Access to innodb_trx, innodb_locks and innodb_lock_waits along with detached XA's can cause SIGSEGV

diff --git a/storage/innobase/trx/trx0i_s.cc b/storage/innobase/trx/trx0i_s.cc

index 2dc39118d3d..c2cc8c970b0 100644

--- a/storage/innobase/trx/trx0i_s.cc

+++ b/storage/innobase/trx/trx0i_s.cc

@@ -461,6 +461,8 @@ fill_trx_row(

        row->trx_mysql_thread_id = thd_get_thread_id(trx->mysql_thd);

        char    query[TRX_I_S_TRX_QUERY_MAX_LEN + 1];

+       ut_d(if (trx->state == TRX_STATE_PREPARED)

+           DEBUG_SYNC_C("fill_trx_row_before_query_request"));

        if (size_t stmt_len = thd_query_safe(trx->mysql_thd, query,

                                             sizeof query)) {

                row->trx_query = static_cast<const char*>(

diff --git a/storage/innobase/trx/trx0trx.cc b/storage/innobase/trx/trx0trx.cc

index 3b19d213d5a..92bf9de375a 100644

--- a/storage/innobase/trx/trx0trx.cc

+++ b/storage/innobase/trx/trx0trx.cc

@@ -550,6 +550,7 @@ void trx_disconnect_prepared(trx_t *trx)

   trx->read_view.close();

   trx->is_recovered= true;

   trx->mysql_thd= NULL;

+  DEBUG_SYNC_C("trx_disconnect_prepared_reset_thd");

   /* todo/fixme: suggest to do it at innodb prepare */

   trx->will_lock= false;

   trx_sys.rw_trx_hash.put_pins(trx);

--source include/have_innodb.inc                                                

--source include/have_debug.inc                                                 

--source include/have_debug_sync.inc                                            

--source include/count_sessions.inc                                             

--connection default                                                            

create table t (a int) engine=innodb;                                           

insert into t values(1);                                                        

--connect (con_xa, localhost, root,,)                                           

SET DEBUG_SYNC="trx_disconnect_prepared_reset_thd SIGNAL thd_reset";            

xa start '1';                                                                   

insert into t values(1);                                                        

xa end '1';                                                                     

xa prepare '1';                                                                 

--connection default                                                            

SET DEBUG_SYNC="fill_trx_row_before_query_request SIGNAL reached WAIT_FOR fill_row_cont";

--send select * from information_schema.innodb_trx;                             

--connect (con_sync, localhost, root,,)                                         

SET DEBUG_SYNC="now WAIT_FOR reached";                                          

--disconnect con_xa                                                             

SET DEBUG_SYNC="now WAIT_FOR thd_reset";                                        

SET DEBUG_SYNC="now SIGNAL fill_row_cont";                                      

--disconnect con_sync                                                           

--connection default                                                            

--disable_result_log                                                            

# Must crash here with SIGSEGV if not fixed                                     

--reap;                                                                         

--enable_result_log                                                             

xa commit '1';                                                                  

drop table t;                                                                   

SET DEBUG_SYNC="RESET";                                                         

--source include/wait_until_count_sessions.inc