EMPTYCHARCONST

Message        Empty character constant.

Description    In some modes the HP C compiler will allow a null
               character constant.  The compiler will give this
               constant a value of zero.  Accepting an empty
               character constant is a language extension.  Empty
               character constants are not valid in standard C.
               Writing programs that rely on this behavior might
               prevent the program from being compiled on other
               platforms.

User Action    Replace the empty character constant with '\0'.