Return-path: Received: from mail-pb0-f47.google.com ([209.85.160.47]:52914 "EHLO mail-pb0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756347Ab3LaT2j (ORCPT ); Tue, 31 Dec 2013 14:28:39 -0500 Message-ID: <52C31AE4.1050501@lwfinger.net> (sfid-20131231_202857_283473_995CF50E) Date: Tue, 31 Dec 2013 13:28:36 -0600 From: Larry Finger MIME-Version: 1.0 To: Mark Cave-Ayland CC: linux-wireless , Geert Uytterhoeven , LKML Subject: Re: Question on compiler warning References: <52C21CE3.3020402@lwfinger.net> <52C2A2E5.3020100@ilande.co.uk> In-Reply-To: <52C2A2E5.3020100@ilande.co.uk> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Sender: linux-wireless-owner@vger.kernel.org List-ID: 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