diff --git a/lib/cpp/test/TNonblockingServerTest.cpp b/lib/cpp/test/TNonblockingServerTest.cpp
index 434217e..f9aab4c 100644
--- a/lib/cpp/test/TNonblockingServerTest.cpp
+++ b/lib/cpp/test/TNonblockingServerTest.cpp
@@ -83,6 +83,7 @@
     Mutex mutex_;
 
     Runner() {
+      port = 0;
       listenHandler.reset(new ListenEventHandler(&mutex_));
     }