diff --git a/src/vty/utils.c b/src/vty/utils.c
index a651515..0f5a34e 100644
--- a/src/vty/utils.c
+++ b/src/vty/utils.c
@@ -415,6 +415,7 @@
 	if (ret < 0)
 		goto err;
 	OSMO_SNPRINTF_RET(ret, rem, offset, len);
+	(void)len; /* suppress warnings about len being set but not used */
 err:
 	str[size-1] = '\0';
 	return str;