diff --git a/internal/ceres/suitesparse.cc b/internal/ceres/suitesparse.cc
index c02d305..96c1d6c 100644
--- a/internal/ceres/suitesparse.cc
+++ b/internal/ceres/suitesparse.cc
@@ -224,7 +224,7 @@
       vector<int>::const_iterator it = lower_bound(row_block_starts.begin(),
                                                    row_block_starts.end(),
                                                    scalar_rows[idx]);
-      DCHECK(it != row_block_starts.end());
+
       // Only consider the first row of each row block.
       if (*it != scalar_rows[idx]) {
         continue;
diff --git a/internal/ceres/suitesparse_test.cc b/internal/ceres/suitesparse_test.cc
index 0dc418f..7e688d9 100644
--- a/internal/ceres/suitesparse_test.cc
+++ b/internal/ceres/suitesparse_test.cc
@@ -115,7 +115,7 @@
   //     [1 2 3 2]
   // [1]  x   x
   // [2]    x   x
-  // [1]  x x
+  // [2]  x x
   // num_nonzeros = 1 + 3 + 4 + 4 + 1 + 2 = 15
 
   vector<int> col_blocks;
@@ -127,12 +127,12 @@
   vector<int> row_blocks;
   row_blocks.push_back(1);
   row_blocks.push_back(2);
-  row_blocks.push_back(1);
+  row_blocks.push_back(2);
 
-  TripletSparseMatrix tsm(4, 8, 15);
+  TripletSparseMatrix tsm(5, 8, 18);
   int* rows = tsm.mutable_rows();
   int* cols = tsm.mutable_cols();
-  fill(tsm.mutable_values(), tsm.mutable_values() + 15, 1.0);
+  fill(tsm.mutable_values(), tsm.mutable_values() + 18, 1.0);
   int offset = 0;
 
 #define CERES_TEST_FILL_BLOCK(row_block_id, col_block_id) \