fn visit_trait_item(&mut self, _trait_item: &'tcx hir::TraitItem<'tcx>) {}
fn visit_impl_item(&mut self, _impl_item: &'tcx hir::ImplItem<'tcx>) {}
+
+ fn visit_foreign_item(&mut self, _foreign_item: &'tcx hir::ForeignItem<'tcx>) {}
}
fn enforce_impl_params_are_constrained(