Re: Am I or Alexandrescu wrong about singletons?
"Herb Sutter" <firstname.lastname@example.org> wrote in message
On Wed, 17 Mar 2010 21:16:23 CST, "Leigh Johnston" <email@example.com>
You are incorrect to claim that volatile as defined by the current C++
standard has no use in multi-threaded programming. Whilst volatile does
guarantee atomicity nor memory ordering across multiple threads the fact
that it prevents the compiler from caching vales in registers is useful
Yes, volatile does that. Unfortunately, that is necessary but not
sufficient for inter-thread communication to work correctly. Volatile
is for hardware access; std::atomic<T> is for multithreaded code
synchronized without mutexes.
That was my point, volatile whilst not a solution in itself is a "part" of a
solution for multi-threaded programming when using a C++ (current standard)
finished = false;
/* do work */
/* do work */
finished = true;
If finished is not volatile and compiler optimizations are enabled thread A
may loop forever.
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