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Subject: Re: [PATCH v3] replace timeconst bc script with an sh script
To:     Ethan Sommer <e5ten.arch@gmail.com>
CC:     Jonathan Corbet <corbet@lwn.net>,
        Federico Vaga <federico.vaga@vaga.pv.it>,
        "Chang S. Bae" <chang.seok.bae@intel.com>,
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On November 3, 2019 1:56:50 PM PST, Ethan Sommer <e5ten=2Earch@gmail=2Ecom>=
 wrote:
>> Please let me point out, again, that bc *is* part of the basic POSIX
>toolset, and the only tool in that toolset that allows for
>arbitrary-precision arithmetic=2E That being said, GNU as, which we also
>depends on, also contains bigint arithmetic, so it might be possible to
>coax as into outputting ASCII output without manually implementing
>bigints manually=2E
>>
>> Another option would be to use a C program linked with gmp=2E Binutils
>requires gmp, so it doesn't inherently add dependencies, but running it
>though as would probably be easier at least for the LLVM guys=2E
>>
>> I also have written a small, portable C bigint library, but that is a
>lot of code to add to the tree=2E
>I don't know what the requirement is for the level of precision this
>would need to support is, so I don't know if this meets them, but I
>made
>a C program that doesn't use gmp, so while it probably doesn't
>theoretically have the same level of precision as bc, it does match it
>for output on anything up to 15000 (it doesn't stop matching
>timeconst=2Ebc above 15000 I just didn't test any higher)=2E The program =
is
>here: http://ix=2Eio/20Ka
>If this is considered precise enough to be an acceptable replacement
>I will make a new patch to use it in place of timeconst=2Ebc=2E

The point isn't to make it work *now*, but getting it to *stay* work=2E
--=20
Sent from my Android device with K-9 Mail=2E Please excuse my brevity=2E