better PyObject_HEAD size calculation

fixes infinite loop on Python 3.6 32-bit

diff --git a/CHANGES.rst b/CHANGES.rst
index 9635fc5588264b9276d3e389b5c53843a7b0cb50..aee6ad3a3e9193b2e542b1fe7d9b3da296a47a8c 100644 (file)
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -10,6 +10,8 @@ Unreleased
     :func:`contextfunction`. :issue:`1145`
 -   Update ``wordcount`` filter to trigger :class:`Undefined` methods
     by wrapping the input in :func:`soft_unicode`. :pr:`1160`
+-   Fix a hang when displaying tracebacks on Python 32-bit.
+    :issue:`1162`
 
 
 Version 2.11.1

diff --git a/src/jinja2/debug.py b/src/jinja2/debug.py
index d2c5a06bf6c1b17087a2663d84b2b735766f4a34..5d8aec31d05dab0b01b192b9dfe74f2656dc3077 100644 (file)
--- a/src/jinja2/debug.py
+++ b/src/jinja2/debug.py
@@ -245,10 +245,7 @@ else:
     class _CTraceback(ctypes.Structure):
         _fields_ = [
             # Extra PyObject slots when compiled with Py_TRACE_REFS.
-            (
-                "PyObject_HEAD",
-                ctypes.c_byte * (32 if hasattr(sys, "getobjects") else 16),
-            ),
+            ("PyObject_HEAD", ctypes.c_byte * object().__sizeof__()),
             # Only care about tb_next as an object, not a traceback.
             ("tb_next", ctypes.py_object),
         ]