QT creator crashed on ubuntu + lxde



  • Please help my with crash investigation.

    Error output:
    bq. QXcbConnection: Failed to initialize XRandr
    Tool chain is no longer known, removing from kit "Desktop Qt 5.0.2 GCC 64bit".
    Tool chain is no longer known, removing from kit "Desktop Qt 5.0.2 GCC 64bit".
    QWidget::paintEngine: Should no longer be called
    QPainter::begin: Paint device returned engine == 0, type: 1
    QWidget::paintEngine: Should no longer be called
    QPainter::begin: Paint device returned engine == 0, type: 1
    QPainter::setClipRect: Painter not active
    QPainter::save: Painter not active
    QPainter::save: Painter not active
    QPainter::pen: Painter not active
    QPainter::setPen: Painter not active
    QPainter::setPen: Painter not active
    QPainter::restore: Unbalanced save/restore
    QPainter::setClipRegion: Painter not active
    QPainter::save: Painter not active
    QPainter::setPen: Painter not active
    QPainter::restore: Unbalanced save/restore
    QWidget::paintEngine: Should no longer be called
    QPainter::begin: Paint device returned engine == 0, type: 1
    QPainter::setPen: Painter not active
    QPainter::setPen: Painter not active
    QWidget::paintEngine: Should no longer be called
    QPainter::begin: Paint device returned engine == 0, type: 1
    QPainter::setPen: Painter not active
    QPainter::setPen: Painter not active
    QWidget::paintEngine: Should no longer be called
    QPainter::begin: Paint device returned engine == 0, type: 1
    QPainter::save: Painter not active
    QPainter::font: Painter not active
    QPainter::setFont: Painter not active
    QPainter::setPen: Painter not active
    QPainter::setPen: Painter not active
    QPainter::save: Painter not active
    QPainter::setPen: Painter not active
    QPainter::restore: Unbalanced save/restore
    QPainter::fontMetrics: Painter not active
    QPainter::translate: Painter not active
    QPainter::restore: Unbalanced save/restore
    QPainter::save: Painter not active
    QPainter::font: Painter not active
    QPainter::begin: Paint device returned engine == 0, type: 1
    QPainter::setRenderHint: Painter must be active to set rendering hints

    Call stack:

    bq. Program received signal SIGSEGV, Segmentation fault.
    0x00007ffff7511c18 in qDrawBorderPixmap(QPainter*, QRect const&, QMargins const&, QPixmap const&, QRect const&, QMargins const&, QTileRules const&, QFlagsQDrawBorderPixmap::DrawingHint) ()
    from /home/unmanner/Qt5.0.2/Tools/QtCreator/bin/../lib/qtcreator/libQt5Widgets.so.5
    (gdb) bt full
    #0 0x00007ffff7511c18 in qDrawBorderPixmap(QPainter*, QRect const&, QMargins const&, QPixmap const&, QRect const&, QMargins const&, QTileRules const&, QFlagsQDrawBorderPixmap::DrawingHint) ()
    from /home/unmanner/Qt5.0.2/Tools/QtCreator/bin/../lib/qtcreator/libQt5Widgets.so.5
    No symbol table info available.
    #1 0x00007ffff7543469 in ?? () from /home/unmanner/Qt5.0.2/Tools/QtCreator/bin/../lib/qtcreator/libQt5Widgets.so.5
    No symbol table info available.
    #2 0x00007ffff754391b in ?? () from /home/unmanner/Qt5.0.2/Tools/QtCreator/bin/../lib/qtcreator/libQt5Widgets.so.5
    No symbol table info available.
    #3 0x00007ffff7543b01 in ?? () from /home/unmanner/Qt5.0.2/Tools/QtCreator/bin/../lib/qtcreator/libQt5Widgets.so.5
    No symbol table info available.
    #4 0x00007ffff7558524 in ?? () from /home/unmanner/Qt5.0.2/Tools/QtCreator/bin/../lib/qtcreator/libQt5Widgets.so.5
    No symbol table info available.
    #5 0x00007ffff7674dfa in QToolButton::paintEvent(QPaintEvent*) ()
    from /home/unmanner/Qt5.0.2/Tools/QtCreator/bin/../lib/qtcreator/libQt5Widgets.so.5
    No symbol table info available.
    #6 0x00007fffe6e8c6a9 in ?? () from /home/unmanner/Qt5.0.2/Tools/QtCreator/lib/qtcreator/plugins/QtProject/libCore.so
    No symbol table info available.
    #7 0x00007ffff74eed30 in QWidget::event(QEvent*) ()
    from /home/unmanner/Qt5.0.2/Tools/QtCreator/bin/../lib/qtcreator/libQt5Widgets.so.5
    No symbol table info available.
    #8 0x00007ffff76754b0 in QToolButton::event(QEvent*) ()
    from /home/unmanner/Qt5.0.2/Tools/QtCreator/bin/../lib/qtcreator/libQt5Widgets.so.5
    No symbol table info available.
    #9 0x00007ffff74b85b4 in QApplicationPrivate::notify_helper(QObject*, QEvent*) ()
    from /home/unmanner/Qt5.0.2/Tools/QtCreator/bin/../lib/qtcreator/libQt5Widgets.so.5
    No symbol table info available.
    #10 0x00007ffff74bb991 in QApplication::notify(QObject*, QEvent*) ()
    from /home/unmanner/Qt5.0.2/Tools/QtCreator/bin/../lib/qtcreator/libQt5Widgets.so.5
    No symbol table info available.
    #11 0x00007ffff66157c4 in QCoreApplication::notifyInternal(QObject*, QEvent*) ()
    ---Type <return> to continue, or q <return> to quit---
    from /home/unmanner/Qt5.0.2/Tools/QtCreator/bin/../lib/qtcreator/libQt5Core.so.5



  • I see nothing in the backtrace to indicate your own code. Assuming this is not a Qt bug, and noticing that the segfault happens during UI painting, my first suggestion would be to go back to your .ui file, and make a back up.

    Then replace that QToolButton with something else.

    If the crash goes away, try replacing that something else with a new, fresh QToolButton, with default values.

    If that still does not crash, then update your new QToolButton settings to be what you want, and see what happens.

    Peter



  • Hi Peter!

    Unfortunately I unable to create my own application -- qrcreator's crash occured immediately after creator's start up. After I pressed "Done" button on the instalation wizard..



  • Oh, no. I assumed you really meant your own app, vs. Qt Creator itself.

    I doubt I can be much help. Given the crash you mentioned is right after the install, you might try restarting your machine. Seems unlikely to matter, but I have seen once or twice where it did matter (with Ubuntu).

    You might also check your system logs. I often tail logs down in /var to glean clues as to what's going on.

    Good luck with that!

    Peter



  • Thanks for your reply, I try to investigate the problem more intensive. I try to restart the mashine, and attach logsnif it does not give positive result.


  • Moderators

    Please file a bug report "here":https://bugreports.qt-project.org/ if this is with one of our packages.


Log in to reply
 

Looks like your connection to Qt Forum was lost, please wait while we try to reconnect.