diff --git a/t/helper/test-ref-store.c b/t/helper/test-ref-store.c
index 05d8c4d8af..6ec2670044 100644
--- a/t/helper/test-ref-store.c
+++ b/t/helper/test-ref-store.c
@@ -135,7 +135,7 @@ static int cmd_resolve_ref(struct ref_store *refs, const char **argv)
 
 	ref = refs_resolve_ref_unsafe(refs, refname, resolve_flags,
 				      sha1, &flags);
-	printf("%s %s 0x%x\n", sha1_to_hex(sha1), ref, flags);
+	printf("%s %s 0x%x\n", sha1_to_hex(sha1), ref ? ref : "(null)", flags);
 	return ref ? 0 : 1;
 }