[Bug tree-optimization/111397] Spurious warning "'({anonymous})' is used uninitialized" when calling a __returns_twice__ function (-Wuninitialized -O2)

["cvs-commit at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111397

--- Comment #3 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Richard Biener <rguenth@gcc.gnu.org>:

https://gcc.gnu.org/g:92ea12ea99fce546772a40b7bbc2ea850db9b1be

commit r14-3916-g92ea12ea99fce546772a40b7bbc2ea850db9b1be
Author: Richard Biener <rguenther@suse.de>
Date:   Wed Sep 13 09:28:34 2023 +0200

    tree-optimization/111397 - missed copy propagation involving abnormal dest

    The following extends the previous enhancement to copy propagation
    involving abnormals.  We can easily replace abnormal uses by not
    abnormal uses and only need to preserve the abnormals in PHI arguments
    flowing in from abnormal edges.  This changes the may_propagate_copy
    argument indicating we are not propagating into a PHI node to indicate
    whether we know we are not propagating into a PHI argument from an
    abnormal PHI instead.

            PR tree-optimization/111397
            * tree-ssa-propagate.cc (may_propagate_copy): Change optional
            argument to specify whether the PHI destination doesn't flow in
            from an abnormal PHI.
            (propagate_value): Adjust.
            * tree-ssa-forwprop.cc (pass_forwprop::execute): Indicate abnormal
            PHI dest.
            * tree-ssa-sccvn.cc (eliminate_dom_walker::before_dom_children):
            Likewise.
            (process_bb): Likewise.

            * gcc.dg/uninit-pr111397.c: New testcase.