PyGILState_Rele ase + Python2.3 = Segmentation Fault

[Kirill Simonov]

Hi,

Could someone tell me why my extension module works under Python 2.4, but
fails with Segmentation Fault under Python 2.3? Here is the stripped version:

=============== =============== =============== ===
#include <Python.h>

static PyObject *
test_gil(PyObje ct *self)
{
PyGILState_STAT E gs;

Py_BEGIN_ALLOW_ THREADS

gs = PyGILState_Ensu re();

PyGILState_Rele ase(gs);

Py_END_ALLOW_TH READS

Py_INCREF(Py_No ne);
return Py_None;
}

static PyMethodDef test_gil_method s[] = {
{"test_gil", (PyCFunction)te st_gil, METH_NOARGS},
{NULL}
};

PyMODINIT_FUNC
init_test_gil(v oid) {
(void)Py_InitMo dule("_test_gil ", test_gil_method s);
}
=============== =============== =============== ==

I've tested it with Debian Sid and Ubuntu Breezy.

Thanks,
Kirill

[cadavis2k2]

Kirill Simonov wrote:

Hi,

Could someone tell me why my extension module works under Python 2.4, but
fails with Segmentation Fault under Python 2.3? Here is the stripped version:

Maybe Python threads aren't initialized? Adding a call to
PyEval_InitThre ads() stops the seg fault for me in Python 2.3 on
Debian:

#include <Python.h>

static PyObject *
test_gil(PyObje ct *self)
{
PyGILState_STAT E gs;
Py_BEGIN_ALLOW_ THREADS
gs = PyGILState_Ensu re();
PyGILState_Rele ase(gs);
Py_END_ALLOW_TH READS
Py_INCREF(Py_No ne);
return Py_None;
}
static PyMethodDef test_gil_method s[] = {
{"test_gil", (PyCFunction)te st_gil, METH_NOARGS},
{NULL}
};
PyMODINIT_FUNC
init_test_gil(v oid) {

/* This added */
PyEval_InitThre ads();

(void)Py_InitMo dule("_test_gil ", test_gil_method s);
}