--- ../src/src/hash_SHA2_template.c	2015-07-15 15:25:59.000000000 +0530
+++ src/hash_SHA2_template.c	2015-07-17 15:35:13.000000000 +0530
@@ -87,7 +87,7 @@
  * return 1 on success
  * return 0 if the length overflows
  */
-static int add_length(hash_state *hs, sha2_word_t inc) {
+int add_length(hash_state *hs, sha2_word_t inc) {
     sha2_word_t overflow_detector;
     overflow_detector = hs->length_lower;
     hs->length_lower += inc;