diff --git a/panda/src/gobj/boundedObject.h b/panda/src/gobj/boundedObject.h
index 584b325b61..72659185a5 100644
--- a/panda/src/gobj/boundedObject.h
+++ b/panda/src/gobj/boundedObject.h
@@ -30,6 +30,7 @@
 #include "pipelineCycler.h"
 #include "typedObject.h"
 #include "pointerTo.h"
+#include "thread.h"
 
 ////////////////////////////////////////////////////////////////////
 //       Class : BoundedObject