[Bug tree-optimization/108625] [11/12 Regression] forwprop introduces new UB

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108625

--- Comment #4 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-12 branch has been updated by Richard Biener
<rguenth@gcc.gnu.org>:

https://gcc.gnu.org/g:e19e9c36abc7fff9c628cf744e55e4c0e686ea53

commit r12-9257-ge19e9c36abc7fff9c628cf744e55e4c0e686ea53
Author: Richard Biener <rguenther@suse.de>
Date:   Thu Feb 2 11:09:26 2023 +0100

    middle-end/108625 - wrong folding due to misinterpreted !

    The following fixes a problem with ! handling in genmatch which isn't
    conservative enough when intermediate simplifications push to the
    sequence but the final operation appears to just pick an existing
    (but in this case newly defined in the sequence) operand.  The easiest
    fix is to disallow adding to the sequence when processing !.

            PR middle-end/108625
            * genmatch.cc (expr::gen_transform): Also disallow resimplification
            from pushing to lseq with force_leaf.
            (dt_simplify::gen_1): Likewise.

            * gcc.dg/pr108625.c: New testcase.

    (cherry picked from commit 605d1297b91c2c7c23ccfe669e66dda5791d1f55)