Remove unnecessary StructurallyRelateAliases from CombineFields/TypeRelating

Author: compiler-errors

Diff for: compiler/rustc_infer/src/infer/at.rs

@@ -31,7 +31,7 @@ use rustc_middle::ty::{Const, ImplSubject};
 
 use super::*;
 use crate::infer::relate::type_relating::TypeRelating;
-use crate::infer::relate::{Relate, StructurallyRelateAliases, TypeRelation};
+use crate::infer::relate::{Relate, TypeRelation};
 
 /// Whether we should define opaque types or just treat them opaquely.
 ///
@@ -114,7 +114,6 @@ impl<'a, 'tcx> At<'a, 'tcx> {
             ToTrace::to_trace(self.cause, expected, actual),
             self.param_env,
             define_opaque_types,
-            StructurallyRelateAliases::No,
             ty::Contravariant,
         );
         op.relate(expected, actual)?;
@@ -136,7 +135,6 @@ impl<'a, 'tcx> At<'a, 'tcx> {
             ToTrace::to_trace(self.cause, expected, actual),
             self.param_env,
             define_opaque_types,
-            StructurallyRelateAliases::No,
             ty::Covariant,
         );
         op.relate(expected, actual)?;
@@ -177,7 +175,6 @@ impl<'a, 'tcx> At<'a, 'tcx> {
             trace,
             self.param_env,
             define_opaque_types,
-            StructurallyRelateAliases::No,
             ty::Invariant,
         );
         op.relate(expected, actual)?;

Diff for: compiler/rustc_infer/src/infer/relate/type_relating.rs

@@ -21,7 +21,6 @@ pub(crate) struct TypeRelating<'infcx, 'tcx> {
     trace: TypeTrace<'tcx>,
     param_env: ty::ParamEnv<'tcx>,
     define_opaque_types: DefineOpaqueTypes,
-    structurally_relate_aliases: StructurallyRelateAliases,
 
     // Mutable fields.
     ambient_variance: ty::Variance,
@@ -57,15 +56,13 @@ impl<'infcx, 'tcx> TypeRelating<'infcx, 'tcx> {
         trace: TypeTrace<'tcx>,
         param_env: ty::ParamEnv<'tcx>,
         define_opaque_types: DefineOpaqueTypes,
-        structurally_relate_aliases: StructurallyRelateAliases,
         ambient_variance: ty::Variance,
     ) -> TypeRelating<'infcx, 'tcx> {
         TypeRelating {
             infcx,
             trace,
             param_env,
             define_opaque_types,
-            structurally_relate_aliases,
             ambient_variance,
             obligations: vec![],
             cache: Default::default(),
@@ -353,7 +350,7 @@ impl<'tcx> PredicateEmittingRelation<InferCtxt<'tcx>> for TypeRelating<'_, 'tcx>
     }
 
     fn structurally_relate_aliases(&self) -> StructurallyRelateAliases {
-        self.structurally_relate_aliases
+        StructurallyRelateAliases::No
     }
 
     fn register_predicates(