diff --git a/src/departures_gui.cpp b/src/departures_gui.cpp
index 699bd16de8..4f24b4bf98 100644
--- a/src/departures_gui.cpp
+++ b/src/departures_gui.cpp
@@ -182,7 +182,7 @@ public:
 		this->DeleteDeparturesList(this->arrivals);
 	}
 
-	virtual void UpdateWidgetSize(int widget, Dimension *size, const Dimension &padding, Dimension *fill, Dimension *resize)
+	virtual void UpdateWidgetSize(int widget, Dimension *size, const Dimension &padding, Dimension *fill, Dimension *resize) override
 	{
 		switch (widget) {
 			case WID_DB_LIST:
@@ -192,7 +192,7 @@ public:
 		}
 	}
 
-	virtual void SetStringParameters(int widget) const
+	virtual void SetStringParameters(int widget) const override
 	{
 		if (widget == WID_DB_CAPTION) {
 			const Station *st = Station::Get(this->station);
@@ -200,7 +200,7 @@ public:
 		}
 	}
 
-	virtual void OnClick(Point pt, int widget, int click_count)
+	virtual void OnClick(Point pt, int widget, int click_count) override
 	{
 		switch (widget) {
 			case WID_DB_SHOW_TRAINS:   // Show trains to this station
@@ -374,7 +374,7 @@ public:
 		}
 	}
 
-	virtual void OnPaint()
+	virtual void OnPaint() override
 	{
 		if (Twaypoint || _settings_client.gui.departure_show_both) {
 			this->DisableWidget(WID_DB_SHOW_ARRS);
@@ -388,7 +388,7 @@ public:
 		this->DrawWidgets();
 	}
 
-	virtual void DrawWidget(const Rect &r, int widget) const
+	virtual void DrawWidget(const Rect &r, int widget) const override
 	{
 		switch (widget) {
 			case WID_DB_LIST:
@@ -397,7 +397,7 @@ public:
 		}
 	}
 
-	virtual void OnResize()
+	virtual void OnResize() override
 	{
 		this->vscroll->SetCapacityFromWidget(this, WID_DB_LIST);
 		this->GetWidget<NWidgetCore>(WID_DB_LIST)->widget_data = (this->vscroll->GetCapacity() << MAT_ROW_START) + (1 << MAT_COL_START);
diff --git a/src/main_gui.cpp b/src/main_gui.cpp
index 112b9f3a4a..562aa9e2ca 100644
--- a/src/main_gui.cpp
+++ b/src/main_gui.cpp
@@ -465,7 +465,7 @@ struct MainWindow : Window
 		InvalidateWindowData(WC_MAIN_TOOLBAR, 0, data, true);
 	}
 
-	virtual void OnMouseOver(Point pt, int widget)
+	virtual void OnMouseOver(Point pt, int widget) override
 	{
 		if (pt.x != -1 && _game_mode != GM_MENU && (_mouse_hovering || _settings_client.gui.hover_delay_ms == 0)) {
 			/* Show tooltip with last month production or town name */
diff --git a/src/os/unix/crashlog_unix.cpp b/src/os/unix/crashlog_unix.cpp
index 031ab95ca6..27c7b85ecd 100644
--- a/src/os/unix/crashlog_unix.cpp
+++ b/src/os/unix/crashlog_unix.cpp
@@ -247,7 +247,7 @@ class CrashLogUnix : public CrashLog {
 	 *
 	 * Also log GDB information if available
 	 */
-	char *LogRegisters(char *buffer, const char *last) const
+	char *LogRegisters(char *buffer, const char *last) const override
 	{
 		buffer = LogGdbInfo(buffer, last);
 
@@ -490,7 +490,7 @@ class CrashLogUnix : public CrashLog {
 	 * This is a wrapper around the generic LogScopeInfo function which sets
 	 * up a signal handler to catch any SIGSEGVs which may occur due to invalid data
 	 */
-	/* virtual */ char *LogScopeInfo(char *buffer, const char *last) const
+	/* virtual */ char *LogScopeInfo(char *buffer, const char *last) const override
 	{
 		logStacktraceSavedBuffer = buffer;
 
diff --git a/src/schdispatch_gui.cpp b/src/schdispatch_gui.cpp
index 57fe91ea2c..81c4219c5b 100644
--- a/src/schdispatch_gui.cpp
+++ b/src/schdispatch_gui.cpp
@@ -175,7 +175,7 @@ struct SchdispatchWindow : Window {
 	uint flag_width;
 	uint flag_height;
 
-	virtual void UpdateWidgetSize(int widget, Dimension *size, const Dimension &padding, Dimension *fill, Dimension *resize)
+	virtual void UpdateWidgetSize(int widget, Dimension *size, const Dimension &padding, Dimension *fill, Dimension *resize) override
 	{
 		switch (widget) {
 			case WID_SCHDISPATCH_MATRIX: {
@@ -223,7 +223,7 @@ struct SchdispatchWindow : Window {
 	 * @param data Information about the changed data.
 	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
 	 */
-	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true) override
 	{
 		switch (data) {
 			case VIWD_MODIFY_ORDERS:
@@ -233,7 +233,7 @@ struct SchdispatchWindow : Window {
 		}
 	}
 
-	virtual void OnPaint()
+	virtual void OnPaint() override
 	{
 		const Vehicle *v = this->vehicle;
 		CountItem();
@@ -256,7 +256,7 @@ struct SchdispatchWindow : Window {
 		this->DrawWidgets();
 	}
 
-	virtual void SetStringParameters(int widget) const
+	virtual void SetStringParameters(int widget) const override
 	{
 		switch (widget) {
 			case WID_SCHDISPATCH_CAPTION: SetDParam(0, this->vehicle->index); break;
@@ -296,7 +296,7 @@ struct SchdispatchWindow : Window {
 		}
 	}
 
-	virtual void DrawWidget(const Rect &r, int widget) const
+	virtual void DrawWidget(const Rect &r, int widget) const override
 	{
 		const Vehicle *v = this->vehicle;
 
@@ -400,7 +400,7 @@ struct SchdispatchWindow : Window {
 		}
 	}
 
-	virtual void OnClick(Point pt, int widget, int click_count)
+	virtual void OnClick(Point pt, int widget, int click_count) override
 	{
 		const Vehicle *v = this->vehicle;
 
@@ -468,7 +468,7 @@ struct SchdispatchWindow : Window {
 		this->SetDirty();
 	}
 
-	virtual void OnQueryTextFinished(char *str)
+	virtual void OnQueryTextFinished(char *str) override
 	{
 		if (str == nullptr) return;
 		const Vehicle *v = this->vehicle;
@@ -541,14 +541,14 @@ struct SchdispatchWindow : Window {
 		this->SetDirty();
 	}
 
-	virtual void OnResize()
+	virtual void OnResize() override
 	{
 		this->vscroll->SetCapacityFromWidget(this, WID_SCHDISPATCH_MATRIX);
 		NWidgetCore *nwi = this->GetWidget<NWidgetCore>(WID_SCHDISPATCH_MATRIX);
 		this->num_columns = nwi->current_x / nwi->resize_x;
 	}
 
-	virtual void OnFocus(Window *previously_focused_window)
+	virtual void OnFocus(Window *previously_focused_window) override
 	{
 		if (HasFocusedVehicleChanged(this->window_number, previously_focused_window)) {
 			MarkAllRoutePathsDirty(this->vehicle);
diff --git a/src/table/newgrf_debug_data.h b/src/table/newgrf_debug_data.h
index 6abf2391e7..61b038e2c6 100644
--- a/src/table/newgrf_debug_data.h
+++ b/src/table/newgrf_debug_data.h
@@ -84,7 +84,7 @@ class NIHVehicle : public NIHelper {
 		return ro.GetScope(VSG_SCOPE_SELF)->GetVariable(var, param, avail);
 	}
 
-	/* virtual */ void ExtraInfo(uint index, std::function<void(const char *)> print) const
+	/* virtual */ void ExtraInfo(uint index, std::function<void(const char *)> print) const override
 	{
 		char buffer[1024];
 		Vehicle *v = Vehicle::Get(index);
diff --git a/src/timetable_gui.cpp b/src/timetable_gui.cpp
index 48f4246c7c..50c2d0b2b8 100644
--- a/src/timetable_gui.cpp
+++ b/src/timetable_gui.cpp
@@ -970,7 +970,7 @@ struct TimetableWindow : Window {
 		this->GetWidget<NWidgetStacked>(WID_VT_SEL_SHARED)->SetDisplayedPlane(this->vehicle->owner == _local_company && _ctrl_pressed ? 1 : 0);
 	}
 
-	virtual void OnFocus(Window *previously_focused_window)
+	virtual void OnFocus(Window *previously_focused_window) override
 	{
 		if (HasFocusedVehicleChanged(this->window_number, previously_focused_window)) {
 			MarkAllRoutePathsDirty(this->vehicle);
@@ -978,7 +978,7 @@ struct TimetableWindow : Window {
 		}
 	}
 
-	virtual void OnFocusLost(Window *newly_focused_window)
+	virtual void OnFocusLost(Window *newly_focused_window) override
 	{
 		if (HasFocusedVehicleChanged(this->window_number, newly_focused_window)) {
 			MarkAllRoutePathsDirty(this->vehicle);
diff --git a/src/town_gui.cpp b/src/town_gui.cpp
index 8416b30437..28290e05ea 100644
--- a/src/town_gui.cpp
+++ b/src/town_gui.cpp
@@ -1463,7 +1463,7 @@ public:
 		}
 	}
 
-	virtual void SetStringParameters(int widget) const
+	virtual void SetStringParameters(int widget) const override
 	{
 		if (widget == WID_HP_CAPTION) {
 			if (this->house_list.NumHouseSets() == 1) SetDParamStr(0, this->house_list.GetNameOfHouseSet(0));
@@ -1576,7 +1576,7 @@ public:
 		}
 	}
 
-	virtual void UpdateWidgetSize(int widget, Dimension *size, const Dimension &padding, Dimension *fill, Dimension *resize)
+	virtual void UpdateWidgetSize(int widget, Dimension *size, const Dimension &padding, Dimension *fill, Dimension *resize) override
 	{
 		switch (widget) {
 			case WID_HP_HOUSE_SETS: {
@@ -1652,7 +1652,7 @@ public:
 		}
 	}
 
-	virtual void DrawWidget(const Rect &r, int widget) const
+	virtual void DrawWidget(const Rect &r, int widget) const override
 	{
 		switch (GB(widget, 0, 16)) {
 			case WID_HP_HOUSE_SETS: {
@@ -1687,7 +1687,7 @@ public:
 		}
 	}
 
-	virtual void OnClick(Point pt, int widget, int click_count)
+	virtual void OnClick(Point pt, int widget, int click_count) override
 	{
 		switch (GB(widget, 0, 16)) {
 			case WID_HP_HOUSE_SETS: {
diff --git a/src/tracerestrict_gui.cpp b/src/tracerestrict_gui.cpp
index 00900c17f5..77bd34907a 100644
--- a/src/tracerestrict_gui.cpp
+++ b/src/tracerestrict_gui.cpp
@@ -2974,7 +2974,7 @@ public:
 		*this->sorting = this->vehicles.GetListing();
 	}
 
-	virtual void UpdateWidgetSize(int widget, Dimension *size, const Dimension &padding, Dimension *fill, Dimension *resize)
+	virtual void UpdateWidgetSize(int widget, Dimension *size, const Dimension &padding, Dimension *fill, Dimension *resize) override
 	{
 		switch (widget) {
 			case WID_TRSL_LIST_SLOTS: {
@@ -3021,7 +3021,7 @@ public:
 	 * @param data Information about the changed data.
 	 * @param gui_scope Whether the call is done from GUI scope. You may not do everything when not in GUI scope. See #InvalidateWindowData() for details.
 	 */
-	virtual void OnInvalidateData(int data = 0, bool gui_scope = true)
+	virtual void OnInvalidateData(int data = 0, bool gui_scope = true) override
 	{
 		if (data == 0) {
 			/* This needs to be done in command-scope to enforce rebuilding before resorting invalid data */
@@ -3048,7 +3048,7 @@ public:
 		this->SetDirty();
 	}
 
-	virtual void SetStringParameters(int widget) const
+	virtual void SetStringParameters(int widget) const override
 	{
 		switch (widget) {
 			case WID_TRSL_FILTER_BY_CARGO:
@@ -3057,7 +3057,7 @@ public:
 		}
 	}
 
-	virtual void OnPaint()
+	virtual void OnPaint() override
 	{
 		/* If we select the all vehicles, this->list will contain all vehicles of the owner
 		 * else this->list will contain all vehicles which belong to the selected group */
@@ -3094,7 +3094,7 @@ public:
 		this->DrawWidgets();
 	}
 
-	virtual void DrawWidget(const Rect &r, int widget) const
+	virtual void DrawWidget(const Rect &r, int widget) const override
 	{
 		switch (widget) {
 			case WID_TRSL_ALL_VEHICLES:
@@ -3135,7 +3135,7 @@ public:
 		}
 	}
 
-	virtual void OnClick(Point pt, int widget, int click_count)
+	virtual void OnClick(Point pt, int widget, int click_count) override
 	{
 		switch (widget) {
 			case WID_TRSL_SORT_BY_ORDER: // Flip sorting method ascending/descending
@@ -3258,14 +3258,14 @@ public:
 		}
 	}
 
-	virtual void OnDragDrop(Point pt, int widget)
+	virtual void OnDragDrop(Point pt, int widget) override
 	{
 		if (this->vehicle_sel != INVALID_VEHICLE) OnDragDrop_Vehicle(pt, widget);
 
 		_cursor.vehchain = false;
 	}
 
-	virtual void OnQueryTextFinished(char *str)
+	virtual void OnQueryTextFinished(char *str) override
 	{
 		if (str != nullptr) {
 			if (this->slot_set_max_occupancy) {
@@ -3279,13 +3279,13 @@ public:
 		this->slot_rename = INVALID_TRACE_RESTRICT_SLOT_ID;
 	}
 
-	virtual void OnResize()
+	virtual void OnResize() override
 	{
 		this->slot_sb->SetCapacityFromWidget(this, WID_TRSL_LIST_SLOTS);
 		this->vscroll->SetCapacityFromWidget(this, WID_TRSL_LIST_VEHICLE);
 	}
 
-	virtual void OnDropdownSelect(int widget, int index)
+	virtual void OnDropdownSelect(int widget, int index) override
 	{
 		switch (widget) {
 			case WID_TRSL_SORT_BY_DROPDOWN:
@@ -3309,7 +3309,7 @@ public:
 		}
 	}
 
-	virtual void OnPlaceObjectAbort()
+	virtual void OnPlaceObjectAbort() override
 	{
 		/* abort drag & drop */
 		this->vehicle_sel = INVALID_VEHICLE;
@@ -3318,7 +3318,7 @@ public:
 		this->SetWidgetDirty(WID_TRSL_LIST_VEHICLE);
 	}
 
-	virtual void OnMouseDrag(Point pt, int widget)
+	virtual void OnMouseDrag(Point pt, int widget) override
 	{
 		if (this->vehicle_sel == INVALID_VEHICLE) return;
 
diff --git a/src/vehicle_gui.cpp b/src/vehicle_gui.cpp
index f7309e0772..21a0c3aa60 100644
--- a/src/vehicle_gui.cpp
+++ b/src/vehicle_gui.cpp
@@ -2113,7 +2113,7 @@ public:
 		DoCommandP(0, this->window_number, 0, CMD_CREATE_GROUP_FROM_LIST | CMD_MSG(STR_ERROR_GROUP_CAN_T_CREATE), nullptr, str);
 	}
 
-	virtual void OnPlaceObject(Point pt, TileIndex tile)
+	virtual void OnPlaceObject(Point pt, TileIndex tile) override
 	{
 		/* check depot first */
 		if (IsDepotTile(tile) && GetDepotVehicleType(tile) == this->vli.vtype) {
@@ -2861,7 +2861,7 @@ struct VehicleDetailsWindow : Window {
 		}
 	}
 
-	virtual void OnFocus(Window *previously_focused_window)
+	virtual void OnFocus(Window *previously_focused_window) override
 	{
 		if (HasFocusedVehicleChanged(this->window_number, previously_focused_window)) {
 			if (this->window_number != INVALID_VEHICLE) {
@@ -2872,7 +2872,7 @@ struct VehicleDetailsWindow : Window {
 		}
 	}
 
-	virtual void OnFocusLost(Window *newly_focused_window)
+	virtual void OnFocusLost(Window *newly_focused_window) override
 	{
 		if (HasFocusedVehicleChanged(this->window_number, newly_focused_window)) {
 			if (this->window_number != INVALID_VEHICLE) {
@@ -3177,7 +3177,7 @@ public:
 		DeleteWindowById(WC_VEHICLE_TIMETABLE, this->window_number, false);
 	}
 
-	virtual void OnFocus(Window *previously_focused_window)
+	virtual void OnFocus(Window *previously_focused_window) override
 	{
 		if (HasFocusedVehicleChanged(this->window_number, previously_focused_window)) {
 			if (this->window_number != INVALID_VEHICLE) {
@@ -3188,7 +3188,7 @@ public:
 		}
 	}
 
-	virtual void OnFocusLost(Window *newly_focused_window)
+	virtual void OnFocusLost(Window *newly_focused_window) override
 	{
 		if (HasFocusedVehicleChanged(this->window_number, newly_focused_window)) {
 			if (this->window_number != INVALID_VEHICLE) {
@@ -3496,7 +3496,7 @@ public:
 		}
 	}
 
-	virtual void OnTimeout()
+	virtual void OnTimeout() override
 	{
 		if (!this->depot_select_active) {
 			this->RaiseWidget(WID_VV_GOTO_DEPOT);
@@ -3504,7 +3504,7 @@ public:
 		}
 	}
 
-	virtual void OnPlaceObject(Point pt, TileIndex tile)
+	virtual void OnPlaceObject(Point pt, TileIndex tile) override
 	{
 		const Vehicle *v = Vehicle::Get(this->window_number);
 		if (IsDepotTile(tile) && GetDepotVehicleType(tile) == v->type && IsInfraTileUsageAllowed(v->type, v->owner, tile)) {
@@ -3515,14 +3515,14 @@ public:
 		}
 	}
 
-	virtual void OnPlaceObjectAbort()
+	virtual void OnPlaceObjectAbort() override
 	{
 		this->depot_select_active = false;
 		this->RaiseWidget(WID_VV_GOTO_DEPOT);
 		this->SetWidgetDirty(WID_VV_GOTO_DEPOT);
 	}
 
-	virtual bool OnRightClick(Point pt, int widget)
+	virtual bool OnRightClick(Point pt, int widget) override
 	{
 		if (widget == WID_VV_GOTO_DEPOT && _settings_client.gui.hover_delay_ms == 0) {
 			const Vehicle *v = Vehicle::Get(this->window_number);
@@ -3536,7 +3536,7 @@ public:
 		return false;
 	}
 
-	virtual void OnHover(Point pt, int widget)
+	virtual void OnHover(Point pt, int widget) override
 	{
 		if (widget == WID_VV_GOTO_DEPOT) {
 			const Vehicle *v = Vehicle::Get(this->window_number);
@@ -3582,7 +3582,7 @@ public:
 		}
 	}
 
-	virtual void OnRealtimeTick(uint delta_ms)
+	virtual void OnRealtimeTick(uint delta_ms) override
 	{
 		if (_pause_mode != PM_UNPAUSED) this->OnGameTick();
 	}
diff --git a/src/viewport_gui.cpp b/src/viewport_gui.cpp
index 2b33f8a7ef..d66424aa6b 100644
--- a/src/viewport_gui.cpp
+++ b/src/viewport_gui.cpp
@@ -153,7 +153,7 @@ public:
 		}
 	}
 
-	virtual void OnMouseOver(Point pt, int widget)
+	virtual void OnMouseOver(Point pt, int widget) override
 	{
 		if (pt.x != -1 && (_mouse_hovering || _settings_client.gui.hover_delay_ms == 0)) {
 			/* Show tooltip with last month production or town name */