message: fix regression in DiffArray::zero_
diff: @@ -652,7 +652,7 @@ struct CUDAArray : ArrayBase<value_t<Value>, CUDAArray<Value>> {
  return CUDAArray(Value(0));
  } else {
  void *ptr = cuda_malloc(size * sizeof(Value));
  - cuda_fill((uint8_t *) ptr, 0, size);
  + cuda_fill((uint8_t *) ptr, 0, size * sizeof(Value));
  uint32_t index = cuda_var_register(Type, size, ptr, true);
  return CUDAArray::from_index_(index);
  }
  