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

 Message        <Context> an apparent invocation of intrinsic
                function "<name>", <problem>.  It will be treated as
                an ordinary external call.

 Description    A function that could be handled internally by the
                compiler has been called in a manner that is
                inconsistent with expected usage.  In such a case,
                the compiler will generate a run-time call to the
                function.  This could result in performance loss.

 User Action    If the function is intended to refer to the runtime
                library routine, the appropriate header file should
                be included in the source to provide the full
                function prototype and allow certain types of
                argument conversions.  Alternatively, call arguments
                could be type cast as specified in the error message,
                or the function prototype could be added by hand.  If
                the function is not intended to refer to the runtime
                library routine, the intrinsic version can be
                disabled by means of the "#pragma function
                (function_name)" directive.