message: mark some unused variables
diff: use crate::{
  cycle::CycleRecoveryStrategy,
  - ingredient::{Ingredient, MutIngredient},
  + ingredient::Ingredient,
  key::{DatabaseKeyIndex, DependencyIndex},
  runtime::{local_state::QueryInputs, Runtime},
  AsId, IngredientIndex, Revision,
  @@ -37,7 +37,7 @@ where
  }
  }
  - pub fn new_input(&mut self, runtime: &mut Runtime) -> Id {
  + pub fn new_input(&mut self, _runtime: &mut Runtime) -> Id {
  let next_id = self.counter;
  self.counter += 1;
  Id::from_id(crate::Id::from(next_id))
  @@ -48,7 +48,7 @@ impl<DB: ?Sized, Id> Ingredient<DB> for InputIngredient<Id>
  where
  Id: InputId,
  {
  - fn maybe_changed_after(&self, db: &DB, input: DependencyIndex, revision: Revision) -> bool {
  + fn maybe_changed_after(&self, _db: &DB, _input: DependencyIndex, _revision: Revision) -> bool {
  // Input ingredients are just a counter, they store no data, they are immortal.
  // Their *fields* are stored in function ingredients elsewhere.
  false
  