Re: [PATCH 2/3] rust: clippy: disable `addr_of!` and `addr_of_mut` macros

[Benno Lossin]

On Thu Mar 13, 2025 at 6:33 AM CET, Antonio Hickey wrote:
> With the `raw_ref_op` feature enabled we no longer want to
> allow use of `addr_of!` and `addr_of_mut!` macros.
>
> We instead want to use `&raw` and `&raw mut` to get raw
> pointers to a place.
>
> Suggested-by: Benno Lossin <y86-dev@xxxxxxxxxxxxxx>
> Link: https://github.com/Rust-for-Linux/linux/issues/1148
> Signed-off-by: Antonio Hickey <contact@xxxxxxxxxxxxxxxxx>

This patch needs to be done after changing all occurrences of
`addr_of[_mut]!`, ie the next one (otherwise it would warn about them).

I also noticed that this feature sadly doesn't work very well, see

    https://rust-for-linux.zulipchat.com/#narrow/channel/291565-Help/topic/.2Eclippy.2Etoml.20has.20no.20effect

and

    https://github.com/rust-lang/rust-clippy/issues/11431

---
Cheers,
Benno

> ---
>  .clippy.toml | 4 ++++
>  1 file changed, 4 insertions(+)
>
> diff --git a/.clippy.toml b/.clippy.toml
> index 815c94732ed7..95c73959f039 100644
> --- a/.clippy.toml
> +++ b/.clippy.toml
> @@ -8,4 +8,8 @@ disallowed-macros = [
>      # The `clippy::dbg_macro` lint only works with `std::dbg!`, thus we simulate
>      # it here, see: https://github.com/rust-lang/rust-clippy/issues/11303.
>      { path = "kernel::dbg", reason = "the `dbg!` macro is intended as a debugging tool" },
> +    # With `raw_ref_op` feature enabled we no longer want to allow use of `addr_of!`
> +    # and `addr_of_mut!` macros, but instead use `&raw` or `&raw mut`.
> +    { path = "core::ptr::addr_of_mut", reason = "use `&raw mut` instead `addr_of_mut!`" },
> +    { path = "core::ptr::addr_of", reason = "use `&raw` instead `addr_of!`" },
>  ]