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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 EA0BAC31E5B for ; Mon, 17 Jun 2019 16:41:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C2E5F2070B for ; Mon, 17 Jun 2019 16:41:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727782AbfFQQlW convert rfc822-to-8bit (ORCPT ); Mon, 17 Jun 2019 12:41:22 -0400 Received: from eu-smtp-delivery-151.mimecast.com ([146.101.78.151]:32818 "EHLO eu-smtp-delivery-151.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725995AbfFQQlW (ORCPT ); Mon, 17 Jun 2019 12:41:22 -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-13-78eJaLHeN_eregkFsgmmww-1; Mon, 17 Jun 2019 17:41:19 +0100 Received: from AcuMS.Aculab.com (fd9f:af1c:a25b::d117) by AcuMS.aculab.com (fd9f:af1c:a25b::d117) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Mon, 17 Jun 2019 17:41:19 +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; Mon, 17 Jun 2019 17:41:18 +0100 From: David Laight To: 'Joe Perches' , Pavel Machek , "Shawn Landden" CC: "linux-kernel@vger.kernel.org" , "Gustavo A . R . Silva" , Andy Whitcroft Subject: RE: [PATCH] Use fall-through attribute rather than magic comments Thread-Topic: [PATCH] Use fall-through attribute rather than magic comments Thread-Index: AQHVJSlclFJUjoUp/0eCUTtyq6dWeaagCssA Date: Mon, 17 Jun 2019 16:41:18 +0000 Message-ID: <128384ca2876462b90b9f28db85194fc@AcuMS.aculab.com> References: <20190316033841.7659-1-shawn@git.icu> <20190617155643.GA32544@amd> <45e070039e66b1cb1490a78d4805bc73cc09f571.camel@perches.com> In-Reply-To: <45e070039e66b1cb1490a78d4805bc73cc09f571.camel@perches.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 X-MC-Unique: 78eJaLHeN_eregkFsgmmww-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Joe Perches > Sent: 17 June 2019 17:26 > On Mon, 2019-06-17 at 17:56 +0200, Pavel Machek wrote: > > Hi! > > > > > +/* > > > + * gcc: https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html#index-Wimplicit-fallthrough > > > + * gcc: https://developers.redhat.com/blog/2017/03/10/wimplicit-fallthrough-in-gcc-7/ > > > + */ > > > +#if __has_attribute(__fallthrough__) > > > +# define __fallthrough __attribute__((__fallthrough__)) > > > +#else > > > +# define __fallthrough > > > +#endif Should the trailing ; be added to the above? I think the above would require: case foo: bar(); __fallthrough; case baz: When commented out that leaves a completely empty statement (adjacent ;) I'm sure some compilers complain about those as well. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)