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=-14.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT 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 5A77AC433DF for ; Mon, 15 Jun 2020 08:50:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 334D620679 for ; Mon, 15 Jun 2020 08:50:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729145AbgFOIu2 (ORCPT ); Mon, 15 Jun 2020 04:50:28 -0400 Received: from szxga06-in.huawei.com ([45.249.212.32]:59672 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728496AbgFOIu1 (ORCPT ); Mon, 15 Jun 2020 04:50:27 -0400 Received: from DGGEMS414-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id 354B83BC7BB72B2C8655; Mon, 15 Jun 2020 16:50:23 +0800 (CST) Received: from huawei.com (10.175.127.227) by DGGEMS414-HUB.china.huawei.com (10.3.19.214) with Microsoft SMTP Server id 14.3.487.0; Mon, 15 Jun 2020 16:50:13 +0800 From: Jason Yan To: , , , CC: , Jason Yan , Kees Cook , Chao Yu Subject: [PATCH] f2fs: Eliminate usage of uninitialized_var() macro Date: Mon, 15 Jun 2020 16:51:32 +0800 Message-ID: <20200615085132.166470-1-yanaijie@huawei.com> X-Mailer: git-send-email 2.25.4 MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII X-Originating-IP: [10.175.127.227] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is an effort to eliminate the uninitialized_var() macro[1]. The use of this macro is the wrong solution because it forces off ANY analysis by the compiler for a given variable. It even masks "unused variable" warnings. Quoted from Linus[2]: "It's a horrible thing to use, in that it adds extra cruft to the source code, and then shuts up a compiler warning (even the _reliable_ warnings from gcc)." Fix it by remove this variable since it is not needed at all. [1] https://github.com/KSPP/linux/issues/81 [2] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/ Cc: Kees Cook Suggested-by: Chao Yu Signed-off-by: Jason Yan --- v2: Directly remove this variable. fs/f2fs/data.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index 326c63879ddc..3753ba06531b 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -2856,7 +2856,6 @@ static int f2fs_write_cache_pages(struct address_space *mapping, }; #endif int nr_pages; - pgoff_t uninitialized_var(writeback_index); pgoff_t index; pgoff_t end; /* Inclusive */ pgoff_t done_index; @@ -2875,8 +2874,7 @@ static int f2fs_write_cache_pages(struct address_space *mapping, clear_inode_flag(mapping->host, FI_HOT_DATA); if (wbc->range_cyclic) { - writeback_index = mapping->writeback_index; /* prev offset */ - index = writeback_index; + index = mapping->writeback_index; /* prev offset */ end = -1; } else { index = wbc->range_start >> PAGE_SHIFT; -- 2.25.4