Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1164237AbWLHAgh (ORCPT ); Thu, 7 Dec 2006 19:36:37 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1164235AbWLHAgh (ORCPT ); Thu, 7 Dec 2006 19:36:37 -0500 Received: from mx2.cs.washington.edu ([128.208.2.105]:47834 "EHLO mx2.cs.washington.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1164234AbWLHAgg (ORCPT ); Thu, 7 Dec 2006 19:36:36 -0500 Date: Thu, 7 Dec 2006 16:36:31 -0800 (PST) From: David Rientjes To: Mariusz Kozlowski cc: Amit Choudhary , Linux Kernel Subject: Re: [PATCH 2.6.19] drivers/media/video/cpia2/cpia2_usb.c: Free previously allocated memory (in array elements) if kmalloc() returns NULL. In-Reply-To: <200612080109.27018.m.kozlowski@tuxland.pl> Message-ID: References: <20061206211317.b996bc34.amit2030@gmail.com> <200612080050.53895.m.kozlowski@tuxland.pl> <200612080109.27018.m.kozlowski@tuxland.pl> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1307 Lines: 48 On Fri, 8 Dec 2006, Mariusz Kozlowski wrote: > > > Just for future. Shorter and more readable version of your for(...) thing: > > > > > > while (i--) { > > > ... > > > } > > > > > > > No, that is not equivalent. > > > > You want > > while (i-- >= 0) { > > ... > > } > > > > Not really. That will stop at -1 not 0. > It depends on your intent. Generally speaking, while (i--) { ... } is never what you want. Adding the check for being greater than 0 stops potential bugs from signed int i being negative. The only drawback on x86 is that it sets a byte based on the greater condition with setg and tests it later with testb for every iteration. This use of testb will _always_ use the same addressable byte registers for both its operands. Based on this particular patch, I agree that while (i-- > 0) { ... } will do the job. This is equivalent to the original for loop and ensures that a negative value of i is never iterated on (even though it admittedly would never be negative in this instance to begin with). David - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/