From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oo1-xc35.google.com (mail-oo1-xc35.google.com [IPv6:2607:f8b0:4864:20::c35]) by sourceware.org (Postfix) with ESMTPS id BAF193847718 for ; Wed, 3 Apr 2024 14:46:33 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org BAF193847718 Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=gmail.com ARC-Filter: OpenARC Filter v1.0.0 sourceware.org BAF193847718 Authentication-Results: server2.sourceware.org; arc=none smtp.remote-ip=2607:f8b0:4864:20::c35 ARC-Seal: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1712155595; cv=none; b=B9LzbzoU68m9tEOgl/kfxT7k1mqWAO2ekE8khpG3+er3+eOFGe/sq83JKw6PH7WmzYM05bez2PfzdWosYsNwbUr2f+bvYIML8BqnA9noUUfBgiZrQuzQP/WySKs4lxaUsXO5g1SM16jJuqbtBraUCZdtk1wvcOmj9OavCW7lZZk= ARC-Message-Signature: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1712155595; c=relaxed/simple; bh=23YSbW1EEFqo+rJIPMNke0IlwXoGIosOIaA0Ew0LSfo=; h=DKIM-Signature:MIME-Version:From:Date:Message-ID:Subject:To; b=fox8qdld+T2XqSHw9nW3g9Kax5sTJXtdag0ELSN+KqmoTCsq9yL7MwGni79CFPsAsTXmnMePBFMxPfkqdyRRD0N7KtC6TlHXzq/ylh9mzoMdsa1/44xUoGAnosHgY1hWkW/+DhjEaHeHC9UqvL1PN/NKY+M7WIrZbzU7NIuz9E4= ARC-Authentication-Results: i=1; server2.sourceware.org Received: by mail-oo1-xc35.google.com with SMTP id 006d021491bc7-5a9d295d91eso106343eaf.2 for ; Wed, 03 Apr 2024 07:46:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1712155593; x=1712760393; darn=gcc.gnu.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :reply-to:in-reply-to:references:mime-version:from:to:cc:subject :date:message-id:reply-to; bh=21eLxaNsqn56YcIxmLnnT3S0wRDUc0aS/RryFt156zk=; b=MkYl906OqftkhrqDZW+j2m+9+zrMZ3bXz2z1c0+jS982Al3tnm1v5o8/YGyOrRvDk8 s4CaCKgUXK0tV07OGtu2cj39ZMPawO8Q24PB90SI6EeXxItbFS/aCcIDIiT1nm2lPcVz H1E80zrEXEMkRKMdJxKnYRSYmIyqUoD/MboihIiTWESBse2PvA83kt8QMO/kxrd4y7Ux U8an83b4S2+NBj55JnwA4WW/TQahYLsi7XRvrPoA6HYhwNpVwCPLuObVssymzG/VX1Oe Q3oQAWA2jThfVLMa4giZUk7aFPGI/vciDOueXDts8wOL0+fTEQlpWSF8j4VWRD4/hOWs gzzg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1712155593; x=1712760393; h=content-transfer-encoding:cc:to:subject:message-id:date:from :reply-to:in-reply-to:references:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=21eLxaNsqn56YcIxmLnnT3S0wRDUc0aS/RryFt156zk=; b=TrTOy3i2NDOlbhzkhqirGuJRpLq/HIx+V1oesoivDlhs+YwGh+oSBW6Lpad27bRUeS cnph9mKs1kz8DYGvtEw6IPdTI922ZbYVNLmzSAguYwYoHF+lh3xECFYwduZzHs0KgxK1 3vZCCb7HmafGEsHVSnM3FMFldh+MmsaYrSrlDszXveBfJ2Su74MJm5dX6meb+JEfPmMr xSJX8QJeWZ9ty1VL2+lyNVesRrjGQnbVSqFA7yAaqjRw+LqP27KTKYd86utZkNeJKKGw s8zJ3MbaIsB4Ijif1cVTqTdirlAjY48Sri/8UbQfQ+xxCF1CoI7LuSdLIjNuqKDnGUPr 7h0g== X-Forwarded-Encrypted: i=1; AJvYcCWd40odILeXXs/H/HJBgGR42Yr2CPByWVHoh6+iZeyikOFP+efzcZdwA5iuCMyyAGAyialHnzK2sSiPb2u+Lmk= X-Gm-Message-State: AOJu0Yw+Hy5MVNbdvDBBo9bNfPQjDkxTmNuHzFaaCQ0lStmCEBT63VkK IgX8bo1x1SyOjtGtMLLp+HLMKe3gpwM9VAAV5WkvBvSH4VG4kpPTyjn9RJqgJ7Pyn2rTxXdGWuA R8Igm+Hi+uGMf55b/XqpC2QCKFmE= X-Google-Smtp-Source: AGHT+IHyAUQO6yYbgPMAXBZqKE+H9Vs8oxd/jXA6IeyVV6HnaafPEvIKUCbKxlMceWO1JHB8InZdqrZ/qXHA4asxiHk= X-Received: by 2002:a05:6820:270a:b0:5a5:2105:f209 with SMTP id db10-20020a056820270a00b005a52105f209mr16507263oob.6.1712155593056; Wed, 03 Apr 2024 07:46:33 -0700 (PDT) MIME-Version: 1.0 References: <20240329203909.GS9427@gnu.wildebeest.org> <20240401150617.GF19478@gnu.wildebeest.org> <12215cd2-16db-4ee4-bd98-6a4bcf318592@cs.ucla.edu> <6239192ba9ff8aad0752309a54b633dc75a57c77.camel@tugraz.at> <8e877d2f-01e0-c786-dea5-265edbdc0c07@suse.de> In-Reply-To: Reply-To: noloader@gmail.com From: Jeffrey Walton Date: Wed, 3 Apr 2024 10:46:21 -0400 Message-ID: Subject: Re: Sourceware mitigating and preventing the next xz-backdoor To: Martin Uecker Cc: Michael Matz , Ian Lance Taylor , Paul Koning , Paul Eggert , Sandra Loosemore , Mark Wielaard , overseers@sourceware.org, gcc@gcc.gnu.org, binutils@sourceware.org, gdb@sourceware.org, libc-alpha@sourceware.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=-0.5 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_FROM,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: On Wed, Apr 3, 2024 at 10:33=E2=80=AFAM Martin Uecker via Gdb wrote: > > Am Mittwoch, dem 03.04.2024 um 16:00 +0200 schrieb Michael Matz: > > [...] > > (And, FWIW, testing for features isn't "complex". And have you looked = at > > other build systems? I have, and none of them are less complex, just > > opaque in different ways from make+autotools). > > I ask a very specific question: To what extend is testing > for features instead of semantic versions and/or supported > standards still necessary? This seems like a problematic approach > that may have been necessary decades ago, but it seems it may be > time to move on. I think it is still needed. As a first example, Musl does not define preprocessor macros to identify itself. The project feels features should be probed at build time with a tool like Autoconf. As a second example, activating code paths, like AVX2 and AVX512, requires ensuring the compiler actually supports the ISA. Building a program on an older distribution with an older compiler could run afoul. Jeff