diff --git a/lib/dns/name.c b/lib/dns/name.c
index b6657f620a..f751b9a067 100644
--- a/lib/dns/name.c
+++ b/lib/dns/name.c
@@ -1264,6 +1264,7 @@ dns_name_fromtext(dns_name_t *name, isc_buffer_t *source,
 		}
 		if (state == ft_ordinary) {
 			INSIST(count != 0);
+			INSIST(label != NULL);
 			*label = count;
 			labels++;
 			INSIST(labels <= 127);