$OpenBSD: patch-syshead_h,v 1.1 2009/03/08 15:56:52 martin Exp $
--- syshead.h.orig	Fri Mar  6 13:56:33 2009
+++ syshead.h	Fri Mar  6 13:56:47 2009
@@ -37,7 +37,7 @@
 #endif
 
 /* branch prediction hints */
-#if defined(__GNUC__)
+#if defined(__GNUC__) && __GNUC__ >= 3
 # define likely(x)       __builtin_expect((x),1)
 # define unlikely(x)     __builtin_expect((x),0)
 #else