diff --git a/evdns.c b/evdns.c
index 905ff6b..e9dbc35 100644
--- a/evdns.c
+++ b/evdns.c
@@ -3175,9 +3175,12 @@ search_set_from_hostname(struct evdns_base *base) {
 static char *
 search_make_new(const struct search_state *const state, int n, const char *const base_name) {
 	const size_t base_len = strlen(base_name);
-	const char need_to_append_dot = base_name[base_len - 1] == '.' ? 0 : 1;
+	char need_to_append_dot;
 	struct search_domain *dom;
 
+	if (!base_len) return NULL;
+	need_to_append_dot = base_name[base_len - 1] == '.' ? 0 : 1;
+
 	for (dom = state->head; dom; dom = dom->next) {
 		if (!n--) {
 			/* this is the postfix we want */