message: duplicate function detection bug
diff: @@ -42,7 +42,7 @@ impl BBProgram {
  index_of_main: func_map.get(&"main".to_string()).cloned(),
  func_index,
  };
  - if bb.func_index.len() != num_funcs {
  + if func_map.len() != num_funcs {
  Err(InterpError::DuplicateFunction)
  } else {
  Ok(bb)
  