diff --git a/mysql-test/r/errors.result b/mysql-test/r/errors.result
index 23c77d3978c..bf75bf73862 100644
--- a/mysql-test/r/errors.result
+++ b/mysql-test/r/errors.result
@@ -168,3 +168,7 @@ UPDATE t1 SET a = 'new'
 WHERE COLUMN_CREATE( 1, 'v', 1, 'w' ) IS NULL;
 ERROR 22007: Illegal value used as argument of dynamic column function
 drop table t1;
+set max_session_mem_used = 8192;
+select * from seq_1_to_1000;
+ERROR HY000: Engine SEQUENCE failed to discover table `test`.`seq_1_to_1000` with 'create table seq (seq bigint unsigned primary key)'
+set global max_session_mem_used = default;
diff --git a/mysql-test/t/errors.test b/mysql-test/t/errors.test
index 6ce6e439919..9d5cbef89b1 100644
--- a/mysql-test/t/errors.test
+++ b/mysql-test/t/errors.test
@@ -1,6 +1,7 @@
 #
 # Test some error conditions
 #
+--source include/have_sequence.inc
 
 --disable_warnings
 drop table if exists t1;
@@ -198,3 +199,11 @@ CREATE TABLE t1 (a CHAR(3), b BLOB);
 UPDATE t1 SET a = 'new'
 WHERE COLUMN_CREATE( 1, 'v', 1, 'w' ) IS NULL;
 drop table t1;
+
+#
+# errors caused by max_session_mem_used
+#
+set max_session_mem_used = 8192;
+--error ER_SQL_DISCOVER_ERROR
+select * from seq_1_to_1000;
+set global max_session_mem_used = default;
diff --git a/sql/handler.cc b/sql/handler.cc
index aa87da5dd44..dae47668410 100644
--- a/sql/handler.cc
+++ b/sql/handler.cc
@@ -4857,7 +4857,12 @@ static my_bool discover_handlerton(THD *thd, plugin_ref plugin,
     {
       if (error)
       {
-        DBUG_ASSERT(share->error); // tdc_lock_share needs that
+        if (!share->error)
+        {
+          share->error= OPEN_FRM_ERROR_ALREADY_ISSUED;
+          plugin_unlock(0, share->db_plugin);
+        }
+
         /*
           report an error, unless it is "generic" and a more
           specific one was already reported
diff --git a/sql/mysqld.cc b/sql/mysqld.cc
index 1e6ee4decbe..17172207613 100644
--- a/sql/mysqld.cc
+++ b/sql/mysqld.cc
@@ -3939,8 +3939,9 @@ static void my_malloc_size_cb_func(long long size, my_bool is_thread_specific)
                         (longlong) thd->status_var.local_memory_used,
                         size));
     thd->status_var.local_memory_used+= size;
-    if (thd->status_var.local_memory_used > (int64)thd->variables.max_mem_used &&
-        !thd->killed)
+    if (size > 0 &&
+        thd->status_var.local_memory_used > (int64)thd->variables.max_mem_used &&
+        !thd->killed && !thd->get_stmt_da()->is_set())
     {
       char buf[1024];
       thd->killed= KILL_QUERY;
@@ -6646,11 +6647,12 @@ void handle_connections_sockets()
     */
 
     DBUG_PRINT("info", ("Creating THD for new connection"));
-    if (!(thd= new THD))
+    if (!(thd= new THD) || thd->is_error())
     {
       (void) mysql_socket_shutdown(new_sock, SHUT_RDWR);
       (void) mysql_socket_close(new_sock);
       statistic_increment(connection_errors_internal, &LOCK_status);
+      delete thd;
       continue;
     }
     /* Set to get io buffers to be part of THD */
diff --git a/sql/sql_class.cc b/sql/sql_class.cc
index 304036a67ff..6fb74d6e14c 100644
--- a/sql/sql_class.cc
+++ b/sql/sql_class.cc
@@ -879,6 +879,7 @@ THD::THD(bool is_wsrep_applier)
    debug_sync_control(0),
 #endif /* defined(ENABLED_DEBUG_SYNC) */
    wait_for_commit_ptr(0),
+   m_internal_handler(0),
    main_da(0, false, false),
    m_stmt_da(&main_da),
    tdc_hash_pins(0),
@@ -1073,7 +1074,6 @@ THD::THD(bool is_wsrep_applier)
                                               MYF(MY_WME|MY_THREAD_SPECIFIC));
   }
 
-  m_internal_handler= NULL;
   m_binlog_invoker= INVOKER_NONE;
   memset(&invoker_user, 0, sizeof(invoker_user));
   memset(&invoker_host, 0, sizeof(invoker_host));