From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf1-f197.google.com (mail-pf1-f197.google.com [209.85.210.197]) by kanga.kvack.org (Postfix) with ESMTP id 027838E0047 for ; Thu, 24 Jan 2019 03:10:29 -0500 (EST) Received: by mail-pf1-f197.google.com with SMTP id b17so3978211pfc.11 for ; Thu, 24 Jan 2019 00:10:28 -0800 (PST) Received: from mail.kernel.org (mail.kernel.org. [198.145.29.99]) by mx.google.com with ESMTPS id d82si21001951pfj.124.2019.01.24.00.10.27 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 24 Jan 2019 00:10:27 -0800 (PST) Date: Thu, 24 Jan 2019 09:10:24 +0100 From: Greg KH Subject: Re: [Intel-gfx] [PATCH 1/3] treewide: Lift switch variables out of switches Message-ID: <20190124081024.GA1108@kroah.com> References: <20190123110349.35882-1-keescook@chromium.org> <20190123110349.35882-2-keescook@chromium.org> <20190123115829.GA31385@kroah.com> <874l9z31c5.fsf@intel.com> <000001d4b32a$845e06e0$8d1a14a0$@211mainstreet.net> <87va2f1int.fsf@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: Kees Cook Cc: Jani Nikula , Edwin Zimmerman , dev@openvswitch.org, Ard Biesheuvel , Network Development , intel-gfx@lists.freedesktop.org, linux-usb@vger.kernel.org, LKML , Maling list - DRI developers , Linux-MM , linux-security-module , Kernel Hardening , intel-wired-lan@lists.osuosl.org, "linux-fsdevel@vger.kernel.org" , xen-devel , Laura Abbott , linux-kbuild , Alexander Popov On Thu, Jan 24, 2019 at 07:55:51AM +1300, Kees Cook wrote: > On Thu, Jan 24, 2019 at 4:44 AM Jani Nikula wrote: > > > > On Wed, 23 Jan 2019, Edwin Zimmerman wrote: > > > On Wed, 23 Jan 2019, Jani Nikula wrote: > > >> On Wed, 23 Jan 2019, Greg KH wrote: > > >> > On Wed, Jan 23, 2019 at 03:03:47AM -0800, Kees Cook wrote: > > >> >> Variables declared in a switch statement before any case statements > > >> >> cannot be initialized, so move all instances out of the switches. > > >> >> After this, future always-initialized stack variables will work > > >> >> and not throw warnings like this: > > >> >> > > >> >> fs/fcntl.c: In function ‘send_sigio_to_task’: > > >> >> fs/fcntl.c:738:13: warning: statement will never be executed [-Wswitch-unreachable] > > >> >> siginfo_t si; > > >> >> ^~ > > >> > > > >> > That's a pain, so this means we can't have any new variables in { } > > >> > scope except for at the top of a function? > > Just in case this wasn't clear: no, it's just the switch statement > before the first "case". I cannot imagine how bad it would be if we > couldn't have block-scoped variables! Heh. :) Sorry, it was not clear at first glance. So no more objection from me for this change. greg k-h