diff --git a/blame.c b/blame.c
index 98f99922a7..9bb34e63ec 100644
--- a/blame.c
+++ b/blame.c
@@ -813,6 +813,7 @@ int main(int argc, const char **argv)
 	rev.prune_fn = simplify_commit;
 	rev.topo_setter = topo_setter;
 	rev.topo_getter = topo_getter;
+	rev.parents = 1;
 	rev.limited = 1;
 
 	commit_list_insert(start_commit, &rev.commits);