https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108303
--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> --- (In reply to Jonathan Wakely from comment #1) > Currently we don't mangle requirements, so the foos all mangle the same and > actually instantiating #1 will break, but for now we can test that they're > considered distinct. That would be PR 100825 .