volatile vs. mutable in C++

Question

I have a question about the difference between volatile and mutable. I noticed that both of the two means that it could be changed. What else? Are they the same thing? What\

Answer 1

They are definitely NOT the same thing. Mutable interacts with const. If you have a const pointer, you normally could not change members. Mutable provides an exception to that rule.

Volatile, on the other hand, is totally unrelated to changes made by the program. It means that the memory could change for reasons beyond the control of the compiler, therefore the compiler has to read or write the memory address every time and can't cache the content in a register.