Usefulness of volatile in concurrent programming since C++11

Question

I've read this and this answer. I've also searched the book C++ Concurrency in Action and found no discussion about volatile nor any example using it. Looks like it's not designed for concurrency at all. So for concurrent programming, is it sufficient to just use atomic, mutex, etc., and forget about volatile? Any cases where volatile may be needed for concurrency issues?

Answer 1

No, in C++ the volatile keyword tells the compiler that must not optimize the variable in any way shape or form. This can be useful when dealing with memory that can be changed from outside of your own code e.g a hardware register on a custom board.
For more in depth guide about volatile you should read Volatile vs. volatile By Herb Sutter