GNAT for loop can't count!

[William Paul Berriss <W.P.Berriss@reading.ac.uk>]

Hi

I use GNAT Ada95 compiler v3.07 on a Sun SPARC 5 runnig Solaris 2.5.

I have  very simple for loop that should count upwards from 118 to 129
but it counts 118, ..., 126, 127, -128, -127  (i.e. changes to
Negative after 127)

Here is the loop:

      for P in Pixel(Firstp)..Pixel(Lastp) loop             

        Ada.Integer_Text_IO.Put(Integer(P));
        Ada.Text_IO.New_line;

      end loop;

Where  Pixel is Integer range 0..255
and
Firstp and Lastp at this point are 118 and 129 respectively.
Both of type Pixel.

Very weird!

Any advice or helpful ideas most welcome indeed!!!!!!

Will Berriss
------------

-- 

W P Berriss                 E-mail: W.P.Berriss@reading.ac.uk
Department of Engineering
The University of Reading
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