--- a/getifname.c
+++ b/getifname.c
@@ -59,7 +59,7 @@ int get_if_name(void)
 			known_output_if = 1;
 			if (opt_debug)
 				printf("DEBUG: Output interface address: %s\n",
-					inet_ntoa(sa.sin_addr));
+					inet_ntoa(output_if_addr.sin_addr));
 		} else {
 			fprintf(stderr, "Warning: Unable to guess the output "
 					"interface\n");