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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Wed, 7 Jul 2021 11:57:19 -0700
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Subject: Re: [TECH TOPIC] Rust for Linux
To: Bart Van Assche <bvanassche@acm.org>
Cc: Stephen Hemminger <stephen@networkplumber.org>, Roland Dreier <roland@kernel.org>, 
	Linus Walleij <linus.walleij@linaro.org>, Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>, 
	ksummit@lists.linux.dev
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On Tue, Jul 6, 2021 at 7:41 PM Bart Van Assche <bvanassche@acm.org> wrote:
>
> As a sidenote, I'm surprised that C++ is not supported for Linux kernel
> code since C++ supports multiple mechanisms [..]

You'd have to get rid of some of the complete garbage from C++ for it
to be usable.

One of the trivial ones is "new" - not only is it a horribly stupid
namespace violation, but it depends on exception handling that isn't
viable for the kernel, so it's a namespace violation that has no
upsides, only downsides.

Could we fix it with some kind of "-Dnew=New" trickery? Yes, but
considering all the other issues, it's just not worth the pain. C++ is
simply not a good language. It doesn't fix any of the fundamental
issues in C (ie no actual safety), and instead it introduces a lot of
new problems due to bad designs.

            Linus