Is there anything in the language specifications (mainly C++ in this context, but is this an area where C and C++ are going to diverge, or is C likely to follow suit?) that prohibits spurious writes to a location?
Surely the deal is that spurious writes are allowed unless the location is volatile. What other interpretation is possible?
That's what I thought. So, unless the compiler (or language spec) is going to become thread-aware, any data to be shared across threads needs to be declared volatile, even if some other mechanism (like a mutex) is in use to do some synchronization. Which means performance would be poor for any such data.
Which takes me back to: I think the compiler needs to be thread-aware. "Enhancing" the meaning of volatile, with the attendant performance issues, still doesn't seem adequate to allow for multithreaded programming, unless it's used *everywhere*, and performance shoots through the floor....
