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From: Robert A Duff <bobduff@shell01.TheWorld.com>
Newsgroups: comp.lang.ada
Subject: Re: Does GNAT support a thread-free RTS?
Date: Mon, 12 Sep 2011 09:01:17 -0400
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Date: 2011-09-12T09:01:17-04:00
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Ludovic Brenta <ludovic@ludovic-brenta.org> writes:

> - sjlj aka setjump/longjump, which is the alternative, in which every
> frame
>   that might possibly raise an exception calls setjmp(3), thus
                        ^^^^^

You meant "handle".

> incurring
>   distributed cost, and raising an exception calls longjmp(3), which
> is
>   cheap compared to the raising of an exception with ZCX.  sjlj is the
> only
>   supported run-time system on a few, non-mainstream architectures.

Right.  ZCX is the "right" way to implement exception handling,
because raising exceptions is rare, whereas exception handlers
(and finalizable objects) are not-so-rare, so you want to pay the
cost on the raise.

- Bob