The Xilinx-specific test is disabled for now, because it is not out-of-source friendly and requires changes to the source code, but because I do not have such an SDK, I cannot test it. For an OpenCL application to always find the kernel code, one could obtain the neccessary info from the build system, such as can be seen in a repo of mine that uses CMakes configure_file option to create a header with the path to the kernel.
One has many other options, such as always copying the kernel code over to the binary dir with the
file(COPY ... DESTINATION ...) command. Byproducts created by external tools from the SDK can use custom_target command and specify BYPRODUCTS of invoking the target which the original target can depend on simply by adding them to the input files.