Qt Heap Corruption on Sample Provided Code - c++

Question

Just recently I've installed the Qt libraries on my computer, and as a complete novice I looked up the Qt 4.7 Getting Started guides online.
Just on the first page they provide the following code:
1 #include <QtGui>
2
3 int main(int argv, char **args)
4 {
5 QApplication app(argv, args);
6
7 QTextEdit textEdit;
8 QPushButton quitButton("Quit");
9
10 QObject::connect(&quitButton, SIGNAL(clicked()), qApp, SLOT(quit()));
11
12 QVBoxLayout layout;
13 layout.addWidget(&textEdit);
14 layout.addWidget(&quitButton);
15
16 QWidget window;
17 window.setLayout(&layout);
18
19 window.show();
20
21 return app.exec();
22 }
Simple stuff, I would suppose. Upon writing this code in Visual Studio Express 2010, building, and running, most everything works. However, when I try to close the window by means of the "Quit" button or the red-x in the top right of the displayed window (initiating "return app.exec()"), I receive the following:
A dialog box saying,
Unhandled exception at 0x77bc15de in ParticleTracker.exe: 0xC0000005: Access violation reading location 0xdf94b4b4.
And console output saying,
Critical error detected c0000374
Windows has triggered a breakpoint in ParticleTracker.exe.
This may be due to a corruption of the heap, which indicates a bug in ParticleTracker.exe or any of the DLLs it has loaded.
This may also be due to the user pressing F12 while ParticleTracker.exe has focus.
Having entered the debug-mode, I continued through the call stack while repeatedly receiving heap corruption errors.
First-chance exception at 0x77c6e6c3 in ParticleTracker.exe: 0xC0000374: A heap has been corrupted.
Unhandled exception at 0x77bc15de in ParticleTracker.exe: 0xC0000374: A heap has been corrupted.
All of the subsequent exceptions occurred at 0x77bc15de in the executable, with the memory address 0xC0000374 as a corrupted heap.
Honestly, I'm not precisely sure how I could even be getting this issue; I'm not well-versed in C++, but there appears to be nothing wrong with the code.
In the Call-Stack, the process is currently stuck at:
ParticleTracker.exe!main(int argv, char** args) Line 20 + 0x27 bytes
If I enter the disassembly the process is stuck at:
return app.exec();
00FE3831 mov esi,esp
00FE3833 call dword ptr [__imp_QApplication::exec (0FE93D0h)]
00FE3839 cmp esi,esp
00FE383B call #ILT+320(__RTC_CheckEsp) (0FE1145h)
00FE3840 mov dword ptr [ebp-150h],eax
00FE3846 mov byte ptr [ebp-4],5
00FE384A mov esi,esp
00FE384C lea ecx,[ebp-84h]
00FE3852 call dword ptr [__imp_QWidget::~QWidget (0FE9404h)]
00FE3858 cmp esi,esp
Any tips? Much appreciated. :)

Answer 1

Try this one
#include <QtGui>
int main(int argv, char **args)
{
QApplication app(argv, args);
QTextEdit *textEdit = new QTextEdit();
QPushButton *quitButton = new QPushButton("Quit");
QObject::connect(quitButton, SIGNAL(clicked()), qApp, SLOT(quit()));
QVBoxLayout *layout = new QVBoxLayout();
layout->addWidget(textEdit);
layout->addWidget(quitButton);
QWidget *window = new QWidget();
window->setLayout(layout);
window->show();
return app.exec();
}

Answer 2

It might be about ownership. When a widget is destroyed, it also takes care of its children, in your case, layouts and child widgets. QWidget destructior tries to destruct the objects, but they were allocated on the stack, and not dynamically.
Try to use dynamic allocation for QLayouts and widgets.