https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70528
--- Comment #6 from Markus Trippelsdorf <trippels at gcc dot gnu.org> ---
(In reply to Patrick Palka from comment #5)
> If comment #1 should be accepted, then should this be accepted too?
>
> template <class T, class U = decltype(T())>
> struct I {
> };
>
> struct J {
> struct K {
> int First = J::N;
> };
> I<K> FunctionMDInfo;
> static const int N = 0;
> };
Clang rejects both.
