gh-134411: assert PyLong_FromLong(x) != NULL when x is known to be small
#134415
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PyLong_FromLong sets an exception when it fails, so the call to PyObject_SetAttrString is unsafe. We should return NULL instead of switching to Py_XDECREF.
But, as @sergey-miryanov mentioned, this can't fail for integers <255. I think it's also reasonable to add an assertion here instead of adding error handling.
…case and can't return NULL. Added assert for extra confidence. python#134411 (comment)
ZeroIntensity
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needs backport to 3.13
ZeroIntensity
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May 21, 2025
Python/instrumentation.c
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| @@ -2558,18 +2558,22 @@ PyObject *_Py_CreateMonitoringObject(void) | |||
| err = PyObject_SetAttrString(events, "NO_EVENTS", _PyLong_GetZero()); | |||
| if (err) goto error; | |||
| PyObject *val = PyLong_FromLong(PY_MONITORING_DEBUGGER_ID); | |||
| assert(val != NULL); | |||
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I think it'd be a good idea to add a comment explaining why it can't ever fail.
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I'll add it tomorrow.
picnixz
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PyLong_FromLong(x) != NULL when x is known to be small
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Python/instrumentation.c: ensure non-NULLPyLong_FromLongresults when possible #134411