[Bug libstdc++/92059] Crash on tr2::dynamic_bitset::operator=() with optimization

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92059

--- Comment #10 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Thanks for the report, the dynamic_bitset is now less broken than it was.

I plan to backport the fixes to the release branches.