On Sat, Sep 02, 2023 at 01:37:08PM +0200, René Scharfe wrote: > --- >8 --- > Subject: [PATCH] parse-options: let NULL callback be a noop > > Allow OPTION_CALLBACK options to have a NULL callback function pointer > and do nothing in that case, yet still handle arguments as usual. Use > this to replace parse_opt_noop_cb(). > > We lose the ability to distinguish between a forgotten function pointer > and intentional noop, but that will be caught by a compiler warning > about an unused function in many cases and having an option do nothing > is a benign failure mode. Yeah, my concern would be missing an accidental NULL here. I guess that is pretty unlikely in practice, though. I'd guess the worst case would be somebody accidentally putting the function into the "opt->value" slot where the compiler might then think it is used (though I don't know off-hand if it would complain about an implicit conversion of a function pointer into a "void *"). > We also lose the ability to add a warning to the callback, but we > haven't done that since it was added by 6acec0380b (parseopt: add > OPT_NOOP_NOARG, 2011-09-28), so we probably won't do it soon. We can > add a callback back when we want to show a warning. > > By letting go of features we don't need this patch simplifies the > parse-options API and gets rid of an exported empty function. Your patch looks correct to me. I probably wouldn't have bothered to write it, but now you did. :) My inclination would be to go with my dumb-simple one for this series, and it looks like you may have collected a few slight-more-risky-but-maybe-worthwhile parseopt cleanups on top that could make their own series. -Peff
