[Bug libstdc++/115497] __is_pointer doesn't compile with clang since 014879ea4c86b3b8ab6b61a1226ee5b31e816c8b

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115497

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Ok, clang behavior is an odd one here:
```
template<typename _Tp, bool _IsPtr = __is_pointer(_Tp)>
  struct __is_pointer {};

template<typename _Tp>
inline bool t = __is_pointer(_Tp);

template<bool>
struct ts{};

template<typename _Tp>
  struct is_pointer : ts<__is_pointer(_Tp)> {};

int tt = t<int>;
```

clang does not complain about the use of __is_pointer for variable template t
but does for the base class of is_pointer.