Volatile is a keyword that allows you to turn off certain optimizations. Unfortunately, it’s also used incorrectly many times as a way to synchronize threads.

If you have code that checks a variable for a specific value and you know that the value can be changed through some means that your compiler is not aware of, then declaring the variable to be volatile is perfect. That’s what it’s intended for.

Where some developers run into problem though is when trying to use this technique to synchronize the activities between threads. Maybe by creating a variable called done that will be set to true once other variable have been set properly. There are many problems with this that this episode describes.

My advice is that while volatile can be useful sometimes, don’t try to use it for any type of thread synchronization. There’s just too many ways it can go wrong. Take the time to use proper thread locking and synchronization methods.


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