Internal change

PiperOrigin-RevId: 437984955
Change-Id: Ic98b54194b7df185756a374f691e3d1827c275e1
diff --git a/unsupported/Eigen/CXX11/src/Tensor/TensorTrace.h b/unsupported/Eigen/CXX11/src/Tensor/TensorTrace.h
index 5140906..d0048aa 100644
--- a/unsupported/Eigen/CXX11/src/Tensor/TensorTrace.h
+++ b/unsupported/Eigen/CXX11/src/Tensor/TensorTrace.h
@@ -137,6 +137,7 @@
     }
 
     eigen_assert(num_distinct_reduce_dims == NumReducedDims);
+    EIGEN_ONLY_USED_FOR_DEBUG(num_distinct_reduce_dims);
 
     // Compute the dimensions of the result.
     const typename TensorEvaluator<ArgType, Device>::Dimensions& input_dims = m_impl.dimensions();