+
+ if (!cmd->expire_unreachable || !strcmp(ref, "HEAD")) {
+ tip_commit = NULL;
+ cb.unreachable_expire_kind = UE_HEAD;
+ } else {
+ tip_commit = lookup_commit_reference_gently(sha1, 1);
+ if (!tip_commit)
+ cb.unreachable_expire_kind = UE_ALWAYS;
+ else
+ cb.unreachable_expire_kind = UE_NORMAL;
+ }
+
+ if (cmd->expire_unreachable <= cmd->expire_total)
+ cb.unreachable_expire_kind = UE_ALWAYS;
+
+ cb.mark_list = NULL;
+ tips = NULL;
+ if (cb.unreachable_expire_kind != UE_ALWAYS) {
+ if (cb.unreachable_expire_kind == UE_HEAD) {
+ struct commit_list *elem;
+ for_each_ref(push_tip_to_list, &tips);
+ for (elem = tips; elem; elem = elem->next)
+ commit_list_insert(elem->item, &cb.mark_list);
+ } else {
+ commit_list_insert(tip_commit, &cb.mark_list);
+ }
+ cb.mark_limit = cmd->expire_total;
+ mark_reachable(&cb);
+ }
+