Subject: Re: [PATCH 0/2] Re-integrate sha1dc

From: Junio C Hamano <[email-masked]>
Date: Thu, 16 Mar 2017 15:23:59 -0700

Jeff King <[email-masked]> writes:

> On Thu, Mar 16, 2017 at 06:04:56PM -0400, Jeff King wrote:
>
>> So here's my version. It's on top of the hash.h tweak, as well.
>> 
>>   [1/5]: add collision-detecting sha1 implementation
>>   [2/5]: sha1dc: adjust header includes for git
>>   [3/5]: sha1dc: disable safe_hash feature
>>   [4/5]: Makefile: add USE_SHA1DC knob
>>   [5/5]: t0013: add a basic sha1 collision detection test
>> [...]
>>  t/t0013/shattered-1.pdf |  Bin 0 -> 422435 bytes

A 420k binary blob has become ~500k base85 binary patch, which is
larger than 100k.

> So obviously I had the same 100K problem you did on the first patch, but
> the fifth one also won't make it to the list. You can pull the whole
> thing from:
>
>   https://github.com/peff/git.git jk/sha1dc

Thanks.  

For today's integration, I have the one from Linus only because it
came earlier and today's integration cycle was already running.  I
agree with this series that disables the safe-hash thing.

I am wondering if we should queue another one for .travis.yml on top
to force use of USE_SHA1DC=YesPlease during the tests.  I expect
that we'd be encouraging its use for ordinary users without any
specific needs in the release notes in 2.13 release.