diff --git a/test/test_forward_list.cpp b/test/test_forward_list.cpp
index 03ac1e55..50169e7d 100644
--- a/test/test_forward_list.cpp
+++ b/test/test_forward_list.cpp
@@ -168,8 +168,9 @@ namespace
       CompareDataNDC compare_data(INITIAL_SIZE, VALUE);
       compare_data.resize(NEW_SIZE);
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -186,8 +187,9 @@ namespace
       CompareDataNDC compare_data(INITIAL_SIZE, VALUE);
       compare_data.resize(NEW_SIZE, VALUE);
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -213,8 +215,9 @@ namespace
       CompareDataNDC compare_data(INITIAL_SIZE, VALUE);
       compare_data.resize(NEW_SIZE);
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -231,8 +234,9 @@ namespace
       CompareDataNDC compare_data(INITIAL_SIZE, VALUE);
       compare_data.resize(NEW_SIZE, VALUE);
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -255,8 +259,9 @@ namespace
       data.assign(compare_data.begin(), compare_data.end());
       data.assign(compare_data.begin(), compare_data.end());
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -273,8 +278,9 @@ namespace
       data.assign(INITIAL_SIZE, VALUE);
       data.assign(INITIAL_SIZE, VALUE);
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -309,8 +315,9 @@ namespace
       data.insert_after(i_data, INSERT_VALUE);
       compare_data.insert_after(i_compare_data, INSERT_VALUE);
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
 
       offset = 0;
@@ -324,8 +331,9 @@ namespace
       data.insert_after(i_data, INSERT_VALUE);
       compare_data.insert_after(i_compare_data, INSERT_VALUE);
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -350,8 +358,9 @@ namespace
       data.insert_after(i_data, 2, INSERT_VALUE);
       compare_data.insert_after(i_compare_data, 2, INSERT_VALUE);
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
 
       offset = 0;
@@ -365,8 +374,9 @@ namespace
       data.insert_after(i_data, 2, INSERT_VALUE);
       compare_data.insert_after(i_compare_data, 2, INSERT_VALUE);
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -382,8 +392,9 @@ namespace
       compare_data.insert_after(compare_data.before_begin(), test2.begin(), test2.end());
       data.insert_after(data.before_begin(), test2.begin(), test2.end());
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
 
       compare_data.assign(test1.begin(), test1.end());
@@ -398,8 +409,9 @@ namespace
       compare_data.insert_after(icd, test2.begin(), test2.end());
       data.insert_after(id, test2.begin(), test2.end());
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -426,8 +438,9 @@ namespace
       CHECK_EQUAL(6U, data.size());
       CHECK_EQUAL(6, std::distance(data.begin(), data.end()));
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -552,16 +565,18 @@ namespace
       i_compare_data = compare_data.erase_after(i_compare_data);
       i_data         = data.erase_after(i_data);
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
       CHECK(*i_compare_data == *i_data);
 
       i_compare_data = compare_data.erase_after(compare_data.begin());
       i_data         = data.erase_after(data.begin());
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
 
       are_equal = *i_data == *i_compare_data;
@@ -576,6 +591,8 @@ namespace
       //std::advance(i_data, data.size() - 1);
       i_data = data.erase_after(i_data);
 
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
+
       are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
 
       CHECK(are_equal);
@@ -607,6 +624,8 @@ namespace
 
       CHECK_EQUAL(*i_compare_result, *i_result);
 
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
+
       are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
@@ -629,6 +648,8 @@ namespace
 
       CHECK(i_result == data.end());
 
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
+
       are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
@@ -664,7 +685,6 @@ namespace
       CHECK_EQUAL(data.size(), other_data.size());
 
       are_equal = std::equal(data.begin(), data.end(), other_data.begin());
-
       CHECK(are_equal);
     }
 
@@ -680,7 +700,6 @@ namespace
       idata2 = idata1;
 
       bool isEqual = std::equal(data1.begin(), data1.end(), data2.begin());
-
       CHECK(isEqual);
     }
 
@@ -696,7 +715,6 @@ namespace
       CHECK_EQUAL(data.size(), other_data.size());
 
       are_equal = std::equal(data.begin(), data.end(), other_data.begin());
-
       CHECK(are_equal);
     }
 
@@ -709,8 +727,9 @@ namespace
       compare_data.unique();
       data.unique();
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -723,8 +742,9 @@ namespace
       compare_data.unique();
       data.unique();
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -737,8 +757,9 @@ namespace
       compare_data.remove(ItemNDC("7"));
       data.remove(ItemNDC("7"));
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -751,8 +772,9 @@ namespace
       compare_data.remove_if(std::bind2nd(std::equal_to<ItemNDC>(), ItemNDC("7")));
       data.remove_if(std::bind2nd(std::equal_to<ItemNDC>(), ItemNDC("7")));
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -768,8 +790,9 @@ namespace
       CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
       CHECK_EQUAL(data.size(), std::distance(data.begin(), data.end()));
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -783,7 +806,6 @@ namespace
       data.reverse();
 
       are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
-
       CHECK(are_equal);
     }
 
@@ -796,8 +818,9 @@ namespace
       compare_data.sort();
       data.sort();
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -810,8 +833,9 @@ namespace
       compare_data.sort();
       data.sort();
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -840,8 +864,9 @@ namespace
       compare_data.splice_after(i_compare_to_before, compare_data, i_compare_from_before);
       data.move_after(i_from_before, i_to_before);
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
 
       // Move to the end.
@@ -860,8 +885,9 @@ namespace
       compare_data.splice_after(i_compare_to_before, compare_data, i_compare_from_before);
       data.move_after(i_from_before, i_to_before);
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
 
       // Move to nearby.
@@ -880,8 +906,9 @@ namespace
       compare_data.splice_after(i_compare_to_before, compare_data, i_compare_from_before);
       data.move_after(i_from_before, i_to_before);
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
 
       // Move to same.
@@ -900,8 +927,9 @@ namespace
       compare_data.splice_after(i_compare_to_before, compare_data, i_compare_from_before);
       data.move_after(i_from_before, i_to_before);
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -938,8 +966,9 @@ namespace
       compare_data.splice_after(i_compare_to_before, compare_data, i_compare_first_before, i_compare_last);
       data.move_after(i_first_before, i_last, i_to_before);
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(std::distance(compare_data.begin(), compare_data.end()), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
 
       // Move to the end.
diff --git a/test/test_list.cpp b/test/test_list.cpp
index e8bb91b5..cc80886a 100644
--- a/test/test_list.cpp
+++ b/test/test_list.cpp
@@ -235,6 +235,8 @@ namespace
       CompareData compare_data(INITIAL_SIZE, VALUE);
       compare_data.resize(NEW_SIZE, VALUE);
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
 
       CHECK(are_equal);
@@ -385,8 +387,9 @@ namespace
       compare_data.insert(compare_data.begin(), test2.begin(), test2.end());
       data.insert(data.begin(), test2.begin(), test2.end());
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(compare_data.size(), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
 
       compare_data.assign(test1.begin(), test1.end());
@@ -395,8 +398,9 @@ namespace
       compare_data.insert(compare_data.end(), test2.begin(), test2.end());
       data.insert(data.end(), test2.begin(), test2.end());
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(compare_data.size(), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
 
       compare_data.assign(test1.begin(), test1.end());
@@ -411,8 +415,9 @@ namespace
       compare_data.insert(icd, test2.begin(), test2.end());
       data.insert(id, test2.begin(), test2.end());
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(compare_data.size(), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -436,8 +441,9 @@ namespace
       CHECK_NO_THROW(data.push_front(ItemNDC("5")));
       CHECK_NO_THROW(data.push_front(ItemNDC("6")));
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(compare_data.size(), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -536,8 +542,9 @@ namespace
       CHECK_NO_THROW(data.push_back(ItemNDC("5")));
       CHECK_NO_THROW(data.push_back(ItemNDC("6")));
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(compare_data.size(), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -572,8 +579,9 @@ namespace
       data.pop_back();
       data.pop_back();
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(compare_data.size(), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -608,6 +616,8 @@ namespace
       i_compare_data = compare_data.erase(i_compare_data);
       i_data         = data.erase(i_data);
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
 
       CHECK(are_equal);
@@ -616,6 +626,8 @@ namespace
       i_compare_data = compare_data.erase(compare_data.begin());
       i_data         = data.erase(data.begin());
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
 
       CHECK(are_equal);
@@ -632,6 +644,8 @@ namespace
       std::advance(i_data, data.size() - 1);
       i_data = data.erase(i_data);
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
 
       CHECK(are_equal);
@@ -661,8 +675,9 @@ namespace
 
       data.erase(i_data_1, i_data_2);
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(compare_data.size(), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -764,7 +779,6 @@ namespace
       CHECK_EQUAL(data.size(), other_data.size());
 
       are_equal = std::equal(data.begin(), data.end(), other_data.begin());
-
       CHECK(are_equal);
     }
 
@@ -777,8 +791,9 @@ namespace
       compare_data.unique();
       data.unique();
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(compare_data.size(), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -791,8 +806,9 @@ namespace
       compare_data.unique();
       data.unique();
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(compare_data.size(), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -805,8 +821,9 @@ namespace
       compare_data.remove(ItemNDC("7"));
       data.remove(ItemNDC("7"));
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(compare_data.size(), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -819,8 +836,9 @@ namespace
       compare_data.remove_if(std::bind2nd(std::equal_to<ItemNDC>(), ItemNDC("7")));
       data.remove_if(std::bind2nd(std::equal_to<ItemNDC>(), ItemNDC("7")));
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(compare_data.size(), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -850,8 +868,9 @@ namespace
       compare_data.sort();
       data.sort();
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(compare_data.size(), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -864,8 +883,9 @@ namespace
       compare_data.sort();
       data.sort();
 
-      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
+      CHECK_EQUAL(compare_data.size(), data.size());
 
+      are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
 
@@ -892,6 +912,8 @@ namespace
       to = data.begin();
       data.splice(to, data, from);
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
 
@@ -906,6 +928,8 @@ namespace
       to = data.end();
       data.splice(to, data, from);
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
 
@@ -922,6 +946,8 @@ namespace
       std::advance(to, 6);
       data.splice(to, data, from);
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
 
@@ -938,6 +964,8 @@ namespace
       std::advance(to, 4);
       data.splice(to, data, from);
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
     }
@@ -968,9 +996,13 @@ namespace
       to = data.begin();
       data.splice(to, data2, from);
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
 
+      CHECK_EQUAL(compare_data2.size(), data2.size());
+
       are_equal = std::equal(data2.begin(), data2.end(), compare_data2.begin());
       CHECK(are_equal);
 
@@ -991,9 +1023,13 @@ namespace
       to = data.end();
       data.splice(to, data2, from);
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
 
+      CHECK_EQUAL(compare_data2.size(), data2.size());
+
       are_equal = std::equal(data2.begin(), data2.end(), compare_data2.begin());
       CHECK(are_equal);
 
@@ -1016,9 +1052,13 @@ namespace
       std::advance(to, 6);
       data.splice(to, data2, from);
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
 
+      CHECK_EQUAL(compare_data2.size(), data2.size());
+
       are_equal = std::equal(data2.begin(), data2.end(), compare_data2.begin());
       CHECK(are_equal);
 
@@ -1041,9 +1081,13 @@ namespace
       std::advance(to, 4);
       data.splice(to, data2, from);
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
 
+      CHECK_EQUAL(compare_data2.size(), data2.size());
+
       are_equal = std::equal(data2.begin(), data2.end(), compare_data2.begin());
       CHECK(are_equal);
     }
@@ -1077,6 +1121,8 @@ namespace
       to = data.begin();
       data.splice(to, data, begin, end);
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
 
@@ -1095,6 +1141,8 @@ namespace
       to = data.end();
       data.splice(to, data, begin, end);
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
 
@@ -1115,6 +1163,8 @@ namespace
       std::advance(to, 7);
       data.splice(to, data, begin, end);
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
 
@@ -1128,6 +1178,9 @@ namespace
 
       DataNDC data2(data);
       data.splice(to, data, begin, end);
+
+      CHECK_EQUAL(data.size(), data2.size());
+
       are_equal = std::equal(data.begin(), data.end(), data2.begin());
       CHECK(are_equal);
 
@@ -1173,9 +1226,13 @@ namespace
       to = data.begin();
       data.splice(to, data2, begin, end);
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
 
+      CHECK_EQUAL(compare_data2.size(), data2.size());
+
       are_equal = std::equal(data2.begin(), data2.end(), compare_data2.begin());
       CHECK(are_equal);
 
@@ -1200,9 +1257,13 @@ namespace
       to = data.end();
       data.splice(to, data2, begin, end);
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
 
+      CHECK_EQUAL(compare_data2.size(), data2.size());
+
       are_equal = std::equal(data2.begin(), data2.end(), compare_data2.begin());
       CHECK(are_equal);
 
@@ -1229,9 +1290,13 @@ namespace
       std::advance(to, 7);
       data.splice(to, data2, begin, end);
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
 
+      CHECK_EQUAL(compare_data2.size(), data2.size());
+
       are_equal = std::equal(data2.begin(), data2.end(), compare_data2.begin());
       CHECK(are_equal);
     }
@@ -1255,9 +1320,13 @@ namespace
       to = data.begin();
       data.splice(to, data2);
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
 
+      CHECK_EQUAL(compare_data2.size(), data2.size());
+
       are_equal = std::equal(data2.begin(), data2.end(), compare_data2.begin());
       CHECK(are_equal);
 
@@ -1274,9 +1343,13 @@ namespace
       to = data.end();
       data.splice(to, data2);
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
 
+      CHECK_EQUAL(compare_data2.size(), data2.size());
+
       are_equal = std::equal(data2.begin(), data2.end(), compare_data2.begin());
       CHECK(are_equal);
 
@@ -1295,9 +1368,13 @@ namespace
       std::advance(to, 7);
       data.splice(to, data2);
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       are_equal = std::equal(data.begin(), data.end(), compare_data.begin());
       CHECK(are_equal);
 
+      CHECK_EQUAL(compare_data2.size(), data2.size());
+
       are_equal = std::equal(data2.begin(), data2.end(), compare_data2.begin());
       CHECK(are_equal);
     }
diff --git a/test/test_vector.cpp b/test/test_vector.cpp
index 51f1b62c..2785bb6b 100644
--- a/test/test_vector.cpp
+++ b/test/test_vector.cpp
@@ -244,6 +244,8 @@ namespace
       std::array<int, NEW_SIZE> compare_data;
       compare_data.fill(INITIAL_VALUE);
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       bool is_equal = std::equal(data.begin(), data.end(), compare_data.begin());
 
       CHECK(is_equal);
@@ -432,6 +434,8 @@ namespace
 
       data.assign(compare_data.begin(), compare_data.end());
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       bool is_equal = std::equal(data.begin(),
                                 data.end(),
                                 compare_data.begin());
@@ -450,6 +454,8 @@ namespace
       Data data;
       data.assign(INITIAL_SIZE, INITIAL_VALUE);
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       bool is_equal = std::equal(data.begin(),
                                 data.end(),
                                 compare_data.begin());
@@ -487,6 +493,8 @@ namespace
         data.push_back(i);
       }
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       bool is_equal = std::equal(data.begin(),
                                 data.end(),
                                 compare_data.begin());
@@ -505,6 +513,8 @@ namespace
       data.push_back();
       data[0] = 1;
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       bool is_equal = std::equal(data.begin(),
                                 data.end(),
                                 compare_data.begin());
@@ -537,6 +547,8 @@ namespace
       data.pop_back();
       data.pop_back();
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       bool is_equal = std::equal(data.begin(),
                                 data.end(),
                                 compare_data.begin());
@@ -623,6 +635,8 @@ namespace
         data.insert(data.begin() + offset, INSERT_SIZE, INITIAL_VALUE);
         compare_data.insert(compare_data.begin() + offset, INSERT_SIZE, INITIAL_VALUE);
 
+        CHECK_EQUAL(compare_data.size(), data.size());
+
         bool is_equal = std::equal(data.begin(),
                                    data.end(),
                                    compare_data.begin());
@@ -675,6 +689,8 @@ namespace
         data.insert(data.begin() + offset, insert_data.begin(), insert_data.end());
         compare_data.insert(compare_data.begin() + offset, insert_data.begin(), insert_data.end());
 
+        CHECK_EQUAL(compare_data.size(), data.size());
+
         bool is_equal = std::equal(data.begin(),
                                    data.end(),
                                    compare_data.begin());
@@ -719,6 +735,8 @@ namespace
 
       data.erase(data.begin() + 2);
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       bool is_equal = std::equal(data.begin(),
                                 data.end(),
                                 compare_data.begin());
@@ -736,6 +754,8 @@ namespace
 
       data.erase(data.begin() + 2, data.begin() + 4);
 
+      CHECK_EQUAL(compare_data.size(), data.size());
+
       bool is_equal = std::equal(data.begin(),
                                 data.end(),
                                 compare_data.begin());