Im not sure if this is what you are asking for. But if you want qmake to only create absolute path you should put following line into your .pro file
Qt Code: 
  1. QMAKE_PROJECT_DEPTH = 0 # undocumented qmake flag to force absolute paths in make files
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It basically tells qmake that the accepted depth for a relative path is zero. So there will never be any relative paths.

You can find information about this and other undocumented features on QTs wiki page.
https://wiki.qt.io/Undocumented_QMake