title: How to copy Qt runtime DLLs to project output
body: <p>I have a simple project created in Qt Creator (installed using Qt SDK 1.1.4).  It runs just fine from within Qt Creator, but if I then browse to the output directory in Windows and double-click the EXE, I'll get an error like:</p>
  
  <pre><code>The program can't start because QtCored4.dll is missing from your computer.
  Try reinstalling the program to fix this problem.
  </code></pre>
  
  <p>That's obviously because Qt isn't in my PATH (and I don't want it to be, in case I have multiple versions of Qt on my computer), and Qt Creator / qmake didn't copy the Qt DLLs to the project output.</p>
  
  <p>What I would like to do is use qmake to copy the necessary Qt files to the project output directory - wherever it may be.  How do I do this?</p>
  
  <p>(I tried creating a custom target in qmake, but I'm not getting too far...)</p>
  
  <p><strong>UPDATE July 19, 2016:</strong>  Just to clarify, the above post was concerning Qt4.  On Qt5, you should instead look into calling <a href="http://doc.qt.io/qt-5/windows-deployment.html" rel="noreferrer"><code>windeployqt</code></a>.  This Qt5 tool will read your binary, determine which Qt5 runtime files you need, and copy them to your binary directory.  Also note that it will fix absolute paths in the Qt5::Core library that are specific to your PC - so use of this tool is basically mandatory unless you want to provide a <a href="http://doc.qt.io/qt-5/qt-conf.html" rel="noreferrer"><code>qt.conf</code></a> file yourself.</p>