$OpenBSD: patch-libs_config_test_boost_has_pthread_yield_ipp,v 1.3 2015/07/01 08:41:59 jasper Exp $
--- libs/config/test/boost_has_pthread_yield.ipp.orig	Fri Jun 26 11:34:25 2015
+++ libs/config/test/boost_has_pthread_yield.ipp	Fri Jun 26 11:36:07 2015
@@ -17,8 +17,7 @@ namespace boost_has_pthread_yield{
 void f()
 {
     // this is never called, it just has to compile:
-    int res = pthread_yield();
-    (void)res;
+    pthread_yield();
 }
 
 int test()
