diff --git a/mace/core/net.cc b/mace/core/net.cc
index 22956876262c5b16a042e9e1289e6fd4fc73dca6..a8f1f80e17e2f150ff5b9dda32df3c03e97e8014 100644
--- a/mace/core/net.cc
+++ b/mace/core/net.cc
@@ -37,6 +37,7 @@ bool SimpleNet::Run() {
       return false;
     }
   }
+  return true;
 }
 
 unique_ptr<NetBase> CreateNet(const NetDef& net_def,