private VarSymbol addEnumOrdinalField(JCClassDecl cdef) {
        VarSymbol ordinal = new VarSymbol(PRIVATE|FINAL|SYNTHETIC,
                                          names.fromString("$ordinal"),
                                          syms.intType,
                                          cdef.sym);
        cdef.sym.members().enter(ordinal);
        cdef.defs = cdef.defs.prepend(make.VarDef(ordinal, null));
        return ordinal;
    }