From: Brian Rogoff <bpr@shell5.ba.best.com>
Subject: Re: Subverting 'Access for Sub-programs
Date: 1999/08/10
Date: 1999-08-10T00:00:00+00:00 [thread overview]
Message-ID: <Pine.BSF.4.10.9908102006320.1888-100000@shell5.ba.best.com> (raw)
In-Reply-To: wcc7ln56pzx.fsf@world.std.com
On Mon, 9 Aug 1999, Robert A Duff wrote:
> Brian Rogoff <bpr@shell5.ba.best.com> writes:
>
> > So, only allow this for descendants of (possibly limited) Controlled
> > types, or some similar special type?
>
> I don't see how that helps. If you have a global "type Ptr is access
> all Something'Class", and you have a (illegal in Ada) type extension
> local to some procedure, then you could end up with a global pointer
> referencing an object of the local type (ie with the local 'Tag).
> Finalizing it doesn't make any difference -- you still have a pointer to
> a thing that contains dangling pointers (to the primitive ops).
Yup, I know you can't use finalization to get this; I thought you were
proposing a similar "distinguished tagged type" mechanism analogous to
controlled types for nested extensions, but on rereading what you wrote
I think that I must have hallucinated it :-).
In any case, I still think nested type extensions are a lot less useful
than a direct downward funarg capability.
-- Brian
next prev parent reply other threads:[~1999-08-10 0:00 UTC|newest]
Thread overview: 68+ messages / expand[flat|nested] mbox.gz Atom feed top
1999-08-03 0:00 Subverting 'Access for Sub-programs Anton Gibbs
1999-08-03 0:00 ` tmoran
1999-08-03 0:00 ` Steve Doiel
1999-08-03 0:00 ` Ted Dennison
1999-08-03 0:00 ` David C. Hoos, Sr.
1999-08-05 0:00 ` Robert A Duff
1999-08-03 0:00 ` Michael F. Yoder
1999-08-03 0:00 ` Brian Rogoff
1999-08-04 0:00 ` Robert Dewar
1999-08-04 0:00 ` Robert A Duff
1999-08-04 0:00 ` Robert Dewar
1999-08-04 0:00 ` Anton Gibbs
1999-08-04 0:00 ` Robert A Duff
1999-08-04 0:00 ` Brian Rogoff
1999-08-05 0:00 ` tmoran
1999-08-05 0:00 ` Robert Dewar
1999-08-05 0:00 ` Ray Blaak
1999-08-06 0:00 ` Robert Dewar
1999-08-06 0:00 ` Robert A Duff
1999-08-08 0:00 ` Brian Rogoff
1999-08-09 0:00 ` Robert A Duff
1999-08-10 0:00 ` Brian Rogoff [this message]
1999-08-09 0:00 ` Tucker Taft
1999-08-06 0:00 ` Jean-Pierre Rosen
1999-08-06 0:00 ` Hyman Rosen
1999-08-07 0:00 ` Florian Weimer
1999-08-05 0:00 ` Aidan Skinner
1999-08-05 0:00 ` Anton Gibbs
1999-08-04 0:00 ` Jean-Pierre Rosen
1999-08-04 0:00 ` Brian Rogoff
1999-08-05 0:00 ` Jean-Pierre Rosen
1999-08-05 0:00 ` Robert A Duff
1999-08-05 0:00 ` tmoran
1999-08-06 0:00 ` Robert A Duff
1999-08-05 0:00 ` Brian Rogoff
1999-08-06 0:00 ` Robert Dewar
1999-08-09 0:00 ` Tucker Taft
1999-08-10 0:00 ` Robert Dewar
1999-08-11 0:00 ` Tucker Taft
1999-08-13 0:00 ` Robert Dewar
1999-08-13 0:00 ` Robert Dewar
1999-08-13 0:00 ` Brian Rogoff
1999-08-11 0:00 ` Robert A Duff
1999-08-11 0:00 ` Robert Dewar
1999-08-11 0:00 ` Dmitry A. Kazakov
1999-08-11 0:00 ` Robert Dewar
1999-08-12 0:00 ` Dmitry A. Kazakov
1999-08-14 0:00 ` Robert Dewar
1999-08-16 0:00 ` Dmitry A. Kazakov
1999-08-11 0:00 ` Richard D Riehle
1999-08-05 0:00 ` Robert Dewar
1999-08-05 0:00 ` adam
1999-08-05 0:00 ` Robert Dewar
1999-08-05 0:00 ` What is a Display ? (was: Subverting 'Access for Sub-programs) Larry Kilgallen
1999-08-05 0:00 ` Hyman Rosen
1999-08-06 0:00 ` Robert Dewar
1999-08-06 0:00 ` Robert Dewar
1999-08-05 0:00 ` Subverting 'Access for Sub-programs adam
1999-08-06 0:00 ` Robert A Duff
1999-08-06 0:00 ` adam
1999-08-09 0:00 ` Robert A Duff
1999-08-09 0:00 ` Mark Biggar
1999-08-06 0:00 ` Brian Rogoff
1999-08-07 0:00 ` Gautier
1999-08-05 0:00 ` Robert A Duff
1999-08-05 0:00 ` Robert Dewar
1999-08-05 0:00 ` Brian Rogoff
1999-08-05 0:00 ` Steve Quinlan
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