https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77796
--- Comment #4 from Eric Gallager <egallager at gcc dot gnu.org> ---
(In reply to Jonathan Wakely from comment #3)
> (In reply to Eric Gallager from comment #2)
> > (In reply to Eric Gallager from comment #1)
> > > Confirmed. Also, it seems weird that the warning underlines all of
> > > B::destroy, but only the "A" in A::destroy:
> > >
> > > $ /usr/local/bin/g++ -c -Wall -Wextra -pedantic 77796.cc
> > > 77796.cc:11:12: warning: self-comparison always evaluates to true
> > > [-Wtautological-compare]
> > > B::destroy == A::destroy ? 0 : 1
> > > ~~~~~~~~~~~^~~~
> > > $
> >
> > Diagnostics maintainers, do you know what's up with that?
>
> That was PR 87386, fixed on trunk.
Ah, so it is; output is now:
$ /usr/local/bin/g++ -c -Wall -Wextra -pedantic 77796.cc
77796.cc:11:12: warning: self-comparison always evaluates to true
[-Wtautological-compare]
11 | B::destroy == A::destroy ? 0 : 1
| ~~~~~~~~~~ ^~ ~~~~~~~~~~
$
