$OpenBSD: patch-base_allocator_allocator_shim_cc,v 1.2 2017/03/14 12:18:53 robert Exp $
--- base/allocator/allocator_shim.cc.orig.port	Thu Mar  9 21:04:26 2017
+++ base/allocator/allocator_shim.cc	Fri Mar 10 07:46:16 2017
@@ -77,7 +77,7 @@ inline const allocator::AllocatorDispatch* GetChainHea
   // Unfortunately due to that bug NoBarrier_Load() is mistakenly fully
   // barriered on Linux+Clang, and that causes visible perf regressons.
   return reinterpret_cast<const allocator::AllocatorDispatch*>(
-#if defined(OS_LINUX) && defined(__clang__)
+#if (defined(OS_BSD) || defined(OS_LINUX)) && defined(__clang__)
       *static_cast<const volatile subtle::AtomicWord*>(&g_chain_head)
 #else
       subtle::NoBarrier_Load(&g_chain_head)
