Add 'not' to commands that are expected to fail.

This is at least good documentation, but also opens the possibility of
using pipefail.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@185652 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/Parser/parser_overflow.c b/test/Parser/parser_overflow.c
index 7a3d651..9514e80 100644
--- a/test/Parser/parser_overflow.c
+++ b/test/Parser/parser_overflow.c
@@ -1,8 +1,8 @@
-// RUN: %clang_cc1 %s -fsyntax-only -DHUGE 2>&1 | FileCheck %s
-// RUN: %clang_cc1 %s -fsyntax-only 2>&1 | FileCheck %s
-// RUN: %clang_cc1 %s -fsyntax-only -fbracket-depth 299 2>&1 | FileCheck %s
+// RUN: not %clang_cc1 %s -fsyntax-only -DHUGE 2>&1 | FileCheck %s
+// RUN: not %clang_cc1 %s -fsyntax-only 2>&1 | FileCheck %s
+// RUN: not %clang_cc1 %s -fsyntax-only -fbracket-depth 299 2>&1 | FileCheck %s
 // RUN: %clang_cc1 %s -fsyntax-only -fbracket-depth 300
-// RUN: %clang %s -fsyntax-only -fbracket-depth=299 2>&1 | FileCheck %s
+// RUN: not %clang %s -fsyntax-only -fbracket-depth=299 2>&1 | FileCheck %s
 // RUN: %clang %s -fsyntax-only -fbracket-depth=300
 
 void foo(void) {