diff --git a/src/newgrf_object.h b/src/newgrf_object.h
--- a/src/newgrf_object.h
+++ b/src/newgrf_object.h
@@ -116,8 +116,8 @@ struct ObjectScopeResolver : public Scop
 	{
 	}
 
-	/* virtual */ uint32 GetRandomBits() const;
-	/* virtual */ uint32 GetVariable(byte variable, uint32 parameter, bool *available) const;
+	uint32 GetRandomBits() const override;
+	uint32 GetVariable(byte variable, uint32 parameter, bool *available) const override;
 };
 
 /** A resolver object to be used with feature 0F spritegroups. */
@@ -129,7 +129,7 @@ struct ObjectResolverObject : public Res
 			CallbackID callback = CBID_NO_CALLBACK, uint32 param1 = 0, uint32 param2 = 0);
 	~ObjectResolverObject();
 
-	/* virtual */ ScopeResolver *GetScope(VarSpriteGroupScope scope = VSG_SCOPE_SELF, byte relative = 0)
+	ScopeResolver *GetScope(VarSpriteGroupScope scope = VSG_SCOPE_SELF, byte relative = 0) override
 	{
 		switch (scope) {
 			case VSG_SCOPE_SELF: