--- mhash-0.9.9/lib/snefru.c	2009-01-16 00:16:04.000000000 -0500
+++ mhash-0.9.9-new/lib/snefru.c	2009-01-16 00:16:21.000000000 -0500
@@ -859,6 +859,8 @@
 {
 	mutils_word32 i;
 
+	if(!digest) return;
+
 	for (i = 0; i < len; i++, digest += 4)
 	{
 		*(mutils_word32 *)digest = mutils_bend2sys32(ctx->hash[i]);