[#MDEV-8224] Server crashes in get_server_from_table_to

The problem exists in MySQL 5.5, but not in 5.6/5.7, I assume it was fixed at some point.

create server '' foreign data wrapper w2 options (host '127.0.0.1');

--exec echo "wait" > $MYSQLTEST_VARDIR/tmp/mysqld.1.expect

--shutdown_server 10

--source include/wait_until_disconnected.inc

--exec echo "restart" > $MYSQLTEST_VARDIR/tmp/mysqld.1.expect

Stack trace from 5.5 commit 0014bdc7ee
#3 <signal handler called>
#4 __strlen_sse2 () at ../sysdeps/x86_64/multiarch/../strlen.S:32
#5 0x000000000072daf9 in get_server_from_table_to_cache (table=0x7fb48ed4c460) at 5.5/sql/sql_servers.cc:330
#6 0x000000000072d7f7 in servers_load (thd=0x7fb491b49060, tables=0x7ffd8236d300) at 5.5/sql/sql_servers.cc:220
#7 0x000000000072d9ab in servers_reload (thd=0x7fb491b49060) at 5.5/sql/sql_servers.cc:275
#8 0x000000000072d6b0 in servers_init (dont_read_servers_table=false) at 5.5/sql/sql_servers.cc:178
#9 0x000000000058c53f in mysqld_main (argc=84, argv=0x7fb492813bb0) at 5.5/sql/mysqld.cc:4986
#10 0x000000000058421c in main (argc=6, argv=0x7ffd8236dac8) at 5.5/sql/main.cc:25

[MDEV-8224] Server crashes in get_server_from_table_to_cache on empty name Created: 2015-05-25 Updated: 2015-06-03 Resolved: 2015-06-03
Status:	Closed
Project:	MariaDB Server
Component/s:	Admin statements
Affects Version/s:	5.5, 10.0, 10.1
Fix Version/s:	5.5.44, 10.0.20