Assertion failure in Python/optimizer.c _PyOptimizer_Optimize in JIT

[YuanchengJiang]

Crash report

What happened?

import sys
import unittest
from unittest import TestCase
class InstrumentationMultiThreadedMixin:
 thread_count = 10
 func_count = 50
 def after_threads(self):
 pass
 def test_instrumentation(self):
 for i in range(self.func_count):
 x = {}
 threads = []
 for i in range(self.thread_count):
 for t in threads:
 break
 self.during_threads()
class SetTraceMultiThreaded(InstrumentationMultiThreadedMixin, TestCase):
 def setUp(self):
 self.set = 2**31-1
 def after_test(self):
 self.assertTrue(self.called)
 def tearDown(self):
 sys.settrace(1023)
 def trace_func(self, frame, event, arg):
 return self.trace_func
 def during_threads(self):
 if self.set:
 sys.settrace(self.trace_func)
 t.join()
if __name__ == "__main__":
 unittest.main()

...
TypeError: 'int' object is not callable
python: ../Python/optimizer.c:121: _PyOptimizer_Optimize: Assertion `interp->jit' failed.
Aborted (core dumped)

CPython versions tested on:

CPython main branch

Operating systems tested on:

Linux

Output from running 'python -VV' on the command line:

No response

Linked PRs

• gh-140936: Fix JIT assertion crash at finalization if some generator is alive #140969
• [3.14] gh-140936: Fix JIT assertion crash at finalization if some generator is alive (GH-140969) #141494

[sergey-miryanov]

I think it would be better if you provided the building flags used to create the fuzzed version of python executable.

[YuanchengJiang]

building flag: --with-pydebug --enable-experimental-jit=yes --with-address-sanitizer

[sergey-miryanov]

Simplified MRE:

import sys
import unittest
from unittest import TestCase


class InstrumentationMultiThreadedMixin(TestCase):

 def setUp(self):
 sys.settrace(lambda *args:None)

 def tearDown(self):
 sys.settrace(1023)

 def test_instrumentation(self):
 assert False

if __name__ == "__main__":
 unittest.main()

Stacktrace to failed assert:

>	python315_d.dll!_PyOptimizer_Optimize(_PyInterpreterFrame * frame, _Py_CODEUNIT * start, _PyExecutorObject * * executor_ptr, int chain_depth) Line 121	C
 	python315_d.dll!_PyEval_EvalFrameDefault(_ts * tstate, _PyInterpreterFrame * frame, int throwflag) Line 7656	C
 	python315_d.dll!gen_send_ex2(_PyGenObject * gen, _object * arg, _object * * presult, int exc, int closing) Line 259	C
 	python315_d.dll!gen_send_ex(_PyGenObject * gen, _object * arg, int exc, int closing) Line 301	C
 	python315_d.dll!gen_close(_object * self, _object * args) Line 427	C
 	python315_d.dll!_PyGen_Finalize(_object * self) Line 129	C
 	python315_d.dll!PyObject_CallFinalizer(_object * self) Line 586	C
 	python315_d.dll!PyObject_CallFinalizerFromDealloc(_object * self) Line 605	C
 	python315_d.dll!gen_dealloc(_object * self) Line 169	C
 	python315_d.dll!_Py_Dealloc(_object * op) Line 3205	C
 	python315_d.dll!Py_DECREF(const char * filename, int lineno, _object * op) Line 403	C
 	python315_d.dll!clear_inline_values(_dictvalues * values) Line 7233	C
 	python315_d.dll!PyObject_ClearManagedDict(_object * obj) Line 7452	C
 	python315_d.dll!subtype_dealloc(_object * self) Line 2824	C
 	python315_d.dll!_Py_Dealloc(_object * op) Line 3205	C
 	python315_d.dll!Py_DECREF_MORTAL(const char * filename, int lineno, _object * op) Line 450	C
 	python315_d.dll!frame_dealloc(_object * op) Line 1953	C
 	python315_d.dll!_Py_Dealloc(_object * op) Line 3205	C
 	python315_d.dll!Py_DECREF(const char * filename, int lineno, _object * op) Line 403	C
 	python315_d.dll!tb_dealloc(_object * op) Line 246	C
 	python315_d.dll!_Py_Dealloc(_object * op) Line 3205	C
 	python315_d.dll!Py_DECREF(const char * filename, int lineno, _object * op) Line 403	C
 	python315_d.dll!tb_dealloc(_object * op) Line 245	C
 	python315_d.dll!_Py_Dealloc(_object * op) Line 3205	C
 	python315_d.dll!Py_DECREF(const char * filename, int lineno, _object * op) Line 403	C
 	python315_d.dll!tb_dealloc(_object * op) Line 245	C
 	python315_d.dll!_Py_Dealloc(_object * op) Line 3205	C
 	python315_d.dll!Py_DECREF(const char * filename, int lineno, _object * op) Line 403	C
 	python315_d.dll!tb_dealloc(_object * op) Line 245	C
 	python315_d.dll!_Py_Dealloc(_object * op) Line 3205	C
 	python315_d.dll!Py_DECREF(const char * filename, int lineno, _object * op) Line 403	C
 	python315_d.dll!tb_dealloc(_object * op) Line 245	C
 	python315_d.dll!_Py_Dealloc(_object * op) Line 3205	C
 	python315_d.dll!Py_DECREF(const char * filename, int lineno, _object * op) Line 403	C
 	python315_d.dll!tb_dealloc(_object * op) Line 245	C
 	python315_d.dll!_Py_Dealloc(_object * op) Line 3205	C
 	python315_d.dll!Py_DECREF(const char * filename, int lineno, _object * op) Line 403	C
 	python315_d.dll!tb_dealloc(_object * op) Line 245	C
 	python315_d.dll!_Py_Dealloc(_object * op) Line 3205	C
 	python315_d.dll!Py_DECREF(const char * filename, int lineno, _object * op) Line 403	C
 	python315_d.dll!tb_dealloc(_object * op) Line 245	C
 	python315_d.dll!_Py_Dealloc(_object * op) Line 3205	C
 	python315_d.dll!Py_DECREF(const char * filename, int lineno, _object * op) Line 403	C
 	python315_d.dll!tb_dealloc(_object * op) Line 245	C
 	python315_d.dll!_Py_Dealloc(_object * op) Line 3205	C
 	python315_d.dll!Py_DECREF(const char * filename, int lineno, _object * op) Line 403	C
 	python315_d.dll!tb_dealloc(_object * op) Line 245	C
 	python315_d.dll!_Py_Dealloc(_object * op) Line 3205	C
 	python315_d.dll!Py_DECREF(const char * filename, int lineno, _object * op) Line 403	C
 	python315_d.dll!tb_dealloc(_object * op) Line 245	C
 	python315_d.dll!_Py_Dealloc(_object * op) Line 3205	C
 	python315_d.dll!Py_DECREF(const char * filename, int lineno, _object * op) Line 403	C
 	python315_d.dll!insertdict(_is * interp, PyDictObject * mp, _object * key, __int64 hash, _object * value) Line 1928	C
 	python315_d.dll!setitem_take2_lock_held(PyDictObject * mp, _object * key, _object * value) Line 2677	C
 	python315_d.dll!_PyDict_SetItem_Take2(PyDictObject * mp, _object * key, _object * value) Line 2684	C
 	python315_d.dll!PyDict_SetItem(_object * op, _object * key, _object * value) Line 2706	C
 	python315_d.dll!PyDict_SetItemString(_object * v, const char * key, _object * item) Line 5059	C
 	python315_d.dll!_PySys_ClearAttrString(_is * interp, const char * name, int verbose) Line 222	C
 	python315_d.dll!finalize_modules_delete_special(_ts * tstate, int verbose) Line 1530	C
 	python315_d.dll!finalize_modules(_ts * tstate) Line 1746	C
 	python315_d.dll!_Py_Finalize(pyruntimestate * runtime) Line 2259	C
 	python315_d.dll!Py_FinalizeEx() Line 2380	C
 	python315_d.dll!Py_RunMain() Line 774	C
 	python315_d.dll!pymain_main(_PyArgv * args) Line 803	C
 	python315_d.dll!Py_Main(int argc, wchar_t * * argv) Line 815	C
 	python_d.exe!wmain(int argc, wchar_t * * argv) Line 10	C

cc @Fidget-Spinner

[Fidget-Spinner]

I can reproduce this using my new JIT frontend as well. Probably a bug in the specialization/JIT detection.

[efimov-mikhail]

FYI, I've made some repro without using stdlib:

import sys

def simple_for():
 for x in (1, 2): 
 x

def gen():
 try:
 yield
 except:
 simple_for()

sys.settrace(lambda *args: None)
simple_for()
g = gen()
next(g)

[efimov-mikhail]

It seems that I've found a simple solution.