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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:

mine	glibc
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?

Jerry


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