Arguments to __kernel functions in a program cannot be declared with the built-in
scalar types bool, half, size_t, ptrdiff_t, intptr_t, and uintptr_t. The
size in bytes of these types except half are implementation-defined and in addition can
also be different for the OpenCL device and the host processor making it difficult to
allocate buffer objects to be passed as arguments to a kernel declared as pointer to these
types. half is not supported as half can be used as a storage format only and is not a
data type on which floating-point arithmetic can be performed.