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From: Robert A Duff <bobduff@shell01.TheWorld.com>
Newsgroups: comp.lang.ada
Subject: Re: Barrier re-evaluation issue with GNAT 4.3.2
Date: Mon, 28 Sep 2009 17:13:24 -0400
Organization: The World Public Access UNIX, Brookline, MA
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"Jeffrey R. Carter" <spam.jrcarter.not@spam.acm.org> writes:

> An entry call is always potentially blocking, regardless of its barrier;
> see ARM 9.5.1. Technically, this code contains a bounded error. Since
> the potentially blocking operation was detected, your program should
> raise Program_Error; GNAT pretends that it hasn't detected that the
> operation is potentially blocking and lets you get away with only a
> warning. Other compilers (and even other versions of GNAT) may actually
> raise Program_Error.

Pragma Detect_Blocking will cause GNAT to raise Program_Error.
If you want to write portable code, you should use this
pragma.

- Bob