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From: Robert A Duff <bobduff@shell01.TheWorld.com>
Newsgroups: comp.lang.ada
Subject: Re: Language lawyer question: task activation
Date: Thu, 19 Feb 2009 18:54:50 -0500
Organization: The World Public Access UNIX, Brookline, MA
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Date: 2009-02-19T18:54:50-05:00
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Adam Beneschan <adam@irvine.com> writes:

> Should this program deadlock?  I don't think it should (and I think it
> should display "E1 accepted"), based on my understanding about when
> task activation is supposed to occur for the function result.

I think you're right.  The task should be activated after Func returns,
before calling Do_It.

>...But
> perhaps there's something about the relation between task activation
> and masters that I don't understand.  Anyway, this hangs when I
> compile it with GNAT and run it---is this correct or not?
>
>                                         -- thanks, Adam
>
> with Text_IO;
> procedure Test is
>
>     task type TType is
>         entry E1;
>     end TType;
>
>     task body TType is
>     begin
>          accept E1 do
>             Text_IO.Put_Line ("E1 accepted");
>          end E1;
>     end TType;
>
>     function Func return TType is
>     begin
>         return X : TType;
>     end Func;
>
>     procedure Do_It (X : TType) is
>     begin
>         X.E1;
>     end Do_It;
>
> begin
>     Do_It (Func);
> end Test;

- Bob