[Bug c/125261] _Generic -Wuseless-cast false positive

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=125261

--- Comment #10 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Martin Uecker <uecker@gcc.gnu.org>:

https://gcc.gnu.org/g:dee30fc0e980ee26a804a74da74decc0cea10b8f

commit r17-483-gdee30fc0e980ee26a804a74da74decc0cea10b8f
Author: Martin Uecker <uecker@tugraz.at>
Date:   Tue May 12 07:11:38 2026 +0200

    c: avoid false positive for useless casts and generic [PR125261]

    To reduce the number of false positives, we guard -Wuseless-cast by
    c_inhibit_evaluation_warnings and also increment it for a generic
    association if we have seen a prior match for a (non-default)
    association.  This covers the common case where the default association
    comes last.  If there is another association selected after we have
    seen a default, we still have false positives.

            PR c/125261

    gcc/c/ChangeLog:
            * c-parser.cc (c_parser_generic_selection): Modify logic for
            c_inhibit_evaluation_warnings.
            * c-typeck.cc (build_c_cast): Use c_inhibit_evaluation_warnings.

    gcc/testsuite/ChangeLog:
            * gcc.dg/pr125261.c: New test.