From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752799AbaB0TTx (ORCPT ); Thu, 27 Feb 2014 14:19:53 -0500 Received: from moutng.kundenserver.de ([212.227.17.24]:58688 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751202AbaB0TTv (ORCPT ); Thu, 27 Feb 2014 14:19:51 -0500 From: Arnd Bergmann To: Josh Triplett Subject: Re: [PATCH v2 5/5] bug: Make BUG() call unreachable() Date: Thu, 27 Feb 2014 20:19:47 +0100 User-Agent: KMail/1.12.2 (Linux/3.8.0-22-generic; KDE/4.3.2; x86_64; ; ) Cc: Andrew Morton , linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org References: <469b5dc113cb468232291527642f8dc47663e945.1393385236.git.josh@joshtriplett.org> <201402261429.06553.arnd@arndb.de> <20140226145806.GA24150@thin> In-Reply-To: <20140226145806.GA24150@thin> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201402272019.47554.arnd@arndb.de> X-Provags-ID: V02:K0:u1slykXed1/4uBF1DKdqBL3rwn27arSFkO49eW4SZI0 TcF2QYxOhlPeR1utJDVYAeE3Ky6fnVw+4XPOA4uIomws2ZZ6rS BFrH6WKS0OwPuVFJuw+vsh13nd+lM2b7zkkNDXZTu1jcsZoMjc 3czGJzzMCJ4uKeHN14MyEScgVmFhHLcGRgCCtOBYZm01n2tD/L +uI7Ksx6QdCgv/X+NvOC9W+sv2fIHay1DSDAeXMVmzI9HMjIU2 7JHTKaOOZF5GfO2Z5qCEgORERjxhzdwFhQLhZWa0x7Us8BJ5+S e2esXb+i7bb6jmQtrGZbdmYtdMRCNTDrwS+2mBRBjyTnxjAn3j 6nlpcQUsCFCb/6Ej5vMY= Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wednesday 26 February 2014, Josh Triplett wrote: > This doesn't seem any different than compiling out assert() at runtime > in a userspace program, given how the kernel uses BUG() and BUG_ON(). > I'd argue that adding unreachable() doesn't seem like it makes the > current implementation of BUG() any worse; either way if you reach it > you have a problem. I think it's better to get a warning about undefined behavior than to suppress that warning. Arnd