use TraitEngineExt to register obligations

Author: lcnr

compiler/rustc_infer/src/infer/mod.rs

@@ -8,7 +8,7 @@ pub use self::ValuePairs::*;
 use self::opaque_types::OpaqueTypeStorage;
 pub(crate) use self::undo_log::{InferCtxtUndoLogs, Snapshot, UndoLog};
 
-use crate::traits::{self, ObligationCause, PredicateObligations, TraitEngine};
+use crate::traits::{self, ObligationCause, PredicateObligations, TraitEngine, TraitEngineExt};
 
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_data_structures::sync::Lrc;
@@ -618,9 +618,7 @@ impl<'tcx, T> InferOk<'tcx, T> {
         fulfill_cx: &mut dyn TraitEngine<'tcx>,
     ) -> T {
         let InferOk { value, obligations } = self;
-        for obligation in obligations {
-            fulfill_cx.register_predicate_obligation(infcx, obligation);
-        }
+        fulfill_cx.register_predicate_obligations(infcx, obligations);
         value
     }
 }