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

 Message        Writable variable resides in nowrt extern model.

 Description    The current extern model places all external objects
                in a read-only section.  An object without a const
                type qualifier in such a section means that while the
                compiler will not diagnose writes to the object, any
                attempt to modify the object at runtime will cause
                the program to fail.  This might not have been what
                you intended.

 User Action    Place non-const objects in sections that can be
                modified.