on_ppath(PG_FUNCTION_ARGS)
{
	Point	   *pt = PG_GETARG_POINT_P(0);
	PATH	   *path = PG_GETARG_PATH_P(1);
	int			i,
				n;
	double		a,
				b;

	/*-- OPEN --*/
	if (!path->closed)
	{
		n = path->npts - 1;
		a = point_dt(pt, &path->p[0]);
		for (i = 0; i < n; i++)
		{
			b = point_dt(pt, &path->p[i + 1]);
			if (FPeq(a + b,
					 point_dt(&path->p[i], &path->p[i + 1])))
				PG_RETURN_BOOL(true);
			a = b;
		}
		PG_RETURN_BOOL(false);
	}

	/*-- CLOSED --*/
	PG_RETURN_BOOL(point_inside(pt, path->npts, path->p) != 0);
}

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