Author vstinner
Recipients eli.bendersky, jkloth, scoder, serhiy.storchaka, vstinner
Date 2017-09-18.08:45:05
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Message-id <>
>> The question is more why/how the code didn't crash before? :-)
> Typical case of a Schroedinbug.

I don't believe in the chaos :-)

I ran a "git bisect" since January 1st, 2017. Attached started to crash since the following commit related to bpo-29049.
5a625d0aa6a6d9ec6574ee8344b41d63dcb9897e is the first bad commit
commit 5a625d0aa6a6d9ec6574ee8344b41d63dcb9897e
Author: INADA Naoki <>
Date:   Sat Dec 24 20:19:08 2016 +0900

    Issue #29049: Call _PyObject_GC_TRACK() lazily when calling Python function.
    Calling function is up to 5% faster.

This change is also correct. It's more that the change showed a bug which was hidden before.

It's just that now the garbage collector breaks the reference cycle differently since frames tracked differently by the GC.
Date User Action Args
2017-09-18 08:45:05vstinnersetrecipients: + vstinner, scoder, jkloth, eli.bendersky, serhiy.storchaka
2017-09-18 08:45:05vstinnersetmessageid: <>
2017-09-18 08:45:05vstinnerlinkissue31499 messages
2017-09-18 08:45:05vstinnercreate