[Vala] Queue failed to free elements during destruction

[PCMan <pcman tw gmail com>]

Hi list,
Is it by design or it's a bug?
I noticed that data elements of Queue are not freed during destruction of
the queue.
For example:

[Compact]
class Data {
  public string data1;
  public string data2;
}

class Test {
  Test() {
  }

  private Queue<Data?> queue;
}

The generated C code did not free Data in the queue in destructor of Test
class.
With List<Data>, all data are correctly freed.
I'm currently using vala 0.1.4.
Can anyone confirm this or tell me the correct way of using class/struct
with Queue?

Thanks