From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Andrea Corallo via "Emacs development discussions." Newsgroups: gmane.emacs.devel Subject: Re: Native compilation: the bird-eye view Date: Mon, 24 Aug 2020 14:09:55 +0000 Message-ID: References: <83o8qocd32.fsf@gnu.org> <838shrdb1c.fsf@gnu.org> <837dxbd93b.fsf@gnu.org> Reply-To: Andrea Corallo Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="4770"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.3 (gnu/linux) Cc: Andrea Corallo via "Emacs development discussions." , Eli Zaretskii , Paul Eggert To: Stefan Monnier Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Mon Aug 24 16:10:47 2020 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 1kADBO-00016i-5R for ged-emacs-devel@m.gmane-mx.org; Mon, 24 Aug 2020 16:10:46 +0200 Original-Received: from localhost ([::1]:48268 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kADBN-0006um-7u for ged-emacs-devel@m.gmane-mx.org; Mon, 24 Aug 2020 10:10:45 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:37514) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kADAr-0006MD-AN for emacs-devel@gnu.org; Mon, 24 Aug 2020 10:10:13 -0400 Original-Received: from mx.sdf.org ([205.166.94.24]:63390) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kADAo-0008Eu-Ei; Mon, 24 Aug 2020 10:10:12 -0400 Original-Received: from mab (ma.sdf.org [205.166.94.33]) by mx.sdf.org (8.15.2/8.14.5) with ESMTP id 07OE9tqZ002365; Mon, 24 Aug 2020 14:09:55 GMT In-Reply-To: (Stefan Monnier's message of "Mon, 24 Aug 2020 09:31:53 -0400") Received-SPF: pass client-ip=205.166.94.24; envelope-from=akrl@sdf.org; helo=mx.sdf.org X-detected-operating-system: by eggs.gnu.org: First seen = 2020/08/24 10:10:03 X-ACL-Warn: Detected OS = ??? 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: 2.1.23 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:254181 Archived-At: Stefan Monnier writes: >>> What I was thinking of doing was: when we generate a new .elc file, just >>> before saving the file over the old .elc file, we compute the hash of the >>> old .elc file and erase any matching .eln file. >> >> Remeber ATM the input to the ashing is the .el content and not the .elc, >> this motivated by: > > Hmm... > >> - The .elc may not capture all the input to the compilation that have >> an effect on the native code generation (I don't have a working >> example for this is just a suspect). > > The problem is the opposite: it's the .el file which doesn't > account for the complete information (e.g. you may have to recompile > a .el file even if it hasn't changed, because some of the macros it > uses have been modified). > > The .elc files are less affected by such problems. Very good point. Considering the two problems: 1 having a way to identify the eln filename from source or bytecode file 2 prevent dlopen to be called two times with the same filename (before the initial returned handler is closed). I believe we could work around ourself problem 2 identifying the specific condition that is: we are loading an eln filename that is currently dlopend. In this case we could temporary rename the eln just for having it loaded correctly. If we do this we solve 2 and reloading always works, 1 should be we already solved. How does it sounds? Andrea -- akrl@sdf.org