From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.zytor.com (terminus.zytor.com [198.137.202.136]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CB7594A14 for ; Fri, 12 Jan 2024 02:24:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=zytor.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=zytor.com Authentication-Results: smtp.subspace.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=zytor.com header.i=@zytor.com header.b="X7Ula3Au" Received: from [IPV6:2601:646:8002:4641:eb14:ad94:2806:1c1a] ([IPv6:2601:646:8002:4641:eb14:ad94:2806:1c1a]) (authenticated bits=0) by mail.zytor.com (8.17.2/8.17.1) with ESMTPSA id 40C2NFj0041670 (version=TLSv1.3 cipher=TLS_AES_128_GCM_SHA256 bits=128 verify=NO); Thu, 11 Jan 2024 18:23:16 -0800 DKIM-Filter: OpenDKIM Filter v2.11.0 mail.zytor.com 40C2NFj0041670 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zytor.com; s=2023121201; t=1705026198; bh=gEL02qJ+kf4rmTWjTkIkdSy7bQtlOufhbVEFlnTcpyw=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=X7Ula3AuasMk3h8B+YBe3xqBoqgSzW2ZArYwMqHmPfAT4pVyO+LxLybF/itpYt6Pc AFKoH8feZ5PV8DY/SsbfpcEydX/sluG85FSXmqiPB1WvVhXkBMAOd0PqgEjA4WahIU nbWsNMufkrEJBM7rCH6E2jhajBrGA3dirrzCUtJGVh0xM8V+H+aPGkd5Q/vTaVPSlK xDrOiJDXFRavQ7QlhLd2T5M9Cr3nBkcEbtIfqTgFv54nXssEpsj8qImuh4Rh/gvpBH UMDYDjNIe5hVqtfhI841Rn6yaceEWGShFMmnMk7KadVbc+zURUGluEfwd18PZWWzIO R5nWUEmEMfuqA== Message-ID: Date: Thu, 11 Jan 2024 18:23:10 -0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 00/45] C++: Convert the kernel to C++ Content-Language: en-US To: "Theodore Ts'o" , Neal Gompa Cc: Jason Gunthorpe , jirislaby@kernel.org, dhowells@redhat.com, linux-kernel@vger.kernel.org, pinskia@gmail.com, kent.overstreet@linux.dev References: <938ebce3-74c5-4fcf-9de3-849271d3581d@kernel.org> <20240110130456.142763-1-neal@gompa.dev> <20240110155233.GA623732@nvidia.com> <20240110175755.GC1006537@mit.edu> From: "H. Peter Anvin" In-Reply-To: <20240110175755.GC1006537@mit.edu> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 1/10/24 09:57, Theodore Ts'o wrote: > On Wed, Jan 10, 2024 at 11:25:29AM -0500, Neal Gompa wrote: >> >> For what it's worth, I'm totally in favor of C++20 as well. I've >> mostly written C++17 as of late and it is really nice to me, but I'm >> genuinely excited about C++20 and newer revisions. >> >> I also think that Linux adopting C++ and intentionally adopting safety >> features that exist and are being added to C++ over time would also >> further encourage the ecosystem to use them as well as make the Linux >> codebase much easier to work with. > > Can someone speak to whether the C++ standards committee and C++ > compiler implementations are more or less unreasonable compared to > their C counterparts regarding compilers being able to arbitrary > statement reordering, or other random futzing all in the name of > better benchmarks, but which make life a living nightmware for honest > kernel developers? > I suspect that the gcc and clang developers are more motivated these days about such issues since they are now using C++ as their own implementation language. I had a member of the C++ standards committee reach out to me already, and I'm going to have a discussion with him next week. I have a lot more to say in response to all the (excellent!) comments, but I'm about to leave for a long birthday weekend, so my apologies if I don't get back to things until next week. -hpa