`#[allow(private_bounds)]` does not work when applied directly to the "bad" item.

[TimNN]

I tried this code:

#[allow(private_bounds)]
pub trait Foo: FooImpl {}

trait FooImpl {}

I expected to see this happen: The private_bounds lint is allowed.

Instead, this happened: The private_bounds lint still triggers.

(Applying #[allow(private_bounds)] to the entire module works).

(I'm assuming that this is unintentional, thus reporting as a "bug". If this behavior is intentional, consider this a feature request to change it).

Meta

Latest playground nightly:

1.74.0-nightly (2023-09-01 35e416303e6591a71ef6)

[compiler-errors]

The problem here is that the lint is associated with the private item, not the item which names it in its bounds:

pub trait Foo: FooImpl {}

#[allow(private_bounds)]
trait FooImpl {}

[petrochenkov]

cc @Bryanskiy