MDEV-14185 CREATE TEMPORARY TABLE AS SELECT causes error 1290 with read_only and InnoDB.

handler::ha_create_handler_files shouldn't call the
mark_trx_read_write() for the temporary table.

mysql-test/r/read_only_innodb.result

@@ -221,6 +221,14 @@ a	a
 5	10
 DROP TABLE temp1, temp2;
 
+# MDEV-14185 CREATE TEMPORARY TABLE AS SELECT causes error 1290 with read_only and InnoDB.
+
+CREATE TEMPORARY TABLE temp1 ENGINE=INNODB AS SELECT a FROM t1;
+SELECT * FROM temp1;
+a
+1
+DROP TABLE temp1;
+
 # Disconnect and cleanup
 
 SET GLOBAL READ_ONLY = OFF;

mysql-test/t/read_only_innodb.test

@@ -243,6 +243,15 @@ UPDATE temp1,temp2 SET temp1.a = 5, temp2.a = 10;
 SELECT * FROM temp1, temp2;
 DROP TABLE temp1, temp2;
 
+--echo
+--echo # MDEV-14185 CREATE TEMPORARY TABLE AS SELECT causes error 1290 with read_only and InnoDB.
+--echo
+
+CREATE TEMPORARY TABLE temp1 ENGINE=INNODB AS SELECT a FROM t1;
+SELECT * FROM temp1;
+DROP TABLE temp1;
+
+
 --echo
 --echo # Disconnect and cleanup
 --echo

sql/handler.cc

@@ -3770,7 +3770,8 @@ int
 handler::ha_create_handler_files(const char *name, const char *old_name,
                         int action_flag, HA_CREATE_INFO *info)
 {
-  mark_trx_read_write();
+  if (!info || !(info->options & HA_LEX_CREATE_TMP_TABLE))
+    mark_trx_read_write();
 
   return create_handler_files(name, old_name, action_flag, info);
 }