In the attached example, the line 'pp = q' does
not always properly copy the pointer value of 'q' into
'pp'. The error does not show up consistently,
but I found out why by tracking the problem down to
Pointer_ass_item(): on my machine at least (Pentium),
the stgdict of 'pp' has a size == 4 but length == 2.
As a result, the size computed as the quotient is 2,
and then in _CData_set() the memcpy() only copies 2
bytes from the b_ptr of q into the b_ptr of p.