https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109763
Bug ID: 109763
Summary: GCC accepts invalid program involving
decltype(classtype::memberfunction) when used with
concepts
Product: gcc
Version: 13.1.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: jlame646 at gmail dot com
Target Milestone: ---
The following invalid program is accepted by gcc trunk.
https://godbolt.org/z/Ma67TTs5e
```
#include <iostream>
#include <type_traits>
#include <concepts>
template < typename T >
concept test = std::same_as <decltype(T::func), int(int) >;
struct D
{
int func(int);
};
int main()
{
std::cout << test<D>;
}
```
Note `decltype` on a non-static member function is not allowed and so it should
be ill-formed.
