diff --git a/tests/io_test.cpp b/tests/io_test.cpp
index 6de2cfc..84cb212 100644
--- a/tests/io_test.cpp
+++ b/tests/io_test.cpp
@@ -437,6 +437,4 @@ int main() {
     assert(client_catch);
     io_service->stop();
   }
-
-  return 0;
 }