EEPROM validity using checksums when using Multiple Inheritance

Firmware
1

I have been following the example posted here

I am using Multiple Inheritance on an object i call Save. The following is an example of how it is structured

class Save {
	int a;
	int b;

	//some methods
};

class SaveA :public virtual Save {
	int c;
	int d;

	//some methods
};

class SaveB :public virtual Save {
	enum class X:int{TYPE1,TYPE2};
	X settings1;
	X settings2;

	//some methods
};

class SaveAB :public SaveA, public SaveB {
	int y;
	int z;

	//some methods
};

I have verified that EEPROM.put and EEPROM.get save the data members just fine but i am a bit unsure about how to make sure the data is valid upon reset.

In the topic i linked above the checksums were done inside structs and some padding was used at the end of the data members. What would be a recommended way of checking for data validity in the above example?