Undefined behaviour with const_cast

Question

I was hoping that someone could clarify exactly what is meant by undefined behaviour in C++. Given the following class definition:

class Foo
{
public:
             


        

Answer 1

Static and const data are often stored in another part of you program than local variables. For const variables, these areas are often in read-only mode to enforce the constness of the variables. Attempting to write in a read-only memory results in an "undefined behavior" because the reaction depends on your operating system. "Undefined beheavior" means that the language doesn't specify how this case is to be handled.

If you want a more detailed explanation about memory, I suggest you read this. It's an explanation based on UNIX but similar mecanism are used on all OS.