QMenu and addAction problem

Hello there !
What is wrong with this code, i am confused:mad:

Code:

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void QNotePad::createMenus()
{
    QMenu *fileMenu = menuBar()->addMenu("File");
    m_newFileAction = fileMenu->addAction("New");
}

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this function belongs to my MainWindow but when i run this code Qt says :

The program has unexpectedly finished.
/home/saeed/Documents/Qt Project/QNotePad-build-desktop/QNotePad exited with code 0

m_newFileAction is a QAction * data member.
Thanks

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Added after 28 minutes:

i found it !;)
i had forgotten to insert QT+= gui core in my .pro file when i create new empty project