CPP13 — Valuetypes as operation arguments

Summary: The C++ mapping document (98-09-03, p. 108) states that "... the callee
shall receive a copy of each valuetype argument passed to it even if the
caller and callee are collocated in the same process."

In the collocated case, should the ORB invoke _copy_value() to produce
the copy?

Since the user could implement _copy_value() to return a nil value, it
seems unlikely that the ORB could rely on this mechanism. However, a
properly implemented _copy_value() would likely provide a significant
speed improvement over marshalling and unmarshalling.