diff --git a/panda/src/pgraph/renderState.cxx b/panda/src/pgraph/renderState.cxx
index 21a72d398f..f85e961f3b 100644
--- a/panda/src/pgraph/renderState.cxx
+++ b/panda/src/pgraph/renderState.cxx
@@ -692,6 +692,7 @@ clear_cache() {
       if (state->_self_compose != (RenderState *)NULL && 
           state->_self_compose != state) {
         unref_delete((RenderState *)state->_self_compose);
+        state->_self_compose = (RenderState *)NULL;
       }
     }
 
diff --git a/panda/src/pgraph/transformState.cxx b/panda/src/pgraph/transformState.cxx
index fce4db953b..44c1eb6b74 100644
--- a/panda/src/pgraph/transformState.cxx
+++ b/panda/src/pgraph/transformState.cxx
@@ -723,6 +723,7 @@ clear_cache() {
       if (state->_self_compose != (TransformState *)NULL && 
           state->_self_compose != state) {
         unref_delete((TransformState *)state->_self_compose);
+        state->_self_compose = (TransformState *)NULL;
       }
     }