Here is a temporary workaround that will squelch this error on Intel CL 2.0 CPU compilers while supporting a CL1.2 GPU target like Apollo Lake:
#if (__OPENCL_VERSION__ == CL_VERSION_1_2) && defined ( cl_intel_subgroups ) || defined ( cl_khr_subgroups )
Sorry for the delayed reply. Glad you've found a workaround.
I've replicated your report with the 4729 driver, and a bug report is filed. As I've investigated, I've found some strange (but unrelated) behavior with this driver and Intel(R) SDK for OpenCL(tm) Applications 2016 R3 too. The 4729 driver build is from the new 15.46 branch.
Until the next SDK release you may have better results on the 15.45 driver branch. I tested with the latest 15.45 release, 18.104.22.16878, and was not able to replicate the behavior you've described.