From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS22989 209.51.188.0/24 X-Spam-Status: No, score=-3.8 required=3.0 tests=AWL,BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,RCVD_IN_DNSWL_MED,RCVD_IN_MSPIKE_H4,RCVD_IN_MSPIKE_WL, SPF_HELO_PASS,SPF_PASS shortcircuit=no autolearn=unavailable autolearn_force=no version=3.4.2 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dcvr.yhbt.net (Postfix) with ESMTPS id 662B41F5AE for ; Tue, 27 Apr 2021 23:23:01 +0000 (UTC) Received: from localhost ([::1]:39172 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lbX2i-0004Hc-8U for normalperson@yhbt.net; Tue, 27 Apr 2021 19:23:00 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:42898) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lbX2e-0004HI-Rg for bug-gnulib@gnu.org; Tue, 27 Apr 2021 19:22:56 -0400 Received: from mo4-p01-ob.smtp.rzone.de ([85.215.255.51]:20790) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lbX2c-0007cD-TE for bug-gnulib@gnu.org; Tue, 27 Apr 2021 19:22:56 -0400 ARC-Seal: i=1; a=rsa-sha256; t=1619565765; cv=none; d=strato.com; s=strato-dkim-0002; b=E46lTazaXw4igh/VGp2VRf2oRL0UyQDAUzquVHazCiT+ynVgk643T8rczUCSgvIfh5 KWFu0upH7s3BCfyZ63+blbYn7lR8IfeDx0uwARX7aNOcgXkdWN3b9h7aftVjJWgsqZqQ M2KtVQRSL55QzCtAjCJ1q1Vr3ojkX+fdF4MmXhuAO1aec4SsZpg4D8FW7usUTRVxrr5g H9vmADsyhV+Rw5Jn9zyldvOYefZFPciZqQvhTC5FCvbR8084S1dqw9hcvkCIysb3poWx ParHIrqwi7FvucbE/OGQ8Xcf53KzB0+gG36XqA9x3IdZMxgv3v2AIXa88YfF7xhJPaNA hVuA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; t=1619565765; s=strato-dkim-0002; d=strato.com; h=References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From:Cc:Date: From:Subject:Sender; bh=pfHmIynSU6cpovbPYgLjJgg7+VMv+psD+QwxoR3g08c=; b=mXGG6NzhiROV6ijs2iCbxgD+k6zuzECurBQ0siXcCAiZTSClVcyUuyZ3cEBAEIIQH1 0E7Ndu85AIFIsOyDP9938yZ/fQe1lMDGJi4bMLYCQSq9k7Ee7fTHeAj/yt4ylVqxlqpl sgNzYmRC9hobSR3gdsRCsuKj44SHrQRkFWjXd+MB+HK2/JDpEZFIj/yRZEGdMCcWYRun pJP1hh5tK4/BLYm51ghy+Nb6QlqTlfQtCBNngLxymMA+KrbGsrIvY8LKa3mdgTRSmND5 g7H8u/f8D/BAoskJyAw9lKOX4xBYBz1dzBQPqyegxNoKlSbr7/QWGDb4bXV9RJj1lHfT SHoQ== ARC-Authentication-Results: i=1; strato.com; dkim=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; t=1619565765; s=strato-dkim-0002; d=clisp.org; h=References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From:Cc:Date: From:Subject:Sender; bh=pfHmIynSU6cpovbPYgLjJgg7+VMv+psD+QwxoR3g08c=; b=KSQ5C+VWnTHcVdjCIPpfXt0OBQ1RUXUQbh7s6PI2foj/SfkFIEegTjT7FhEhsBIRXl b/cEkLz23lY3UnJk629+6vFzO7xppfAqjJsJuk0klQLqnvHWRMdysl0GOwRgPz556cjB WyetdjFwZ0dCZ9B11TIDxYPb6gchQTzdC1wQcS4c8pVR5YnI5ummksSqNnYUZhEE3KMB Af297iyUA1AvG//0jh3NMjzCooyQjGHLskQ7nN+Tkx9DChlAmar0ZlROc81V9yhJdr0P JXXqoB6W3XPyOUkuzwJ673XbhgpYzRjJHTHOa7PoFgujydskoyLK9GFsb6tlEnf0GAI/ GkPQ== Authentication-Results: strato.com; dkim=none X-RZG-AUTH: ":Ln4Re0+Ic/6oZXR1YgKryK8brlshOcZlIWs+iCP5vnk6shH+AHjwLuWOHqf3z5NW" X-RZG-CLASS-ID: mo00 Received: from bruno.haible.de by smtp.strato.de (RZmta 47.25.2 DYNA|AUTH) with ESMTPSA id 905ad3x3RNMi3Ou (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (curve X9_62_prime256v1 with 256 ECDH bits, eq. 3072 bits RSA)) (Client did not present a certificate); Wed, 28 Apr 2021 01:22:44 +0200 (CEST) From: Bruno Haible To: bug-gnulib@gnu.org Subject: Re: Undefined use of weak symbols in gnulib Date: Wed, 28 Apr 2021 01:22:44 +0200 Message-ID: <3329251.x8xr5TbW7N@omega> User-Agent: KMail/5.1.3 (Linux/4.4.0-206-generic; KDE/5.18.0; x86_64; ; ) In-Reply-To: <87fszc8a1z.fsf@igel.home> References: <87o8e0p92r.fsf@oldenburg.str.redhat.com> <87fszc8a1z.fsf@igel.home> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Received-SPF: none client-ip=85.215.255.51; envelope-from=bruno@clisp.org; helo=mo4-p01-ob.smtp.rzone.de X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-0.001, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_PASS=-0.001, SPF_NONE=0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: bug-gnulib@gnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Gnulib discussion list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Florian Weimer , libc-alpha@sourceware.org, Andreas Schwab , binutils@sourceware.org Errors-To: bug-gnulib-bounces+normalperson=yhbt.net@gnu.org Sender: "bug-gnulib" Andreas Schwab wrote: > It is likely that the use of weak pthread symbols is not confined to > gnulib. Yes. Between 2000 and 2010 I heard a couple of times "Multithreading support is only available through libpthread. It is a common technique to use weak symbols to distinguish a program linked with -lpthread from a program not linked with -lpthread (and such a program is single-threaded)". Also, people were saying "dlopen of libpthread does not work" [1][2]. Bruno [1] https://jmmv.dev/2004/11/dynamic-open-of-libpthread-considered.html [2] https://sourceware.org/bugzilla/show_bug.cgi?id=18192