Drive-by comment fixes

Co-Authored-By: Gabriel Smith <yodaldevoid@users.noreply.github.com>

Author: varkor

src/librustc/infer/type_variable.rs

@@ -17,7 +17,7 @@ pub struct TypeVariableTable<'tcx> {
     /// the known value.
     eq_relations: ut::UnificationTable<ut::InPlace<TyVidEqKey<'tcx>>>,
 
-    /// Two variables are unified in `eq_relations` when we have a
+    /// Two variables are unified in `sub_relations` when we have a
     /// constraint `?X <: ?Y` *or* a constraint `?Y <: ?X`. This second
     /// table exists only to help with the occurs check. In particular,
     /// we want to report constraints like these as an occurs check
@@ -365,7 +365,7 @@ impl sv::SnapshotVecDelegate for Delegate {
 
     fn reverse(_values: &mut Vec<TypeVariableData>, _action: Instantiate) {
         // We don't actually have to *do* anything to reverse an
-        // instanation; the value for a variable is stored in the
+        // instantiation; the value for a variable is stored in the
         // `eq_relations` and hence its rollback code will handle
         // it. In fact, we could *almost* just remove the
         // `SnapshotVec` entirely, except that we would have to

src/librustc/infer/unify_key.rs

@@ -12,8 +12,7 @@ impl UnifyKey for ty::IntVid {
     fn tag() -> &'static str { "IntVid" }
 }
 
-impl EqUnifyValue for IntVarValue {
-}
+impl EqUnifyValue for IntVarValue {}
 
 #[derive(PartialEq, Copy, Clone, Debug)]
 pub struct RegionVidKey {
@@ -62,8 +61,7 @@ impl UnifyKey for ty::FloatVid {
     fn tag() -> &'static str { "FloatVid" }
 }
 
-impl EqUnifyValue for FloatVarValue {
-}
+impl EqUnifyValue for FloatVarValue {}
 
 impl ToType for FloatVarValue {
     fn to_type<'a, 'gcx, 'tcx>(&self, tcx: TyCtxt<'a, 'gcx, 'tcx>) -> Ty<'tcx> {