[Bug c++/117993] [15 regression] this->x is being rejected in a nested template class with a base of class of the outer templated class

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117993

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #3) 
> I suspect for some reason we think the current instantiation does not have a
> dependent base for some reason.

That is any_dependent_bases_p is returning false for `struct B<T>::C<n>` type.