Received-SPF: pass (google.com: domain of linux-kernel+bounces-23068-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45d1:ec00::1 as permitted sender) client-ip=2604:1380:45d1:ec00::1;
Precedence: bulk
MIME-Version: 1.0
References: <152261521484.30503.16131389653845029164.stgit@warthog.procyon.org.uk>
 <3465e0c6-f5b2-4c42-95eb-29361481f805@zytor.com> <de221edb-6d12-4bef-97a7-4ab4c2381bfc@nvidia.com>
In-Reply-To: <de221edb-6d12-4bef-97a7-4ab4c2381bfc@nvidia.com>
From: Dave Airlie <airlied@gmail.com>
Date: Thu, 11 Jan 2024 15:09:02 +1000
Message-ID: <CAPM=9tzNEbJxVtusYLQqvzo14-CW_Nbo65L7Jfb4dF_JM1PBTQ@mail.gmail.com>
Subject: Re: [PATCH 00/45] C++: Convert the kernel to C++
To: John Hubbard <jhubbard@nvidia.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>, David Howells <dhowells@redhat.com>, linux-kernel@vger.kernel.org, 
	pinskia@gmail.com
Content-Type: text/plain; charset="UTF-8"

> There was an effort to address this, and I remember we even tried to use
> it: Embedded C++ [2]. This is very simplistic and completely out of date
> compared to what is being considered here, but it does show that many
> others have had the same reaction: the language is so large that it
> wants to be constrained. We actually wrote to Bjarne Stroustrup around
> that time and asked about both embedded C++ and coding standards, and
> his reaction was, "don't limit the language, just use education instead".
>
> However, in my experience since then, that fails, and you need at least
> coding standards. Because people will use *everything* they have available,
> unless they can't. :)

You don't just need coding standards, you need a compiler that refuses
to compile that stuff.

If you want C++ to do what Rust could do, then you need the compiler
to stop the stupid before you can even write it, otherwise people will
still write the bad stuff and code review won't catch it all.

Can we get memory safety with C++ now? and also stop people coding C++
like it's 1994?

Kernel C has kinda become a thing without enforcing it, but C wasn't
really stopping anything bad, so having C that isn't quite kernel C
get into corners isn't that bad, but introducing C++ without any
history of kernel C++ is just asking for everyone to do their own
special things and defend their usage of every corner of the language
because they wanted to learn it.

Dave.