Update aosp/master compiler-rt for rebase to r256229

http://b/26987366

Change-Id: I0ca3d7d3f1b7926fcffcb5b467e79958de576437
diff --git a/test/tsan/signal_sync.cc b/test/tsan/signal_sync.cc
index 6ff19d3..b529a18 100644
--- a/test/tsan/signal_sync.cc
+++ b/test/tsan/signal_sync.cc
@@ -1,4 +1,5 @@
 // RUN: %clang_tsan -O1 %s -o %t && %run %t 2>&1 | FileCheck %s
+// UNSUPPORTED: darwin
 #include "test.h"
 #include <signal.h>
 #include <sys/types.h>