[Bug libstdc++/126452] Typo in check for --gc-sections support in acinclude.m4

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126452

--- Comment #12 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Jonathan Wakely <[email protected]>:

https://gcc.gnu.org/g:b7ce998a967639b955159eeeae940cb069c518d8

commit r17-2791-gb7ce998a967639b955159eeeae940cb069c518d8
Author: Jonathan Wakely <[email protected]>
Date:   Wed Jul 29 16:55:39 2026 +0100

    libstdc++: Fix grep for linker warning about --gc-sections [PR126452]

    Current versions of GNU ld print "warning" with a lowercase 'w' so
    adjust the grep patter. Also use LC_ALL=C to ensure the warning isn't
    translated.

    Because m4 uses square brackets as quotes, we need to use double
    brackets in the grep pattern to expand to "[Ww]" in the configure
    script.

    libstdc++-v3/ChangeLog:

            PR libstdc++/126452
            * acinclude.m4 (GLIBCXX_CHECK_LINKER_FEATURES): Use LC_ALL_C and
            match both "Warning" and "warning" in ld output.
            * configure: Regenerate.

    Reviewed-by: Jakub Jelinek <[email protected]>