[SOLVED] segmentation fault when trying to cast IGUIElement to

[fargoth]

I'm trying to retrieve the value selected on a menu.

The following line gives seg fault on

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dynamic_cast<std::remove_pointer_t<T> *>(guiElement);

From here:

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                std::remove_pointer_t<T> * getGuiElement(int in_id)
		{
			//check that T is a valid type to try to upcast during compile time.
			static_assert(std::is_base_of<irr::gui::IGUIElement, std::remove_pointer_t<T>>::value, 
				"T must inherit irr::gui::IGUIElement");
			if (!_guiEnv)
			{
				//LOG(ERROR) << "gui environment is null";
				throw std::runtime_error("menu was not set correctly!");
			}
			if (!_guiEnv->getRootGUIElement())
			{
				throw std::runtime_error("no gui root element");
			}
			auto guiElement = _guiEnv->getRootGUIElement()->getElementFromId(in_id);
			if (!guiElement)
			{
				throw std::runtime_error("Could not find gui element");
			}
			auto requestedElement = dynamic_cast<std::remove_pointer_t<T> *>(guiElement);
			if (!requestedElement)
			{
				throw std::runtime_error("Failed dynamic casting of GUI element");
			}
			return requestedElement;
		}

It gets called like this:

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getGuiElement<irr::gui::IGUISpinBox>(MenuElement::MazeNumOfAI)->getValue();

It was created like so:

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		auto spinBox = _guiEnv->addSpinBox(L"Number of AI players", irr::core::recti(elementPosition, elementSize),true,nullptr,MenuElement::MazeNumOfAI);
		spinBox->setDecimalPlaces(0);
		spinBox->setRange(0.0f, 10.0f);
		spinBox->setValue(3.0f);
		_gameSettingsElements.push_back(spinBox);

Any idea what may be the problem?

[fargoth]

Ah, I've found it Needed to disable RTTI and use static_cast instead of dynamic_cast...

[Noiecity]

great

[CuteAlien]

You don't have to disable RTTI in your own project. But Irrlicht indeed compiles without RTTI, so dynamic_cast on Irrlicht pointers will always fail.