Issue with git fetcher

[Gary Thomas <gary@mlbassoc.com>]

I like to run Poky/Yocto with a pre-populated source cache,
built up over time, and rely on BB_NO_NETWORK to tell me
when stuff actually needs to come from the network.  This
works quite well - only when there is a new/changed recipe
do I have to relax BB_NO_NETWORK and once I've built the
offending recipe, I save the sources (I also use BB_GENERATE_MIRROR_TARBALLS="1")
back to my source cache.

I ran across an issue with this with a recipe I imported from
meta-openembedded/meta-oe.  It contained these lines:
   SRCREV = "2fb4be9a99a2c2a9435339830e3d940171cc0d9b"
   SRC_URI = "git://git.libav.org/libav.git;protocol=git;branch=release/0.8"

So, the first time I built it without BB_NO_NETWORK, then I saved
the resulting tar file.  However, when I tried to build it again,
this time in a new build tree with BB_NO_NETWORK set, it failed!
I went looking through the tar file (just a bare clone of the git tree)
and found that the revision in question was not there.

The only thing I could see that's unique about this recipe is the
'branch=release/0.8'.  To see if this was the issue, I removed it
and replayed the whole process (rebuilding the tar file) & now fetch
works even with BB_NO_NETWORK :-)

Is this expected, or is it a bug?

n.b. I hammer on this functionality as I have to deliver fixed source
packages to customers (some of whom may not have easy network access,
some who just want to know what they are getting/using), so I rely
on being able to build with BB_NO_NETWORK set.

Thanks

-- 
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Gary Thomas                 |  Consulting for the
MLB Associates              |    Embedded world
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