Re: mutex question

"Tom Widmer" <tom_usenet@xxxxxxxxxxx> wrote in message
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Slava M. Usov wrote:
"Tom Widmer [VC++ MVP]" <tom_usenet@xxxxxxxxxxx> wrote in message
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Slava M. Usov wrote:


[...]


Reads and writes did happen; your "corrupt" involves an ad hoc
assumption -- the atomicity of reads and writes.

It's neither ad hoc nor an assumption, but a requirement of "sufficient".


Atomicity is a requirement for reading or writing?

Yes. What's your definition of "sufficient" in the context of this thread?

Something is sufficient for externally observable reads and writes when
externally observable reads and writes happen. Atomicity is completely and
entirely irrelevant here.

[...]

That program didn't do anything useful.

Ignoratio elenchi.

[...]

In any case, I believe it can be written more efficiently (without getting
rid of the spin lock) as:

Introducing write and read barriers hardly makes things more efficient.
Introducing MSFT-specific language extensions hardly makes things more
portable.

S


.

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