it's not target independent code. Are you suggesting to add a config/ to libobjc? IMHO for a not really mantained frontend / target lib that's an excessive requirement.
If necessary, then yes that would be a better solution.Even just keeping the abstraction of the macro and putting definitions of it inside #ifdef at the top of the file would be an improvement over the submitted patch, but IMO still not really compatible with our standards.
Bernd