lseg_construct(PG_FUNCTION_ARGS)
{
	Point	   *pt1 = PG_GETARG_POINT_P(0);
	Point	   *pt2 = PG_GETARG_POINT_P(1);
	LSEG	   *result = (LSEG *) palloc(sizeof(LSEG));

	result->p[0].x = pt1->x;
	result->p[0].y = pt1->y;
	result->p[1].x = pt2->x;
	result->p[1].y = pt2->y;

#ifdef NOT_USED
	result->m = point_sl(pt1, pt2);
#endif

	PG_RETURN_LSEG_P(result);
}

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