Static rustc_lint_defs::builtin::INEFFECTIVE_UNSTABLE_TRAIT_IMPL

pub static INEFFECTIVE_UNSTABLE_TRAIT_IMPL: &Lint

The ineffective_unstable_trait_impl lint detects #[unstable] attributes which are not used.

Example

#![feature(staged_api)]

#[derive(Clone)]
#[stable(feature = "x", since = "1")]
struct S {}

#[unstable(feature = "y", issue = "none")]
impl Copy for S {}

{{produces}}

Explanation

staged_api does not currently support using a stability attribute on impl blocks. impls are always stable if both the type and trait are stable, and always unstable otherwise.