diff --git a/bitncmp.c b/bitncmp.c
index b9077bac..30891861 100644
--- a/bitncmp.c
+++ b/bitncmp.c
@@ -41,7 +41,7 @@ ares_bitncmp(const void *l, const void *r, int n) {
 
 	b = n / 8;
 	x = memcmp(l, r, b);
-	if (x)
+	if (x || (n % 8) == 0)
 		return (x);
 
 	lb = ((const unsigned char *)l)[b];