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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Subject: Re: Gem 39 - compiler specific?
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Date: Fri, 4 Sep 2009 09:29:07 +0200
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Date: 2009-09-04T09:29:07+02:00
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On Thu, 3 Sep 2009 17:06:48 -0500, Randy Brukardt wrote:

> The intent leads to the rule that Unchecked_Conversion is only well-defined 
> when the sizes of the two types are the same. As noted, that doesn't need to 
> be the case for System.Address.
> 
> You seem to want to muddle up the semantics to include some real 
> conversions.

Do we need that semantics (reinterpret bit pattern as another type)? It is
difficult to invent a case where an access value would be obtained from a
bit patterns. It is never needed, IMO.

> That would be a problem inside of generics (what if the actual 
> parameter is System.Address??

OK. (However there are already similar cases with generics)

> Do you get the special semantics or not? 
> Either answer is uncomfortable and requiring the special semantics would 
> have bad consequences on code generation and legality rules), and in any 
> case is not very consistent.

Yes.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de