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From: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Date: Tue, 6 Jul 2021 20:36:43 +0200
Message-ID: <CANiq72no33T6RXMyZ18bS_nVaUcOpWEmu15Bs=+zJPnnhrnYRA@mail.gmail.com>
Subject: Re: [TECH TOPIC] Rust for Linux
To: Linus Walleij <linus.walleij@linaro.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>, Leon Romanovsky <leon@kernel.org>, ksummit@lists.linux.dev
Content-Type: text/plain; charset="UTF-8"

On Tue, Jul 6, 2021 at 8:00 PM Linus Walleij <linus.walleij@linaro.org> wrote:
>
> I brought this up for discussion with Miguel et al and it turns out
> the project to develop a GCC front-end for Rust is now well under
> way and there is already a frankencompiler using LLVM first
> and then feeding that into GCC IIUC.

By the latter, I think you are referring to `rustc_codegen_gcc` -- in
that case, a quick note: it does not involve LLVM. `rustc` has its own
set of IRs which then gets translated into LLVM IR (in the most common
backend), but in the case of `rustc_codegen_gcc` it gets translated
into something libgccjit can consume. There is also a third backend in
the works, called cranelift, for different use cases.

So `rustc_codegen_gcc` is basically a very quick way of supporting the
entirety of the Rust language (exactly as `rustc` supports it) but
having a GCC codegen path.

Cheers,
Miguel