title: Qt (custom build) doesn't use system style on Ubuntu
body: <p>I have an app I'm developing with Qt 5.4.2 on Ubuntu 12.04. I had been using the binaries that came with the Qt Creator download, but needed to customize some things, so I built the Qt binaries from source, still version 5.4.2.</p>
  
  <p>Here's the issue I encountered: the gui no longer uses the native style. The left-hand gui is what I want. The right-hand gui is what I get with my custom-build Qt libraries.</p>
  
  <p><img src="https://i.stack.imgur.com/kEjIP.png" alt="enter image description here"></p>
  
  <p>Here's the command I used for the Qt build configuration:</p>
  
  <pre><code>./configure -release -nomake examples -no-openssl -no-opengl -no-sql-sqlite -no-openvg -no-icu -no-libjpeg -platform linux-g++ -qt-xcb
  </code></pre>
  
  <p><em>Important to note:</em> The Qt Designer app also has the same non-native gui styling with my custom build, so it's the library's fault and not my app's fault. And since both are using the same version of Qt, I can figure that it's probably an issue with my system or my configuration, and not with Qt itself.</p>