From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C0CF1C33CB3 for ; Tue, 28 Jan 2020 10:05:05 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8C05124686 for ; Tue, 28 Jan 2020 10:05:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="ZsZa/zlU" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8C05124686 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:56312 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iwNk0-0003Fn-Ou for qemu-devel@archiver.kernel.org; Tue, 28 Jan 2020 05:05:04 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:41475) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iwNjF-0002kf-G7 for qemu-devel@nongnu.org; Tue, 28 Jan 2020 05:04:19 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iwNjC-0005SW-MD for qemu-devel@nongnu.org; Tue, 28 Jan 2020 05:04:15 -0500 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:25452 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iwNjC-0005R1-Av for qemu-devel@nongnu.org; Tue, 28 Jan 2020 05:04:14 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1580205853; h=from:from:reply-to: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=ggMU2O5FuN/w4Jfpv2Ow5aDB3X7xp32MfNIxAT+Jiws=; b=ZsZa/zlUCGX43sTi3bGqK2g62Yi9wUzpTCFHe2AiFVSxYMLdcIBxkfTpd4LnLgBfL+xWth WgkD045yIZerr/U4qVwtvGtv/BAn6L/3mHgR3lMqBkWdwGbQKYYffjuZ2FKZeIKN3+w3oU 3runMwestigXaTQX8xmR2kwBYz//wVg= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-428-FnXxB2jcMZyOlNow_MnHSA-1; Tue, 28 Jan 2020 05:04:10 -0500 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 6B15B8010C9; Tue, 28 Jan 2020 10:04:09 +0000 (UTC) Received: from redhat.com (ovpn-112-34.ams2.redhat.com [10.36.112.34]) by smtp.corp.redhat.com (Postfix) with ESMTPS id EED315D9C9; Tue, 28 Jan 2020 10:04:00 +0000 (UTC) Date: Tue, 28 Jan 2020 10:03:56 +0000 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Christophe de Dinechin Subject: Re: Integrating QOM into QAPI Message-ID: <20200128100356.GF1446339@redhat.com> References: <871rrtmkko.fsf@dusky.pond.sub.org> <20200121113224.GD630615@stefanha-x1.localdomain> <87wo9lc4oe.fsf_-_@dusky.pond.sub.org> <20200121143658.GB597037@redhat.com> <871rrs97ld.fsf@dusky.pond.sub.org> MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/1.13.3 (2020-01-12) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-MC-Unique: FnXxB2jcMZyOlNow_MnHSA-1 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 205.139.110.120 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Cc: Kevin Wolf , Peter Maydell , "Denis V. Lunev" , Stefan Hajnoczi , qemu-devel , Markus Armbruster , =?utf-8?Q?Marc-Andr=C3=A9?= Lureau , Paolo Bonzini , John Snow , Dominik Csapak Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Mon, Jan 27, 2020 at 08:05:36PM +0100, Christophe de Dinechin wrote: >=20 >=20 > > On 26 Jan 2020, at 16:04, Peter Maydell wrot= e: > >=20 > > On Sun, 26 Jan 2020 at 08:10, Christophe de Dinechin > > wrote: > >> I=E2=80=99m still puzzled as to why anybody would switch to something = like > >> GObject when there is C++. > >=20 > > I'm fairly strongly against using C++. >=20 > Just to be clear, so am I ;-) >=20 > > C++'s language design > > is an "everything including the kitchen sink, lots of "this > > is here for back compat but it's a bear trap", lots of new > > stuff arriving all the time. >=20 > Actually, the new stuff is not that bad, overall. >=20 > I do agree C++ is an overly complicated language, and that in > practice, there is zero chance of qemu moving to it. But that does > not invalidate my point that creating a class in C++ is easier > than creating a class in any C-based macro-heavy reinvention > of basic OO concepts. >=20 > (I write this after having read Paolo=E2=80=99s response, which points > out IMO better reasons for GObject, which I will discuss there). >=20 > > It's just too big to keep in > > your head all at once. C has its faults, absolutely, but at > > least it tries to be a reasonably sized vaguely coherent > > language. > >=20 > > You'd have more luck persuading me we should move to Rust: > > at least then we'd get some clear benefits (no more buffer > > overrun security bugs) for the upheaval :-) >=20 > This is largely a myth as soon as you need to do =E2=80=9Cyour own stuff= =E2=80=9D. > Example: CVE-2019-18960, https://seclists.org/oss-sec/2019/q4/141. Calling it a "myth" from from that one data point is not really credible. No language is perfect & such that it can eliminate all possible CVEs. Rust *can*, however, eliminate a very large set of bugs which lead to=20 memory corruption in unchecked languages like C/C++. You'll still have CVEs to deal with, but they'll be different classes of bugs, or rare edge cases like the one you show above. Regards, Daniel --=20 |: https://berrange.com -o- https://www.flickr.com/photos/dberrange= :| |: https://libvirt.org -o- https://fstop138.berrange.com= :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange= :|