diff --git a/panda/src/net/connection.cxx b/panda/src/net/connection.cxx
index 180bd08ad0..3fed60396f 100644
--- a/panda/src/net/connection.cxx
+++ b/panda/src/net/connection.cxx
@@ -470,7 +470,7 @@ do_flush() {
   Socket_TCP *tcp;
   DCAST_INTO_R(tcp, _socket, false);
 
-  bool okflag = (tcp->SendData(_queued_data) == _queued_data.size());
+  bool okflag = (tcp->SendData(_queued_data) == (int)_queued_data.size());
 
   _queued_data = string();
   _queued_count = 0;