From: Alan Modra <amodra@gmail.com>
To: Jan Beulich <jbeulich@suse.com>
Cc: binutils@sourceware.org, "H.J. Lu" <hjl.tools@gmail.com>
Subject: Re: strange segfault i386-dis.c:9815:28
Date: Mon, 20 Mar 2023 20:56:26 +1030 [thread overview]
Message-ID: <ZBg00h4pCd1bItto@squeak.grove.modra.org> (raw)
In-Reply-To: <ZBgR4F2jhv1stvhD@squeak.grove.modra.org>
On Mon, Mar 20, 2023 at 06:27:20PM +1030, Alan Modra wrote:
> On Mon, Mar 20, 2023 at 08:29:44AM +0100, Jan Beulich wrote:
> > Does this actually go far enough? Functions called may be inlined, and
> > hence further accesses of struct fields held in registers may occur.
>
> I think we are OK. The fields accessed are ins.address_mode and
> ins.info, which are set up early in print_insn and read-only past the
> setjmp.
Perhaps you are correct that my change doesn't go far enough for a
different reason. Accessing these local var structs using a volatile
qualified pointer may indeed read the object, but I don't think
changed values are guaranteed to be written back to the object unless
the actual object is declared volatile.
I'm going to revert my change. It didn't cure the oss-fuzz testcase
fails.
--
Alan Modra
Australia Development Lab, IBM
next prev parent reply other threads:[~2023-03-20 10:26 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-03-17 10:41 Alan Modra
2023-03-17 15:56 ` H.J. Lu
2023-03-17 17:09 ` Andreas Schwab
2023-03-19 22:44 ` Alan Modra
2023-03-20 7:29 ` Jan Beulich
2023-03-20 7:57 ` Alan Modra
2023-03-20 10:26 ` Alan Modra [this message]
2023-03-20 10:41 ` Jan Beulich
2023-03-23 12:59 ` Alan Modra
2023-04-04 7:03 ` Jan Beulich
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