From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Borkmann Subject: Re: [PATCH iproute2] ip, route: fix minor compile warning Date: Fri, 18 Dec 2015 10:18:23 +0100 Message-ID: <5673CF5F.1060806@iogearbox.net> References: <20151214155104.GE6555@orbit.nwl.cc> <566EE5F0.9030504@iogearbox.net> <20151217171203.723b4d16@xeon-e3> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Cc: Phil Sutter , netdev@vger.kernel.org To: Stephen Hemminger Return-path: Received: from www62.your-server.de ([213.133.104.62]:60703 "EHLO www62.your-server.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966463AbbLRJS0 (ORCPT ); Fri, 18 Dec 2015 04:18:26 -0500 In-Reply-To: <20151217171203.723b4d16@xeon-e3> Sender: netdev-owner@vger.kernel.org List-ID: On 12/18/2015 02:12 AM, Stephen Hemminger wrote: > On Mon, 14 Dec 2015 16:53:20 +0100 > Daniel Borkmann wrote: > >> On 12/14/2015 04:51 PM, Phil Sutter wrote: >>> On Mon, Dec 14, 2015 at 04:34:29PM +0100, Daniel Borkmann wrote: >>>> Seems like gcc (4.8.3) doesn't catch this false positive, triggering >>>> after 0f7543322c5f ("route: ignore RTAX_HOPLIMIT of value -1"): >>>> >>>> iproute.c: In function 'print_route': >>>> iproute.c:301:12: warning: 'val' may be used uninitialized in this function [-Wmaybe-uninitialized] >>>> features &= ~RTAX_FEATURE_ECN; >>>> ^ >>>> iproute.c:575:10: note: 'val' was declared here >>>> __u32 val; >>>> ^ >>>> So just shut it up by initializing to 0. >>> >>> Hmm. Interestingly, my patch shouldn't have changed anything relevant >>> for gcc's decision. OTOH, I don't see a warning using gcc-4.9.3. >> >> If I revert it, the warning is gone for me ;) perhaps some heuristic issue >> with that gcc version. >> >> Cheers, >> Daniel > > I don't see this warning on current master with gcc 4.9.2. Well, in the commit message I wrote 4.8.3 ... but I don't mind if we drop it, sure.