message: never panic middle/dot.rs
diff: @@ -136,8 +136,11 @@ pub fn emit_dot<T: GraphDot>(g: &T) -> String {
  let mut clustermap = HashMap::<T::NodeIndex, Vec<T::NodeIndex>>::new();
  for i in &nodes {
  - let block = g.node_cluster(i);
  - clustermap.entry(T::node_index_new(block.unwrap()))
  + let block = g.node_cluster(i).unwrap_or_else(|| {
  + radeco_err!("Block not found");
  + 0
  + });
  + clustermap.entry(T::node_index_new(block))
  .or_insert_with(Vec::new)
  .push(i.clone());
  }
  