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

 Message        A comment is neither preceded nor followed by white
                space.

 Description    A comment is neither preceded nor followed by white
                space.  In certain modes the compiler will paste the
                tokens before and after the comment together to form
                a single token.  This behavior is not valid in
                standard C.  Writing programs that rely on this
                behavior might prevent the program from being
                compiled on other platforms.

 User Action    Add white space before or after the comment, or use
                the ## operator to paste tokens together.