On Thursday, February 03, 2011 03:56:00 pm Barry Warsaw wrote: > I've tried to send this to the list several times, but it hasn't gone > through. I received no responses, but now at least I'm glad to know that > it wasn't y'all ignoring me, just lists.ubuntu.com. ;) Let's see if I've > cleared up my mail issues... > > Rather than resend, I'll just summarize the current state as I know it. > > Over the last couple of weeks, I did some analysis on the archive, looking > for packages that depend on Python, but didn't include Python 2.7 support. > I wrote some scripts at lp:~barry/+junk/pydeps and specifically the > deps2.py script. > > While the script isn't perfect, I think it's good enough to determine where > we are with main. The script produces a few false positives, but from > spot checking the output, I found no false negatives. The summary is that > right now, I know of no packages in Natty main that explicitly depend on a > Python < 2.7. There are a few that depend on > Python 2.6; that's not > ideal, but I think it's fine, and possibly moot (see below). > > (The first time I tried to send this message on 2011-01-24, there were a > few packages that were broken but AFAIK, all have been fixed now.) > > I have not done a similar analysis on universe. > > This is just the first level of Python 2.7 support analysis. The next test > I ran was to actually install in a Natty VM all main packages that depend > on Python, looking for failures-to-install. A recent example was bug > 685476 on mgltools-viewerframework. This included an assignment to > __debug__ as an attribute of an object, which is not allowed in Python 2.7 > (it wasn't strictly legal in 2.6 either, but the interpreter did not > prevent it until 2.7). These are the kinds of bugs you can only find when > you install the package because they only show up when the modules are > byte-compiled. > > Since my first attempt at emailing this summary, I've fixed a number of > packages that had these kinds of install-time failure. Examples included > kubuntu-full, python-avogadro, python-qscintilla2, and python-vigra (since > demoted by Colin). As of today, all have been fixed and are now > installable. > > It's still possible that packages have incompatibilities with Python 2.7, > but you can only find them when you use the code, and that's not something > I can reasonably test. So, if you encounter bugs related to Python 2.7 > support, please file them as usual against the offending package, and add > the official 'python27' tag to the bug. > > So now that Natty main support for Python 2.7 looks pretty good, the > question is: do we drop Python 2.6 from Natty? > > Pro-removal: > > * It reduces the CD space requirements by including only one shared > library per extension module. I forget exactly how much can be reclaimed, > though IIRC doko posted some numbers on that (10MB or thereabouts?). > * Makes our life simpler by only having to support one Python 2 version > from here on out, and that being the one supported by upstream Python long > term. > > Con-removal:
I understand why Canonical cares about Launchpad and how easily it can be upgraded to 12.04 when the time comes. They solved this with a PPA for upgrade to 10.04 and I think that's a sufficient solution. I don't think we need to concern ourselves with it. The much bigger con is that we don't know how well Python 2.7 is really going to work. - The package update analysis for Universe/Multiverse is incomplete at best. - Even if packages build, we don't know what runtime issues they will have until users have used them a bit. - Debian has not even started to transition to 2.7 (except a very limited number of packages in experimental) and so we don't have the benefit of their work on the transition. The major benefit associated with removal is getting a little CD space back. Since all the ISOs are down to where they fit without this, I think we shouldn't worry about it so much for this cycle. I'm all for dropping it early (like during the toolchain phase) of Natty +1, but I don't see much in the way of benefit with removal now while I do see significant risks. Scott K -- ubuntu-devel mailing list [email protected] Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-devel
