From patchwork Mon Jan 25 15:32:45 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 101130 Delivered-To: patch@linaro.org Received: by 10.112.130.2 with SMTP id oa2csp1427422lbb; Mon, 25 Jan 2016 07:34:18 -0800 (PST) X-Received: by 10.98.93.195 with SMTP id n64mr26770153pfj.67.1453736058608; Mon, 25 Jan 2016 07:34:18 -0800 (PST) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id s1si34301648pfa.149.2016.01.25.07.34.18; Mon, 25 Jan 2016 07:34:18 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757456AbcAYPeQ (ORCPT + 30 others); Mon, 25 Jan 2016 10:34:16 -0500 Received: from mout.kundenserver.de ([217.72.192.74]:59321 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751758AbcAYPeP (ORCPT ); Mon, 25 Jan 2016 10:34:15 -0500 Received: from wuerfel.lan. ([78.42.132.4]) by mrelayeu.kundenserver.de (mreue102) with ESMTPA (Nemesis) id 0MZUYX-1age6p0rhF-00LFlA; Mon, 25 Jan 2016 16:33:46 +0100 From: Arnd Bergmann To: Steven Whitehouse , Bob Peterson Cc: linux-arm-kernel@lists.infradead.org, Arnd Bergmann , cluster-devel@redhat.com, linux-kernel@vger.kernel.org Subject: [PATCH] gfs2: avoid uninitialized variable warning Date: Mon, 25 Jan 2016 16:32:45 +0100 Message-Id: <1453735996-1958733-2-git-send-email-arnd@arndb.de> X-Mailer: git-send-email 2.7.0 In-Reply-To: <1453735996-1958733-1-git-send-email-arnd@arndb.de> References: <1453735996-1958733-1-git-send-email-arnd@arndb.de> X-Provags-ID: V03:K0:HORaNShL7jODk2iZjMZvPVUbYiCwNHK7nsEsSPkAvLKdpAMCY86 NOE2y4tnrLldW6BzLcnFPKktENMB9iJFpUB9/I4qy51jPpVUSubNcowDmPRRvY3fuGiO3w6 XA/rOVxRd6XZ8YuhlpFLWDss9stR6IHCRAJ9N8zLvfFq1wQRWvrEvsS+L1EF43V6awcKrtz 8+NB/CUg5Gy/2Jo5gUIWw== X-UI-Out-Filterresults: notjunk:1; V01:K0:scBya7jFPgQ=:z21k9pnzo7OdtiwaoBxbZq 4VSbnxQzfK85iN5CFcVfOCGM6lz1T1JhXUi3Q4QY8kcJ2M1WPInfAPATgflwIouUs5K2Xol7T Nq+um1pa8wr0UUcn43SDHG++et3hXHgb533PNSv/6YxI+rXTw27NaKADQ2hjQHV7vjKN9IZYr +JOhYM5yGUh3Xun/RV2JsPydBWIzLwZEy+O8aQlXGGtZikt7w00UmYfoXt4nM3qAMATyQjhpx K2VhcspJ0IxB2b6iDmCjMhhzSyILHVcojNcHu+D2VDU7wA5QnHzqDQ8uimWqzamkFuhvIt/ks +S/rIDuCRYthNGhFUdys6JiuQMTOrMWz/ATaTwsr72EDu93OjvHyJ1+innkDxFivUxD/qMBL2 dNdr3LOcOu0fdFGKCigKpeB2zkIJRMQOI7tp8RAQiOfICAM1zyf92mU9QWRqmRQL3ptYHsk58 9y1/LY4kKTSrvSK6vgkOWO1Z0uA9D/+BcpILGuxP4IB5yjMqhw1sbrRkk0srk60OtdegiSblf 5YZ9bu8YLOirygwd9Vqnr0LNwoqEt7GBVDdxxL2dj/ogUO173SYVzPubsiNZ1zwcRwDWRIFx/ uJ2vMnRkv99SIYO52tzRUjjLWsVWL8Dj5irPzcwJwm27+isrGiMTUG5mC4uoKSI+mn+I3q4jn bkxOvPoEU2ERdcLQz0FhnEXlF1+urX/JE/8AQx6flDxDRB0gOED55PSl0T7e2MaYQu2k= Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org We get a bogus warning about a potential uninitialized variable use in gfs2, because the compiler does not figure out that we never use the leaf number if get_leaf_nr() returns an error: fs/gfs2/dir.c: In function 'get_first_leaf': fs/gfs2/dir.c:802:9: warning: 'leaf_no' may be used uninitialized in this function [-Wmaybe-uninitialized] fs/gfs2/dir.c: In function 'dir_split_leaf': fs/gfs2/dir.c:1021:8: warning: 'leaf_no' may be used uninitialized in this function [-Wmaybe-uninitialized] Changing the 'if (!error)' to 'if (!IS_ERR_VALUE(error))' is sufficient to let gcc understand that this is exactly the same condition as in IS_ERR() so it can optimize the code path enough to understand it. Signed-off-by: Arnd Bergmann --- fs/gfs2/dir.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) -- 2.7.0 diff --git a/fs/gfs2/dir.c b/fs/gfs2/dir.c index 6a92592304fb..d4014af4f064 100644 --- a/fs/gfs2/dir.c +++ b/fs/gfs2/dir.c @@ -798,7 +798,7 @@ static int get_first_leaf(struct gfs2_inode *dip, u32 index, int error; error = get_leaf_nr(dip, index, &leaf_no); - if (!error) + if (!IS_ERR_VALUE(error)) error = get_leaf(dip, leaf_no, bh_out); return error; @@ -1014,7 +1014,7 @@ static int dir_split_leaf(struct inode *inode, const struct qstr *name) index = name->hash >> (32 - dip->i_depth); error = get_leaf_nr(dip, index, &leaf_no); - if (error) + if (IS_ERR_VALUE(error)) return error; /* Get the old leaf block */