This issue will track the approval and stabilization of the attribute coverage, needed to give developers a way to "hide" a function from the coverage instrumentation enabled by rustc -Z instrument-coverage.

The Eq trait in the std library implements a marker function that is not meant to be executed, but results in an uncovered region in all rust programs that derive Eq. This attribute will allow the compiler to skip that function, and remove the uncovered regions.

Unresolved questions

• is it ok that the attribute applied to the crate root, a function, or a module applies to all items within the marked item? So far we do not have such attributes other than the lint level attributes.