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

 Message        System register specified as external register.

 Description    This message is emitted by the code generator used by
                all Compaq compilers for the Alpha architecture.  It
                should never be output when compiling a C program.

 User Action    Please submit a problem report if you encounter this
                message when compiling a C program.