title: Unresolved external symbol with QImage in Qt Creator
body: <p>I get linkage error in Qt Creator when I want to use QImage.</p>
  
  <pre><code>#include &lt;QCoreApplication&gt;
  #include &lt;Qt&gt;
  #include &lt;QtCore&gt;
  #include &lt;QtWidgets/QtWidgets&gt;
  #include &lt;QtGui/QImage&gt;
  
  int main(int argc, char *argv[])
  {
      QCoreApplication a(argc, argv);
  
      QImage *image = new QImage();
      // or QImage *image = new QImage("missile2.jpg");
  
      return a.exec();
  }
  </code></pre>
  
  <p>and this is project file</p>
  
  <pre><code>QT       += core
  QT       += gui
  
  TARGET = RGBLayers
  CONFIG   += console
  CONFIG   -= app_bundle
  
  TEMPLATE = app
  
  
  SOURCES += main.cpp
  </code></pre>
  
  <p>Can anyone help me what is the problem please?</p>