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From: Reto Buerki <reet@codelabs.ch>
Newsgroups: comp.lang.ada
Subject: Re: Barrier re-evaluation issue with GNAT 4.3.2
Date: Mon, 28 Sep 2009 12:28:52 +0200
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Date: 2009-09-28T12:28:52+02:00
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John B. Matthews wrote:
> I get the same result with FSF GNAT 4.3.4. I revised your code to follow 
> the "protected Event" example seen here:
> 
> <http://www.adaic.com/standards/95rat/RAThtml/rat95-p1-2.html#9>
> 
> It seems to work. The compiler warns, "potentially blocking operation in 
> protected operation" in Wakeup, although the Signal barrier is always 
> true. I'm not sure the extra entries _should_ be required, but I think 
> it might be more reliable in the face of multiple threads calling Wait. 
> I don't know a reason why it wouldn't work under 4.3.2.

Thanks for your effort in confirming the issue with GNAT 4.3.4 and for
the "protected Event" example.

We will see how we can integrate your idea into our project as a
workaround for the re-evaluation problem.