[Bug c++/115425] [13/14/15 regression] ICE: tree check: expected type_pack_expansion or expr_pack_expansion, have error_mark in tsubst_pack_expansion, at cp/pt.cc:13778

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115425

--- Comment #4 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The trunk branch has been updated by Marek Polacek <mpola...@gcc.gnu.org>:

https://gcc.gnu.org/g:ed6ffc4e62f716d1b31d599d22594dd969da137f

commit r15-1621-ged6ffc4e62f716d1b31d599d22594dd969da137f
Author: Marek Polacek <pola...@redhat.com>
Date:   Fri Jun 14 17:50:29 2024 -0400

    c++: ICE with generic lambda and pack expansion [PR115425]

    In r13-272 we hardened the *_PACK_EXPANSION and *_ARGUMENT_PACK macros.
    That trips up here because make_pack_expansion returns error_mark_node
    and we access that with PACK_EXPANSION_LOCAL_P.

            PR c++/115425

    gcc/cp/ChangeLog:

            * pt.cc (tsubst_pack_expansion): Return error_mark_node if
            make_pack_expansion doesn't work out.

    gcc/testsuite/ChangeLog:

            * g++.dg/cpp2a/lambda-generic12.C: New test.