MACH_MSGH_BITS   3456 gc/os_dep.c            MACH_MSGH_BITS(MACH_MSG_TYPE_MAKE_SEND,0);
MACH_MSGH_BITS   3482 gc/os_dep.c            MACH_MSGH_BITS(MACH_MSG_TYPE_MAKE_SEND,0);