https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69881
--- Comment #20 from Jonathan Wakely <redi at gcc dot gnu.org> --- (In reply to Bernd Edlinger from comment #19) > But I am sure that #define __need_offsetof can simply not work. So don't define that. It's undefined behaviour. > I am not sure if it can compile at all, because if I try > there are the same bogus symlinks to missing c/-headers. > > But before the build reaches the point where that matters, > the cstdlib simply includes <stdlib.h> which fails to declare > std::abort. > > Is this c/cstdlib intended for targets that have C++ aware stdlib.h? Yes. > When we leave it as it is, everyone will point with the finger > on us, because it looks like a gcc-bug. > > Alternative would be to detect that any of the 6 known > __need_-defines are present when invoking cstddef and > give an explicit #error, but this mis-use worked previously. > Or maybe a #warning would be a compromise? > > What do you think? I think if we do anything then I prefer your original suggestion to just #undef them. But I'm not yet convinced we should do anything. This already failed with old versions of GCC: // get size_t #define __need_size_t #include <cstddef> // get everything else #include <cstddef> std::max_align_t m;
