MDEV-10716: Assertion `real_type() != FIELD_ITEM' failed in Item_ref::build_equal_items(THD*, COND_EQUAL*, bool, COND_EQUAL**)

Degenerated condition in AND should be treated in the same
way as in WHERE/HAVING alone (i.e reference should be
processed as well as fields)

mysql-test/r/having.result

@@ -709,3 +709,23 @@ c1	c2
 x	x
 DROP TABLE t1,t2;
 End of 10.0 tests
+#
+# MDEV-10716: Assertion `real_type() != FIELD_ITEM' failed in
+# Item_ref::build_equal_items(THD*, COND_EQUAL*, bool, COND_EQUAL**)
+#
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (1),(2);
+SELECT i, COUNT(*) FROM t1 GROUP BY i HAVING i<>0 AND 1;
+i	COUNT(*)
+1	1
+2	1
+SELECT i-1 A, COUNT(*) FROM t1 GROUP BY i HAVING A AND 1;
+A	COUNT(*)
+1	1
+CREATE VIEW v1 as select i, i-1 as A from t1;
+SELECT A, COUNT(*) FROM v1 GROUP BY i HAVING A AND 1;
+A	COUNT(*)
+1	1
+DROP VIEW v1;
+DROP TABLE t1;
+End of 10.1 tests

mysql-test/t/having.test

@@ -743,3 +743,18 @@ SELECT * FROM t1 JOIN t2 ON c1 = c2 HAVING c2 > 'a' ORDER BY c2 LIMIT 1;
 DROP TABLE t1,t2;
 
 --echo End of 10.0 tests
+
+--echo #
+--echo # MDEV-10716: Assertion `real_type() != FIELD_ITEM' failed in
+--echo # Item_ref::build_equal_items(THD*, COND_EQUAL*, bool, COND_EQUAL**)
+--echo #
+CREATE TABLE t1 (i INT);
+INSERT INTO t1 VALUES (1),(2);
+SELECT i, COUNT(*) FROM t1 GROUP BY i HAVING i<>0 AND 1;
+SELECT i-1 A, COUNT(*) FROM t1 GROUP BY i HAVING A AND 1;
+CREATE VIEW v1 as select i, i-1 as A from t1;
+SELECT A, COUNT(*) FROM v1 GROUP BY i HAVING A AND 1;
+DROP VIEW v1;
+DROP TABLE t1;
+
+--echo End of 10.1 tests

sql/item_cmpfunc.cc

@@ -4507,7 +4507,8 @@ Item_cond::fix_fields(THD *thd, Item **ref)
         was:    <field>
         become: <field> = 1
     */
-    if (item->type() == FIELD_ITEM)
+    Item::Type type= item->type();
+    if (type == Item::FIELD_ITEM || type == Item::REF_ITEM)
     {
       Query_arena backup, *arena;
       Item *new_item;