From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by sourceware.org (Postfix) with ESMTPS id AD9F6384D169 for ; Thu, 15 Feb 2024 16:07:33 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org AD9F6384D169 Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=redhat.com ARC-Filter: OpenARC Filter v1.0.0 sourceware.org AD9F6384D169 Authentication-Results: server2.sourceware.org; arc=none smtp.remote-ip=170.10.133.124 ARC-Seal: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1708013255; cv=none; b=mAcsAnaX96szcdL89T/J0gg/cjd+m/XlVs1TM5/GEnfHoiyA76UDnXxHkrrqqZKiQifFFf41VLWE8H81sORBvE3BEVb0pYoGiZgFCYuRkPq8MWDNfwNvIqgiAvhZdKeusPoYUFH+7Nq1RIgfeacfyyIwW1VtbgKSM/6V+TA9BFA= ARC-Message-Signature: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1708013255; c=relaxed/simple; bh=bL5fNB8EVxi4NZg/IwYInzGWal0YEZWwZ2MvekrTEVk=; h=DKIM-Signature:From:To:Subject:Date:Message-ID:MIME-Version; b=Lzk33Imm7z/5P/dLK7WdUbfSbIPe5stgjJW2IOimzdupTOp7klA4a8Y6ckAOO9c5iZ62L6PA3Yf85s4h0bFujBKg7/a6qIPiOInsM3tHF9mqlvt+NMGYcM6eEaF3Qud8pvUsGUgQOntNnxWNxakcCJkvrPk1ZQQjqtlDB4SMpfg= ARC-Authentication-Results: i=1; server2.sourceware.org DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1708013253; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=aMpLENF7ms83jnPUp9Etp/ZLARe8oF5z65hbn2tE0VE=; b=EFiqZYH9JDHLz6gB+uobogIqi/4CMYWT5SSs7idVdZJ28IL5AdG/WGe13H9+ctvLTnlohv PHElSxgKmhG5lkakPuMJWq0oFu7+JYlJeZW5GCJ4sbkhJ9awTVR43gEXhyDtEljl2uBCPh QNnXYgl7ALnc9RMpQh2ms8GBEEjmxy8= Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-124-66IzjlcIN3iufhA2Cie6AA-1; Thu, 15 Feb 2024 11:07:30 -0500 X-MC-Unique: 66IzjlcIN3iufhA2Cie6AA-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id E50C2280A9AD; Thu, 15 Feb 2024 16:07:29 +0000 (UTC) Received: from oldenburg.str.redhat.com (unknown [10.39.192.50]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 04CF2492BC6; Thu, 15 Feb 2024 16:07:28 +0000 (UTC) From: Florian Weimer To: Sam James Cc: gcc-patches@gcc.gnu.org, Gerald Pfeifer Subject: Re: [PATCH] Notes on the warnings-as-errors change in GCC 14 References: <87v876ssxg.fsf@oldenburg.str.redhat.com> <87cyt7toso.fsf@gentoo.org> Date: Thu, 15 Feb 2024 17:07:27 +0100 In-Reply-To: <87cyt7toso.fsf@gentoo.org> (Sam James's message of "Thu, 08 Feb 2024 07:04:13 +0000") Message-ID: <87le7laeyo.fsf@oldenburg.str.redhat.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.3 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.9 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=-5.0 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,KAM_NUMSUBJECT,RCVD_IN_DNSWL_NONE,RCVD_IN_MSPIKE_H4,RCVD_IN_MSPIKE_WL,SPF_HELO_NONE,SPF_NONE,TXREP,T_SCC_BODY_TEXT_LINE 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: * Sam James: > It's fine if you leave this out, but consider mentioning the common > pitfall of autoconf projects not including config.h consistently before > all inclues. We could also mention AC_USE_SYSTEM_EXTENSIONS. I added:=20 =E2=80=9C Alternatively, projects using using Autoconf could enable AC_USE_SYSTEM_EXTENSIONS. =E2=80=9D inclusion is a larger issue, I think, best addressed by future diagnostics. >> +

>> +When building library code on GNU systems, it was possible to call >> +undefined (not just undeclared) functions and still run other code in >> +the library, particularly if ELF lazy binding was used. Only >> +executing the undefined function call would result in a lazy binding >> +error and program crash. > > Maybe explicitly refer to the bfd linker's relaxed behaviour so it > sounds less mysterious. Like this? =E2=80=9C

When building library code on GNU systems, it was possible to call undefined (not just undeclared) functions and still run other code in the library, particularly if ELF lazy binding was used. Only executing the undefined function call would result in a lazy binding error and program crash. =E2=80=9D Thanks, Florian