[Bug tree-optimization/94963] [11 Regression] Spurious uninitialized warning for static variable building glibc

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94963

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

https://gcc.gnu.org/g:371905d12259c180efb9b1f1b5716e969feb60f9

commit r11-138-g371905d12259c180efb9b1f1b5716e969feb60f9
Author: Richard Biener <rguent...@suse.de>
Date:   Wed May 6 09:39:45 2020 +0200

    tree-optimization/94963 - avoid bogus uninit warning with store-motion

    Eliding the load for store-motion causes an uninitialized variable
    flowing into the loop, conditionally initialized and used.  The
    uninit warning cannot relate the flag used to guard the initialization
    and use with the actual initialization so the following robustifies
    the previous approach of marking the conditional store as not to
    be warned on by instead initializing the variable on loop entry
    from an uninitialized variable we mark as not to be warned for.

    2020-05-06  Richard Biener  <rguent...@suse.de>

            PR tree-optimization/94963
            * tree-ssa-loop-im.c (execute_sm_if_changed): Remove
            no-warning marking of the conditional store.
            (execute_sm): Instead mark the uninitialized state
            on loop entry to be not warned about.

            * gcc.dg/pr94963.c: New testcase.