diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c
index 6b9cfc289d87b543b747c4024504703a2e0d6641..f38197543d80ad70ee9b0e8822a757c066e3dada 100644
--- a/builtin/pack-objects.c
+++ b/builtin/pack-objects.c
@@ -2768,7 +2768,7 @@ static void loosen_unused_packed_objects(struct rev_info *revs)
 			if (!packlist_find(&to_pack, oid.hash, NULL) &&
 			    !has_sha1_pack_kept_or_nonlocal(&oid) &&
 			    !loosened_object_can_be_discarded(&oid, p->mtime))
-				if (force_object_loose(oid.hash, p->mtime))
+				if (force_object_loose(&oid, p->mtime))
 					die("unable to force loose object");
 		}
 	}
diff --git a/cache.h b/cache.h
index d80141eb6498e4c822ee1da69bc07292f2a7e747..0a8be9c87f04f3b7147d06472637a2beb8a9a86c 100644
--- a/cache.h
+++ b/cache.h
@@ -1248,7 +1248,8 @@ extern int hash_sha1_file_literally(const void *buf, unsigned long len, const ch
 extern int pretend_object_file(void *, unsigned long, enum object_type,
 			       struct object_id *oid);
 
-extern int force_object_loose(const unsigned char *sha1, time_t mtime);
+extern int force_object_loose(const struct object_id *oid, time_t mtime);
+
 extern int git_open_cloexec(const char *name, int flags);
 #define git_open(name) git_open_cloexec(name, O_RDONLY)
 extern void *map_sha1_file(const unsigned char *sha1, unsigned long *size);
diff --git a/sha1_file.c b/sha1_file.c
index d1569b1b961c11c170b17e9011f9bb8db334a031..d9ee966d7423f2774dbcf66b92450801a28ec71b 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -1670,7 +1670,7 @@ int hash_sha1_file_literally(const void *buf, unsigned long len, const char *typ
 	return status;
 }
 
-int force_object_loose(const unsigned char *sha1, time_t mtime)
+int force_object_loose(const struct object_id *oid, time_t mtime)
 {
 	void *buf;
 	unsigned long len;
@@ -1679,13 +1679,13 @@ int force_object_loose(const unsigned char *sha1, time_t mtime)
 	int hdrlen;
 	int ret;
 
-	if (has_loose_object(sha1))
+	if (has_loose_object(oid->hash))
 		return 0;
-	buf = read_object(sha1, &type, &len);
+	buf = read_object(oid->hash, &type, &len);
 	if (!buf)
-		return error("cannot read sha1_file for %s", sha1_to_hex(sha1));
+		return error("cannot read sha1_file for %s", oid_to_hex(oid));
 	hdrlen = xsnprintf(hdr, sizeof(hdr), "%s %lu", typename(type), len) + 1;
-	ret = write_loose_object(sha1, hdr, hdrlen, buf, len, mtime);
+	ret = write_loose_object(oid->hash, hdr, hdrlen, buf, len, mtime);
 	free(buf);
 
 	return ret;