https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109277
--- Comment #12 from Jason Merrill <jason at gcc dot gnu.org> --- Created attachment 54806 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=54806&action=edit patch to allow with -fpermissive Here's an (untested) possible approach to that. I'm about to be away for a week, so I won't be following up in that time.