2 files changed, 12 insertions, 2 deletions
diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index ea121165fc2..c64f97a97f1 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -4736,7 +4736,8 @@ QualType ASTContext::mergeTypes(QualType LHS, QualType RHS) {
     return QualType();
   case Type::Vector:
     // FIXME: The merged type should be an ExtVector!
-    if (areCompatVectorTypes(LHS->getAs<VectorType>(), RHS->getAs<VectorType>()))
+    if (areCompatVectorTypes(LHSCan->getAs<VectorType>(),
+                             RHSCan->getAs<VectorType>()))
       return LHS;
     return QualType();
   case Type::ObjCInterface: {
diff --git a/clang/test/Sema/overloadable.c b/clang/test/Sema/overloadable.c
index ff631ed9c85..28c3e4cf8c9 100644
--- a/clang/test/Sema/overloadable.c
+++ b/clang/test/Sema/overloadable.c
@@ -50,4 +50,13 @@ void test_promote(short* sp) {
   promote(sp); // expected-error{{call to unavailable function 'promote'}}
 }
 
-
+// PR6600
+typedef double Double;
+typedef Double DoubleVec __attribute__((vector_size(16)));
+typedef int Int;
+typedef Int IntVec __attribute__((vector_size(16)));
+double magnitude(DoubleVec) __attribute__((__overloadable__));
+double magnitude(IntVec) __attribute__((__overloadable__));
+double test_p6600(DoubleVec d) {
+  return magnitude(d) * magnitude(d);
+}