From: "H. Peter Anvin" <hpa@zytor.com>
To: Petr Tesarik <ptesarik@suse.cz>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>,
LKML <linux-kernel@vger.kernel.org>
Subject: Re: Definition of BUG on x86
Date: Thu, 19 Feb 2009 10:38:31 -0800 [thread overview]
Message-ID: <499DA727.2060606@zytor.com> (raw)
In-Reply-To: <1235043648.15053.35.camel@nathan.suse.cz>
Petr Tesarik wrote:
>
> Ah, yes, you're right. If you want to make gcc aware of the fact that a
> function never returns, it must recognize that there is no path to that
> function's EXIT, otherwise it will emit a warning (which is pretty
> annoying, indeed). Since we don't want to make a call/jmp to an external
> noreturn function, so the no-return code must be directly visible to
> gcc. Unfortunately, there is no way of telling gcc that an asm statement
> does not return.
>
At Transmeta, we had an internal hack to gcc that added
__builtin_not_reached(); for this particular reason. This would
probably be the best way to handle this.
-hpa
--
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel. I don't speak on their behalf.
prev parent reply other threads:[~2009-02-19 18:42 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <1234975856.15053.16.camel@nathan.suse.cz>
[not found] ` <499C4786.5010504@goop.org>
2009-02-19 11:40 ` Definition of BUG on x86 Petr Tesarik
2009-02-19 12:10 ` Ingo Molnar
2009-02-19 12:19 ` Petr Tesarik
2009-02-19 12:22 ` Ingo Molnar
2009-02-19 12:38 ` Petr Tesarik
2009-02-19 12:47 ` Ingo Molnar
2009-02-19 13:02 ` Petr Tesarik
2009-02-19 14:49 ` Ingo Molnar
2009-02-19 15:32 ` Jeremy Fitzhardinge
2009-02-19 15:35 ` Ingo Molnar
2009-02-19 16:11 ` Petr Tesarik
2009-02-19 16:16 ` Ingo Molnar
2009-02-19 16:34 ` Jeremy Fitzhardinge
2009-02-19 16:41 ` Ingo Molnar
2009-02-19 20:07 ` H. Peter Anvin
2009-02-19 20:26 ` Ingo Molnar
2009-02-19 16:55 ` Petr Tesarik
2009-02-19 16:32 ` Jeremy Fitzhardinge
2009-02-19 18:38 ` H. Peter Anvin [this message]
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