On Wed, May 24, 2017 at 05:22:43PM +0200, Jan Pokorný wrote: > On 24/05/17 09:58 -0500, Jorge Gallegos wrote: > > On Wed, May 24, 2017 at 04:19:05PM +0200, Jan Pokorný wrote: > >> today, I've accidentally attested there are no stability guarantees > >> with the on-demand archives from common git hosting sites when preparing > >> a new pacemaker update, redownloading "spectool -s 0 pacemaker.spec" > >> of the original (-0.1.rc1, from 2 weeks ago) spec and comparing the > > > > Are you pointing to a _tag_ (or as github likes to call them: release) ? > > As far as I know tags can be re-created, isn't that what is happening > > here? > > Nope, the point is that nothing has changed in the codebase or, for > that matter, tags. It must have been GitHub that changed how its > equivalent of "git archive" behaves. > > >> hashes, which (surprisingly to me) didn't match (they were at any similar > >> test in the past). Then 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) > >>> > >>> -BUILD_VERSION=0459f40 > >>> +BUILD_VERSION=0459f40958 > >>> if test != ":%h$"; then > >>> AC_MSG_RESULT(archive hash: ) > >> > >> for configure.ac that indeed has export-subst git attribute set > >> and the change itself arises from "$Format:%h$" substitution. > >> This likely means GitHub was internally updated to use equivalent > >> of git 2.11 feature of abbreviation length autoscaling within > >> last 14 days. > > > > This is the other bit that makes me think it was actually the > > maintainers hand that moved this, I don't believe github does anything > > special to the code once it's stored there. There is no way for github > > to alter code afaik? > > Once more, see "git help archive", ATTRIBUTES section, export-subst > in particular. That exactly stands for the varying part, which is > implementation-specific, and GH implementation has apparently changed, > leading to changed contents of numerous archives to be downloaded from > that very point. Well, the title of your mail implies that *any* archive changed. What changed in fact is an archive with %h subst. But %h is inherently unstable: when commits are added to the archive, git will extend the generated abbreviation length to maintain uniqueness. I think the error here is in relying on stability %h substitution over time. Zbyszek _______________________________________________ devel mailing list -- devel@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to devel-leave@xxxxxxxxxxxxxxxxxxxxxxx
