add (xfailed) test for cwise add compiles or not
add (xfailed) test for cwise add compiles or not

hughperkins/cuda-on-cl,hughperkins/coriander,hughperkins/cuda-on-cl,hughperkins/cuda-on-cl,hughperkins/coriander,hughperkins/coriander,hughperkins/coriander,hughperkins/cuda-on-cl