hello,
i want to know how to debug with Qt because i want to execute this code but it gives an error.
imageViewer.h
Qt Code: 
  1. #ifndef IMAGEVIEWER_H
  2. #define IMAGEVIEWER_H
  3. #include<QtWidgets>
  4.  
  5. class ImageViewer : public QMainWindow
  6. {
  7.     Q_OBJECT
  8. public:
  9.     ImageViewer();
  10. public slots:
  11.     void ouvrir();
  12. private:
  13.     QLabel *label;
  14.     QImage *image;
  15.     QVBoxLayout *layout;
  16. };
  17.  
  18. #endif // IMAGEVIEWER_H
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imageViewer.cpp
Qt Code: 
  1. #include "imageviewer.h"
  2.  
  3. ImageViewer::ImageViewer(): QMainWindow()
  4. {
  5.     label = new QLabel(this);
  6.  
  7.     label->move(100,100);
  8.     label->setFixedSize(500,500);
  9.     layout = new QVBoxLayout(this);
  10.     layout->addWidget(label);
  11.     this->setLayout(layout);
  12.     QMenu *fichier = menuBar()->addMenu("Fichier");
  13.     QMenu *edition = menuBar()->addMenu("Edition");
  14.  
  15.     QAction *ouvrir = new QAction("Ouvrir",this);
  16.     fichier->addAction(ouvrir);
  17.     connect(ouvrir,SIGNAL(triggered(bool)),this,SLOT(ouvrir()));
  18.  
  19.  
  20.  
  21. }
  22.  
  23. void ImageViewer::ouvrir()
  24. {
  25.     QString nomFichier = QFileDialog::getOpenFileName(this,"Open file", "C://");
  26.     image = new QImage(nomFichier);
  27.     label->setPixmap(QPixmap::fromImage(QImage(nomFichier)));
  28. }
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and the error is
cannot open output file debug\app.exe: Permission denied
error: ld returned 1 exit status

Thank you.