Use TranslationUnitDecl as DeclContext of builtin functions.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@49856 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index f0e4697..015ba8c 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -166,7 +166,8 @@
     InitBuiltinVaListType();
     
   QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context);  
-  FunctionDecl *New = FunctionDecl::Create(Context, CurContext,
+  FunctionDecl *New = FunctionDecl::Create(Context,
+                                           Context.getTranslationUnitDecl(),
                                            SourceLocation(), II, R,
                                            FunctionDecl::Extern, false, 0);