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The C API function 'PyList_Reverse()' causes a 'Segmentation
Fault(core dump)' when used under:
Python 2.0 (#1, Oct 27 2000, 09:38:44) [C] on sunos5
A simple C function was written to accept a Python list as
input and return it in reverse using 'PyList_Reverse()'.
When compiled under Python1.5.2, this code works flawlessly.
I use the function under Python in this manner:
Python 1.5.2 (#2, Apr 17 1999, 11:16:17) [C] on sunos5
Copyright 1991-1995 Stichting Mathematisch Centrum, Amsterdam
>>> import casette
>>> shape = casette.casette([1,2,3,4])
>>> shape
[4, 3, 2, 1]
However, when compiled under Python2.0, it returns the
following error:
Python 2.0 (#1, Oct 27 2000, 09:38:44) [C] on sunos5
Type "copyright", "credits" or "license" for more information.
>>> import casette
>>> shape = casette.casette([1,2,3,4])
Segmentation fault (core dumped)
and exits from Python altogether. 
I can provide the test program (with Makefile) if it 
would help track down the bug. Any indication of the
cause of this bug or a work around would be appreciated.

Raised priority, assigned to me.
Offhand, looks like one of those cases where the worker function (listreverse) was changed to use PyArg_ParseTuple, but the API wrapper function (PyList_Reverse) passes NULL for args instead of an empty tuple. Boom. list.reverse() at Python level uses the worker function directly. so only an extension module would bump into this (PyList_Reverse isn't used anywhere within Python).
whack, this should get fixed for the 2.1b1 release. In the meantime, try invoking the reverse *method* on your list object.

I'll take care of this.

Related patches checked in:
_testcapimodule.c rev 1.2
 make sure PyList_Reverse doesn't blow up again
getargs.c rev 2.54
 assert args isn't NULL at the top of vgetargs1 instead of
 waiting for a NULL-pointer dereference at the end

All taken care of.

Change Resolution to Fixed. The fix is in listobject.c rev 2.92.