On 15 Mar 2022 15:54, Joel Sherrill wrote: > The prototype isn't wrapped by __GNU_VISIBLE. Should it be? we're talking about malloc.h here. this is already a non-standard header. the standard malloc APIs are defined in stdlib.h: https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/stdlib.h.html so i'm not sure how much value there is annotating standards in a header that is not in any standard, and whose inclusion clearly declares "i am not conforming to any standards". we could put a disclaimer/explanation at the top of the header file to make this a bit more clear. -mike