preventing md5 mismatch errors from compression changes

[Andre Robatino]

Andre Robatino <robatino <at> fedoraproject.org> writes:

> 2) is easy enough. To get F14 to use the new compression unconditionally, I
> downloaded the Rawhide version of several packages and then used yum shell with
> the commands
> 
> config gpgcheck 0
> install xz-compat-libs-5.0.0-4.fc15.x86_64.rpm
> update xz-5.0.0-4.fc15.x86_64.rpm xz-libs-5.0.0-4.fc15.x86_64.rpm
> deltarpm-3.6-0.4.20100708git.fc15.x86_64.rpm
> deltaiso-3.6-0.4.20100708git.fc15.x86_64.rpm
> python-deltarpm-3.6-0.4.20100708git.fc15.x86_64.rpm
> run
> 
> and to reverse the process (necessary so yum-presto will work), yum shell again
> with the commands
> 
> remove xz-compat-libs
> downgrade xz xz-libs deltarpm deltaiso python-deltarpm
> run
> 
> The old and new versions of deltarpm use the old and new compression
> unconditionally, resp.

I'm wondering why the new xz isn't pushed to F14 and below. With xz-compat-libs
providing liblzma.so.0, yum-presto works normally. It's only if
deltarpm/deltaiso are updated to the F15/Rawhide versions that it breaks. Would
anything else break - other than the fact that command-line xz would compress
differently?