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Using QT without install

  • Hi,

    I'm experimenting with a Qt project setup that should be self contained and build/run on multiple platforms, that should support cross compilation, and should be able to consume multiple Qt versions. The way I planned to do this is to create a self contained project directory tree with a set of env scripts that configure the environment prior to use according to the local platform. The project directory tree also contains the Qt sources and the shadow build results in extra qt-build directories.

    Now I'm surprised to find that on windows this approach works fine, but on linux the built Qt version has to be installed (i.e. make install has to be run after make). Why is that so? Can I configure the environment or Qt build is such a way that I can build my software against a self compiled Qt SDK without installing in on Linux?

    Sorry if I may confuse you with my use of terminology. I am an experienced software engineer but new to Qt and I fear I may use some terms incorrectly in the Qt context.

    Best Regards,


  • It is not correct that Qt needs to be installed on linux, but linux uses another technique to idetify libraries than windows.

    On windows, libraries are searched inside the PATH.

    On Linux, executables are searched by PATH. Libaries are searched by LD_LIBRARY_PATH.

  • Hi, thanks. This may be the difference that caused some of my problems. However when I execute qmake without the LD_LIBRARY_PATH set I get:

    QMAKESPEC has not been set, so configuration cannot be deduced.
    Error processing project file: ../../src/0.0.1/

    If I then install the Qt SDK I want to build against qmake runs through without problems. This error message is not just a little misleading IMO.

    Best Regards,


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