[Bug c++/105967] New: Forming a pointer to ref-qualified member function using a function typedef ignores the qualifier

[Bug c++/105967] New: Forming a pointer to ref-qualified member function using a function typedef ignores the qualifier

[iamsupermouse at mail dot ru]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105967

            Bug ID: 105967
           Summary: Forming a pointer to ref-qualified member function
                    using a function typedef ignores the qualifier
           Product: gcc
           Version: 12.1.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: iamsupermouse at mail dot ru
  Target Milestone: ---

Consider following code:

    #include <type_traits>

    struct A {};
    using F = void() &; 
    static_assert(std::is_same_v<F A::*, void(A::*)() &>);

GCC fails the static_assert, while Clang and MSVC accept it.

Apparently `F A::*` becomes `void(A::*)()`, without `&`. Same happens for `&&`.

[Bug c++/105967] Forming a pointer to ref-qualified member function using a function typedef ignores the qualifier

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105967

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Note it looks like the pointer to member function type is where it loses the
ref-qualifer and not earlier.
That is GCC correctly rejects:
    using F = void() &; 
    F t;

[Bug c++/105967] Forming a pointer to ref-qualified member function using a function typedef ignores the qualifier

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105967

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW
      Known to fail|                            |4.8.1, 5.1.0
   Last reconfirmed|                            |2022-06-14

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
here is a testcase without using static_assert:
    struct A {void g()&;};
    using F = void() &; 
    F A::* t = &A::g;

Confirmed. Not a regression.