Index: obj_pstk_op.c
===================================================================
--- obj_pstk_op.c	(revision 13053)
+++ obj_pstk_op.c	(revision 13054)
@@ -114,11 +114,13 @@
 	assert(ps->parent_type = PCB_PARENT_DATA);
 
 	if (ctx->clip.restore) {
-		pcb_r_delete_entry(data->padstack_tree, (pcb_box_t *)ps);
+		if (data->padstack_tree != NULL)
+			pcb_r_delete_entry(data->padstack_tree, (pcb_box_t *)ps);
 		pcb_poly_restore_to_poly(data, PCB_TYPE_PSTK, NULL, ps);
 	}
 	if (ctx->clip.clear) {
-		pcb_r_insert_entry(data->padstack_tree, (pcb_box_t *)ps, 0);
+		if (data->padstack_tree != NULL)
+			pcb_r_insert_entry(data->padstack_tree, (pcb_box_t *)ps, 0);
 		pcb_poly_clear_from_poly(data, PCB_TYPE_PSTK, NULL, ps);
 	}