[3.12] gh-109894: Fix initialization of static MemoryError in subinterpreter (gh-110911) (gh-111238)

Fixes GH-109894

* set `interp.static_objects.last_resort_memory_error.args` to empty tuple to avoid crash on `PyErr_Display()` call
* allow `_PyExc_InitGlobalObjects()` to be called on subinterpreter init

---------

(cherry picked from commit 47d3e2e)

Co-authored-by: Radislav Chugunov <[email protected]>
Co-authored-by: blurb-it[bot] <43283697+blurb-it[bot]@users.noreply.github.com>

Author: 3 people

Include/internal/pycore_runtime_init.h

@@ -119,6 +119,7 @@ extern PyTypeObject _PyExc_MemoryError;
                 }, \
                 .last_resort_memory_error = { \
                     _PyObject_HEAD_INIT(&_PyExc_MemoryError) \
+                    .args = (PyObject*)&_Py_SINGLETON(tuple_empty) \
                 }, \
             }, \
         }, \

Lib/test/test_exceptions.py

@@ -1785,6 +1785,20 @@ class TestException(MemoryError):
 
             gc_collect()
 
+    def test_memory_error_in_subinterp(self):
+        # gh-109894: subinterpreters shouldn't count on last resort memory error
+        # when MemoryError is raised through PyErr_NoMemory() call,
+        # and should preallocate memory errors as does the main interpreter.
+        # interp.static_objects.last_resort_memory_error.args
+        # should be initialized to empty tuple to avoid crash on attempt to print it.
+        code = f"""if 1:
+            import _testcapi
+            _testcapi.run_in_subinterp(\"[0]*{sys.maxsize}\")
+            exit(0)
+        """
+        rc, _, err = script_helper.assert_python_ok("-c", code)
+        self.assertIn(b'MemoryError', err)
+
 
 class NameErrorTests(unittest.TestCase):
     def test_name_error_has_name(self):

Misc/NEWS.d/next/Core and Builtins/2023-10-15-22-18-45.gh-issue-109894.UAmo06.rst

@@ -0,0 +1 @@
+Fixed crash due to improperly initialized static :exc:`MemoryError` in subinterpreter.

Objects/exceptions.c

@@ -3701,10 +3701,6 @@ _PyExc_FiniTypes(PyInterpreterState *interp)
 PyStatus
 _PyExc_InitGlobalObjects(PyInterpreterState *interp)
 {
-    if (!_Py_IsMainInterpreter(interp)) {
-        return _PyStatus_OK();
-    }
-
     if (preallocate_memerrors() < 0) {
         return _PyStatus_NO_MEMORY();
     }