$OpenBSD: patch-src_third_party_s2_hash_h,v 1.1 2013/12/10 17:30:41 joshe Exp $
--- src/third_party/s2/hash.h.orig	Thu Oct 17 11:37:56 2013
+++ src/third_party/s2/hash.h	Mon Oct 28 20:50:09 2013
@@ -7,7 +7,7 @@
 #include "mongo/platform/unordered_set.h"
 #define hash_set mongo::unordered_set
 
-#if defined OS_LINUX || defined OS_MACOSX || defined __sunos__ || defined __freebsd__
+#if defined OS_LINUX || defined OS_MACOSX || defined __sunos__ || defined __freebsd__ || defined __OpenBSD__
 #define HASH_NAMESPACE_START namespace std { namespace tr1 {
 #define HASH_NAMESPACE_END }}
 #elif defined OS_WINDOWS
