From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Helmut Eller Newsgroups: gmane.emacs.devel Subject: Re: named-let Date: Tue, 12 Jan 2021 10:13:54 +0100 Message-ID: References: <87im86kub6.fsf@logand.com> <86zh1g62zx.fsf@163.com> <875z4385yd.fsf@logand.com> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="5429"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.0.50 (gnu/linux) To: emacs-devel@gnu.org Cancel-Lock: sha1:bfyzgwubyEnyaQeJrV0s7VKFasE= Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Tue Jan 12 10:15:36 2021 Return-path: Envelope-to: ged-emacs-devel@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 1kzFm3-0001Hx-Tl for ged-emacs-devel@m.gmane-mx.org; Tue, 12 Jan 2021 10:15:35 +0100 Original-Received: from localhost ([::1]:48054 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kzFm2-0001bw-Vo for ged-emacs-devel@m.gmane-mx.org; Tue, 12 Jan 2021 04:15:34 -0500 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:58516) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kzFkZ-0000jc-M5 for emacs-devel@gnu.org; Tue, 12 Jan 2021 04:14:03 -0500 Original-Received: from ciao.gmane.io ([116.202.254.214]:34088) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kzFkY-0006MY-Bg for emacs-devel@gnu.org; Tue, 12 Jan 2021 04:14:03 -0500 Original-Received: from list by ciao.gmane.io with local (Exim 4.92) (envelope-from ) id 1kzFkV-000A5f-FD for emacs-devel@gnu.org; Tue, 12 Jan 2021 10:13:59 +0100 X-Injected-Via-Gmane: http://gmane.org/ Received-SPF: pass client-ip=116.202.254.214; envelope-from=ged-emacs-devel@m.gmane-mx.org; helo=ciao.gmane.io X-Spam_score_int: 5 X-Spam_score: 0.5 X-Spam_bar: / X-Spam_report: (0.5 / 5.0 requ) BAYES_00=-1.9, DKIM_ADSP_CUSTOM_MED=0.001, FORGED_GMAIL_RCVD=1, FREEMAIL_FORGED_FROMDOMAIN=0.248, FREEMAIL_FROM=0.001, HEADER_FROM_DIFFERENT_DOMAINS=0.249, NML_ADSP_CUSTOM_MED=0.9, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.23 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-mx.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.io gmane.emacs.devel:262961 Archived-At: On Mon, Jan 11 2021, Stefan Monnier wrote: > I don't know how easy it is to implement for > native-comp. Maybe GCC magically does it for us? GCC can optimize sibling-calls; that's a class of tail-calls where the argument count of the callee and caller are the same. Other tail-calls are difficult to optimize, because most systems prescribe a the caller-pops-arguments calling convention (including the varargs stuff). Last time I checked LLVM, doesn't even optimize sibling-calls. Helmut