Linking against ${DART_LIBRARIES} not working in Ubuntu 14.04

[a-price]

Linking executable "test" against DART using the find_package supplied variable doesn't seem to be working for me:
target_link_libraries(test ${DART_LIBRARIES})
However, linking to "dart" works fine:
target_link_libraries(test dart)

Running the build system with make VERBOSE=1 gives the following output using ${DART_LIBRARIES}:

c++ -std=c++0x CMakeFiles/test.dir/test.cpp.o -o test -rdynamic /usr/local/lib/libdart.so -Wl,-rpath,/usr/local/lib

but returns the following when using dart:

c++ -std=c++0x CMakeFiles/test.dir/test.cpp.o -o test -rdynamic /usr/local/lib/libdart.so.5.1.1 /usr/local/lib/libdart-core.so.5.1.1 /opt/ros/indigo/lib/libccd.so /opt/ros/indigo/lib/libfcl.so -lassimp -lboost_regex -lboost_system -lGLU -lGL -lSM -lICE -lX11 -lXext -lglut -lXmu -lXi -lurdfdom_sensor -lurdfdom_model_state -lurdfdom_model -lurdfdom_world -lconsole_bridge -ltinyxml -ltinyxml2 -Wl,-rpath,/usr/local/lib:/opt/ros/indigo/lib

So it would appear that the dependencies of libdart.so are not getting pulled in correctly in the first method. I've attached a minimum (non)working example:
CMakeLists.txt
test.txt
(Apologies for the .txt extension for the .cpp file, GitHub doesn't support uploading .cpp's)

[mkoval]

👍 👍 👍 I've also ran into a lot of difficult-to-reproduce problems with DART_LIBRARIES missing transitive dependencies (e.g. assimp, tinyxml, etc).

It's important to remember that CMake has two different ways of find_packageing:

1. module mode: Searches for a FindXXX.cmake file in CMAKE_MODULE_PATH that is provided by a third-party for a package that does not use CMake as its build system. The .cmake file should generate full paths using helper functions like find_library and find_path.
2. config mode: Searches for a XXXConfig.cmake file in CMAKE_PREFIX_PATH that is *generated and installed by the package's own CMakeLists.txt file. This .cmake file should include the auto-generated XXXTargets.cmake and, optionally, a XXXVersion.cmake files. These auto-generated files create imported CMake targets with the target properties required for linking (e.g. absolute path) already set.

DART currently mixes the two. It generates a DARTTargets.cmake file, but then resolves each library to an absolute path using find_library. This cause CMake to ignore all of the meta-data that DARTTargets.cmake file sets on the imported targets!

TL;DR: Fixing this should be as simple removing the find_library calls in DARTConfig.cmake.in.

Edit: We also should not add "@CMAKE_INSTALL_PREFIX@/lib" to DART_LIBRARY_DIRS. It is not necessary, because CMake knows about the full paths.

[jslee02]

I believe this is addressed by #630. Thanks @a-price !