},
            nullptr),
        TF_DeleteTensor);
    // TODO(allenl): Here and when executing regular operations, we could hold
    // on to one TFE_Op per device and just call TFE_ResetOp to avoid parsing
    // device names repeatedly.
    std::unique_ptr<TFE_Op, decltype(&TFE_DeleteOp)> const_op(
        TFE_NewOp(context, "Const", status), TFE_DeleteOp);
    if (TF_GetCode(status) != TF_OK) return nullptr;

// TODO(b/166642410): It would be nice, for custom devices and for other users,
// to have a non-string representation of devices (TF_Device) extracted from
// tensors/ops/etc. and usable in APIs like OpSetDevice/ResetOp/etc.

#define TFE_CUSTOM_DEVICE_VERSION 4

// Struct to be filled in. Functions are required except where indicated.
typedef struct TFE_CustomDevice {
  int version = TFE_CUSTOM_DEVICE_VERSION;