[3.14] gh-132775: Always Set __builtins__ In _PyFunction_FromXIData() (gh-134794)

miss-islington · ericsnowcurrently · web-flow · commit 6493395f4b69 · 2025-05-27T16:07:44.000Z
This is a small follow-up to gh-133481. There's a corner case in the behavior of PyImport_ImportModuleAttrString(), where it expects __builtins__ to be set if __globals__ is set. (cherry picked from commit 9b5e800, AKA gh-134758) Co-authored-by: Eric Snow <ericsnowcurrently@gmail.com>
diff --git a/Python/crossinterp_data_lookup.h b/Python/crossinterp_data_lookup.h
@@ -701,6 +701,14 @@ _PyFunction_FromXIData(_PyXIData_t *xidata)
         Py_DECREF(code);
         return NULL;
     }
+    PyThreadState *tstate = _PyThreadState_GET();
+    if (PyDict_SetItem(globals, &_Py_ID(__builtins__),
+                       tstate->interp->builtins) < 0)
+    {
+        Py_DECREF(code);
+        Py_DECREF(globals);
+        return NULL;
+    }
     PyObject *func = PyFunction_New(code, globals);
     Py_DECREF(code);
     Py_DECREF(globals);
