From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161224AbWG1SgR (ORCPT ); Fri, 28 Jul 2006 14:36:17 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1161226AbWG1SgR (ORCPT ); Fri, 28 Jul 2006 14:36:17 -0400 Received: from ns2.suse.de ([195.135.220.15]:59585 "EHLO mx2.suse.de") by vger.kernel.org with ESMTP id S1161224AbWG1SgR (ORCPT ); Fri, 28 Jul 2006 14:36:17 -0400 From: Andi Kleen To: Chuck Ebbert <76306.1226@compuserve.com> Subject: Re: [patch 1/2] i386: add CFI macros for stack manipulation Date: Fri, 28 Jul 2006 20:36:45 +0200 User-Agent: KMail/1.9.1 Cc: linux-kernel , Jan Beulich , Andrew Morton , Linus Torvalds References: <200607281353_MC3-1-C662-536D@compuserve.com> In-Reply-To: <200607281353_MC3-1-C662-536D@compuserve.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200607282036.45608.ak@suse.de> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Friday 28 July 2006 19:50, Chuck Ebbert wrote: > Add macros to dwarf2.h to simplify pushing and popping stack > variables. I feared someone would do that patch. I've thought about it myself. However it's not a good idea. I've already had complaints that some code in x86-64 is too hard to read/debug because it uses too many macros. I think it's better if the core core still uses "real" instructions and keep the CFI_* stuff as annotation that most people can just ignore. With your change that wouldn't be the case and everybody hacking the code would need to know all of CFI too, which is still quite arcane stuff. So while it would make the source shorter and require less typing I don't think it's good for readability. What would be a good thing if someone could write it up would be a short tutorial for Documentation/* on CFI -Andi