Merge pull request #94 from apolukhin/better_noreturn

Fix for undefined BOOST_NORETURN

include/boost/config/suffix.hpp

@@ -628,12 +628,14 @@ namespace std{ using ::type_info; }
 #    if __has_cpp_attribute(noreturn)
 #      define BOOST_NORETURN [[noreturn]]
 #    endif
-#  else
-#    define BOOST_NO_NORETURN
-#    define BOOST_NORETURN
 #  endif
 #endif
 
+#if !defined(BOOST_NORETURN)
+#  define BOOST_NO_NORETURN
+#  define BOOST_NORETURN
+#endif
+
 // Branch prediction hints
 // These macros are intended to wrap conditional expressions that yield true or false
 //