diff --git a/src/eval_context.rs b/src/eval_context.rs
index be745a805acc5..e2ed5459d4590 100644
--- a/src/eval_context.rs
+++ b/src/eval_context.rs
@@ -200,9 +200,8 @@ impl<'a, 'tcx> EvalContext<'a, 'tcx> {
             Struct(_)    => unimplemented!(),
             Tuple(_)     => unimplemented!(),
             Function(_)  => unimplemented!(),
-            Array(_, _)  => unimplemented!(),
+            Array(_)  => unimplemented!(),
             Repeat(_, _) => unimplemented!(),
-            Dummy        => unimplemented!(),
         };
 
         Ok(Value::ByVal(primval))
@@ -261,7 +260,7 @@ impl<'a, 'tcx> EvalContext<'a, 'tcx> {
         // TODO(solson): Is this inefficient? Needs investigation.
         let ty = self.monomorphize(ty, substs);
 
-        self.tcx.infer_ctxt(None, None, Reveal::All).enter(|infcx| {
+        self.tcx.infer_ctxt((), Reveal::All).enter(|infcx| {
             ty.layout(&infcx).map_err(EvalError::Layout)
         })
     }
diff --git a/src/terminator/mod.rs b/src/terminator/mod.rs
index cbf9bbda2cf83..c9530f636d2cc 100644
--- a/src/terminator/mod.rs
+++ b/src/terminator/mod.rs
@@ -462,7 +462,7 @@ impl<'a, 'tcx> EvalContext<'a, 'tcx> {
     pub(super) fn fulfill_obligation(&self, trait_ref: ty::PolyTraitRef<'tcx>) -> traits::Vtable<'tcx, ()> {
         // Do the initial selection for the obligation. This yields the shallow result we are
         // looking for -- that is, what specific impl.
-        self.tcx.infer_ctxt(None, None, Reveal::All).enter(|infcx| {
+        self.tcx.infer_ctxt((), Reveal::All).enter(|infcx| {
             let mut selcx = traits::SelectionContext::new(&infcx);
 
             let obligation = traits::Obligation::new(
@@ -833,7 +833,7 @@ pub(super) fn get_impl_method<'a, 'tcx>(
 
     match trait_def.ancestors(impl_def_id).defs(tcx, name, ty::AssociatedKind::Method).next() {
         Some(node_item) => {
-            let substs = tcx.infer_ctxt(None, None, Reveal::All).enter(|infcx| {
+            let substs = tcx.infer_ctxt((), Reveal::All).enter(|infcx| {
                 let substs = substs.rebase_onto(tcx, trait_def_id, impl_substs);
                 let substs = traits::translate_substs(&infcx, impl_def_id,
                                                       substs, node_item.node);
@@ -870,7 +870,7 @@ pub fn find_method<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
 
     match trait_def.ancestors(impl_def_id).defs(tcx, name, ty::AssociatedKind::Method).next() {
         Some(node_item) => {
-            let substs = tcx.infer_ctxt(None, None, Reveal::All).enter(|infcx| {
+            let substs = tcx.infer_ctxt((), Reveal::All).enter(|infcx| {
                 let substs = substs.rebase_onto(tcx, trait_def_id, impl_substs);
                 let substs = traits::translate_substs(&infcx, impl_def_id, substs, node_item.node);
                 tcx.lift(&substs).unwrap_or_else(|| {
diff --git a/src/vtable.rs b/src/vtable.rs
index a2cd2d2729d16..1c589f43175e0 100644
--- a/src/vtable.rs
+++ b/src/vtable.rs
@@ -183,7 +183,7 @@ impl<'a, 'tcx> EvalContext<'a, 'tcx> {
         debug!("normalize_and_test_predicates(predicates={:?})",
                predicates);
 
-        self.tcx.infer_ctxt(None, None, Reveal::All).enter(|infcx| {
+        self.tcx.infer_ctxt((), Reveal::All).enter(|infcx| {
             let mut selcx = SelectionContext::new(&infcx);
             let mut fulfill_cx = traits::FulfillmentContext::new();
             let cause = traits::ObligationCause::dummy();