bug#21873 MySQLD Crash on ALTER...ADD..UNIQUE..USING HASH statement for NDB backed table: Use passed key_info to check for nullable fields

mysql-test/r/ndb_index_unique.result

@@ -639,3 +639,6 @@ select a, sha1(b) from t1;
 a	sha1(b)
 1	08f5d02c8b8bc244f275bdfc22c42c5cab0d9d7d
 drop table t1;
+create table t1(id int not null) engine = NDB;
+alter table t1 add constraint uk_test unique (id) using hash;
+drop table t1;

mysql-test/t/ndb_index_unique.test

@@ -329,4 +329,12 @@ select a, sha1(b) from t1;
 
 drop table t1;
 
+# bug#21873 MySQLD Crash on ALTER...ADD..UNIQUE..USING HASH statement for NDB backed table
+
+create table t1(id int not null) engine = NDB;
+
+alter table t1 add constraint uk_test unique (id) using hash;
+
+drop table t1;
+
 # End of 4.1 tests

sql/ha_ndbcluster.cc

@@ -1399,9 +1399,8 @@ NDB_INDEX_TYPE ha_ndbcluster::get_index_type_from_key(uint inx,
           ORDERED_INDEX);
 } 
 
-int ha_ndbcluster::check_index_fields_not_null(uint inx)
+int ha_ndbcluster::check_index_fields_not_null(KEY* key_info)
 {
-  KEY* key_info= table->key_info + inx;
   KEY_PART_INFO* key_part= key_info->key_part;
   KEY_PART_INFO* end= key_part+key_info->key_parts;
   DBUG_ENTER("ha_ndbcluster::check_index_fields_not_null");
@@ -5016,7 +5015,7 @@ int ha_ndbcluster::create_index(const char *name, KEY *key_info,
       error= create_unique_index(unique_name, key_info);
     break;
   case UNIQUE_INDEX:
-    if (!(error= check_index_fields_not_null(idx_no)))
+    if (!(error= check_index_fields_not_null(key_info)))
       error= create_unique_index(unique_name, key_info);
     break;
   case ORDERED_INDEX:

sql/ha_ndbcluster.h

@@ -808,7 +808,7 @@ private:
   NDB_INDEX_TYPE get_index_type_from_table(uint index_no) const;
   NDB_INDEX_TYPE get_index_type_from_key(uint index_no, KEY *key_info, 
                                          bool primary) const;
-  int check_index_fields_not_null(uint index_no);
+  int check_index_fields_not_null(KEY *key_info);
 
   uint set_up_partition_info(partition_info *part_info,
                              TABLE *table,