[Bug c++/88548] [9 Regression] this accepted in static member functions

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88548

--- Comment #3 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
Related testcase that should also be rejected:

struct S {
  friend auto bar() -> decltype(this);
};