"Polygon not closed" warning - rounding error?

[Philipp K. J. <ja...@ie...>]

If I issue the following two commands (in a fresh
5.0rc3 session):

set object 1 polygon from -0.9,0.9 rto 0.8,0 rto 0,-0.8 rto -0.8,0 rto
0,0.8

set object 2 polygon from  0.1,0.9 rto 0.8,0 rto 0,-0.8 rto -0.8,0 rto
0,0.8

then gnuplot complains that the second polygon is
not closed (and that gnuplot is adding a vertex).

Which is funny, because the relative displacements
are exactly the same for both polygons, only the
origin is different. (They also look the same.)

What causes this warning? Is this due to internal
roundoff, so that the endpoint != startpoint in
floating point arithmetic?

It did confuse me for a while (did I do something
wrong?). Might it be possible to suppress such 
warnings?

Best,

		Ph.