Update aosp/master compiler-rt for rebase to r256229

http://b/26987366

Change-Id: I0ca3d7d3f1b7926fcffcb5b467e79958de576437
diff --git a/test/tsan/race_on_barrier.c b/test/tsan/race_on_barrier.c
index cf8a4cb..66fd339 100644
--- a/test/tsan/race_on_barrier.c
+++ b/test/tsan/race_on_barrier.c
@@ -1,4 +1,8 @@
 // RUN: %clang_tsan -O1 %s -o %t && %deflake %run %t | FileCheck %s
+
+// pthread barriers are not available on OS X
+// UNSUPPORTED: darwin
+
 #include "test.h"
 
 pthread_barrier_t B;