Re: [PATCH] rust: cpufreq: clean new `clippy::map_or_identity` lint for Rust 1.98.0

["Alexandre Courbot" <acourbot@nvidia.com>]

On Sat May 30, 2026 at 6:58 PM JST, Miguel Ojeda wrote:
> Starting with Rust 1.98.0 (expected 2026-08-20), Clippy is likely
> introducing a new lint `clippy::map_or_identity` [1][2], which currently
> triggers in a single case:
>
>     warning: expression can be simplified using `Result::unwrap_or()`
>         --> rust/kernel/cpufreq.rs:1326:60
>          |
>     1326 |         PolicyCpu::from_cpu(cpu_id).map_or(0, |mut policy| T::get(&mut policy).map_or(0, |f| f))
>          |                                                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>          |
>          = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#map_or_identity
>          = note: `-W clippy::map-or-identity` implied by `-W clippy::all`
>          = help: to override `-W clippy::all` add `#[allow(clippy::map_or_identity)]`
>     help: consider using `unwrap_or`
>          |
>     1326 -         PolicyCpu::from_cpu(cpu_id).map_or(0, |mut policy| T::get(&mut policy).map_or(0, |f| f))
>     1326 +         PolicyCpu::from_cpu(cpu_id).map_or(0, |mut policy| T::get(&mut policy).unwrap_or(0))
>          |
>
> The suggestion is valid, thus clean it up.
>
> Cc: stable@vger.kernel.org # Needed in 6.12.y and later (Rust is pinned in older LTSs).
> Link: https://github.com/rust-lang/rust-clippy/issues/15801 [1]
> Link: https://github.com/rust-lang/rust-clippy/pull/16052 [2]
> Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>