Re: MSDN volatile sample


George schrieb:

In the MSDN volatile sample,

http://msdn2.microsoft.com/en-us/library/12a04hfd(VS.80).aspx

I do not understand what is the purpose of the sample. I have tried to remove the keyword volatile, and the result is the same. :-)

THe result may be the same with your compiler version and optimizer setting, but is is not guaranteed to work without volatile. volatile tells the compiler not to optimize the use of the variable because it could be modified at any time by something the compiler has no control over.

Code with a "forgotten volatile" at the right place can work for years but fail unexpected after minor unrelated code changes.

Norbert
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