[Bug c/120381] [14/15/16 Regression] internal compiler error: in composite_type_internal, at c/c-typeck.cc:848

[cvs-commit at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120381

--- Comment #6 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Martin Uecker <uec...@gcc.gnu.org>:

https://gcc.gnu.org/g:0e0f963bcfbfce351dd4aad82e6dbc6fc84a0724

commit r16-982-g0e0f963bcfbfce351dd4aad82e6dbc6fc84a0724
Author: Martin Uecker <uec...@tugraz.at>
Date:   Thu May 29 19:13:46 2025 +0200

    c: fix ICE for mutually recursive structures [PR120381]

    For invalid nesting of a structure definition in a definition
    of itself or when using a rather obscure construction using statement
    expressions, we can create mutually recursive pairs of non-identical
    but compatible structure types.  This can lead to invalid composite
    types and an ICE.  If we detect recursion even for swapped pairs
    when forming composite types, this is avoided.

            PR c/120381

    gcc/c/ChangeLog:
            * c-typeck.cc (composite_type_internal): Stop recursion for
            swapped pairs.

    gcc/testsuite/ChangeLog:
            * gcc.dg/pr120381.c: New test.
            * gcc.dg/gnu23-tag-composite-6.c: New test.