usage(builtin_diff_usage);
 
        if (lstat(path, &st))
-               die("'%s': %s", path, strerror(errno));
+               die_errno("failed to stat '%s'", path);
        if (!(S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)))
                die("'%s': not a regular file or symlink", path);
 
                        revs->max_count = 3;
                else if (!strcmp(argv[1], "-q"))
                        options |= DIFF_SILENT_ON_REMOVED;
+               else if (!strcmp(argv[1], "-h"))
+                       usage(builtin_diff_usage);
                else
                        return error("invalid option: %s", argv[1]);
                argv++; argc--;