From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by dpdk.org (Postfix) with ESMTP id A269E2BEA for ; Fri, 11 Mar 2016 10:23:40 +0100 (CET) Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga103.fm.intel.com with ESMTP; 11 Mar 2016 01:23:33 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.24,320,1455004800"; d="scan'208";a="64168653" Received: from rhorton-mobl.ger.corp.intel.com (HELO [163.33.229.61]) ([163.33.229.61]) by fmsmga004.fm.intel.com with ESMTP; 11 Mar 2016 01:22:20 -0800 Message-ID: <56E28E4C.20502@intel.com> Date: Fri, 11 Mar 2016 09:22:20 +0000 From: Remy Horton Organization: Intel Shannon Limited User-Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: Panu Matilainen , dev@dpdk.org References: <1456426121-21423-1-git-send-email-aconole@redhat.com> <1456426121-21423-9-git-send-email-aconole@redhat.com> <56E179E2.1020704@redhat.com> <56E18894.6020409@intel.com> <56E18CA5.4090200@redhat.com> In-Reply-To: <56E18CA5.4090200@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [dpdk-dev] [PATCH 8/8] drivers/net/ixgbe: Fix uninitialized warning X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 11 Mar 2016 09:23:41 -0000 On 10/03/2016 15:03, Panu Matilainen wrote: > On 03/10/2016 04:45 PM, Remy Horton wrote: [...] >> In two minds about this. It is a logical impossibility, but these days >> optimising compilers are getting very aggressive. For instance GCC has a >> delightfully-named -fdelete-null-pointer-checks option, which caused >> security holes.. > > Indeed, that's why silencing a false positive (assuming it actually is > one) by throwing some more NULL-checks for the allegedly impossible > makes me a bit nervous. Besides compiler optimizations going crazy, I've > seen such extra NULL-checks turn into actual bugs when surroundings > subtly change. It cuts both ways. To anyone who is not an active compiler engineer, fixing a warning being /more/ likley to screw things up is quite a big thing. Do we want to turn off warnings or turn off optimisations.. :) ..Remy