diff --git a/Viewer/ecflowUI/src/ChangeNotify.cpp b/Viewer/ecflowUI/src/ChangeNotify.cpp
index 2b46a0b60..0b811174d 100644
--- a/Viewer/ecflowUI/src/ChangeNotify.cpp
+++ b/Viewer/ecflowUI/src/ChangeNotify.cpp
@@ -63,6 +63,12 @@ ChangeNotify::ChangeNotify(const std::string& id)
     items[id] = this;
 }
 
+ChangeNotify::~ChangeNotify() {
+    delete data_;
+    delete model_;
+    delete proxyModel_;
+}
+
 ChangeNotifyModel* ChangeNotify::model() const {
     return model_; // proxyModel_;
 }
diff --git a/Viewer/ecflowUI/src/ChangeNotify.hpp b/Viewer/ecflowUI/src/ChangeNotify.hpp
index 13ed2d238..97c51d6a9 100644
--- a/Viewer/ecflowUI/src/ChangeNotify.hpp
+++ b/Viewer/ecflowUI/src/ChangeNotify.hpp
@@ -31,6 +31,7 @@ class ChangeNotify : public VPropertyObserver {
     explicit ChangeNotify(const std::string& id);
     ChangeNotify(const ChangeNotify&)            = delete;
     ChangeNotify& operator=(const ChangeNotify&) = delete;
+    ~ChangeNotify() override;
 
     const std::string& id() const { return id_; }
     VNodeList* data() const { return data_; }
diff --git a/Viewer/ecflowUI/src/InfoPresenter.hpp b/Viewer/ecflowUI/src/InfoPresenter.hpp
index e9cc8c3af..b88a1b6a1 100644
--- a/Viewer/ecflowUI/src/InfoPresenter.hpp
+++ b/Viewer/ecflowUI/src/InfoPresenter.hpp
@@ -25,7 +25,7 @@ class VReply;
 class InfoPresenter {
 public:
     InfoPresenter()          = default;
-    virtual ~InfoPresenter() = default;
+    virtual ~InfoPresenter();
     virtual void infoReady(VReply*) {}
     virtual void infoFailed(VReply*) {}
     virtual void infoProgress(VReply*) {}
diff --git a/Viewer/ecflowUI/src/InfoProvider.cpp b/Viewer/ecflowUI/src/InfoProvider.cpp
index 901fb7144..10284e016 100644
--- a/Viewer/ecflowUI/src/InfoProvider.cpp
+++ b/Viewer/ecflowUI/src/InfoProvider.cpp
@@ -21,6 +21,12 @@
 #include "ecflow/node/EcfFile.hpp"
 #include "ecflow/node/Submittable.hpp"
 
+InfoPresenter::~InfoPresenter() {
+    // The following takes care of deleting the provider used by this presenter.
+    // The provider is typically created in the ctor of derived class (e.g. WhyItemWidget)
+    delete infoProvider_;
+}
+
 InfoProvider::InfoProvider(InfoPresenter* owner, VTask::Type taskType)
     : owner_(owner),
       reply_(new VReply(this)),
@@ -30,8 +36,8 @@ InfoProvider::InfoProvider(InfoPresenter* owner, VTask::Type taskType)
 }
 
 InfoProvider::~InfoProvider() {
-    delete reply_;
     clearInternal();
+    delete reply_;
 }
 
 void InfoProvider::clearInternal() {
diff --git a/Viewer/ecflowUI/src/InfoProvider.hpp b/Viewer/ecflowUI/src/InfoProvider.hpp
index c5cc22997..a5fb17bd5 100644
--- a/Viewer/ecflowUI/src/InfoProvider.hpp
+++ b/Viewer/ecflowUI/src/InfoProvider.hpp
@@ -24,7 +24,9 @@ class InfoProvider : public VTaskObserver, public VInfoVisitor {
     InfoProvider(InfoPresenter* owner, VTask::Type);
     ~InfoProvider() override;
     InfoProvider(const InfoProvider&)            = delete;
+    InfoProvider(InfoProvider&&)                 = delete;
     InfoProvider& operator=(const InfoProvider&) = delete;
+    InfoProvider& operator=(InfoProvider&&)      = delete;
 
     void info(VInfo_ptr);
     void command(VTask::Type);
diff --git a/Viewer/ecflowUI/src/LogLoadWidget.cpp b/Viewer/ecflowUI/src/LogLoadWidget.cpp
index 769e306c3..394637a1c 100644
--- a/Viewer/ecflowUI/src/LogLoadWidget.cpp
+++ b/Viewer/ecflowUI/src/LogLoadWidget.cpp
@@ -169,7 +169,9 @@ LogLoadWidget::LogLoadWidget(QWidget* /*parent*/) : ui_(new Ui::LogLoadWidget) {
     slotExpandFileInfo(expandSt);
 }
 
-LogLoadWidget::~LogLoadWidget() = default;
+LogLoadWidget::~LogLoadWidget() {
+    delete ui_;
+}
 
 // void LogLoadWidget::initSplitter()
 //{
diff --git a/Viewer/ecflowUI/src/ModelColumn.cpp b/Viewer/ecflowUI/src/ModelColumn.cpp
index 3e792c1c0..8dfe7546c 100644
--- a/Viewer/ecflowUI/src/ModelColumn.cpp
+++ b/Viewer/ecflowUI/src/ModelColumn.cpp
@@ -20,16 +20,56 @@
 #include "VProperty.hpp"
 #include "VSettingsLoader.hpp"
 
-static std::map<std::string, ModelColumn*> defs;
+class ColumnDefinitions {
+public:
+    using storage_t = std::map<std::string, ModelColumn*>;
+
+    ColumnDefinitions(): storage_{} {}
+    ~ColumnDefinitions() {
+        for(auto item: storage_) {
+            delete item.second;
+        }
+    }
+
+    void insert(const std::string& k, ModelColumn* v) {
+        storage_[k] = v;
+    }
+
+    auto find(const std::string& k) const {
+        return storage_.find(k);
+    }
+
+    auto end() {
+        return storage_.end();
+    }
+
+    template <typename F>
+    void for_each(F&& f) {
+        for(auto item: storage_) {
+            f(item.first, item.second);
+        }
+    }
+
+private:
+    storage_t storage_;
+};
+
+static ColumnDefinitions defs;
 
 ModelColumn::ModelColumn(const std::string& id) : id_(id), diagStart_(-1), diagEnd_(-1) {
-    defs[id_] = this;
+    defs.insert(id_, this);
+}
+
+ModelColumn::~ModelColumn() {
+    for(auto && item: items_) {
+        delete item;
+    }
 }
 
 ModelColumn* ModelColumn::def(const std::string& id) {
-    auto it = defs.find(id);
-    if (it != defs.end())
+    if (auto it = defs.find(id); it != defs.end()) {
         return it->second;
+    }
     return nullptr;
 }
 
@@ -211,6 +251,9 @@ void ModelColumn::load(VProperty* group) {
     Q_ASSERT(group);
 
     auto* m = new ModelColumn(group->strName());
+    // Attention: Each ModelColumn object self-registers in `defs`!
+    //            This means that the newly created object will live until `defs` (with static allocation) is released.
+
     for (int i = 0; i < group->children().size(); i++) {
         VProperty* p = group->children().at(i);
         m->loadItem(p);
@@ -222,9 +265,7 @@ void ModelColumn::load(VProperty* group) {
 
 // Called via VSettingsLoader after the users settings are read
 void ModelColumn::loadSettings() {
-    for (auto& def : defs) {
-        def.second->loadUserSettings();
-    }
+    defs.for_each([](auto&& k, auto&& v){v->loadUserSettings();});
 }
 
 // Load user defined settings
diff --git a/Viewer/ecflowUI/src/ModelColumn.hpp b/Viewer/ecflowUI/src/ModelColumn.hpp
index c473375ef..ce4bb3e62 100644
--- a/Viewer/ecflowUI/src/ModelColumn.hpp
+++ b/Viewer/ecflowUI/src/ModelColumn.hpp
@@ -42,6 +42,7 @@ class ModelColumn : public QObject {
     Q_OBJECT
 public:
     explicit ModelColumn(const std::string& id);
+    ~ModelColumn() override;
 
     int count() const { return items_.size(); }
     int indexOf(QString) const;
diff --git a/Viewer/ecflowUI/src/NodeQuery.cpp b/Viewer/ecflowUI/src/NodeQuery.cpp
index 337474a3e..d3b04ffc1 100644
--- a/Viewer/ecflowUI/src/NodeQuery.cpp
+++ b/Viewer/ecflowUI/src/NodeQuery.cpp
@@ -77,6 +77,7 @@ NodeQuery::NodeQuery(const std::string& name, bool ignoreMaxNum)
 
 NodeQuery::~NodeQuery() {
     qDeleteAll(options_);
+    qDeleteAll(attrGroup_);
 }
 
 NodeQuery* NodeQuery::clone() {
diff --git a/Viewer/ecflowUI/src/NodeQuery.hpp b/Viewer/ecflowUI/src/NodeQuery.hpp
index 29b50d16c..b95f6fd02 100644
--- a/Viewer/ecflowUI/src/NodeQuery.hpp
+++ b/Viewer/ecflowUI/src/NodeQuery.hpp
@@ -33,6 +33,7 @@ class NodeQueryAttrGroup {
         : name_(name),
           types_(types),
           options_(options) {}
+    virtual ~NodeQueryAttrGroup() = default;
 
     QString name() const { return name_; }
     virtual bool hasType(VAttributeType* t) const { return types_.contains(t); }
@@ -41,14 +42,15 @@ class NodeQueryAttrGroup {
 
 protected:
     QString name_;
-    QList<VAttributeType*> types_;
-    QList<NodeQueryOption*> options_;
+    QList<VAttributeType*> types_; // This is a non-owning container
+    QList<NodeQueryOption*> options_; // This is a non-owning container 
 };
 
 class NodeQueryVarAttrGroup : public NodeQueryAttrGroup {
 public:
     NodeQueryVarAttrGroup(QString name, QList<VAttributeType*> types, QList<NodeQueryOption*> options)
         : NodeQueryAttrGroup(name, types, options) {}
+    ~NodeQueryVarAttrGroup() override = default;
 
     bool hasType(VAttributeType*) const override;
 };
diff --git a/Viewer/ecflowUI/src/OutputDirWidget.cpp b/Viewer/ecflowUI/src/OutputDirWidget.cpp
index 40a487f04..6a1e3584e 100644
--- a/Viewer/ecflowUI/src/OutputDirWidget.cpp
+++ b/Viewer/ecflowUI/src/OutputDirWidget.cpp
@@ -370,6 +370,10 @@ OutputDirWidget::OutputDirWidget(QWidget* parent) : QWidget(parent), ui_(new Ui:
     transitionTo(new DirWidgetEmptyState(this, nullptr));
 }
 
+OutputDirWidget::~OutputDirWidget() {
+    delete ui_;
+}
+
 // must be called externally
 void OutputDirWidget::showIt(bool st) {
     if (st) {
diff --git a/Viewer/ecflowUI/src/OutputDirWidget.hpp b/Viewer/ecflowUI/src/OutputDirWidget.hpp
index b13678c9b..93b38a8eb 100644
--- a/Viewer/ecflowUI/src/OutputDirWidget.hpp
+++ b/Viewer/ecflowUI/src/OutputDirWidget.hpp
@@ -43,6 +43,7 @@ class OutputDirWidget : public QWidget {
 
 public:
     explicit OutputDirWidget(QWidget* parent);
+    ~OutputDirWidget() override;
 
     void clear();
     void load(VReply* reply, const std::string& joboutFile);
diff --git a/Viewer/ecflowUI/src/OutputFetchInfo.cpp b/Viewer/ecflowUI/src/OutputFetchInfo.cpp
index c33986c16..83b07b377 100644
--- a/Viewer/ecflowUI/src/OutputFetchInfo.cpp
+++ b/Viewer/ecflowUI/src/OutputFetchInfo.cpp
@@ -45,6 +45,10 @@ OutputFetchInfo::OutputFetchInfo(QWidget* parent) : QWidget(parent), ui_(new Ui:
     connect(bGroup_, SIGNAL(buttonClicked(QAbstractButton*)), this, SLOT(buttonClicked(QAbstractButton*)));
 }
 
+OutputFetchInfo::~OutputFetchInfo() {
+    delete ui_;
+}
+
 void OutputFetchInfo::buttonClicked(QAbstractButton* b) {
     ui_->stackedWidget->setCurrentIndex((b == ui_->infoTb) ? 0 : 1);
 }
diff --git a/Viewer/ecflowUI/src/OutputFetchInfo.hpp b/Viewer/ecflowUI/src/OutputFetchInfo.hpp
index c063bc56c..ee1e83aab 100644
--- a/Viewer/ecflowUI/src/OutputFetchInfo.hpp
+++ b/Viewer/ecflowUI/src/OutputFetchInfo.hpp
@@ -30,6 +30,8 @@ class OutputFetchInfo : public QWidget {
     Q_OBJECT
 public:
     explicit OutputFetchInfo(QWidget* parent);
+    ~OutputFetchInfo() override;
+
     void clearInfo();
     void setInfo(VReply*, VInfo_ptr info = nullptr);
     void setError(QString);
diff --git a/Viewer/ecflowUI/src/PlainTextWidget.cpp b/Viewer/ecflowUI/src/PlainTextWidget.cpp
index 20cf30125..8df899ea0 100644
--- a/Viewer/ecflowUI/src/PlainTextWidget.cpp
+++ b/Viewer/ecflowUI/src/PlainTextWidget.cpp
@@ -33,6 +33,10 @@ PlainTextWidget::PlainTextWidget(QWidget* /*parent*/) : ui_(new Ui::PlainTextWid
     connect(ui_->fontSizeDownTb, SIGNAL(clicked()), this, SLOT(slotFontSizeDown()));
 }
 
+PlainTextWidget::~PlainTextWidget() {
+    delete ui_;
+}
+
 void PlainTextWidget::setPlainText(QString t) {
     ui_->textEdit->setPlainText(t);
 }
diff --git a/Viewer/ecflowUI/src/PlainTextWidget.hpp b/Viewer/ecflowUI/src/PlainTextWidget.hpp
index 50840cac3..88c5bb625 100644
--- a/Viewer/ecflowUI/src/PlainTextWidget.hpp
+++ b/Viewer/ecflowUI/src/PlainTextWidget.hpp
@@ -22,7 +22,7 @@ class PlainTextWidget : public QWidget {
 
 public:
     explicit PlainTextWidget(QWidget* parent = nullptr);
-    ~PlainTextWidget() override = default;
+    ~PlainTextWidget() override;
 
     void setPlainText(QString);
     void setTitle(QString);
diff --git a/Viewer/ecflowUI/src/TimelineView.cpp b/Viewer/ecflowUI/src/TimelineView.cpp
index 6fb651724..13faf68d8 100644
--- a/Viewer/ecflowUI/src/TimelineView.cpp
+++ b/Viewer/ecflowUI/src/TimelineView.cpp
@@ -73,7 +73,9 @@ TimelineDelegate::TimelineDelegate(TimelineModel* model, QWidget* parent)
     updateSettings();
 }
 
-TimelineDelegate::~TimelineDelegate() = default;
+TimelineDelegate::~TimelineDelegate() {
+    delete prop_;
+}
 
 void TimelineDelegate::notifyChange(VProperty*) {
     updateSettings();
diff --git a/Viewer/ecflowUI/src/TimelineWidget.cpp b/Viewer/ecflowUI/src/TimelineWidget.cpp
index 1c898e0c2..ad087d78d 100644
--- a/Viewer/ecflowUI/src/TimelineWidget.cpp
+++ b/Viewer/ecflowUI/src/TimelineWidget.cpp
@@ -222,8 +222,8 @@ TimelineWidget::TimelineWidget(QWidget* /*parent*/)
 }
 
 TimelineWidget::~TimelineWidget() {
-    if (data_)
-        delete data_;
+    delete data_;
+    delete ui_;
 }
 
 // a complete clear
diff --git a/Viewer/ecflowUI/src/TreeNodeWidget.cpp b/Viewer/ecflowUI/src/TreeNodeWidget.cpp
index 8fbdb2553..ed7e10c42 100644
--- a/Viewer/ecflowUI/src/TreeNodeWidget.cpp
+++ b/Viewer/ecflowUI/src/TreeNodeWidget.cpp
@@ -86,7 +86,11 @@ TreeNodeWidget::TreeNodeWidget(ServerFilter* serverFilter, QWidget* parent)
     WidgetNameProvider::nameChildren(this);
 }
 
-TreeNodeWidget::~TreeNodeWidget() = default;
+TreeNodeWidget::~TreeNodeWidget() {
+    delete stateFilterMenu_;
+    delete attrFilterMenu_;
+    delete iconFilterMenu_;
+}
 
 void TreeNodeWidget::setViewLayoutMode(TreeNodeWidget::ViewLayoutMode mode) {
     if (view_ && viewLayoutMode_ == mode)
diff --git a/Viewer/ecflowUI/src/TriggerGraphWidget.cpp b/Viewer/ecflowUI/src/TriggerGraphWidget.cpp
index 909c1c910..c3747b3cd 100644
--- a/Viewer/ecflowUI/src/TriggerGraphWidget.cpp
+++ b/Viewer/ecflowUI/src/TriggerGraphWidget.cpp
@@ -47,6 +47,7 @@ TriggerGraphWidget::TriggerGraphWidget(QWidget* parent) : QWidget(parent), ui_(n
 
 TriggerGraphWidget::~TriggerGraphWidget() {
     clear();
+    delete ui_;
 }
 
 void TriggerGraphWidget::clear(bool keepConfig) {
diff --git a/Viewer/ecflowUI/src/VConfigLoader.cpp b/Viewer/ecflowUI/src/VConfigLoader.cpp
index b34710464..07dab5f34 100644
--- a/Viewer/ecflowUI/src/VConfigLoader.cpp
+++ b/Viewer/ecflowUI/src/VConfigLoader.cpp
@@ -11,14 +11,16 @@
 #include "VConfigLoader.hpp"
 
 #include <map>
+#include <memory>
 
 using Map = std::multimap<std::string, VConfigLoader*>;
 
-static Map* makers = nullptr;
+static std::unique_ptr<Map> makers = nullptr;
 
 VConfigLoader::VConfigLoader(const std::string& name) {
-    if (makers == nullptr)
-        makers = new Map();
+    if (!makers) {
+        makers = std::make_unique<Map>();
+    }
 
     makers->insert(Map::value_type(name, this));
 }
diff --git a/Viewer/ecflowUI/src/WhyItemWidget.cpp b/Viewer/ecflowUI/src/WhyItemWidget.cpp
index 14971e0b0..e2ac311b7 100644
--- a/Viewer/ecflowUI/src/WhyItemWidget.cpp
+++ b/Viewer/ecflowUI/src/WhyItemWidget.cpp
@@ -39,7 +39,7 @@ WhyItemWidget::WhyItemWidget(QWidget* parent) : HtmlItemWidget(parent) {
     fileLabel_->hide();
 
     // Will be used for ECFLOW-901
-    infoProvider_ = new WhyProvider(this);
+    infoProvider_ = new WhyProvider(this); // populating InfoPresenter::infoProvider_, with the deletion later handled by InfoPresenter itself
 
     textEdit_->setProperty("trigger", "1");
     textEdit_->setFontProperty(VConfig::instance()->find("panel.why.font"));
diff --git a/Viewer/ecflowUI/src/WhyItemWidget.hpp b/Viewer/ecflowUI/src/WhyItemWidget.hpp
index f70614768..6f6e74fb9 100644
--- a/Viewer/ecflowUI/src/WhyItemWidget.hpp
+++ b/Viewer/ecflowUI/src/WhyItemWidget.hpp
@@ -24,8 +24,13 @@ class WhyItemWidget : public HtmlItemWidget, public InfoPanelItem {
 
 public:
     explicit WhyItemWidget(QWidget* parent = nullptr);
+    WhyItemWidget(const WhyItemWidget&) = delete;
+    WhyItemWidget(WhyItemWidget&&) = delete;
     ~WhyItemWidget() override;
 
+    WhyItemWidget& operator=(const WhyItemWidget&) = delete;
+    WhyItemWidget& operator=(WhyItemWidget&&) = delete;
+
     void reload(VInfo_ptr) override;
     QWidget* realWidget() override;
     void clearContents() override;
diff --git a/Viewer/libViewer/src/IconProvider.cpp b/Viewer/libViewer/src/IconProvider.cpp
index 3a04d750e..bae92b905 100644
--- a/Viewer/libViewer/src/IconProvider.cpp
+++ b/Viewer/libViewer/src/IconProvider.cpp
@@ -108,6 +108,17 @@ QPixmap UnknownIconItem::unknown(int /*size*/) {
 
 IconProvider::IconProvider() = default;
 
+IconProvider::~IconProvider() {
+    // Important!
+    //
+    // The life time of the singleton instance 'iconProvider' is used to manage the life time of loaded Icons.
+    // This means that when the application closes, after main() has finished, the destruction of the instance clears the Icons.
+    //
+    for(auto icon : icons_) {
+        delete icon.second;
+    }
+}
+
 QString IconProvider::path(int id) {
     auto it = iconsById_.find(id);
     if (it != iconsById_.end())
diff --git a/Viewer/libViewer/src/IconProvider.hpp b/Viewer/libViewer/src/IconProvider.hpp
index 0e4c7a601..16557fa6b 100644
--- a/Viewer/libViewer/src/IconProvider.hpp
+++ b/Viewer/libViewer/src/IconProvider.hpp
@@ -45,6 +45,7 @@ class UnknownIconItem : public IconItem {
 class IconProvider {
 public:
     IconProvider();
+    ~IconProvider();
 
     static int add(QString path, QString name);
 
diff --git a/libs/client/src/ecflow/client/ClientOptions.hpp b/libs/client/src/ecflow/client/ClientOptions.hpp
index 18a218e6f..97a636a77 100644
--- a/libs/client/src/ecflow/client/ClientOptions.hpp
+++ b/libs/client/src/ecflow/client/ClientOptions.hpp
@@ -30,11 +30,12 @@ class CommandLine;
 
 class ClientOptions {
 public:
-    ClientOptions(const ClientOptions&)                  = delete;
-    const ClientOptions& operator=(const ClientOptions&) = delete;
-
     /// Will create command register, & ask each cmd to describe their arguments
     ClientOptions();
+    ClientOptions(const ClientOptions&)            = delete;
+    ClientOptions(ClientOptions&&)                 = delete;
+    ClientOptions& operator=(const ClientOptions&) = delete;
+    ClientOptions& operator=(ClientOptions&&)      = delete;
     ~ClientOptions();
 
     /// parse the arguments and create the client request that is to be sent
diff --git a/libs/node/src/ecflow/node/ExprDuplicate.cpp b/libs/node/src/ecflow/node/ExprDuplicate.cpp
index d0f82eb4d..a4eab4090 100644
--- a/libs/node/src/ecflow/node/ExprDuplicate.cpp
+++ b/libs/node/src/ecflow/node/ExprDuplicate.cpp
@@ -16,32 +16,24 @@
 #include "ecflow/core/Ecf.hpp"
 #include "ecflow/node/ExprAst.hpp"
 
-using namespace std;
+using expression_cache_t = std::unordered_map<std::string, std::unique_ptr<AstTop>>;
+
+static expression_cache_t duplicate_expr;
 
-static std::unordered_map<std::string, AstTop*> duplicate_expr;
-typedef std::unordered_map<std::string, AstTop*> my_map;
 
 ExprDuplicate::~ExprDuplicate() {
-    // cout << "ExprDuplicate::~ExprDuplicate: server(" << Ecf::server() << ") " << duplicate_expr.size() << "
-    // *****************************************************************\n";
-    for (my_map::value_type i : duplicate_expr) {
-        // cout << " deleting: " << i.first << " :" << i.second << "\n";
-        delete i.second;
-        i.second = NULL;
-    }
     duplicate_expr.clear();
 }
 
 void ExprDuplicate::dump(const std::string& msg) {
-    cout << "ExprDuplicate::dump server(" << Ecf::server() << ") " << msg << "\n";
-    for (const my_map::value_type& i : duplicate_expr) {
-        cout << "   " << i.first << " :" << i.second << "\n";
+    std::cout << "ExprDuplicate::dump server(" << Ecf::server() << ") " << msg << "\n";
+    for (const auto& i : duplicate_expr) {
+        std::cout << "   " << i.first << " :" << i.second.get() << "\n";
     }
 }
 
 std::unique_ptr<AstTop> ExprDuplicate::find(const std::string& expr) {
-    my_map::const_iterator it = duplicate_expr.find(expr);
-    if (it != duplicate_expr.end()) {
+    if (auto it = duplicate_expr.find(expr); it != duplicate_expr.end()) {
         return std::unique_ptr<AstTop>((*it).second->clone());
     }
     return std::unique_ptr<AstTop>();
@@ -49,9 +41,6 @@ std::unique_ptr<AstTop> ExprDuplicate::find(const std::string& expr) {
 
 void ExprDuplicate::add(const std::string& expr, AstTop* ast) {
     assert(!expr.empty() && ast);
-    AstTop* clone = ast->clone();
-    duplicate_expr.insert(std::make_pair(expr, clone));
-
-    // cout << "ExprDuplicate::add: server(" << Ecf::server() << ") " << expr << " :" << clone << "   " <<
-    // duplicate_expr.size() << "\n";
+    auto clone = std::unique_ptr<AstTop>(ast->clone());
+    duplicate_expr.emplace(expr, std::move(clone));
 }