The following query:
SELECT * FROM t2 WHERE a = SOME (
SELECT a FROM v1 WHERE v1.c = t2.c
);

returns a no rows on its second execution as a prepared statement with semijoin.

explain:

id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t2 ALL NULL NULL NULL NULL 1 Using where; Start temporary
1 PRIMARY t1 ALL NULL NULL NULL NULL 1 Using where; End temporary; Using join buffer (flat, BNL join)

correct result:

EXECUTE st1;
a b c
1 r r

minimal optimizer switch: semijoin=on;
full optimizer switch: index_merge=on,index_merge_union=on,index_merge_sort_union=on,index_merge_intersection=on,index_merge_sort_intersection=off,index_condition_pushdown=off,derived_merge=off,derived_with_keys=off,firstmatch=off,loosescan=off,materialization=off,in_to_exists=on,semijoin=on,partial_match_rowid_merge=on,partial_match_table_scan=on,subquery_cache=off,mrr=off,mrr_cost_based=off,mrr_sort_keys=off,outer_join_with_cache=off,semijoin_with_cache=off,join_cache_incremental=on,join_cache_hashed=on,join_cache_bka=on,optimize_join_buffer_size=off,table_elimination=on

bzr version-info
revision-id: <email address hidden>
date: 2011-09-10 18:01:27 +0300
build-date: 2011-09-14 10:54:25 +0300
revno: 3183
branch-nick: maria-5.3

test case:

--source include/have_innodb.inc
SET SESSION optimizer_switch='semijoin=on';

CREATE TABLE t1 ( c varchar(1)) engine=innodb;
INSERT INTO t1 VALUES ('r');

CREATE TABLE t2 ( a integer, b varchar(1), c varchar(1)) engine=innodb;
INSERT INTO t2 VALUES (1,'r','r');

CREATE OR REPLACE VIEW v1 AS SELECT * FROM t1;

PREPARE st1 FROM '
SELECT * FROM t2 WHERE a = SOME (
SELECT a FROM v1 WHERE v1.c = t2.c
)
';
EXECUTE st1;
EXECUTE st1;