https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116673
Jonathan Wakely <redi at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |NEW Ever confirmed|0 |1 Last reconfirmed| |2024-09-11 --- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> --- Libstdc++ deals with this by providing deleted overloads for those types, so that the std::launder overload that uses __builtin_launder is only used when valid. It would be simpler if the built-in just made those types ill-formed (as we do for type trait built-ins that have type completeness requirements).