diff --git a/skeletons/tests/check-length.c b/skeletons/tests/check-length.c
index d0edde37a8e6b6d4ba50e6b6fdbe4eea5ce993ac..7746bcf305e51b5c3bb9b6a1c5779c5467693fee 100644
--- a/skeletons/tests/check-length.c
+++ b/skeletons/tests/check-length.c
@@ -58,7 +58,7 @@ check(int size) {
 	assert(erval.encoded == buf_off);
 	assert(buf_off > size);
 
-	rval = ber_decode(&asn1_DEF_OCTET_STRING, &nos, buf, buf_off);
+	rval = ber_decode(&asn1_DEF_OCTET_STRING, (void **)&nos, buf, buf_off);
 	assert(rval.code == RC_OK);
 	assert(rval.consumed == buf_off);