MDEV-13649: Server crashes in set_field_to_null_with_conversions or in Field::set_notnull

Item_cond did not correctly propagate with_window_func flag in the Item
tree. Without it, we would not call Item::split_sum_func correctly and the
window function's result_field would remain NULL.

mysql-test/r/win.result

@@ -3214,3 +3214,51 @@ SELECT * FROM fv_result;
 somedate
 2017-07-20 12:47:56
 DROP TABLE fv_test, fv_result;
+#
+# MDEV-13649: Server crashes in set_field_to_null_with_conversions or in Field::set_notnull
+#
+CREATE TABLE t1 (a int);
+INSERT INTO t1 VALUES (0),(1),(2);
+SELECT LEAD(a) OVER (PARTITION BY a) as lead,
+a AND LEAD(a) OVER (PARTITION BY a) AS a_and_lead_part
+FROM t1;
+lead	a_and_lead_part
+NULL	0
+NULL	NULL
+NULL	NULL
+SELECT a OR LEAD(a) OVER (ORDER BY a) AS a_or_lead_order
+FROM t1
+ORDER BY a;
+a_or_lead_order
+1
+1
+1
+SELECT a AND LEAD(a) OVER (ORDER BY a) AS a_and_lead_order
+FROM t1
+ORDER BY a;
+a_and_lead_order
+0
+1
+NULL
+SELECT a XOR LEAD(a) OVER (ORDER BY a) AS a_xor_lead_order
+FROM t1
+ORDER BY a;
+a_xor_lead_order
+1
+0
+NULL
+SELECT NOT LEAD(a) OVER (ORDER BY a) AS not_lead_order
+FROM t1
+ORDER BY a;
+not_lead_order
+0
+0
+NULL
+SELECT LEAD(a) OVER (ORDER BY a) is not null AS is_not_null_lead_order
+FROM t1
+ORDER BY a;
+is_not_null_lead_order
+1
+1
+0
+drop table t1;

mysql-test/t/win.test

@@ -1993,3 +1993,35 @@ SHOW CREATE TABLE fv_result;
 SELECT * FROM fv_result;
 
 DROP TABLE fv_test, fv_result;
+
+--echo #
+--echo # MDEV-13649: Server crashes in set_field_to_null_with_conversions or in Field::set_notnull
+--echo #
+
+CREATE TABLE t1 (a int);
+INSERT INTO t1 VALUES (0),(1),(2);
+SELECT LEAD(a) OVER (PARTITION BY a) as lead,
+       a AND LEAD(a) OVER (PARTITION BY a) AS a_and_lead_part
+FROM t1;
+
+SELECT a OR LEAD(a) OVER (ORDER BY a) AS a_or_lead_order
+FROM t1
+ORDER BY a;
+
+SELECT a AND LEAD(a) OVER (ORDER BY a) AS a_and_lead_order
+FROM t1
+ORDER BY a;
+
+SELECT a XOR LEAD(a) OVER (ORDER BY a) AS a_xor_lead_order
+FROM t1
+ORDER BY a;
+
+SELECT NOT LEAD(a) OVER (ORDER BY a) AS not_lead_order
+FROM t1
+ORDER BY a;
+
+SELECT LEAD(a) OVER (ORDER BY a) is not null AS is_not_null_lead_order
+FROM t1
+ORDER BY a;
+
+drop table t1;

sql/item_cmpfunc.cc

@@ -4635,11 +4635,11 @@ Item_cond::fix_fields(THD *thd, Item **ref)
       const_item_cache= FALSE;
     } 
   
-    with_sum_func=	    with_sum_func || item->with_sum_func;
-    with_field=             with_field || item->with_field;
+    with_sum_func|=    item->with_sum_func;
+    with_field|=       item->with_field;
     with_subselect|=   item->has_subquery();
-    if (item->maybe_null)
-      maybe_null=1;
+    with_window_func|= item->with_window_func;
+    maybe_null|=       item->maybe_null;
   }
   fix_length_and_dec();
   fixed= 1;