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=-7.0 required=3.0 tests=INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,URIBL_BLOCKED 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 B55EAC43381 for ; Thu, 14 Mar 2019 10:11:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 843E820854 for ; Thu, 14 Mar 2019 10:11:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726922AbfCNKLJ convert rfc822-to-8bit (ORCPT ); Thu, 14 Mar 2019 06:11:09 -0400 Received: from einhorn-mail.in-berlin.de ([217.197.80.20]:43273 "EHLO einhorn-mail.in-berlin.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726643AbfCNKLJ (ORCPT ); Thu, 14 Mar 2019 06:11:09 -0400 X-Greylist: delayed 603 seconds by postgrey-1.27 at vger.kernel.org; Thu, 14 Mar 2019 06:11:07 EDT X-Envelope-From: stefanr@s5r6.in-berlin.de Received: from authenticated.user (localhost [127.0.0.1]) by einhorn.in-berlin.de with ESMTPSA id x2EA0dv9009635 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 14 Mar 2019 11:00:39 +0100 Date: Thu, 14 Mar 2019 11:00:38 +0100 From: Stefan Richter To: "Gustavo A. R. Silva" Cc: linux1394-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, Kees Cook , Mathieu Malaterre Subject: Re: [PATCH] firewire: mark expected switch fall-throughs Message-ID: <20190314110038.7ef825de@kant> In-Reply-To: <20190211180356.GA27613@embeddedor> References: <20190211180356.GA27613@embeddedor> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 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 (added Cc: Mathieu Malaterre, who sent a patch which is a subset of this) On Feb 11 Gustavo A. R. Silva wrote: > In preparation to enabling -Wimplicit-fallthrough, mark switch > cases where we are expecting to fall through. > > This patch fixes the following warnings: > > drivers/firewire/core-device.c: In function ‘set_broadcast_channel’: > drivers/firewire/core-device.c:969:7: warning: this statement may fall through [-Wimplicit-fallthrough=] > if (data & cpu_to_be32(1 << 31)) { > ^ > drivers/firewire/core-device.c:974:3: note: here > case RCODE_ADDRESS_ERROR: > ^~~~ > drivers/firewire/core-iso.c: In function ‘manage_channel’: > drivers/firewire/core-iso.c:308:7: warning: this statement may fall through [-Wimplicit-fallthrough=] > if ((data[0] & bit) == (data[1] & bit)) > ^ > drivers/firewire/core-iso.c:312:3: note: here > default: > ^~~~~~~ > drivers/firewire/core-topology.c: In function ‘count_ports’: > drivers/firewire/core-topology.c:69:23: warning: this statement may fall through [-Wimplicit-fallthrough=] > (*child_port_count)++; > ~~~~~~~~~~~~~~~~~~~^~ > drivers/firewire/core-topology.c:70:3: note: here > case SELFID_PORT_PARENT: > ^~~~ > > Warning level 3 was used: -Wimplicit-fallthrough=3 > > Notice that in some cases, the code comment is modified in > accordance with what GCC is expecting to find. OK, I looked up https://gcc.gnu.org/onlinedocs/gcc-8.3.0/gcc/Warning-Options.html#index-Wimplicit-fallthrough now. I am loudly sighing and rolling my eyes... Anyway; the last regex listed at the Wimplicit-fallthrough=3 bullet point is obviously the one you are wanting to match. > This patch is part of the ongoing efforts to enable > -Wimplicit-fallthrough. > > Signed-off-by: Gustavo A. R. Silva > --- > drivers/firewire/core-device.c | 2 +- > drivers/firewire/core-iso.c | 2 +- > drivers/firewire/core-topology.c | 1 + > 3 files changed, 3 insertions(+), 2 deletions(-) > > diff --git a/drivers/firewire/core-device.c b/drivers/firewire/core-device.c > index 7c2eed76011e..0c86548fa4a7 100644 > --- a/drivers/firewire/core-device.c > +++ b/drivers/firewire/core-device.c > @@ -970,7 +970,7 @@ static void set_broadcast_channel(struct fw_device *device, int generation) > device->bc_implemented = BC_IMPLEMENTED; > break; > } > - /* else fall through to case address error */ > + /* else, fall through - to case address error */ > case RCODE_ADDRESS_ERROR: > device->bc_implemented = BC_UNIMPLEMENTED; > } > diff --git a/drivers/firewire/core-iso.c b/drivers/firewire/core-iso.c > index 35e784cffc23..7e5c98840b80 100644 > --- a/drivers/firewire/core-iso.c > +++ b/drivers/firewire/core-iso.c > @@ -308,7 +308,7 @@ static int manage_channel(struct fw_card *card, int irm_id, int generation, > if ((data[0] & bit) == (data[1] & bit)) > continue; > > - /* 1394-1995 IRM, fall through to retry. */ > + /* fall through - to retry for 1394-1995 IRM */ If you don't mind, I will apply your patch with a different wording of this comment: /* fall through - It's an 1394-1995 IRM, retry. */ I'll mark my modification to your patch in the signed-off-by-tag. > default: > if (retry) { > retry--; > diff --git a/drivers/firewire/core-topology.c b/drivers/firewire/core-topology.c > index 7db234d3fbdd..82c67e900aad 100644 > --- a/drivers/firewire/core-topology.c > +++ b/drivers/firewire/core-topology.c > @@ -67,6 +67,7 @@ static u32 *count_ports(u32 *sid, int *total_port_count, int *child_port_count) > switch (port_type) { > case SELFID_PORT_CHILD: > (*child_port_count)++; > + /* fall through */ > case SELFID_PORT_PARENT: > case SELFID_PORT_NCONN: > (*total_port_count)++; -- Stefan Richter -======---== --== -===- http://arcgraph.de/sr/