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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 C7F7DC433E1 for ; Tue, 18 Aug 2020 08:56:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A470B2078B for ; Tue, 18 Aug 2020 08:56:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726145AbgHRI42 convert rfc822-to-8bit (ORCPT ); Tue, 18 Aug 2020 04:56:28 -0400 Received: from eu-smtp-delivery-151.mimecast.com ([207.82.80.151]:36034 "EHLO eu-smtp-delivery-151.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726581AbgHRI41 (ORCPT ); Tue, 18 Aug 2020 04:56:27 -0400 Received: from AcuMS.aculab.com (156.67.243.126 [156.67.243.126]) (Using TLS) by relay.mimecast.com with ESMTP id uk-mta-54-fr6a1Gp7PCek2qBtx_YSwg-1; Tue, 18 Aug 2020 09:56:22 +0100 X-MC-Unique: fr6a1Gp7PCek2qBtx_YSwg-1 Received: from AcuMS.Aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) by AcuMS.aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Tue, 18 Aug 2020 09:56:22 +0100 Received: from AcuMS.Aculab.com ([fe80::43c:695e:880f:8750]) by AcuMS.aculab.com ([fe80::43c:695e:880f:8750%12]) with mapi id 15.00.1347.000; Tue, 18 Aug 2020 09:56:22 +0100 From: David Laight To: 'Ingo Molnar' , Linus Torvalds CC: Pavel Machek , "Eric W. Biederman" , Al Viro , Michael Witten , Masahiro Yamada , Michal Marek , Cong Wang , "Johannes Weiner" , Sam Ravnborg , "Linux Kernel Mailing List" , Linux Kbuild mailing list , John Levon , "John Levon" , Andrew Morton Subject: RE: [PATCH] Makefile: Yes. Finally remove '-Wdeclaration-after-statement' Thread-Topic: [PATCH] Makefile: Yes. Finally remove '-Wdeclaration-after-statement' Thread-Index: AQHWdR7fdrR7Y2b6OUCIIALK0604z6k9jrEQ Date: Tue, 18 Aug 2020 08:56:22 +0000 Message-ID: References: <20200816175303.GB1236603@ZenIV.linux.org.uk> <20200817204223.GB12414@amd> <87lfid6kpi.fsf@x220.int.ebiederm.org> <20200817220908.GA3701@amd> <20200818051717.GA3134537@gmail.com> In-Reply-To: <20200818051717.GA3134537@gmail.com> Accept-Language: en-GB, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.107] MIME-Version: 1.0 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=C51A453 smtp.mailfrom=david.laight@aculab.com X-Mimecast-Spam-Score: 0.001 X-Mimecast-Originator: aculab.com Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kbuild-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org > I'm a big fan of -Wdeclaration-after-statement and I think C++ style > mixed variables/statements code has several disadvantages: Agreed. Personally I think declarations should either be either right at the top of a function or in a very small code block. Otherwise they are annoying to find. You also get very hard to spot bugs unless -Wshadow is enabled (I can't remember if the linux kernel has it enabled). C++ (sort of) has to allow definitions in the middle of code blocks because it doesn't allow uninitialised variables - so definitions are best delayed until the copy-constructor can be used. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)