https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70560
--- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> --- (In reply to Jonathan Wakely from comment #1) > It would be better to fix the lock policy at configure-time, so it is a > constant for a given build of libstdc++. That was done for PR 67843 with r266533, present in gcc 9.1 and later.
