Don't pass -O0 to clang_cc1, it is the default.

llvm-svn: 189910
diff --git a/clang/test/CodeGenCXX/2007-05-03-VectorInit.cpp b/clang/test/CodeGenCXX/2007-05-03-VectorInit.cpp
index 5bc196f..b22b52a 100644
--- a/clang/test/CodeGenCXX/2007-05-03-VectorInit.cpp
+++ b/clang/test/CodeGenCXX/2007-05-03-VectorInit.cpp
@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -emit-llvm %s -O0 -o -
+// RUN: %clang_cc1 -emit-llvm %s -o -
 // PR1378
 
 typedef float v4sf __attribute__((vector_size(16)));