Cannot debug nestest struct with CDB when python dumpers enabled

typedef struct {
  union {
    struct {
      int bit0: 1;
      int rest: 7;
    } bit;
    int byte;
  } bar;
} Foo;

int main()
{
  Foo foo;	
  foo.bar.byte = 42;
  foo.bar.bit.bit0 = 1;	
  return 0; // break here: foo not accessible
} // step here: foo accessible, but bit not