On 03.03.25 11:17, Peter Eisentraut wrote:
Update for the hackers list: This patch set was briefly committed but
had to be reverted because it crashed on some older Python versions; see
[0].
I have locally reproduced the problem with Python 3.6 and 3.7; Python
3.8 is ok. This matches the results from the buildfarm.
I have poked at this a bit more but haven't gotten a good idea where or
how to fix it so far. Help welcome.
I have figured this out. There was a Python API change/bugfix between
3.7 and 3.8 that directly affects this patch. The relevant commit is
<https://github.com/python/cpython/commit/364f0b0f19c>. I have applied
the workarounds described there to my patch set, and now it works for
3.6 and 3.7 as well.From d28601d504dff57c49089f3adcaf0dce83893d83 Mon Sep 17 00:00:00 2001
From: Peter Eisentraut <pe...@eisentraut.org>
Date: Wed, 5 Mar 2025 17:38:06 +0100
Subject: [PATCH v3 1/2] Prepare for Python "Limited API" in PL/Python
Using the Python Limited API would allow building PL/Python against
any Python 3.x version and using another Python 3.x version at run
time. This commit does not activate that, but it prepares the code to
only use APIs supported by the Limited API.
Implementation details:
- Convert static types to heap types
(https://docs.python.org/3/howto/isolating-extensions.html#heap-types).
- Replace PyRun_String() with component functions.
- Replace PyList_SET_ITEM() with PyList_SetItem().
Discussion:
https://www.postgresql.org/message-id/flat/ee410de1-1e0b-4770-b125-eeefd4726...@eisentraut.org
---
src/pl/plpython/plpy_cursorobject.c | 84 +++++++++++++++------
src/pl/plpython/plpy_planobject.c | 70 +++++++++++------
src/pl/plpython/plpy_procedure.c | 5 +-
src/pl/plpython/plpy_resultobject.c | 109 +++++++++++++++++----------
src/pl/plpython/plpy_subxactobject.c | 46 ++++++-----
src/pl/plpython/plpy_typeio.c | 6 +-
6 files changed, 213 insertions(+), 107 deletions(-)
diff --git a/src/pl/plpython/plpy_cursorobject.c
b/src/pl/plpython/plpy_cursorobject.c
index bb3fa8a3909..1c6be756120 100644
--- a/src/pl/plpython/plpy_cursorobject.c
+++ b/src/pl/plpython/plpy_cursorobject.c
@@ -20,7 +20,7 @@
#include "utils/memutils.h"
static PyObject *PLy_cursor_query(const char *query);
-static void PLy_cursor_dealloc(PyObject *arg);
+static void PLy_cursor_dealloc(PLyCursorObject *self);
static PyObject *PLy_cursor_iternext(PyObject *self);
static PyObject *PLy_cursor_fetch(PyObject *self, PyObject *args);
static PyObject *PLy_cursor_close(PyObject *self, PyObject *unused);
@@ -33,22 +33,43 @@ static PyMethodDef PLy_cursor_methods[] = {
{NULL, NULL, 0, NULL}
};
-static PyTypeObject PLy_CursorType = {
- PyVarObject_HEAD_INIT(NULL, 0)
- .tp_name = "PLyCursor",
- .tp_basicsize = sizeof(PLyCursorObject),
- .tp_dealloc = PLy_cursor_dealloc,
- .tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE,
- .tp_doc = PLy_cursor_doc,
- .tp_iter = PyObject_SelfIter,
- .tp_iternext = PLy_cursor_iternext,
- .tp_methods = PLy_cursor_methods,
+static PyType_Slot PLyCursor_slots[] =
+{
+ {
+ Py_tp_dealloc, PLy_cursor_dealloc
+ },
+ {
+ Py_tp_doc, (char *) PLy_cursor_doc
+ },
+ {
+ Py_tp_iter, PyObject_SelfIter
+ },
+ {
+ Py_tp_iternext, PLy_cursor_iternext
+ },
+ {
+ Py_tp_methods, PLy_cursor_methods
+ },
+ {
+ 0, NULL
+ }
};
+static PyType_Spec PLyCursor_spec =
+{
+ .name = "PLyCursor",
+ .basicsize = sizeof(PLyCursorObject),
+ .flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE,
+ .slots = PLyCursor_slots,
+};
+
+static PyTypeObject *PLy_CursorType;
+
void
PLy_cursor_init_type(void)
{
- if (PyType_Ready(&PLy_CursorType) < 0)
+ PLy_CursorType = (PyTypeObject *) PyType_FromSpec(&PLyCursor_spec);
+ if (!PLy_CursorType)
elog(ERROR, "could not initialize PLy_CursorType");
}
@@ -80,8 +101,12 @@ PLy_cursor_query(const char *query)
volatile MemoryContext oldcontext;
volatile ResourceOwner oldowner;
- if ((cursor = PyObject_New(PLyCursorObject, &PLy_CursorType)) == NULL)
+ if ((cursor = PyObject_New(PLyCursorObject, PLy_CursorType)) == NULL)
return NULL;
+#if PY_VERSION_HEX < 0x03080000
+ /* Workaround for Python issue 35810; no longer necessary in Python 3.8
*/
+ Py_INCREF(PLy_CursorType);
+#endif
cursor->portalname = NULL;
cursor->closed = false;
cursor->mcxt = AllocSetContextCreate(TopMemoryContext,
@@ -177,8 +202,12 @@ PLy_cursor_plan(PyObject *ob, PyObject *args)
return NULL;
}
- if ((cursor = PyObject_New(PLyCursorObject, &PLy_CursorType)) == NULL)
+ if ((cursor = PyObject_New(PLyCursorObject, PLy_CursorType)) == NULL)
return NULL;
+#if PY_VERSION_HEX < 0x03080000
+ /* Workaround for Python issue 35810; no longer necessary in Python 3.8
*/
+ Py_INCREF(PLy_CursorType);
+#endif
cursor->portalname = NULL;
cursor->closed = false;
cursor->mcxt = AllocSetContextCreate(TopMemoryContext,
@@ -272,30 +301,35 @@ PLy_cursor_plan(PyObject *ob, PyObject *args)
}
static void
-PLy_cursor_dealloc(PyObject *arg)
+PLy_cursor_dealloc(PLyCursorObject *self)
{
- PLyCursorObject *cursor;
+#if PY_VERSION_HEX >= 0x03080000
+ PyTypeObject *tp = Py_TYPE(self);
+#endif
Portal portal;
- cursor = (PLyCursorObject *) arg;
-
- if (!cursor->closed)
+ if (!self->closed)
{
- portal = GetPortalByName(cursor->portalname);
+ portal = GetPortalByName(self->portalname);
if (PortalIsValid(portal))
{
UnpinPortal(portal);
SPI_cursor_close(portal);
}
- cursor->closed = true;
+ self->closed = true;
}
- if (cursor->mcxt)
+ if (self->mcxt)
{
- MemoryContextDelete(cursor->mcxt);
- cursor->mcxt = NULL;
+ MemoryContextDelete(self->mcxt);
+ self->mcxt = NULL;
}
- arg->ob_type->tp_free(arg);
+
+ PyObject_Free(self);
+#if PY_VERSION_HEX >= 0x03080000
+ /* This was not needed before Python 3.8 (Python issue 35810) */
+ Py_DECREF(tp);
+#endif
}
static PyObject *
diff --git a/src/pl/plpython/plpy_planobject.c
b/src/pl/plpython/plpy_planobject.c
index 9427674d2f4..3e385555e5e 100644
--- a/src/pl/plpython/plpy_planobject.c
+++ b/src/pl/plpython/plpy_planobject.c
@@ -12,7 +12,7 @@
#include "plpython.h"
#include "utils/memutils.h"
-static void PLy_plan_dealloc(PyObject *arg);
+static void PLy_plan_dealloc(PLyPlanObject *self);
static PyObject *PLy_plan_cursor(PyObject *self, PyObject *args);
static PyObject *PLy_plan_execute(PyObject *self, PyObject *args);
static PyObject *PLy_plan_status(PyObject *self, PyObject *args);
@@ -26,20 +26,37 @@ static PyMethodDef PLy_plan_methods[] = {
{NULL, NULL, 0, NULL}
};
-static PyTypeObject PLy_PlanType = {
- PyVarObject_HEAD_INIT(NULL, 0)
- .tp_name = "PLyPlan",
- .tp_basicsize = sizeof(PLyPlanObject),
- .tp_dealloc = PLy_plan_dealloc,
- .tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE,
- .tp_doc = PLy_plan_doc,
- .tp_methods = PLy_plan_methods,
+static PyType_Slot PLyPlan_slots[] =
+{
+ {
+ Py_tp_dealloc, PLy_plan_dealloc
+ },
+ {
+ Py_tp_doc, (char *) PLy_plan_doc
+ },
+ {
+ Py_tp_methods, PLy_plan_methods
+ },
+ {
+ 0, NULL
+ }
};
+static PyType_Spec PLyPlan_spec =
+{
+ .name = "PLyPlan",
+ .basicsize = sizeof(PLyPlanObject),
+ .flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE,
+ .slots = PLyPlan_slots,
+};
+
+static PyTypeObject *PLy_PlanType;
+
void
PLy_plan_init_type(void)
{
- if (PyType_Ready(&PLy_PlanType) < 0)
+ PLy_PlanType = (PyTypeObject *) PyType_FromSpec(&PLyPlan_spec);
+ if (!PLy_PlanType)
elog(ERROR, "could not initialize PLy_PlanType");
}
@@ -48,8 +65,12 @@ PLy_plan_new(void)
{
PLyPlanObject *ob;
- if ((ob = PyObject_New(PLyPlanObject, &PLy_PlanType)) == NULL)
+ if ((ob = PyObject_New(PLyPlanObject, PLy_PlanType)) == NULL)
return NULL;
+#if PY_VERSION_HEX < 0x03080000
+ /* Workaround for Python issue 35810; no longer necessary in Python 3.8
*/
+ Py_INCREF(PLy_PlanType);
+#endif
ob->plan = NULL;
ob->nargs = 0;
@@ -63,25 +84,32 @@ PLy_plan_new(void)
bool
is_PLyPlanObject(PyObject *ob)
{
- return ob->ob_type == &PLy_PlanType;
+ return ob->ob_type == PLy_PlanType;
}
static void
-PLy_plan_dealloc(PyObject *arg)
+PLy_plan_dealloc(PLyPlanObject *self)
{
- PLyPlanObject *ob = (PLyPlanObject *) arg;
+#if PY_VERSION_HEX >= 0x03080000
+ PyTypeObject *tp = Py_TYPE(self);
+#endif
- if (ob->plan)
+ if (self->plan)
{
- SPI_freeplan(ob->plan);
- ob->plan = NULL;
+ SPI_freeplan(self->plan);
+ self->plan = NULL;
}
- if (ob->mcxt)
+ if (self->mcxt)
{
- MemoryContextDelete(ob->mcxt);
- ob->mcxt = NULL;
+ MemoryContextDelete(self->mcxt);
+ self->mcxt = NULL;
}
- arg->ob_type->tp_free(arg);
+
+ PyObject_Free(self);
+#if PY_VERSION_HEX >= 0x03080000
+ /* This was not needed before Python 3.8 (Python issue 35810) */
+ Py_DECREF(tp);
+#endif
}
diff --git a/src/pl/plpython/plpy_procedure.c b/src/pl/plpython/plpy_procedure.c
index c35a3b801ab..b494eeb474f 100644
--- a/src/pl/plpython/plpy_procedure.c
+++ b/src/pl/plpython/plpy_procedure.c
@@ -350,6 +350,7 @@ PLy_procedure_compile(PLyProcedure *proc, const char *src)
{
PyObject *crv = NULL;
char *msrc;
+ PyObject *code0;
proc->globals = PyDict_Copy(PLy_interp_globals);
@@ -368,7 +369,9 @@ PLy_procedure_compile(PLyProcedure *proc, const char *src)
msrc = PLy_procedure_munge_source(proc->pyname, src);
/* Save the mangled source for later inclusion in tracebacks */
proc->src = MemoryContextStrdup(proc->mcxt, msrc);
- crv = PyRun_String(msrc, Py_file_input, proc->globals, NULL);
+ code0 = Py_CompileString(msrc, "<string>", Py_file_input);
+ if (code0)
+ crv = PyEval_EvalCode(code0, proc->globals, NULL);
pfree(msrc);
if (crv != NULL)
diff --git a/src/pl/plpython/plpy_resultobject.c
b/src/pl/plpython/plpy_resultobject.c
index 95acce65493..80fa1d7accc 100644
--- a/src/pl/plpython/plpy_resultobject.c
+++ b/src/pl/plpython/plpy_resultobject.c
@@ -10,7 +10,7 @@
#include "plpy_resultobject.h"
#include "plpython.h"
-static void PLy_result_dealloc(PyObject *arg);
+static void PLy_result_dealloc(PLyResultObject *self);
static PyObject *PLy_result_colnames(PyObject *self, PyObject *unused);
static PyObject *PLy_result_coltypes(PyObject *self, PyObject *unused);
static PyObject *PLy_result_coltypmods(PyObject *self, PyObject *unused);
@@ -24,17 +24,6 @@ static int PLy_result_ass_subscript(PyObject *arg,
PyObject *item, PyObject *val
static char PLy_result_doc[] = "Results of a PostgreSQL query";
-static PySequenceMethods PLy_result_as_sequence = {
- .sq_length = PLy_result_length,
- .sq_item = PLy_result_item,
-};
-
-static PyMappingMethods PLy_result_as_mapping = {
- .mp_length = PLy_result_length,
- .mp_subscript = PLy_result_subscript,
- .mp_ass_subscript = PLy_result_ass_subscript,
-};
-
static PyMethodDef PLy_result_methods[] = {
{"colnames", PLy_result_colnames, METH_NOARGS, NULL},
{"coltypes", PLy_result_coltypes, METH_NOARGS, NULL},
@@ -44,23 +33,55 @@ static PyMethodDef PLy_result_methods[] = {
{NULL, NULL, 0, NULL}
};
-static PyTypeObject PLy_ResultType = {
- PyVarObject_HEAD_INIT(NULL, 0)
- .tp_name = "PLyResult",
- .tp_basicsize = sizeof(PLyResultObject),
- .tp_dealloc = PLy_result_dealloc,
- .tp_as_sequence = &PLy_result_as_sequence,
- .tp_as_mapping = &PLy_result_as_mapping,
- .tp_str = &PLy_result_str,
- .tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE,
- .tp_doc = PLy_result_doc,
- .tp_methods = PLy_result_methods,
+static PyType_Slot PLyResult_slots[] =
+{
+ {
+ Py_tp_dealloc, PLy_result_dealloc
+ },
+ {
+ Py_sq_length, PLy_result_length
+ },
+ {
+ Py_sq_item, PLy_result_item
+ },
+ {
+ Py_mp_length, PLy_result_length
+ },
+ {
+ Py_mp_subscript, PLy_result_subscript
+ },
+ {
+ Py_mp_ass_subscript, PLy_result_ass_subscript
+ },
+ {
+ Py_tp_str, PLy_result_str
+ },
+ {
+ Py_tp_doc, (char *) PLy_result_doc
+ },
+ {
+ Py_tp_methods, PLy_result_methods
+ },
+ {
+ 0, NULL
+ }
+};
+
+static PyType_Spec PLyResult_spec =
+{
+ .name = "PLyResult",
+ .basicsize = sizeof(PLyResultObject),
+ .flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE,
+ .slots = PLyResult_slots,
};
+static PyTypeObject *PLy_ResultType;
+
void
PLy_result_init_type(void)
{
- if (PyType_Ready(&PLy_ResultType) < 0)
+ PLy_ResultType = (PyTypeObject *) PyType_FromSpec(&PLyResult_spec);
+ if (!PLy_ResultType)
elog(ERROR, "could not initialize PLy_ResultType");
}
@@ -69,8 +90,12 @@ PLy_result_new(void)
{
PLyResultObject *ob;
- if ((ob = PyObject_New(PLyResultObject, &PLy_ResultType)) == NULL)
+ if ((ob = PyObject_New(PLyResultObject, PLy_ResultType)) == NULL)
return NULL;
+#if PY_VERSION_HEX < 0x03080000
+ /* Workaround for Python issue 35810; no longer necessary in Python 3.8
*/
+ Py_INCREF(PLy_ResultType);
+#endif
/* ob->tuples = NULL; */
@@ -89,20 +114,26 @@ PLy_result_new(void)
}
static void
-PLy_result_dealloc(PyObject *arg)
+PLy_result_dealloc(PLyResultObject *self)
{
- PLyResultObject *ob = (PLyResultObject *) arg;
-
- Py_XDECREF(ob->nrows);
- Py_XDECREF(ob->rows);
- Py_XDECREF(ob->status);
- if (ob->tupdesc)
+#if PY_VERSION_HEX >= 0x03080000
+ PyTypeObject *tp = Py_TYPE(self);
+#endif
+
+ Py_XDECREF(self->nrows);
+ Py_XDECREF(self->rows);
+ Py_XDECREF(self->status);
+ if (self->tupdesc)
{
- FreeTupleDesc(ob->tupdesc);
- ob->tupdesc = NULL;
+ FreeTupleDesc(self->tupdesc);
+ self->tupdesc = NULL;
}
- arg->ob_type->tp_free(arg);
+ PyObject_Free(self);
+#if PY_VERSION_HEX >= 0x03080000
+ /* This was not needed before Python 3.8 (Python issue 35810) */
+ Py_DECREF(tp);
+#endif
}
static PyObject *
@@ -125,7 +156,7 @@ PLy_result_colnames(PyObject *self, PyObject *unused)
{
Form_pg_attribute attr = TupleDescAttr(ob->tupdesc, i);
- PyList_SET_ITEM(list, i,
PLyUnicode_FromString(NameStr(attr->attname)));
+ PyList_SetItem(list, i,
PLyUnicode_FromString(NameStr(attr->attname)));
}
return list;
@@ -151,7 +182,7 @@ PLy_result_coltypes(PyObject *self, PyObject *unused)
{
Form_pg_attribute attr = TupleDescAttr(ob->tupdesc, i);
- PyList_SET_ITEM(list, i, PyLong_FromLong(attr->atttypid));
+ PyList_SetItem(list, i, PyLong_FromLong(attr->atttypid));
}
return list;
@@ -177,7 +208,7 @@ PLy_result_coltypmods(PyObject *self, PyObject *unused)
{
Form_pg_attribute attr = TupleDescAttr(ob->tupdesc, i);
- PyList_SET_ITEM(list, i, PyLong_FromLong(attr->atttypmod));
+ PyList_SetItem(list, i, PyLong_FromLong(attr->atttypmod));
}
return list;
@@ -227,7 +258,7 @@ PLy_result_str(PyObject *arg)
PLyResultObject *ob = (PLyResultObject *) arg;
return PyUnicode_FromFormat("<%s status=%S nrows=%S rows=%S>",
-
Py_TYPE(ob)->tp_name,
+ "PLyResult",
ob->status,
ob->nrows,
ob->rows);
diff --git a/src/pl/plpython/plpy_subxactobject.c
b/src/pl/plpython/plpy_subxactobject.c
index 5c92a0e089a..ad24a9fc4b8 100644
--- a/src/pl/plpython/plpy_subxactobject.c
+++ b/src/pl/plpython/plpy_subxactobject.c
@@ -15,7 +15,6 @@
List *explicit_subtransactions = NIL;
-static void PLy_subtransaction_dealloc(PyObject *subxact);
static PyObject *PLy_subtransaction_enter(PyObject *self, PyObject *unused);
static PyObject *PLy_subtransaction_exit(PyObject *self, PyObject *args);
@@ -31,21 +30,35 @@ static PyMethodDef PLy_subtransaction_methods[] = {
{NULL, NULL, 0, NULL}
};
-static PyTypeObject PLy_SubtransactionType = {
- PyVarObject_HEAD_INIT(NULL, 0)
- .tp_name = "PLySubtransaction",
- .tp_basicsize = sizeof(PLySubtransactionObject),
- .tp_dealloc = PLy_subtransaction_dealloc,
- .tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE,
- .tp_doc = PLy_subtransaction_doc,
- .tp_methods = PLy_subtransaction_methods,
+static PyType_Slot PLySubtransaction_slots[] =
+{
+ {
+ Py_tp_doc, (char *) PLy_subtransaction_doc
+ },
+ {
+ Py_tp_methods, PLy_subtransaction_methods
+ },
+ {
+ 0, NULL
+ }
};
+static PyType_Spec PLySubtransaction_spec =
+{
+ .name = "PLySubtransaction",
+ .basicsize = sizeof(PLySubtransactionObject),
+ .flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE,
+ .slots = PLySubtransaction_slots,
+};
+
+static PyTypeObject *PLy_SubtransactionType;
+
void
PLy_subtransaction_init_type(void)
{
- if (PyType_Ready(&PLy_SubtransactionType) < 0)
+ PLy_SubtransactionType = (PyTypeObject *)
PyType_FromSpec(&PLySubtransaction_spec);
+ if (!PLy_SubtransactionType)
elog(ERROR, "could not initialize PLy_SubtransactionType");
}
@@ -55,10 +68,13 @@ PLy_subtransaction_new(PyObject *self, PyObject *unused)
{
PLySubtransactionObject *ob;
- ob = PyObject_New(PLySubtransactionObject, &PLy_SubtransactionType);
-
+ ob = PyObject_New(PLySubtransactionObject, PLy_SubtransactionType);
if (ob == NULL)
return NULL;
+#if PY_VERSION_HEX < 0x03080000
+ /* Workaround for Python issue 35810; no longer necessary in Python 3.8
*/
+ Py_INCREF(PLy_SubtransactionType);
+#endif
ob->started = false;
ob->exited = false;
@@ -66,12 +82,6 @@ PLy_subtransaction_new(PyObject *self, PyObject *unused)
return (PyObject *) ob;
}
-/* Python requires a dealloc function to be defined */
-static void
-PLy_subtransaction_dealloc(PyObject *subxact)
-{
-}
-
/*
* subxact.__enter__() or subxact.enter()
*
diff --git a/src/pl/plpython/plpy_typeio.c b/src/pl/plpython/plpy_typeio.c
index 51e1d610259..1d127ae3ffe 100644
--- a/src/pl/plpython/plpy_typeio.c
+++ b/src/pl/plpython/plpy_typeio.c
@@ -723,7 +723,7 @@ PLyList_FromArray_recurse(PLyDatumToOb *elm, int *dims, int
ndim, int dim,
sublist = PLyList_FromArray_recurse(elm, dims, ndim,
dim + 1,
dataptr_p, bitmap_p, bitmask_p);
- PyList_SET_ITEM(list, i, sublist);
+ PyList_SetItem(list, i, sublist);
}
}
else
@@ -742,14 +742,14 @@ PLyList_FromArray_recurse(PLyDatumToOb *elm, int *dims,
int ndim, int dim,
if (bitmap && (*bitmap & bitmask) == 0)
{
Py_INCREF(Py_None);
- PyList_SET_ITEM(list, i, Py_None);
+ PyList_SetItem(list, i, Py_None);
}
else
{
Datum itemvalue;
itemvalue = fetch_att(dataptr, elm->typbyval,
elm->typlen);
- PyList_SET_ITEM(list, i, elm->func(elm,
itemvalue));
+ PyList_SetItem(list, i, elm->func(elm,
itemvalue));
dataptr = att_addlength_pointer(dataptr,
elm->typlen, dataptr);
dataptr = (char *) att_align_nominal(dataptr,
elm->typalign);
}
base-commit: ad40644eb8582fc1f537330b76ae7893cacf7b21
--
2.48.1
From dd07e62e041dfae67c1182226b772fe59a71f78e Mon Sep 17 00:00:00 2001
From: Peter Eisentraut <pe...@eisentraut.org>
Date: Wed, 5 Mar 2025 17:38:06 +0100
Subject: [PATCH v3 2/2] Activate Python "Limited API" in PL/Python
This allows building PL/Python against any Python 3.x version and
using another Python 3.x version at run time.
Discussion:
https://www.postgresql.org/message-id/flat/ee410de1-1e0b-4770-b125-eeefd4726...@eisentraut.org
---
src/pl/plpython/plpython.h | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/src/pl/plpython/plpython.h b/src/pl/plpython/plpython.h
index ec822577260..06fc1a5440f 100644
--- a/src/pl/plpython/plpython.h
+++ b/src/pl/plpython/plpython.h
@@ -19,6 +19,15 @@
#error Python.h must be included via plpython.h
#endif
+/*
+ * Enable Python Limited API
+ *
+ * XXX currently not enabled on MSVC because of build failures
+ */
+#if !defined(_MSC_VER)
+#define Py_LIMITED_API 0x03020000
+#endif
+
/*
* Pull in Python headers via a wrapper header, to control the scope of
* the system_header pragma therein.
--
2.48.1
