[Bug c++/107179] [11/12/13 Regression] requires-expression gives hard error for inaccessible constructor

["cvs-commit at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107179

--- Comment #2 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:40c34beef620ed13c4113c893ed4335ccc1b8f92

commit r13-3641-g40c34beef620ed13c4113c893ed4335ccc1b8f92
Author: Patrick Palka <ppalka@redhat.com>
Date:   Thu Nov 3 15:35:18 2022 -0400

    c++: requires-expr and access checking [PR107179]

    Like during satisfaction, we also need to avoid deferring access checks
    during substitution of a requires-expr because the outcome of an access
    check can determine the value of the requires-expr.  Otherwise (in
    deferred access checking contexts such as within a base-clause), the
    requires-expr may evaluate to the wrong result, and along the way a
    failed access check may leak out from it into a non-SFINAE context and
    cause a hard error (as in the below testcase).

            PR c++/107179

    gcc/cp/ChangeLog:

            * constraint.cc (tsubst_requires_expr): Make sure we're not
            deferring access checks.

    gcc/testsuite/ChangeLog:

            * g++.dg/cpp2a/concepts-requires31.C: New test.