Issue 1591996: in for classic object causes segfault (original) (raw)

Issue1591996

Created on 2006-11-07 13:32 by ocean-city, last changed 2022-04-11 14:56 by admin. This issue is now closed.

Messages (6)
msg51337 - (view)	Author: Hirokazu Yamamoto (ocean-city) *	Date: 2006-11-07 13:32
This code causes segfault. class Foo: pass foo = Foo() 1 in foo E:\python-dev>py a.py Exception exceptions.TypeError: "argument of type 'instance' is not iterable" in 'garbage collection' ignored Fatal Python error: unexpected exception during garbage collection This bug seems to be introduced by revision 45644 change for Objects/classobject.c # -1 (error) is converted to 0 (False) I think this can be fixed by attached patch. Thank you.
msg51338 - (view)	Author: Georg Brandl (georg.brandl) *	Date: 2006-11-07 15:39
Logged In: YES user_id=849994 Attaching to Martin since the mentioned revision is his.
msg51339 - (view)	Author: Neal Norwitz (nnorwitz) *	Date: 2006-11-08 06:28
Logged In: YES user_id=33168 I fixed the problem slightly differently without casting, but rather checking the result. The patch also contains a test case.
msg51340 - (view)	Author: Martin v. Löwis (loewis) *	Date: 2006-11-08 06:47
Logged In: YES user_id=21627 I agree with Neal's patch, committed as r52662 and r52663.
msg51341 - (view)	Author: Hirokazu Yamamoto (ocean-city) *	Date: 2006-11-08 07:06
Logged In: YES user_id=1200846 Sorry for posting to closed entry, but this is related... Maybe similar patch is apropriate for PySequence_Contains in Objects/abstract.c like this? Thank you. Index: Objects/abstract.c =================================================================== --- Objects/abstract.c (revision 52664) +++ Objects/abstract.c (working copy) @@ -1719,7 +1719,9 @@ return (*sqm->sq_contains)(seq, ob); } result = _PySequence_IterSearch(seq, ob, PY_ITERSEARCH_CONTAINS); - return Py_SAFE_DOWNCAST(result, Py_ssize_t, int); + if (result >= 0) + return result > 0; + return -1; } /* Backwards compatibility */
msg51342 - (view)	Author: Martin v. Löwis (loewis) *	Date: 2006-11-08 07:43
Logged In: YES user_id=21627 It's not strictly necessary, IMO: PY_ITERSEARCH_CONTAINS is guaranteed to return -1, 0, 1, just as PySequence_Contains should. So the safe downcast is correct. IOW, your patch would have been correct, as well. I liked Neal's patch more, because it combines the error cases into a single return, and because it had a test case.