I've encountered a problem in building a simple application using Qt 4.8.4 (built statically) and Linux Mint 14.

Qt Code:
  1. #include <QApplication>
  2. #include <QLabel>
  4. int main(int argc, char *argv[])
  5. {
  6. QApplication a(argc, argv);
  8. QLabel label("label");
  9. label.setAttribute(Qt::WA_TranslucentBackground);
  10. label.setFixedSize(400,400);
  11. label.show();
  13. return a.exec();
  14. }
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In my linux distribution I've enabled compositing and I've installed Qt Creator and the previous version of Qt libraries (4.8.3) from the repositories.
Using this version I don't have any problem with transparency, the label is shown as expected, but if I want to build statically my application using the 4.8.4 version, the background color is black.

I've tried to change the style using QApplication::setStyle(...) or using another Qt libraries version (4.8.2) built statically, but I was not able to solve the problem.
If anybody has any idea, please help me.
Thanks in advance