From patchwork Sat Apr 18 18:41:02 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Randy Dunlap X-Patchwork-Id: 11496855 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id F03BF81 for ; Sat, 18 Apr 2020 18:41:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D85832223F for ; Sat, 18 Apr 2020 18:41:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="XCwSjlVe" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727946AbgDRSlV (ORCPT ); Sat, 18 Apr 2020 14:41:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41194 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1726320AbgDRSlR (ORCPT ); Sat, 18 Apr 2020 14:41:17 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 90C78C061A41; Sat, 18 Apr 2020 11:41:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Content-Transfer-Encoding: Content-Type:MIME-Version:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To: Content-ID:Content-Description:In-Reply-To:References; bh=d5zfrylOKoUmkiJ/VV8Fl3fzLkxXbmDEJr/3MIsevyo=; b=XCwSjlVez+qHxOPmcyTIK6oiMp olawr70vtpi0V1QI9XKQUEdNlzc7gZtydJwYjHnNgNwCiR0Y8ytqLU1885mYKcfU2nNRcSQ+hBEej MiJH64ZiTrBz5h80SHKV7B2XhV/8NA5dx2/XMstBP2kRcY+jAyFTPEP07dibSEvWPpw6URRhjEARq GsW6VSkFXNXfFpWKtacsKtxhxuNePEr2gYhZGljGT1rr1HkTT8hxKqdKHdiJLDwOvTjuHdAESVOeL NqEnuUJjyC5UmLntvc7lJwAg8Acv/O1w1fMRoAZtCHCPa4lyuiz4kTPN/HiIYqU17pqZ6fxYiBEQ9 d15hNa1Q==; Received: from [2601:1c0:6280:3f0::19c2] (helo=smtpauth.infradead.org) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jPsOv-0007rZ-9I; Sat, 18 Apr 2020 18:41:13 +0000 From: Randy Dunlap To: linux-kernel@vger.kernel.org Cc: Randy Dunlap , Linus Torvalds , Andrew Morton , Alexander Viro , linux-fsdevel@vger.kernel.org, Dmitry Torokhov , linux-input@vger.kernel.org, Jaroslav Kysela , Takashi Iwai , alsa-devel@alsa-project.org, Greg Kroah-Hartman , linux-usb@vger.kernel.org, "J. Bruce Fields" , Chuck Lever , linux-nfs@vger.kernel.org, Johannes Berg , Dan Williams , Vishal Verma , Dave Jiang , linux-nvdimm@lists.01.org, "Martin K. Petersen" , linux-scsi@vger.kernel.org, target-devel@vger.kernel.org, Zzy Wysm Subject: [RFC PATCH 0/9] fix -Wempty-body build warnings Date: Sat, 18 Apr 2020 11:41:02 -0700 Message-Id: <20200418184111.13401-1-rdunlap@infradead.org> X-Mailer: git-send-email 2.16.4 MIME-Version: 1.0 Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org Hi, When -Wextra is used, gcc emits many warnings about an empty 'if' or 'else' body, like this: ../fs/posix_acl.c: In function ‘get_acl’: ../fs/posix_acl.c:127:22: warning: suggest braces around empty body in an ‘if’ statement [-Wempty-body] /* fall through */ ; ^ To quieten these warnings, add a new macro "do_empty()". I originally wanted to use do_nothing(), but that's already in use. It would sorta be nice if "fallthrough" could be coerced for this instead of using something like do_empty(). Or should we just use "{}" in place of ";"? This causes some odd coding style issue IMO. E.g., see this change: original: if (cmpxchg(p, ACL_NOT_CACHED, sentinel) != ACL_NOT_CACHED) /* fall through */ ; with new macro: if (cmpxchg(p, ACL_NOT_CACHED, sentinel) != ACL_NOT_CACHED) do_empty(); /* fall through */ using {}: if (cmpxchg(p, ACL_NOT_CACHED, sentinel) != ACL_NOT_CACHED) {} /* fall through */ or { /* fall through */ } or even if (cmpxchg(p, ACL_NOT_CACHED, sentinel) != ACL_NOT_CACHED) { /* fall through */ } or if (cmpxchg(p, ACL_NOT_CACHED, sentinel) != ACL_NOT_CACHED) { } /* fall through */ drivers/base/devcoredump.c | 5 +++-- drivers/dax/bus.c | 5 +++-- drivers/input/mouse/synaptics.c | 3 ++- drivers/target/target_core_pscsi.c | 3 ++- drivers/usb/core/sysfs.c | 2 +- fs/nfsd/nfs4state.c | 3 ++- fs/posix_acl.c | 2 +- include/linux/kernel.h | 8 ++++++++ sound/drivers/vx/vx_core.c | 3 ++- 9 files changed, 24 insertions(+), 10 deletions(-)