[Bug c++/108550] the type 'const auto' of 'constexpr' variable is not literal

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108550

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2023-01-27

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Reduced all the way (C++14 code):
```
template<class T>
struct is_pointer
{
    static constexpr bool value = false;
};

template<class T, T T1>
struct integral_constant
{
  static constexpr T value = T1;
};

template <class Tp>
constexpr auto is_pointer_v = is_pointer<Tp>::value;

template <class Tp, int = 0>
integral_constant<bool, is_pointer_v<int>> Wrap1();

int main() {
  static_assert(!decltype(Wrap1<int>())::value, ""); // error
  return 0;
}
```

Note the unused default template argument for Wrap1 is needed to produce the
issue. Even the return type of Wrap1 does not need to be dependent either ...