https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101263
--- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> --- (In reply to Patrick Palka from comment #1) > We might first need to implement P2231 (for constexpr optional) before this > function can be properly constexpr. I have a patch for that, but it's not upstream yet.
