Do we consider these overflows as bugs in Python, or do we declare that we expect compilers to "do the right thing" for the bug fix releases (i.e. care only about the default branch). I'd personally vote for the latter - i.e. don't apply any of the resulting changes to the maintenance releases, and target the issue only for 3.3.

Realistically, a compiler that invokes truly undefined behavior for signed overflow has no chance of getting 3.2 compiled correctly, and we have no chance of finding all these issues within the lifetime of 3.2.

If that is agreed, I would start committing changes that fix the issues Mark already discussed in 2009 (unless he wants to commit them himself).