1 files changed, 1 insertions, 1 deletions
diff --git a/pack.h b/pack.h
index aa6ee7d606..12d951659c 100644
--- a/pack.h
+++ b/pack.h
@@ -76,7 +76,7 @@ struct pack_idx_entry {
 struct progress;
 typedef int (*verify_fn)(const unsigned char*, enum object_type, unsigned long, void*, int*);
 
-extern const char *write_idx_file(const char *index_name, struct pack_idx_entry **objects, int nr_objects, const struct pack_idx_option *, unsigned char *sha1);
+extern const char *write_idx_file(const char *index_name, struct pack_idx_entry **objects, int nr_objects, const struct pack_idx_option *, const unsigned char *sha1);
 extern int check_pack_crc(struct packed_git *p, struct pack_window **w_curs, off_t offset, off_t len, unsigned int nr);
 extern int verify_pack_index(struct packed_git *);
 extern int verify_pack(struct packed_git *, verify_fn fn, struct progress *, uint32_t);