From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762425AbWLKEtO (ORCPT ); Sun, 10 Dec 2006 23:49:14 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1762430AbWLKEtN (ORCPT ); Sun, 10 Dec 2006 23:49:13 -0500 Received: from liaag2aa.mx.compuserve.com ([149.174.40.154]:36553 "EHLO liaag2aa.mx.compuserve.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1762445AbWLKEtK (ORCPT ); Sun, 10 Dec 2006 23:49:10 -0500 Date: Sun, 10 Dec 2006 23:46:45 -0500 From: Chuck Ebbert <76306.1226@compuserve.com> Subject: Re: Linux portability bugs To: mariusn Cc: linux-kernel@vger.kernel.org Message-ID: <200612102347_MC3-1-D49B-AB99@compuserve.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org In-Reply-To: On Fri, 1 Dec 2006 22:39:01 -0800, mariusn wrote: > I am a graduate student at University of Washington, building a tool > automatically discover portability bugs in system-level code written > in C. My definition of "portability" is at the data layout level, > accounting for differences in alignment, padding, and generally layout > policies on various platforms. E.g., one might perform a pointer cast > that only works as intended when doubles are 4-byte aligned, which is > the case with gcc/ia-32 (default options) but not with gcc/sparc (due > to sparc's limited support for accessing doubles on non-8-byte > boundaries). > > I am looking for advice on how/where to look for these kinds of bugs > in the kernel and related software. This (dated) document > (http://netwinder.osuosl.org/users/b/brianbr/public_html/alignment.html > ) describes exactly these sorts of issues in the context of Linux/ARM > and mentions things like the kernel, binutils, cpio, X11, Orbit, as > sources of these sorts of bugs. I am having a bit of a hard time > locating change logs and otherwise related information on where these > bugs occurred, patches that addressed them, etc. Look for "compat" in the patch title and comments, like this one: http://www.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=46c5ea3c9ae7fbc6e52a13c92e59d4fc7f4ca80a -- Chuck "Even supernovas have their duller moments."