https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110102
--- Comment #9 from Arthur O'Dwyer <arthur.j.odwyer at gmail dot com> --- (In reply to Jason Merrill from comment #8) > (In reply to Arthur O'Dwyer from comment #6) > > I still think it would be nice if GCC stopped supporting > > int f(std::vector<auto> v) { return v[0]; } > > , at least silently by default. > > Fixed (to require -fconcepts-ts) on trunk. Nice! Thank you!