weird behavior for machine epsilon in float, double and real

[Walter Bright]

Andrew Spott wrote:
> So, for the following code, I get something I think is a little off.
> I get the same value for all three variable types.  I'm kind of new
> to this, but I would think that a 32 bit would give me a different
> "smallest value" than a 64 bit or 80 bit (if real even evaluates to
> 80 bit on my machine).
> 
> What am I doing wrong, or is this a bug?

The expression: (ep + n != n) is evaluated at 80 bit precision, 
regardless of the size of its operands. The idea is that the floating 
point sizes only specify a minimum precision, and the compiler (where it 
makes sense) can use a larger precision to do constant folding and/or 
for intermediate values.

If you need the epsilon values, use float.epsilon, double.epsilon, and 
real.epsilon.