$OpenBSD: patch-src_cxx_supportlib_vendor-modified_boost_predef_detail_endian_compat_h,v 1.2 2019/11/12 06:38:20 jeremy Exp $
Index: src/cxx_supportlib/vendor-modified/boost/predef/detail/endian_compat.h
--- src/cxx_supportlib/vendor-modified/boost/predef/detail/endian_compat.h.orig
+++ src/cxx_supportlib/vendor-modified/boost/predef/detail/endian_compat.h
@@ -23,6 +23,15 @@ http://www.boost.org/LICENSE_1_0.txt)
 #if BOOST_ENDIAN_LITTLE_WORD
 #   define BOOST_PDP_ENDIAN
 #   define BOOST_BYTE_ORDER 2134
+#elif defined(__OpenBSD__)
+# include <sys/types.h>
+# if (_BYTE_ORDER == _LITTLE_ENDIAN)
+#  define BOOST_LITTLE_ENDIAN
+#  define BOOST_BYTE_ORDER 1234
+# elif (_BYTE_ORDER == _BIG_ENDIAN)
+#  define BOOST_BIG_ENDIAN
+#  define BOOST_BYTE_ORDER 4321
+# endif
 #endif
 
 #endif
