MDEV-19164 Assertion `fixed' failed in Item_func_inet_aton::val_int

When pushing a condition from HAVING into WHERE the function
st_select_lex::pushdown_from_having_into_where() transforms column
references in the pushed condition then performs cleanup of
items of the condition and finally calls fix_fields() for the condition
items. The cleanup is performed by a call of the method walk() with
cleanup_processor as the first parameter. Unfortunately this sequence
of calls does not work if the condition contains cached items, because
fix_fields() cannot go through Item_cache items and this leaves
underlying items unfixed.
The solution of this problem used in this patch is just does not allow
to process Item_cache objects when performing cleanup of the pushed
condition. In order to let the traversal procedure walk() not to process
Item_cache objects the third parameter of the used call of walk()
is set to a fictitious pointer (void *) 1. And Item_cache::walk() is
changed to prevent any action when it gets such value as the third
parameter.

1 files changed, 76 insertions, 0 deletions

diff --git a/mysql-test/main/having_cond_pushdown.result b/mysql-test/main/having_cond_pushdown.result
index 85ca0342dee..d7c9d936627 100644
--- a/mysql-test/main/having_cond_pushdown.result
+++ b/mysql-test/main/having_cond_pushdown.result
@@ -4657,3 +4657,79 @@ GROUP BY v1.pk
 HAVING (v1.pk = 1);
 DROP TABLE t1,t2,tmp1;
 DROP VIEW v1;
+#
+# MDEV-19164: pushdown of condition with cached items
+#
+create table t1 (d1 date);
+insert into t1 values (null),('1971-03-06'),('1993-06-05'),('1998-07-08');
+select d1 from t1
+group by d1
+having d1 between (inet_aton('1978-04-27')) and '2018-08-26';
+d1
+explain extended select d1 from t1
+group by d1
+having d1 between (inet_aton('1978-04-27')) and '2018-08-26';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	4	100.00	Using where; Using temporary; Using filesort
+Warnings:
+Note	1003	select `test`.`t1`.`d1` AS `d1` from `test`.`t1` where `test`.`t1`.`d1` between <cache>(inet_aton('1978-04-27')) and <cache>('2018-08-26') group by `test`.`t1`.`d1` having 1
+explain format=json select d1 from t1
+group by d1
+having d1 between (inet_aton('1978-04-27')) and '2018-08-26';
+EXPLAIN
+{
+  "query_block": {
+    "select_id": 1,
+    "filesort": {
+      "sort_key": "t1.d1",
+      "temporary_table": {
+        "table": {
+          "table_name": "t1",
+          "access_type": "ALL",
+          "rows": 4,
+          "filtered": 100,
+          "attached_condition": "t1.d1 between <cache>(inet_aton('1978-04-27')) and <cache>('2018-08-26')"
+        }
+      }
+    }
+  }
+}
+delete from t1;
+insert into t1 values ('2018-01-15'),('2018-02-20');
+select d1 from t1
+group by d1
+having d1 not between 0 AND exp(0);
+d1
+2018-01-15
+2018-02-20
+Warnings:
+Warning	1292	Truncated incorrect datetime value: '1'
+explain extended select d1 from t1
+group by d1
+having d1 not between 0 AND exp(0);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	2	100.00	Using where; Using temporary; Using filesort
+Warnings:
+Note	1003	select `test`.`t1`.`d1` AS `d1` from `test`.`t1` where `test`.`t1`.`d1` not between <cache>(0) and <cache>(exp(0)) group by `test`.`t1`.`d1` having 1
+explain format=json select d1 from t1
+group by d1
+having d1 not between 0 AND exp(0);
+EXPLAIN
+{
+  "query_block": {
+    "select_id": 1,
+    "filesort": {
+      "sort_key": "t1.d1",
+      "temporary_table": {
+        "table": {
+          "table_name": "t1",
+          "access_type": "ALL",
+          "rows": 2,
+          "filtered": 100,
+          "attached_condition": "t1.d1 not between <cache>(0) and <cache>(exp(0))"
+        }
+      }
+    }
+  }
+}
+drop table t1;