From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Andrea Corallo Newsgroups: gmane.emacs.devel Subject: Re: Suppressing native compilation (short and long term) Date: Thu, 29 Sep 2022 08:18:08 +0000 Message-ID: References: <87ill8paw7.fsf@trouble.defaultvalue.org> <834jwrig5s.fsf@gnu.org> <83wn9ngvr6.fsf@gnu.org> <83r0zuhgfl.fsf@gnu.org> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="31711"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/29.0.50 (gnu/linux) Cc: rlb@defaultvalue.org, emacs-devel@gnu.org To: Eli Zaretskii Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Thu Sep 29 10:22:15 2022 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 1odooB-00086L-Kr for ged-emacs-devel@m.gmane-mx.org; Thu, 29 Sep 2022 10:22:15 +0200 Original-Received: from localhost ([::1]:41298 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1odooA-0005g5-Ap for ged-emacs-devel@m.gmane-mx.org; Thu, 29 Sep 2022 04:22:14 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:45004) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1odokJ-00039L-IC for emacs-devel@gnu.org; Thu, 29 Sep 2022 04:18:16 -0400 Original-Received: from mx.sdf.org ([205.166.94.24]:50727) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1odokH-0004g6-Ky; Thu, 29 Sep 2022 04:18:15 -0400 Original-Received: from ma.sdf.org (ma.sdf.org [205.166.94.33]) by mx.sdf.org (8.15.2/8.14.5) with ESMTPS id 28T8I88h006895 (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256 bits) verified NO); Thu, 29 Sep 2022 08:18:09 GMT In-Reply-To: <83r0zuhgfl.fsf@gnu.org> (Eli Zaretskii's message of "Thu, 29 Sep 2022 08:56:30 +0300") Received-SPF: pass client-ip=205.166.94.24; envelope-from=akrl@sdf.org; helo=mx.sdf.org X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.29 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:296451 Archived-At: Eli Zaretskii writes: >> From: Andrea Corallo >> Cc: rlb@defaultvalue.org, emacs-devel@gnu.org >> Date: Wed, 28 Sep 2022 21:32:13 +0000 >> >> Eli Zaretskii writes: >> >> >> Yes `native-comp-deferred-compilation' AFAIK does exactly this already, >> >> `native-comp-available-p' is to check if the native compiler is >> >> available (not necessarily the deferred/async mechanism). >> > >> > But then it should disable the trampolines as well, see startup.el. >> >> Not in my opinion, trampolines are not deferred async compilation. >> >> Also as mentioned ATM is not possible to disable trampolines and have a >> fully working native comp Emacs (if we assume primitives can be >> redefined). > > I'm confused. I alluded to this part of startup.el: > > (when (featurep 'native-compile) > (unless (native-comp-available-p) > ;; Disable deferred async compilation and trampoline synthesis > ;; in this session. This is necessary if libgccjit is not > ;; available on MS-Windows, but Emacs was built with > ;; native-compilation support. > (setq native-comp-deferred-compilation nil > comp-enable-subr-trampolines nil)) > > The last part disables trampolines, AFAIU. So what am I missing here? Hi Eli, yes it does, what do you find confusing about this? This is how I see things, we have two compilation mechanisms: 1- Syncronous native compilation. This can be triggered: 1.1- By the user (calling `native-compile'). 1.2- By Emacs in the need of generating a trampoline. 2- Async/deferred/jit (or how we wanna call it), this is triggered automatically when loafing a .elc with no corresponding .eln. We have two customize to control the two automatic mechanisms: `comp-enable-subr-trampolines' gates 1.2, `native-comp-deferred-compilation' gates 2. Indeed `native-comp-available-p' gates all native compilations. Best Regards Andrea