I recently had an interview with a software company who asked me the following question:
Can you describe to me what adding volatile in front of variables does? Can you explain to me why it's important?
Most of my programming knowledge comes from C, yet the job position is for C# (I thought I might add this bit of info if necessary for the question specifically)
I answered by saying it just lets the compiler know that the variable can be used across processes or threads, and that it should not use optimization on that variable; as optimizing it can deteriorate behavior. In a nutshell, it's a warning to the compiler.
According to the interviewer, however, it's the other way around, and the volatile keyword warns the OS, not the compiler.
I was a bit befuddled by this, so I did some research and actually found conflicting answers! Some sources say it's for the compiler, and others for the OS.
Which is it? Does it differ by language?
