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From: "slyfox at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/111009] [12/13/14 regression] -fno-strict-overflow erroneously elides null pointer checks and causes SIGSEGV on perf from linux-6.4.10
Date: Wed, 16 Aug 2023 21:24:06 +0000	[thread overview]
Message-ID: <bug-111009-4-tg61D4tbCN@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-111009-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111009

--- Comment #9 from Sergei Trofimovich <slyfox at gcc dot gnu.org> ---
Created attachment 55744
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=55744&action=edit
bug.S

At the hazard of stating the obvious: it's a wrong-code when you execute it
(not a gcc ICE).

Should fail on vanilla x86_64-linux-gnu. Tested on today's
r14-3254-g9ade70bb86c874 as:

    $ gcc -Bgcc bug.c.c -fno-strict-overflow -O3 -o bug && ./bug
    Segmentation fault (core dumped)

I also uploaded bug.S as an output of

    $ gcc -Bgcc bug.c.c -fno-strict-overflow -O3 -S -fverbose-asm -o bug.S

if it helps you to find why your output is different.

  parent reply	other threads:[~2023-08-16 21:24 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-08-14  8:26 [Bug middle-end/111009] New: " slyfox at gcc dot gnu.org
2023-08-14  9:34 ` [Bug middle-end/111009] " amonakov at gcc dot gnu.org
2023-08-14 11:34 ` rguenth at gcc dot gnu.org
2023-08-14 11:48 ` rguenth at gcc dot gnu.org
2023-08-15 17:57 ` amacleod at redhat dot com
2023-08-16 20:14 ` slyfox at gcc dot gnu.org
2023-08-16 20:21 ` sjames at gcc dot gnu.org
2023-08-16 20:40 ` slyfox at gcc dot gnu.org
2023-08-16 21:05 ` amacleod at redhat dot com
2023-08-16 21:24 ` slyfox at gcc dot gnu.org [this message]
2023-08-17 15:37 ` amacleod at redhat dot com
2023-08-17 17:39 ` cvs-commit at gcc dot gnu.org
2023-08-17 19:44 ` slyfox at gcc dot gnu.org
2024-05-08 12:03 ` [Bug middle-end/111009] [12/13 " rguenth at gcc dot gnu.org
2024-05-08 18:26 ` amacleod at redhat dot com
2024-05-09 14:32 ` cvs-commit at gcc dot gnu.org
2024-05-10  6:36 ` [Bug middle-end/111009] [12 " rguenth at gcc dot gnu.org
2024-05-13 17:49 ` cvs-commit at gcc dot gnu.org
2024-06-12 11:38 ` rguenth at gcc dot gnu.org

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