Re: Access parameters and accessibility

[sbelmont700@gmail.com]

On Wednesday, December 17, 2014 9:30:57 AM UTC-5, Michael B. wrote:
> 
> If I understand you correctly this is not a compiler bug and this 
> optional rule was just not implemented in Gnat, right?
> 

It sounds very much like a compiler bug; regardless of the mechanism that the compiler writer chooses to use to implement the rules of the language, it must in fact implement them correctly and completely (i.e. all those conversions should pass, no matter if they use the model proposed in the paper, or something else entirely).  GNAT is infamous for blowing all sorts of dynamic accessibility checks, many much more common than this convoluted edge case, so it's not altogether shocking.  But as others have said, the rules are getting so insane that its tough to even know what the correct behavior ought to be, let alone whether a compiler does it (or could ever actually hope to do it at all).

Hopefully someone who knows more will verify what that code should actually do.

-sb