Re: [PATCH OSSTEST] ap-fetch-version-old: Fix qemu branch handling after mergin of qemu trees

[Ian Campbell <ian.campbell@citrix.com>]

On Fri, 2015-10-23 at 11:23 +0100, Ian Jackson wrote:
> Ian Campbell writes ("[PATCH OSSTEST] ap-fetch-version-old: Fix qemu
> branch handling after mergin of qemu trees"):
> > ap-fetch-version-old should always reference the output gate, but
> > 99e92a6b3991 "Switch to merged qemu-xen{,-traditional}.git trees"
> > switched it to use TREE_QEMU_UPSTREAM directly, which can be
> > overridden by cr-daily-branch. This broke at least when
> > OSSTEST_BASELINES_ONLY=y since "cr-daily-branch qemu-mainline" ends up
> > looking
> > for an "upstream-tested" branch in the qemu.org git tree, when it
> > should be
> > looking at our output tree on xenbits.

You mentioned IRL that this also broke any cr-daily-branch which happened
to want to do a baseline test on qemu-mainline. Since we never force push
that tree it's unlikely this would have bitten us (just mentioning for
completeness since it hasn't occurred to me).

> > Follow pattern of TREE_LINUX and set BASE_TREE_QEMU_UPSTREAM to the
> > output gate and then conditionally set TREE_QEMU_UPSTREAM to the
> > BASE_TREE if it is not already set. Switch ap-fetch-version-old to use
> > BASE_TREE.
> ...
> > +if [ "x${TREE_QEMU_UPSTREAM}" ]; then
> > +	: ${TREE_QEMU_UPSTREAM:=${BASE_TREE_QEMU_UPSTREAM}}
> > +fi
> 
> ${FOO:=BAR} sets FOO iff FOO is unset or empty, so there is no need
> for the if.  The place you cribbed this from also has to set a
> variable for the refname.
> 
> Everthing else about this is fine.  Thanks for the in-person explanation.

As discussed IRC I dropped the if/fi (and retested) and have force pushed
to both the colo and the Cambridge instance.

I have removed the stop file from Cambridge.

Ian.