Victor, this is fp_setreadl's problem, so if put "tok->lineno = -1"
anywhere, it should be in fp_setreadl(), I think.

	r = set_readline(tok, cs);
	if (r) {
		/* 1 */
		tok->encoding = cs;
		tok->decoding_state = STATE_NORMAL;

At /* 1 */, set_readline could be buf_setreadl(), and fp_setreadl is
called elsewhere.