From: Florian Weimer <fweimer@redhat.com>
To: Adrian Moreno via Gcc-help <gcc-help@gcc.gnu.org>
Cc: David Brown <david.brown@hesbynett.no>,
Stefan Ring <stefanrin@gmail.com>,
Adrian Moreno <amorenoz@redhat.com>
Subject: Re: broken code only when optimized "-O2"
Date: Wed, 22 Dec 2021 11:27:36 +0100 [thread overview]
Message-ID: <877dbx7x47.fsf@oldenburg.str.redhat.com> (raw)
In-Reply-To: <9b28799e-71f8-2ef9-1cc9-01345993cc11@redhat.com> (Adrian Moreno via Gcc-help's message of "Wed, 22 Dec 2021 10:24:28 +0100")
* Adrian Moreno via Gcc-help:
> So here I do not know what the compiler would think about "pos" if it
> happens to point to some invalid stack address.
In such cases, the compiler typically assumes that the code in question
is never executed. This means that the comparison does not need to be
performed, among other things.
Thanks,
Florian
next prev parent reply other threads:[~2021-12-22 10:27 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-12-21 15:40 Adrian Moreno
2021-12-21 16:05 ` Stefan Ring
2021-12-21 16:13 ` Adrian Moreno
2021-12-21 16:39 ` Segher Boessenkool
2021-12-21 17:05 ` David Brown
2021-12-22 9:24 ` Adrian Moreno
2021-12-22 10:27 ` Florian Weimer [this message]
2021-12-22 10:34 ` Adrian Moreno
2021-12-22 10:36 ` Xi Ruoyao
2021-12-22 16:05 ` Adrian Moreno
2021-12-22 15:32 ` LIU Hao
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