On Thu, 1 Oct 2020, Alejandro Colomar via Gcc wrote: > Because 'intmax_t' has a bug > (actually I know GCC rejected the bug report, > but the problem is still there and users should be informed about this) > which is related to __int128. __int128 is not an integer type as defined by any existing version of ISO C, precisely because it's wider than intmax_t, and changing intmax_t would be a big ABI problem (involving new symbol versions for about 100 printf/scanf-related functions in glibc, 200 on platforms with multiple long double variants). See the proposed removal of intmax_t in C2x (accepted in principle at the first virtual Freiburg meeting, but so far without any wording accepted for any specific approach to removal regarding e.g. preprocessor arithmetic and other places depending on intmax_t). That removal would allow __int128 to be considered an extended integer type as defined by C2x and later (with int128_t typedef in <stdint.h>, etc.), if desired. -- Joseph S. Myers joseph@xxxxxxxxxxxxxxxx
