Author vstinner
Recipients gvanrossum, vstinner, yselivanov
Date 2015-07-09.14:04:04
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When storing an exception in an asyncio Future object, there is a high risk of creating a reference cycle. In Python 3, exception objects store a traceback object which store frame objects. The problem is that a frame can also have a reference to the exception: we have a reference cycle (exception -> traceback -> frame -> same exception).

In debug mode, Future.set_exception() can schedule a task (ex: using loop.call_soon) to check that there is no reference cycle.

See also the issue #23587: "asyncio: use the new traceback.TracebackException class".
Date User Action Args
2015-07-09 14:04:05vstinnersetrecipients: + vstinner, gvanrossum, yselivanov
2015-07-09 14:04:05vstinnersetmessageid: <>
2015-07-09 14:04:05vstinnerlinkissue24598 messages
2015-07-09 14:04:04vstinnercreate