Some cleanup.

sql/handler.cc

@@ -1426,7 +1426,7 @@ int ha_prepare(THD *thd)
       handlerton *ht= ha_info->ht();
       if (ht->prepare)
       {
-        DBUG_EXECUTE_IF("simulate_crash_after_first_engine_prepare",
+        DBUG_EXECUTE_IF("simulate_crash_before_last_engine_prepare",
                         if (!ha_info->next()) DBUG_SUICIDE(););
 
         if (unlikely(prepare_or_error(ht, thd, all)))

sql/log.cc

@@ -11065,6 +11065,10 @@ bool MYSQL_BIN_LOG::recover_explicit_xa_prepare()
                   // partially engine-prepared XA is first cleaned out prior replay
                   thd->lex->sql_command= SQLCOM_XA_ROLLBACK;
                   ha_commit_or_rollback_by_xid(&gev->xid, 0);
+                  if (thd->fix_xid_hash_pins())
+                    sql_print_error(ER(ER_OUT_OF_RESOURCES));
+                  if (auto xs= xid_cache_search(thd, &gev->xid))
+                    xid_cache_delete(thd, xs);
                 }
                 else
                   --recover_xa_count;

sql/xa.cc

@@ -243,7 +243,7 @@ void xid_cache_free()
   Find recovered XA transaction by XID.
 */
 
-static XID_cache_element *xid_cache_search(THD *thd, XID *xid)
+XID_cache_element *xid_cache_search(THD *thd, XID *xid)
 {
   DBUG_ASSERT(thd->xid_hash_pins);
   XID_cache_element *element=
@@ -308,7 +308,7 @@ bool xid_cache_insert(THD *thd, XID_STATE *xid_state, XID *xid)
 }
 
 
-static void xid_cache_delete(THD *thd, XID_cache_element *&element)
+void xid_cache_delete(THD *thd, XID_cache_element *&element)
 {
   DBUG_ASSERT(thd->xid_hash_pins);
   element->mark_uninitialized();

sql/xa.h

@@ -44,6 +44,8 @@ void xid_cache_free(void);
 bool xid_cache_insert(XID *xid);
 bool xid_cache_insert(THD *thd, XID_STATE *xid_state, XID *xid);
 void xid_cache_delete(THD *thd, XID_STATE *xid_state);
+XID_cache_element *xid_cache_search(THD *thd, XID *xid);
+void xid_cache_delete(THD *thd, XID_cache_element *&element);
 
 bool trans_xa_start(THD *thd);
 bool trans_xa_end(THD *thd);