Devel is broken, we cannot release

[Curtis Hovey-Canonical]

Devel has been broken for weeks because of regressions. We cannot
release devel. The stable 1.20.0 that we release is actually older
than it appears because we had to search CI for an older revision that
worked.

We have a systemic problem: once a regression is introduced, it blocks
the release for weeks, and we build on top of the regression. We often
see many regressions.The regression mutate as people merge more
branches.

The current two regressions are:
* win juju client still broken with unknown
  from  2014-06-27 which has varied as a compilation
  problem or panic during execution.
  https://bugs.launchpad.net/juju-core/+bug/1335328

* FAIL: managedstorage_test trusty ppc64
  from 2014-06-30 which had a secondary bug that broke compilation.
  https://bugs.launchpad.net/juju-core/+bug/1336089

I think the problem is engineers are focused on there feature. They
don't see the fallout from their changes. They may hope the fix will
arrive soon, and that maybe someone else will fix it.

I propose a change in policy. When a there is a regression in CI, no
new branches can be merged except those that link to the blocking bug.
This will encourage engineers to fix the regression. One way to fix
the regression is to identify and revert the commit that broken CI.


-- 
Curtis Hovey
Canonical Cloud Development and Operations
http://launchpad.net/~sinzui