Qt does not create output files in debug/release folders in Linux

The CONFIG variable has debug_and_release and debug_and_release_target set on windows, but not on linux. So the following line will make sure that your build will be the same on linux and windows:

CONFIG *= debug_and_release debug_and_release_target

The documentation shortly mentions it. The file /usr/share/qt4/mkspecs/win32-g++/qmake.conf adds it to CONFIG.

I assume you're using qmake to do the actual building. You can edit the project files to put the output in different directories like this:

# only for unix:
unix {
    # in debug mode...
    CONFIG(debug, debug|release) {
        DESTDIR = debug
    }
    else {
        DESTDIR = release
    }
}

Obviously in order for this to work you need to be building both debug and release executables. More information on this topic can be found here

Cheers