Jonas, I'm low on energy, so I'm not going to review this now, but I there are a few points I want to mention.
1. thanks for cleaning things up! 2. maybe the rounding change should wait for 2.21.1 3. please don't look at real.hh/cc; I've got a patch for it that I'm waiting to post https://codereview.appspot.com/553740043/
