Application: knetwalk (3.0.1)
KDE Platform Version: 4.10.00 (Compiled from sources)
Qt Version: 4.8.4
Operating System: Linux 3.6.11-gentoo x86_64
Distribution: "Gentoo Base System release 2.1"

-- Information about the crash:
- What I was doing when the application crashed:
KNetWalk hung up on clicking "New", consuming one cpu. I made it crash by manually sending SIGSEGV with the kill command to the process. 

- Custom settings of the application:
Difficulty was set to easy.

The bug can be reproduced by repeatedly clicking on New. I tried it several times and most times it took less than 100 new games to run into this bug.

The crash can be reproduced some of the time.

-- Backtrace:
Application: KNetWalk (knetwalk), signal: Segmentation fault
Using host libthread_db library "/lib64/libthread_db.so.1".
[KCrash Handler]
#6  AbstractGrid::addRandomCable (this=0x2263810, list=...) at /var/tmp/portage/kde-base/knetwalk-4.10.0/work/knetwalk-4.10.0/src/abstractgrid.cpp:251
#7  0x0000000000415433 in AbstractGrid::createGrid (this=0x2263810) at /var/tmp/portage/kde-base/knetwalk-4.10.0/work/knetwalk-4.10.0/src/abstractgrid.cpp:227
#8  0x0000000000416370 in AbstractGrid::initializeGrid (this=0x2263810, width=5, height=5, wrapping=NotWrapped) at /var/tmp/portage/kde-base/knetwalk-4.10.0/work/knetwalk-4.10.0/src/abstractgrid.cpp:149
#9  0x0000000000410858 in FieldItem::initField (this=0x22637f0, width=<optimized out>, height=<optimized out>, w=<optimized out>) at /var/tmp/portage/kde-base/knetwalk-4.10.0/work/knetwalk-4.10.0/src/fielditem.cpp:41
#10 0x00000000004115ed in KNetWalkScene::startNewGame (this=0x2260330, width=<optimized out>, height=<optimized out>, w=<optimized out>) at /var/tmp/portage/kde-base/knetwalk-4.10.0/work/knetwalk-4.10.0/src/scene.cpp:92
#11 0x00000000004128e2 in MainWindow::startNewGame (this=0x2263690) at /var/tmp/portage/kde-base/knetwalk-4.10.0/work/knetwalk-4.10.0/src/mainwindow.cpp:175
#12 0x00007f8ce3a930c1 in QMetaObject::activate (sender=0x2547810, m=<optimized out>, local_signal_index=<optimized out>, argv=0x7fffa4eb7eb0) at kernel/qobject.cpp:3539
#13 0x00007f8ce44dc012 in QAction::triggered (this=<optimized out>, _t1=false) at .moc/release-shared/moc_qaction.cpp:277
#14 0x00007f8ce44dc1d7 in QAction::activate (this=0x2547810, event=<optimized out>) at kernel/qaction.cpp:1257
#15 0x00007f8ce489135f in QAbstractButtonPrivate::click (this=0x266f540) at widgets/qabstractbutton.cpp:530
#16 0x00007f8ce48915cc in QAbstractButton::mouseReleaseEvent (this=0x265e8a0, e=0x7fffa4eb8910) at widgets/qabstractbutton.cpp:1123
#17 0x00007f8ce494e36a in QToolButton::mouseReleaseEvent (this=<optimized out>, e=<optimized out>) at widgets/qtoolbutton.cpp:718
#18 0x00007f8ce453357b in QWidget::event (this=0x265e8a0, event=0x7fffa4eb8910) at kernel/qwidget.cpp:8375
#19 0x00007f8ce44e2534 in notify_helper (e=0x7fffa4eb8910, receiver=0x265e8a0, this=0x20f4eb0) at kernel/qapplication.cpp:4562
#20 QApplicationPrivate::notify_helper (this=0x20f4eb0, receiver=0x265e8a0, e=0x7fffa4eb8910) at kernel/qapplication.cpp:4534
#21 0x00007f8ce44e7b5b in QApplication::notify (this=<optimized out>, receiver=0x265e8a0, e=0x7fffa4eb8910) at kernel/qapplication.cpp:4105
#22 0x00007f8ce56f0148 in KApplication::notify (this=0x7fffa4eb9450, receiver=0x265e8a0, event=0x7fffa4eb8910) at /var/tmp/portage/kde-base/kdelibs-4.10.0/work/kdelibs-4.10.0/kdeui/kernel/kapplication.cpp:311
#23 0x00007f8ce3a7ef8b in QCoreApplication::notifyInternal (this=0x7fffa4eb9450, receiver=0x265e8a0, event=0x7fffa4eb8910) at kernel/qcoreapplication.cpp:946
#24 0x00007f8ce44e34c2 in sendEvent (event=<optimized out>, receiver=<optimized out>) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:231
#25 QApplicationPrivate::sendMouseEvent (receiver=0x265e8a0, event=0x7fffa4eb8910, alienWidget=0x265e8a0, nativeWidget=0x2661e60, buttonDown=0x265e8a0, lastMouseReceiver=..., spontaneous=true) at kernel/qapplication.cpp:3173
#26 0x00007f8ce455fe3f in QETWidget::translateMouseEvent (this=0x2661e60, event=<optimized out>) at kernel/qapplication_x11.cpp:4516
#27 0x00007f8ce455ec52 in QApplication::x11ProcessEvent (this=0x7fffa4eb9450, event=0x7fffa4eb9030) at kernel/qapplication_x11.cpp:3639
#28 0x00007f8ce4586362 in x11EventSourceDispatch (s=0x20f5900, callback=0x0, user_data=0x0) at kernel/qguieventdispatcher_glib.cpp:146
#29 0x00007f8cdfc71bf2 in g_main_dispatch (context=0x20f1b40) at gmain.c:2539
#30 g_main_context_dispatch (context=0x20f1b40) at gmain.c:3075
#31 0x00007f8cdfc71f35 in g_main_context_iterate (dispatch=1, block=<optimized out>, context=0x20f1b40, self=<optimized out>) at gmain.c:3146
#32 g_main_context_iterate (context=0x20f1b40, block=<optimized out>, dispatch=1, self=<optimized out>) at gmain.c:3083
#33 0x00007f8cdfc71fec in g_main_context_iteration (context=0x20f1b40, may_block=1) at gmain.c:3207
#34 0x00007f8ce3aae28e in QEventDispatcherGlib::processEvents (this=0x20d6540, flags=...) at kernel/qeventdispatcher_glib.cpp:426
#35 0x00007f8ce4586026 in QGuiEventDispatcherGlib::processEvents (this=<optimized out>, flags=...) at kernel/qguieventdispatcher_glib.cpp:204
#36 0x00007f8ce3a7da32 in QEventLoop::processEvents (this=<optimized out>, flags=...) at kernel/qeventloop.cpp:149
#37 0x00007f8ce3a7dcb7 in QEventLoop::exec (this=0x7fffa4eb93d0, flags=...) at kernel/qeventloop.cpp:204
#38 0x00007f8ce3a82ba5 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1218
#39 0x000000000040dc7b in main (argc=3, argv=0x7fffa4eb9788) at /var/tmp/portage/kde-base/knetwalk-4.10.0/work/knetwalk-4.10.0/src/main.cpp:68

Reported using DrKonqi