Re: Revision 144098 (d.d. Wed Feb 11 08:56:41 2009 UTC (4 weeks ago)) is not a regression bug fix.

[Toon Moene <toon at moene dot org>]

Steven Bosscher wrote:

> On Wed, Mar 11, 2009 at 11:20 PM, Toon Moene <toon@moene.org> wrote:
> > I will abide by the rules - but the rules also say that this is not the sort
> > of "fix" that goes in at phase 4.
>
> Which rule where says so? Not intended in an offensive manner -- just
> curious. I'm not aware of any rules that specify what kind of
> regression can be fixed and how.  I thought the rule is "fix
> regressions", not "fix some regressions but not others".

The point is that people want a compiler to generate correct code.  So 
any regression that produces wrong code in some circumstances is, well, 
a regression.

Now, of course, it is possible that a change to the compiler might 
result in it generating slower code.  That is also a regression.

Then the challenge is to fix the optimization regression without 
introducing a correctness regression.

Because I bet most of our "customers" would prefer correct answers 
(within the accuracy that the problem at hand requires) over fast, but 
wrong answers (outside the accuracy that the problem at hand requires).

As you can see from the logs I pasted, there are Infinity's and there 
are finite answers.

I can assure you that we, in meteorology, prefer finite answers, because 
they correspond with the real world we observe.

Hope this helps,

--
Toon Moene - e-mail: toon@moene.org (*NEW*) - phone: +31 346 214290
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