Lv_arc_rotate_obj_to_angle - does not work in v9.1.0 - potential bug?

I have already posted an issue with the arc example provided In the lvgl v9.1.0 example folder regarding the permissive error which can be fixed by changing

lv_obj_t * label = lv_event_get_user_data(e);


lv_obj_t * label = (lv_obj_t*)lv_event_get_user_data(e);

however the label is not displayed. But when I change

lv_arc_rotate_obj_to_angle(arc, label, lv_arc_get_value(arc))

but when I remove it from the function:

static void value_changed_event_cb(lv_event_t * e)lv_arc_get_value(arc)

and add

lv_obj_align(label, LV_ALIGN_CENTER, 0, -40);

to the lv_example_arc_1 a label is displayed so this suggests that lv_arc_rotate_obj_to_angle has a bug.