target_link_libraries() reports error if its only argument is not a target.
In CMake 2.8.2 and lower the target_link_libraries() command silently ignored if it was called with only one argument, and this argument wasn’t a valid target. In CMake 2.8.3 and above it reports an error in this case.
This policy was introduced in CMake version 2.8.3. CMake version 3.0.20140506-g0eb60 warns when the policy is not set and uses OLD behavior. Use the cmake_policy command to set it to OLD or NEW explicitly.
