Hi,

Since I'm now making commits on wip-ppc64le to add support for POWER9
machines like the Talos II and Blackbird from Raptor Computing Systems,
I'd like to understand more about how I am expected to manage that
branch.  Before I touched it, it sat with just one lonely commit,
essentially unused.  So it seems to me like I'm not stepping on anyone's
toes, and that I should just make commits like I normally would on
master, staging, or core-updates, being careful to follow the usual
guidelines.

Specifically, I'm curious to know:

- Is it usually expected that wip branches can be rebased?  I don't plan
  to rebase wip-ppc64le, since I'd like to be able to coordinate with
  others using this branch, but I'm not sure what others expect.

- Should I just periodically merge from master, or perhaps core-updates,
  to keep wip-ppc64le up to date and resolve conflicts early?  I've
  already merged master into this branch once, to get it back up to
  date.  I haven't merged core-updates into it yet.  I think
  periodically merging branches into wip-ppc64le is the right thing to
  do, since eventually the end goal will be to merge wip-ppc64le into
  core-updates to get POWER9 support into a release.  However, I suppose
  if I merge from different branches, I could wind up dealing with
  unnecessary conflicts.

- For Efraim specifically, there is some overlap between the work
  required on wip-ppc64le and the work required on wip-ppc.  I have
  already cherry-picked one of your commits
  (2da8fcfdee7cfde8110a68806f3c4d497f217fe5) onto wip-ppc64le (as commit
  52f0b3db6ef3d3c5067c704c2190f72d2994a999), since it was needed.  How
  would you like to coordinate this work?

- Are there any other tips/advice/rules?

Thank you,

-- 
Chris