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Plugin 'MEMORY' has ref_count=1 after shutdown with materialization+semijoin

SET optimizer_switch = 'materialization=on,semijoin=on';

CREATE TABLE t1 (a INT);
INSERT INTO t1 VALUES (8),(9);

CREATE TABLE t2 (b INT);
INSERT INTO t2 VALUES (2),(3);

CREATE TABLE t3 (c INT, INDEX(c));
INSERT INTO t2 VALUES (4),(5);

SELECT * FROM t1 WHERE 9 IN ( SELECT b FROM t2 WHERE 1 IN ( SELECT MIN(c) FROM t3 ) );

In 5.3 and 5.5, it produces the error on shutdown:

140128 19:10:55 [Warning] Plugin 'MEMORY' will be forced to shutdown
140128 19:10:55 [ERROR] Plugin 'MEMORY' has ref_count=1 after shutdown.

In 10.0, it causes assertion failure:

sql/sql_class.cc:1634: virtual THD::~THD(): Assertion `status_var.memory_used == 0' failed.
140128 19:13:28 [ERROR] mysqld got signal 6 ;
#6  0x00007f4e893ea621 in *__GI___assert_fail (assertion=0xfd028f "status_var.memory_used == 0", file=<optimized out>, line=1634, function=0xfd2850 "virtual THD::~THD()") at assert.c:81
#7  0x00000000006295a2 in THD::~THD (this=0x7f4e8333d070, __in_chrg=<optimized out>) at 10.0/sql/sql_class.cc:1634
#8  0x000000000062972a in THD::~THD (this=0x7f4e8333d070, __in_chrg=<optimized out>) at 10.0/sql/sql_class.cc:1639
#9  0x00000000005ab8f2 in unlink_thd (thd=0x7f4e8333d070) at 10.0/sql/mysqld.cc:2715
#10 0x00000000005abc52 in one_thread_per_connection_end (thd=0x7f4e8333d070, put_in_cache=true) at 10.0/sql/mysqld.cc:2826
#11 0x000000000077a563 in do_handle_one_connection (thd_arg=0x7f4e8333d070) at 10.0/sql/sql_connect.cc:1390
#12 0x000000000077a210 in handle_one_connection (arg=0x7f4e8333d070) at 10.0/sql/sql_connect.cc:1293
#13 0x0000000000a9d1f1 in pfs_spawn_thread (arg=0x7f4e83b75df0) at 10.0/storage/perfschema/pfs.cc:1853
#14 0x00007f4e8a94ab50 in start_thread (arg=<optimized out>) at pthread_create.c:304
#15 0x00007f4e89499a7d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112

Stack trace from:

revision-id: psergey@askmonty.org-20140121100700-9g8hl8vx8nmk1e2w
revno: 3965
branch-nick: 10.0

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