From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: changed dlopen flags in dynlib.c, gccemacs crash Date: Sun, 06 Mar 2022 17:32:36 +0200 Message-ID: <834k4bgkq3.fsf@gnu.org> References: <83tufjw848.fsf@gnu.org> <83lf0uuqaq.fsf@gnu.org> <83o85nr1mm.fsf@gnu.org> Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="13666"; mail-complaints-to="usenet@ciao.gmane.io" Cc: emacs-devel@gnu.org, silent2600@gmail.com, akrl@sdf.org To: Philipp Stephani Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Sun Mar 06 16:33:56 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 1nQstP-0003IZ-EU for ged-emacs-devel@m.gmane-mx.org; Sun, 06 Mar 2022 16:33:55 +0100 Original-Received: from localhost ([::1]:58078 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nQstO-0008Df-44 for ged-emacs-devel@m.gmane-mx.org; Sun, 06 Mar 2022 10:33:54 -0500 Original-Received: from eggs.gnu.org ([209.51.188.92]:41314) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nQssO-0007We-Fe for emacs-devel@gnu.org; Sun, 06 Mar 2022 10:32:52 -0500 Original-Received: from [2001:470:142:3::e] (port=49008 helo=fencepost.gnu.org) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nQssM-00081g-2v; Sun, 06 Mar 2022 10:32:50 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=gnu.org; s=fencepost-gnu-org; h=References:Subject:In-Reply-To:To:From:Date: mime-version; bh=qMjPd/M3I8V2xo2bvLtrToj5mMrIWl1Lvm2WU+ro08Y=; b=e0yLQKiO+FlB IUds8OOSsLkcHn/y1NSH/swuit8Wr88awBq5d7o+ynMbWEwEDoN2J0eF6LB4e0wAZM0A7iLseQBsy rLFFNR/82cgwaV9f8mBRIQ3tMn07EnpgHlnv9ZHwEf/pJ+ggrfv+VnRCsB2CG6U3qaj2d14DA8xBn nwgSXCK2u0aJ7sIya0J84RXRX1TXpRhi7xfJa8BC07CD+dmPvlhLp2hV+Jz8aAvjESbK30Q7Pxz7V wENKPpGV/TzQdShav5VnQbUiL4+dBgunrv9p5pJ+Demw3h/Q0P0CteFbJRkZsGsd05YQY0Cg8wnbi zI38Kh5VK/vHrDp5GgvmWQ==; Original-Received: from [87.69.77.57] (port=1493 helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nQssL-0000vG-H1; Sun, 06 Mar 2022 10:32:49 -0500 In-Reply-To: (message from Philipp Stephani on Sun, 6 Mar 2022 15:32:14 +0100) 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:286856 Archived-At: > From: Philipp Stephani > Date: Sun, 6 Mar 2022 15:32:14 +0100 > Cc: Eli Zaretskii , hx , > Emacs developers > > > yes, I think once we have verified the issue is what we suspect we could > > dlopen eln files as before and have RTLD_GLOBAL added for the other > > cases. > > This thread is already quite old, but let me point out that > https://www.akkadia.org/drepper/dsohowto.pdf warns very strongly > against using RTLD_GLOBAL (section 1.5.4), and I don't see a strong > reason to not heed that warning. So I'd recommend removing RTLD_GLOBAL > again. We added it for a reason, and I don't see anything in Ulrich Drepper's paper that could affect Emacs modules badly enough to back up on this. That said, I don't see myself an expert on this stuff, so if enough people here think it will have adverse effect on Emacs, I'm okay with removing that flag, provided that we see some detailed explanations of how this could be detrimental to use of Emacs modules.