According to Qt's documentation the PCH header doesn't need to be included.
From https://doc.qt.io/qt-5/qmake-precompiledheaders.html:
"To make your project use precompiled headers, you only need to define the PRECOMPILED_HEADER variable in your project file."
"qmake will handle the rest, to ensure the creation and use of the precompiled header file. You do not need to include the precompiled header file in HEADERS, as qmake will do this if the configuration supports precompiled headers."
This new class wraps the existing "licenses.h"-header,
but makes it easier to use.
The existing "licenses.h"-header uses static string
literals, which means that if two source files include
the file, both object files will include the string data.
This License file is introduced to avoid that problem,
but also to provide a more Qt-like API, with QStrings
instead of C-style char *s.
