RS.CLIPPY.NON_CANONICAL_CLONE_IMPL

Non-canonical implementation of `Clone` on a `Copy` type

This checker is a Clippy lint created by The Rust Project Contributors. The documentation shown here is a copy of the original documentation for: non_canonical_clone_impl. Copyright ©2025 The Rust Team. All rights reserved.

What it does

Checks for non-canonical implementations of Clone when Copy is already implemented.

Why is this bad?

If both Clone and Copy are implemented, they must agree. This can done by dereferencing self in Clone's implementation, which will avoid any possibility of the implementations becoming out of sync.

Example

#[derive(Eq, PartialEq)]
struct A(u32);

impl Clone for A {
    fn clone(&self) -> Self {
        Self(self.0)
    }
}

impl Copy for A {}

Use instead:

#[derive(Eq, PartialEq)]
struct A(u32);

impl Clone for A {
    fn clone(&self) -> Self {
        *self
    }
}

impl Copy for A {}

Past names

incorrect_clone_impl_on_copy_type