AppPkg/Applications/Python/Python-2.7.2/Lib/test/crashers/borrowed_ref_2.py

   1 """
   2 _PyType_Lookup() returns a borrowed reference.
   3 This attacks PyObject_GenericSetAttr().
   4
   5 NB. on my machine this crashes in 2.5 debug but not release.
   6 """
   7
   8 class A(object):
   9     pass
  10
  11 class B(object):
  12     def __del__(self):
  13         print "hi"
  14         del C.d
  15
  16 class D(object):
  17     def __set__(self, obj, value):
  18         self.hello = 42
  19
  20 class C(object):
  21     d = D()
  22
  23     def g():
  24         pass
  25
  26
  27 c = C()
  28 a = A()
  29 a.cycle = a
  30 a.other = B()
  31
  32 lst = [None] * 1000000
  33 i = 0
  34 del a
  35 while 1:
  36     c.d = 42         # segfaults in PyMethod_New(im_func=D.__set__, im_self=d)
  37     lst[i] = c.g     # consume the free list of instancemethod objects
  38     i += 1