Merge 10.4 into 10.5

mysql-test/main/cte_recursive.result

@@ -4790,3 +4790,22 @@ a
 NULL
 DROP TABLE t1;
 # End of 10.3 tests
+#
+# MDEV-26108: Recursive CTE embedded into another CTE which is used twice
+#
+create table t1 (a int);
+insert into t1 values (5), (7);
+with cte_e as (
+with recursive cte_r as (
+select a from t1 union select a+1 as a from cte_r r where a < 10
+) select * from cte_r
+) select * from cte_e s1, cte_e s2 where s1.a=s2.a;
+a	a
+5	5
+7	7
+6	6
+8	8
+9	9
+10	10
+drop table t1;
+# End of 10.4 tests