lp:736791 Crash in make_truncated_value_warningwith LEAST()/GREATEST/COALESCE

and a test case for lp:736370 Datetime functions in subquery context cause wrong result

mysql-test/r/func_time.result

@@ -1476,3 +1476,21 @@ Warning	1292	Truncated incorrect time value: '-596523:14:07'
 select convert_tz(timediff('0000-00-00 00:00:00', cast('2008-03-26 07:09:06' as datetime)), 'UTC', 'Europe/Moscow');
 convert_tz(timediff('0000-00-00 00:00:00', cast('2008-03-26 07:09:06' as datetime)), 'UTC', 'Europe/Moscow')
 NULL
+create table t1 (f1 integer, f2 date);
+insert into t1 values (1,'2011-05-05'),(2,'2011-05-05'),(3,'2011-05-05'),(4,'2011-05-05'),(5,'2011-05-05');
+select * from t1 where (f1, f2) in (select f1, makedate(2011 , 125) from t1);
+f1	f2
+1	2011-05-05
+2	2011-05-05
+3	2011-05-05
+4	2011-05-05
+5	2011-05-05
+drop table t1;
+create table t1 (f1 timestamp);
+insert into t1 values ('0000-00-00 00:00:00');
+select least(1, f1) from t1;
+least(1, f1)
+0000-00-00 00:00:00
+Warnings:
+Warning	1292	Incorrect datetime value: '1' for column 'f1' at row 1
+drop table t1;

mysql-test/t/func_time.test

@@ -916,3 +916,19 @@ drop table t1;
 #
 select timediff('0000-00-00 00:00:00', cast('2008-03-26 07:09:06' as datetime));
 select convert_tz(timediff('0000-00-00 00:00:00', cast('2008-03-26 07:09:06' as datetime)), 'UTC', 'Europe/Moscow');
+
+#
+# lp:736370 Datetime functions in subquery context cause wrong result and bogus warnings in mysql-5.1-micr
+#
+create table t1 (f1 integer, f2 date);
+insert into t1 values (1,'2011-05-05'),(2,'2011-05-05'),(3,'2011-05-05'),(4,'2011-05-05'),(5,'2011-05-05');
+select * from t1 where (f1, f2) in (select f1, makedate(2011 , 125) from t1);
+drop table t1;
+
+#
+# lp:736791 Crash in make_truncated_value_warningwith LEAST()/GREATEST/COALESCE
+#
+create table t1 (f1 timestamp);
+insert into t1 values ('0000-00-00 00:00:00');
+select least(1, f1) from t1;
+drop table t1;

sql/item_func.cc

@@ -2221,6 +2221,7 @@ void Item_func_min_max::fix_length_and_dec()
   decimals=0;
   max_length=0;
   maybe_null=0;
+  thd= current_thd;
   cmp_type=args[0]->result_type();
 
   for (uint i=0 ; i < arg_count ; i++)
@@ -2240,8 +2241,6 @@ void Item_func_min_max::fix_length_and_dec()
   if (cmp_type == STRING_RESULT)
   {
     agg_arg_charsets(collation, args, arg_count, MY_COLL_CMP_CONV, 1);
-    if (compare_as_dates)
-      thd= current_thd;
   }
   else if ((cmp_type == DECIMAL_RESULT) || (cmp_type == INT_RESULT))
     max_length= my_decimal_precision_to_length_no_truncation(max_int_part +