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Re: [v3] FP printing, take 2
Paolo Carlini writes:
> Jerry Quinn wrote:
> >Final comments?
> Hi Jerry, two quick comments.
> I wanted to ask how are you testing the ongoing work: I remember you had
> a script comparing printf to the inserters and that we still had some
> minor problems (proably false alarms) in corner cases... I would be
> happy to run something similar on a few 64-bit architectures but maybe I
> will not be really able to do that during the next 1 & half week or so.
> Let's keep in touch.
I still use the same program. It had the core code being called directly and
compared the results to sprintf. I run about half a million random or regular
numbers through looking for differences. The only ones I see are:
0.0001 1e-04 %g style
1e00 1e-00 %e style
In both cases I think glibc is wrong, based on printf docs around the web. I
don't have the C standard, so I can't confirm, though.
I'd be happy to send you the test prog for 64 bits. I need to pull it off the
machine it's sitting on.
I also have another program I extracted from the old libio code testsuite. It
tests things in slightly different ways.
> Another unrelated comment: are you taking into account in the design
> that bug with grouping & zero precision (no decimal point, anyway) that
> I mentioned some time ago? Basically, we look for the decimal point and
> we group everything to its left: if we don't find it, we group also the
> exponential part, if present! Fixing it in the current framework its
> feasible but very ugly, and I was wondering whether we can arrange for
> the new framework to make it easier...
I remember there being an issue, but I haven't paid attention to it in this
work. I'll think about whether this stuff makes it any easier. I'm not sure
it does. What's the PR?