title: Qt5 "symbol(s) not found for architecture x86_64"
body: <p>First of all, I know there are also others posts talking about this bug but mine is a bit different I think.</p>
  
  <p>I've got a Qt project with this pro file :</p>
  
  <pre><code>QT       += core
  QT       += network
  QT       -= gui
  
  TARGET = QDownloaderCLI
  
  CONFIG   += console
  CONFIG   -= app_bundle
  
  
  TEMPLATE ...
  </code></pre>
  
  <p>I tried with <code>CONFIG -= X86_64</code> but nothing change.</p>
  
  <p>Searching on the web I discover something strange, I've got a .h file with a public slot with his implementation in a .cpp file :</p>
  
  <pre><code>public slots:
      void stateChanged(int state);
  </code></pre>
  
  <p>With this I've got the error message but if I comment <code>void stateChanged(int state);</code> in .h and .cpp it works.</p>
  
  <p>How do I fix this ?</p>
  
  <p>I also have warnings : </p>
  
  <pre><code>directory not found for option '-F/Applications/Qt//5.1.0/clang_64/qtbase/lib'
  </code></pre>
  
  <p>and</p>
  
  <pre><code>"This version of OS X is unsupported" [-W#warnings]
  </code></pre>
  
  <p>I also tried "Run qMake" but I've got warnings too :</p>
  
  <pre><code>No .qmake.cache is present. This significantly slows down qmake with this makespec.
  Call 'cache()' in the top-level project file to rectify this problem.
  </code></pre>
  
  <p>I'm on Mac OS X 10.8.4 with Qt 5.1.0</p>
  
  <p>Code of my .h file :</p>
  
  <pre><code>#ifndef DOWNLOADER_H
  #define DOWNLOADER_H
  
  #include &lt;QObject&gt;
  #include &lt;QDebug&gt;
  #include &lt;QFile&gt;
  // In Qt 5 no more QHttp
  #include &lt;QNetworkAccessManager&gt;
  
  class downloader : public QObject
  {
      Q_OBJECT
  public:
      explicit downloader(QObject *parent = 0);
      void doDownload();
  
  signals:
  
  public slots:
      void stateChanged(int state);
  
  private:
     QNetworkAccessManager *http;
  
  };
  
  #endif // DOWNLOADER_H
  </code></pre>