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From: "dcb314 at hotmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/109031] csmith: possible bad code with -O2
 -fno-strict-aliasing
Date: Thu, 09 Mar 2023 09:25:04 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D109031

David Binderman <dcb314 at hotmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|RESOLVED                    |UNCONFIRMED
         Resolution|INVALID                     |---

--- Comment #22 from David Binderman <dcb314 at hotmail dot com> ---
(In reply to Jakub Jelinek from comment #20)
> trying to ensure the reduction doesn't introduce uninitialized var uses
> which weren't there before=20

I was also thinking this myself, so I went back to the original
test case I reported, before any reduction. This is what I found:

$ for i in ~/gcc/results.202205*/bin/gcc; do echo $i; $i -w
-ftrivial-auto-var-init=3Dzero -O2 -fno-strict-aliasing bug892.c && (./a.ou=
t 1 |
fgrep g_50); done
/home/dcb36/gcc/results.20220501/bin/gcc
...checksum after hashing g_50 : 646CF84D
/home/dcb36/gcc/results.20220508/bin/gcc
...checksum after hashing g_50 : 646CF84D
/home/dcb36/gcc/results.20220515/bin/gcc
...checksum after hashing g_50 : C21BF3F9
$=20

So the original bug is still there and my reduction looks invalid ;-|

Snapshots don't exist between 20220508 and 20220515. Is anyone else
able to bisect that range ?=