From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_NEOMUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6F1E7ECE566 for ; Fri, 21 Sep 2018 14:27:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0BFB621550 for ; Fri, 21 Sep 2018 14:27:17 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0BFB621550 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=bootlin.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389991AbeIUUQX (ORCPT ); Fri, 21 Sep 2018 16:16:23 -0400 Received: from mail.bootlin.com ([62.4.15.54]:41476 "EHLO mail.bootlin.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728365AbeIUUQX (ORCPT ); Fri, 21 Sep 2018 16:16:23 -0400 Received: by mail.bootlin.com (Postfix, from userid 110) id 22BCE20901; Fri, 21 Sep 2018 16:27:13 +0200 (CEST) Received: from localhost (AAubervilliers-681-1-42-80.w90-88.abo.wanadoo.fr [90.88.160.80]) by mail.bootlin.com (Postfix) with ESMTPSA id D5456204AE; Fri, 21 Sep 2018 16:26:53 +0200 (CEST) Date: Fri, 21 Sep 2018 16:26:54 +0200 From: Maxime Ripard To: zhong jiang Cc: airlied@linux.ie, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] drm: sun4i: Fix a uninitialized variable warning. Message-ID: <20180921142654.ahuhswypvscjsuyj@flea> References: <1537255520-41614-1-git-send-email-zhongjiang@huawei.com> <20180919084719.6ymf6h4eftomfab3@flea> <5BA2106C.2080007@huawei.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="ayc3oltgnjlkh76l" Content-Disposition: inline In-Reply-To: <5BA2106C.2080007@huawei.com> User-Agent: NeoMutt/20180716 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --ayc3oltgnjlkh76l Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Sep 19, 2018 at 05:01:32PM +0800, zhong jiang wrote: > On 2018/9/19 16:47, Maxime Ripard wrote: > > On Tue, Sep 18, 2018 at 03:25:20PM +0800, zhong jiang wrote: > >> Fix the following compile warning: > >> > >> drivers/gpu/drm/sun4i/sun4i_tcon.c:1088: warning: 'has_lvds_alt' may b= e used uninitialized in this function [-Wmaybe-uninitialized] > >> bool has_lvds_rst, has_lvds_alt, can_lvds; > >> > >> Signed-off-by: zhong jiang > > I can't see any code path that would lead to an uninitialized usage of > > that variable. > > > > Which compiler produced that warning? I tried building it today with > > gcc 8.1.1, and I don't see that warning either. > > I indeed hit the issue. the gcc version is > gcc (Ubuntu 5.4.0-6ubuntu1~16.04.9) 5.4.0 20160609 I've tested with 4.* gcc, and it didn't report any error. It seems to be a false positive for this particular version, so there's no need to merge that patch. If more people are affected, we'll obviously do something about it though. Thanks! Maxime --=20 Maxime Ripard, Bootlin Embedded Linux and Kernel engineering https://bootlin.com --ayc3oltgnjlkh76l Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEE0VqZU19dR2zEVaqr0rTAlCFNr3QFAluk/60ACgkQ0rTAlCFN r3TacQ//bSkkQxX7E4oJAxcF8drs6U518u9hj56SRGi/1OvPryJOC5C6C05lFaju 24Yr/qAa0drigSn7HAWqNZ8jXpHl1L2ckAwXxAbwoiq0LWGcylLr5KpDuvB7UauP 9tmir0ioLDJgm8U84CX8bHBzveYtScEkNJtiURCqc5B6S01L9NgCGI9Kn1D8yNDm vgLS4rBK+Si3HAVFk8sNfegI5mV6LRD4ktHmz6taaG4U+QwGcboEd5J8Iei4PNpv 1BP/KVNWjThWOr5KvOZSdDex21kriAarmgtjXNxKl7ZIk3mrFOfb/UQJmMYZzY7k QwaVHMGMnCWWRC6LWGlCAvXtII52GJ34LYUxCQIzk0I0aojd/1gO5BSh1+UdrGMC 3Qi8Nuk1bydued8M/dbUFwRBO09LpQKjNFIasz5nBeizls77J5wWM2g+3b8lLljn 04f6DX0RGQ77MINx37T0qVq9mpiJVbfw+1FJAyQwGKheA4G9FvmpPb6WB5icGF35 PBasmd/ummaw7bTeVS+cpey1suu1039BSLUcf26ugYlJsirRzegOHEzYAT29gSwv I8OemphfVific8+4mHIVJ9wxQCFKKlo1zu7yBrgUQjQaiGfqMV+ZQDJes+ETnl7Q SIXGlgFbN7jhgTme+VT+rAKe9IIlzAHSG9uOgrIdlxL8eb4OXbE= =5SCw -----END PGP SIGNATURE----- --ayc3oltgnjlkh76l--