From mboxrd@z Thu Jan  1 00:00:00 1970
From: ludo@gnu.org (Ludovic =?utf-8?Q?Court=C3=A8s?=)
Subject: Re: github tarballs problematic?
Date: Fri, 09 Jun 2017 15:53:25 +0200
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References: <20170608203528.rvp4lhdqu463ns2x@abyayala>
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In-Reply-To: <20170608203528.rvp4lhdqu463ns2x@abyayala> (ng0@pragmatique.xyz's
	message of "Thu, 8 Jun 2017 20:35:28 +0000")
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To: guix-devel@gnu.org

Hi ng0,

ng0 <ng0@pragmatique.xyz> skribis:

> I've just come across this post via https://pagure.io/pagure/issue/861
> https://lists.fedoraproject.org/archives/list/devel@lists.fedoraproject.o=
rg/message/UDZ2WKMTOE6J2M4K7PF5OWSSC4BAX2SH/
>
> quote in almost full:
>
> today, I've accidentally attested there are no stability guarantees with =
the on-demand archives from common git hosting sites when preparing a new p=
acemaker update, redownloading "spectool -s 0 pacemaker.spec" of the origin=
al (-0.1.rc1, from 2 weeks ago) spec and comparing the hashes, which (surpr=
isingly to me) didn't match (they were at any similar test in the past). Th=
en I looked at the adiff output:
> ...
>  diff -ru Unpack-2241/pacemaker-Pacemaker-1.1.17-rc1/configure.ac
> Unpack-6255/pacemaker-Pacemaker-1.1.17-rc1/configure.ac
>  --- Unpack-2241/pacemaker-Pacemaker-1.1.17-rc1/configure.ac2017-05-09 00=
:55:15.000000000
> +0200
>  +++ Unpack-6255/pacemaker-Pacemaker-1.1.17-rc1/configure.ac2017-05-09 00=
:55:15.000000000
> +0200
>  @@ -1159,7 +1159,7 @@
>   AC_PATH_PROGS(GIT, git false)
>   AC_MSG_CHECKING(build version)
>=20=20=20
>  -BUILD_VERSION=3D0459f40
>  +BUILD_VERSION=3D0459f40958
>   if test  !=3D ":%h$"; then
>      AC_MSG_RESULT(archive hash: )=20
> for configure.ac that indeed has export-subst git attribute set and the c=
hange itself arises from "$Format:%h$" substitution. This likely means GitH=
ub was internally updated to use equivalent of git 2.11 feature of abbrevia=
tion length autoscaling within last 14 days. Hope this will be useful for s=
ome (e.g. fedora-review tool has a check to redownload and diff sources aga=
inst SRPM content, IIRC).

Interesting.  IIUC this only affects projects that use this
=E2=80=9C$Format:%h$=E2=80=9D feature, right?  I wonder how widespread it i=
s.

Thanks for the heads-up,
Ludo=E2=80=99.