# Program received signal SIGSEGV, Segmentation fault.
# 0x4068565c in xmlparser_setevents (self=0x4064b13c, args=([], [<S2 at remote 0x4064b0e4>]))
#     at /home/p/Python-3.4.1/Modules/_elementtree.c:3562
# 3562            if (PyUnicode_Check(event_name_obj)) {
# (gdb) print *event_name_obj
# $6 = {_ob_next = 0xdbdbdbdb, _ob_prev = 0xdbdbdbdb, ob_refcnt = -606348325, ob_type = 0xdbdbdbdb}
# 
# 
# "event_name_obj" is deleted inside a custom destructor. Use after free.

import xml.etree.ElementTree as et

class S1(str):
  def __del__(self):
    global parser

    print("__del__ 1")
    parser._setevents([], [S3("end")])

class S2(str):
  def __del__(self):
    print("__del__ 2")

class S3(str):
  def __del__(self):
    global L

    print("__del__ 3")
    del L[1]

class X:
  pass

L = [S2("end"), X()]
parser = et.XMLParser(target=et.TreeBuilder())
parser._setevents([], [S1("end")])
parser._setevents([], L)