diff --git a/scratch/scratch-simulator.cc b/scratch/scratch-simulator.cc
index aa7cc6fa4..1e87bd0ab 100644
--- a/scratch/scratch-simulator.cc
+++ b/scratch/scratch-simulator.cc
@@ -27,4 +27,6 @@ main (int argc, char *argv[])
 
   Simulator::Run ();
   Simulator::Destroy ();
+
+  return 0;
 }