Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753057AbdFSTBC (ORCPT + 2 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 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 List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: 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(-) 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 */ -- 2.8.0.rc2.1.gbe9624a