CORBA35 — Forward declaration of value boxes

Summary: It is not clear from the spec whether or not value boxes can be
forward declared, and used recursively. For example,

value v;
struct s

;
value v s;

If value boxes are indeed syntactic sugar, the answer should be yes.
That brings the next question: Does this mean that one can call
create_box_value_tc(), supplying NULL for the original_type, and
then later on fill in the member typecode via fill_in_recursive_tc,
supplying a ValueMemberSeq of length 1?