VMS Help CC, Messages, DCLMISMATLNK4  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 Message        <where> "<name>" <modifier>has a type that is not
                allowed because the it has the linkage "<name>".
                Standard linkage will be used.

 Description    Using a special linkage places certain restrictions
                on the type of a function's parameters and return
                value.  In general, the type must be a scalar type
                that can be represented by a register or registers on
                this platform.  In cases where some other type is
                used, the compiler will ignore the special linkage
                and use the standard linkage instead.

 User Action    Either remove the name from the #pragma use_linkage
                directive that specified the special linkage, or
                modify the type to be acceptable to the special
                linkage.