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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/106902] [11/12/13 Regression] Program compiled with -O3
 -mfma produces different result
Date: Tue, 13 Sep 2022 07:06:45 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D106902

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[11/12 Regression] Program  |[11/12/13 Regression]
                   |compiled with -O3 -mfma     |Program compiled with -O3
                   |produces different result   |-mfma produces different
                   |                            |result
             Blocks|                            |53947

--- Comment #5 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to Martin Li=C5=A1ka from comment #4)
> Fixed on master with r13-1450-gd2a898666609452e.
> Started with r11-4637-gf5e18dd9c7dacc96.

I believe both a are unrelated.  The fix possibly caused a missed optimizat=
ion
while the cause exposed some opportunity.

More analysis is needed here.


Referenced Bugs:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D53947
[Bug 53947] [meta-bug] vectorizer missed-optimizations=