Fixed build with newest nightly.

Author: ibabushkin

src/mapping.rs

@@ -323,13 +323,13 @@ impl NameMapping {
                 Enum |
                 Variant |
                 Trait |
-                Existential |
                 TyAlias |
                 ForeignTy |
                 TraitAlias | // TODO: will need some handling later on
                 AssocTy |
-                AssocExistential |
-                TyParam => Some(&mut self.type_map),
+                TyParam |
+                OpaqueTy |
+                AssocOpaqueTy => Some(&mut self.type_map),
                 Fn |
                 Const |
                 ConstParam |

src/mismatch.rs

@@ -12,6 +12,7 @@ use rustc::{
         self,
         relate::{Relate, RelateResult, TypeRelation},
         subst::SubstsRef,
+        ParamEnv,
         Ty, TyCtxt,
         Visibility::Public,
     },
@@ -105,6 +106,10 @@ impl<'a, 'tcx> TypeRelation<'tcx> for MismatchRelation<'a, 'tcx> {
         self.tcx
     }
 
+    fn param_env(&self) -> ParamEnv<'tcx> {
+        ParamEnv::empty()
+    }
+
     fn tag(&self) -> &'static str {
         "Mismatch"
     }

src/traverse.rs

@@ -239,9 +239,7 @@ fn diff_structure<'tcx>(
                             | (Macro(_), Macro(_))
                             | (TraitAlias, TraitAlias)
                             | (ForeignTy, ForeignTy)
-                            | (ConstParam, ConstParam)
-                            | (AssocExistential, AssocExistential)
-                            | (Existential, Existential) => {}
+                            | (ConstParam, ConstParam) => {}
                             // statics are subject to mutability comparison
                             (Static, Static) => {
                                 let old_mut = tcx.is_mutable_static(o_def_id);