Preparing a post about lafleur, the CPython JIT fuzzer I develop.
It has found 4 JIT crashes so far:
#136996: "JIT: `executor->vm_data.valid` assertion failure in `unlink_executor`".
#137007: "JIT: assertion failure in _PyObject_GC_UNTRACK".
#137728: "Assertion failure or `SystemError` in `_PyEval_EvalFrameDefault` in a JIT build".
#137762: "Assertion failure in `optimize_uops` in a JIT build".
Contributions welcome!
https://github.com/search?q=repo%3Apython%2Fcpython+lafleur&type=issues
#Python #CPython #fuzzer #fuzzing #lafleur #JIT
danzin
npub1dl…puxsy
2025-08-16 20:56:11 UTC
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"content": "Preparing a post about lafleur, the CPython JIT fuzzer I develop.\n\nIt has found 4 JIT crashes so far:\n#136996: \"JIT: `executor-\u003evm_data.valid` assertion failure in `unlink_executor`\".\n#137007: \"JIT: assertion failure in _PyObject_GC_UNTRACK\".\n#137728: \"Assertion failure or `SystemError` in `_PyEval_EvalFrameDefault` in a JIT build\".\n#137762: \"Assertion failure in `optimize_uops` in a JIT build\".\n\nContributions welcome!\n\nhttps://github.com/search?q=repo%3Apython%2Fcpython+lafleur\u0026type=issues\n\n#Python #CPython #fuzzer #fuzzing #lafleur #JIT",
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