Just changing the root widget of my application from QWidget to QQuickWidget fixed the problem. Well, that was way easier than I expected! Thanks for the help.

@Stefan-Monov76
The automatic deletion of QObject childs by the parents is used in whole Qt frame work and
is fully documented and will not change in any version.
http://doc.qt.io/qt-5/objecttrees.html

Hi,

I'd recommend checking out the bug report system to see if it's something known. If not then please consider opening a new report providing your sample application as well as system specification.

I got a working solution (in comments) here.

Then you should use the Qt resource system to embed the shader in your application. You current shader files are accessible on your host. When you start your application on your device, they won't be there.

Glad you found out and thanks for sharing !

Since you have it working now please mark the thread as solved using the"Topic Tool" button so that other forum users may know a solution has been found :)

Another interesting development: I tried running on another machine with the Qt toolchain installed, and the program worked. So it appears it is still reading something from the filesystem that is not on a regular Windows machine, but I don't know what that might be. I did package all the qmldir files needed for Qt Quick to work.