MDEV-76 5.5 memory overrun on main.select_jcl6.

geometry fields are blobs too.

mysql-test/r/select_jcl6.result

@@ -4411,7 +4411,7 @@ INSERT INTO t1 VALUES
 EXPLAIN SELECT 1 FROM t1 NATURAL LEFT JOIN t1 AS t2;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	2	
-1	SIMPLE	t2	hash_ALL	a	#hash#$hj	12	test.t1.a	2	Using where; Using join buffer (flat, BNLH join)
+1	SIMPLE	t2	hash_ALL	a	#hash#$hj	14	test.t1.a	2	Using where; Using join buffer (flat, BNLH join)
 SELECT 1 FROM t1 NATURAL LEFT JOIN t1 AS t2;
 1
 1
@@ -4421,7 +4421,7 @@ SELECT 1 FROM t1 NATURAL LEFT JOIN t1 AS t2;
 EXPLAIN SELECT 1 FROM t1 NATURAL LEFT JOIN t1 AS t2 FORCE INDEX(a);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	2	
-1	SIMPLE	t2	hash_ALL	a	#hash#$hj	12	test.t1.a	2	Using where; Using join buffer (flat, BNLH join)
+1	SIMPLE	t2	hash_ALL	a	#hash#$hj	14	test.t1.a	2	Using where; Using join buffer (flat, BNLH join)
 SELECT 1 FROM t1 NATURAL LEFT JOIN t1 AS t2 FORCE INDEX(a);
 1
 1

sql/table.cc

@@ -5621,6 +5621,7 @@ void TABLE::create_key_part_by_field(KEY *keyinfo,
     keyinfo->key_length+= HA_KEY_NULL_LENGTH;
   }
   if (field->type() == MYSQL_TYPE_BLOB || 
+      field->type() == MYSQL_TYPE_GEOMETRY ||
       field->real_type() == MYSQL_TYPE_VARCHAR)
   {
     key_part_info->store_length+= HA_KEY_BLOB_LENGTH;