Use POSIX argument syntax in test rewrite-includes-messages.c

Invoke diff such that options precede operands. Not doing so leads to
unspecified behaviour under the LSB.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@321830 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/test/Frontend/rewrite-includes-messages.c b/test/Frontend/rewrite-includes-messages.c
index f93fe72e58d5b135ea2b3b115b1d30e0b4c8d144..a3a5cb2eae6c686d0fdfc05ae961d0c40d4d5c01 100644 (file)
--- a/test/Frontend/rewrite-includes-messages.c
+++ b/test/Frontend/rewrite-includes-messages.c
@@ -1,6 +1,6 @@
 // RUN: %clang_cc1 -E -frewrite-includes %s -I%S/Inputs/ | %clang_cc1 -Wall -fsyntax-only -Wunused-macros -x c - 2>&1 > %t.1
 // RUN: %clang_cc1 -I%S/Inputs/ -Wall -Wunused-macros -fsyntax-only %s 2>&1 > %t.2
-// RUN: diff %t.1 %t.2 -u
+// RUN: diff -u %t.1 %t.2
 // expected-no-diagnostics
 
 #include "rewrite-includes-messages.h"