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From: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Date: Fri, 23 Feb 2024 15:39:47 +0100
Message-ID: <CANiq72ngEZskjH0f=8+cJuQsFTK227bGCxe5G0STMHuPbZYnXg@mail.gmail.com>
Subject: Re: [PATCH v2 2/3] scripts: generate_rust_target: enable building on RISC-V
To: Conor Dooley <conor@kernel.org>
Cc: linux-riscv@lists.infradead.org, Conor Dooley <conor.dooley@microchip.com>, 
	Miguel Ojeda <ojeda@kernel.org>, Alex Gaynor <alex.gaynor@gmail.com>, 
	Wedson Almeida Filho <wedsonaf@gmail.com>, Boqun Feng <boqun.feng@gmail.com>, Gary Guo <gary@garyguo.net>, 
	=?UTF-8?Q?Bj=C3=B6rn_Roy_Baron?= <bjorn3_gh@protonmail.com>, 
	Jonathan Corbet <corbet@lwn.net>, Paul Walmsley <paul.walmsley@sifive.com>, 
	Palmer Dabbelt <palmer@dabbelt.com>, Nathan Chancellor <nathan@kernel.org>, 
	Nick Desaulniers <ndesaulniers@google.com>, Tom Rix <trix@redhat.com>, 
	rust-for-linux@vger.kernel.org, linux-doc@vger.kernel.org, 
	linux-kernel@vger.kernel.org, llvm@lists.linux.dev
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On Fri, Feb 23, 2024 at 2:38=E2=80=AFPM Conor Dooley <conor@kernel.org> wro=
te:
>
> Add the required bits from rust-for-linux to enable generating a RISC-V
> target for rust. The script, written by Miguel, was originally a
> config file contributed by Gary.

Thanks for this Connor!

arm64 is sending these for 6.9:

    https://git.kernel.org/arm64/c/f82811e22b48
    https://git.kernel.org/arm64/c/724a75ac9542

So it would be nice to see if it may be already possible to enable it
via a builtin target + flags instead of the custom target, e.g. arm64
does:

    KBUILD_RUSTFLAGS +=3D --target=3Daarch64-unknown-none -Ctarget-feature=
=3D"-neon"

and so on.

If it does not work, it would be good to know what would be needed for
RISC-V and put it into the unstable features / wanted features list
for Rust.

Either way, it is not a blocker (although you will need a rebase after
arm64 lands to use the `target.json` in the right places).

Cheers,
Miguel