https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106179
Jason Merrill <jason at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|NEW |ASSIGNED
Assignee|unassigned at gcc dot gnu.org |jason at gcc dot gnu.org
--- Comment #2 from Jason Merrill <jason at gcc dot gnu.org> ---
The P1787 scope/lookup overhaul clarified that Mat_ in .operator Mat_ is looked
up in the same way as a name mentioned immediately after the ., and since
commaInitializer has dependent type _Tp, we don't know whether "Mat_" is
supposed to name a member type of _Tp or the Mat_ in the enclosing scope, so we
don't know if it's a template. Except that it has to be a type, so it has to
be a template. So yes, it should work.
As should this:
template <class T> struct Mat {
Mat();
};
//template <typename> struct Mat_;
template <typename _Tp> Mat<_Tp>::Mat() {
auto commaInitializer = _Tp().operator Mat_<_Tp>();
}
struct A
{
template <class T> struct Mat_ { };
template <class T> operator Mat_<T>();
};
Mat<A> m;
