[Bug c/124303] C23: redeclaration of struct with function pointer with const pointer to struct as argument

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=124303

--- Comment #7 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-16 branch has been updated by Martin Uecker
<uecker@gcc.gnu.org>:

https://gcc.gnu.org/g:beca4454ff9990d8fa1ba4e7c30b18af0e6cca2b

commit r16-9089-gbeca4454ff9990d8fa1ba4e7c30b18af0e6cca2b
Author: Martin Uecker <uecker@tugraz.at>
Date:   Sat Feb 28 17:12:43 2026 +0100

    c: Fix recursive structure / union redeclaration with qualifiers [PR124303]

    We reject correct recursive redeclarations when qualifiers are involved.
    The reason is that the check is done before the variants are completed.

            PR c/124303

    gcc/c/ChangeLog:
            * c-decl.cc (finish_struct): Check for consistency of
            declarations after completing variants.

    gcc/testsuite/ChangeLog:
            * gcc.dg/pr124303.c: New test.

    (cherry picked from commit 7c3e6df8ae01a473fba63e12efe2c82bd50ad502)