Subject: Re: [boost] GGL Review
From: Phil Endecott (spam_from_boost_dev_at_[hidden])
Date: 2009-11-16 15:38:05
Hartmut Kaiser wrote:
>> Brandon Kohn wrote:
>> are many buggy floating point boolean op libraries out there. Why do we
>> need another?
> I would like to ask you to refrain from spreading FUD with regards to the
> library under review without any concrete proof.
Hartmut, I'm unhappy that you as review manager made that comment. You
ought to be more impartial. I don't think it's unreasonable to call
the FP robustness issues "bugs". I think it's very likely that GGL has
these issues when used with FP coordinates, and I don't accept your
"concrete proof" requirement for making that allegation. The library's
approach seems to be, "if you're not happy with undefined behaviour,
use an arbitrary-precision coordinate type". Please correct me if I'm
wrong, but I believe the library doesn't provide any way to hide the
arbitrary-precision type and the type conversions from the user as an
implementation detail, nor does it have a mechanism to fallback only
when it detects a problem with the FP calculation, nor have any
benchmarks been done on the arbitrary-precision case.