QtVersionOption

Adds a build option to select the major Qt version if necessary, that is, if the major Qt version has not yet been determined otherwise (e.g. by a corresponding find_package() call). This module is typically included by other modules requiring knowledge about the major Qt version.

If the ECM version passed to find_package was at least 5.240.0 Qt6 is picked by default. Otherwise Qt5 is picked.

QT_MAJOR_VERSION is defined to either be “5” or “6”.

Since 5.82.0.