[Bug c++/85790] c++17 - Access control issue with template argument deduction

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85790

--- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Fixed by r12-926

    c++: implicit deduction guides, protected access

    Jonathan raised this issue with CWG, and there seems to be general
agreement
    that a deduction guide generated from a constructor should have access to
    the same names that the constructor has access to.  That seems to be as
easy
    as setting DECL_CONTEXT.

    gcc/cp/ChangeLog:

            * pt.c (build_deduction_guide): Treat the implicit deduction guide
            as a member of the class.

    gcc/testsuite/ChangeLog:

            * g++.dg/cpp1z/class-deduction-access1.C: New test.
            * g++.dg/cpp1z/class-deduction-access2.C: New test.