https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89164
Jonathan Wakely <redi at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Last reconfirmed| |2019-02-04
Ever confirmed|0 |1
--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
As Tim said on SO, I think this is currently undefined, so OK to be accepted.
But it's likely to become ill-formed in C++2a.
