Re: Weird controlled behavior - Gnat 3.15p NT

[Martin Krischik <krischik@users.sourceforge.net>]

Jano wrote:

> Hello,
> 
> see the following type declarations and lines of code:
> 
>    type Object is abstract new
>       Finalization.Controlled with null record;
>    type Object_access is access all Object'Class;
> 
>    procedure Initialize (This : in out Object) is
>    begin
>       Trace.Log ("====>");
>    end Initialize;

Try to add:

procedure Adjust (This : in out Object) is
   begin
     Trace.Log ("<===>");
   end Adjust;

and Test again.

>    procedure Finalize   (This : in out Object) is
>    begin
>       Trace.Log ("<====");
>    end Finalize;
> 
>    declare
>       -- THIS LINE IS THE RELEVANT ONE.
>       Thing : Object_access :=
>          new Object'Class'(Object'Class'Input (Stream));
>    begin
>       null;
>    end;
> 
> Ok, running normally or stepping with GVD when the line with the
> stream reading is executed I get the following log:
> 
> ====>
> <====
> <====
> <====
> 
> Compiled with -O2 and without it if that means something. Consistently
> with each object in the stream.
> 
> Now, I would assume that no Finalization could happen without a
> corresponding Initialization, so is this normal? Is something wrong in
> that read way?

Yes, types may be Adjusted without Initialization. Has been (and still is) 
a major headache in the design of AdaCL.Trace
(http://adacl.sourceforge.net/html/______Include__AdaCL-Trace__adb.htm).

With Regards

Martin

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