Implement Empty method for host device vector. (#5781)

* Fix accessing nullptr.
2020-06-13 19:02:26 +08:00
parent 306e38ff31
commit 1fa84b61c1
3 changed files with 11 additions and 1 deletions
--- a/include/xgboost/host_device_vector.h
+++ b/include/xgboost/host_device_vector.h
@@ -95,6 +95,7 @@ class HostDeviceVector {
  HostDeviceVector<T>& operator=(const HostDeviceVector<T>&) = delete;
  HostDeviceVector<T>& operator=(HostDeviceVector<T>&&);

+  bool Empty() const { return Size() == 0; }
  size_t Size() const;
  int DeviceIdx() const;
  common::Span<T> DeviceSpan();