diff --git a/mysql-test/r/type_newdecimal.result b/mysql-test/r/type_newdecimal.result
index b406dbab82f..79943df18c5 100644
--- a/mysql-test/r/type_newdecimal.result
+++ b/mysql-test/r/type_newdecimal.result
@@ -928,3 +928,9 @@ select * from t1 where a = -0.00;
 a
 0.00
 drop table t1;
+create table t1 (col1 bigint default -9223372036854775808);
+insert into t1 values (default);
+select * from t1;
+col1
+-9223372036854775808
+drop table t1;
diff --git a/mysql-test/t/type_newdecimal.test b/mysql-test/t/type_newdecimal.test
index 6199bd34fa9..5c4f288983b 100644
--- a/mysql-test/t/type_newdecimal.test
+++ b/mysql-test/t/type_newdecimal.test
@@ -964,3 +964,12 @@ insert into t1 values (0.00);
 select * from t1 where a > -0.00;
 select * from t1 where a = -0.00;
 drop table t1;
+
+#
+# Bug #11215: a problem with LONGLONG_MIN
+#
+
+create table t1 (col1 bigint default -9223372036854775808);
+insert into t1 values (default);
+select * from t1;
+drop table t1;
diff --git a/sql/item.cc b/sql/item.cc
index d3888cef9d5..82edc05c721 100644
--- a/sql/item.cc
+++ b/sql/item.cc
@@ -3573,7 +3573,7 @@ Item *Item_int_with_ref::new_item()
 
 Item_num *Item_uint::neg()
 {
-  Item_decimal *item= new Item_decimal(value, 0);
+  Item_decimal *item= new Item_decimal(value, 1);
   return item->neg();
 }