Windows: Warning when call QFileDialog::getSaveFileName with a non-existing file preselected

When I call QFileDialog::getSaveFileName I get warning in console:

QWindowsDialogHelperBase<class QPlatformFileDialogHelper>::nativeDialog invoked with no native dialog present.

Example:
QFileDialog::getSaveFileName(this, tr("Save music"), tr("aaaa.wav"));

When call
QFileDialog::getSaveFileName(this, tr("Save music"));

No warning shown.

Windows 7, MSVC 2010