[Bug libstdc++/121827] ext/pointer.h can't be included alone and ext/cast.h shouldn't be included in extc++.h

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121827

--- Comment #5 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-13 branch has been updated by Jakub Jelinek
<jakub@gcc.gnu.org>:

https://gcc.gnu.org/g:f38a98a1c07305a0ff95c076973611485767a02c

commit r13-10167-gf38a98a1c07305a0ff95c076973611485767a02c
Author: Jakub Jelinek <jakub@redhat.com>
Date:   Mon Sep 8 11:49:58 2025 +0200

    libstdc++: Fix up <ext/pointer.h> [PR121827]

    During the tests mentioned in
    https://gcc.gnu.org/pipermail/gcc-patches/2025-August/692482.html
    (but dunno why I haven't noticed it back in August but only when testing
    https://gcc.gnu.org/pipermail/gcc-patches/2025-September/694527.html )
    I've noticed two ext header problems.
    One is that #include <ext/pointer.h> got broken with the
    r13-3037-g18f176d0b25591e28 change and since then is no longer
    self-contained, as it includes iosfwd only if _GLIBCXX_HOSTED is defined
    but doesn't actually include bits/c++config.h to make sure it is defined,
    then includes a bunch of headers which do include bits/c++config.h and
    finally uses in #if _GLIBCXX_HOSTED guarded code what is declared in
iosfwd.
    The other problem is that ext/cast.h is also not a self-contained header,
    but that one has
    /** @file ext/cast.h
     *  This is an internal header file, included by other library headers.
     *  Do not attempt to use it directly. @headername{ext/pointer.h}
     */
    comment, so I think we just shouldn't include it in extc++.h and let
    ext/pointer.h include it.

    2025-09-08  Jakub Jelinek  <jakub@redhat.com>

            PR libstdc++/121827
            * include/precompiled/extc++.h: Don't include ext/cast.h which is
an
            internal header.
            * include/ext/pointer.h: Include bits/c++config.h before
            #if _GLIBCXX_HOSTED.

    (cherry picked from commit 592bafb26eb1fd50979f6cdf2176897c4a02c281)