Function required_predicates

pub fn required_predicates<'tcx>(
    tcx: TyCtxt<'tcx>,
    def_id: DefId,
    options: BoundsOptions,
) -> GenericPredicates<'tcx>

The predicates that must hold to mention this item. E.g.

// `U: OtherTrait` is required, `Self: Sized` is implied.
trait Trait<U: OtherTrait>: Sized {
    // `T: Clone` is required, `Self::Type<T>: Debug` is implied.
    type Type<T: Clone>: Debug;
}

If add_drop is true, we add a T: Drop bound for every type generic.