https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116673
--- Comment #4 from Jonathan Wakely <redi at gcc dot gnu.org> --- (In reply to Jonathan Wakely from comment #2) > I don't remember why I did it that way rather than with static_assert in the > body of std::launder. I must hate fast compilations. Oh, because <new> doesn't include <type_traits>