diff --git a/density/include/density_sketch_impl.hpp b/density/include/density_sketch_impl.hpp
index 1144814a..a5a5bc0f 100755
--- a/density/include/density_sketch_impl.hpp
+++ b/density/include/density_sketch_impl.hpp
@@ -144,7 +144,7 @@ void density_sketch<T, K, A>::compact_level(unsigned height) {
   auto& level = levels_[height];
   std::vector<bool> bits(level.size());
   bits[0] = random_utils::random_bit();
-  std::random_shuffle(level.begin(), level.end());
+  std::shuffle(level.begin(), level.end(), random_utils::rand);
   for (unsigned i = 1; i < level.size(); ++i) {
     T delta = 0;
     for (unsigned j = 0; j < i; ++j) {
diff --git a/kll/include/kll_helper_impl.hpp b/kll/include/kll_helper_impl.hpp
index e763c575..bb92bdc7 100644
--- a/kll/include/kll_helper_impl.hpp
+++ b/kll/include/kll_helper_impl.hpp
@@ -230,7 +230,8 @@ kll_helper::compress_result kll_helper::general_compress(uint16_t k, uint8_t m,
       // move level over as is
       // make sure we are not moving data upwards
       if (raw_beg < out_levels[current_level]) throw std::logic_error("wrong move");
-      std::move(items + raw_beg, items + raw_lim, items + out_levels[current_level]);
+      if (raw_beg != out_levels[current_level])
+        std::move(items + raw_beg, items + raw_lim, items + out_levels[current_level]);
       out_levels[current_level + 1] = out_levels[current_level] + raw_pop;
     } else {
       // The sketch is too full AND this level is too full, so we compact it
@@ -243,7 +244,8 @@ kll_helper::compress_result kll_helper::general_compress(uint16_t k, uint8_t m,
       const auto half_adj_pop = adj_pop / 2;
 
       if (odd_pop) { // move one guy over
-        items[out_levels[current_level]] = std::move(items[raw_beg]);
+        if (out_levels[current_level] != raw_beg)
+          items[out_levels[current_level]] = std::move(items[raw_beg]);
         out_levels[current_level + 1] = out_levels[current_level] + 1;
       } else { // even number of items
         out_levels[current_level + 1] = out_levels[current_level];
diff --git a/sampling/include/ebpps_sample_impl.hpp b/sampling/include/ebpps_sample_impl.hpp
index afa4dcac..f379841b 100644
--- a/sampling/include/ebpps_sample_impl.hpp
+++ b/sampling/include/ebpps_sample_impl.hpp
@@ -178,7 +178,11 @@ string<A> ebpps_sample<T ,A>::to_string() const {
   uint32_t idx = 0;
   for (const T& item : data_)
     oss << "\t" << idx++ << ":\t" << item << std::endl;
-  oss << "   partial: " << (bool(partial_item_) ? (*partial_item_) : "NULL") << std::endl;
+  oss << "   partial: ";
+  if (bool(partial_item_))
+    oss << (*partial_item_) << std::endl;
+  else
+    oss << "NULL" << std::endl;
 
   return oss.str();
 }
diff --git a/version.cfg.in b/version.cfg.in
index 57751565..a1ef0cae 100644
--- a/version.cfg.in
+++ b/version.cfg.in
@@ -1 +1 @@
-4.2.@DT@.@HHMM@
+5.0.2