[Python-Dev] Time for 2.3.3?

Tim Peters tim.one at comcast.net
Thu Nov 20 18:30:15 EST 2003


Over the last week, I checked in fixes for two distinct broad causes of
segfaults in code using weakrefs with callbacks.  The bugs have been there
since weakrefs were introduced, but for whatever reason nobody bumped into
them (knowingly) until Jim Fulton and Thomas Heller happened to provoke
both, independently, within a day of each other.  It was especially easy
under Thomas's scenario *not* to get a segfault in a release build, but to
suffer random memory corruption instead (if the double-deallocation provoked
pymalloc into handing out the same chunk of memory to two distinct objects
alive at the same time -- and that is, alas, a likely outcome).

I suspect these bugs hid for so long because it's taken Pythoneers a long
time to discover why weakrefs can be so cool, and start to build serious
apps on top of them.  Casual programmers aren't likely to use weakrefs at
all, but once you've built a cache based on weakrefs in a large app,
weakrefs become critical to your code and your design.

So I think either of these fixes is enough to justify a bugfix release, and
having two of them makes a compelling case.  What say we get 2.3.3 in
motion?  I did the weakref checkins already on the trunk and on
release23-maint; Thomas Heller confirmed that his problems went away on
release23-maint, and Jim Fulton confirmed that his Zope3 segfaults went away
on the released 2.3.2 + a patch identical in all functional respects to what
got checked in (the new test_weakref test cases, and some code comments,
were different).

If we get 2.3.3c1 out in early December, we could release 2.3.3 final before
the end of the year, and start 2004 with a 100% bug-free codebase <wink>.




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