Method CheckReturn

source/common/scripting/backend/codegen.cpp:130–186

}

void FCompileContext::CheckReturn(PPrototype *proto, FScriptPosition &pos)
{
	assert(proto != nullptr);
	bool fail = false;

	if (ReturnProto == nullptr)
	{
		ReturnProto = proto;
		return;
	}

	// A prototype that defines fewer return types can be compatible with
	// one that defines more if the shorter one matches the initial types
	// for the longer one.
	bool swapped = false;

	if (ReturnProto->ReturnTypes.Size() < proto->ReturnTypes.Size())
	{ // Make proto the shorter one to avoid code duplication below.
		std::swap(proto, ReturnProto);
		swapped = true;
	}
	// If one prototype returns nothing, they both must.
	if (proto->ReturnTypes.Size() == 0)
	{
		if (ReturnProto->ReturnTypes.Size() != 0)
		{
			fail = true;
		}
	}
	else
	{
		for (unsigned i = 0; i < proto->ReturnTypes.Size(); i++)
		{
			PType* expected = ReturnProto->ReturnTypes[i];
			PType* actual = proto->ReturnTypes[i];
			if (swapped) std::swap(expected, actual);
			// this must pass for older ZScripts.
			if (Version < MakeVersion(4, 12, 0))
			{
				if (expected == TypeTranslationID) expected = TypeSInt32;
				if (actual == TypeTranslationID) actual = TypeSInt32;
			}

			if (expected != actual && !AreCompatiblePointerTypes(expected, actual))
			{ // Incompatible
				Printf("Return type %s mismatch with %s\n", expected->DescriptiveName(), actual->DescriptiveName());
				fail = true;
				break;
			}
		}
	}

	if (fail)
	{
		pos.Message(MSG_ERROR, "Return type mismatch");
	}
}