From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-yb1-xb32.google.com (mail-yb1-xb32.google.com [IPv6:2607:f8b0:4864:20::b32]) by sourceware.org (Postfix) with ESMTPS id A10E73858D35 for ; Thu, 16 Mar 2023 10:59:53 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org A10E73858D35 Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=gmail.com Received: by mail-yb1-xb32.google.com with SMTP id e65so1322989ybh.10 for ; Thu, 16 Mar 2023 03:59:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; t=1678964393; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=6s+c2ww4IlOrSZ8BQNvn8X/vdzZ0HyXilXhND9uHiMY=; b=mj5kxc6Yoc7lRmnjJfwjHZpeHAwp//U6qFAum2P3ddNnHL8YMdMzpiUJ7iYLVqMV2N Z+2JhbJNr7iOBNH7RZ3RAZqInXWV8KjhYavYCpj0haZbdkT/0rtUrjMqLB9Zrc4uPZ75 CY5M/vVd2fHF5SKhQsWUqD4nLxhD1bSRT44p5ws3+0YaRWb+gvTEKUCD9diOM7nq/I77 pzRmah2QnJjpsqkYPbW+92qY4IWmRg6Qk9dKnxYy5HsH1vJDItlJVNK1SHNTu4XVdKhd XmmkEHk1d2eIDFFqC0FBz5pQMxU2i8RHuzt/KEWTd0ZB9c79BKVWqo6vVvoRDcO8JzOZ 5osg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1678964393; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=6s+c2ww4IlOrSZ8BQNvn8X/vdzZ0HyXilXhND9uHiMY=; b=LYER18uxCE6wRf9M6uA1BL8RJRiCbOeOEci7vmjSWxeP0m/lsflJySOae/ykOBFfC6 SRwp/D9tKKfTqKI586iQo7p3pSkVZi00RXrAzfDVA4RQfbcv1MXfK6JHb5YIRoRmD6Ai 2Yb003D0v+qEBDGWXFbpwMlcx4ZwJ6o5Iru8Mtpob/lvdaP29XhMFoT72pnO6+LY9P3C jtZ0z9rEnDok49H/3tWLWSXp5TlveeFhhygozjW/GBtTHACeCjH+3eyTgsd+RzMX5Hvd 20UwAuovqSzUBPxqK3XDPKzuDS5QTRFUY7bQlo/ngN5wrwVjmJHuAgJLHbcN3t1bUaQx s/AA== X-Gm-Message-State: AO0yUKWZMZEF6mxKa+/rYvWNN5JnUs0bB+jZDFrGivcH/guFNK6gvl6P tg8WTJZ6yj5JnY6ThDwBS7WpsIQhlSHBvFgRjQOyCzn7R89caQ== X-Google-Smtp-Source: AK7set83OdCNA7sl7J91fz0+oKfTbxtR14PFR18+Pa1kvrWsu3Yl0IMk5IUb/89uwg5mPnc5utqfB/D6CgVJG3oNfeA= X-Received: by 2002:a25:8a8b:0:b0:af6:9419:60bc with SMTP id h11-20020a258a8b000000b00af6941960bcmr13866584ybl.0.1678964392974; Thu, 16 Mar 2023 03:59:52 -0700 (PDT) MIME-Version: 1.0 References: <6c8e0fc6-9e86-6fc7-433f-cf5df16a6b03@linaro.org> <87jzzi14fx.fsf@oldenburg.str.redhat.com> <7d1b9611-13d1-65f0-9b47-0f7d01cec66c@linaro.org> In-Reply-To: <7d1b9611-13d1-65f0-9b47-0f7d01cec66c@linaro.org> From: Abhijit Ray Chaudhury Date: Thu, 16 Mar 2023 16:29:41 +0530 Message-ID: Subject: Re: compiling glibc using -fasynchronous-unwind-tables for arm To: Adhemerval Zanella Netto Cc: Florian Weimer , Adhemerval Zanella Netto via Libc-help Content-Type: multipart/alternative; boundary="0000000000003bdc8a05f7025ce1" X-Spam-Status: No, score=0.4 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 autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: --0000000000003bdc8a05f7025ce1 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hi, I think the problem lies with the precedence of seemingly conflicting CFLAGS "-fasynchronous-unwind-tables -fno-unwind-tables" supplied to my cross toolchain gcc. I compiled a simple C file with " -fasynchronous-unwind-tables" , it generated an undefined symbol " `__aeabi_unwind_cpp_pr0'" although compilation was successful without -static flag. Then I compiled with " -fasynchronous-unwind-tables -fno-unwind-tables", it still generated the undefined symbol " `__aeabi_unwind_cpp_pr0'". It suggests " -fno-unwind-tables" does not stop unwind information in the ELF when I have " -fasynchronous-unwind-tables" . I then compiled with " -funwind-tables -fno-unwind-table", I did not find undefined symbol " `__aeabi_unwind_cpp_pr0'"in the generated ELF. So I will compile glibc with " -funwind-table" instead of " -fasynchronous-unwind-table" and let you know the result. Do you see any problem with this approach ? Thanking You, -Abhijit On Thu, Mar 16, 2023 at 1:22=E2=80=AFAM Adhemerval Zanella Netto < adhemerval.zanella@linaro.org> wrote: > > > On 15/03/23 11:20, Florian Weimer wrote: > > * Adhemerval Zanella Netto via Libc-help: > > > >> And I have tested with both: > >> > >> CC=3D"arm-glibc-linux-gnueabihf-gcc -fasynchronous-unwind-tables" > >> > >> and > >> > >> CC=3Darm-glibc-linux-gnueabihf-gcc CFLAGS=3D"-O2 > -fasynchronous-unwind-tables" > >> > >> I also tested with gcc from ubuntu22 to check if this might something > >> I haven't enabled on my toolchain (since I don't build all languages), > >> but again I did not see any issue. > > > > It probably depends on whether libgcc.a has been built with > > optimizations or not. > > Indeed this looks like > https://sourceware.org/bugzilla/show_bug.cgi?id=3D29621 . > Does the build work if you manually adds the -fasynchronous-unwind-tables > on config.make? > --0000000000003bdc8a05f7025ce1--