segmentation fault

Hello,

I use the yade 1.07.0 and ubuntu 14.04. after I run my iteration about 60000 times, it shows a segmentation fault. I have read some related questions, it said user need to open a bug. I don't know what means "open a bug", i follow the instruction from https://www.yade-dem.org/doc/user.html#crashes, after I done 2 steps.

Yade [1]: import os,signal
Yade [2]: os.kill(os.getpid(),signal.SIGSEGV)

it shows segmentation fault again.

I also read that install a daily version is a solution but after 3 lines
sudo add-apt-repository ppa:yade-pkg/stable
sudo apt-get update
sudo apt-get install yade-stable

it said "E: Unable to locate package yade-stable"

what happens?
this is my script.
from yade import pack
from yade import timing
from yade import qt
import gts, locale

idPFA=O.materials.append(FrictMat(density=100,young=5e6,poisson=.32,frictionAngle=.1,label="PFA"))
idSOIL=O.materials.append(FrictMat(density=500,young=5e6,poisson=.32,frictionAngle=.53,label="soil"))
idFEN=O.materials.append(FrictMat(density=800,young=8e6,poisson=.32,frictionAngle=.53,label="fence"))

surf=gts.read(open('sphere.gts'))
surf2=gts.read(open('slope.gts'))
surf3=gts.read(open('fence.gts'))

if surf.is_closed():
        pred=pack.inGtsSurface(surf)
        aabb=pred.aabb()
        dim0=aabb[1][0]-aabb[0][0]; radius=dim0/60. # get some characteristic dimension, use it for radius
        O.bodies.append(pack.regularHexa(pred,radius=radius,gap=radius/4.,material=idPFA))

O.bodies.append(pack.gtsSurface2Facets(surf2,wire=True,material="soil"))
O.bodies.append(pack.gtsSurface2Facets(surf3,wire=True,material="fence"))

O.engines=[
         ForceResetter(),
         InsertionSortCollider([Bo1_Sphere_Aabb(),Bo1_Facet_Aabb()],label='collider'),
         InteractionLoop(
                        [Ig2_Sphere_Sphere_L3Geom(),Ig2_Facet_Sphere_L3Geom()],
   [Ip2_FrictMat_FrictMat_FrictPhys()],
   [Law2_L3Geom_FrictPhys_ElPerfPl()],
   ),
   NewtonIntegrator(damping=0.015,gravity=[0,0,-9.81]),
   PyRunner(iterPeriod=5000000,command='timing.stats(); O.pause();'),
   VTKRecorder(iterPeriod=15000,recorders=['all'],fileName='3d-vtk-'),

]
O.dt=0.05*PWaveTimeStep()
O.saveTmp()