Re: Rep-spec question

[Tucker Taft <stt@averstar.com>]

Joe Wisniewski wrote:
> 
> Given the following:
> 
> type Rec is
>    b : boolean;
> end record;
> 
> for rec use record
>    b at 0 range 0..63;
> end record;
> for rec'size use 64;
> 
> can any assumptions be made as to where the
> byte(s) representing the boolean are stored?

You can pretty safely assume that an enumeration value is stored in
the low-order bits of the 64-bit component you have specified.  I would
expect this only to be supported on implementations that support
64-bit integers.

Another interesting question is what are the representations of False and
True.  I suspect that on some targets, True is all ones, while False is
zero.  On such a target, the answer to your question is "any byte". ;-)

> 
> Joe

-Tuck
-- 
-Tucker Taft   stt@averstar.com   http://www.averstar.com/~stt/
Technical Director, Distributed IT Solutions  (www.averstar.com/tools)
AverStar (formerly Intermetrics, Inc.)   Burlington, MA  USA