sub lint {
	my ($fn) = $_;

	$fn = decode_utf8($fn);

	if ($fn ne (my $new_fn = compose($fn))) {
		print STDERR "Decomposed unicode: $new_fn\n";
		if (!DRY_RUN) {
			die if -e $new_fn;
			rename($fn, $new_fn) or warn "Failed rename for file $fn";
		}
	}

	if (-f $fn) {