/sys$common/syshlp/helplib.hlb CC, Messages, MAYLOSEDATA2  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 Message        <Context> "<expression>" has a larger data size than
                "<target type>".  Assignment can result in data loss.

 Description    In an assignment of two pointers, the size of the
                source is greater than the size of the destination.
                The assignment can result in a loss of data.  This
                might not have been what you intended.

 User Action    If this was the intended operation, cast the source
                to the type of the destination before the assignment.