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From: Robert A Duff <bobduff@shell01.TheWorld.com>
Newsgroups: comp.lang.ada
Subject: Re: Delayed deallocation of non-terminated task in Gnat?
Date: Wed, 31 Aug 2011 14:08:26 -0400
Organization: The World Public Access UNIX, Brookline, MA
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Marc C <mc.provisional@gmail.com> writes:

> This *looks* to me like one could dynamically allocate a task instance
> and then immediately free it with an instantiation of
> Unchecked_Deallocation, yet the task would continue to function
> normally until it terminates.

Yes.  Ada semantics requires that if you call Unchecked_Deallocation
on an object that contains running tasks, the tasks keep running.

In the old version of GNAT, U_D would say "Is the task terminated?
If so, free up its resources.  If not, do nothing."  So it could
leak memory.

The new version of GNAT is better: "Is the task terminated?
If so, free up its resources.  If not, cause its resources
to be freed up when it does terminate."

But you have to be careful:  Like any U_D, you can have
dangling pointers.

- Bob