From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: bignum branch Date: Wed, 18 Jul 2018 05:41:05 +0300 Message-ID: <838t696zb2.fsf@gnu.org> References: <87o9fbbw1t.fsf@tromey.com> <86in5jdj49.fsf@gmail.com> <83wotxaiwi.fsf@gnu.org> <86k1pxmvmx.fsf@gmail.com> <83efg4a6ie.fsf@gnu.org> <41221ccf-0c1a-c7e6-2204-e3f9056f7eb5@cs.ucla.edu> <838t6c9wx5.fsf@gnu.org> <53ba128d-7888-e15a-c4a2-1d7a65f51345@cs.ucla.edu> <83wotu7fcj.fsf@gnu.org> <83k1pt7q1e.fsf@gnu.org> <83h8kx7oeu.fsf@gnu.org> <83fu0h7nr6.fsf@gnu.org> <83d0vl7kg2.fsf@gnu.org> <4bc2a6ba-bc73-c4a9-f7a6-20303955bc7f@cs.ucla.edu> NNTP-Posting-Host: blaine.gmane.org X-Trace: blaine.gmane.org 1531881571 15037 195.159.176.226 (18 Jul 2018 02:39:31 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Wed, 18 Jul 2018 02:39:31 +0000 (UTC) Cc: andrewjmoreton@gmail.com, emacs-devel@gnu.org To: Paul Eggert Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Wed Jul 18 04:39:27 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 1ffcNA-0003p9-Ty for ged-emacs-devel@m.gmane.org; Wed, 18 Jul 2018 04:39:25 +0200 Original-Received: from localhost ([::1]:34374 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ffcPH-0004U9-N3 for ged-emacs-devel@m.gmane.org; Tue, 17 Jul 2018 22:41:35 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:60068) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ffcOe-0004U3-FG for emacs-devel@gnu.org; Tue, 17 Jul 2018 22:40:57 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ffcOb-0002ZB-A0 for emacs-devel@gnu.org; Tue, 17 Jul 2018 22:40:56 -0400 Original-Received: from fencepost.gnu.org ([2001:4830:134:3::e]:51267) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ffcOb-0002Z0-4s; Tue, 17 Jul 2018 22:40:53 -0400 Original-Received: from [176.228.60.248] (port=2117 helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:RSA_AES_256_CBC_SHA1:256) (Exim 4.82) (envelope-from ) id 1ffcOa-0006W4-He; Tue, 17 Jul 2018 22:40:52 -0400 In-reply-to: <4bc2a6ba-bc73-c4a9-f7a6-20303955bc7f@cs.ucla.edu> (message from Paul Eggert on Tue, 17 Jul 2018 15:39:02 -0700) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 2001:4830:134:3::e 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:227528 Archived-At: > Cc: andrewjmoreton@gmail.com, emacs-devel@gnu.org > From: Paul Eggert > Date: Tue, 17 Jul 2018 15:39:02 -0700 > > There's another thing about debugging. This stuff is still uncertain. That is, > there are no doubt bugs in the bignum branch in this area, and we don't know yet > how significant these correctness problems will be. With that in mind, it would > be useful to have avoid-libgmp options with our own GMP replacement that uses > uintmax_t limbs (or 'unsigned int' limbs, for that matter) for debugging > purposes, to help us debug the inevitable glitches that will arise due to > libgmp's limbs being wrong for some types. > > I looked into libgmp, and it appears that all we would need is a 2-line change > to mini-gmp.h. This should not be hard to maintain ourselves, with the idea of > propagating it upstream when we can. Could you please elaborate and perhaps show an example or two? I don't think I understand what change you are proposing to make, and how will that help debugging. Thanks.