$OpenBSD: patch-boost_concept_detail_general_hpp,v 1.1 2017/05/24 08:30:20 espie Exp $

Index: boost/concept/detail/general.hpp
--- boost/concept/detail/general.hpp.orig
+++ boost/concept/detail/general.hpp
@@ -67,7 +67,7 @@ struct requirement_<void(*)(Model)>
 
 // Version check from https://svn.boost.org/trac/boost/changeset/82886
 // (boost/static_assert.hpp)
-#if defined(__GNUC__) && ((__GNUC__ > 4) || ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7))) 
+#if defined(__GNUC__) && ((__GNUC__ > 4) || ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7))) || defined(__clang__)
 #define BOOST_CONCEPT_UNUSED_TYPEDEF __attribute__((unused))
 #else
 #define BOOST_CONCEPT_UNUSED_TYPEDEF /**/
