linux-kernel - Re: Question on compiler warning

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Tue, 31 Dec 2013 13:28:36 -0600
From:	Larry Finger <Larry.Finger@...inger.net>
To:	Mark Cave-Ayland <mark.cave-ayland@...nde.co.uk>
CC:	linux-wireless <linux-wireless@...r.kernel.org>,
	Geert Uytterhoeven <geert@...ux-m68k.org>,
	LKML <linux-kernel@...r.kernel.org>
Subject: Re: Question on compiler warning

On 12/31/2013 04:56 AM, Mark Cave-Ayland wrote:
> Hi Larry,
>
> Could it be that you don't see the issue the locally because you've got
> different compiler optimisation settings? I've seen a similar bug recently on
> another project where the "may be used uninitialized" warning appears with -O0
> and -O1 but magically disappears with the default -O2 setting (presumably
> because the optimiser performs some kind of inlining/reordering that makes the
> issue go away).

Mark,

It is possible. Certainly, a higher optimization level will force the compiler 
to do a better job of flow analysis. I am using -O2, which is the standard in 
the kernel makefile. I would expect that Geert is also using the same lever, but 
perhaps not.

Larry


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/