pub type clGetKernelSubGroupInfoKHR_fn = Option<unsafe extern "C" fn(in_kernel: cl_kernel, in_device: cl_device_id, param_name: cl_kernel_sub_group_info, input_value_size: size_t, input_value: *const c_void, param_value_size: size_t, param_value: *mut c_void, param_value_size_ret: *mut size_t) -> cl_int>;