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

[Jakub Jelinek]

On Wed, Jul 29, 2026 at 04:58:59PM +0100, Jonathan Wakely wrote:
> 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.

LGTM, thanks.

	Jakub