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Newsgroups: comp.lang.ada
Date: Tue, 22 Mar 2016 16:17:53 -0700 (PDT)
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Subject: Re: Assignment with Adjust and Task Safety
From: rieachus@comcast.net
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Xref: news.eternal-september.org comp.lang.ada:29850
Date: 2016-03-22T16:17:53-07:00
List-Id: <comp.lang.ada>

On Tuesday, March 22, 2016 at 10:37:07 AM UTC-4, Jeremiah wrote:
=20
> Note that I am not accounting for the temporary objects for brevity in th=
e example.  Additionally, this may just be bad design all around, but I am =
trying to look at the mechanics behind this as well and if it is even possi=
ble to do this safely.

Very bad juju.  It is reasonable to write (Ada) code that has an access val=
ue declared constant, even if it is in a nested scope and changes value eve=
ry time the scope enclosing the variable is called.  Having multiple tasks =
assigning to the same (global) variable is usually wrong, and as Randy poin=
ted out, is very difficult to prove correct, even if it is...  Having a rul=
e that any variable set by more than one task will be protected saves you w=
eeks of debugging.