Static rustc_lint::unused::UNUSED_ALLOCATION

pub(crate) static UNUSED_ALLOCATION: &'static Lint

The unused_allocation lint detects unnecessary allocations that can be eliminated.

Example

#![feature(box_syntax)]
fn main() {
    let a = (box [1, 2, 3]).len();
}

{{produces}}

Explanation

When a box expression is immediately coerced to a reference, then the allocation is unnecessary, and a reference (using & or &mut) should be used instead to avoid the allocation.