From 7f976d556ac72f5063a06a475c669e1bba868167 Mon Sep 17 00:00:00 2001
From: Jonathan Peyton <jonathan.l.peyton@intel.com>
Date: Wed, 18 Jan 2017 07:02:21 +0000
Subject: [PATCH] Fix memory error in case of reinit using kmp_set_defaults()
 for lock code.

The lock tables were being reallocated if kmp_set_defaults() was called.
In the env_init code it says that the user should be able to switch between
different KMP_CONSISTENCY_CHECK values which is what this change enables.

llvm-svn: 292349
---
 openmp/runtime/src/kmp_lock.cpp               |  6 +++
 .../test/api/kmp_set_defaults_lock_bug.c      | 53 +++++++++++++++++++
 2 files changed, 59 insertions(+)
 create mode 100644 openmp/runtime/test/api/kmp_set_defaults_lock_bug.c

diff --git a/openmp/runtime/src/kmp_lock.cpp b/openmp/runtime/src/kmp_lock.cpp
index 0055116471c6..ed97d36b170d 100644
--- a/openmp/runtime/src/kmp_lock.cpp
+++ b/openmp/runtime/src/kmp_lock.cpp
@@ -3573,6 +3573,12 @@ __kmp_init_dynamic_user_locks()
         __kmp_indirect_unset = indirect_unset;
         __kmp_indirect_test  = indirect_test;
     }
+    // If the user locks have already been initialized, then return.
+    // Allow the switch between different KMP_CONSISTENCY_CHECK values,
+    // but do not allocate new lock tables if they have already been
+    // allocated.
+    if (__kmp_init_user_locks)
+        return;
 
     // Initialize lock index table
     __kmp_i_lock_table.size = KMP_I_LOCK_CHUNK;
diff --git a/openmp/runtime/test/api/kmp_set_defaults_lock_bug.c b/openmp/runtime/test/api/kmp_set_defaults_lock_bug.c
new file mode 100644
index 000000000000..73a7afb8113f
--- /dev/null
+++ b/openmp/runtime/test/api/kmp_set_defaults_lock_bug.c
@@ -0,0 +1,53 @@
+// RUN: %libomp-compile-and-run
+#include <stdio.h>
+#include "omp_testsuite.h"
+/* The bug occurs if the lock table is reallocated after
+   kmp_set_defaults() is called.  If the table is reallocated,
+   then the lock will not point to a valid lock object after the
+   kmp_set_defaults() call.*/
+omp_lock_t lock;
+
+int test_kmp_set_defaults_lock_bug()
+{
+  /* checks that omp_get_num_threads is equal to the number of
+     threads */
+  int nthreads_lib;
+  int nthreads = 0;
+
+  nthreads_lib = -1;
+
+  #pragma omp parallel
+  {
+    omp_set_lock(&lock);
+    nthreads++;
+    omp_unset_lock(&lock);
+    #pragma omp single
+    {
+      nthreads_lib = omp_get_num_threads ();
+    }  /* end of single */
+  } /* end of parallel */
+  kmp_set_defaults("OMP_NUM_THREADS");
+  #pragma omp parallel
+  {
+    omp_set_lock(&lock);
+    nthreads++;
+    omp_unset_lock(&lock);
+  } /* end of parallel */
+
+  return (nthreads == 2*nthreads_lib);
+}
+
+int main()
+{
+  int i;
+  int num_failed=0;
+  omp_init_lock(&lock);
+
+  for(i = 0; i < REPETITIONS; i++) {
+    if(!test_kmp_set_defaults_lock_bug()) {
+      num_failed++;
+    }
+  }
+  omp_destroy_lock(&lock);
+  return num_failed;
+}
-- 
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