1 files changed, 6 insertions, 0 deletions
diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index 331932a4585..46c5b41f931 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -4330,6 +4330,12 @@ QualType ASTContext::mergeFunctionTypes(QualType lhs, QualType rhs) {
     unsigned proto_nargs = proto->getNumArgs();
     for (unsigned i = 0; i < proto_nargs; ++i) {
       QualType argTy = proto->getArgType(i);
+      
+      // Look at the promotion type of enum types, since that is the type used
+      // to pass enum values.
+      if (const EnumType *Enum = argTy->getAs<EnumType>())
+        argTy = Enum->getDecl()->getPromotionType();
+      
       if (argTy->isPromotableIntegerType() ||
           getCanonicalType(argTy).getUnqualifiedType() == FloatTy)
         return QualType();