Merge mysql.com:/home/hf/work/mrg/mysql-5.0-opt

into  mysql.com:/home/hf/work/mrg/mysql-5.1-opt

mysql-test/r/func_in.result

@@ -477,6 +477,11 @@ a
 Warnings:
 Warning	1292	Incorrect date value: '19772-07-29' for column 'a' at row 1
 DROP TABLE t1,t2,t3,t4;
+CREATE TABLE t1 (id int not null);
+INSERT INTO t1 VALUES (1),(2);
+SELECT id FROM t1 WHERE id IN(4564, (SELECT IF(1=0,1,1/0)) );
+id
+DROP TABLE t1;
 End of 5.0 tests
 create table t1(f1 char(1));
 insert into t1 values ('a'),('b'),('1');

mysql-test/t/func_in.test

@@ -361,6 +361,17 @@ SELECT * FROM t4 WHERE a IN ('1972-02-06','19772-07-29');
 
 DROP TABLE t1,t2,t3,t4;
 
+#
+# BUG#27362: IN with a decimal expression that may return NULL
+#
+
+CREATE TABLE t1 (id int not null);
+INSERT INTO t1 VALUES (1),(2);
+
+SELECT id FROM t1 WHERE id IN(4564, (SELECT IF(1=0,1,1/0)) );
+
+DROP TABLE t1;
+
 --echo End of 5.0 tests
 
 

sql/item_cmpfunc.cc

@@ -2458,7 +2458,8 @@ void in_decimal::set(uint pos, Item *item)
   dec->len= DECIMAL_BUFF_LENGTH;
   dec->fix_buffer_pointer();
   my_decimal *res= item->val_decimal(dec);
-  if (res != dec)
+  /* if item->val_decimal() is evaluated to NULL then res == 0 */ 
+  if (!item->null_value && res != dec)
     my_decimal2decimal(res, dec);
 }