Bug#11766212 59270: NOT IN (YEAR( ... ), ... ) PRODUCES MANY VALGRIND WARNINGS

Valgrind warning happens due to early null values check
in Item_func_in::fix_length_and_dec(before item evaluation).
As result null value items with uninitialized values are
placed into array and it leads to valgrind warnings during
value array sorting.
The fix is to check null value after item evaluation, item
is evaluated in in_array::set() method.

mysql-test/r/func_in.result

@@ -770,4 +770,10 @@ CASE a WHEN a THEN a END
 NULL
 DROP TABLE t1;
 #
+# Bug #11766212  59270: NOT IN (YEAR( ... ), ... ) PRODUCES MANY VALGRIND WARNINGS
+#
+SELECT 1 IN (YEAR(FROM_UNIXTIME(NULL)) ,1);
+1 IN (YEAR(FROM_UNIXTIME(NULL)) ,1)
+1
+#
 End of 5.1 tests

mysql-test/t/func_in.test

@@ -554,6 +554,12 @@ SELECT CASE a WHEN a THEN a END FROM t1 GROUP BY a WITH ROLLUP;
 
 DROP TABLE t1;
 
+--echo #
+--echo # Bug #11766212  59270: NOT IN (YEAR( ... ), ... ) PRODUCES MANY VALGRIND WARNINGS
+--echo #
+
+SELECT 1 IN (YEAR(FROM_UNIXTIME(NULL)) ,1);
+
 --echo #
 
 --echo End of 5.1 tests

sql/item_cmpfunc.cc

@@ -4000,13 +4000,11 @@ void Item_func_in::fix_length_and_dec()
       uint j=0;
       for (uint i=1 ; i < arg_count ; i++)
       {
-	if (!args[i]->null_value)			// Skip NULL values
-        {
-          array->set(j,args[i]);
-	  j++;
-        }
-	else
-	  have_null= 1;
+        array->set(j,args[i]);
+        if (!args[i]->null_value)                      // Skip NULL values
+          j++;
+        else
+          have_null= 1;
       }
       if ((array->used_count= j))
 	array->sort();