https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108015
--- Comment #3 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:d61c0357ebc771166d5d48743f80aa339b4183dc commit r13-4574-gd61c0357ebc771166d5d48743f80aa339b4183dc Author: Jonathan Wakely <jwak...@redhat.com> Date: Thu Dec 8 11:55:31 2022 +0000 libstdc++: Remove digit separators [PR108015] These are not valid in C++11 and cause a warning when preprocessing, even though they're inside a skipped group. chrono:2436: warning: missing terminating ' character libstdc++-v3/ChangeLog: PR libstdc++/108015 * include/std/chrono (hh_mm_ss): Remove digit separators.