MDEV-13180 Unused left join causes server crash

already fixed by be55bbc2
just add a test case

mysql-test/r/group_by.result

@@ -2545,6 +2545,14 @@ select
 from t4;
 ERROR 42S22: Reference 'field7' not supported (reference to group function)
 drop table t1, t2, t3, t4;
+create table t1 (i1 int);
+insert into t1 values (1);
+create table t2 (i int);
+insert into t2 values (2);
+select 1 from t1 left join t2 b on b.i = (select max(b.i) from t2);
+1
+1
+drop table t1, t2;
 create table t1 (c1 int, c2 int);
 create table t2 (c1 int, c2 int);
 select t1.c1 as c1, t2.c2 as c1 from t1, t2 where t1.c1 < 20 and t2.c2 > 5 group by t1.c1, t2.c2 having t1.c1 < 3;

mysql-test/t/group_by.test

@@ -1722,6 +1722,17 @@ select
 from t4;
 drop table t1, t2, t3, t4;
 
+#
+# MDEV-13180 Unused left join causes server crash
+#
+create table t1 (i1 int);
+insert into t1 values (1);
+create table t2 (i int);
+insert into t2 values (2);
+select 1 from t1 left join t2 b on b.i = (select max(b.i) from t2);
+drop table t1, t2;
+
+
 #
 # MDEV-12489 The select stmt may fail due to "having clause is ambiguous" unexpected
 #