[Accepted at the February, 2023 meeting as part of paper P2797R0.]

(Split off from issue 2687.)

Consider:

  struct A {
    static void f(A);
    void f(this A);

    void g();
  };

  void A::g() {
    (&A::f)(A()); // #1
    (&A::f)();    // #2
  }

It is obvious that #2 is ill-formed, but what about #1? One possible answer is to make such declarations conflict.