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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug sanitizer/114217] -fsanitize=alignment false positive with intended unaligned struct member access
Date: Sun, 03 Mar 2024 07:10:30 +0000	[thread overview]
Message-ID: <bug-114217-4-u4SYCk5dTQ@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-114217-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114217

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

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

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
>but also emits code to assert alignment.


Yes because the code is broken still.

The alignment is not about when the access happens but rather when the pointer
is casted to.

So in this case when passing in the argument to f, the argument entry should be
aligned to what the `struct dir_entry` is aligned to; otherwise it is undefined
code.

  reply	other threads:[~2024-03-03  7:10 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-03-03  7:03 [Bug sanitizer/114217] New: " akihiko.odaki at daynix dot com
2024-03-03  7:10 ` pinskia at gcc dot gnu.org [this message]
2024-03-03  7:15 ` [Bug sanitizer/114217] " pinskia at gcc dot gnu.org
2024-03-03  7:19 ` akihiko.odaki at daynix dot com
2024-03-03  7:22 ` pinskia at gcc dot gnu.org
2024-03-03  7:29 ` akihiko.odaki at daynix dot com
2024-03-03  7:46 ` akihiko.odaki at daynix dot com
2024-03-03 19:01 ` jakub at gcc dot gnu.org
2024-03-04  5:26 ` akihiko.odaki at daynix dot com
2024-03-04  7:46 ` jakub at gcc dot gnu.org
2024-03-04  7:54 ` jakub at gcc dot gnu.org
2024-03-04  8:11 ` akihiko.odaki at daynix dot com
2024-03-04  8:35 ` jakub at gcc dot gnu.org
2024-03-04  8:45 ` akihiko.odaki at daynix dot com
2024-03-04 21:48 ` i at maskray dot me

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