/* Now resolve and find the matching current branch */
        branch_name = resolve_ref_unsafe("HEAD", 0, NULL, &rru_flags);
-       if (!(rru_flags & REF_ISSYMREF))
+       if (!branch_name || !(rru_flags & REF_ISSYMREF))
                return NULL;
 
        if (!starts_with(branch_name, "refs/"))
        struct commit_list *parents;
        struct object_id *oid;
 
-       if (!opt->diff && !DIFF_OPT_TST(&opt->diffopt, EXIT_WITH_STATUS))
+       if (!opt->diff && !opt->diffopt.flags.exit_with_status)
                return 0;
 
        parse_commit_or_die(commit);