diff --git a/tests/test-marray.c b/tests/test-marray.c
index d3a5f25c..3a72a8b4 100644
--- a/tests/test-marray.c
+++ b/tests/test-marray.c
@@ -245,6 +245,67 @@ static void test_mpz(void)
   assert (array_mpz_equal_p (array1, array2));
   fclose(f);
 
+  f = m_core_fopen ("a-marray.dat", "wt");
+  if (!f) abort();
+  fprintf(f, "array");
+  fclose (f);
+  f = m_core_fopen ("a-marray.dat", "rt");
+  if (!f) abort();
+  b = array_mpz_in_str (array2, f);
+  assert (b == false);
+  fclose(f);
+
+  f = m_core_fopen ("a-marray.dat", "wt");
+  if (!f) abort();
+  fprintf(f, "[");
+  fclose (f);
+  f = m_core_fopen ("a-marray.dat", "rt");
+  if (!f) abort();
+  b = array_mpz_in_str (array2, f);
+  assert (b == false);
+  fclose(f);
+
+  f = m_core_fopen ("a-marray.dat", "wt");
+  if (!f) abort();
+  fprintf(f, "[17");
+  fclose (f);
+  f = m_core_fopen ("a-marray.dat", "rt");
+  if (!f) abort();
+  b = array_mpz_in_str (array2, f);
+  assert (b == false);
+  fclose(f);
+
+  f = m_core_fopen ("a-marray.dat", "wt");
+  if (!f) abort();
+  fprintf(f, "[17,");
+  fclose (f);
+  f = m_core_fopen ("a-marray.dat", "rt");
+  if (!f) abort();
+  b = array_mpz_in_str (array2, f);
+  assert (b == false);
+  fclose(f);
+
+  f = m_core_fopen ("a-marray.dat", "wt");
+  if (!f) abort();
+  fprintf(f, "[17,18");
+  fclose (f);
+  f = m_core_fopen ("a-marray.dat", "rt");
+  if (!f) abort();
+  b = array_mpz_in_str (array2, f);
+  assert (b == false);
+  fclose(f);
+
+  f = m_core_fopen ("a-marray.dat", "wt");
+  if (!f) abort();
+  fprintf(f, "[]");
+  fclose (f);
+  f = m_core_fopen ("a-marray.dat", "rt");
+  if (!f) abort();
+  b = array_mpz_in_str (array2, f);
+  assert (b == true);
+  fclose(f);
+  assert(array_mpz_empty_p(array2));
+  
   array_mpz_reset(array1);
 
   M_LET(str, STRING_OPLIST) {
@@ -278,6 +339,12 @@ static void test_mpz(void)
     assert(strcmp(sp, "") == 0);
     assert(array_mpz_equal_p(array1, array2));
 
+    array_mpz_push_back(array1, z);
+    assert(!array_mpz_equal_p(array1, array2));
+    testobj_set_ui (z, 43);
+    array_mpz_push_back(array2, z);
+    assert(!array_mpz_equal_p(array1, array2));
+
     b = array_mpz_parse_str(array2, "[", &sp);
     assert(!b);
     b = array_mpz_parse_str(array2, "[17,", &sp);
@@ -408,6 +475,10 @@ static void test_d(void)
   
   array_uint_init_set (a2, a1);
   assert (array_uint_equal_p (a2, a1));
+  array_uint_push_back(a2, 890);
+  assert (!array_uint_equal_p (a2, a1));
+  array_uint_push_back(a1, 891);
+  assert (!array_uint_equal_p (a2, a1));
 
   size_t h = array_uint_hash(a2);
   assert (h != 0);
diff --git a/tests/test-mbitset.c b/tests/test-mbitset.c
index 8973a594..cf3ad3fa 100644
--- a/tests/test-mbitset.c
+++ b/tests/test-mbitset.c
@@ -380,6 +380,8 @@ static void test_clz(void)
   }
 
   M_LET(s1, bitset_t) {
+    bitset_reset(s1);
+    assert(bitset_ctz(s1) == 0);
     bitset_set_str(s1, "[00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000]");
     assert(bitset_ctz(s1) == 116);
     bitset_set_str(s1, "[10000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000]");
diff --git a/tests/test-milist.c b/tests/test-milist.c
index 7e22bbf6..f8e6e487 100644
--- a/tests/test-milist.c
+++ b/tests/test-milist.c
@@ -120,12 +120,7 @@ static void test(void)
   assert (ilist_tname_size(list) == 0);
   assert (ilist_tname_empty_p(list));
   
-  for M_EACH(item, list, ILIST_OPLIST(ilist_tname)) {
-      (void)item;
-      if (M_UNLIKELY_NOMEM(1)) {
-        assert(false);
-      }
-    }
+  for M_EACH(item, list, ILIST_OPLIST(ilist_tname)) ( (void)item, assert(false) );
 
   ilist_tname_push_back (list, &x3);
   assert (ilist_tname_size (list) == 1);
diff --git a/tests/test-mlist.c b/tests/test-mlist.c
index d5eafbd1..ff21caf7 100644
--- a/tests/test-mlist.c
+++ b/tests/test-mlist.c
@@ -314,6 +314,73 @@ static void test_mpz(void)
   assert (list_mpz_equal_p (v, list2));
   list_mpz_clear(list2);
 
+  f = m_core_fopen ("a-mlist.dat", "wt");
+  if (!f) abort();
+  fprintf(f, "[");
+  fclose (f);
+  list_mpz_init(list2);
+  f = m_core_fopen ("a-mlist.dat", "rt");
+  b = list_mpz_in_str (list2, f);
+  assert (b == false);
+  fclose(f);
+  list_mpz_clear(list2);
+
+  f = m_core_fopen ("a-mlist.dat", "wt");
+  if (!f) abort();
+  fprintf(f, "[17");
+  fclose (f);
+  list_mpz_init(list2);
+  f = m_core_fopen ("a-mlist.dat", "rt");
+  b = list_mpz_in_str (list2, f);
+  assert (b == false);
+  fclose(f);
+  list_mpz_clear(list2);
+
+  f = m_core_fopen ("a-mlist.dat", "wt");
+  if (!f) abort();
+  fprintf(f, "[17,");
+  fclose (f);
+  list_mpz_init(list2);
+  f = m_core_fopen ("a-mlist.dat", "rt");
+  b = list_mpz_in_str (list2, f);
+  assert (b == false);
+  fclose(f);
+  list_mpz_clear(list2);
+
+  f = m_core_fopen ("a-mlist.dat", "wt");
+  if (!f) abort();
+  fprintf(f, "[17,18");
+  fclose (f);
+  list_mpz_init(list2);
+  f = m_core_fopen ("a-mlist.dat", "rt");
+  b = list_mpz_in_str (list2, f);
+  assert (b == false);
+  fclose(f);
+  list_mpz_clear(list2);
+
+  f = m_core_fopen ("a-mlist.dat", "wt");
+  if (!f) abort();
+  fprintf(f, "]");
+  fclose (f);
+  list_mpz_init(list2);
+  f = m_core_fopen ("a-mlist.dat", "rt");
+  b = list_mpz_in_str (list2, f);
+  assert (b == false);
+  fclose(f);
+  list_mpz_clear(list2);
+
+  f = m_core_fopen ("a-mlist.dat", "wt");
+  if (!f) abort();
+  fprintf(f, "[]");
+  fclose (f);
+  list_mpz_init(list2);
+  f = m_core_fopen ("a-mlist.dat", "rt");
+  b = list_mpz_in_str (list2, f);
+  assert (b == true);
+  fclose(f);
+  assert(list_mpz_empty_p(list2));
+  list_mpz_clear(list2);
+
   list_mpz_reset(v);
   list_mpz_init(list2);
   M_LET(str, STRING_OPLIST) {
@@ -346,6 +413,20 @@ static void test_mpz(void)
     assert(b);
     assert(strcmp(sp, "") == 0);
     assert(list_mpz_equal_p(v, list2));
+    assert(list_mpz_equal_p(v, v));
+    assert(list_mpz_equal_p(list2, list2));
+
+    b = list_mpz_parse_str(list2, "[17,18", &sp);
+    assert(!b);
+
+    b = list_mpz_parse_str(list2, "[17,", &sp);
+    assert(!b);
+
+    b = list_mpz_parse_str(list2, "[17", &sp);
+    assert(!b);
+
+    b = list_mpz_parse_str(list2, "[", &sp);
+    assert(!b);
   }
   
   list_mpz_clear(v);
@@ -469,6 +550,10 @@ static void test_dual_push1(void)
   }
   list2_double_init_set (list2, list);
   assert(list2_double_equal_p(list, list2));
+  assert(list2_double_equal_p(list, list));
+  list2_double_push_back(list, 17.0);
+  assert(!list2_double_equal_p(list, list2));
+  list2_double_pop_back(NULL, list);
 
   list2_double_reverse(list2);
   for(double e = 0.0; e < 1024.0 ; e += 1.0) {