[Python-bugs-list] [ python-Bugs-690622 ] test_cpickle overflows stack on MacOS9

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Bugs item #690622, was opened at 2003-02-21 07:15
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https://sourceforge.net/tracker/?func=detail&atid=105470&aid=690622&group_id=5470

Category: None
Group: None
Status: Open
Resolution: None
Priority: 5
Submitted By: Jack Jansen (jackjansen)
Assigned to: Jack Jansen (jackjansen)
Summary: test_cpickle overflows stack on MacOS9

Initial Comment:
Test_cpickle overflows the stack and hangs the interpreter on MacOS9. This happens in test_nonrecursive_deep(), in the dumps() call.

I think there's a PyOS_CheckStack() call missing somewhere in cPickle.

Also, it's probably a good idea to lower the recursion to 50 (the test passes as long as the recusrion is less than 65 deep), at least on MacOS9. 

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>Comment By: Tim Peters (tim_one)
Date: 2003-02-21 15:04

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Right, AFAICT 60 is enough to test what this is trying to test 
(although I'm not the "fast pickler" expert -- but I think it's 
clear enough).  Jack, please confirm that 60 is OK for you?

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Comment By: Guido van Rossum (gvanrossum)
Date: 2003-02-21 15:01

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I agree that I'd rather not see CheckStack calls added to
cPickle. But using 60 instead of 100 should work for both of
you, right?

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Comment By: Tim Peters (tim_one)
Date: 2003-02-21 14:55

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There are no PyOS_CheckStack()  calls in cPickle, and I'm 
not sure anyone really wants to bother adding them (cPickle 
is meant to be high-performance, not safe <wink>).

That test is consuming more stack frames than it used to, 
because each level of list pickling now bites another stack 
frame to call the new "batch list elements" routine.

Reducing to 50 doesn't fly because cPickle's internal 
PY_CPICKLE_FAST_LIMIT #define happens to be 50 now, 
and the purpose of test_nonrecursive_deep is to be sure that 
non-cyclic containers get pickled OK in a "fast" pickler even if 
they're nested as deeply as PY_CPICKLE_FAST_LIMIT.

Assigning to Guido for further cogitation on his day off <wink>.

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You can respond by visiting: 
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