From: rsbecker@nexbridge.com
Date: Mon, 25 Jul 2022 22:35:30 GMT
Subject: RE: Can I use CRoaring library in Git?
Message-ID: <028201d8a076$dbb5a7d0$9320f770$@nexbridge.com>
In-Reply-To: <Yt8VzTLmVOKCALxr@nand.local>

On July 25, 2022 6:15 PM, Taylor Blau wrote:
>On Mon, Jul 18, 2022 at 08:18:14AM -0400, Derrick Stolee wrote:
>> On 7/18/22 7:48 AM, Abhradeep Chakraborty wrote:
>> > I just got to know that CRoaring doesn't support Big Endian systems
>> > (till now) -
>> >
>> > https://groups.google.com/g/roaring-bitmaps/c/CzLmIRnYlps
>> >
>> > What do you think about this?
>>
>> Git cares enough about compatibility that that might be a deal-breaker
>> for taking the code as-is. If we _did_ take it as-is, then we would
>> need to not make it available on such machines using compiler macros.
>
>I definitely agree here. If I'm understanding CRoaring's implementation correctly, a
>bitmap written on a machine that uses big endian would be unreadable on a little
>endian machine and vice-versa.
>
>That's definitely *not* the case with the existing EWAH bitmaps, which are
>readable on machines using either endianness, since we always write numbers in
>network byte order, independent of machine endinaness.
>
>(I suspect you know all of this already, but just stating here explicitly for the
>benefit of the list).

It is possible to use a Clean/Smudge filter to normalize the format to be independent of the endian-ness of the target platforms?

I have to admit being a fan of that approach.
--Randall