[Bug c/97125] [11 Regression] new problem with -Wduplicated-branches

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97125

--- Comment #8 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Marek Polacek <mpolacek@gcc.gnu.org>:

https://gcc.gnu.org/g:c48ffe21f8f3478cf08f9442e3f973df358caf2a

commit r11-3397-gc48ffe21f8f3478cf08f9442e3f973df358caf2a
Author: Marek Polacek <polacek@redhat.com>
Date:   Sun Sep 20 16:11:00 2020 -0400

    c: Fix -Wduplicated-branches ICE [PR97125]

    We crash here because since r11-3302 the C FE uses codes like SWITCH_STMT
    in the else branches in the attached test, and inchash::add_expr in
    do_warn_duplicated_branches doesn't handle these front-end codes.  In
    the C++ FE this works because by the time we get to
do_warn_duplicated_branches
    we've already cp_genericize'd the SWITCH_STMT tree into a SWITCH_EXPR.

    The fix is to call do_warn_duplicated_branches_r only after loops and other
    structured control constructs have been lowered.

    gcc/c-family/ChangeLog:

            PR c/97125
            * c-gimplify.c (c_genericize): Only call
do_warn_duplicated_branches_r
            after loops and other structured control constructs have been
lowered.

    gcc/testsuite/ChangeLog:

            PR c/97125
            * c-c++-common/Wduplicated-branches-15.c: New test.