Unsolved Build QWT as subproject

[kenfred]

I am attempting to build QWT as a static lib and link against it in my application. I do not want to install QWT, but rather build it at the same time as my app as a subproject.

I have set the appropriate options in qwtconfig.pri and can successfully build the qwt lib on its own. The qwt.pro file uses the subdirs template, meaning each of its subfolders has its own .pro file and is built individually. Then there are custom qwtfunctions which gather the resulting .obj files and package them into a single static lib.

Now I'd like to build qwt as a subproject to my app. My first (failed) approach was to include(qwt.pro) in my app.pro file. However, qwt is not built in this case. After further reading, my second approach was to create a root subdirs project file, making my app and qwt subdirs. In this case, qwt is built but it does not package up the .obj files into the static lib!

Please, does anyone know enough about QWT and/or the Qt build system to help me understand why the lib isn't created? Using messages I'm able to tell that the custom qwtfunctions are being called, but I have no means to debug further. Much appreciated.