[Bug libstdc++/92156] Cannot in-place construct std::any with std::any

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92156

--- Comment #4 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Jonathan Wakely <redi@gcc.gnu.org>:

https://gcc.gnu.org/g:d1462b0782555354b4480e1f46498586d5882972

commit r10-7935-gd1462b0782555354b4480e1f46498586d5882972
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Fri Apr 24 00:54:20 2020 +0100

    libstdc++: Fix constructor constraints for std::any  (PR 90415)

    This removes a non-standard extension to std::any which causes errors
    for valid code, due to recursive instantiation of a trait that isn't
    supposed to be in the constraints.

    It also removes some incorrect constraints on the in_place_type<T>
    constructors and emplace members, which were preventing creating a
    std::any object with another std::any as the contained value.

    2020-04-24  Kamlesh Kumar  <kamleshbhalui@gmail.com>
                Jonathan Wakely  <jwakely@redhat.com>

            PR libstdc++/90415
            PR libstdc++/92156
            * include/std/any (any): Rename template parameters for consistency
            with the standard.
            (any::_Decay): Rename to _Decay_if_not_any.
            (any::any(T&&):: Remove is_constructible from constraints. Remove
            non-standard overload.
            (any::any(in_place_type_t<T>, Args&&...))
            (any::any(in_place_type_t<T>, initializer_list<U>, Args&&...))
            (any::emplace(Args&&...))
            (any::emplace(initializer_list<U>, Args&&...)):
            Use decay_t instead of _Decay.
            * testsuite/20_util/any/cons/90415.cc: New test.
            * testsuite/20_util/any/cons/92156.cc: New Test.
            * testsuite/20_util/any/misc/any_cast_neg.cc: Make dg-error
directives
            more robust.
            * testsuite/20_util/any/modifiers/92156.cc: New test.