Automatic copying of DLLs in qmake won't work

Question

I'm trying to get qmake to automatically copy the DLLs for my program to the target path, but it's not working. This is the relevant part of my .pro-file:

QT_DIR = C:/Qt/5.1.1/mingw48_32/bin
MY_TARGET_DIR = $$PWD/debug
MY_LIB_FILES += QT_DIR/QT5CORED.DLL
MY_LIB_FILES += QT_DIR/QT5SERIALPORTD.DLL
MY_LIB_FILES += QT_DIR/QT5WIDGETSD.DLL
MY_LIB_FILES += QT_DIR/LIBGCC_S_DW2-1.DLL
MY_LIB_FILES += QT_DIR/LIBWINPTHREAD-1.DLL
MY_LIB_FILES += QT_DIR/LIBSTDC++-6.DLL
MY_LIB_FILES += C:/qwt-6.1.0/lib/QWTD.DLL
extra_libs.files = MY_LIB_FILES
extra_libs.path = MY_TARGET_DIR
INSTALLS += extra_libs

QMake runs normally, but make install issues a warning

 Nothing to be done for 'install'.

The DLLs are not copied to the target directory. Also, I tried to write the code more elegantly, but it seems that some QMake variables such as $$QMAKE_LIBDIR are empty. What am I doing wrong?

This is qmake from Qt 5.1.1 .

Answer 1

You need to prepend the QT_DIR variable with double dollars to make this work:

QT_DIR = C:/Qt/5.1.1/mingw48_32/bin
MY_TARGET_DIR = $${PWD}/debug
MY_LIB_FILES += $${QT_DIR}/QT5CORED.DLL
MY_LIB_FILES += $${QT_DIR}/QT5SERIALPORTD.DLL
MY_LIB_FILES += $${QT_DIR}/QT5WIDGETSD.DLL
MY_LIB_FILES += $${QT_DIR}/LIBGCC_S_DW2-1.DLL
MY_LIB_FILES += $${QT_DIR}/LIBWINPTHREAD-1.DLL
MY_LIB_FILES += $${QT_DIR}/LIBSTDC++-6.DLL
MY_LIB_FILES += C:/qwt-6.1.0/lib/QWTD.DLL
extra_libs.files = MY_LIB_FILES
extra_libs.path = MY_TARGET_DIR
INSTALLS += extra_libs

Side Note: There is a bug in qmake which causes that files containing special characters (like the + in the name of libstdc++-6.dll ) are not copied during install on Windows. Check my comment in the bug report for a workaround.