New submission from Dennis Sweeney <sweeney.dennis...@gmail.com>:
In bpo-30570, David Bolen noticed that "py -3.9 -m test test_pickle"
consistently crashes on Windows (even though other methods of running that test
do not crash, and the test succeeds when failed tests are retried).
Curiously, it seems that adding using support.infinite_recursion *introduced*
the crash rather than preventing it.
I'm guessing this would have been fixed by GH-24501, but that fix was rolled
back in GH-25179 for the sake of 3.9 ABI compatibility.
As of now, 3.9's pycore_ceval.c reads:
static inline int _Py_RecursionLimitLowerWaterMark(int limit) {
if (limit > 200) {
return (limit - 50);
}
else {
return (3 * (limit >> 2));
}
}
But support.infinite_recursion(max_depth=75) has a default 75, leaving a
"low-water-mark" of 54, which the recursion apparently never recovers back to
in the right way.
A couple of solutions could fix this:
(1) Remove the usage of support.infinite_recursion at the
test.pickletester.AbstractPickleTests.test_bad_getattr call site.
(2) Use a different value max_depth. On my machine at least, it seems 75 was a
"perfect storm" to cause this issue. Using infinite_recursion(60) or 61 or ...
or 74 or 76 or 77 or 78 all pass, but infinite_recursion(75) in particular
fails.
(3) Use fewer calls after the overflow by inlining something like assertRaises:
with support.infinite_recursion():
- self.assertRaises(RuntimeError, self.dumps, x, proto)
+ try:
+ self.dumps(x, proto)
+ except RuntimeError:
+ pass
+ else:
+ self.fail("RuntimeError not raised")
(5) Re-visit an ABI-compliant version of GH-24501, such as GH-25160
The output I keep getting without any changes:
> py -3.9 -m test test_pickle -v
...
test_attribute_name_interning (test.test_pickle.CPicklerTests) ... ok
test_bad_getattr (test.test_pickle.CPicklerTests) ... Fatal Python error:
_Py_CheckRecursiveCall: Cannot recover from stack overflow.Python runtime
state: initialized
Current thread 0x000028b0 (most recent call first):
File "C:\Users\sween\Source\Repos\cpython2\39\lib\test\pickletester.py", line
3300 in __getattr__
File "C:\Users\sween\Source\Repos\cpython2\39\lib\test\pickletester.py", line
3300 in __getattr__
File "C:\Users\sween\Source\Repos\cpython2\39\lib\test\pickletester.py", line
3300 in __getattr__
...
File "C:\Users\sween\Source\Repos\cpython2\39\lib\test\pickletester.py", line
3300 in __getattr__
File "C:\Users\sween\Source\Repos\cpython2\39\lib\test\pickletester.py", line
3300 in __getattr__
File "C:\Users\sween\Source\Repos\cpython2\39\lib\test\pickletester.py", line
3300 in __getattr__
File "C:\Users\sween\Source\Repos\cpython2\39\lib\copyreg.py", line 74 in
_reduce_ex
File "C:\Users\sween\Source\Repos\cpython2\39\lib\test\test_pickle.py", line
65 in dumps
File "C:\Users\sween\Source\Repos\cpython2\39\lib\unittest\case.py", line 201
in handle
File "C:\Users\sween\Source\Repos\cpython2\39\lib\unittest\case.py", line 739
in assertRaises
File "C:\Users\sween\Source\Repos\cpython2\39\lib\test\pickletester.py", line
2381 in test_bad_getattr
File "C:\Users\sween\Source\Repos\cpython2\39\lib\test\support\__init__.py",
line 1770 in wrapper
File "C:\Users\sween\Source\Repos\cpython2\39\lib\unittest\case.py", line 550
in _callTestMethod
File "C:\Users\sween\Source\Repos\cpython2\39\lib\unittest\case.py", line 592
in run
File "C:\Users\sween\Source\Repos\cpython2\39\lib\unittest\case.py", line 651
in __call__
File "C:\Users\sween\Source\Repos\cpython2\39\lib\unittest\suite.py", line
122 in run
File "C:\Users\sween\Source\Repos\cpython2\39\lib\unittest\suite.py", line 84
in __call__
File "C:\Users\sween\Source\Repos\cpython2\39\lib\unittest\suite.py", line
122 in run
File "C:\Users\sween\Source\Repos\cpython2\39\lib\unittest\suite.py", line 84
in __call__
File "C:\Users\sween\Source\Repos\cpython2\39\lib\unittest\suite.py", line
122 in run
----------
components: Tests
messages: 406339
nosy: Dennis Sweeney, Mark.Shannon, lukasz.langa
priority: normal
severity: normal
status: open
title: Cannot Recover From StackOverflow in 3.9 Tests
type: crash
versions: Python 3.9
_______________________________________
Python tracker <rep...@bugs.python.org>
<https://bugs.python.org/issue45806>
_______________________________________
_______________________________________________
Python-bugs-list mailing list
Unsubscribe:
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
