From: "Adam Beneschan" <adam@irvine.com>
Subject: Re: To collection (GNAT bug)
Date: 4 Oct 2006 10:18:47 -0700
Date: 2006-10-04T10:18:47-07:00 [thread overview]
Message-ID: <1159982327.758504.26940@i42g2000cwa.googlegroups.com> (raw)
In-Reply-To: u0sk26qjz46b$.1v1mgzx5feup8$.dlg@40tude.net
Dmitry A. Kazakov wrote:
> On Mon, 02 Oct 2006 09:06:42 -0400, Frank J. Lhota wrote:
>
> > Dmitry A. Kazakov wrote:
> >> On Sun, 01 Oct 2006 19:23:26 GMT, Jeffrey R. Carter wrote:
> >> However, I don't think that it was really the intended behavior in this
> >> case. [ If access String is a fat pointer, then Unchecked_Conversion should
> >> not be allowed at all. Otherwise it must honor the String's dope. ]
> >
> > I would agree that an unchecked conversion between an address and a fat
> > pointer (or any two types of different sizes, for that matter) should at
> > least trigger a warning.
>
> Well, actually, it gives a warning, that sizes are different.
Ummm, wait a minute. If the sizes are different, why did you think
that the Unchecked_Conversion would be reversible? I tried your
example on GNAT (Linux/x86), and it told me that X'Size=64 and
Addr'Size=32. When you convert the 64-bit type to the 32-bit type, of
course you will lose some information that you won't recover when you
get it back. It's mathematically impossible for this to be reversible.
-- Adam
next prev parent reply other threads:[~2006-10-04 17:18 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-09-30 19:46 To collection (GNAT bug) Dmitry A. Kazakov
2006-10-01 1:21 ` Jeffrey R. Carter
2006-10-01 8:00 ` Dmitry A. Kazakov
2006-10-01 19:23 ` Jeffrey R. Carter
2006-10-01 22:33 ` Frank J. Lhota
2006-10-02 3:08 ` Jeffrey R. Carter
2006-10-02 13:02 ` Frank J. Lhota
2006-10-02 19:50 ` Jeffrey R. Carter
2006-10-02 8:23 ` Dmitry A. Kazakov
2006-10-02 13:06 ` Frank J. Lhota
2006-10-02 13:43 ` Dmitry A. Kazakov
2006-10-04 17:18 ` Adam Beneschan [this message]
2006-10-04 18:51 ` Dmitry A. Kazakov
2006-10-02 19:45 ` Jeffrey R. Carter
2006-10-03 8:36 ` Dmitry A. Kazakov
2006-10-03 19:10 ` Jeffrey R. Carter
2006-10-04 8:01 ` Dmitry A. Kazakov
2006-10-04 9:27 ` Georg Bauhaus
2006-10-04 12:10 ` Dmitry A. Kazakov
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