Re: Memory Access

[Adam Beneschan <adam@irvine.com>]

On Nov 7, 3:13 pm, Simon Wright <si...@pushface.org> wrote:
> Adam Beneschan <a...@irvine.com> writes:
> >     declare
> >        Dev_Table : Dev_Table_Type (1 .. Num_Devs_Cnst);
> >        for Dev_Table'Address use Data_Address;
> >     begin
> >        -- and you can use Dev_Table in here
> >     end;
>
> One thing to be wary of here is that Dev_Table might contain initialised
> components.
>
>    type Integer_P is access all integer;
>    type Rec is record
>       I : Integer_P;
>    end record;
>    R : Rec;
>    for R'Address use ...;
>
> may well get R.I initialised to null.
>
> I don't know whether it's a GNAT convention, but the way to avoid this
> in GNAT is to add
>
>    pragma Import (Ada, R);

Yes, I forgot that; my example above should include pragma Import
(Ada, Dev_Table).  I think this is in the RM.  It isn't GNAT-specific.

                           -- Adam