diff --git a/src/resultset.h b/src/resultset.h
--- a/src/resultset.h
+++ b/src/resultset.h
@@ -162,16 +162,16 @@
 
         reference operator[](difference_type n) const;
 
-        friend bool operator==(const const_iterator &left, const const_iterator &right);
-        friend bool operator!=(const const_iterator &left, const const_iterator &right);
+        KACTIVITIESSTATS_EXPORT friend bool operator==(const const_iterator &left, const const_iterator &right);
+        KACTIVITIESSTATS_EXPORT friend bool operator!=(const const_iterator &left, const const_iterator &right);
 
-        friend bool operator<(const const_iterator &left, const const_iterator &right);
-        friend bool operator>(const const_iterator &left, const const_iterator &right);
+        KACTIVITIESSTATS_EXPORT friend bool operator<(const const_iterator &left, const const_iterator &right);
+        KACTIVITIESSTATS_EXPORT friend bool operator>(const const_iterator &left, const const_iterator &right);
 
-        friend bool operator<=(const const_iterator &left, const const_iterator &right);
-        friend bool operator>=(const const_iterator &left, const const_iterator &right);
+        KACTIVITIESSTATS_EXPORT friend bool operator<=(const const_iterator &left, const const_iterator &right);
+        KACTIVITIESSTATS_EXPORT friend bool operator>=(const const_iterator &left, const const_iterator &right);
 
-        friend difference_type operator-(const const_iterator &left, const const_iterator &right);
+        KACTIVITIESSTATS_EXPORT friend difference_type operator-(const const_iterator &left, const const_iterator &right);
 
     private:
         const_iterator(const ResultSet *resultSet, int currentRow);
diff --git a/src/resultset_iterator.cpp b/src/resultset_iterator.cpp
--- a/src/resultset_iterator.cpp
+++ b/src/resultset_iterator.cpp
@@ -72,10 +72,9 @@
     friend void swap(ResultSet_IteratorPrivate &left,
                      ResultSet_IteratorPrivate &right)
     {
-        using namespace std;
-        swap(left.resultSet,    right.resultSet);
-        swap(left.currentRow,   right.currentRow);
-        swap(left.currentValue, right.currentValue);
+        std::swap(left.resultSet,    right.resultSet);
+        std::swap(left.currentRow,   right.currentRow);
+        std::swap(left.currentValue, right.currentValue);
     }
 
     bool operator==(const ResultSet_IteratorPrivate &other) const
diff --git a/src/utils/lazy_val.h b/src/utils/lazy_val.h
--- a/src/utils/lazy_val.h
+++ b/src/utils/lazy_val.h
@@ -38,7 +38,7 @@
     mutable bool valueRetrieved;
 
 public:
-    operator decltype(_f()) () const
+    operator auto() const -> decltype(_f())
     {
         if (!valueRetrieved) {
             valueRetrieved = true;