From patchwork Mon Jun 19 18:32:31 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Willy Tarreau X-Patchwork-Id: 105920 Delivered-To: patch@linaro.org Received: by 10.140.91.2 with SMTP id y2csp1018421qgd; Mon, 19 Jun 2017 12:01:14 -0700 (PDT) X-Received: by 10.84.175.3 with SMTP id s3mr30896425plb.105.1497898874282; Mon, 19 Jun 2017 12:01:14 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1497898874; cv=none; d=google.com; s=arc-20160816; b=QLm96yU7z89DUba9ZnsUlw/Mm3dRId0qFezlqTS0jzUsORrAw89244nMw2JHEPrz/h nG42uLvTcm44XZoH2aBTH71v8xpDaPo5XGHFVWJ197OPXudKM/6ACRb/xixa5J46Xf06 Y3rjT1kabZixUyGJwj5rKZVOWv2oa/WZqyudNBXIdBSKeBQllDWCrEuwyesloDMWLIXK 6OFYD3TQJKCFnvCGng1SFkkf7nSBi+riWe3jk7uXQRVBB6IUMM3+RdU04zk527x3M/Vr JGS5GfRxzA2GyqAJtvKjlKOWJDMq3f3kG24ZKNETZDcl51/2C9Bam6mBLPHqKLUE11l8 mYbg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:references:in-reply-to:message-id:date :subject:cc:to:from:arc-authentication-results; bh=/SVrq8ITXShDDoSbJivFJA6i6XaXwhU/cRbrsPzZC0w=; b=CHOQPJP4iVPHROXiMDOGPTRGfVLXcMzNnD1tpEEnuzgJaE9VjV4LvAQU5G8gzhBkUJ W6Fxv0tYecLhqyX5Y4JCN12yKaQlb7klgLavv+vYlnvm/Z8g9o7vKcCBq5+UuHCHWNXg YeynQhzVOGXOrC/U/2xPOvehWKL04Up2LnSwUMBZppOSyaqavJ4AjUG2Gz+lJtKLYZ7Q 7MG04Og6a/D2DMeDcp1hooIPmQUD40UfVQ8faoER2B/C2iCN3sXcEzDymAAdclzBbAtD rKKmfZDSCvSOT4WmRlCliM4H0gTK2w1DhlMsAE+PeZrbXNmcF/4IAbBk3oYGXkeZ+HGl hNSQ== ARC-Authentication-Results: i=1; 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 Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id 7si8597708pfh.150.2017.06.19.12.01.14; Mon, 19 Jun 2017 12:01:14 -0700 (PDT) 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 S1753057AbdFSTBC (ORCPT + 25 others); Mon, 19 Jun 2017 15:01:02 -0400 Received: from wtarreau.pck.nerim.net ([62.212.114.60]:52555 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753747AbdFSShp (ORCPT ); Mon, 19 Jun 2017 14:37:45 -0400 Received: (from willy@localhost) by pcw.home.local (8.15.2/8.15.2/Submit) id v5JIY1Er015118; Mon, 19 Jun 2017 20:34:01 +0200 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, linux@roeck-us.net Cc: Arnd Bergmann , Bob Peterson , Willy Tarreau Subject: [PATCH 3.10 252/268] gfs2: avoid uninitialized variable warning Date: Mon, 19 Jun 2017 20:32:31 +0200 Message-Id: <1497897167-14556-253-git-send-email-w@1wt.eu> X-Mailer: git-send-email 2.8.0.rc2.1.gbe9624a In-Reply-To: <1497897167-14556-1-git-send-email-w@1wt.eu> References: <1497897167-14556-1-git-send-email-w@1wt.eu> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Arnd Bergmann commit 67893f12e5374bbcaaffbc6e570acbc2714ea884 upstream. 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 Signed-off-by: Bob Peterson Signed-off-by: Willy Tarreau --- fs/gfs2/dir.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) -- 2.8.0.rc2.1.gbe9624a diff --git a/fs/gfs2/dir.c b/fs/gfs2/dir.c index b631c90..9aaa6db 100644 --- a/fs/gfs2/dir.c +++ b/fs/gfs2/dir.c @@ -763,7 +763,7 @@ 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; @@ -974,7 +974,7 @@ 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 */