[fedora-virt] virt-preview on F16 fails due to yajl incompatibility

[Justin M. Forbes]

On Mon, 2011-11-14 at 09:21 -0700, Eric Blake wrote:
> On 11/14/2011 09:17 AM, Justin M. Forbes wrote:
> > On Mon, 2011-11-14 at 08:27 -0700, Eric Blake wrote:
> >> libreoffice on F16 requires yajl 1.0, but virt-preview built libvirt
> >> against yajl 2.0.  This means that it is not possible to use
> >> virt-preview on an F16 machine with libreoffice installed:
> >>
> >> --> Finished Dependency Resolution
> >> Error: Package: raptor2-2.0.4-2.fc16.x86_64 (@anaconda-0)
> >>            Requires: libyajl.so.1()(64bit)
> >>            Removing: yajl-1.0.12-1.fc16.x86_64 (@anaconda-0)
> >>                libyajl.so.1()(64bit)
> >>            Updated By: yajl-2.0.1-1.fc16.x86_64 (fedora-virt-preview)
> >>                Not found
> >>
> >> It looks like we need to back out the yajl changes from virt-preview,
> >> and rebuild libvirt to not require the newer yajl libraries.
> > 
> > Thanks, I did some checking to see if anything on my system required
> > yajl before I built it, but I don't have libre installed on that
> > machine.  I am kind of questioning what to do here, if we revert the
> > yajl requirement in libvirt, what are we missing, it certainly isn't a
> > full virt-preview.  On the other hand, if we tell people they can only
> > test on systems without Libre installed, we are going to have fewer
> > testers.  I suppose the other option is to add libreoffice from F17 to
> > virt-preview (ouch).  What do people think?
> 
> Libvirt should compile just fine with either yajl 1.0 or yajl 2.0 - that
> is, libvirt does not rely on any new features added in yajl 2.0, and the
> new yajl soname in rawhide is not a necessity for virt-preview (contrast
> that to other packages, such as where using an older sanlock-devel is
> problematic, and libvirt really does need sanlock-devel >= 1.8).
> 
> I think it's better to drop yajl from virt-preview, then rebuild libvirt
> against the yajl 1.0 library already present in F16, than it is to
> recompile libreoffice and anything else that is still stuck on the older
> yajl soname in F16.
> 
Probably a silly question, but if it does not require features from yajl
2.0, then why does the spec have:

BuildRequires: yajl-devel >= 2.0.1

Can we drop the versioning there if there is no real version
requirement?

Justin