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From:   Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Date:   Mon, 12 Sep 2022 17:18:43 +0100
Message-ID: <CANiq72kZEqAwr_m14mAFjHsFJTLjj7i4He0qyrprubpmBfOFdw@mail.gmail.com>
Subject: Re: [PATCH v9 23/27] Kbuild: add Rust support
To:     Masahiro Yamada <masahiroy@kernel.org>
Cc:     Miguel Ojeda <ojeda@kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
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Hi Masahiro,

On Mon, Sep 12, 2022 at 5:08 PM Masahiro Yamada <masahiroy@kernel.org> wrote:
>
> I have not figured out where this difference comes from.

It is the `RUSTC_BOOTSTRAP` environment variable: it allows to use
unstable featuers in the stable compiler.

We currently set it in the global `Makefile`, but we could be more
explicit and do it on each command if you think that would be better.

If you want that we keep using the global export, then we can add a
comment explaining this to clarify.

Cheers,
Miguel