[Bug c++/92735] unused member variable causes code to compile for member to function for undefined function

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92735

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to Marc Pawlowsky from comment #0)
> on a related not I sent to clang bug report where if value is not static the
> code will compile.

https://bugs.llvm.org/show_bug.cgi?id=44175 (I think that's not a bug).