Hi FX, > On 10 Jul 2024, at 16:25, FX Coudert <fxcoud...@gmail.com> wrote: > > I found another useless fixincludes on darwin, but this one was a bit harder > to diagnose. GCC trunk applies a fix to <stdio.h> on modern Darwin: it is > stdio_stdarg_h. That fix is actually part of a pair, along with > stdio_va_list, and they appear to work around issues with some old Unix (or > BSD?) headers and the definition of va_list. It is not entirely clear to me > what they fix, but they have been here forever. > > They use various bypass mechanisms, but those are fragile. I have no idea if > the fix is actually needed on any still-supported system, and maybe some > global reviewer might want to remove it. But for now, I only want to bypass > the fix on Darwin: it is useless there, and applying it makes our builds more > fragile (and sensitive to the SDK version). Solaris has already opted out > years ago, and now we do the same. > > To show the madness of this fix, the macOS headers actually contain a comment > that is supposed to trigger the bypass: > > /* DO NOT REMOVE THIS COMMENT: fixincludes needs to see: > * __gnuc_va_list and include <stdarg.h> */ > > This kludge was added to the Apple headers in Libc-391 released around 2004. > But it recently became ineffective, due to the majority of the content of > <stdio.h> being moved into <_stdio.h> (which is not covered by fixincludes). > > Anyway, the only sane thing to do is to disarm this fix on darwin, as the > attached patch does.
Right, if the comment was added in 2004, we have no still-supported OS versions that are relevant, > Tested on aarch64-apple-darwin24, OK to push? Yes, OK for trunk, and backports after some bake time, thanks for the patch, Iain > > FX > > > > PS: With that patch, only two fixincludes remain active for latest darwin: > - handling of __FLT_EVAL_METHOD__ == 16 in math.h (I have reported this as a > bug) > - handling of Apple’s “deprecated” functions: gets, sprintf, tmpnam, > vsprintf, tempnam > > <0001-fixincludes-skip-stdio_stdarg_h-on-darwin.patch>
