Remove UNUSED

The `UNUSED` macro is used to mark a variable as unused but with a name.
Those usages are replaced with comments so that `UNUSED` can be removed.

https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#Rf-unused

source/gui/GUIStringConversions.cpp

@@ -235,13 +235,13 @@ bool CGUI::ParseString<CGUISpriteInstance>(const CGUI*, const CStrW& Value, CGUI
 }
 
 template <>
-bool CGUI::ParseString<CGUISeries>(const CGUI*, const CStrW& UNUSED(Value), CGUISeries& UNUSED(Output))
+bool CGUI::ParseString<CGUISeries>(const CGUI*, const CStrW& /*Value*/, CGUISeries& /*Output*/)
 {
 	return false;
 }
 
 template <>
-bool CGUI::ParseString<CGUIList>(const CGUI*, const CStrW& UNUSED(Value), CGUIList& UNUSED(Output))
+bool CGUI::ParseString<CGUIList>(const CGUI*, const CStrW& /*Value*/, CGUIList& /*Output*/)
 {
 	return false;
 }

source/gui/IGUIScrollBar.h

@@ -1,4 +1,4 @@
-/* Copyright (C) 2024 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -191,7 +191,7 @@ public:
 	 * @param mouse current mouse position
 	 * @return True if mouse positions are hovering the button
 	 */
-	virtual bool HoveringButtonMinus(const CVector2D& UNUSED(mouse)) { return false; }
+	virtual bool HoveringButtonMinus(const CVector2D& /*mouse*/) { return false; }
 
 	/**
 	 * Hovering the scroll plus button
@@ -199,7 +199,7 @@ public:
 	 * @param mouse current mouse position
 	 * @return True if mouse positions are hovering the button
 	 */
-	virtual bool HoveringButtonPlus(const CVector2D& UNUSED(mouse)) { return false; }
+	virtual bool HoveringButtonPlus(const CVector2D& /*mouse*/) { return false; }
 
 	/**
 	 * Get scroll-position

source/gui/ObjectBases/IGUIObject.h

@@ -373,7 +373,7 @@ protected:
 	 * Notice 'false' is default, because an object not using this function, should not
 	 * have any additional children (and this function should never be called).
 	 */
-	virtual bool HandleAdditionalChildren(const XMBData& UNUSED(file), const XMBElement& UNUSED(child))
+	virtual bool HandleAdditionalChildren(const XMBData& /*file*/, const XMBElement& /*child*/)
 	{
 		return false;
 	}

source/gui/ObjectTypes/CMiniMap.cpp

@@ -244,7 +244,7 @@ CVector2D CMiniMap::WorldSpaceToMiniMapSpace(const CVector3D& worldPosition) con
 		m_CachedActualSize.bottom - (0.5f + rotatedY) * m_CachedActualSize.GetHeight());
 }
 
-bool CMiniMap::FireWorldClickEvent(int button, int UNUSED(clicks))
+bool CMiniMap::FireWorldClickEvent(int button, int /*clicks*/)
 {
 	ScriptRequest rq(g_GUI->GetActiveGUI()->GetScriptInterface());
 

source/gui/Scripting/JSInterface_GUIProxy.h

@@ -169,48 +169,48 @@ protected:
 	// We provide defaults that do nothing (some raise JS exceptions).
 
 	// The JS code will see undefined when querying a property descriptor.
-	virtual bool getOwnPropertyDescriptor(JSContext*, JS::HandleObject UNUSED(proxy), JS::HandleId,
+	virtual bool getOwnPropertyDescriptor(JSContext*, JS::HandleObject /*proxy*/, JS::HandleId,
 		JS::MutableHandle<mozilla::Maybe<JS::PropertyDescriptor>>) const override
 	{
 		return true;
 	}
 	// Throw an exception is JS code attempts defining a property.
-	virtual bool defineProperty(JSContext*, JS::HandleObject UNUSED(proxy), JS::HandleId,
-		JS::Handle<JS::PropertyDescriptor>, JS::ObjectOpResult& UNUSED(result)) const override
+	virtual bool defineProperty(JSContext*, JS::HandleObject /*proxy*/, JS::HandleId,
+		JS::Handle<JS::PropertyDescriptor>, JS::ObjectOpResult& /*result*/) const override
 	{
 		return false;
 	}
 	// No accessible properties.
-	virtual bool ownPropertyKeys(JSContext*, JS::HandleObject UNUSED(proxy),
-		JS::MutableHandleIdVector UNUSED(props)) const override
+	virtual bool ownPropertyKeys(JSContext*, JS::HandleObject /*proxy*/,
+		JS::MutableHandleIdVector) const override
 	{
 		return true;
 	}
 	// Nothing to enumerate.
-	virtual bool enumerate(JSContext*, JS::HandleObject UNUSED(proxy),
-		JS::MutableHandleIdVector UNUSED(props)) const override
+	virtual bool enumerate(JSContext*, JS::HandleObject /*proxy*/,
+		JS::MutableHandleIdVector /*props*/) const override
 	{
 		return true;
 	}
 	// Throw an exception is JS attempts to query the prototype.
-	virtual bool getPrototypeIfOrdinary(JSContext*, JS::HandleObject UNUSED(proxy),
-		bool* UNUSED(isOrdinary), JS::MutableHandleObject UNUSED(protop)) const override
+	virtual bool getPrototypeIfOrdinary(JSContext*, JS::HandleObject /*proxy*/, bool* /*isOrdinary*/,
+		JS::MutableHandleObject /*protop*/) const override
 	{
 		return false;
 	}
 	// Throw an exception - no prototype to set.
-	virtual bool setImmutablePrototype(JSContext*, JS::HandleObject UNUSED(proxy),
-		bool* UNUSED(succeeded)) const override
+	virtual bool setImmutablePrototype(JSContext*, JS::HandleObject /*proxy*/,
+		bool* /*succeeded*/) const override
 	{
 		return false;
 	}
 	// We are not extensible.
-	virtual bool preventExtensions(JSContext*, JS::HandleObject UNUSED(proxy),
-		JS::ObjectOpResult&) const override
+	virtual bool preventExtensions(JSContext*, JS::HandleObject /*proxy*/,
+		JS::ObjectOpResult& /*result*/) const override
 	{
 		return true;
 	}
-	virtual bool isExtensible(JSContext*, JS::HandleObject UNUSED(proxy), bool* extensible) const override
+	virtual bool isExtensible(JSContext*, JS::HandleObject /*proxy*/, bool* extensible) const override
 	{
 		*extensible = false;
 		return true;

source/gui/Scripting/JSInterface_GUIProxy_impl.h

@@ -167,7 +167,8 @@ std::unique_ptr<IGUIProxyObject> JSI_GUIProxy<T>::CreateJSObject(const ScriptReq
 }
 
 template <typename T>
-bool JSI_GUIProxy<T>::get(JSContext* cx, JS::HandleObject proxy, JS::HandleValue UNUSED(receiver), JS::HandleId id, JS::MutableHandleValue vp) const
+bool JSI_GUIProxy<T>::get(JSContext* cx, JS::HandleObject proxy, JS::HandleValue /*receiver*/,
+	JS::HandleId id, JS::MutableHandleValue vp) const
 {
 	ScriptRequest rq(cx);
 
@@ -237,7 +238,7 @@ bool JSI_GUIProxy<T>::get(JSContext* cx, JS::HandleObject proxy, JS::HandleValue
 
 template <typename T>
 bool JSI_GUIProxy<T>::set(JSContext* cx, JS::HandleObject proxy, JS::HandleId id, JS::HandleValue vp,
-							JS::HandleValue UNUSED(receiver), JS::ObjectOpResult& result) const
+	JS::HandleValue /*receiver*/, JS::ObjectOpResult& result) const
 {
 	T* e = IGUIProxyObject::FromPrivateSlot<T>(proxy.get());
 	if (!e)