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From: Randy Brukardt on 10 Oct 2009 01:41
"Jeffrey R. Carter" <spam.jrcarter.not(a)spam.acm.org> wrote in message
news:h9rco8$u58$1(a)news.tornevall.net...
> Robert A Duff wrote:
>>
>> Pragma Detect_Blocking will cause GNAT to raise Program_Error.
>> If you want to write portable code, you should use this
>> pragma.
>
> I thought there would be a way to make GNAT be an Ada compiler, but a
> quick look at the secret documentation didn't find it.

GNAT does some weird things, but this isn't one of them. Pragma
Detect_Blocking is standard Ada 2005 (added for the Ravenscar profile). It
should be the default, but it isn't because various real-time people who
ought to know better don't want to pay the miniscule cost of the check. [I
think the check should be the default with the possibility of check
suppression -- which hardly ever would be used. But some people think
possible deadlocks are a better outcome. Bah!] Because of that, almost all
Ada compilers will behave as GNAT does in this case. If you want portable
Ada code (at runtime), you need to include the pragma -- for *all*
compilers, not just GNAT. (If you are doing pure Ada 95, you are out of
luck, unfortunately.)

Randy.


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