From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Mattias =?UTF-8?Q?Engdeg=C3=A5rd?= Newsgroups: gmane.emacs.bugs Subject: bug#56641: Deprecate `lsh` Date: Thu, 21 Jul 2022 09:47:52 +0200 Message-ID: <759888C8-0176-4293-BA47-984EB3E7061B@acm.org> References: <83zgh5mcqk.fsf@gnu.org> <52FF0BFF-F19C-4ABA-82BE-8FE3277B726D@acm.org> <83lespm50p.fsf@gnu.org> <87cze0bmn6.fsf@yahoo.com> <83bktkmrwx.fsf@gnu.org> <877d48bhch.fsf@yahoo.com> <752C35EB-B86F-4D5B-863D-D9AFDFE20A66@acm.org> <87k0889dp4.fsf@yahoo.com> <87y1wn8ckv.fsf@yahoo.com> Mime-Version: 1.0 (Mac OS X Mail 14.0 \(3654.120.0.1.13\)) Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="1215"; mail-complaints-to="usenet@ciao.gmane.io" Cc: Eli Zaretskii , stefankangas@gmail.com, 56641@debbugs.gnu.org To: Po Lu Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Thu Jul 21 09:48:13 2022 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1oEQur-00005f-1J for geb-bug-gnu-emacs@m.gmane-mx.org; Thu, 21 Jul 2022 09:48:13 +0200 Original-Received: from localhost ([::1]:53366 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1oEQup-0006YN-Tk for geb-bug-gnu-emacs@m.gmane-mx.org; Thu, 21 Jul 2022 03:48:11 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:36124) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oEQug-0006Xx-VG for bug-gnu-emacs@gnu.org; Thu, 21 Jul 2022 03:48:03 -0400 Original-Received: from debbugs.gnu.org ([209.51.188.43]:46848) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1oEQug-00087w-Lh for bug-gnu-emacs@gnu.org; Thu, 21 Jul 2022 03:48:02 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1oEQug-0007O4-G0 for bug-gnu-emacs@gnu.org; Thu, 21 Jul 2022 03:48:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Mattias =?UTF-8?Q?Engdeg=C3=A5rd?= Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Thu, 21 Jul 2022 07:48:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 56641 X-GNU-PR-Package: emacs Original-Received: via spool by 56641-submit@debbugs.gnu.org id=B56641.165838968128383 (code B ref 56641); Thu, 21 Jul 2022 07:48:02 +0000 Original-Received: (at 56641) by debbugs.gnu.org; 21 Jul 2022 07:48:01 +0000 Original-Received: from localhost ([127.0.0.1]:36597 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1oEQue-0007Ni-OJ for submit@debbugs.gnu.org; Thu, 21 Jul 2022 03:48:01 -0400 Original-Received: from mail18c50.megamailservers.eu ([91.136.10.28]:53422) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1oEQuc-0007NE-2G for 56641@debbugs.gnu.org; Thu, 21 Jul 2022 03:47:59 -0400 X-Authenticated-User: mattiase@bredband.net DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=megamailservers.eu; s=maildub; t=1658389676; bh=aQ1CeNKUffeNLDCAyF090Z0cKWlq/jiGZM4k0VTZN3c=; h=Subject:From:In-Reply-To:Date:Cc:References:To:From; b=iTVW1mVNmlRJgsQkQLq/3L926c6phvTx9XHaApvbWh2uUtmM/03yt7Xd/btN24MIO 3VOVB6lPxehMkk/8oi+BYu7mbQh6tiGCTWapD6uj1FfK9jBlAo4BUFtubRoNv/ht/e fSnbfPci16GaPFDbWr9AEkMqW+cwm/a+LMXNSMis= Feedback-ID: mattiase@acm.or Original-Received: from smtpclient.apple (c188-150.188-179.bredband.tele2.se [188.150.188.179] (may be forged)) (authenticated bits=0) by mail18c50.megamailservers.eu (8.14.9/8.13.1) with ESMTP id 26L7lr1g076102; Thu, 21 Jul 2022 07:47:55 +0000 In-Reply-To: <87y1wn8ckv.fsf@yahoo.com> X-Mailer: Apple Mail (2.3654.120.0.1.13) X-CTCH-RefID: str=0001.0A782F22.62D904AC.0012, ss=1, re=0.000, recu=0.000, reip=0.000, cl=1, cld=1, fgs=0 X-CTCH-VOD: Unknown X-CTCH-Spam: Unknown X-CTCH-Score: 0.000 X-CTCH-Flags: 0 X-CTCH-ScoreCust: 0.000 X-Origin-Country: SE X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-BeenThere: bug-gnu-emacs@gnu.org List-Id: "Bug reports for GNU Emacs, the Swiss army knife of text editors" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Original-Sender: "bug-gnu-emacs" Xref: news.gmane.io gmane.emacs.bugs:237531 Archived-At: 21 juli 2022 kl. 03.43 skrev Po Lu : > Which is the obvious use? For compatibility with programs (not > necessarily within Emacs) that expect different values based on the > number of VALBITs in the Emacs machine file? Honestly I don't know. Even before Emacs 27, `lsh` seems a bit = questionable since the width is both platform-dependent and unlike C, = say, isn't a particularly useful size. It doesn't correspond to anything = in hardware, isn't a power of two or anything like that. It could be code that expects (lsh x -29) to return the sign bit as 1 or = 0, as some kind of 'optimisation', what do I know. Also see bug#32463 for some discussion about lsh during the transition = to bignums. Basically everyone agreed that it's useless but that it = probably needs to be kept for compatibility in some way.