bpo-45061: Detect refcount bug on empty tuple singleton (GH-28503)

Detect refcount bugs in C extensions when the empty tuple singleton
is destroyed by mistake.

Add the _Py_FatalRefcountErrorFunc() function.

1 files changed, 6 insertions, 0 deletions

diff --git a/Include/internal/pycore_pyerrors.h b/Include/internal/pycore_pyerrors.h
index a5e97fe23fb..0f4d41c7e0b 100644
--- a/Include/internal/pycore_pyerrors.h
+++ b/Include/internal/pycore_pyerrors.h
@@ -90,6 +90,12 @@ extern PyObject* _Py_Offer_Suggestions(PyObject* exception);
 PyAPI_FUNC(Py_ssize_t) _Py_UTF8_Edit_Cost(PyObject *str_a, PyObject *str_b,
                                           Py_ssize_t max_cost);
 
+PyAPI_FUNC(void) _Py_NO_RETURN _Py_FatalRefcountErrorFunc(
+    const char *func,
+    const char *message);
+
+#define _Py_FatalRefcountError(message) _Py_FatalRefcountErrorFunc(__func__, message)
+
 #ifdef __cplusplus
 }
 #endif