[Bug bootstrap/103459] Make configury regenerate cleanly with `autoreconf -Wall`

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103459

--- Comment #13 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The trunk branch has been updated by Pietro Monteiro <pietro@gcc.gnu.org>:

https://gcc.gnu.org/g:0623f27940353f4cf6da1cccf8a37637a4febecc

commit r17-1852-g0623f27940353f4cf6da1cccf8a37637a4febecc
Author: Pietro Monteiro <pietro@sociotechnical.xyz>
Date:   Thu Jun 25 08:29:18 2026 -0400

    libstdc++: Update AC_FOREACH to m4_foreach_w [PR103459]

    AC_FOREACH has been deprecated by Autoconf.  Update to
    m4_foreach_w.  No changes to generated files.

            PR bootstrap/103459

    libstdc++-v3/ChangeLog:

            * configure.ac: Update AC_FOREACH to m4_foreach_w.

    Signed-off-by: Pietro Monteiro <pietro@sociotechnical.xyz>