https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110245
--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> --- So if I read: https://cplusplus.github.io/CWG/issues/2558.html there is still an open question about "Union types shall be initialized such that they have an active member in the result of a constant expression" but I am not 100% sure here.
