# Breakpoint 1, _siftup (heap=0x4056b344, pos=65534) at /home/p/Python-3.4.1/Modules/_heapqmodule.c:121
# warning: Source file is more recent than executable.
# 121         Py_DECREF(PyList_GET_ITEM(heap, pos));
# (gdb) print *heap->ob_item[pos]
# $1 = {_ob_next = 0x41812058, _ob_prev = 0x831159c <refchain>, ob_refcnt = 1, ob_type = 0x4058fd1c}
# (gdb) n
# 122         PyList_SET_ITEM(heap, pos, newitem);
# (gdb) print *heap->ob_item[pos]
# Cannot access memory at address 0x3fff8
# (gdb) print *heap
# $2 = {ob_base = {ob_base = {_ob_next = 0x4059c0b4, _ob_prev = 0x405903b4, ob_refcnt = 2, ob_type = 0x830e1c0 <PyList_Type>}, 
#       ob_size = 0}, ob_item = 0x0, allocated = 0}
# (gdb) n
# 
# Program received signal SIGSEGV, Segmentation fault.
# 0x4002f150 in _siftup (heap=0x4056b344, pos=65534) at /home/p/Python-3.4.1/Modules/_heapqmodule.c:122
# 122         PyList_SET_ITEM(heap, pos, newitem);

import heapq as h
import math

N = 112233
logN = int(math.log(N)/math.log(2))
childpos = (2**logN)-2
pos = int((childpos-1)/2)

g_cnt = 0

class X():
  def __init__(self, i):
    self.i = i

  def __lt__(self, o):
    global L, g_cnt

    g_cnt += 1
    print("cnt:", g_cnt, "pos:", (self.i-1)/2)
    if g_cnt == logN-1:
      L[pos] = Y()

    return 0

class Y():
  def __del__(self):
    global L

    print("__del__ Y")
    L[childpos] = Z()

class Z():
  def __del__(self):
    global L, gZ

    print("__del__ Z")
    gZ = L[childpos]
    L[:] = []

L = [X(i) for i in range(N)]
h.heappop(L)