diff --git a/rust-toolchain b/rust-toolchain
index 39968240..76dc5a3e 100644
--- a/rust-toolchain
+++ b/rust-toolchain
@@ -1 +1 @@
-nightly-2020-06-23
+nightly-2020-07-07
diff --git a/src/mismatch.rs b/src/mismatch.rs
index d712ca37..2488fd80 100644
--- a/src/mismatch.rs
+++ b/src/mismatch.rs
@@ -79,7 +79,7 @@ impl<'a, 'tcx> MismatchRelation<'a, 'tcx> {
             let old_ty = self.tcx.type_of(old_def_id);
             let new_ty = self.tcx.type_of(new_def_id);
             debug!("relating item pair");
-            let _ = self.relate(&old_ty, &new_ty);
+            let _ = self.relate(old_ty, new_ty);
         }
     }
 
@@ -118,13 +118,13 @@ impl<'a, 'tcx> TypeRelation<'tcx> for MismatchRelation<'a, 'tcx> {
     fn relate_with_variance<T: Relate<'tcx>>(
         &mut self,
         _: ty::Variance,
-        a: &T,
-        b: &T,
+        a: T,
+        b: T,
     ) -> RelateResult<'tcx, T> {
         self.relate(a, b)
     }
 
-    fn relate<T: Relate<'tcx>>(&mut self, a: &T, b: &T) -> RelateResult<'tcx, T> {
+    fn relate<T: Relate<'tcx>>(&mut self, a: T, b: T) -> RelateResult<'tcx, T> {
         debug!("relate: mismatch relation: a: {:?}, b: {:?}", a, b);
         Relate::relate(self, a, b)
     }
@@ -166,7 +166,7 @@ impl<'a, 'tcx> TypeRelation<'tcx> for MismatchRelation<'a, 'tcx> {
                         {
                             let b_field_ty = b_field.ty(self.tcx, b_substs);
 
-                            let _ = self.relate(&a_field_ty, &b_field_ty)?;
+                            let _ = self.relate(a_field_ty, b_field_ty)?;
                         }
                     }
 
@@ -193,16 +193,16 @@ impl<'a, 'tcx> TypeRelation<'tcx> for MismatchRelation<'a, 'tcx> {
             }
             (&TyKind::Array(a_t, _), &TyKind::Array(b_t, _))
             | (&TyKind::Slice(a_t), &TyKind::Slice(b_t)) => {
-                let _ = self.relate(&a_t, &b_t)?;
+                let _ = self.relate(a_t, b_t)?;
                 None
             }
             (&TyKind::RawPtr(a_mt), &TyKind::RawPtr(b_mt)) => {
-                let _ = self.relate(&a_mt, &b_mt)?;
+                let _ = self.relate(a_mt, b_mt)?;
                 None
             }
             (&TyKind::Ref(a_r, a_ty, _), &TyKind::Ref(b_r, b_ty, _)) => {
-                let _ = self.relate(&a_r, &b_r)?;
-                let _ = self.relate(&a_ty, &b_ty)?;
+                let _ = self.relate(a_r, b_r)?;
+                let _ = self.relate(a_ty, b_ty)?;
                 None
             }
             (&TyKind::FnDef(a_def_id, a_substs), &TyKind::FnDef(b_def_id, b_substs)) => {
@@ -219,17 +219,17 @@ impl<'a, 'tcx> TypeRelation<'tcx> for MismatchRelation<'a, 'tcx> {
                 Some((a, b))
             }
             (&TyKind::FnPtr(a_fty), &TyKind::FnPtr(b_fty)) => {
-                let _ = self.relate(&a_fty, &b_fty)?;
+                let _ = self.relate(a_fty, b_fty)?;
                 None
             }
             (&TyKind::Dynamic(a_obj, a_r), &TyKind::Dynamic(b_obj, b_r)) => {
-                let _ = self.relate(&a_r, &b_r)?;
+                let _ = self.relate(a_r, b_r)?;
                 let a = a_obj.principal();
                 let b = b_obj.principal();
 
                 if let (Some(a), Some(b)) = (a, b) {
                     if self.check_substs(a.skip_binder().substs, b.skip_binder().substs) {
-                        let _ = self.relate(&a.skip_binder().substs, &b.skip_binder().substs)?;
+                        let _ = self.relate(a.skip_binder().substs, b.skip_binder().substs)?;
                         let a = Res::Def(DefKind::Trait, a.skip_binder().def_id);
                         let b = Res::Def(DefKind::Trait, b.skip_binder().def_id);
                         Some((a, b))
@@ -241,11 +241,11 @@ impl<'a, 'tcx> TypeRelation<'tcx> for MismatchRelation<'a, 'tcx> {
                 }
             }
             (&TyKind::Tuple(as_), &TyKind::Tuple(bs)) => {
-                let _ = as_.iter().zip(bs).map(|(a, b)| self.relate(&a, &b));
+                let _ = as_.iter().zip(bs).map(|(a, b)| self.relate(a, b));
                 None
             }
             (&TyKind::Projection(a_data), &TyKind::Projection(b_data)) => {
-                let _ = self.relate(&a_data, &b_data)?;
+                let _ = self.relate(a_data, b_data)?;
 
                 let a = Res::Def(DefKind::AssocTy, a_data.item_def_id);
                 let b = Res::Def(DefKind::AssocTy, b_data.item_def_id);
@@ -305,8 +305,8 @@ impl<'a, 'tcx> TypeRelation<'tcx> for MismatchRelation<'a, 'tcx> {
 
     fn binders<T: Relate<'tcx>>(
         &mut self,
-        a: &ty::Binder<T>,
-        b: &ty::Binder<T>,
+        a: ty::Binder<T>,
+        b: ty::Binder<T>,
     ) -> RelateResult<'tcx, ty::Binder<T>> {
         Ok(ty::Binder::bind(
             self.relate(a.skip_binder(), b.skip_binder())?,
diff --git a/src/translate.rs b/src/translate.rs
index 70c7fde7..008ff4b0 100644
--- a/src/translate.rs
+++ b/src/translate.rs
@@ -211,7 +211,7 @@ impl<'a, 'tcx> TranslationContext<'a, 'tcx> {
                         let res: Vec<_> = preds
                             .iter()
                             .map(|p| {
-                                match *p.skip_binder() {
+                                match p.skip_binder() {
                                     Trait(existential_trait_ref) => {
                                         let trait_ref = Binder::bind(existential_trait_ref)
                                             .with_self_ty(self.tcx, dummy_self);