Re: How many Ada compiler bugs are here?

[Adam Beneschan <adam@irvine.com>]

On Jan 13, 12:06 pm, Blady <p....@orange.fr> wrote:
>
> > > 1. Adjust should not be allowed to be declared (it is a *limited*
> > > type). But I have defined it to trace the remaining bugs:
>
> > There's nothing wrong with defining "Adjust" (you can define any named
> > subprogram you want, of course), but (A) "overriding" shouldn't be allowed
> > on it, and (B) it shouldn't be called automatically if it is defined without
> > "overriding", because it is not special for a limited type.

> Hello,
> back to point 1), assuming GNAT is used, the private spec of
> Ada.Finalization is
>    package SFR renames System.Finalization_Root;
>    type Controlled is abstract new SFR.Root_Controlled with null
> record;
>    --  In order to simplify the implementation, the mechanism in
> Process_Full_
>    --  View ensures that the full view is limited even though the
> parent type
>    --  is not.
>    type Limited_Controlled is
>      abstract new SFR.Root_Controlled with null record;
> and
>    type Root_Controlled is tagged null record;
>    procedure Adjust     (Object : in out Root_Controlled);
>    procedure Finalize   (Object : in out Root_Controlled);
>    procedure Initialize (Object : in out Root_Controlled);
> So with GNAT Adjust is part of Limited_Controlled primitives, isn't
> it?
>
> Best, Pascal.

Since Limited_Controlled is derived from SFR.Root_Controlled in the
*private* part of Ada.Finalization, any primitive operations that get
inherited shouldn't be visible to any place that can't see the private
part of Ada.Finalization; and therefore this should not affect the
legality of anything.  Maciej's package says

  overriding procedure Adjust (...)

which is illegal because Adjust isn't supposed to be visible to his
package.  If GNAT is accepting this, this means that some stuff that
should be invisible is visible, and that's a bug.

                              -- Adam