From mboxrd@z Thu Jan  1 00:00:00 1970
From: Bill Zaumen <bill.zaumen@gmail.com>
Subject: Re: Suggestion on hashing
Date: Mon, 05 Dec 2011 22:02:27 -0800
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Cc: "Chris West (Faux)" <faux@goeswhere.com>,
	Jeff King <peff@peff.net>,
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To: Nguyen Thai Ngoc Duy <pclouds@gmail.com>
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On Tue, 2011-12-06 at 11:46 +0700, Nguyen Thai Ngoc Duy wrote:
> On Tue, Dec 6, 2011 at 8:56 AM, Chris West (Faux) <faux@goeswhere.com> wrote:
> >
> > Nguyen Thai Ngoc Duy wrote:
> >>
> >> SHA-1 charateristics (like 20 byte length) are hard coded everywhere
> >> in git, it'd be a big audit.
> >
> >
> > I was planning to look at this anyway.  My branch[1] allows
> >  init/add/commit with SHA-256, SHA-512 and all the SHA-3 candidates.
> 
> Great!

If you are replacing SHA-1 as an object ID with another hash function,
two things to watch are submodules and alternative object databases.
Because of those, it is necessary to worry about the order in which
repositories are converted.  In the worst case for submodules, you'd
have to do multiple repositories at the same time, switching between
them depending on what you need at each point.