https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60271
--- Comment #6 from Jonathan Wakely <redi at gcc dot gnu.org> --- http://cplusplus.github.io/LWG/lwg-active.html#2369
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60271
--- Comment #6 from Jonathan Wakely <redi at gcc dot gnu.org> --- http://cplusplus.github.io/LWG/lwg-active.html#2369