This is an unofficial snapshot of the ISO/IEC JTC1 SC22 WG21 Core Issues List revision 120a. See http://www.open-std.org/jtc1/sc22/wg21/ for the official list.

2026-06-10

3166. Protected access rule for a pointer-to-member from a reflect-expression

(From submission #852.)

Consider:

  class A {
  protected:
    void f();
  };

  struct B : A {
    static constexpr auto r = ^^A::f;
  };

Do the restrictions in 11.8.5 [class.protected] on the use of expression &A::f apply to the reflect-expression?

Suggested resolution [SUPERSEDED]:

Change in 7.6.2.10 [expr.reflect] bullet 7.2 as follows:

A reflect-expression R of the form ^^id-expression represents an entity determined as follows:

• ...
• Otherwise, if the id-expression denotes an overload set S, overload resolution for the expression &S with no target shall select a unique function (12.3 [over.over]) the expression &id-expression shall be well-formed when considered as an unevaluated operand; R represents that the function selected by overload resolution (12.3 [over.over]).

CWG 2026-05-08

Reflection supports deleted functions, but the phrasing above does not.

Proposed resolution (approved by CWG 2026-05-19):

Change in 7.6.2.10 [expr.reflect] bullet 7.2 as follows:

A reflect-expression R of the form ^^id-expression represents an entity determined as follows:

• ...
• Otherwise, if the id-expression denotes an overload set S, overload resolution for the expression &S with no target shall select a unique function (12.3 [over.over]) the expression &id-expression shall be well-formed when considered as an unevaluated operand, except that the function F selected as described in 12.3 [over.over] may be deleted (9.6.3 [dcl.fct.def.delete]); R represents that function F .