[Bug c++/120306] Copy constructor with requires (!std::copy_constructible) is available

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120306

--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Oh I think MSVC is the only one which rejects this for the correct reason.

And I think libc++'s concept define is incorrect too:
take:
```
#include <concepts>

struct S{
  static constexpr auto t = std::copy_constructible<S>;
};
constexpr auto t1 = std::copy_constructible<S>;
static_assert(S::t == t1);
int main(){}
```

Only libc++ rejects this. MSVC/EDG/GCC all accepts this as valid.