> In other words you could have malloc return a pointer with the cleanup attribute that automatically frees it at end of scope if it's non-NULL.
That is not, as far as I know, how __attribute__((cleanup)) works. It just invokes the callback when the value goes out of scope. So you can't have malloc return an implicitly cleanup'd pointer unless malloc is a macro, in which case you can do the same with a defer block.
Yeah that's why I said "in theory". You can't do that with the attribute today, but it'd be possible to add that behavior to a standardized variant of it.
That is not, as far as I know, how __attribute__((cleanup)) works. It just invokes the callback when the value goes out of scope. So you can't have malloc return an implicitly cleanup'd pointer unless malloc is a macro, in which case you can do the same with a defer block.