[Bug c++/82613] Cannot access private definitions in base clause of friend class template

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82613

--- Comment #3 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Patrick Palka <ppalka@gcc.gnu.org>:

https://gcc.gnu.org/g:79e1251b642db038df276153c9f2ec6b82e56162

commit r11-6815-g79e1251b642db038df276153c9f2ec6b82e56162
Author: Patrick Palka <ppalka@redhat.com>
Date:   Wed Jan 20 09:43:48 2021 -0500

    c++: Defer access checking when processing bases [PR82613]

    When parsing the base-clause of a class declaration, we need to defer
    access checking until the entire base-clause has been seen, so that
    access can be properly checked relative to the scope of the class with
    all its bases attached.  This allows us to accept the declaration of
    struct D from Example 2 of [class.access.general] (access12.C below).

    Similarly when substituting into the base-clause of a class template,
    which is the subject of PR82613.

    gcc/cp/ChangeLog:

            PR c++/82613
            * parser.c (cp_parser_class_head): Defer access checking when
            parsing the base-clause until all bases are seen and attached
            to the class type.
            * pt.c (instantiate_class_template): Likewise when substituting
            into dependent bases.

    gcc/testsuite/ChangeLog:

            PR c++/82613
            * g++.dg/parse/access12.C: New test.
            * g++.dg/template/access35.C: New test.