Re: Clause 10, Expression Evaluation

[David Hough 754R work <754r@xxxxxxxxxxx>]

> > At the higher levels one is often debugging the hardware,
> > operating system, compilers, and libraries,
>
> Well yes, but almost no-one does that.  (Those who think they spot  
> hardware,
> operating system, compiler or library bugs are usually wrong.)

But it's almost never economic to track down the blame, so a typical
course of action is to reduce the optimization level and blame the hardware
for not living up to its advertised performance.

The inherent non-reproducibility of floating-point arithmetic as it has 
been done historically has enabled all sorts of sins to be concealed,
and that's one of my motivations for pressing the issue as far as
it can be pressed in this revision.     At least if one requests 
reproducible results in appropriate circumstances and still gets varying
results, one knows that somebody else in the hardware-software chain is not
living up to his end of the bargain. 

Some of the opposition to a reproducible-results option might be attributable
to a fear of what bugs might be turned up that must be dealt with by vendors
rather than users, and perhaps also to fear that
(like decimal) it might become a popular paradigm over time, to which vendors
might be forced to submit by weight of benchmarks (while still being required
to provide peak performance as well).