pyframe_getback Crash

main.c

#define PY_SSIZE_T_CLEAN
#include <Python.h>
#include "frameobject.h"

void DebugPrintObjects(unsigned int arg_count, ...)
{
    unsigned int i;
    va_list vargs;
    va_start(vargs, arg_count);

    if (!arg_count) {
        return;
    }

    for (i=0; i<arg_count; i++) {
        PyObject_Print(va_arg(vargs, PyObject *), stdout, Py_PRINT_RAW);
    }
    printf("\n");
    va_end(vargs);
}

int
PyTraceFunction(
        PyObject* obj,
        PyFrameObject* frame,
        int what,
        PyObject* arg)
{
    DebugPrintObjects(1, frame);
    PyFrame_GetBack(frame);

    return 0;
}

static PyObject *
set_trace(PyObject*a, PyObject*b)
{
    PyEval_SetProfile(PyTraceFunction, NULL);
    Py_RETURN_NONE;
}

static PyObject *
frame_new(PyObject *self, PyObject *args)
{
    PyObject *code, *globals, *locals;
    if (!PyArg_ParseTuple(args, "OOO", &code, &globals, &locals)) {
        return NULL;
    }
    if (!PyCode_Check(code)) {
        PyErr_SetString(PyExc_TypeError, "argument must be a code object");
        return NULL;
    }
    PyThreadState *tstate = PyThreadState_Get();

    return (PyObject *)PyFrame_New(tstate, (PyCodeObject *)code, globals, locals);
}


static PyMethodDef methods[] = {
        {"set_trace", set_trace, METH_NOARGS, "set_trace"},
        {"frame_new", frame_new, METH_VARARGS, NULL},
        {NULL, NULL, 0, NULL},
};

static struct PyModuleDef moduledef = {PyModuleDef_HEAD_INIT, "zzz", "", -1, methods};

PyMODINIT_FUNC
PyInit_zzz(void)
{
    return PyModule_Create(&moduledef);
}

main.py

import zzz

zzz.set_trace()

#from spacy.tokens import Doc

def dummy():
    pass

frame = zzz.frame_new(dummy.__code__, globals(), locals())
print(frame.f_back)

setup.py

from setuptools import Extension, setup

setup(
    version="1.0",
    ext_modules=[Extension(
        "zzz",
        sources=["main.c"],
    )],
    description="zzz",
)