Update tests to use %clang_cc1 instead of 'clang-cc' or 'clang -cc1'.
 - This is designed to make it obvious that %clang_cc1 is a "test variable"
   which is substituted. It is '%clang_cc1' instead of '%clang -cc1' because it
   can be useful to redefine what gets run as 'clang -cc1' (for example, to set
   a default target).

llvm-svn: 91446
diff --git a/clang/test/Sema/format-attribute-printf0.c b/clang/test/Sema/format-attribute-printf0.c
index fa7eafd..33e8d40 100644
--- a/clang/test/Sema/format-attribute-printf0.c
+++ b/clang/test/Sema/format-attribute-printf0.c
@@ -1,4 +1,4 @@
-//RUN: clang-cc -fsyntax-only -verify %s
+//RUN: %clang_cc1 -fsyntax-only -verify %s
 
 #include <stdarg.h>