[issue44563] Failed tee.fromiterable() corrupts the linked list of all GC objects in debug build

[Serhiy Storchaka]

New submission from Serhiy Storchaka <storchaka+cpython at gmail.com>:

In tee.fromiterable() the non-initialized tee object can be deleted by  without calling _Py_ForgetReference() in debug build.

See also issue44553 and issue44562.

The proposed PR rewrites the code so that it no longer need to delete not completely initialized tee object.

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components: Extension Modules
messages: 396952
nosy: kj, pablogsal, rhettinger, serhiy.storchaka
priority: normal
severity: normal
status: open
title: Failed tee.fromiterable() corrupts the linked list of all GC objects in debug build
type: crash
versions: Python 3.10, Python 3.11, Python 3.9

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Python tracker <report at bugs.python.org>
<https://bugs.python.org/issue44563>
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