diff --git a/internal/ceres/block_sparse_matrix.cc b/internal/ceres/block_sparse_matrix.cc
index 01dbfbe..f86666c 100644
--- a/internal/ceres/block_sparse_matrix.cc
+++ b/internal/ceres/block_sparse_matrix.cc
@@ -824,9 +824,9 @@
 #endif
 };
 
-void BlockSparseMatrix::FreeValues(double* values) {
+void BlockSparseMatrix::FreeValues(double*& values) {
   if (!use_page_locked_memory_) {
-    delete values;
+    delete[] values;
     values = nullptr;
     return;
   }
diff --git a/internal/ceres/block_sparse_matrix.h b/internal/ceres/block_sparse_matrix.h
index cd13b06..45c5021 100644
--- a/internal/ceres/block_sparse_matrix.h
+++ b/internal/ceres/block_sparse_matrix.h
@@ -163,7 +163,7 @@
 
  private:
   double* AllocateValues(int size);
-  void FreeValues(double* values);
+  void FreeValues(double*& values);
 
   const bool use_page_locked_memory_;
   int num_rows_;