lseg_send(PG_FUNCTION_ARGS)
{
	LSEG	   *ls = PG_GETARG_LSEG_P(0);
	StringInfoData buf;

	pq_begintypsend(&buf);
	pq_sendfloat8(&buf, ls->p[0].x);
	pq_sendfloat8(&buf, ls->p[0].y);
	pq_sendfloat8(&buf, ls->p[1].x);
	pq_sendfloat8(&buf, ls->p[1].y);
	PG_RETURN_BYTEA_P(pq_endtypsend(&buf));
}

This weakness involves numeric computation errors, such as integer overflows, underflows, or precision losses, which can lead to miscalculations and exploitable behaviors in software.