Is there any danger in having a global object that uses Qt classes? Is there anything in the Qt framework that needs to be initialized before using classes such as QString or QHash?

Some customers have crashes at startup before entering main() where the QApplication object is created. For those that it happens to, it happens every time. Sending them a rebuild of the same code seems to fix the problem. Very strange. For other people it seems to never happen.

I already understand the risks and benefits of using global objects in general. I'm just wondering if Qt classes can be used in global objects since they are instantiated before the QApplication is created.