[Draft] Server crashes in strdup_root / Query_arena::strdup on SHOW FULL PROCESSLIST

#3  <signal handler called>

#4  strlen () at ../sysdeps/x86_64/strlen.S:106

#5  0x0000561c760f9874 in strdup_root (root=0x7ff07800bf90, str=0x8f8f8f8f8f8f8f8f <error: Cannot access memory at address 0x8f8f8f8f8f8f8f8f>) at /home/travis/src/mysys/my_alloc.c:471

#6  0x0000561c755ffdf7 in Query_arena::strdup (this=0x7ff078006b88, str=0x8f8f8f8f8f8f8f8f <error: Cannot access memory at address 0x8f8f8f8f8f8f8f8f>) at /home/travis/src/sql/sql_class.h:1017

#7  0x0000561c756e417b in mysqld_list_processes (thd=0x7ff078006b70, user=0x0, verbose=true) at /home/travis/src/sql/sql_show.cc:2815

#8  0x0000561c7564d276 in mysql_execute_command (thd=0x7ff078006b70) at /home/travis/src/sql/sql_parse.cc:5050

#9  0x0000561c756563ae in mysql_parse (thd=0x7ff078006b70, rawbuf=0x7ff0780173f8 "SHOW FULL PROCESSLIST", length=21, parser_state=0x7ff07ceda5f0, is_com_multi=false, is_next_command=false) at /home/travis/src/sql/sql_parse.cc:7980

#10 0x0000561c75643ba4 in dispatch_command (command=COM_QUERY, thd=0x7ff078006b70, packet=0x7ff07800e7c1 "", packet_length=21, is_com_multi=false, is_next_command=false) at /home/travis/src/sql/sql_parse.cc:1825

#11 0x0000561c756425f0 in do_command (thd=0x7ff078006b70) at /home/travis/src/sql/sql_parse.cc:1370

#12 0x0000561c757abf7f in do_handle_one_connection (connect=0x561c797c9f10) at /home/travis/src/sql/sql_connect.cc:1402

#13 0x0000561c757abd0c in handle_one_connection (arg=0x561c797c9f10) at /home/travis/src/sql/sql_connect.cc:1308

#14 0x00007ff093e23184 in start_thread (arg=0x7ff07cedb700) at pthread_create.c:312

#15 0x00007ff09333003d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:111

Query (0x7ff0780173f8): SHOW FULL PROCESSLIST

Connection ID (thread ID): 23

Status: NOT_KILLED

Optimizer switch: index_merge=on,index_merge_union=on,index_merge_sort_union=on,index_merge_intersection=on,index_merge_sort_intersection=off,engine_condition_pushdown=off,index_condition_pushdown=on,derived_merge=on,derived_with_keys=on,firstmatch=on,loosescan=on,materialization=on,in_to_exists=on,semijoin=on,partial_match_rowid_merge=on,partial_match_table_scan=on,subquery_cache=on,mrr=off,mrr_cost_based=off,mrr_sort_keys=off,outer_join_with_cache=on,semijoin_with_cache=on,join_cache_incremental=on,join_cache_hashed=on,join_cache_bka=on,optimize_join_buffer_size=off,table_elimination=on,extended_keys=on,exists_to_in=on,orderby_uses_equalities=on,condition_pushdown_for_derived=on,split_materialized=on

perl /home/travis/rqg/runall-new.pl --duration=350 --threads=6 --seed=1519295580 --reporters=Backtrace,ErrorLog,Deadlock --validators=TransformerNoComparator --transformers=ExecuteAsCTE,ExecuteAsDeleteReturning,ExecuteAsExcept,ExecuteAsExecuteImmediate,ExecuteAsInsertSelect,ExecuteAsIntersect,ExecuteAsUnion,ExecuteAsUpdateDelete,ExecuteAsView,ExecuteAsPreparedTwice,ExecuteAsSPTwice --redefine=conf/mariadb/general-workarounds.yy --mysqld=--log_output=FILE --views --vcols --redefine=conf/mariadb/versioning.yy --redefine=conf/mariadb/alter_table.yy --redefine=conf/mariadb/bulk_insert.yy --redefine=conf/mariadb/sequences.yy --redefine=conf/mariadb/xa.yy --basedir=/home/travis/server --mysqld=--log_bin_trust_function_creators=1 --mysqld=--log-bin --mysqld=--max-statement-time=30 --mysqld=--loose-debug_assert_on_not_freed_memory=0 --grammar=conf/runtime/connect_kill_sql.yy --gendata=conf/runtime/connect_kill_data.zz --mysqld=--plugin-load-add=ha_rocksdb --mysqld=--binlog-format=ROW --mysqld=--default-storage-engine=RocksDB --engine=RocksDB --vardir=/home/travis/logs/vardir1_4