1 files changed, 1 insertions, 1 deletions

diff --git a/delta.c b/delta.c
index b31957a1d3..db85989e71 100644
--- a/delta.c
+++ b/delta.c
@@ -17,7 +17,7 @@ struct delta {
 	} u;
 };
 
-struct delta *lookup_delta(unsigned char *sha1)
+struct delta *lookup_delta(const unsigned char *sha1)
 {
 	struct object *obj = lookup_object(sha1);
 	if (!obj) {