unknown_error     185 ompi/errhandler/errhandler_predefined.c     const char* const unknown_error = "Unknown error";
unknown_error     193 ompi/errhandler/errhandler_predefined.c     const char* usable_err_msg = unknown_error;
unknown_error     223 ompi/errhandler/errhandler_predefined.c     usable_err_msg = (NULL == err_msg) ? unknown_error  : err_msg;