/sys$common/syshlp/helplib.hlb CC, Messages, NOTONEORZERO  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 Message        <Context> the value of "<expression>" is neither 0
                nor 1.

 Description    The __builtin_va_start macro has been used
                incorrectly.

 User Action    Correct the use of the macro.