[Patches] [ python-Patches-1630248 ] Implement named exception cleanup

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Patches item #1630248, was opened at 2007-01-07 22:02
Message generated for change (Comment added) made by collinwinter
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Category: Core (C code)
Group: Python 3000
Status: Open
Resolution: None
Priority: 5
Private: No
Submitted By: Collin Winter (collinwinter)
Assigned to: Nobody/Anonymous (nobody)
Summary: Implement named exception cleanup

Initial Comment:
This patch implements the solution outlined in http://mail.python.org/pipermail/python-3000/2007-January/005395.html for avoiding exception-related refcount cycles.

Specifically,

try:
  ...
except ExcType, e:
  #body

is translated to

try:
  ...
except ExcType, e:
  try:
    # body
  finally:
    e = None
    del e


The attached patches are against r53289. exc_cleanup.patch is the implementation and testcases, while stdlib_fixes.patch repairs all places in the stdlib that depended on the old behaviour.

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>Comment By: Collin Winter (collinwinter)
Date: 2007-01-08 11:51

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Patches updated in reponse to PJE's comment
(http://mail.python.org/pipermail/python-3000/2007-January/005430.html):

"""In the tuple or list case, there's no need to reset the variables,
because 
then the traceback won't be present any more; the exception object will 
have been discarded after unpacking."""

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Comment By: Collin Winter (collinwinter)
Date: 2007-01-08 11:50

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File Added: exc_cleanup.patch

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Comment By: Collin Winter (collinwinter)
Date: 2007-01-08 11:49

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File Added: stdlib_fixes.patch

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Comment By: Collin Winter (collinwinter)
Date: 2007-01-07 22:34

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This is the first time I've done this kind of surgery on the compiler, so
any tips/tricks/advice would be greatly appreciated.

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Comment By: Collin Winter (collinwinter)
Date: 2007-01-07 22:02

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File Added: stdlib_fixes.patch

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