From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andi Kleen Subject: Re: [PATCH 1/2] Remove noreturn function pointers in usage.c Date: Thu, 9 Jun 2011 06:59:15 +0200 Message-ID: <20110609045915.GA15448@one.firstfloor.org> References: <1307569417-8924-1-git-send-email-andi@firstfloor.org> <7v4o3z264s.fsf@alter.siamese.dyndns.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Andi Kleen , git@vger.kernel.org, Andi Kleen To: Junio C Hamano X-From: git-owner@vger.kernel.org Thu Jun 09 06:59:26 2011 Return-path: Envelope-to: gcvg-git-2@lo.gmane.org Received: from vger.kernel.org ([209.132.180.67]) by lo.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1QUXL3-0004sl-0d for gcvg-git-2@lo.gmane.org; Thu, 09 Jun 2011 06:59:25 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751341Ab1FIE7T (ORCPT ); Thu, 9 Jun 2011 00:59:19 -0400 Received: from one.firstfloor.org ([213.235.205.2]:45579 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750819Ab1FIE7S (ORCPT ); Thu, 9 Jun 2011 00:59:18 -0400 Received: by one.firstfloor.org (Postfix, from userid 503) id 0FE721ED80AD; Thu, 9 Jun 2011 06:59:16 +0200 (CEST) Content-Disposition: inline In-Reply-To: <7v4o3z264s.fsf@alter.siamese.dyndns.org> User-Agent: Mutt/1.4.2.2i Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: > - There are many more NORETURN and NORETURN_PTR in the code, and the > proposed commit log message does not explain why these two are the only > ones that are problematic and needs to be worked around. It does not > guide other people who might want to add NORETURN/NORETURN_PTR when > deciding if their change would break the "fix" this change brought in. This was the only place where it crashed the compiler. I don't have a good criterium to decide which cases do crash the compiler or not except for trying it. But I believe the crash is relatively unlikely (needs quite a lot of conditions to line up), so it doesn't deserve extensive changes all over. > > - Potential impact to people who do not use Gcc 4.6 with profile feedback > is not explained away well, except for "Doesn't seem to make any > difference." I merely went by "there are no new warnings" (I assume that's the main motivation) > > - If other NORETURN/NORETURN_PTR could/should also go (I don't know due > to the first bullet point above) when using the problematic compiler > with the profile feedback feature, wouldn't it be a better workaround > would be to introduce a Makefile variable to ask git-compat-util.h to > make these two a no-op, perhaps? I don't think we need to remove the others for now. > > A patch to do so may look like this. > > I did not like the triple negation "make NO_NORETURN=NoThanks" and wanted > to name this AVOID_NORETURN instead, but decided to go with other existing > Makefile variables. Given the explanation above (I can update the description with that) do you still want the complete disabling? -Andi