[Pixman] Patch to fix test for GCC vector extensions

[Rob Tsuk]

From 662b17d0d691b567a3343af3439f5fbefe989584 Mon Sep 17 00:00:00 2001
From: Rob Tsuk <robtsuk at google.com>
Date: Mon, 7 Aug 2017 07:11:10 -0700
Subject: [PATCH 1/1] Fix test for GCC vector extensions

The previous test was getting a false positive for
clang version 4.
---
 configure.ac | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/configure.ac b/configure.ac
index e833e45..cbebc82 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1101,7 +1101,7 @@ support_for_gcc_vector_extensions=no
 AC_MSG_CHECKING(for GCC vector extensions)
 AC_LINK_IFELSE([AC_LANG_SOURCE([[
 unsigned int __attribute__ ((vector_size(16))) e, a, b;
-int main (void) { e = a - ((b << 27) + (b >> (32 - 27))) + 1; return e[0]; }
+int main (void) { __builtin_shuffle(a,b);e = a - ((b << 27) + (b >> (32 - 27))) + 1; return e[0]; }
 ]])], support_for_gcc_vector_extensions=yes)
 
 if test x$support_for_gcc_vector_extensions = xyes; then
-- 
2.10.0