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Qt 4.8.7 Optimized code coredump at ApplicationPrivate::notify_helper

  • Hi:

    My application's main window inherites QMainwow. As soon as I call setWindowTile(), qt crashes at QApplicationPrivate::notify_helper() However, debug code does not crash.

    The following is the stack trace.
    Any suggestion will be appreciated.


    Program received signal SIGSEGV, Segmentation fault.
    0x00002aaaaac76fec in QApplicationPrivate::notify_helper (this=0x6b37c0, receiver=0x6ea5e0, e=0x7fffffffd520)
    at kernel/qapplication.cpp:4065
    4065 bool consumed = receiver->event(e);
    (gdb) where
    #0 0x00002aaaaac76fec in QApplicationPrivate::notify_helper (this=0x6b37c0, receiver=0x6ea5e0,
    e=0x7fffffffd520) at kernel/qapplication.cpp:4065
    #1 0x00002aaaaac7bc3e in QApplication::notify (this=0x7fffffffd6c0, receiver=0x6ea5e0, e=0x7fffffffd520)
    at kernel/qapplication.cpp:3961
    #2 0x00002aaaab7eb3f4 in QCoreApplication::notifyInternal (this=0x7fffffffd6c0, receiver=0x6ea5e0,
    event=0x7fffffffd520) at kernel/qcoreapplication.cpp:610
    #3 0x00002aaaaacc6d67 in sendEvent (this=0x6ea5e0, title=...)
    at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:213
    #4 QWidget::setWindowTitle (this=0x6ea5e0, title=...) at kernel/qwidget.cpp:5409
    #5 0x00000000004154dd in guMainWindow::guMainWindow (this=0x6ea5e0) at guMainWindow.cpp:25
    #6 0x0000000000414e95 in getGuMainWindow (this=<value optimized out>) at libguMainWindow.h:43
    #7 guMain::run (this=<value optimized out>) at guMain.cpp:14
    #8 0x0000000000414d94 in main (argc=<value optimized out>, argv=0x7fffffffd520) at ./src/main.cpp:9

  • Moderators

    There is no such version of Qt (4.8.7).

    When are you calling setWindowsTitle()? Please provide a bit more code.

  • It's 4.8.4

    more code. Thanks.

    @#include <string>
    #include <vector>

    #include <QMainWindow>
    #include <QMenu>
    #include <QMenuBar>
    #include <QToolBar>
    #include <QAction>
    #include "guCanvasEditor.h"
    #include "libdwFile.h"
    #include "guDWdisplay.h"
    #include "guDesignDisplay.h"
    #include "libioDspf.h"

    // forms
    #include "guFormFiles.h"

    #define STRING_SIZE 1024
    using namespace std;

    class guMainWindow : public QMainWindow


    //--- Qt stuffs

    public slots:
    void dwDisplay();
    void designDisplay();
    void displayIRdrop();
    void showViewFileForm();
    void viewFiles(vector<string> *);
    void exitOCXviewer();

    static guMainWindow *getGuMainWindow() { // Singleton
    if (_guMainWindow == NULL) { // is it the first call?
    _guMainWindow = new guMainWindow; // create sole instance
    return _guMainWindow; // address of sole instance

    bool viewPopupMenu();
    void configureStyleSheets();
    void computeDesignBBox();
    bool readXtShapes(const char *fileName);

    guMainWindow(); // declare constructor here so no one can instantiate it.
    void resizeEvent (QResizeEvent *);

    static guMainWindow *_guMainWindow;

    QMenu *_view;
    QMenu *_exit;
    guFormFiles _formViewFiles;

    QToolBar *_toolbar;
    //QMenu *_ruler;
    guCanvasEditor *_canvasEditor;
    guDesignDisplay *_designDisplay;
    // dw
    guDWdisplay *_dwDisplay;
    dwFile *_dw;

    QSize _oldSize;
    geBox _bbox; // design bounding box


    #include "libguMainWindow.h"
    #include "libdbBinPart.h"
    #include <tcl.h>
    #include <QResizeEvent>
    #include <QFileDialog>
    #include <QPixmap>
    #include <QTreeWidget>
    #include "libioViewFiles.h"
    #include <boost/algorithm/string/predicate.hpp>
    #include "libioXtQshape.h"
    #include "libutTokens.h"
    #include "libioStNetworkStitch.h"

    // sigleton, a global variable.
    guMainWindow *guMainWindow::_guMainWindow = NULL;
    guMainWindow::guMainWindow() : // QMainWindow(NULL),
    _designDisplay( NULL),
    // NOTE :
    // The two main objects in main window are _canvasEditor and _designDisplay
    setWindowTitle("OCX viewer 13.1");
    setGeometry(30,20, 900,700);


  • Moderators

    You have commented out the initialisation of the base class, so it crashes when you try running a method from that base class. Also, you are creating a singleton, but your destructor is public. It's not an error, just a unusual way of doing it.

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