title: qmake does not add widgets
body: <p>i have a simple program.  my program is:</p>
  
  <pre><code> #include &lt;QApplication&gt;
   #include &lt;QLabel&gt;
  
   int main(int argc, char *argv[])
  {
   int rc ; 
      QApplication app(argc, argv);  
       QLabel *label = new QLabel("Hello Qt!");
      label-&gt;show();
       rc = app.exec();
       return(rc) ;
  }
  </code></pre>
  
  <p>i want to compile and build this code in command line.
  i have installed qt and mingw.</p>
  
  <p>first my command is:</p>
  
  <pre><code>  qmake -project
  </code></pre>
  
  <p>then i give  this command.</p>
  
  <pre><code>  qmake
  </code></pre>
  
  <p>then qmake creates .pro file which is:</p>
  
  <pre><code> TEMPLATE = app
   TARGET = HELLO
   INCLUDEPATH += .
  
   # Input
   SOURCES += hello.cpp
  </code></pre>
  
  <p>i think this file must inclue ' QT += widgets' but it doesnt. i dont know why.
  finally, i call mingw make</p>
  
  <p>and it gives error.</p>
  
  <p>when i add .pro file  QT += widgets then call mingw-make, it works and creates .exe file.</p>
  
  <p>then my question is that, why qmake automatically add  <code>QT += widgets</code> , how can i do this? i dont want to add manually.</p>