[Python-Dev] Optimization of the Year

[Tim Peters]

[Armin Rigo]
> Unfortunately, the existence of the PyList_GET_XXX macros means
> that perfectly legal extension modules would break if you do something
> like changing the order of the fields.

The new field can be added at the end of the current list header struct.

> Is it more important to try and keep binary compatibility for these 99%,
> or to force a reproducible segfault in the remaining 1%?

That question didn't make sense <wink>.