diff --git a/builtin/commit.c b/builtin/commit.c
index 8e93802..4bbac01 100644
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -510,7 +510,7 @@ static int run_status(FILE *fp, const char *index_file, const char *prefix, int
 	s->index_file = index_file;
 	s->fp = fp;
 	s->nowarn = nowarn;
-	s->is_initial = get_sha1(s->reference, oid.hash) ? 1 : 0;
+	s->is_initial = get_oid(s->reference, &oid) ? 1 : 0;
 	if (!s->is_initial)
 		hashcpy(s->sha1_commit, oid.hash);
 	s->status_format = status_format;
@@ -891,7 +891,7 @@ static int prepare_to_commit(const char *index_file, const char *prefix,
 		if (amend)
 			parent = "HEAD^1";
 
-		if (get_sha1(parent, oid.hash)) {
+		if (get_oid(parent, &oid)) {
 			int i, ita_nr = 0;
 
 			for (i = 0; i < active_nr; i++)
@@ -1387,7 +1387,7 @@ int cmd_status(int argc, const char **argv, const char *prefix)
 
 	fd = hold_locked_index(&index_lock, 0);
 
-	s.is_initial = get_sha1(s.reference, oid.hash) ? 1 : 0;
+	s.is_initial = get_oid(s.reference, &oid) ? 1 : 0;
 	if (!s.is_initial)
 		hashcpy(s.sha1_commit, oid.hash);
 
@@ -1657,7 +1657,7 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
 	status_format = STATUS_FORMAT_NONE; /* Ignore status.short */
 	s.colopts = 0;
 
-	if (get_sha1("HEAD", oid.hash))
+	if (get_oid("HEAD", &oid))
 		current_head = NULL;
 	else {
 		current_head = lookup_commit_or_die(&oid, "HEAD");