From c0afc6760837d5760416f557305cd8a2c386a7b4 Mon Sep 17 00:00:00 2001
From: Douglas Gregor <dgregor@apple.com>
Date: Thu, 19 Aug 2010 17:02:01 +0000
Subject: [PATCH] We don't actually need to check the implicit object
 argument's conversion a second time for a conversion candidate (with the real
 acting context), because the only problems we would find are access or
 ambiguity issues that won't be diagnosed until we pick this candidate. Add a
 test case to prove it to myself.

llvm-svn: 111526
---
 clang/lib/Sema/SemaOverload.cpp            | 15 ---------------
 clang/test/SemaCXX/conversion-function.cpp | 18 ++++++++++++++++++
 2 files changed, 18 insertions(+), 15 deletions(-)

diff --git a/clang/lib/Sema/SemaOverload.cpp b/clang/lib/Sema/SemaOverload.cpp
index f8f04defb1b6..30979b78d33a 100644
--- a/clang/lib/Sema/SemaOverload.cpp
+++ b/clang/lib/Sema/SemaOverload.cpp
@@ -3767,21 +3767,6 @@ Sema::AddConversionCandidate(CXXConversionDecl *Conversion,
     return;
   }
 
-  // Make sure that the actual object argument initialization will work, when
-  // it comes down to it. This takes into account the actual acting context.
-  if (ConversionContext->getCanonicalDecl()
-                                        != ActingContext->getCanonicalDecl()) {
-    ImplicitConversionSequence ObjectConvertICS
-      = TryObjectArgumentInitialization(From->getType(), Conversion, 
-                                        ActingContext);
-    if (ObjectConvertICS.isBad()) {
-      Candidate.Viable = false;
-      Candidate.FailureKind = ovl_fail_bad_conversion;
-      Candidate.Conversions[0] = ObjectConvertICS;
-      return;
-    }
-  }
-  
   // We won't go through a user-define type conversion function to convert a 
   // derived to base as such conversions are given Conversion Rank. They only
   // go through a copy constructor. 13.3.3.1.2-p4 [over.ics.user]
diff --git a/clang/test/SemaCXX/conversion-function.cpp b/clang/test/SemaCXX/conversion-function.cpp
index 3d544ae03cfe..07281e16d3f3 100644
--- a/clang/test/SemaCXX/conversion-function.cpp
+++ b/clang/test/SemaCXX/conversion-function.cpp
@@ -306,4 +306,22 @@ namespace rdar8018274 {
   void test2(UeberDerived ud) {
     int i = ud; // expected-error{{ambiguous conversion from derived class 'rdar8018274::SuperDerived' to base class 'rdar8018274::Base'}}
   }
+
+  struct Base2 {
+    operator int();
+  };
+
+  struct Base3 {
+    operator int();
+  };
+
+  struct Derived23 : Base2, Base3 { 
+    using Base2::operator int;
+  };
+
+  struct ExtraDerived23 : Derived23 { };
+
+  void test3(ExtraDerived23 ed) {
+    int i = ed;
+  }
 }
-- 
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