In this Qt version, obsolete functions and variables are now actually hidden in the header files if that compile definition is used.
QLayout::setMargin() -> setContentsMargins()
QDrag::start() -> QDrag::exec() with different default argument
QPalette::Background -> QPalette::Window
QMatrix -> QTransform
QPainter::drawRoundRect() -> drawRoundedRect()
QPainter::setMatrix() -> setWorldTransform()