Re: Motion 4
Dear John,
I find the terms of this motion quite confusing. Did you mean "P1788 compliance
implies IEEE 754-2008 compliance"?
Also, the terms "architectures" is maybe too specific. What about a hardware
that is IEEE 754-2008 compliant, but an environment on top of it (compiler
and/or operating system) that is not IEEE 754-2008 compliant?
I would thus have said "An environment that is not IEEE 754-2008 compliant
is not P1788 compliant".
Paul Zimmermann
> From: John Pryce <j.d.pryce@xxxxxxxxxxxx>
> Date: Thu, 9 Apr 2009 08:28:19 +0100
>
> <<Sorry, forgot to adjust the title of the motion!. Try this.>>
>
> Dear members of the working group.
> I propose the following motion.
> John Pryce
>
>
> ===Motion P1788/M0004.01_Keep_to_754===
> Proposer: John Pryce
> Seconder: Dan Zuras
>
> ===Motion text===
> P1788 says nothing about interval arithmetic on computer
> architectures that
> are not 754-compliant.
>
> ===Rationale===
> This motion is in support of KISS: "Keep It Simple, Stupid". It
> delimits 1788's responsibilities. It limits and simplifies our work
> in that our design decisions may freely assume the existence of NaN
> (and possible payload), the sign-exponent-significand layout, etc.
>
> The question has been asked: If 1788 says nothing about non-754
> architectures, does that mean that any interval implementation on
> such an architecture is automatically 1788-compliant?
>
> This IMO is not a question about the motion but about what standard-
> compliance means. My understanding is that
> an implementation is compliant with a standard iff it obeys every
> normative clause in that standard.
>
> Therefore it is *conceivable* that an implementation on a non-754
> machine can be made 1788-compliant -- in the unlikely case that 1788
> actually makes no 754-specific decisions!
>
> In practice, presumably, that will not be so. Then, someone may
> consider that 1788 should define a "lower tier" of compliance for
> intervals on non-754 machines. They may wish to move a suitable
> amendment to this motion.