[Python-bugs-list] [ python-Bugs-808594 ] leak on lambda with duplicate arguments error

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Bugs item #808594, was opened at 2003-09-18 14:43
Message generated for change (Comment added) made by jhylton
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Category: Parser/Compiler
Group: Python 2.3
>Status: Closed
>Resolution: Fixed
Priority: 5
Submitted By: Michael Hudson (mwh)
Assigned to: Jeremy Hylton (jhylton)
Summary: leak on lambda with duplicate arguments error

Initial Comment:
There's a leak on compiling code like 'lambda a,a:0'. 

TrackRefs says the following are being leaked:



<type 'list'>                                         

        4       16

<type 'str'>                                          

        2       10

<type 'symtable entry'>                               

        2        8

<type 'dict'>                                         

        2        8

<type 'int'>                                          

        0        2



It doesn't seem to leak for, e.g. 'def f(a,a):pass'.



I had a look at the code, but got very confused, I'm

afraid.

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>Comment By: Jeremy Hylton (jhylton)
Date: 2003-09-22 04:35

Message:
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But a more careful test shows that totalrefcount doesn't go

up if I compile this code in a loop.  So it looks like it's

fixed.



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Comment By: Jeremy Hylton (jhylton)
Date: 2003-09-22 04:32

Message:
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I changed the code, but I think I still see a leak.  At the

interpreter prompt,

f = lambda a,a: None

shows refs growing by one every time.



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Comment By: Michael Hudson (mwh)
Date: 2003-09-19 10:04

Message:
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Well, this was easier to fix than I expected (one line patch

attached, which I'll check in soon).



The mystery has transformed itself into "how the hell did

the code work in the first place?" and "why didn't the

function version leak?".



I think I know the answer to the first one, but I'm not

telling :-) I may go as far as posting it to c.l.py as a

Python Mystery Theatre style poser...

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