From bbe46d63ee9b624c011b4fe50978e2e7fa7cf82e Mon Sep 17 00:00:00 2001
From: Amaury Forgeot d'Arc <amauryfa@gmail.com>
Date: Mon, 12 Sep 2011 21:03:36 +0200
Subject: [PATCH] Issue #12483: ctypes: Fix a crash when the destruction of a
 callback object triggers the garbage collector.

---
 Lib/ctypes/test/test_callbacks.py | 8 ++++++++
 Misc/NEWS                         | 3 +++
 Modules/_ctypes/callbacks.c       | 1 +
 3 files changed, 12 insertions(+)

diff --git a/Lib/ctypes/test/test_callbacks.py b/Lib/ctypes/test/test_callbacks.py
index 8801ccd1069..c7207eab9d2 100644
--- a/Lib/ctypes/test/test_callbacks.py
+++ b/Lib/ctypes/test/test_callbacks.py
@@ -134,6 +134,14 @@ class Callbacks(unittest.TestCase):
                 if isinstance(x, X)]
         self.assertEqual(len(live), 0)
 
+    def test_issue12483(self):
+        import gc
+        class Nasty:
+            def __del__(self):
+                gc.collect()
+        CFUNCTYPE(None)(lambda x=Nasty(): None)
+        
+
 try:
     WINFUNCTYPE
 except NameError:
diff --git a/Misc/NEWS b/Misc/NEWS
index d9e8f4b3b08..d52156d417c 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -65,6 +65,9 @@ Tests
 Extension Modules
 -----------------
  
+- Issue #12483: ctypes: Fix a crash when the destruction of a callback
+  object triggers the garbage collector.
+
 - Issue #12950: Fix passing file descriptors in multiprocessing, under
   OpenIndiana/Illumos.
 
diff --git a/Modules/_ctypes/callbacks.c b/Modules/_ctypes/callbacks.c
index d23509fbe2c..34c46ad7a7e 100644
--- a/Modules/_ctypes/callbacks.c
+++ b/Modules/_ctypes/callbacks.c
@@ -13,6 +13,7 @@ static void
 CThunkObject_dealloc(PyObject *_self)
 {
     CThunkObject *self = (CThunkObject *)_self;
+    PyObject_GC_UnTrack(self);
     Py_XDECREF(self->converters);
     Py_XDECREF(self->callable);
     Py_XDECREF(self->restype);