https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118463
--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
I think the question comes down to is this invalid even without instantiating
f<B>.
```
struct B{
int y;
};
template<typename T>
void f()
{
k<T>();
}
```
GCC rejects it even without instantiation while clang, MSVC, EDG all accept it
until you actually instantiates `f<B>`.
