[issue22996] Order of _io objects finalization can lose data in reference cycles

[Serhiy Storchaka]

Serhiy Storchaka added the comment:

I think that reference loop breaker should be smarter. If we have a loop

    A ⇄ B → C → D

then the order of the finalization of A and B is not defined, but B should be finalized before C and C before D. This should fix unintentional issues with chained io classes because they have no back references.

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Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue22996>
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