Re: setting an address with pure?

["Randy Brukardt" <randy@rrsoftware.com>]

"Simon Wright" <simon@pushface.org> wrote in message 
news:lyy4iokzci.fsf@pushface.org...
>I need to specify the address at which a hardware object appears.
>
> This works:
>
>   PIOA : PIO
>     with
>       Import,
>       Convention => Ada,
>       Address => System.Storage_Elements.To_Address (16#400E0E00#);
>
> but means that I can't declare the package Pure (or even Preelaborate).

You can't have a variable at library level in a Pure package (there shall be 
no state), so it makes no sense at all for such a package to contain any 
hardware objects.

I don't see any reason why this can't be Preelaborated 
(System.Storage_Elements is Pure, after all); that depends on the 
initialization of the type PIO (it needs to have 
"preelaborable_initialization"; use the pragma if in doubt).

                            Randy.