LP:609045 - RQG: close_thread_table(THD*, TABLE**): Assertion `table->key_read == 0' failed with subquery cache

Immediately after executing the following statement with subquery cache enabled:

SELECT COUNT( DISTINCT table2 .`col_int_key` ) , (
SELECT SUBQUERY2_t1 .`col_int_key`
FROM B SUBQUERY2_t1 JOIN CC ON SUBQUERY2_t1 .`col_int_key`
WHERE table1 .`col_varchar_key` ) , table2 .`col_varchar_nokey` field10
FROM D table1 JOIN ( C table2 STRAIGHT_JOIN C table3 ON table2 .`pk` ) ON table3 .`col_varchar_key` = table2 .`col_varchar_key`
GROUP BY field10 ;

the server asserts as follows:

mysqld: sql_base.cc:1380: bool close_thread_table(THD*, TABLE**): Assertion `table->key_read == 0' failed.

#8 0x00897de8 in __assert_fail () from /lib/libc.so.6
#9 0x082dd22f in close_thread_table (thd=0xae6ee90, table_ptr=0xae6eedc) at sql_base.cc:1380
#10 0x082dcd7b in close_open_tables (thd=0xae6ee90) at sql_base.cc:1203
#11 0x082dd0db in close_thread_tables (thd=0xae6ee90) at sql_base.cc:1355
#12 0x0828fb23 in dispatch_command (command=COM_QUERY, thd=0xae6ee90, packet=0xae87271 "", packet_length=379) at sql_parse.cc:1613
#13 0x0828dea8 in do_command (thd=0xae6ee90) at sql_parse.cc:890
#14 0x0828b008 in handle_one_connection (arg=0xae6ee90) at sql_connect.cc:1153
#15 0x00a08919 in start_thread () from /lib/libpthread.so.0
#16 0x00951e5e in clone () from /lib/libc.so.6