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

 Message        An #ifdef or #ifndef is not followed by an
                identifier.

 Description    An #ifdef or #ifndef preprocessing directive was not
                followed by an identifier.  The compiler will
                consider the preprocessor argument to be an
                identifier that is not defined.  Therefore, in these
                cases an #ifdef will always be FALSE, and an #ifndef
                will always be TRUE.

 User Action    Supply a valid identifier to the directive.