[Bug c++/122752] [16 Regression] Compilation error about class not being a non-union class type for valid C++ code

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122752

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2025-11-18
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Reduced:
```
template <class S>
struct A
{
  typedef S c;
  typename S::n size();
};

template <class S>
inline typename A<S>::c::n A<S>::size()
{
  return 0;
}
```

Confirmed. This works for me with the GCC 15.2.0 release so either it is a bug
introduced afterwards or the report to debian is wrong about the version #
(though maybe debian version # is also wrong because it says 15.2.0).