Merged revisions 76764 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/branches/py3k

................
  r76764 | antoine.pitrou | 2009-12-12 20:18:27 +0100 (sam., 12 déc. 2009) | 12 lines

  Merged revisions 76763 via svnmerge from
  svn+ssh://pythondev@svn.python.org/python/trunk

  ........
    r76763 | antoine.pitrou | 2009-12-12 20:13:08 +0100 (sam., 12 déc. 2009) | 7 lines

    Issue #7466: segmentation fault when the garbage collector is called
    in the middle of populating a tuple.  Patch by Florent Xicluna.

    (note: no NEWS entry for trunk since the bug was introduced in 2.7/3.1)
  ........
................
diff --git a/Lib/test/test_tuple.py b/Lib/test/test_tuple.py
index c37adc2..53065bb 100644
--- a/Lib/test/test_tuple.py
+++ b/Lib/test/test_tuple.py
@@ -146,6 +146,9 @@
             pass
         self.check_track_dynamic(MyTuple, True)
 
+    def test_bug7466(self):
+        # Trying to untrack an unfinished tuple could crash Python
+        self._not_tracked(tuple(gc.collect() for i in range(101)))
 
 def test_main():
     support.run_unittest(TupleTest)
diff --git a/Misc/NEWS b/Misc/NEWS
index d965a11..237558d 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -12,6 +12,9 @@
 Core and Builtins
 -----------------
 
+- Issue #7466: segmentation fault when the garbage collector is called
+  in the middle of populating a tuple.  Patch by Florent Xicluna.
+
 - Issue #7419: setlocale() could crash the interpreter on Windows when called
   with invalid values.
 
diff --git a/Objects/tupleobject.c b/Objects/tupleobject.c
index 290107a..884174d 100644
--- a/Objects/tupleobject.c
+++ b/Objects/tupleobject.c
@@ -850,7 +850,8 @@
 
 	/* XXX UNREF/NEWREF interface should be more symmetrical */
 	_Py_DEC_REFTOTAL;
-	_PyObject_GC_UNTRACK(v);
+	if (_PyObject_GC_IS_TRACKED(v))
+		_PyObject_GC_UNTRACK(v);
 	_Py_ForgetReference((PyObject *) v);
 	/* DECREF items deleted by shrinkage */
 	for (i = newsize; i < oldsize; i++) {