>::value;
 }
 
-int main() {
+int main(int, char**) {
     // test in_place_t
     {
         using T = std::in_place_t;
@@ -70,4 +70,6 @@ int main() {
         static_assert(check_tag<T2>(std::in_place_index<1>));
         static_assert(check_tag<T3>(std::in_place_index<static_cast<size_t>(-1)>));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/utility.swap/swap.pass.cpp b/libcxx/test/std/utilities/utility/utility.swap/swap.pass.cpp
index 9dda5a42c1f7ee5a74f51e9d9cf295358b9709b0..f52af4cb896e9850e76ed474d3ff19804bddbbde 100644
--- a/libcxx/test/std/utilities/utility/utility.swap/swap.pass.cpp
+++ b/libcxx/test/std/utilities/utility/utility.swap/swap.pass.cpp
@@ -62,7 +62,7 @@ constexpr bool can_swap() {
 }
 #endif
 
-int main()
+int main(int, char**)
 {
 
     {
@@ -99,4 +99,6 @@ int main()
         static_assert(noexcept(std::swap(nm, nm)), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/utility/utility.swap/swap_array.pass.cpp b/libcxx/test/std/utilities/utility/utility.swap/swap_array.pass.cpp
index 202e8d33f23637bc42f6bea09bbe8feed0813dfb..015e85a0135713f1db9c80e753109889e00fb9d1 100644
--- a/libcxx/test/std/utilities/utility/utility.swap/swap_array.pass.cpp
+++ b/libcxx/test/std/utilities/utility/utility.swap/swap_array.pass.cpp
@@ -54,7 +54,7 @@ constexpr bool can_swap() {
 #endif
 
 
-int main()
+int main(int, char**)
 {
     {
         int i[3] = {1, 2, 3};
@@ -97,4 +97,6 @@ int main()
         static_assert(noexcept(std::swap(ma, ma)), "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.bad_variant_access/bad_variant_access.pass.cpp b/libcxx/test/std/utilities/variant/variant.bad_variant_access/bad_variant_access.pass.cpp
index 1585e1745baeba1bb18ce93dc89663a60c22d3ea..cb66771fc43e380459a1bb01b4e64d9f5c1e91d8 100644
--- a/libcxx/test/std/utilities/variant/variant.bad_variant_access/bad_variant_access.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.bad_variant_access/bad_variant_access.pass.cpp
@@ -35,11 +35,13 @@ public:
 #include <type_traits>
 #include <variant>
 
-int main() {
+int main(int, char**) {
   static_assert(std::is_base_of<std::exception, std::bad_variant_access>::value,
                 "");
   static_assert(noexcept(std::bad_variant_access{}), "must be noexcept");
   static_assert(noexcept(std::bad_variant_access{}.what()), "must be noexcept");
   std::bad_variant_access ex;
   assert(ex.what());
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.general/nothing_to_do.pass.cpp b/libcxx/test/std/utilities/variant/variant.general/nothing_to_do.pass.cpp
index 0c118a0f5f5252f3d2be285d661146548e67daf5..8002e55766c9c8147203e94280770d10e5265443 100644
--- a/libcxx/test/std/utilities/variant/variant.general/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.general/nothing_to_do.pass.cpp
@@ -7,4 +7,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main() {}
+int main(int, char**) {
+  return 0;
+}
diff --git a/libcxx/test/std/utilities/variant/variant.get/get_if_index.pass.cpp b/libcxx/test/std/utilities/variant/variant.get/get_if_index.pass.cpp
index 505a8cb8e6572efe8d9a00ee2f597f5d7d0a78e2..5210c5f9d8434f8105523c02f56897971c0b3de8 100644
--- a/libcxx/test/std/utilities/variant/variant.get/get_if_index.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.get/get_if_index.pass.cpp
@@ -125,7 +125,9 @@ void test_get_if() {
 #endif
 }
 
-int main() {
+int main(int, char**) {
   test_const_get_if();
   test_get_if();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.get/get_if_type.pass.cpp b/libcxx/test/std/utilities/variant/variant.get/get_if_type.pass.cpp
index 3cb0fc7054e5bfd7b16e6aeb3cbe72a986347948..e7c9671f95c596d57437df96592a70c784222b5b 100644
--- a/libcxx/test/std/utilities/variant/variant.get/get_if_type.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.get/get_if_type.pass.cpp
@@ -123,7 +123,9 @@ void test_get_if() {
 #endif
 }
 
-int main() {
+int main(int, char**) {
   test_const_get_if();
   test_get_if();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.get/get_index.pass.cpp b/libcxx/test/std/utilities/variant/variant.get/get_index.pass.cpp
index a5a629adb96179d6251c74e3842fc07fa5c98ae5..5519c4263b76e934e1d770861aff691bfe977c40 100644
--- a/libcxx/test/std/utilities/variant/variant.get/get_index.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.get/get_index.pass.cpp
@@ -285,10 +285,12 @@ void test_throws_for_all_value_categories() {
 #endif
 }
 
-int main() {
+int main(int, char**) {
   test_const_lvalue_get();
   test_lvalue_get();
   test_rvalue_get();
   test_const_rvalue_get();
   test_throws_for_all_value_categories();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.get/get_type.pass.cpp b/libcxx/test/std/utilities/variant/variant.get/get_type.pass.cpp
index b4cae1027056305d4b49d6a8e026dda1add521e0..76bbbb026e4619afc5937b384e15bf62cac3e8b7 100644
--- a/libcxx/test/std/utilities/variant/variant.get/get_type.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.get/get_type.pass.cpp
@@ -285,10 +285,12 @@ void test_throws_for_all_value_categories() {
 #endif
 }
 
-int main() {
+int main(int, char**) {
   test_const_lvalue_get();
   test_lvalue_get();
   test_rvalue_get();
   test_const_rvalue_get();
   test_throws_for_all_value_categories();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.get/holds_alternative.pass.cpp b/libcxx/test/std/utilities/variant/variant.get/holds_alternative.pass.cpp
index 3e9cfbe9c471df9b59f4f7609b812991549b72f3..b37462069df4faabc5b52396a34f67d66348f534 100644
--- a/libcxx/test/std/utilities/variant/variant.get/holds_alternative.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.get/holds_alternative.pass.cpp
@@ -17,7 +17,7 @@
 #include "test_macros.h"
 #include <variant>
 
-int main() {
+int main(int, char**) {
   {
     using V = std::variant<int>;
     constexpr V v;
@@ -34,4 +34,6 @@ int main() {
     const V v;
     ASSERT_NOEXCEPT(std::holds_alternative<int>(v));
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.hash/enabled_hash.pass.cpp b/libcxx/test/std/utilities/variant/variant.hash/enabled_hash.pass.cpp
index 404f3e7e5b4f5ece842d040f66b8cc9bc9043f08..7e9ffbfa06ebe04d1f35963aa3f07e96021bce4e 100644
--- a/libcxx/test/std/utilities/variant/variant.hash/enabled_hash.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.hash/enabled_hash.pass.cpp
@@ -17,6 +17,8 @@
 
 #include "poisoned_hash_helper.hpp"
 
-int main() {
+int main(int, char**) {
   test_library_hash_specializations_available();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.hash/hash.pass.cpp b/libcxx/test/std/utilities/variant/variant.hash/hash.pass.cpp
index 5acf168ad8c7acc1fdcc76f997f4e9378e589542..edda8d21a24758713e0360d0dee05b2f2b6c9f61 100644
--- a/libcxx/test/std/utilities/variant/variant.hash/hash.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.hash/hash.pass.cpp
@@ -150,9 +150,11 @@ void test_hash_variant_enabled() {
   }
 }
 
-int main() {
+int main(int, char**) {
   test_hash_variant();
   test_hash_variant_duplicate_elements();
   test_hash_monostate();
   test_hash_variant_enabled();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.helpers/variant_alternative.fail.cpp b/libcxx/test/std/utilities/variant/variant.helpers/variant_alternative.fail.cpp
index f7db0d86bee3b3f8b9f93d95bd4f4d385e7f949d..48d5e14e260fedd1fc695a4f24332bc99c9f83f9 100644
--- a/libcxx/test/std/utilities/variant/variant.helpers/variant_alternative.fail.cpp
+++ b/libcxx/test/std/utilities/variant/variant.helpers/variant_alternative.fail.cpp
@@ -25,7 +25,9 @@
 #include <type_traits>
 #include <variant>
 
-int main() {
+int main(int, char**) {
     using V = std::variant<int, void *, const void *, long double>;
     std::variant_alternative<4, V>::type foo;  // expected-error@variant:* {{Index out of bounds in std::variant_alternative<>}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.helpers/variant_alternative.pass.cpp b/libcxx/test/std/utilities/variant/variant.helpers/variant_alternative.pass.cpp
index 841f65cb127dd7b7429dbc739478b4b3b7a8c041..7db07b6b0d4fe9fe450cc72d07a6afa1d066b9b4 100644
--- a/libcxx/test/std/utilities/variant/variant.helpers/variant_alternative.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.helpers/variant_alternative.pass.cpp
@@ -55,7 +55,7 @@ template <class V, size_t I, class E> void test() {
                 "");
 }
 
-int main() {
+int main(int, char**) {
   {
     using V = std::variant<int, void *, const void *, long double>;
     test<V, 0, int>();
@@ -73,4 +73,6 @@ int main() {
     test<V, 4, long double>();
   }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.helpers/variant_size.pass.cpp b/libcxx/test/std/utilities/variant/variant.helpers/variant_size.pass.cpp
index f7e200b241a5a0abf2321e5498399cf3cfad2cac..fb027fb6380a9991a34768c3933a5ff5ad6ccb71 100644
--- a/libcxx/test/std/utilities/variant/variant.helpers/variant_size.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.helpers/variant_size.pass.cpp
@@ -36,8 +36,10 @@ template <class V, size_t E> void test() {
                 "");
 };
 
-int main() {
+int main(int, char**) {
   test<std::variant<>, 0>();
   test<std::variant<void *>, 1>();
   test<std::variant<long, long, void *, double>, 4>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.monostate.relops/relops.pass.cpp b/libcxx/test/std/utilities/variant/variant.monostate.relops/relops.pass.cpp
index 2df4b2bacf5c86f7e4d45f2e88d03b4eb178600c..255f6d0342ec70ded99f90a27ab828e62b84075f 100644
--- a/libcxx/test/std/utilities/variant/variant.monostate.relops/relops.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.monostate.relops/relops.pass.cpp
@@ -23,7 +23,7 @@
 #include <type_traits>
 #include <variant>
 
-int main() {
+int main(int, char**) {
   using M = std::monostate;
   constexpr M m1{};
   constexpr M m2{};
@@ -51,4 +51,6 @@ int main() {
     static_assert((m1 != m2) == false, "");
     ASSERT_NOEXCEPT(m1 != m2);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.monostate/monostate.pass.cpp b/libcxx/test/std/utilities/variant/variant.monostate/monostate.pass.cpp
index 1d7bcaca4db56efb0d198dd8a283421ff9b61ef1..1ba75a77907949cd53dc3604d76bdf03df138d7d 100644
--- a/libcxx/test/std/utilities/variant/variant.monostate/monostate.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.monostate/monostate.pass.cpp
@@ -16,7 +16,7 @@
 #include <type_traits>
 #include <variant>
 
-int main() {
+int main(int, char**) {
   using M = std::monostate;
   static_assert(std::is_trivially_default_constructible<M>::value, "");
   static_assert(std::is_trivially_copy_constructible<M>::value, "");
@@ -24,4 +24,6 @@ int main() {
   static_assert(std::is_trivially_destructible<M>::value, "");
   constexpr M m{};
   ((void)m);
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.relops/relops.pass.cpp b/libcxx/test/std/utilities/variant/variant.relops/relops.pass.cpp
index 1950b5a383da56faa5d9de3d55b2e9460d559b8a..ed32215ffdcd8693304b534dead7efdd79829362 100644
--- a/libcxx/test/std/utilities/variant/variant.relops/relops.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.relops/relops.pass.cpp
@@ -269,7 +269,9 @@ void test_relational() {
 #endif
 }
 
-int main() {
+int main(int, char**) {
   test_equality();
   test_relational();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.relops/relops_bool_conv.fail.cpp b/libcxx/test/std/utilities/variant/variant.relops/relops_bool_conv.fail.cpp
index d03a6b5d5b1280611494c6fb3dff78fafcd17ba2..e46893465bc07af8e3a2811f466dad0d6ccf9c0a 100644
--- a/libcxx/test/std/utilities/variant/variant.relops/relops_bool_conv.fail.cpp
+++ b/libcxx/test/std/utilities/variant/variant.relops/relops_bool_conv.fail.cpp
@@ -72,7 +72,7 @@ inline constexpr MyBoolExplicit operator>=(const ComparesToMyBoolExplicit& LHS,
 }
 
 
-int main() {
+int main(int, char**) {
   using V = std::variant<int, ComparesToMyBoolExplicit>;
   V v1(42);
   V v2(101);
@@ -84,4 +84,6 @@ int main() {
   (void)(v1 <= v2); // expected-note {{here}}
   (void)(v1 > v2); // expected-note {{here}}
   (void)(v1 >= v2); // expected-note {{here}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.synopsis/variant_npos.pass.cpp b/libcxx/test/std/utilities/variant/variant.synopsis/variant_npos.pass.cpp
index aadda7eacbb44cd96b0980470404f652b5796a41..310b6980c1adb7a478dddfb9d44b9f6b58704f98 100644
--- a/libcxx/test/std/utilities/variant/variant.synopsis/variant_npos.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.synopsis/variant_npos.pass.cpp
@@ -15,6 +15,8 @@
 
 #include <variant>
 
-int main() {
+int main(int, char**) {
   static_assert(std::variant_npos == static_cast<std::size_t>(-1), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.assign/T.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.assign/T.pass.cpp
index 67deb3f2c62f331e1e528f803ab9e76be67571c0..6a4bb04862716786121d44d5ba619e1ecb2a06ac 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.assign/T.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.assign/T.pass.cpp
@@ -254,10 +254,12 @@ void test_T_assignment_performs_assignment() {
 #endif // TEST_HAS_NO_EXCEPTIONS
 }
 
-int main() {
+int main(int, char**) {
   test_T_assignment_basic();
   test_T_assignment_performs_construction();
   test_T_assignment_performs_assignment();
   test_T_assignment_noexcept();
   test_T_assignment_sfinae();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.assign/copy.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.assign/copy.pass.cpp
index 6a59989ddad11163bc659ec8a6cf9580f392d045..c36375cf299d9bce97170c08dd6266d91dee2900 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.assign/copy.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.assign/copy.pass.cpp
@@ -590,7 +590,7 @@ void test_constexpr_copy_assignment() {
 #endif // > C++17
 }
 
-int main() {
+int main(int, char**) {
   test_copy_assignment_empty_empty();
   test_copy_assignment_non_empty_empty();
   test_copy_assignment_empty_non_empty();
@@ -599,4 +599,6 @@ int main() {
   test_copy_assignment_sfinae();
   test_copy_assignment_not_noexcept();
   test_constexpr_copy_assignment();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.assign/move.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.assign/move.pass.cpp
index 833883d294fb80a584def7c53242a833dba686b1..c213af4b2e725b9ce6526782f228d089f59b5e4c 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.assign/move.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.assign/move.pass.cpp
@@ -506,7 +506,7 @@ void test_constexpr_move_assignment() {
 #endif // > C++17
 }
 
-int main() {
+int main(int, char**) {
   test_move_assignment_empty_empty();
   test_move_assignment_non_empty_empty();
   test_move_assignment_empty_non_empty();
@@ -515,4 +515,6 @@ int main() {
   test_move_assignment_sfinae();
   test_move_assignment_noexcept();
   test_constexpr_move_assignment();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/T.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/T.pass.cpp
index 7357b9b56c0ed4f6cda2ccf36f98986249729d01..4ebfe052de13129a6aaf886158bdcf7d06677f21 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/T.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/T.pass.cpp
@@ -126,8 +126,10 @@ void test_T_ctor_basic() {
 #endif
 }
 
-int main() {
+int main(int, char**) {
   test_T_ctor_basic();
   test_T_ctor_noexcept();
   test_T_ctor_sfinae();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/copy.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/copy.pass.cpp
index b6471052f64c85bfbb98a8043c5e8475522f5115..00c94ee33c3a58763f5390cb4a4c95c0efcef5ee 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/copy.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/copy.pass.cpp
@@ -260,7 +260,7 @@ void test_constexpr_copy_ctor() {
 #endif // > C++17
 }
 
-int main() {
+int main(int, char**) {
   test_copy_ctor_basic();
   test_copy_ctor_valueless_by_exception();
   test_copy_ctor_sfinae();
@@ -274,4 +274,6 @@ int main() {
   (void) v2;
 }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/default.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/default.pass.cpp
index ec6eb289ba6998e8a7ab55890f417e8205ccd7a0..1766ee1dbc053c1de37c04e9088750057e09a555 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/default.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/default.pass.cpp
@@ -122,9 +122,11 @@ void test_default_ctor_basic() {
   }
 }
 
-int main() {
+int main(int, char**) {
   test_default_ctor_basic();
   test_default_ctor_sfinae();
   test_default_ctor_noexcept();
   test_default_ctor_throws();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/in_place_index_args.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/in_place_index_args.pass.cpp
index a268adcea50c0981d222bac1c1bdb9682033e2fd..cb7d68a659fdeda313299285a2890f26dc9a7433 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/in_place_index_args.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/in_place_index_args.pass.cpp
@@ -104,7 +104,9 @@ void test_ctor_basic() {
   }
 }
 
-int main() {
+int main(int, char**) {
   test_ctor_basic();
   test_ctor_sfinae();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/in_place_index_init_list_args.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/in_place_index_init_list_args.pass.cpp
index 9c7e3faf86272ad66ed4b415408a5311667a38f1..4b78bf5690a1c48e126a8cb600d716b75c1c298f 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/in_place_index_init_list_args.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/in_place_index_init_list_args.pass.cpp
@@ -110,7 +110,9 @@ void test_ctor_basic() {
   }
 }
 
-int main() {
+int main(int, char**) {
   test_ctor_basic();
   test_ctor_sfinae();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/in_place_type_args.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/in_place_type_args.pass.cpp
index 05b2a29ce8f25d78e6f7e0a0e7030661c4e6cdec..ab8fe068831e45c3362b380ee75308be17cc13a0 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/in_place_type_args.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/in_place_type_args.pass.cpp
@@ -114,7 +114,9 @@ void test_ctor_basic() {
   }
 }
 
-int main() {
+int main(int, char**) {
   test_ctor_basic();
   test_ctor_sfinae();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/in_place_type_init_list_args.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/in_place_type_init_list_args.pass.cpp
index c3f3e58d3464a959ddd69d83bbf779484f3dfd3e..4061cfb25283e02f0fbfe8ee27607f65060e34aa 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/in_place_type_init_list_args.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/in_place_type_init_list_args.pass.cpp
@@ -111,7 +111,9 @@ void test_ctor_basic() {
   }
 }
 
-int main() {
+int main(int, char**) {
   test_ctor_basic();
   test_ctor_sfinae();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/move.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/move.pass.cpp
index ecb4a72075531bdbcee0117c73292c9b5a783e48..f146e16d3c00b72bb766f63f705cf2f3695f01b4 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/move.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/move.pass.cpp
@@ -331,10 +331,12 @@ void test_constexpr_move_ctor() {
 #endif // > C++17
 }
 
-int main() {
+int main(int, char**) {
   test_move_ctor_basic();
   test_move_ctor_valueless_by_exception();
   test_move_noexcept();
   test_move_ctor_sfinae();
   test_constexpr_move_ctor();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.dtor/dtor.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.dtor/dtor.pass.cpp
index 8ced5321b69b2d505bbd8e028cd2e896544ba2ae..b26ab0c29bf1ac1eb733f1ac1883f2c7e9e28eb9 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.dtor/dtor.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.dtor/dtor.pass.cpp
@@ -44,7 +44,7 @@ struct TDtor {
 static_assert(!std::is_trivially_copy_constructible<TDtor>::value, "");
 static_assert(std::is_trivially_destructible<TDtor>::value, "");
 
-int main() {
+int main(int, char**) {
   {
     using V = std::variant<int, long, TDtor>;
     static_assert(std::is_trivially_destructible<V>::value, "");
@@ -71,4 +71,6 @@ int main() {
     assert(NonTDtor::count == 0);
     assert(NonTDtor1::count == 1);
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.mod/emplace_index_args.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.mod/emplace_index_args.pass.cpp
index ea84ac940724f28842145dcc07a358ab8a28d4d4..b688c8e7a54e223517bc2e0a50b9b756f328a99e 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.mod/emplace_index_args.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.mod/emplace_index_args.pass.cpp
@@ -159,7 +159,9 @@ void test_basic() {
 #endif
 }
 
-int main() {
+int main(int, char**) {
   test_basic();
   test_emplace_sfinae();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.mod/emplace_index_init_list_args.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.mod/emplace_index_init_list_args.pass.cpp
index 13e3c927c28ec819b8ab4f9447cfa726c14bc99c..9d96a1dc2722502f9b326532b12e32ee02b3db04 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.mod/emplace_index_init_list_args.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.mod/emplace_index_init_list_args.pass.cpp
@@ -92,7 +92,9 @@ void test_basic() {
   assert(&ref3 == &std::get<1>(v));
 }
 
-int main() {
+int main(int, char**) {
   test_basic();
   test_emplace_sfinae();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.mod/emplace_type_args.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.mod/emplace_type_args.pass.cpp
index 7c9034f10a759afef89a4a987e31054dfe4e8e4f..0719f5e7bdc6322130a1431088e2cbbcf3b48ad9 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.mod/emplace_type_args.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.mod/emplace_type_args.pass.cpp
@@ -159,7 +159,9 @@ void test_basic() {
 #endif
 }
 
-int main() {
+int main(int, char**) {
   test_basic();
   test_emplace_sfinae();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.mod/emplace_type_init_list_args.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.mod/emplace_type_init_list_args.pass.cpp
index 85cd25d04decb6872a46d7a4eddc19b811d7acdd..49839eda4f3dcac7b446e3dba5b1615f99a97e85 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.mod/emplace_type_init_list_args.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.mod/emplace_type_init_list_args.pass.cpp
@@ -92,7 +92,9 @@ void test_basic() {
   assert(&ref3 == &std::get<InitList>(v));
 }
 
-int main() {
+int main(int, char**) {
   test_basic();
   test_emplace_sfinae();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.status/index.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.status/index.pass.cpp
index 0afa10138e3f3d216b67558c384adccd7fc66047..6d463ad2788e9cb61ef7a5e18daf766e716c7899 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.status/index.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.status/index.pass.cpp
@@ -25,7 +25,7 @@
 #include "variant_test_helpers.hpp"
 
 
-int main() {
+int main(int, char**) {
   {
     using V = std::variant<int, long>;
     constexpr V v;
@@ -57,4 +57,6 @@ int main() {
     assert(v.index() == std::variant_npos);
   }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.status/valueless_by_exception.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.status/valueless_by_exception.pass.cpp
index 147f380a19ff83ab180f59f4d4e69e0ebfb938b3..2cb730cb0ff9c188f8c6a2049b7879972a6da4bb 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.status/valueless_by_exception.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.status/valueless_by_exception.pass.cpp
@@ -25,7 +25,7 @@
 #include "variant_test_helpers.hpp"
 
 
-int main() {
+int main(int, char**) {
   {
     using V = std::variant<int, long>;
     constexpr V v;
@@ -50,4 +50,6 @@ int main() {
     assert(v.valueless_by_exception());
   }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.swap/swap.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.swap/swap.pass.cpp
index e05cd13e69f403972bd8f4f91935bb9d036714df..4e273f52e5ec05e68e312cf617092930624f9855 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.swap/swap.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.swap/swap.pass.cpp
@@ -589,10 +589,12 @@ void test_swap_noexcept() {
 template class std::variant<int, NotSwappable>;
 #endif
 
-int main() {
+int main(int, char**) {
   test_swap_valueless_by_exception();
   test_swap_same_alternative();
   test_swap_different_alternatives();
   test_swap_sfinae();
   test_swap_noexcept();
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant_array.fail.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant_array.fail.cpp
index a9caeb8b2dbbeddbde2eb683fa6c7ae9e9f50273..ce79e9c4254306308f5fb3243bd08e08f67742bb 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant_array.fail.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant_array.fail.cpp
@@ -23,10 +23,12 @@
 #include "variant_test_helpers.hpp"
 #include "test_convertible.hpp"
 
-int main()
+int main(int, char**)
 {
     // expected-error@variant:* 3 {{static_assert failed}}
     std::variant<int, int[]> v; // expected-note {{requested here}}
     std::variant<int, int[42]> v2; // expected-note {{requested here}}
     std::variant<int, int[][42]> v3; // expected-note {{requested here}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant_empty.fail.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant_empty.fail.cpp
index 85a10eff9af0b743b8c60f6594f1e7aeddb3f1dc..3b93cb0ab70e409ac7a5958d69493459aecb6021 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant_empty.fail.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant_empty.fail.cpp
@@ -18,8 +18,10 @@
 #include "test_macros.h"
 #include "variant_test_helpers.hpp"
 
-int main()
+int main(int, char**)
 {
     // expected-error@variant:* 1 {{static_assert failed}}
     std::variant<> v; // expected-note {{requested here}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant_reference.fail.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant_reference.fail.cpp
index e659f47600a9db10e8df8774c4c256bd92837534..7c2c4669083506567e1b866519cf4a9819930a84 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant_reference.fail.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant_reference.fail.cpp
@@ -18,10 +18,12 @@
 #include "test_macros.h"
 #include "variant_test_helpers.hpp"
 
-int main()
+int main(int, char**)
 {
     // expected-error@variant:* 3 {{static_assert failed}}
     std::variant<int, int&> v; // expected-note {{requested here}}
     std::variant<int, const int &> v2; // expected-note {{requested here}}
     std::variant<int, int&&> v3; // expected-note {{requested here}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant_void.fail.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant_void.fail.cpp
index ce0675d73c6b526a153db25c7ec59323535331aa..27e9c399f8d0f83f6fe3652093d17d5e12086bff 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant_void.fail.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant_void.fail.cpp
@@ -23,10 +23,12 @@
 #include "variant_test_helpers.hpp"
 #include "test_convertible.hpp"
 
-int main()
+int main(int, char**)
 {
     // expected-error@variant:* 3 {{static_assert failed}}
     std::variant<int, void> v; // expected-note {{requested here}}
     std::variant<int, const void> v2; // expected-note {{requested here}}
     std::variant<const volatile void, int> v3; // expected-note {{requested here}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/utilities/variant/variant.visit/visit.pass.cpp b/libcxx/test/std/utilities/variant/variant.visit/visit.pass.cpp
index 198f310e9af49d59c44b34f0dd757446085deafc..15a1de9842c4f1720434d3a01d5bfaff7d086ce7 100644
--- a/libcxx/test/std/utilities/variant/variant.visit/visit.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.visit/visit.pass.cpp
@@ -310,10 +310,12 @@ void test_caller_accepts_nonconst() {
   std::visit(Visitor{}, v);
 }
 
-int main() {
+int main(int, char**) {
   test_call_operator_forwarding();
   test_argument_forwarding();
   test_constexpr();
   test_exceptions();
   test_caller_accepts_nonconst();
+
+  return 0;
 }
diff --git a/libcxx/test/support/nothing_to_do.pass.cpp b/libcxx/test/support/nothing_to_do.pass.cpp
index 1b23133240825050fadd9209a8c4e0d3cb4bdede..f54d71c86da9aa03eaf01c33fcc7ccff23fc99b9 100644
--- a/libcxx/test/support/nothing_to_do.pass.cpp
+++ b/libcxx/test/support/nothing_to_do.pass.cpp
@@ -7,7 +7,9 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
 
diff --git a/libcxx/test/support/test.support/test_convertible_header.pass.cpp b/libcxx/test/support/test.support/test_convertible_header.pass.cpp
index 0158dfe62cebdca8b4dca428d337c0281c146dfa..f2923d50cd41adeebbda4d7fb6077231b8fd5c72 100644
--- a/libcxx/test/support/test.support/test_convertible_header.pass.cpp
+++ b/libcxx/test/support/test.support/test_convertible_header.pass.cpp
@@ -62,6 +62,8 @@ struct ExplicitArgs {
 };
 static_assert(!test_convertible<ExplicitArgs, int, int, int>(), "Must not be convertible");
 
-int main() {
+int main(int, char**) {
     // Nothing to do
+
+  return 0;
 }
diff --git a/libcxx/test/support/test.support/test_demangle.pass.cpp b/libcxx/test/support/test.support/test_demangle.pass.cpp
index 5c62ecbb1182c003c7b8544e4e0f58c0890d178f..2f1b16be9bb93e58179498ff50fd33408f09b024 100644
--- a/libcxx/test/support/test.support/test_demangle.pass.cpp
+++ b/libcxx/test/support/test.support/test_demangle.pass.cpp
@@ -14,7 +14,7 @@ struct MyType {};
 
 template <class T, class U> struct ArgumentListID {};
 
-int main() {
+int main(int, char**) {
   struct {
     const char* raw;
     const char* expect;
@@ -34,4 +34,6 @@ int main() {
     assert(demangle(raw) == expect);
 #endif
   }
+
+  return 0;
 }
diff --git a/libcxx/test/support/test.support/test_macros_header_exceptions.fail.cpp b/libcxx/test/support/test.support/test_macros_header_exceptions.fail.cpp
index 66a01c9673b0fd02ce28ec21aae4c6e8d3dca7ef..b120aabc02f99643066544112d64e62c53b815a7 100644
--- a/libcxx/test/support/test.support/test_macros_header_exceptions.fail.cpp
+++ b/libcxx/test/support/test.support/test_macros_header_exceptions.fail.cpp
@@ -12,7 +12,7 @@
 
 #include "test_macros.h"
 
-int main() {
+int main(int, char**) {
 #if defined(TEST_HAS_NO_EXCEPTIONS)
     try { ((void)0); } catch (...) {} // expected-error {{exceptions disabled}}
 #else
@@ -20,4 +20,6 @@ int main() {
 #error exceptions enabled
 // expected-error@-1 {{exceptions enabled}}
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/support/test.support/test_macros_header_exceptions.pass.cpp b/libcxx/test/support/test.support/test_macros_header_exceptions.pass.cpp
index 274cad82e33b9f196cc3a8a973ac7e50459e8fba..ccdf257dceb48dcae53991ef26032a29eaafc9f7 100644
--- a/libcxx/test/support/test.support/test_macros_header_exceptions.pass.cpp
+++ b/libcxx/test/support/test.support/test_macros_header_exceptions.pass.cpp
@@ -18,6 +18,8 @@
 #error macro defined unexpectedly
 #endif
 
-int main() {
+int main(int, char**) {
     try { ((void)0); } catch (...) {}
+
+  return 0;
 }
diff --git a/libcxx/test/support/test.support/test_macros_header_rtti.fail.cpp b/libcxx/test/support/test.support/test_macros_header_rtti.fail.cpp
index 4096ce43f1093fcfd7556af77593285fcec3fe57..b2f3177af809e17281b67cd964f0f5bac792347b 100644
--- a/libcxx/test/support/test.support/test_macros_header_rtti.fail.cpp
+++ b/libcxx/test/support/test.support/test_macros_header_rtti.fail.cpp
@@ -15,7 +15,7 @@
 struct A { virtual ~A() {} };
 struct B : A {};
 
-int main() {
+int main(int, char**) {
 #if defined(TEST_HAS_NO_RTTI)
     A* ptr = new B;
     (void)dynamic_cast<B*>(ptr); // expected-error{{cannot use dynamic_cast}}
@@ -25,4 +25,6 @@ int main() {
 #error RTTI enabled
 // expected-error@-1{{RTTI enabled}}
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/support/test.support/test_macros_header_rtti.pass.cpp b/libcxx/test/support/test.support/test_macros_header_rtti.pass.cpp
index 9461579939f413c527e285f7cce3b43f720b92b8..e38545f9b9cb80048c0b68eee9d8cf21c71868a2 100644
--- a/libcxx/test/support/test.support/test_macros_header_rtti.pass.cpp
+++ b/libcxx/test/support/test.support/test_macros_header_rtti.pass.cpp
@@ -21,8 +21,10 @@
 struct A { virtual ~A() {} };
 struct B : A {};
 
-int main() {
+int main(int, char**) {
     A* ptr = new B;
     (void)dynamic_cast<B*>(ptr);
     delete ptr;
+
+  return 0;
 }
diff --git a/libcxx/test/support/test.support/test_poisoned_hash_helper.pass.cpp b/libcxx/test/support/test.support/test_poisoned_hash_helper.pass.cpp
index f94f96368eeb2af3d4f0b2b55d0ad6e872a00212..692854b3d26ed2ccca03332b46c3bb06be0242dc 100644
--- a/libcxx/test/support/test.support/test_poisoned_hash_helper.pass.cpp
+++ b/libcxx/test/support/test.support/test_poisoned_hash_helper.pass.cpp
@@ -24,6 +24,8 @@ template <class T> struct has_complete_hash {
   enum { value = is_complete<std::hash<T> >() };
 };
 
-int main() {
+int main(int, char**) {
   static_assert(LibraryHashTypes::assertTrait<has_complete_hash, false>(), "");
+
+  return 0;
 }
diff --git a/libcxx/test/support/test.workarounds/c1xx_broken_is_trivially_copyable.pass.cpp b/libcxx/test/support/test.workarounds/c1xx_broken_is_trivially_copyable.pass.cpp
index 40e50c14e22a04167cb196a5017da058dd257bd3..1b2fd1462e2917687db5e9eb01eb86eedd8b3003 100644
--- a/libcxx/test/support/test.workarounds/c1xx_broken_is_trivially_copyable.pass.cpp
+++ b/libcxx/test/support/test.workarounds/c1xx_broken_is_trivially_copyable.pass.cpp
@@ -25,10 +25,12 @@ struct S {
   S& operator=(S&&) = delete;
 };
 
-int main() {
+int main(int, char**) {
 #if defined(TEST_WORKAROUND_C1XX_BROKEN_IS_TRIVIALLY_COPYABLE)
   static_assert(!std::is_trivially_copyable<S>::value, "");
 #else
   static_assert(std::is_trivially_copyable<S>::value, "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/support/test.workarounds/c1xx_broken_za_ctor_check.pass.cpp b/libcxx/test/support/test.workarounds/c1xx_broken_za_ctor_check.pass.cpp
index 27f1fb640dee786e9a5213f44c7ce714476d9fbf..688a0f798c36a4ed8a86336958fdc936e93cd9f9 100644
--- a/libcxx/test/support/test.workarounds/c1xx_broken_za_ctor_check.pass.cpp
+++ b/libcxx/test/support/test.workarounds/c1xx_broken_za_ctor_check.pass.cpp
@@ -31,10 +31,12 @@ template<class T = int>
 auto test(int) -> decltype(PushFront(std::declval<T>()), std::true_type{});
 auto test(long) -> std::false_type;
 
-int main() {
+int main(int, char**) {
 #if defined(TEST_WORKAROUND_C1XX_BROKEN_ZA_CTOR_CHECK)
     static_assert(!decltype(test(0))::value, "");
 #else
     static_assert(decltype(test(0))::value, "");
 #endif
+
+  return 0;
 }
diff --git a/libcxx/utils/generate_feature_test_macro_components.py b/libcxx/utils/generate_feature_test_macro_components.py
index 2bd80a858d2894b3e9402a1b1ab5b0b96bcffc3f..d923208a1244512a4042fde6013a4d28fcbfb01d 100755
--- a/libcxx/utils/generate_feature_test_macro_components.py
+++ b/libcxx/utils/generate_feature_test_macro_components.py
@@ -865,7 +865,7 @@ def produce_tests():
 
 #endif // TEST_STD_VER > 17
 
-int main() {{}}
+int main(int, char**) { return 0; }
 """.format(script_name=script_name,
            header=h,
            test_tags=test_tags,