The files in src/private/ are available under the GPL v3 (cf. LICENSE.GPL) and
were taken unmodified from the follwing files in
qt-everywhere-opensource-src-5.2.0.tar.gz:

qtbase/src/gui/painting/qbezier_p.h
qtbase/src/gui/painting/qdatabuffer_p.h
qtbase/src/gui/painting/qmath_p.h
qtbase/src/corelib/global/qnumeric_p.h
