Bug 104853 – Qt5 RC1 globalSettings crashes in main w/o event loop

• Status: RESOLVED
• Resolution: WONTFIX
• Component: New Bugs

[That Dude]

Not sure about version I'm using default WebKit build version that comes bundled with Qt5.0 RC1

Qt 5.0 RC 1
QtCreator 2.6.1
Qt is 32 bit running on Windows7 64 bit

This code crashes in main()

#include <QWebSettings>
int main(int, char **)
{
    QWebSettings * globalSettings = QWebSettings::globalSettings();
    //qDebug() << "WebGLEnabled: " << globalSettings->testAttribute(QWebSettings::WebGLEnabled);

    return 0;
}

The example above works only after I set it on QTimer::singleShot(0, someClass, SLOT(someSlot));
i.e. requires event loop

It used to be working right from main() on previous versions e.g.
Same example works on QtCreator 2.4.1 Qt 4.8.0
on Fedora 17 64 bit where Qt suite is also 64 bit

Either fix this or document it if it's a "feature"..

[That Dude]

Same error with  Qt 5.0.0 RC2
 The program has unexpectedly finished.
 exited with code -1073741819

And C0000005 is the code for access violation.

[That Dude]

Qt debugger shows:
 +d -> <Memory access error>


WindDbg Release:

First chance exceptions are reported before any exception handling.
This exception may be expected and handled.
*** ERROR: Symbol file could not be found.  Defaulted to export symbols for C:\TEMP\zzzz\Qt5Gui.dll - 
Qt5Gui!QWindowPrivate::globalPosition+0x151:
0f73c771 8b01            mov     eax,dword ptr [ecx]  ds:002b:00000000=????????


WindDbg Debug:

(16a4.16c0): Access violation - code c0000005 (first chance)
First chance exceptions are reported before any exception handling.
This exception may be expected and handled.
*** WARNING: Unable to verify checksum for C:\PROGRAMS\Qt\500rc2\5.0.0-rc2\msvc2010\bin\Qt5Guid.dll
*** ERROR: Symbol file could not be found.  Defaulted to export symbols for C:\PROGRAMS\Qt\500rc2\5.0.0-rc2\msvc2010\bin\Qt5Guid.dll - 
Qt5Guid!QTransform::fromTranslate+0x5a659:
02413100 8b10            mov     edx,dword ptr [eax]  ds:002b:00000000=????????

[That Dude]

Qt 5.0 RC2
Seems to be working if QApplication is created before calling static
QWebSettings::globalSettings();

 i.e. this works

#include <QApplication>
#include <QDebug>
#include <QWebSettings>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    QWebSettings * globalSettings = QWebSettings::globalSettings();
    qDebug() << "WesbGLEnabled: " << globalSettings->testAttribute(QWebSettings::WebGLEnabled);

    return 0;
}
// HTH

[Brent Fulgham]

The QT port is no longer part of WebKit.