This implements the equivalent of -Wnon-pod-varargs but only for QString.
This check is disabled by default and is only useful in cases where you don't want to enable -Wnon-pod-varargs. For example on projects with thousands of benign warnings (like with MFC's CString), where you might only want to fix the QString cases.
Example
QString s = (...)
LogError("error %s", s);