After appropriate link flags are determined, they are added to the INTERFACE_LINK_OPTIONS property. Unfortunately this property was added in 3.13, and thus static builds on Windows for instance failed with missing symbols due to missing system libraries on the link command line, when the CMake version was lower. When detecting a lower version, add the flags instead to INTERFACE_LINK_LIBRARIES, which is a property that is available in older CMake versions. To do this we have to strip the SHELL: prefix, which means that the added link flags might get deduplicated, and thus it can happen that the linking phase might still fail. Nevertheless, on Windows this improves the situation when using an older CMake version. Amends 44602224bfae7bea08e5883768cfeef6629ac503 Task-number: QTBUG-38913 Change-Id: Ib710b8ea691d4a9281dcd5f5b9700b11df0a5c10 Reviewed-by: Kyle Edwards <kyle.edwards@kitware.com> Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>