mariadb/mysql-test/t/query_cache_debug.test

--source include/not_embedded.inc
--source include/have_query_cache.inc
--source include/have_debug.inc

#
# Bug #30887 Server crashes on SET GLOBAL query_cache_size=0
#
flush status;
set query_cache_type=DEMAND;
set global query_cache_size= 1024*1024*512;
--disable_warnings
drop table if exists t1;
--enable_warnings
create table t1 (a varchar(100));
insert into t1 values ('aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa'),('bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb');
connect (bug30887con1, localhost, root, ,test);
connect (bug30887con2, localhost, root, ,test);

connection bug30887con1;
--echo Activate debug hook and attempt to retrieve the statement from the cache.
set session debug='+d,wait_in_query_cache_insert';
--send select SQL_CACHE * from t1;

connection default;
let $wait_condition= select count(*)= 1 from information_schema.processlist where state= 'wait_in_query_cache_insert';
--source include/wait_condition.inc

connection bug30887con2;
--echo On a second connection; clear the query cache.
show status like 'Qcache_queries_in_cache';
set global query_cache_size= 0;

connection default;
--echo Signal the debug hook to release the lock.
select id from information_schema.processlist where state='wait_in_query_cache_insert' into @thread_id;
kill query @thread_id;

--echo Show query cache status.
show status like 'Qcache_queries_in_cache';

disconnect bug30887con1;
disconnect bug30887con2;
set global query_cache_size= 0;
use test;
drop table t1;