https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113835
--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> --- (In reply to Richard Biener from comment #1) > GCC 12 was fast (possibly std::vector wasn't constexpr there?) It was constexpr since 12.1.0 So this might be related to Jason's implicit constexpr changes instead.