I would like to build qt and qt application out of the source tree. Do you know how to set from the command line the .obj directory both with configure and qmake?
If I understand question correctly you should set OBJECTS_DIR variable in *.pro file for any directory you want. If you don't want to change *.pro file try
qmake "OBJECTS_DIR=some_dir" *.pro
来源：https://stackoverflow.com/questions/1741877/qt-and-qmake-build-dir