FFmpeg records its library dir in INTERFACE_LINK_DIRECTORIES, its INTERFACE_LINK_LIBRARIES are library names without directories. Currently FFmpeg's linker flags in pri and prl files is broken, such as "-llibavcodec.a" in QMAKE_PRL_LIBS (should be "-lavcodec"), and "libavformat.a ws2_32" in QMAKE_LIBS_FFMPEG (should be "-lavformat -lws2_32"). Fix this by enabling qt_get_library_name_without_prefix_and_suffix() and qt_get_library_with_link_flag() to handle args like "libavformat.a" and "ws2_32", to produce correct -l flags. Also avoid adding duplicate "-L" flags in pri and prl files, since all FFmpeg libraries are installed in the same location. (Amends 2c49f85380d7ad79d9473e0f42e7afaa36d31af9 and 2915921ad2a79a4ce1651dc7297f6571788d1413) On a Mingw static build with static FFmpeg, and FFmpeg libraries isn't installed in compiler's implicit link directories. Before this change: // mkspecs/modules/qt_lib_multimedia_private.pri QMAKE_LIBS_FFMPEG = libswscale.a libswscale.a libswresample.a libswresample.a libavutil.a bcrypt libavutil.a libavformat.a ws2_32 secur32 libavformat.a libavcodec.a ole32 strmiids ole32 mfuuid libavcodec.a // plugins/multimedia/ffmpegmediaplugin.prl QMAKE_PRL_LIBS = ... -llibavformat.a -lmfuuid -lstrmiids -lole32 -llibavcodec.a -llibswresample.a -llibswscale.a -lbcrypt -llibavutil.a After this change: // mkspecs/modules/qt_lib_multimedia_private.pri QMAKE_LIBS_FFMPEG = -lswscale -lswscale -lswresample -lswresample -lavutil -lbcrypt -lavutil -lavformat -lws2_32 -lsecur32 -lavformat -lavcodec -lole32 -lstrmiids -lole32 -lmfuuid -lavcodec // plugins/multimedia/ffmpegmediaplugin.prl QMAKE_PRL_LIBS = ... -lavformat -lmfuuid -lstrmiids -lole32 -lavcodec -lswresample -lswscale -lbcrypt -lavutil Fixes: QTBUG-126773 Pick-to: 6.8 6.7 Change-Id: I71a06c960a4f9b6010fc2847cc08833d58b74e1c Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>