Get rid of `ToPolyTraitRef`

2 files changed, 7 insertions, 5 deletions

diff --git a/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs b/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs
index 968dc631e50..b370f802052 100644
--- a/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs
+++ b/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs
@@ -16,7 +16,7 @@ use rustc_infer::traits::{
     Obligation, ObligationCause, PolyTraitObligation, PredicateObligations, SelectionError,
 };
 use rustc_middle::ty::fast_reject::DeepRejectCtxt;
-use rustc_middle::ty::{self, ToPolyTraitRef, Ty, TypeVisitableExt, TypingMode};
+use rustc_middle::ty::{self, Ty, TypeVisitableExt, TypingMode};
 use rustc_middle::{bug, span_bug};
 use rustc_type_ir::Interner;
 use tracing::{debug, instrument, trace};
@@ -186,10 +186,11 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
                     }
 
                     selcx.infcx.probe(|_| {
+                        // We checked the polarity already
                         match selcx.match_normalize_trait_ref(
                             obligation,
                             placeholder_trait_predicate.trait_ref,
-                            bound.to_poly_trait_ref(),
+                            bound.map_bound(|pred| pred.trait_ref),
                         ) {
                             Ok(None) => {
                                 candidates.vec.push(ProjectionCandidate(idx));
diff --git a/compiler/rustc_trait_selection/src/traits/select/confirmation.rs b/compiler/rustc_trait_selection/src/traits/select/confirmation.rs
index 0ccb0fc0615..729ae3f2c2a 100644
--- a/compiler/rustc_trait_selection/src/traits/select/confirmation.rs
+++ b/compiler/rustc_trait_selection/src/traits/select/confirmation.rs
@@ -16,7 +16,7 @@ use rustc_hir::lang_items::LangItem;
 use rustc_infer::infer::{DefineOpaqueTypes, HigherRankedType, InferOk};
 use rustc_infer::traits::ObligationCauseCode;
 use rustc_middle::traits::{BuiltinImplSource, SignatureMismatchData};
-use rustc_middle::ty::{self, GenericArgsRef, ToPolyTraitRef, Ty, TyCtxt, Upcast};
+use rustc_middle::ty::{self, GenericArgsRef, Ty, TyCtxt, Upcast};
 use rustc_middle::{bug, span_bug};
 use rustc_span::def_id::DefId;
 use rustc_type_ir::elaborate;
@@ -458,8 +458,9 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
         ensure_sufficient_stack(|| {
             let cause = obligation.derived_cause(ObligationCauseCode::BuiltinDerived);
 
-            let poly_trait_ref = obligation.predicate.to_poly_trait_ref();
-            let trait_ref = self.infcx.enter_forall_and_leak_universe(poly_trait_ref);
+            assert_eq!(obligation.predicate.polarity(), ty::PredicatePolarity::Positive);
+            let trait_ref =
+                self.infcx.enter_forall_and_leak_universe(obligation.predicate).trait_ref;
             let trait_obligations = self.impl_or_trait_obligations(
                 &cause,
                 obligation.recursion_depth + 1,