Use `retain` for `waiting_cache` in `apply_rewrites()`.
It's more concise, more idiomatic, and measurably faster.
diff --git a/src/librustc_data_structures/obligation_forest/mod.rs b/src/librustc_data_structures/obligation_forest/mod.rs
index 0fa1f70..5b95bb1 100644
--- a/src/librustc_data_structures/obligation_forest/mod.rs
+++ b/src/librustc_data_structures/obligation_forest/mod.rs
@@ -717,17 +717,15 @@
// This updating of `self.waiting_cache` is necessary because the
// removal of nodes within `compress` can fail. See above.
- let mut kill_list = vec![];
- for (predicate, index) in &mut self.waiting_cache {
+ self.waiting_cache.retain(|_predicate, index| {
let new_i = node_rewrites[index.index()];
if new_i >= nodes_len {
- kill_list.push(predicate.clone());
+ false
} else {
*index = NodeIndex::new(new_i);
+ true
}
- }
-
- for predicate in kill_list { self.waiting_cache.remove(&predicate); }
+ });
}
}
