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RE: what if "languages" don't respond to 754R ?
Nick,
With regards to:
That is comparable with saying that you can't see
how to make a faster-than-light spaceship get into
a black hole and out again.
I don't even understand how to make a slower-than-light
spaceship with sufficient fuel to reach a black home.
Maybe that's the difference between a scientist and an
engineer(:>)?
Cheers,
DVJ
-----Original Message-----
From: stds-754@xxxxxxxx [mailto:stds-754@xxxxxxxx]On Behalf Of Nick
Maclaren
Sent: Friday, July 13, 2007 4:48 AM
To: stds-754@xxxxxxxx
Subject: Re: what if "languages" don't respond to 754R ?
Jason Riedy <ejr@xxxxxxxxxxxxxxx> wrote:
I personally would be happy to leave out (or make "should") the
widenTo stuff if we retained a requirement that each language
define a reproducible expression evaluation mode - [...]
"Mode" is not the right word. It will be confused with rounding
modes, etc. I'm well aware that you'd prefer all uses of modes
to become static, but that's a separate topic. I can't think of
a sane way to implement a dynamic "reproducible evaluation mode"
without extreme limitations on the rest of the runtime system.
That is comparable with saying that you can't see how to make
a faster-than-light spaceship get into a black hole and out again.
Until and unless we have some evidence that reproducible results
are even SPECIFIABLE in most important languages, worrying about
how they are requested is an irrelevance.
And I am stating that such evidence will not be forthcoming,
because the problem is intractable for several essential languages
(e.g. Fortran and C++) and insoluble for at least two essential
parallel paradigms (OpenMP or POSIX threads).
Regards,
Nick Maclaren,
University of Cambridge Computing Service,
New Museums Site, Pembroke Street, Cambridge CB2 3QH, England.
Email: nmm1@xxxxxxxxx
Tel.: +44 1223 334761 Fax: +44 1223 334679