Stack Overflow error instantiating new objects

TommyTLC

Hello everyone,

This post derives directly from my previous one. I thought I could make another one since this is a different problem and could help others in the future without having to read through the previous one.

What I am trying to achieve:
Inside the same panel I have on the left a qListWidget with different items and on the right a StackedWidget object. I would like to be able to select the items on the list and (based on which item has been selected) show the corresponding widget in the StackedWidget.

What I have done so far:
Until now I have created the qListWidget also adding the various items to it. I also created a WidgetClass per widget that I want to add to the StackedWidget. Now, thanks to the other users' tips I created a SIGNAL and SLOT system that should do the magic.

The code: (ConfigurationDialog.cpp)

ConfigurationDialog::ConfigurationDialog(QWidget* parent)
: QDialog(parent)
{
ui.setupUi(this);
setWindowFlags(Qt::WindowStaysOnTopHint);

ui.listWidget->addItem("Text1");
ui.listWidget->addItem("Text2");
ui.listWidget->addItem("Text3");
ui.listWidget->addItem("Text4");
ui.listWidget->addItem("Text5");

item1Configuration* item1 = new item1Configuration;
item2Configuration* item2 = new item2Configuration;
item3Configuration* item3 = new item3Configuration;
item4Configuration* item4 = new item4Configuration;
item5Configuration* item5 = new item5Configuration;

ui.stackedWidget->addWidget(item1);
ui.stackedWidget->addWidget(item2);
ui.stackedWidget->addWidget(item3);
ui.stackedWidget->addWidget(item4);
ui.stackedWidget->addWidget(item5);

connect(ui.listWidget, SIGNAL(itemClicked(QListWidgetItem*)),
this, SLOT(onListItemClicked(QListWidgetItem*)));
}

ConfigurationDialog::~ConfigurationDialog()
{
}

void ConfigurationDialog::onListItemClicked(QListWidgetItem* item)
{
ui.stackedWidget->setCurrentIndex(ui.listWidget->currentRow());
}

Now I think the logic is correct. The problem is that the application does not open anymore when I compile. Instead after a little bit of waiting a window opens up with the following error:

Unhandled exception at 0x00007FFD5793B866 (ntdll.dll) in Application.exe: 0xC00000FD: Stack overflow (parameters: 0x0000000000000001, 0x000000190E003FF8).

I believe this is because of the instantiation of the objects. But why is it so? How should I fix this?
Thank you in advance.

Christian Ehrlicher

Use a debugger and see where exactly it crashes.

TommyTLC

@Christian-Ehrlicher The debugger points me to this:

_CRT_SECURITYCRITICAL_ATTRIBUTE
void* __CRTDECL operator new(size_t const size)
{
for (;;)
{
if (void* const block = malloc(size)) //THIS LINE
{
return block;
}

    if (_callnewh(size) == 0)
    {
        if (size == SIZE_MAX)
        {
            __scrt_throw_std_bad_array_new_length();
        }
        else
        {
            __scrt_throw_std_bad_alloc();
        }
    }

    // The new handler was successful; try to allocate again...
}

}

Christian Ehrlicher

You should also take a look at the backtrace so you can see from where this was called.

TommyTLC

@Christian-Ehrlicher Is "backtrace" a debugging function of VisualStudio?

TommyTLC

It looks like the problem comes from the instantiation of the various objects:

item1Configuration* item1 = new item1Configuration;
item2Configuration* item2 = new item2Configuration;
item3Configuration* item3 = new item3Configuration;
item4Configuration* item4 = new item4Configuration;
item5Configuration* item5 = new item5Configuration;

When, for example, item2 is created after item1 the application freezes.

mrjj

Hi

can you show the constructor for
item2Configuration ?

and also its .h

Maybe you have some HUGE array inside or something similar as the rest of the code seems fine.

TommyTLC

@mrjj I found my mistake: I had a line instantiating the object inside its constructor. I deleted that and now it all works, thank you guys!

mrjj

@TommyTLC
Super :)