}
tree = parse_tree_indirect(old->commit ?
&old->commit->object.oid :
- &empty_tree_oid);
+ the_hash_algo->empty_tree);
init_tree_desc(&trees[0], tree->buffer, tree->size);
tree = parse_tree_indirect(&new->commit->object.oid);
init_tree_desc(&trees[1], tree->buffer, tree->size);