[oe] [OE-core] Use of github /archive/ tarballs in SRC_URI

[Burton, Ross]

On 19 September 2017 at 15:34, Carlos Alberto Lopez Perez <clopez at igalia.com
> wrote:

> On 19/09/17 10:09, Burton, Ross wrote:
> > Then the tarball for one of Erlang's repositories changed, and was
> noticed
> > by the checksum in the recipe (thanks Gunnar Andersson for reporting
> > this).  The extracted contents are identical, but the tarball itself has
> > changed.  I'm presuming this is due to the old tarball expiring in their
> > cache, and a newly generated tarball using a later version of tar.
>
> I don't think tar is the one to blame, but gzip.
> I have just tested GNU tar (versions 1.29 and 1.26) and BSD tar (from
> OpenBSD 5.8) and the 3 have produced identical archives (same md5sum)
> when invoked like git archive does.
>
> However, the .tar.gz file generated was different in the case of BSD.
> It even had a different file size.
>
> I bet that if you uncompress both files, the .tar will have the same
> checksum in both cases.
>

In the situation that I was talking to Gunnar with, the source is the tar
itself.

https://paste.fedoraproject.org/paste/rP67aSPn1IuYbQcz2UNY3g

They have identical length
> $ wc -c new-OTP-18.2.3.tar
> 159068160 new-OTP-18.2.3.tar
> 159068160 orig-OTP-18.2.3.tar
> ...but different content
> $ cmp new-OTP-18.2.3.tar orig-OTP-18.2.3.tar
> $ new-OTP-18.2.3.tar orig-OTP-18.2.3.tar differ: byte 79122433, line
> 2004431
>

Basically, both tar and gzip can cause problems.

Ross