Added a flag to identify resolved overloaded function references.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@141171 91177308-0d34-0410-b5e6-96231b3b80d8

10 files changed, 160 insertions, 70 deletions

diff --git a/lib/AST/ASTImporter.cpp b/lib/AST/ASTImporter.cpp
index 37299d9633..e50dcbe4b0 100644
--- a/lib/AST/ASTImporter.cpp
+++ b/lib/AST/ASTImporter.cpp
@@ -3837,14 +3837,17 @@ Expr *ASTNodeImporter::VisitDeclRefExpr(DeclRefExpr *E) {
   QualType T = Importer.Import(E->getType());
   if (T.isNull())
     return 0;
-  
-  return DeclRefExpr::Create(Importer.getToContext(), 
-                             Importer.Import(E->getQualifierLoc()),
-                             ToD,
-                             Importer.Import(E->getLocation()),
-                             T, E->getValueKind(),
-                             FoundD,
-                             /*FIXME:TemplateArgs=*/0);
+
+  DeclRefExpr *DRE = DeclRefExpr::Create(Importer.getToContext(), 
+                                         Importer.Import(E->getQualifierLoc()),
+                                         ToD,
+                                         Importer.Import(E->getLocation()),
+                                         T, E->getValueKind(),
+                                         FoundD,
+                                         /*FIXME:TemplateArgs=*/0);
+  if (E->hadMultipleCandidates())
+    DRE->setHadMultipleCandidates(true);
+  return DRE;
 }
 
 Expr *ASTNodeImporter::VisitIntegerLiteral(IntegerLiteral *E) {
diff --git a/lib/AST/ExprCXX.cpp b/lib/AST/ExprCXX.cpp
index 95b03ee183..ad5ec8b833 100644
--- a/lib/AST/ExprCXX.cpp
+++ b/lib/AST/ExprCXX.cpp
@@ -49,6 +49,7 @@ CXXNewExpr::CXXNewExpr(ASTContext &C, bool globalNew, FunctionDecl *operatorNew,
                        SourceRange TypeIdParens, Expr *arraySize,
                        CXXConstructorDecl *constructor, bool initializer,
                        Expr **constructorArgs, unsigned numConsArgs,
+                       bool HadMultipleCandidates,
                        FunctionDecl *operatorDelete,
                        bool usualArrayDeleteWantsSize, QualType ty,
                        TypeSourceInfo *AllocatedTypeInfo,
@@ -61,6 +62,7 @@ CXXNewExpr::CXXNewExpr(ASTContext &C, bool globalNew, FunctionDecl *operatorNew,
          ty->containsUnexpandedParameterPack()),
     GlobalNew(globalNew), Initializer(initializer),
     UsualArrayDeleteWantsSize(usualArrayDeleteWantsSize),
+    HadMultipleCandidates(HadMultipleCandidates),
     SubExprs(0), OperatorNew(operatorNew),
     OperatorDelete(operatorDelete), Constructor(constructor),
     AllocatedTypeInfo(AllocatedTypeInfo), TypeIdParens(TypeIdParens),
@@ -628,11 +630,13 @@ CXXTemporaryObjectExpr::CXXTemporaryObjectExpr(ASTContext &C,
                                                Expr **Args,
                                                unsigned NumArgs,
                                                SourceRange parenRange,
+                                               bool HadMultipleCandidates,
                                                bool ZeroInitialization)
   : CXXConstructExpr(C, CXXTemporaryObjectExprClass, 
                      Type->getType().getNonReferenceType(), 
                      Type->getTypeLoc().getBeginLoc(),
-                     Cons, false, Args, NumArgs, ZeroInitialization,
+                     Cons, false, Args, NumArgs,
+                     HadMultipleCandidates, ZeroInitialization,
                      CXXConstructExpr::CK_Complete, parenRange),
     Type(Type) {
 }
@@ -646,11 +650,13 @@ CXXConstructExpr *CXXConstructExpr::Create(ASTContext &C, QualType T,
                                            SourceLocation Loc,
                                            CXXConstructorDecl *D, bool Elidable,
                                            Expr **Args, unsigned NumArgs,
+                                           bool HadMultipleCandidates,
                                            bool ZeroInitialization,
                                            ConstructionKind ConstructKind,
                                            SourceRange ParenRange) {
   return new (C) CXXConstructExpr(C, CXXConstructExprClass, T, Loc, D, 
-                                  Elidable, Args, NumArgs, ZeroInitialization,
+                                  Elidable, Args, NumArgs,
+                                  HadMultipleCandidates, ZeroInitialization,
                                   ConstructKind, ParenRange);
 }
 
@@ -658,7 +664,8 @@ CXXConstructExpr::CXXConstructExpr(ASTContext &C, StmtClass SC, QualType T,
                                    SourceLocation Loc,
                                    CXXConstructorDecl *D, bool elidable,
                                    Expr **args, unsigned numargs,
-                                   bool ZeroInitialization, 
+                                   bool HadMultipleCandidates,
+                                   bool ZeroInitialization,
                                    ConstructionKind ConstructKind,
                                    SourceRange ParenRange)
   : Expr(SC, T, VK_RValue, OK_Ordinary,
@@ -666,7 +673,8 @@ CXXConstructExpr::CXXConstructExpr(ASTContext &C, StmtClass SC, QualType T,
          T->isInstantiationDependentType(),
          T->containsUnexpandedParameterPack()),
     Constructor(D), Loc(Loc), ParenRange(ParenRange),  NumArgs(numargs),
-    Elidable(elidable), ZeroInitialization(ZeroInitialization), 
+    Elidable(elidable), HadMultipleCandidates(HadMultipleCandidates),
+    ZeroInitialization(ZeroInitialization),
     ConstructKind(ConstructKind), Args(0)
 {
   if (NumArgs) {
diff --git a/lib/Sema/SemaDeclCXX.cpp b/lib/Sema/SemaDeclCXX.cpp
index bc0383165d..4df525c6f3 100644
--- a/lib/Sema/SemaDeclCXX.cpp
+++ b/lib/Sema/SemaDeclCXX.cpp
@@ -8874,6 +8874,7 @@ ExprResult
 Sema::BuildCXXConstructExpr(SourceLocation ConstructLoc, QualType DeclInitType,
                             CXXConstructorDecl *Constructor,
                             MultiExprArg ExprArgs,
+                            bool HadMultipleCandidates,
                             bool RequiresZeroInit,
                             unsigned ConstructKind,
                             SourceRange ParenRange) {
@@ -8896,8 +8897,8 @@ Sema::BuildCXXConstructExpr(SourceLocation ConstructLoc, QualType DeclInitType,
   }
 
   return BuildCXXConstructExpr(ConstructLoc, DeclInitType, Constructor,
-                               Elidable, move(ExprArgs), RequiresZeroInit,
-                               ConstructKind, ParenRange);
+                               Elidable, move(ExprArgs), HadMultipleCandidates,
+                               RequiresZeroInit, ConstructKind, ParenRange);
 }
 
 /// BuildCXXConstructExpr - Creates a complete call to a constructor,
@@ -8906,6 +8907,7 @@ ExprResult
 Sema::BuildCXXConstructExpr(SourceLocation ConstructLoc, QualType DeclInitType,
                             CXXConstructorDecl *Constructor, bool Elidable,
                             MultiExprArg ExprArgs,
+                            bool HadMultipleCandidates,
                             bool RequiresZeroInit,
                             unsigned ConstructKind,
                             SourceRange ParenRange) {
@@ -8921,20 +8923,21 @@ Sema::BuildCXXConstructExpr(SourceLocation ConstructLoc, QualType DeclInitType,
 
   MarkDeclarationReferenced(ConstructLoc, Constructor);
   return Owned(CXXConstructExpr::Create(Context, DeclInitType, ConstructLoc,
-                                        Constructor, Elidable, Exprs, NumExprs, 
-                                        RequiresZeroInit,
+                                        Constructor, Elidable, Exprs, NumExprs,
+                                        HadMultipleCandidates, RequiresZeroInit,
               static_cast<CXXConstructExpr::ConstructionKind>(ConstructKind),
                                         ParenRange));
 }
 
 bool Sema::InitializeVarWithConstructor(VarDecl *VD,
                                         CXXConstructorDecl *Constructor,
-                                        MultiExprArg Exprs) {
+                                        MultiExprArg Exprs,
+                                        bool HadMultipleCandidates) {
   // FIXME: Provide the correct paren SourceRange when available.
   ExprResult TempResult =
     BuildCXXConstructExpr(VD->getLocation(), VD->getType(), Constructor,
-                          move(Exprs), false, CXXConstructExpr::CK_Complete,
-                          SourceRange());
+                          move(Exprs), HadMultipleCandidates, false,
+                          CXXConstructExpr::CK_Complete, SourceRange());
   if (TempResult.isInvalid())
     return true;
 
diff --git a/lib/Sema/SemaExprCXX.cpp b/lib/Sema/SemaExprCXX.cpp
index 7571f7610c..16d9ae94f2 100644
--- a/lib/Sema/SemaExprCXX.cpp
+++ b/lib/Sema/SemaExprCXX.cpp
@@ -1062,6 +1062,7 @@ Sema::BuildCXXNew(SourceLocation StartLoc, bool UseGlobal,
   bool Init = ConstructorLParen.isValid();
   // --- Choosing a constructor ---
   CXXConstructorDecl *Constructor = 0;
+  bool HadMultipleCandidates = false;
   Expr **ConsArgs = (Expr**)ConstructorArgs.get();
   unsigned NumConsArgs = ConstructorArgs.size();
   ASTOwningVector<Expr*> ConvertedConstructorArgs(*this);
@@ -1108,6 +1109,7 @@ Sema::BuildCXXNew(SourceLocation StartLoc, bool UseGlobal,
       if (CXXConstructExpr *Construct
                     = dyn_cast<CXXConstructExpr>(FullInitExpr)) {
         Constructor = Construct->getConstructor();
+        HadMultipleCandidates = Construct->hadMultipleCandidates();
         for (CXXConstructExpr::arg_iterator A = Construct->arg_begin(),
                                          AEnd = Construct->arg_end();
              A != AEnd; ++A)
@@ -1149,7 +1151,9 @@ Sema::BuildCXXNew(SourceLocation StartLoc, bool UseGlobal,
   return Owned(new (Context) CXXNewExpr(Context, UseGlobal, OperatorNew,
                                         PlaceArgs, NumPlaceArgs, TypeIdParens,
                                         ArraySize, Constructor, Init,
-                                        ConsArgs, NumConsArgs, OperatorDelete,
+                                        ConsArgs, NumConsArgs,
+                                        HadMultipleCandidates,
+                                        OperatorDelete,
                                         UsualArrayDeleteWantsSize,
                                         ResultType, AllocTypeInfo,
                                         StartLoc,
@@ -2048,6 +2052,7 @@ static ExprResult BuildCXXCastArgument(Sema &S,
                                        CastKind Kind,
                                        CXXMethodDecl *Method,
                                        DeclAccessPair FoundDecl,
+                                       bool HadMultipleCandidates,
                                        Expr *From) {
   switch (Kind) {
   default: llvm_unreachable("Unhandled cast kind!");
@@ -2061,7 +2066,7 @@ static ExprResult BuildCXXCastArgument(Sema &S,
 
     ExprResult Result =
     S.BuildCXXConstructExpr(CastLoc, Ty, cast<CXXConstructorDecl>(Method),
-                            move_arg(ConstructorArgs),
+                            move_arg(ConstructorArgs), HadMultipleCandidates,
                             /*ZeroInit*/ false, CXXConstructExpr::CK_Complete,
                             SourceRange());
     if (Result.isInvalid())
@@ -2074,7 +2079,8 @@ static ExprResult BuildCXXCastArgument(Sema &S,
     assert(!From->getType()->isPointerType() && "Arg can't have pointer type!");
 
     // Create an implicit call expr that calls it.
-    ExprResult Result = S.BuildCXXMemberCallExpr(From, FoundDecl, Method);
+    ExprResult Result = S.BuildCXXMemberCallExpr(From, FoundDecl, Method,
+                                                 HadMultipleCandidates);
     if (Result.isInvalid())
       return ExprError();
 
@@ -2145,6 +2151,7 @@ Sema::PerformImplicitConversion(Expr *From, QualType ToType,
                                ToType.getNonReferenceType(),
                                CastKind, cast<CXXMethodDecl>(FD),
                                ICS.UserDefined.FoundConversionFunction,
+                               ICS.UserDefined.HadMultipleCandidates,
                                From);
 
       if (CastArg.isInvalid())
@@ -2204,6 +2211,7 @@ Sema::PerformImplicitConversion(Expr *From, QualType ToType,
       return BuildCXXConstructExpr(/*FIXME:ConstructLoc*/SourceLocation(),
                                    ToType, SCS.CopyConstructor,
                                    move_arg(ConstructorArgs),
+                                   /*HadMultipleCandidates*/ false,
                                    /*ZeroInit*/ false,
                                    CXXConstructExpr::CK_Complete,
                                    SourceRange());
@@ -2211,6 +2219,7 @@ Sema::PerformImplicitConversion(Expr *From, QualType ToType,
     return BuildCXXConstructExpr(/*FIXME:ConstructLoc*/SourceLocation(),
                                  ToType, SCS.CopyConstructor,
                                  MultiExprArg(*this, &From, 1),
+                                 /*HadMultipleCandidates*/ false,
                                  /*ZeroInit*/ false,
                                  CXXConstructExpr::CK_Complete,
                                  SourceRange());
@@ -4520,7 +4529,8 @@ ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base,
 }
 
 ExprResult Sema::BuildCXXMemberCallExpr(Expr *E, NamedDecl *FoundDecl,
-                                        CXXMethodDecl *Method) {
+                                        CXXMethodDecl *Method,
+                                        bool HadMultipleCandidates) {
   ExprResult Exp = PerformObjectArgumentInitialization(E, /*Qualifier=*/0,
                                           FoundDecl, Method);
   if (Exp.isInvalid())
@@ -4530,6 +4540,9 @@ ExprResult Sema::BuildCXXMemberCallExpr(Expr *E, NamedDecl *FoundDecl,
       new (Context) MemberExpr(Exp.take(), /*IsArrow=*/false, Method,
                                SourceLocation(), Method->getType(),
                                VK_RValue, OK_Ordinary);
+  if (HadMultipleCandidates)
+    ME->setHadMultipleCandidates(true);
+
   QualType ResultType = Method->getResultType();
   ExprValueKind VK = Expr::getValueKindForType(ResultType);
   ResultType = ResultType.getNonLValueExprType(Context);
diff --git a/lib/Sema/SemaInit.cpp b/lib/Sema/SemaInit.cpp
index 145a7ecaba..30abef5d83 100644
--- a/lib/Sema/SemaInit.cpp
+++ b/lib/Sema/SemaInit.cpp
@@ -4140,6 +4140,8 @@ static ExprResult CopyObject(Sema &S,
                                    &CurInitExpr, 1, CandidateSet, true);
   }
 
+  bool HadMultipleCandidates = (CandidateSet.size() > 1);
+
   OverloadCandidateSet::iterator Best;
   switch (CandidateSet.BestViableFunction(S, Loc, Best)) {
   case OR_Success:
@@ -4217,6 +4219,7 @@ static ExprResult CopyObject(Sema &S,
   // Actually perform the constructor call.
   CurInit = S.BuildCXXConstructExpr(Loc, T, Constructor, Elidable,
                                     move_arg(ConstructorArgs),
+                                    HadMultipleCandidates,
                                     /*ZeroInit*/ false,
                                     CXXConstructExpr::CK_Complete,
                                     SourceRange());
@@ -4478,6 +4481,7 @@ InitializationSequence::Perform(Sema &S,
       bool IsCopy = false;
       FunctionDecl *Fn = Step->Function.Function;
       DeclAccessPair FoundFn = Step->Function.FoundDecl;
+      bool HadMultipleCandidates = Step->Function.HadMultipleCandidates;
       bool CreatedObject = false;
       if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Fn)) {
         // Build a call to the selected constructor.
@@ -4496,6 +4500,7 @@ InitializationSequence::Perform(Sema &S,
         // Build the an expression that constructs a temporary.
         CurInit = S.BuildCXXConstructExpr(Loc, Step->Type, Constructor,
                                           move_arg(ConstructorArgs),
+                                          HadMultipleCandidates,
                                           /*ZeroInit*/ false,
                                           CXXConstructExpr::CK_Complete,
                                           SourceRange());
@@ -4531,7 +4536,8 @@ InitializationSequence::Perform(Sema &S,
         CurInit = move(CurInitExprRes);
 
         // Build the actual call to the conversion function.
-        CurInit = S.BuildCXXMemberCallExpr(CurInit.get(), FoundFn, Conversion);
+        CurInit = S.BuildCXXMemberCallExpr(CurInit.get(), FoundFn, Conversion,
+                                           HadMultipleCandidates);
         if (CurInit.isInvalid() || !CurInit.get())
           return ExprError();
 
@@ -4616,6 +4622,7 @@ InitializationSequence::Perform(Sema &S,
       unsigned NumArgs = Args.size();
       CXXConstructorDecl *Constructor
         = cast<CXXConstructorDecl>(Step->Function.Function);
+      bool HadMultipleCandidates = Step->Function.HadMultipleCandidates;
 
       // Build a call to the selected constructor.
       ASTOwningVector<Expr*> ConstructorArgs(S);
@@ -4662,6 +4669,7 @@ InitializationSequence::Perform(Sema &S,
                                                                  Exprs,
                                                                  NumExprs,
                                                          Kind.getParenRange(),
+                                                         HadMultipleCandidates,
                                              ConstructorInitRequiresZeroInit));
       } else {
         CXXConstructExpr::ConstructionKind ConstructKind =
@@ -4686,6 +4694,7 @@ InitializationSequence::Perform(Sema &S,
           CurInit = S.BuildCXXConstructExpr(Loc, Entity.getType(),
                                             Constructor, /*Elidable=*/true,
                                             move_arg(ConstructorArgs),
+                                            HadMultipleCandidates,
                                             ConstructorInitRequiresZeroInit,
                                             ConstructKind,
                                             parenRange);
@@ -4693,6 +4702,7 @@ InitializationSequence::Perform(Sema &S,
           CurInit = S.BuildCXXConstructExpr(Loc, Entity.getType(),
                                             Constructor,
                                             move_arg(ConstructorArgs),
+                                            HadMultipleCandidates,
                                             ConstructorInitRequiresZeroInit,
                                             ConstructKind,
                                             parenRange);
diff --git a/lib/Sema/SemaOverload.cpp b/lib/Sema/SemaOverload.cpp
index 6174bbac73..c968498d00 100644
--- a/lib/Sema/SemaOverload.cpp
+++ b/lib/Sema/SemaOverload.cpp
@@ -37,11 +37,14 @@ using namespace sema;
 /// A convenience routine for creating a decayed reference to a
 /// function.
 static ExprResult
-CreateFunctionRefExpr(Sema &S, FunctionDecl *Fn,
+CreateFunctionRefExpr(Sema &S, FunctionDecl *Fn, bool HadMultipleCandidates,
                       SourceLocation Loc = SourceLocation(), 
                       const DeclarationNameLoc &LocInfo = DeclarationNameLoc()){
-  ExprResult E = S.Owned(new (S.Context) DeclRefExpr(Fn, Fn->getType(), 
-                                                     VK_LValue, Loc, LocInfo));
+  DeclRefExpr *DRE = new (S.Context) DeclRefExpr(Fn, Fn->getType(),
+                                                 VK_LValue, Loc, LocInfo);
+  if (HadMultipleCandidates)
+    DRE->setHadMultipleCandidates(true);
+  ExprResult E = S.Owned(DRE);
   E = S.DefaultFunctionArrayConversion(E.take());
   if (E.isInvalid())
     return ExprError();
@@ -2496,6 +2499,8 @@ IsUserDefinedConversion(Sema &S, Expr *From, QualType ToType,
     }
   }
 
+  bool HadMultipleCandidates = (CandidateSet.size() > 1);
+
   OverloadCandidateSet::iterator Best;
   switch (CandidateSet.BestViableFunction(S, From->getLocStart(), Best, true)) {
   case OR_Success:
@@ -2517,6 +2522,7 @@ IsUserDefinedConversion(Sema &S, Expr *From, QualType ToType,
         User.Before = Best->Conversions[0].Standard;
         User.EllipsisConversion = false;
       }
+      User.HadMultipleCandidates = HadMultipleCandidates;
       User.ConversionFunction = Constructor;
       User.FoundConversionFunction = Best->FoundDecl;
       User.After.setAsIdentityConversion();
@@ -2534,6 +2540,7 @@ IsUserDefinedConversion(Sema &S, Expr *From, QualType ToType,
       //   conversion sequence converts the source type to the
       //   implicit object parameter of the conversion function.
       User.Before = Best->Conversions[0].Standard;
+      User.HadMultipleCandidates = HadMultipleCandidates;
       User.ConversionFunction = Conversion;
       User.FoundConversionFunction = Best->FoundDecl;
       User.EllipsisConversion = false;
@@ -3364,6 +3371,8 @@ FindConversionForRefInit(Sema &S, ImplicitConversionSequence &ICS,
                                DeclType, CandidateSet);
   }
 
+  bool HadMultipleCandidates = (CandidateSet.size() > 1);
+
   OverloadCandidateSet::iterator Best;
   switch (CandidateSet.BestViableFunction(S, DeclLoc, Best, true)) {
   case OR_Success:
@@ -3385,6 +3394,7 @@ FindConversionForRefInit(Sema &S, ImplicitConversionSequence &ICS,
     ICS.setUserDefined();
     ICS.UserDefined.Before = Best->Conversions[0].Standard;
     ICS.UserDefined.After = Best->FinalConversion;
+    ICS.UserDefined.HadMultipleCandidates = HadMultipleCandidates;
     ICS.UserDefined.ConversionFunction = Best->Function;
     ICS.UserDefined.FoundConversionFunction = Best->FoundDecl;
     ICS.UserDefined.EllipsisConversion = false;
@@ -4050,6 +4060,8 @@ Sema::ConvertToIntegralOrEnumerationType(SourceLocation Loc, Expr *From,
   const UnresolvedSetImpl *Conversions
     = cast<CXXRecordDecl>(RecordTy->getDecl())->getVisibleConversionFunctions();
 
+  bool HadMultipleCandidates = (Conversions->size() > 1);
+
   for (UnresolvedSetImpl::iterator I = Conversions->begin(),
                                    E = Conversions->end();
        I != E;
@@ -4094,7 +4106,8 @@ Sema::ConvertToIntegralOrEnumerationType(SourceLocation Loc, Expr *From,
         return ExprError();
 
       CheckMemberOperatorAccess(From->getExprLoc(), From, 0, Found);
-      ExprResult Result = BuildCXXMemberCallExpr(From, Found, Conversion);
+      ExprResult Result = BuildCXXMemberCallExpr(From, Found, Conversion,
+                                                 HadMultipleCandidates);
       if (Result.isInvalid())
         return ExprError();
 
@@ -4121,8 +4134,8 @@ Sema::ConvertToIntegralOrEnumerationType(SourceLocation Loc, Expr *From,
         << T << ConvTy->isEnumeralType() << ConvTy << From->getSourceRange();
     }
 
-    ExprResult Result = BuildCXXMemberCallExpr(From, Found,
-                          cast<CXXConversionDecl>(Found->getUnderlyingDecl()));
+    ExprResult Result = BuildCXXMemberCallExpr(From, Found, Conversion,
+                                               HadMultipleCandidates);
     if (Result.isInvalid())
       return ExprError();
 
@@ -4794,6 +4807,7 @@ void Sema::AddSurrogateCandidate(CXXConversionDecl *Conversion,
   Candidate.Conversions[0].setUserDefined();
   Candidate.Conversions[0].UserDefined.Before = ObjectInit.Standard;
   Candidate.Conversions[0].UserDefined.EllipsisConversion = false;
+  Candidate.Conversions[0].UserDefined.HadMultipleCandidates = false;
   Candidate.Conversions[0].UserDefined.ConversionFunction = Conversion;
   Candidate.Conversions[0].UserDefined.FoundConversionFunction = FoundDecl;
   Candidate.Conversions[0].UserDefined.After
@@ -8621,6 +8635,8 @@ Sema::CreateOverloadedUnaryOp(SourceLocation OpLoc, unsigned OpcIn,
   // Add builtin operator candidates.
   AddBuiltinOperatorCandidates(Op, OpLoc, &Args[0], NumArgs, CandidateSet);
 
+  bool HadMultipleCandidates = (CandidateSet.size() > 1);
+
   // Perform overload resolution.
   OverloadCandidateSet::iterator Best;
   switch (CandidateSet.BestViableFunction(*this, OpLoc, Best)) {
@@ -8665,7 +8681,8 @@ Sema::CreateOverloadedUnaryOp(SourceLocation OpLoc, unsigned OpcIn,
       ResultTy = ResultTy.getNonLValueExprType(Context);
 
       // Build the actual expression node.
-      ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl);
+      ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl,
+                                                HadMultipleCandidates);
       if (FnExpr.isInvalid())
         return ExprError();
 
@@ -8869,6 +8886,8 @@ Sema::CreateOverloadedBinOp(SourceLocation OpLoc,
   // Add builtin operator candidates.
   AddBuiltinOperatorCandidates(Op, OpLoc, Args, 2, CandidateSet);
 
+  bool HadMultipleCandidates = (CandidateSet.size() > 1);
+
   // Perform overload resolution.
   OverloadCandidateSet::iterator Best;
   switch (CandidateSet.BestViableFunction(*this, OpLoc, Best)) {
@@ -8930,7 +8949,8 @@ Sema::CreateOverloadedBinOp(SourceLocation OpLoc,
         ResultTy = ResultTy.getNonLValueExprType(Context);
 
         // Build the actual expression node.
-        ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl, OpLoc);
+        ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl,
+                                                  HadMultipleCandidates, OpLoc);
         if (FnExpr.isInvalid())
           return ExprError();
 
@@ -9080,6 +9100,8 @@ Sema::CreateOverloadedArraySubscriptExpr(SourceLocation LLoc,
   // Add builtin operator candidates.
   AddBuiltinOperatorCandidates(OO_Subscript, LLoc, Args, 2, CandidateSet);
 
+  bool HadMultipleCandidates = (CandidateSet.size() > 1);
+
   // Perform overload resolution.
   OverloadCandidateSet::iterator Best;
   switch (CandidateSet.BestViableFunction(*this, LLoc, Best)) {
@@ -9126,7 +9148,9 @@ Sema::CreateOverloadedArraySubscriptExpr(SourceLocation LLoc,
         DeclarationNameLoc LocInfo;
         LocInfo.CXXOperatorName.BeginOpNameLoc = LLoc.getRawEncoding();
         LocInfo.CXXOperatorName.EndOpNameLoc = RLoc.getRawEncoding();
-        ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl, LLoc, LocInfo);
+        ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl,
+                                                  HadMultipleCandidates,
+                                                  LLoc, LocInfo);
         if (FnExpr.isInvalid())
           return ExprError();
 
@@ -9520,6 +9544,8 @@ Sema::BuildCallToObjectOfClassType(Scope *S, Expr *Obj,
     }
   }
 
+  bool HadMultipleCandidates = (CandidateSet.size() > 1);
+
   // Perform overload resolution.
   OverloadCandidateSet::iterator Best;
   switch (CandidateSet.BestViableFunction(*this, Object.get()->getLocStart(),
@@ -9578,7 +9604,8 @@ Sema::BuildCallToObjectOfClassType(Scope *S, Expr *Obj,
 
     // Create an implicit member expr to refer to the conversion operator.
     // and then call it.
-    ExprResult Call = BuildCXXMemberCallExpr(Object.get(), Best->FoundDecl, Conv);
+    ExprResult Call = BuildCXXMemberCallExpr(Object.get(), Best->FoundDecl,
+                                             Conv, HadMultipleCandidates);
     if (Call.isInvalid())
       return ExprError();
 
@@ -9614,7 +9641,8 @@ Sema::BuildCallToObjectOfClassType(Scope *S, Expr *Obj,
   for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx)
     MethodArgs[ArgIdx + 1] = Args[ArgIdx];
 
-  ExprResult NewFn = CreateFunctionRefExpr(*this, Method);
+  ExprResult NewFn = CreateFunctionRefExpr(*this, Method,
+                                           HadMultipleCandidates);
   if (NewFn.isInvalid())
     return true;
 
@@ -9744,6 +9772,8 @@ Sema::BuildOverloadedArrowExpr(Scope *S, Expr *Base, SourceLocation OpLoc) {
                        0, 0, CandidateSet, /*SuppressUserConversions=*/false);
   }
 
+  bool HadMultipleCandidates = (CandidateSet.size() > 1);
+
   // Perform overload resolution.
   OverloadCandidateSet::iterator Best;
   switch (CandidateSet.BestViableFunction(*this, OpLoc, Best)) {
@@ -9791,7 +9821,8 @@ Sema::BuildOverloadedArrowExpr(Scope *S, Expr *Base, SourceLocation OpLoc) {
   Base = BaseResult.take();
 
   // Build the operator call.
-  ExprResult FnExpr = CreateFunctionRefExpr(*this, Method);
+  ExprResult FnExpr = CreateFunctionRefExpr(*this, Method,
+                                            HadMultipleCandidates);
   if (FnExpr.isInvalid())
     return ExprError();
 
@@ -9894,14 +9925,16 @@ Expr *Sema::FixOverloadedFunctionReference(Expr *E, DeclAccessPair Found,
       TemplateArgs = &TemplateArgsBuffer;
     }
 
-    return DeclRefExpr::Create(Context,
-                               ULE->getQualifierLoc(),
-                               Fn,
-                               ULE->getNameLoc(),
-                               Fn->getType(),
-                               VK_LValue,
-                               Found.getDecl(),
-                               TemplateArgs);
+    DeclRefExpr *DRE = DeclRefExpr::Create(Context,
+                                           ULE->getQualifierLoc(),
+                                           Fn,
+                                           ULE->getNameLoc(),
+                                           Fn->getType(),
+                                           VK_LValue,
+                                           Found.getDecl(),
+                                           TemplateArgs);
+    DRE->setHadMultipleCandidates(ULE->getNumDecls() > 1);
+    return DRE;
   }
 
   if (UnresolvedMemberExpr *MemExpr = dyn_cast<UnresolvedMemberExpr>(E)) {
@@ -9918,14 +9951,16 @@ Expr *Sema::FixOverloadedFunctionReference(Expr *E, DeclAccessPair Found,
     // implicit member access, rewrite to a simple decl ref.
     if (MemExpr->isImplicitAccess()) {
       if (cast<CXXMethodDecl>(Fn)->isStatic()) {
-        return DeclRefExpr::Create(Context,
-                                   MemExpr->getQualifierLoc(),
-                                   Fn,
-                                   MemExpr->getMemberLoc(),
-                                   Fn->getType(),
-                                   VK_LValue,
-                                   Found.getDecl(),
-                                   TemplateArgs);
+        DeclRefExpr *DRE = DeclRefExpr::Create(Context,
+                                               MemExpr->getQualifierLoc(),
+                                               Fn,
+                                               MemExpr->getMemberLoc(),
+                                               Fn->getType(),
+                                               VK_LValue,
+                                               Found.getDecl(),
+                                               TemplateArgs);
+        DRE->setHadMultipleCandidates(MemExpr->getNumDecls() > 1);
+        return DRE;
       } else {
         SourceLocation Loc = MemExpr->getMemberLoc();
         if (MemExpr->getQualifier())
@@ -9947,14 +9982,16 @@ Expr *Sema::FixOverloadedFunctionReference(Expr *E, DeclAccessPair Found,
       type = Context.BoundMemberTy;
     }
 
-    return MemberExpr::Create(Context, Base,
-                              MemExpr->isArrow(),
-                              MemExpr->getQualifierLoc(),
-                              Fn,
-                              Found,
-                              MemExpr->getMemberNameInfo(),
-                              TemplateArgs,
-                              type, valueKind, OK_Ordinary);
+    MemberExpr *ME = MemberExpr::Create(Context, Base,
+                                        MemExpr->isArrow(),
+                                        MemExpr->getQualifierLoc(),
+                                        Fn,
+                                        Found,
+                                        MemExpr->getMemberNameInfo(),
+                                        TemplateArgs,
+                                        type, valueKind, OK_Ordinary);
+    ME->setHadMultipleCandidates(true);
+    return ME;
   }
 
   llvm_unreachable("Invalid reference to overloaded function");
diff --git a/lib/Sema/TreeTransform.h b/lib/Sema/TreeTransform.h
index 99ddd23912..62c6d18b59 100644
--- a/lib/Sema/TreeTransform.h
+++ b/lib/Sema/TreeTransform.h
@@ -2031,13 +2031,14 @@ public:
   /// By default, performs semantic analysis to build the new expression.
   /// Subclasses may override this routine to provide different behavior.
   ExprResult RebuildCXXConstructExpr(QualType T,
-                                           SourceLocation Loc,
-                                           CXXConstructorDecl *Constructor,
-                                           bool IsElidable,
-                                           MultiExprArg Args,
-                                           bool RequiresZeroInit,
+                                     SourceLocation Loc,
+                                     CXXConstructorDecl *Constructor,
+                                     bool IsElidable,
+                                     MultiExprArg Args,
+                                     bool HadMultipleCandidates,
+                                     bool RequiresZeroInit,
                              CXXConstructExpr::ConstructionKind ConstructKind,
-                                           SourceRange ParenRange) {
+                                     SourceRange ParenRange) {
     ASTOwningVector<Expr*> ConvertedArgs(SemaRef);
     if (getSema().CompleteConstructorCall(Constructor, move(Args), Loc, 
                                           ConvertedArgs))
@@ -2045,6 +2046,7 @@ public:
     
     return getSema().BuildCXXConstructExpr(Loc, T, Constructor, IsElidable,
                                            move_arg(ConvertedArgs),
+                                           HadMultipleCandidates,
                                            RequiresZeroInit, ConstructKind,
                                            ParenRange);
   }
@@ -7345,6 +7347,7 @@ TreeTransform<Derived>::TransformCXXConstructExpr(CXXConstructExpr *E) {
   return getDerived().RebuildCXXConstructExpr(T, /*FIXME:*/E->getLocStart(),
                                               Constructor, E->isElidable(),
                                               move_arg(Args),
+                                              E->hadMultipleCandidates(),
                                               E->requiresZeroInitialization(),
                                               E->getConstructionKind(),
                                               E->getParenRange());
diff --git a/lib/Serialization/ASTReaderStmt.cpp b/lib/Serialization/ASTReaderStmt.cpp
index e2a78e9d1e..7653d5f290 100644
--- a/lib/Serialization/ASTReaderStmt.cpp
+++ b/lib/Serialization/ASTReaderStmt.cpp
@@ -327,6 +327,7 @@ void ASTStmtReader::VisitDeclRefExpr(DeclRefExpr *E) {
   E->DeclRefExprBits.HasQualifier = Record[Idx++];
   E->DeclRefExprBits.HasFoundDecl = Record[Idx++];
   E->DeclRefExprBits.HasExplicitTemplateArgs = Record[Idx++];
+  E->DeclRefExprBits.HadMultipleCandidates = Record[Idx++];
   unsigned NumTemplateArgs = 0;
   if (E->hasExplicitTemplateArgs())
     NumTemplateArgs = Record[Idx++];
@@ -986,7 +987,8 @@ void ASTStmtReader::VisitCXXConstructExpr(CXXConstructExpr *E) {
     E->setArg(I, Reader.ReadSubExpr());
   E->setConstructor(ReadDeclAs<CXXConstructorDecl>(Record, Idx));
   E->setLocation(ReadSourceLocation(Record, Idx));
-  E->setElidable(Record[Idx++]);  
+  E->setElidable(Record[Idx++]);
+  E->setHadMultipleCandidates(Record[Idx++]);
   E->setRequiresZeroInitialization(Record[Idx++]);
   E->setConstructionKind((CXXConstructExpr::ConstructionKind)Record[Idx++]);
   E->ParenRange = ReadSourceRange(Record, Idx);
@@ -1090,6 +1092,7 @@ void ASTStmtReader::VisitCXXNewExpr(CXXNewExpr *E) {
   E->Initializer = Record[Idx++];
   E->UsualArrayDeleteWantsSize = Record[Idx++];
   bool isArray = Record[Idx++];
+  E->setHadMultipleCandidates(Record[Idx++]);
   unsigned NumPlacementArgs = Record[Idx++];
   unsigned NumCtorArgs = Record[Idx++];
   E->setOperatorNew(ReadDeclAs<FunctionDecl>(Record, Idx));
@@ -1549,7 +1552,7 @@ Stmt *ASTReader::ReadStmtFromStream(Module &F) {
         /*HasFoundDecl=*/Record[ASTStmtReader::NumExprFields + 1],
         /*HasExplicitTemplateArgs=*/Record[ASTStmtReader::NumExprFields + 2],
         /*NumTemplateArgs=*/Record[ASTStmtReader::NumExprFields + 2] ?
-          Record[ASTStmtReader::NumExprFields + 3] : 0);
+          Record[ASTStmtReader::NumExprFields + 4] : 0);
       break;
 
     case EXPR_INTEGER_LITERAL:
@@ -1623,7 +1626,9 @@ Stmt *ASTReader::ReadStmtFromStream(Module &F) {
         for (unsigned i = 0; i != NumTemplateArgs; ++i)
           ArgInfo.addArgument(ReadTemplateArgumentLoc(F, Record, Idx));
       }
-      
+
+      bool HadMultipleCandidates = Record[Idx++];
+
       NamedDecl *FoundD = ReadDeclAs<NamedDecl>(F, Record, Idx);
       AccessSpecifier AS = (AccessSpecifier)Record[Idx++];
       DeclAccessPair FoundDecl = DeclAccessPair::make(FoundD, AS);
@@ -1642,6 +1647,8 @@ Stmt *ASTReader::ReadStmtFromStream(Module &F) {
                              HasExplicitTemplateArgs ? &ArgInfo : 0, T, VK, OK);
       ReadDeclarationNameLoc(F, cast<MemberExpr>(S)->MemberDNLoc,
                              MemberD->getDeclName(), Record, Idx);
+      if (HadMultipleCandidates)
+