Hello again: This is an example of cmake test file that might help in the future detecting such issues: (stolen and adapted from mrpt)
cat ../CMakeLists.txt cmake_minimum_required(VERSION 3.16) project(test) find_package(LibFTDI1) message("Include directories: " ${LIBFTDI_INCLUDE_DIRS}) message("Link directories: " ${LIBFTDI_LIBRARY_DIRS}) message("Libraries: " ${LIBFTDI_LIBRARIES}) add_library(imp_ftdi INTERFACE IMPORTED) set_target_properties(imp_ftdi PROPERTIES INTERFACE_INCLUDE_DIRECTORIES "${LIBFTDI_INCLUDE_DIRS}" INTERFACE_LINK_DIRECTORIES "${LIBFTDI_LIBRARY_DIRS}" INTERFACE_LINK_LIBRARIES "${LIBFTDI_LIBRARIES}" ) add_executable(main main.c) target_link_libraries(main PRIVATE imp_ftdi) $ cmake .. Include directories: /usr/include/libftdi1 Link directories: lib/x86_64-linux-gnu Libraries: ftdi1/usr/lib/x86_64-linux-gnu/libusb-1.0.so -- Configuring done CMake Error in CMakeLists.txt: Target "imp_ftdi" contains relative path in its INTERFACE_LINK_DIRECTORIES: "lib/x86_64-linux-gnu" CMake Error in CMakeLists.txt: Target "imp_ftdi" contains relative path in its INTERFACE_LINK_DIRECTORIES: "lib/x86_64-linux-gnu" -- Generating done CMake Generate step failed. Build files cannot be regenerated correctly. and this is the patch that fixes the issue: diff -Nru libftdi1-1.5/debian/changelog libftdi1-1.5/debian/changelog --- libftdi1-1.5/debian/changelog 2020-07-17 08:57:55.000000000 +0200 +++ libftdi1-1.5/debian/changelog 2020-07-17 09:19:25.000000000 +0200 @@ -1,3 +1,9 @@ +libftdi1 (1.5-3.1) unstable; urgency=medium + + * Add again the LIBDIR in rules file to make the cmake script happy (Closes: #-1) + + -- Gianfranco Costamagna <locutusofb...@debian.org> Fri, 17 Jul 2020 09:19:25 +0200 + libftdi1 (1.5-3ubuntu1) groovy; urgency=medium * Mark one symbol as optional, disappearing on ppc64el with -O3 diff -Nru libftdi1-1.5/debian/rules libftdi1-1.5/debian/rules --- libftdi1-1.5/debian/rules 2020-07-13 11:23:42.000000000 +0200 +++ libftdi1-1.5/debian/rules 2020-07-17 09:19:25.000000000 +0200 @@ -11,6 +11,7 @@ override_dh_auto_configure: dh_auto_configure --builddirectory=build-main -- \ -DBUILD_TESTS=ON \ + -DCMAKE_INSTALL_LIBDIR="/usr/lib/$(DEB_HOST_MULTIARCH)" \ -DDOCUMENTATION:BOOL=ON \ -DEXAMPLES:BOOL=ON \ -DFTDIPP:BOOL=ON \ @@ -19,6 +20,7 @@ for v in $(PY3VERS) ; do \ dh_auto_configure --builddirectory=build-python$$v -- \ -DBUILD_TESTS=OFF \ + -DCMAKE_INSTALL_LIBDIR="/usr/lib/$(DEB_HOST_MULTIARCH)" \ -DDOCUMENTATION:BOOL=OFF \ -DEXAMPLES:BOOL=OFF \ -DFTDIPP:BOOL=ON \