diff --git a/src/utils.h b/src/utils.h
index fa24947..7c81867 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -412,6 +412,9 @@
   ~ScopedVector() {
     DeleteArray(this->start());
   }
+
+ private:
+  DISALLOW_IMPLICIT_CONSTRUCTORS(ScopedVector);
 };