crash only happens with the following testcases:

drop table if exists `t1`;
create table `t1` (`a` int)engine=myisam;
insert into `t1` values ();
delete from `t1` order by (@@global.INIT_FILE) asc limit 10;

drop table if exists `t1`;
create table `t1` (`a` int)engine=myisam;
insert into `t1` values ();
delete from `t1` order by (@@global.INNODB_DATA_HOME_DIR) asc limit 10;

drop table if exists `t1`;
create table `t1` (`a` int)engine=myisam;
insert into `t1` values ();
delete from `t1` order by (@@global.INNODB_FLUSH_METHOD) asc limit 10;

drop table if exists `t1`;
create table `t1` (`a` int)engine=myisam;
insert into `t1` values ();
delete from `t1` order by (@@global.RELAY_LOG) asc limit 10;

drop table if exists `t1`;
create table `t1` (`a` int)engine=myisam;
insert into `t1` values ();
delete from `t1` order by (@@global.RELAY_LOG_INDEX) asc limit 10;

drop table if exists `t1`;
create table `t1` (`a` int)engine=myisam;
insert into `t1` values ();
delete from `t1` order by (@@global.REPORT_HOST) asc limit 10;

drop table if exists `t1`;
create table `t1` (`a` int)engine=myisam;
insert into `t1` values ();
delete from `t1` order by (@@global.REPORT_PASSWORD) asc limit 10;

drop table if exists `t1`;
create table `t1` (`a` int)engine=myisam;
insert into `t1` values ();
delete from `t1` order by (@@global.REPORT_USER) asc limit 10;

drop table if exists `t1`;
create table `t1` (`a` int)engine=myisam;
insert into `t1` values ();
delete from `t1` order by (@@global.SECURE_FILE_PRIV) asc limit 10;

drop table if exists `t1`;
create table `t1` (`a` int)engine=myisam;
insert into `t1` values ();
delete from `t1` order by (@@global.SSL_CA) asc limit 10;

drop table if exists `t1`;
create table `t1` (`a` int)engine=myisam;
insert into `t1` values ();
delete from `t1` order by (@@global.SSL_CAPATH) asc limit 10;

drop table if exists `t1`;
create table `t1` (`a` int)engine=myisam;
insert into `t1` values ();
delete from `t1` order by (@@global.SSL_CERT) asc limit 10;

drop table if exists `t1`;
create table `t1` (`a` int)engine=myisam;
insert into `t1` values ();
delete from `t1` order by (@@global.SSL_CIPHER) asc limit 10;

drop table if exists `t1`;
create table `t1` (`a` int)engine=myisam;
insert into `t1` values ();
delete from `t1` order by (@@global.SSL_KEY) asc limit 10;