Message        The linkage register "<registers>" has no effect on
                Alpha and will not be mapped to any register on IA64.
                This condition may cause the SHOWMAPLINKAGE message
                output for this directive to be incorrect.

 Description    The use of an Alpha argument register (R16-R21) in a
                linkage characteristic other than "parameters" or
                "results" has no effect on Alpha.  No mapping to an
                IA64 register will be done for this register.  This
                may cause the mapped linkage shown in the
                showmaplinkage message to be incorrect.

 User Action    Remove the register from the characteristic.