https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107817
--- Comment #2 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Jonathan Wakely <r...@gcc.gnu.org>: https://gcc.gnu.org/g:dfc1ea414e0cebccfcffc771ebcefa3d24c9754c commit r13-4243-gdfc1ea414e0cebccfcffc771ebcefa3d24c9754c Author: Jonathan Wakely <jwak...@redhat.com> Date: Tue Nov 22 17:39:43 2022 +0000 libstdc++: Replace std::isdigit and std::isxdigit in <format> [PR107817] These functions aren't usable in constant expressions. Provide our own implementations, based on __from_chars_alnum_to_val from <charconv>. libstdc++-v3/ChangeLog: PR libstdc++/107817 * include/std/charconv (__from_chars_alnum_to_val): Add constexpr for C++20. * include/std/format (__is_digit, __is_xdigit): New functions. (_Spec::_S_parse_width_or_precision): Use __is_digit. (__formatter_fp::parse): Use __is_xdigit.
