On 03/03/2018 01:34 PM, Kevin Kofler wrote:
That is due to the "Rawhide can never go backwards" policy,
which I still do
not understand the point of, especially in the light of "distro-sync" having
been supported by both the old yum and the new dnf for years.
Sometimes an updated package makes changes to its data structures. For
example, consider if the package does some kind of migration to its data
in such a way that the new version can read it, but the old cannot (e.g.
a PostgreSQL upgrade, and IIRC the Firefox discussion from a while ago
also noted that it cannot be downgraded in all cases). Thus, distro-sync
doesn't work in all cases if the upgraded package has already made
changes on the user's system.