From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Paul Eggert Newsgroups: gmane.emacs.devel Subject: Re: Preview: portable dumper Date: Fri, 16 Feb 2018 14:31:07 -0800 Organization: UCLA Computer Science Department Message-ID: <81f67da0-6187-d507-2628-ae638867eddc@cs.ucla.edu> References: <243e083f-6b2d-4d40-884f-87b72ddad0f6@email.android.com> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-Trace: blaine.gmane.org 1518820182 21933 195.159.176.226 (16 Feb 2018 22:29:42 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Fri, 16 Feb 2018 22:29:42 +0000 (UTC) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 Cc: Eli Zaretskii , Andy Moreton , emacs-devel@gnu.org To: Daniel Colascione Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Fri Feb 16 23:29:38 2018 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1emoVK-00044c-HR for ged-emacs-devel@m.gmane.org; Fri, 16 Feb 2018 23:29:18 +0100 Original-Received: from localhost ([::1]:39730 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1emoXK-00053n-SD for ged-emacs-devel@m.gmane.org; Fri, 16 Feb 2018 17:31:22 -0500 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:47735) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1emoXD-00053D-0s for emacs-devel@gnu.org; Fri, 16 Feb 2018 17:31:15 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1emoXC-0002Nb-8Z for emacs-devel@gnu.org; Fri, 16 Feb 2018 17:31:15 -0500 Original-Received: from zimbra.cs.ucla.edu ([131.179.128.68]:34646) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1emoX8-0002EM-Gl; Fri, 16 Feb 2018 17:31:10 -0500 Original-Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id 7749A1615AF; Fri, 16 Feb 2018 14:31:08 -0800 (PST) Original-Received: from zimbra.cs.ucla.edu ([127.0.0.1]) by localhost (zimbra.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id 7fwbaPi39SlY; Fri, 16 Feb 2018 14:31:07 -0800 (PST) Original-Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id B9F601615E5; Fri, 16 Feb 2018 14:31:07 -0800 (PST) X-Virus-Scanned: amavisd-new at zimbra.cs.ucla.edu Original-Received: from zimbra.cs.ucla.edu ([127.0.0.1]) by localhost (zimbra.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id 03BxsA_GfbH1; Fri, 16 Feb 2018 14:31:07 -0800 (PST) Original-Received: from Penguin.CS.UCLA.EDU (Penguin.CS.UCLA.EDU [131.179.64.200]) by zimbra.cs.ucla.edu (Postfix) with ESMTPSA id 9E1941615AF; Fri, 16 Feb 2018 14:31:07 -0800 (PST) In-Reply-To: <243e083f-6b2d-4d40-884f-87b72ddad0f6@email.android.com> Content-Language: en-US X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [fuzzy] X-Received-From: 131.179.128.68 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.org gmane.emacs.devel:222851 Archived-At: On 02/16/2018 02:02 PM, Daniel Colascione wrote: > I'm not sure what you mean by high quality in this context. I mean code that is written with reasonable care to check for ranges, much as Emacs normally does. For example, INTEGER_TO_CONS checks for ranges before converting its argument to EMACS_INT. When such code runs afoul of -Wconversion, my experience is that the false alarm rate is so high that -Wconversion causes more trouble than it's worth. I suspect that pdumper.c also had a bunch of false alarms, which is why it contains all that gorp with ALLOW_IMPLICIT_CONVERSION and DISALLOW_IMPLICIT_CONVERSION. I'll try to pry free some time to look in more detail at pdumper.c and see whether there's a way to fix it without worrying so much about -Wconversion. > if programmers were angels, no warnings would be necessary. The > point is to *keep* the code high quality, > Which is why I advocate not using -Wconversion: as a rule, -Wconversion takes good code and makes it worse. Of course there are always exceptions, and perhaps pdumper.c is one of those exceptions.