Re: Preventing Unchecked_Deallocation?

[Adam Beneschan <adam@irvine.com>]

On Feb 6, 4:52 am, Julian Leyh <jul...@vgai.de> wrote:
> On 5 Feb., 17:42, Simon Belmont <sbelmont...@gmail.com> wrote:
>
> > package ud is
> >   function Get return not null access Integer;
> > end ud;
>
> > package body ud is
> >   type Int_Ptr is access all Integer;
> >   o : Int_Ptr := new Integer'(42);
>
> use o : constant Int_Ptr := ....

Ummm, no.  All that does is prevent the variable "o" from being
modified inside the body of UD.  That means that if Free is an
instance of Unchecked_Deallocation, the body of UD can't call

   Free (o);

but that doesn't prevent

   x := o;       -- where x is a variable
   Free (x);

or

   x := Get;
   Free (x);

And "o" will point to a non-existing object.

                            -- Adam