Fix <rdar://problem/5956221> clang ObjC rewriter: Microsoft-specific __fastcall keyword unrecognized.

This fix is C++ specific.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@61816 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/Parser/MicrosoftExtensions.c b/test/Parser/MicrosoftExtensions.c
index 0ff59f7..6b097ab 100644
--- a/test/Parser/MicrosoftExtensions.c
+++ b/test/Parser/MicrosoftExtensions.c
@@ -1,4 +1,4 @@
-// RUN: clang -fsyntax-only -verify -fms-extensions %s
+// RUN: clang -fsyntax-only -verify -fms-extensions -x=objective-c++ %s
 __stdcall int func0();
 int __stdcall func();
 typedef int (__cdecl *tptr)();