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Can't cross compile modules for raspberry pi

  • I'm a neofite in Qt, and I am trying to set up a development enviroment to cross compile for a raspberry pi 2 that will form an embedded system for a motorcycle.

    I am using Qt 5.5.1 (tried 5.6 aswell, but i prefer to stay on the stable release if possible), and buildroot with minimal packages (just Qt and CANBUS support) as operating system for the raspberry pi.

    For now i just want to run some tests, and get the example "Qt Quick Extras - Dashboard" (somewhat close to what i want as the interface of my raspberry, fed with real data) from Qt 5.5.1 examples compiled for my platform. I have been following this guide: , got qmake working, and managed to compile a "hello world" program, but it seems that i am missing some libraries (Qt quick most notably) to compile the whole dashboard project:

    I tried to compile Qt Quick from source like the wiki says, cloning the 5.5.1 version of the corresponding repo and calling qmake

    ~/raspi/qt5/bin/qmake -r

    ...but I get an error

    Project ERROR: Unknown module(s) in QT: qml quick quick-private qml-private

    I guess i must compile some other modules first, but I'm not sure what I am looking for. Searched for solutions ( but none of them seemed related to my problem.

    Any help will be really appreciated.

  • Lifetime Qt Champion

    Hi and welcome to devnet,

    IIRC, you need to build the QtDeclarative and QtQuickControls module

  • Many thanks for your help. It worked after compiling QtDeclarative. Now It seems I am missing QtGraphicalEffects, will look into it tomorrow. I should also find a workarround to show my application fullscreen with no window system at all (or is that behaviour already implemented in the Window class?)

    Just curious, How can I know the dependencys? Is it possible to know only from the error output? I did not see any reference pointing QtDeclarative until you wisely stated it.

    edit: Finally could not wait and got it working. Thank you for your help again :)

  • This post is deleted!

  • @Igbf Look at Qt documentation, every module have dependencies described.

  • I might be looking in the wrong places, but i can't find the dependencies listed in the documentation, for example i see no trace of QtDeclarative arround:

    No luck in the compiling instructions either. You meant the wiki maybe?

  • Lifetime Qt Champion

    I don't remember if there's a defined place in the documentation for that but since you have the source, take a look at the sync.profile file.

  • @SGaist Thanks, that is what i was looking for.

  • @SGaist
    I am newbie to QT. I am facing same error for qml-private. Can you tell me how I can build QtDeclarative?

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