On Thu, Jan 3, 2013 at 3:29 PM, Jack O'Quin wrote: > On Thu, Jan 3, 2013 at 2:54 PM, Brian Gerkey > wrote: >> >> hi Vijay, >> >> Thanks for the reply, and don't feel bad. It didn't cause us that >> much pain (thanks to Hugo's quick thinking as to the cause). >> >> Also, to be honest, I wasn't aware that REP 9 is in effect. I recall >> Josh writing it ages ago, but didn't know that we'd adopted it as a >> policy. So I wouldn't have thought twice about introducing >> ABI-breaking changes myself. >> >> Of course, REP 9 is a good policy and we should all be following it. >> It probably hasn't come up much in the past because if you only >> release your code using the ROS release system, then your debs will >> all be strictly version-locked and you won't see this problem. But >> now, people (like us) are starting to release stuff in other ways >> while depending on ROS debs. That's a good thing, and is something >> that we should work to support. > > > My understanding of REP 9 is that ABI consistency is only required *within* > an even-cycle release, such as Fuerte or Groovy. Not *between* releases. > > Is that what we are talking about here? Yes: pr2_mechanism had an ABI-breaking change somewhere between 1.6.1 and 1.6.4, all of which were released into Fuerte. brian.