add boost on mac

macx64/include/boost/context/detail/externc.hpp

@@ -0,0 +1,23 @@
+
+//          Copyright Oliver Kowalke 2014.
+// Distributed under the Boost Software License, Version 1.0.
+//    (See accompanying file LICENSE_1_0.txt or copy at
+//          http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#include <boost/config.hpp>
+#include <boost/context/detail/config.hpp>
+
+#if defined(BOOST_USE_ASAN)
+extern "C" {
+void __sanitizer_start_switch_fiber( void **, const void *, size_t);
+void __sanitizer_finish_switch_fiber( void *, const void **, size_t *);
+}
+#endif
+
+#if defined(BOOST_USE_SEGMENTED_STACKS)
+extern "C" {
+void __splitstack_getcontext( void * [BOOST_CONTEXT_SEGMENTS]);
+void __splitstack_setcontext( void * [BOOST_CONTEXT_SEGMENTS]);
+}
+#endif