diff --git a/src/librustc_mir/interpret/step.rs b/src/librustc_mir/interpret/step.rs
index 6e54420e2eb..1ad8eced3e0 100644
--- a/src/librustc_mir/interpret/step.rs
+++ b/src/librustc_mir/interpret/step.rs
@@ -127,6 +127,9 @@ impl<'a, 'tcx> EvalContext<'a, 'tcx> {
                 self.deallocate_local(old_val)?;
             }
 
+            // Validity checks.  Not yet implemented.
+            Validate(_, _) => {}
+
             // Just a borrowck thing
             EndRegion(..) => {}