add boost on mac

macx64/include/boost/coroutine/flags.hpp

@@ -0,0 +1,21 @@
+
+//          Copyright Oliver Kowalke 2009.
+// 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)
+
+#ifndef BOOST_COROUTINES_FLAGS_H
+#define BOOST_COROUTINES_FLAGS_H
+
+namespace boost {
+namespace coroutines {
+
+enum flag_unwind_t
+{
+    stack_unwind = 0,
+    no_stack_unwind
+};
+
+}}
+
+#endif // BOOST_COROUTINES_FLAGS_H