I am aware of the general guideline “Do not use const inside classes,” but I have encountered situations where I am unsure about the proper declaration of variables. For example, consider the following code:

#include <cstdio>
#include <cstdint>

class Driver {
public:
    /** Collection of I2C addresses */
    enum class I2CAddress : uint8_t {
        Address_0 = 0x0,
        Address_1 = 0x1,
    };

    /** Constructor */
    explicit Driver(I2CAddress i2cAddress) : Address(i2cAddress) {};
    
private:
    /** Selected I2C address */
    const I2CAddress Address;
};

int main() {
    Driver driver {Driver::I2CAddress::Address_0};

    return 0;
}

In this example, it makes sense for Address to be constant, but I am wondering about the implications of marking it as const:

1. Compiler Optimizations: Does marking a private member variable as const provide any compiler optimizations, or is it redundant since it cannot be externally modified?

2. Error Prevention: While marking it const can prevent accidental assignments (e.g., using = instead of == in a comparison)?

3. Optimal Implementation: For constants like this, is the example above the optimal implementation, or would it be better to have a const-free class and declare the object itself as const when needed? For instance:

   class Driver {
   public:
       enum class I2CAddress : uint8_t {
           Address_0 = 0x0,
           Address_1 = 0x1,
       };
   
       explicit Driver(I2CAddress i2cAddress) : Address(i2cAddress) {};
   
       I2CAddress getAddress() const { return Address; }
   
   private:
       I2CAddress Address;
   };
   
   int main() {
       const Driver driver {Driver::I2CAddress::Address_0};
   
       return 0;
   }
   

Which approach is more appropriate in terms of performance, maintainability, and best practices in C++?