Hello,

I'm having trouble passing around a pointer between interpreted Squeak
code and compiled plugin code.  I have a primitive method that returns
a pointer like this:

^ aPtr asOop: Unsigned

This seems to work fine; depending on the value, I get either a
SmallInteger or a LargePositiveInteger.  The problem arises when I try
to pass this into another primitive method that looks like this:

primNeedPointer: aPtr

    self 
        primitive: 'primNeedPointer'
	parameters: #(Unsigned)
    "more stuff..."

The generated C code causing the failure is:

interpreterProxy->success(interpreterProxy->isKindOf(interpreterProxy->stackValue(0), "Unsigned"));

Looking at the code for isKindOf(), it is clear why it fails: the
object (a SmallInteger or LargePositiveInteger) is not an instance
of Unsigned or one of its subclasses.

I followed the directions on:
http://minnow.cc.gatech.edu/squeak/850
as closely as possible.  What am I doing wrong?

Thanks,
Joshua