pub type clGetSemaphoreHandleForTypeKHR_fn = Option<unsafe extern "C" fn(sema_object: cl_semaphore_khr, device: cl_device_id, handle_type: cl_external_semaphore_handle_type_khr, handle_size: size_t, handle_ptr: *mut c_void, handle_size_ret: *mut size_t) -> cl_int>;