> It sounds like you don’t get what the articles point is.

Yes I do. It’s simply wrong. What it says about type annotation is correct, but has zero to do with threading because volatile has zero meaning for accesses from different threads. It then uses volatile to (incorrectly) build threading code. You seem to think volatile has some usefulness for threaded code; it does not. You think volatile adds benefit to your code above; it does not. The type annotation does not give you the ability to have compilers check race conditions for you - it works on some and will fail on others.

Add volatile to your bar function. Oops, got race conditions. Volatile is not protecting your code; properly using mutexes is. Requiring programmers to intersperse volatile as some type annotation makes code more error prone, not less. One still has to correctly do the hard parts, but now with added confusion, verbosity, and treading on undefined behavior.

I think you believe his claim “We can make the compiler check race conditions for us.” because you’re relying on the same claim compilers will check volatile in the manner your code above does. That’s undefined behavior, open to compiler whims. Good luck with that. There’s a reason C++ added the more nuanced ordering specifications - to handle the myriad ways some architectures worked (and to mirror discoveries made in academic literature on the topic that happened after this article was written).

This article is even mentioned in the proposal to remove volatile from C++ altogether http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p115.... I’ve known about this for some time, and hacking in type annotations like this adds no value; it simply makes a mess.

More errors from the article, which is why people should stop citing it:

First sentence:

“The volatile keyword was devised to prevent compiler optimizations that might render code incorrect in the presence of certain asynchronous events.”

This is simply wrong. The article goes on to try to make multithreaded code correct using volatile.

More quotes from the article that are simply wrong: “Although both C and C++ Standards are conspicuously silent when it comes to threads, they do make a little concession to multithreading, in the form of the volatile keyword.” Wrong; see Sutter quote below. “Just like its better-known counterpart const, volatile is a type modifier. It's intended to be used in conjunction with variables that are accessed and modified in different threads.” Wrong. See Sutter quote, and ISO standards. Volatile was never intended for this, so was never safe for doing this. “In spite of its simplicity, LockingPtr is a very useful aid in writing correct multithreaded code. You should define objects that are shared between threads as volatile” wrong on so many levels. The referenced code will break on many, many architectures. There is simply no defense to this.

The article has dozens more incorrect statements and code samples trying to make threadsafe code via volatile.

I’ve written articles on this. I’ve taught professional programmers this. I’ve designed high performance C++ multithreaded code for quite a while. It’s simply wrong, full stop.

Here’s a correct destruction of the Dobbs article by someone who gets it [1]. They, like you, were once misled by this article.

The money quote, from Herb Sutter “Please remember this: Standard ISO C/C++ volatile is useless for multithreaded programming. No argument otherwise holds water; at best the code may appear to work on some compilers/platforms”

I suspect you’ll still stick to the claim this article has value, given your insistence so far against so many people giving you correct advice. Good luck.

[1] https://sites.google.com/site/kjellhedstrom2/stay-away-from-...