What's wrong??

[dreamer]

I have a Segmentation-fault problem in my program but i don't understand the why(perhaps is a Qt bug!!)

This is my debug:

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread -1226594624 (LWP 7388)]
QGraphicsItem::setPos (this=0xffece9d8, pos=@0xbf9c2f60)
    at graphicsview/qgraphicsitem.cpp:2053
2053    graphicsview/qgraphicsitem.cpp: No such file or directory.
        in graphicsview/qgraphicsitem.cpp
(gdb) bt
#0  QGraphicsItem::setPos (this=0xffece9d8, pos=@0xbf9c2f60)
    at graphicsview/qgraphicsitem.cpp:2053
#1  0x08096f11 in MarginDialog::on_spinBox_3_valueChanged ()
#2  0x080a3dfb in MarginDialog::qt_metacall ()
#3  0xb7312131 in QMetaObject::activate (sender=0x8294fb8,
    from_signal_index=<value optimized out>, to_signal_index=34,
    argv=<value optimized out>) at kernel/qobject.cpp:3001
#4  0xb73127c2 in QMetaObject::activate (sender=0x8294fb8, m=0xb7f2d04c,
    local_signal_index=0, argv=0xbf9c305c) at kernel/qobject.cpp:3071
#5  0xb7d2c623 in QSpinBox::valueChanged (this=0x8294fb8, _t1=10)
    at .moc/release-shared/moc_qspinbox.cpp:132
#6  0xb7b36519 in QSpinBoxPrivate::emitSignals (this=0x8295088,
    ep=EmitIfChanged, old=@0xbf9c30e8) at widgets/qspinbox.cpp:951
#7  0xb7a8aa0c in QAbstractSpinBoxPrivate::setValue (this=0x8295088,
    val=@0xbf9c3140, ep=EmitIfChanged, doUpdate=true)
    at widgets/qabstractspinbox.cpp:1645
#8  0xb7b34b4e in QSpinBox::setValue (this=0x8294fb8, value=10)
    at widgets/qspinbox.cpp:255
#9  0x08096e9e in MarginDialog::resetSpinBox ()
#10 0x08076f7a in XmlGenerator::parseFile ()
#11 0x0805ecf7 in MainWindow::on_actionOpen_triggered ()
#12 0x080a2f5d in MainWindow::qt_metacall ()
#13 0xb7312131 in QMetaObject::activate (sender=0x813c3b0,

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread -1226594624 (LWP 7388)]
QGraphicsItem::setPos (this=0xffece9d8, pos=@0xbf9c2f60)
    at graphicsview/qgraphicsitem.cpp:2053
2053    graphicsview/qgraphicsitem.cpp: No such file or directory.
        in graphicsview/qgraphicsitem.cpp
(gdb) bt
#0  QGraphicsItem::setPos (this=0xffece9d8, pos=@0xbf9c2f60)
    at graphicsview/qgraphicsitem.cpp:2053
#1  0x08096f11 in MarginDialog::on_spinBox_3_valueChanged ()
#2  0x080a3dfb in MarginDialog::qt_metacall ()
#3  0xb7312131 in QMetaObject::activate (sender=0x8294fb8,
    from_signal_index=<value optimized out>, to_signal_index=34,
    argv=<value optimized out>) at kernel/qobject.cpp:3001
#4  0xb73127c2 in QMetaObject::activate (sender=0x8294fb8, m=0xb7f2d04c,
    local_signal_index=0, argv=0xbf9c305c) at kernel/qobject.cpp:3071
#5  0xb7d2c623 in QSpinBox::valueChanged (this=0x8294fb8, _t1=10)
    at .moc/release-shared/moc_qspinbox.cpp:132
#6  0xb7b36519 in QSpinBoxPrivate::emitSignals (this=0x8295088,
    ep=EmitIfChanged, old=@0xbf9c30e8) at widgets/qspinbox.cpp:951
#7  0xb7a8aa0c in QAbstractSpinBoxPrivate::setValue (this=0x8295088,
    val=@0xbf9c3140, ep=EmitIfChanged, doUpdate=true)
    at widgets/qabstractspinbox.cpp:1645
#8  0xb7b34b4e in QSpinBox::setValue (this=0x8294fb8, value=10)
    at widgets/qspinbox.cpp:255
#9  0x08096e9e in MarginDialog::resetSpinBox ()
#10 0x08076f7a in XmlGenerator::parseFile ()
#11 0x0805ecf7 in MainWindow::on_actionOpen_triggered ()
#12 0x080a2f5d in MainWindow::qt_metacall ()
#13 0xb7312131 in QMetaObject::activate (sender=0x813c3b0,

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I don't see any 0x0 value.............................

[jacek]

What happens in on_spinBox_3_valueChanged()? Do you access some graphics item through a pointer? If yes, are you sure that this pointer is initialized?

[dreamer]

What happens in on_spinBox_3_valueChanged()? Do you access some graphics item through a pointer? If yes, are you sure that this pointer is initialized?

yes, i find the problem(in on_spinBox_3_valueChanged() i used an unnitializer pointer.....)