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connect cause exception triggered (Beginner)

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  • VRoninV Offline
    VRoninV Offline
    VRonin
    wrote on last edited by
    #5

    when you click the button, plugin in the lambda will be a dangling pointer. In debug mode some compilers set dangling pointers to NULL and this triggers your error.
    Bottom line: you are misusing the lambda

    about the delete question, when you call layout->addWidget(); the layout will take care of deleting the widgets see http://doc.qt.io/qt-5/qlayout.html#addItem

    "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
    ~Napoleon Bonaparte

    On a crusade to banish setIndexWidget() from the holy land of Qt

    1 Reply Last reply
    1
    • DumaPlusPlusD Offline
      DumaPlusPlusD Offline
      DumaPlusPlus
      wrote on last edited by
      #6

      it's strange i init them in heap store and acces them with a static list:
      in mainwindow.cpp's constructor

       for(Plugin* p : PluginCollection::get_plugins())
          {
            build_tab_from_plugin(p);
          }
      

      plugincollection.h

      namespace PluginCollection
      {
        QList<Plugin *> get_plugins()
        {
          static QList<Plugin*> list {new PastebinPlugin() };
          return list;
        }
      }
      

      should static list stay in memory (as well as allocated obj) until application closing?

      1 Reply Last reply
      0
      • DumaPlusPlusD DumaPlusPlus

        of course i have this is the complete code:

        void MainWindow::build_tab_from_plugin(Plugin *plugin)
        {
          QWidget* tab = new QWidget();
        
          QVBoxLayout* layout = new QVBoxLayout();
          QPushButton* send = new QPushButton();
          QPlainTextEdit* textBox = new QPlainTextEdit();
          QLineEdit* resultBox = new QLineEdit();
        
          connect(send,&QPushButton::clicked,[&](){ resultBox->setText(plugin->send_paste(textBox->document()->toPlainText())); });
        
          resultBox->setReadOnly(true);
          send->setText("Send paste");
        
          layout->addWidget(send);
          layout->addWidget(textBox);
          layout->addWidget(resultBox);
          tab->setLayout(layout);
        
          ui->tabWidget->addTab(tab,plugin->name());
        
        }
        

        and i benefit from this thread to ask "the objects init in heap store are delete by main window is some way or i have to manually delete them in destructor?"

        jsulmJ Offline
        jsulmJ Offline
        jsulm
        Lifetime Qt Champion
        wrote on last edited by jsulm
        #7

        @DumaPlusPlus You're passing references to local variables [&] which only exist while MainWindow::build_tab_from_plugin is being executed. Since everything you use in the lambda are pointers you can pass by value [=]. Is plugin a valid pointer?

        https://forum.qt.io/topic/113070/qt-code-of-conduct

        1 Reply Last reply
        2
        • VRoninV Offline
          VRoninV Offline
          VRonin
          wrote on last edited by VRonin
          #8

          EDIT: I WAS WRONG

          no matter how you pass thos variables [&] or [=]. when the lambda gets called all those pointers will be junk so it won't work

          "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
          ~Napoleon Bonaparte

          On a crusade to banish setIndexWidget() from the holy land of Qt

          kshegunovK 1 Reply Last reply
          0
          • VRoninV VRonin

            EDIT: I WAS WRONG

            no matter how you pass thos variables [&] or [=]. when the lambda gets called all those pointers will be junk so it won't work

            kshegunovK Offline
            kshegunovK Offline
            kshegunov
            Moderators
            wrote on last edited by
            #9

            @VRonin

            when the lambda gets called all those pointers will be junk

            Why? I think @jsulm is correct here.

            Read and abide by the Qt Code of Conduct

            1 Reply Last reply
            0
            • VRoninV Offline
              VRoninV Offline
              VRonin
              wrote on last edited by VRonin
              #10

              EDIT: I WAS WRONG

              when You call build_tab_from_plugin() all the pointers are valid and fine, then the function terminates and all pointers go out of scope. when the button is pressed, the code goes into the lambda (imagine a goto), the environment of build_tab_from_plugin is recreated but you don't know what the pointers point to right now. the lambda won't save the value of any of the pointers in its body uppon declaration

              "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
              ~Napoleon Bonaparte

              On a crusade to banish setIndexWidget() from the holy land of Qt

              kshegunovK jsulmJ 2 Replies Last reply
              0
              • DumaPlusPlusD Offline
                DumaPlusPlusD Offline
                DumaPlusPlus
                wrote on last edited by
                #11

                thanks to all.
                @jsulm resolves my problem but now i'm bit confused when do i connect SIGNAL with lambda this isn't stored somewhere? and reference used in lambda isn't an alias to a pointer (something that stay in memoery untile delete operator is called) ?

                jsulmJ 1 Reply Last reply
                0
                • VRoninV VRonin

                  EDIT: I WAS WRONG

                  when You call build_tab_from_plugin() all the pointers are valid and fine, then the function terminates and all pointers go out of scope. when the button is pressed, the code goes into the lambda (imagine a goto), the environment of build_tab_from_plugin is recreated but you don't know what the pointers point to right now. the lambda won't save the value of any of the pointers in its body uppon declaration

                  kshegunovK Offline
                  kshegunovK Offline
                  kshegunov
                  Moderators
                  wrote on last edited by kshegunov
                  #12

                  @VRonin said:

                  the lambda won't save the value of any of the pointers in its body uppon declaration

                  Sure about this? As far as I know C++11 (which isn't so well) a pointer is an automatic storage variable and is copy-captured by [=] as any other auto-storage variable.

                  the code goes into the lambda (imagine a goto), the environment of build_tab_from_plugin is recreated

                  This is very wrong way of thinking about a lambda, sorry for saying. A lambda is a typical functor (and is implemented as such).

                  Read and abide by the Qt Code of Conduct

                  1 Reply Last reply
                  0
                  • DumaPlusPlusD DumaPlusPlus

                    thanks to all.
                    @jsulm resolves my problem but now i'm bit confused when do i connect SIGNAL with lambda this isn't stored somewhere? and reference used in lambda isn't an alias to a pointer (something that stay in memoery untile delete operator is called) ?

                    jsulmJ Offline
                    jsulmJ Offline
                    jsulm
                    Lifetime Qt Champion
                    wrote on last edited by
                    #13

                    @DumaPlusPlus If you use references then then "point" to the variable. In your case they point to local variables. These local variables disappear as soon as the method finishes, so the "pointers" to them are not valid anymore - because they do not exist anymore.

                    https://forum.qt.io/topic/113070/qt-code-of-conduct

                    1 Reply Last reply
                    1
                    • VRoninV VRonin

                      EDIT: I WAS WRONG

                      when You call build_tab_from_plugin() all the pointers are valid and fine, then the function terminates and all pointers go out of scope. when the button is pressed, the code goes into the lambda (imagine a goto), the environment of build_tab_from_plugin is recreated but you don't know what the pointers point to right now. the lambda won't save the value of any of the pointers in its body uppon declaration

                      jsulmJ Offline
                      jsulmJ Offline
                      jsulm
                      Lifetime Qt Champion
                      wrote on last edited by
                      #14

                      @VRonin Sorry, but you're wrong. You can easily test this: using [&] will crash, using [=] works just fine.

                      https://forum.qt.io/topic/113070/qt-code-of-conduct

                      VRoninV 1 Reply Last reply
                      1
                      • jsulmJ jsulm

                        @VRonin Sorry, but you're wrong. You can easily test this: using [&] will crash, using [=] works just fine.

                        VRoninV Offline
                        VRoninV Offline
                        VRonin
                        wrote on last edited by VRonin
                        #15

                        @jsulm I'm really confused now as I tested it and this code works 100% fine, even with [&]. how can it be?!

                        #include <QCoreApplication>
                        #include<QDebug>
                        #include <QTimer>
                        
                        
                        int main(int argc, char *argv[]) {
                            QCoreApplication appl(argc,argv);
                            QTimer mainTimer;
                            mainTimer.setSingleShot(true);
                            {
                                QString* myString=nullptr;
                                myString=new QString("A Message");
                                QObject::connect(&mainTimer,&QTimer::timeout,[&](){qDebug() << *myString;});
                                QObject::connect(&mainTimer,&QTimer::timeout,[=](){qDebug() << *myString;});
                                // Memory leak!
                            }
                        
                            mainTimer.start(100);
                            return appl.exec();
                        }
                        
                        

                        EDIT:
                        Using MSVC2013 on Windows

                        "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
                        ~Napoleon Bonaparte

                        On a crusade to banish setIndexWidget() from the holy land of Qt

                        kshegunovK 1 Reply Last reply
                        1
                        • VRoninV VRonin

                          @jsulm I'm really confused now as I tested it and this code works 100% fine, even with [&]. how can it be?!

                          #include <QCoreApplication>
                          #include<QDebug>
                          #include <QTimer>
                          
                          
                          int main(int argc, char *argv[]) {
                              QCoreApplication appl(argc,argv);
                              QTimer mainTimer;
                              mainTimer.setSingleShot(true);
                              {
                                  QString* myString=nullptr;
                                  myString=new QString("A Message");
                                  QObject::connect(&mainTimer,&QTimer::timeout,[&](){qDebug() << *myString;});
                                  QObject::connect(&mainTimer,&QTimer::timeout,[=](){qDebug() << *myString;});
                                  // Memory leak!
                              }
                          
                              mainTimer.start(100);
                              return appl.exec();
                          }
                          
                          

                          EDIT:
                          Using MSVC2013 on Windows

                          kshegunovK Offline
                          kshegunovK Offline
                          kshegunov
                          Moderators
                          wrote on last edited by kshegunov
                          #16

                          @VRonin said:

                          QObject::connect(&mainTimer,&QTimer::timeout,[&](){qDebug() << *myString;});
                          

                          What about:

                          QObject::connect(&mainTimer,&QTimer::timeout,[&](){myString = nullptr;});
                          

                          You're capturing QString*, so you'd end up with: QString*& but you don't modify the string pointer, rather you dereference the object it's pointing to, so you'd try to output a QString & with QDebug. Also probably your compiler somewhat lax. :)

                          PS.
                          Well that's really disturbing ... I don't get any errors either. The memory will silently be overwritten. (g++ on Linux)

                          Read and abide by the Qt Code of Conduct

                          1 Reply Last reply
                          0
                          • VRoninV Offline
                            VRoninV Offline
                            VRonin
                            wrote on last edited by
                            #17

                            second test:

                            #include <QCoreApplication>
                            #include <QDebug>
                            #include <QTimer>
                            #include <QPointer>
                            
                            int main(int argc, char *argv[]) {
                                QCoreApplication appl(argc,argv);
                                QTimer mainTimer;
                                mainTimer.setSingleShot(true);
                                {
                                    QPointer<QObject> mybj;
                                    mybj =new QObject();
                                    mybj->setObjectName("A Message");
                                    QObject::connect(&mainTimer,&QTimer::timeout,[&](){qDebug() << mybj->objectName(); mybj->setObjectName("Foo"); qDebug() << mybj->objectName();});
                                    QObject::connect(&mainTimer,&QTimer::timeout,[=](){qDebug() << mybj->objectName(); mybj->setObjectName("Bar"); qDebug() << mybj->objectName();});
                                    // Memory leak!
                                }
                                {
                                    QString testString("Occuppy Stack");
                                }
                                mainTimer.start(100);
                                return appl.exec();
                            }
                            
                            

                            Still working correctly. Notice how the first output of the [=] lambda is Foo. HOW?!

                            "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
                            ~Napoleon Bonaparte

                            On a crusade to banish setIndexWidget() from the holy land of Qt

                            DumaPlusPlusD kshegunovK 2 Replies Last reply
                            0
                            • VRoninV VRonin

                              second test:

                              #include <QCoreApplication>
                              #include <QDebug>
                              #include <QTimer>
                              #include <QPointer>
                              
                              int main(int argc, char *argv[]) {
                                  QCoreApplication appl(argc,argv);
                                  QTimer mainTimer;
                                  mainTimer.setSingleShot(true);
                                  {
                                      QPointer<QObject> mybj;
                                      mybj =new QObject();
                                      mybj->setObjectName("A Message");
                                      QObject::connect(&mainTimer,&QTimer::timeout,[&](){qDebug() << mybj->objectName(); mybj->setObjectName("Foo"); qDebug() << mybj->objectName();});
                                      QObject::connect(&mainTimer,&QTimer::timeout,[=](){qDebug() << mybj->objectName(); mybj->setObjectName("Bar"); qDebug() << mybj->objectName();});
                                      // Memory leak!
                                  }
                                  {
                                      QString testString("Occuppy Stack");
                                  }
                                  mainTimer.start(100);
                                  return appl.exec();
                              }
                              
                              

                              Still working correctly. Notice how the first output of the [=] lambda is Foo. HOW?!

                              DumaPlusPlusD Offline
                              DumaPlusPlusD Offline
                              DumaPlusPlus
                              wrote on last edited by DumaPlusPlus
                              #18

                              @VRonin said:

                              second test:

                                      QObject::connect(&mainTimer,&QTimer::timeout,[&](){qDebug() << mybj->objectName(); mybj->setObjectName("Foo"); qDebug() << mybj->objectName();});
                                      QObject::connect(&mainTimer,&QTimer::timeout,[=](){qDebug() << mybj->objectName(); mybj->setObjectName("Bar"); qDebug() << mybj->objectName();});
                              
                              
                              Still working correctly. Notice how the first output of the [=] lambda is Foo. HOW?!
                              

                              should be that?
                              passing by value copy the pointer so you point to objname with modified name...right?

                              VRoninV 1 Reply Last reply
                              0
                              • DumaPlusPlusD DumaPlusPlus

                                @VRonin said:

                                second test:

                                        QObject::connect(&mainTimer,&QTimer::timeout,[&](){qDebug() << mybj->objectName(); mybj->setObjectName("Foo"); qDebug() << mybj->objectName();});
                                        QObject::connect(&mainTimer,&QTimer::timeout,[=](){qDebug() << mybj->objectName(); mybj->setObjectName("Bar"); qDebug() << mybj->objectName();});
                                
                                
                                Still working correctly. Notice how the first output of the [=] lambda is Foo. HOW?!
                                

                                should be that?
                                passing by value copy the pointer so you point to objname with modified name...right?

                                VRoninV Offline
                                VRoninV Offline
                                VRonin
                                wrote on last edited by VRonin
                                #19

                                @DumaPlusPlus The first lambda should never be executed at the creation of the second one. then when the timer times out I was expecting the first to crash or operate on invalid memory and the second to print

                                A Message
                                Bar
                                

                                While it looks like the lambda with [&] behaves exactly as the one with [=]

                                "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
                                ~Napoleon Bonaparte

                                On a crusade to banish setIndexWidget() from the holy land of Qt

                                1 Reply Last reply
                                0
                                • VRoninV VRonin

                                  second test:

                                  #include <QCoreApplication>
                                  #include <QDebug>
                                  #include <QTimer>
                                  #include <QPointer>
                                  
                                  int main(int argc, char *argv[]) {
                                      QCoreApplication appl(argc,argv);
                                      QTimer mainTimer;
                                      mainTimer.setSingleShot(true);
                                      {
                                          QPointer<QObject> mybj;
                                          mybj =new QObject();
                                          mybj->setObjectName("A Message");
                                          QObject::connect(&mainTimer,&QTimer::timeout,[&](){qDebug() << mybj->objectName(); mybj->setObjectName("Foo"); qDebug() << mybj->objectName();});
                                          QObject::connect(&mainTimer,&QTimer::timeout,[=](){qDebug() << mybj->objectName(); mybj->setObjectName("Bar"); qDebug() << mybj->objectName();});
                                          // Memory leak!
                                      }
                                      {
                                          QString testString("Occuppy Stack");
                                      }
                                      mainTimer.start(100);
                                      return appl.exec();
                                  }
                                  
                                  

                                  Still working correctly. Notice how the first output of the [=] lambda is Foo. HOW?!

                                  kshegunovK Offline
                                  kshegunovK Offline
                                  kshegunov
                                  Moderators
                                  wrote on last edited by kshegunov
                                  #20

                                  @VRonin

                                  If I haven't missed anything. my g++ doesn't open a new stack frame when it sees: { }. So in your examples (which I used) all is flat, thus myString is in main()'s stack frame, which means it doesn't go out of scope (i.e. it's not pop-ed from the stack), which ultimately means that the lambda capture is valid.

                                  Here's what I have for main() from your QString test case:

                                  # Sets up main()'s stack
                                  0x400fc2                   55                                push   %rbp
                                  0x400fc3  <+0x0001>        48 89 e5                          mov    %rsp,%rbp
                                  ...
                                  0x400fcf  <+0x000d>        48 83 ec 78                       sub    $0x78,%rsp
                                  ...
                                  # mainTimer.setSingleShot(true);
                                  0x401010  <+0x004e>        48 8d 45 80                       lea    -0x80(%rbp),%rax
                                  0x401014  <+0x0052>        be 01 00 00 00                    mov    $0x1,%esi
                                  0x401019  <+0x0057>        48 89 c7                          mov    %rax,%rdi
                                  0x40101c  <+0x005a>        e8 59 08 00 00                    callq  0x40187a <QTimer::setSingleShot(bool)>
                                  # QString * myString = nullptr;
                                  0x401021  <+0x005f>        48 c7 85 78 ff ff ff 00 00 00 00  movq   $0x0,-0x88(%rbp)
                                  # No stack frame was opened as one'd expect from a block
                                  ...
                                  # main()'s stack's being unwound
                                  0x40113c  <+0x017a>        48 83 c4 78                       add    $0x78,%rsp
                                  ...
                                  0x401149  <+0x0187>        5d                                pop    %rbp
                                  # And that was all folks, thanks for playing
                                  0x40114a  <+0x0188>        c3                                retq         
                                  

                                  As for the lambda, it doesn't make any checks. It just stores the captured address (the reference) and ultimately dereferences it when it's executed:

                                  ...
                                  # qDebug() << *myString;
                                  0x400ec3  <+0x000d>        48 8b 45 b8           mov    -0x48(%rbp),%rax    # Load QString *& from the base pointer
                                  0x400ec7  <+0x0011>        48 8b 00              mov    (%rax),%rax         # Dereference once (strip &)
                                  0x400eca  <+0x0014>        48 8b 18              mov    (%rax),%rbx         # Dereference second time i.e. (*myString)
                                  

                                  So I hope this explains how and why.

                                  Kind regards.

                                  Read and abide by the Qt Code of Conduct

                                  VRoninV 1 Reply Last reply
                                  1
                                  • kshegunovK kshegunov

                                    @VRonin

                                    If I haven't missed anything. my g++ doesn't open a new stack frame when it sees: { }. So in your examples (which I used) all is flat, thus myString is in main()'s stack frame, which means it doesn't go out of scope (i.e. it's not pop-ed from the stack), which ultimately means that the lambda capture is valid.

                                    Here's what I have for main() from your QString test case:

                                    # Sets up main()'s stack
                                    0x400fc2                   55                                push   %rbp
                                    0x400fc3  <+0x0001>        48 89 e5                          mov    %rsp,%rbp
                                    ...
                                    0x400fcf  <+0x000d>        48 83 ec 78                       sub    $0x78,%rsp
                                    ...
                                    # mainTimer.setSingleShot(true);
                                    0x401010  <+0x004e>        48 8d 45 80                       lea    -0x80(%rbp),%rax
                                    0x401014  <+0x0052>        be 01 00 00 00                    mov    $0x1,%esi
                                    0x401019  <+0x0057>        48 89 c7                          mov    %rax,%rdi
                                    0x40101c  <+0x005a>        e8 59 08 00 00                    callq  0x40187a <QTimer::setSingleShot(bool)>
                                    # QString * myString = nullptr;
                                    0x401021  <+0x005f>        48 c7 85 78 ff ff ff 00 00 00 00  movq   $0x0,-0x88(%rbp)
                                    # No stack frame was opened as one'd expect from a block
                                    ...
                                    # main()'s stack's being unwound
                                    0x40113c  <+0x017a>        48 83 c4 78                       add    $0x78,%rsp
                                    ...
                                    0x401149  <+0x0187>        5d                                pop    %rbp
                                    # And that was all folks, thanks for playing
                                    0x40114a  <+0x0188>        c3                                retq         
                                    

                                    As for the lambda, it doesn't make any checks. It just stores the captured address (the reference) and ultimately dereferences it when it's executed:

                                    ...
                                    # qDebug() << *myString;
                                    0x400ec3  <+0x000d>        48 8b 45 b8           mov    -0x48(%rbp),%rax    # Load QString *& from the base pointer
                                    0x400ec7  <+0x0011>        48 8b 00              mov    (%rax),%rax         # Dereference once (strip &)
                                    0x400eca  <+0x0014>        48 8b 18              mov    (%rax),%rbx         # Dereference second time i.e. (*myString)
                                    

                                    So I hope this explains how and why.

                                    Kind regards.

                                    VRoninV Offline
                                    VRoninV Offline
                                    VRonin
                                    wrote on last edited by
                                    #21

                                    Thanks @kshegunov now it make sense, it was just the compiler (I use MSVC btw) optimizing.
                                    This behaves as expected.

                                    #include <QCoreApplication>
                                    #include<QDebug>
                                    #include <QTimer>
                                    
                                    void makeConnections(QTimer* mainTimer ){
                                        QString* myString=nullptr;
                                        myString=new QString("A Message");
                                        QObject::connect(mainTimer,&QTimer::timeout,[&](){qDebug() << *myString;});
                                        QObject::connect(mainTimer,&QTimer::timeout,[=](){qDebug() << *myString;});
                                    }
                                    
                                    int main(int argc, char *argv[]) {
                                        QCoreApplication appl(argc,argv);
                                        QTimer mainTimer;
                                        mainTimer.setSingleShot(true);
                                        makeConnections(&mainTimer);
                                    
                                        mainTimer.start(100);
                                        return appl.exec();
                                    }
                                    
                                    

                                    I marked my previous post where I was wrong and the final answer to the topic is use [=] in the lambda instead of [&]

                                    "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
                                    ~Napoleon Bonaparte

                                    On a crusade to banish setIndexWidget() from the holy land of Qt

                                    kshegunovK 1 Reply Last reply
                                    0
                                    • VRoninV VRonin

                                      Thanks @kshegunov now it make sense, it was just the compiler (I use MSVC btw) optimizing.
                                      This behaves as expected.

                                      #include <QCoreApplication>
                                      #include<QDebug>
                                      #include <QTimer>
                                      
                                      void makeConnections(QTimer* mainTimer ){
                                          QString* myString=nullptr;
                                          myString=new QString("A Message");
                                          QObject::connect(mainTimer,&QTimer::timeout,[&](){qDebug() << *myString;});
                                          QObject::connect(mainTimer,&QTimer::timeout,[=](){qDebug() << *myString;});
                                      }
                                      
                                      int main(int argc, char *argv[]) {
                                          QCoreApplication appl(argc,argv);
                                          QTimer mainTimer;
                                          mainTimer.setSingleShot(true);
                                          makeConnections(&mainTimer);
                                      
                                          mainTimer.start(100);
                                          return appl.exec();
                                      }
                                      
                                      

                                      I marked my previous post where I was wrong and the final answer to the topic is use [=] in the lambda instead of [&]

                                      kshegunovK Offline
                                      kshegunovK Offline
                                      kshegunov
                                      Moderators
                                      wrote on last edited by kshegunov
                                      #22

                                      @VRonin

                                      Thanks @kshegunov now it make sense, it was just the compiler (I use MSVC btw) optimizing.

                                      No problem. Yes the compiler was an issue apparently, although that's some strange optimization made. Especially if you take into account we're running in debug mode, two different compilers no less. But even in release mode I'd venture to say one doesn't expect a block to just be ignored ... at least I don't.

                                      This behaves as expected.

                                      Meaning it crashes at the appropriate place? :)

                                      Read and abide by the Qt Code of Conduct

                                      VRoninV 1 Reply Last reply
                                      0
                                      • kshegunovK kshegunov

                                        @VRonin

                                        Thanks @kshegunov now it make sense, it was just the compiler (I use MSVC btw) optimizing.

                                        No problem. Yes the compiler was an issue apparently, although that's some strange optimization made. Especially if you take into account we're running in debug mode, two different compilers no less. But even in release mode I'd venture to say one doesn't expect a block to just be ignored ... at least I don't.

                                        This behaves as expected.

                                        Meaning it crashes at the appropriate place? :)

                                        VRoninV Offline
                                        VRoninV Offline
                                        VRonin
                                        wrote on last edited by
                                        #23

                                        @kshegunov said:

                                        Meaning it crashes at the appropriate place? :)

                                        Even a crash sometimes is expected behaviour ;)

                                        "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
                                        ~Napoleon Bonaparte

                                        On a crusade to banish setIndexWidget() from the holy land of Qt

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                                        • DumaPlusPlusD Offline
                                          DumaPlusPlusD Offline
                                          DumaPlusPlus
                                          wrote on last edited by
                                          #24

                                          wow very good thread i wish i will be professional like you

                                          kshegunovK 1 Reply Last reply
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