NOEQUALITY

Message        <Context> "<expression1>" and "<expression2>" cannot
               be compared for equality or inequality.

Description    Because of their types, the two expressions cannot be
               compared for equality or inequality.  The rules for
               which types can be compared are rather complicated
               and differ based upon the compiler mode.  Refer to
               the language documentation for a complete list of
               valid combinations.

User Action    Modify the comparison to use valid types.  This can
               often be done by casting one of the expressions to
               the type of the other.