From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr1-x42d.google.com (mail-wr1-x42d.google.com [IPv6:2a00:1450:4864:20::42d]) by sourceware.org (Postfix) with ESMTPS id C2B423858C50 for ; Thu, 7 Apr 2022 14:04:42 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org C2B423858C50 Received: by mail-wr1-x42d.google.com with SMTP id w4so7970248wrg.12 for ; Thu, 07 Apr 2022 07:04:42 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=ohpUPi9VHOrd2R8k967TJRxOhNTkHzopUPXomCBFmOQ=; b=OelWkXZ5wnA126tWr2yXNklPCUFWmiqmoJpSPuaJL2FW81P/u1V94ZhHlJ3v2I9m0L WYV9qxFYAhO/HJGFoJugZF4PjX2YsJDsDN2ObioerR6n25UAmfo8z6WD8F4G0pgMyp7K cGk5B8f2362AQkxdmMNfcOWh6Xcz8tmyG8cDeV1vQNM1ew8tlQ0L4A+etVNupDpRXCGO SNwD2bEsFZXbt6ZaspBjctAOkC7nZzHJqtEppduSXdLrApB8YHJUHzPuMPJwuI56l9hf s+X9aHxpdUJAA6+u8urcHUgQ+O+xBVyaMHQ4/sNx6qv0AYL1qW++U5mO9r6WP7k1X45s a7Kw== X-Gm-Message-State: AOAM530Qe2qAdfjiD+UBT+utO3sVBvuyL9PT41L2+/3hvfkhR5ADfDI1 qk70giHMtJZ0lXbTCc1DHc5scQbEzWNefNOyxuE= X-Google-Smtp-Source: ABdhPJzNiNAFQxLlG05c8ULT4Gfp+26JKWA6JRzdedSVj/DTf7Pnya6aMwZpZP4hIF/8EfIrxUmbdrIX+ELZDQZsde4= X-Received: by 2002:a5d:5482:0:b0:206:b5c:ef4d with SMTP id h2-20020a5d5482000000b002060b5cef4dmr10734625wrv.152.1649340281514; Thu, 07 Apr 2022 07:04:41 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Jonathan Wakely Date: Thu, 7 Apr 2022 15:04:28 +0100 Message-ID: Subject: Re: libstdc++.so.0.29 contains undefined reference to libiconv To: Yubin Ruan Cc: "libstdc++" X-Spam-Status: No, score=-1.0 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, FREEMAIL_FROM, HTML_MESSAGE, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.29 X-BeenThere: libstdc++@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libstdc++ mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 07 Apr 2022 14:04:53 -0000 On Thu, 7 Apr 2022, 14:21 Yubin Ruan, wrote: > On Thu, Apr 7, 2022 at 5:02 PM Jonathan Wakely > wrote: > > > > > > > > On Thu, 7 Apr 2022, 03:38 Yubin Ruan via Libstdc++, < > libstdc++@gcc.gnu.org> wrote: > >> > >> Hi, > >> > >> I compile GCC 11.2 and get a libstdc++.so.6.0.29 (installed in > >> "/usr/local/mygcc/lib64/") but this shared lib contains undefined > >> reference to libiconv_*. > >> > >> When I compile a hello world program using gcc11.2, I get the following > error: > >> > >> > /usr/local/mygcc/bin/g++ -Wall -std=c++17 hw.cc -o hw > >> > /usr/local/mygcc/bin/../lib/gcc/x86_64-pc-linux-gnu/11.2.0/../../../../lib64/libstdc++.so: > >> undefined reference to `libiconv' > >> > /usr/local/mygcc/bin/../lib/gcc/x86_64-pc-linux-gnu/11.2.0/../../../../lib64/libstdc++.so: > >> undefined reference to `libiconv_close' > >> > /usr/local/mygcc/bin/../lib/gcc/x86_64-pc-linux-gnu/11.2.0/../../../../lib64/libstdc++.so: > >> undefined reference to `libiconv_open' > >> collect2: error: ld returned 1 exit status > >> > >> Adding a "-liconv" flag will help this program compile. > >> > >> From ldd's output, the libstdc++.so does not has any dynamic reference > >> to libiconv; > >> > >> > ldd /usr/local/mygcc/lib64/libstdc++.so.6.0.29 > >> linux-vdso.so.1 => (0x00007ffce1fea000) > >> libm.so.6 => /lib64/libm.so.6 (0x00007fefc74b8000) > >> libc.so.6 => /lib64/libc.so.6 (0x00007fefc70e9000) > >> /lib64/ld-linux-x86-64.so.2 (0x00007fefc7bd1000) > >> libgcc_s.so.1 => > >> /usr/local/$INSTALL_PREFX/lib64/libgcc_s.so.1 (0x00007fefc6ed1000) > >> > >> But from nm 's output, there are indeed undefined reference to libiconv* > >> > >> > nm -D /usr/local/mygcc/lib64/libstdc++.so.6.0.29 |grep -i iconv > >> U libiconv > >> U libiconv_close > >> U libiconv_open > >> > >> I already have libiconv installed under /usr/local when compiling > >> GCC11.2, but this does not seems to help; > > > > > > It doesn't help because that is the cause of the problem. > > > > Glibc defines the iconv routines that libstdc++ needs, and so you should > not use libiconv on Linux systems using Glibc. > > > So remove all libiconv libs and headers, and recompile GCC will be > fine? Yes. Does it require any more configuration? > No. > How do I make sure that the configuration is correct? > Check the config.log in the $TARGET/libstdc++-v3 build directory, it think it should say where iconv is found. > > >> And by the way, libiconv seems to only provide dynamic lib; there is > >> no libiconv.a; > >> > >> > >> Previously I have GCC10.2 compiled & installed. The libstdc++.so.0.28 > >> also contains undefined ref to libiconv* > >> > >> > nm -D /usr/local/mygcc/lib64/libstdc++.so.6.0.28 |grep -i iconv > >> U libiconv > >> U libiconv_close > >> U libiconv_open > >> > >> but compiling with libstdc++.so.6.0.28 does NOT require "-liconv". > >> > >> So, is there anything that I missed when compiling GCC11.2 which can > >> remove unnecessary dependency of libiconv ? > >> > >> Thanks, > >> Yubin >