Unused variable warning for default trait methods

[CryZe]

Given the following code: Playground

pub trait AutoSplitter {
    type Data;
    fn update(&mut self) -> Option<Self::Data>;
    fn should_start(data: &Self::Data) -> bool {
        false
    }
}

The current output is:

warning: unused variable: `data`
 --> src/lib.rs:4:21
  |
4 |     fn should_start(data: &Self::Data) -> bool {
  |                     ^^^^ help: if this is intentional, prefix it with an underscore: `_data`
  |
  = note: `#[warn(unused_variables)]` on by default

Ideally the compiler should not emit any warnings as prefixing the parameter with an underscore would negatively affect the documentation and auto generated implementations via an IDE / rust-analyzer.

[ehuss]

I believe this is a duplicate of #64723, #26487, and #14027. Per #26487 (comment), it sounds like the lang team would prefer to not make this change.

[ehuss]

Closing as a duplicate of the above linked issues.