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/CodeGenCXX/const-init-cxx11.cpp b/test/CodeGenCXX/const-init-cxx11.cpp
index 843532b..d21e911 100644
--- a/test/CodeGenCXX/const-init-cxx11.cpp
+++ b/test/CodeGenCXX/const-init-cxx11.cpp
@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -verify -triple x86_64-apple-darwin -emit-llvm -o - %s -std=c++11 | FileCheck %s
+// RUN: not %clang_cc1 -verify -triple x86_64-apple-darwin -emit-llvm -o - %s -std=c++11 | FileCheck %s
 
 // FIXME: The padding in all these objects should be zero-initialized.
 namespace StructUnion {