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Re: RFC: Separate commit identification from Merkle hashing

From
Jonathan Nieder <jrnieder@gmail.com>
Date
May 23, 2019, 20:54 UTC
Message-ID
<20190523205457.GC70860@google.com>
In-Reply-To
<20190523205009.GA69096@thyrsus.com>
Eric S. Raymond wrote:
> Jakub Narebski <jnareb@gmail.com>:
Show 7 quoted lines
>> Currently Git makes use of the fact that SHA-1 and SHA-256 identifiers
>> are of different lengths to distinguish them (see section "Meaning of
>> signatures") in Documentation/technical/hash-function-transition.txt
>
> That's the obvious hack.  As a future-proofing issue, though, I think
> it would be unwise to count on all future hashes being of distinguishable
> lengths.

We're not counting on that. As discussed in that section, future hashes can change the format.

[...]
>> All right.  Looks sensible on first glance.
>
> I am very relieved to hear that. My view of git is outside-in; I was quite
> worried I might have missed some crucial issue.

Honestly, I do think you have missed some fundamental issues. https://public-inbox.org/git/ab3222ab-9121-9534-1472-fac790bf08a4@gmail.com/ discusses this further.

Regards, Jonathan

Previous: Eric S. RaymondNext: Eric S. Raymond
Message 10 of 13 in “RFC: Separate commit identification from Merkle hashing”
  1. Eric S. RaymondMay 21, 2019
  2. Jonathan NiederMay 21, 2019
  3. Eric S. RaymondMay 21, 2019
  4. Jonathan NiederMay 21, 2019
  5. Eric S. RaymondMay 21, 2019
  6. Jakub NarebskiMay 23, 2019
  7. Jonathan NiederMay 23, 2019
  8. Eric S. RaymondMay 23, 2019
  9. Eric S. RaymondMay 23, 2019
  10. Jonathan NiederMay 23, 2019
  11. Eric S. RaymondMay 23, 2019
  12. Randall S. BeckerMay 23, 2019
  13. Ævar Arnfjörð BjarmasonMay 23, 2019

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