From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from localhost (localhost [127.0.0.1]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id EF12226E61 for ; Fri, 23 Aug 2019 17:04:56 -0400 (EDT) Received: from turing.freelists.org ([127.0.0.1]) by localhost (turing.freelists.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Jyfs6tj3Ym_B for ; Fri, 23 Aug 2019 17:04:56 -0400 (EDT) Received: from smtp55.i.mail.ru (smtp55.i.mail.ru [217.69.128.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTPS id ABF0E25DAC for ; Fri, 23 Aug 2019 17:04:56 -0400 (EDT) Subject: [tarantool-patches] Re: [PATCH] build: fix linking with static openssl library References: <3124ad309d395d9fe9581499198bcd2de9c83b3c.1566525651.git.alexander.turenko@tarantool.org> From: Vladislav Shpilevoy Message-ID: <1cf410ba-4709-5a37-24e9-b9d660c01f92@tarantool.org> Date: Fri, 23 Aug 2019 23:07:59 +0200 MIME-Version: 1.0 In-Reply-To: <3124ad309d395d9fe9581499198bcd2de9c83b3c.1566525651.git.alexander.turenko@tarantool.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: tarantool-patches-bounce@freelists.org Errors-to: tarantool-patches-bounce@freelists.org Reply-To: tarantool-patches@freelists.org List-Help: List-Unsubscribe: List-software: Ecartis version 1.0.0 List-Id: tarantool-patches List-Subscribe: List-Owner: List-post: List-Archive: To: Alexander Turenko Cc: tarantool-patches@freelists.org Thanks for the patch! On 23/08/2019 04:08, Alexander Turenko wrote: > System-wide dynamic libraries usually (always?) have NEEDED and RUNPATH > tags in a dynamic section (as `readelf -d /usr/lib/lib<...>.so` shows), > so when we link, say, with libssl.so, which depends on libz.so, a linker > does not complain against unresolved symbols that can be found in Z > library (if it is installed within a system). > > Things are different when we linking with a static library. Say, when we > linking with libssl.a, which contains an unresolved symbol from Z > library, a linker reports an error. It is not possible to store an > information where to find unresolved symbols (NEEDED / RUNPATH) in a > static library (AFAIK). > > We depend on three libraries that are depend on Z library: libcurl, > libssl and libcrypto (two latter are part of OpenSSL). When one of those > libraries is linked statically we should link with libz.so or libz.a > (depending on BUILD_STATIC flag). The patch doing exactly this. > Before this patch we add Z library to OPENSSL_LIBRARIES when > BUILD_STATIC is enabled. It is not quite correct: we should do that when > OPENSSL_USE_STATIC_LIBS is enabled. However we didn't experienced > problems with static linking of libcurl (when BUILD_STATIC is enabled), > because OPENSSL_LIBRARIES is added to CURL_LIBRARIES. This is a kind of > side effect of dependency libcurl on OpenSSL and it is better to add > libz explicitly to CURL_LIBRARIES (and OPENSSL_LIBRARIES) when > appropriate. Is it correct, that all the curl-related changes are just sugar not related to the bug? Because I spent some time on attempts to understand, how is curl related to the problem, but looks like in no way. > > Fixes #4437. > --- > > https://github.com/tarantool/tarantool/issues/4437 > https://github.com/tarantool/tarantool/tree/Totktonada/gh-4437-fix-static-openssl-build-full-ci > > I more or less understood what is going on with all that linking stuff, > but it would be glad if you'll check my wording around this topic. Looks correct. Just a simple problem of a missing library during static linking of a subsystem.