Re: strange grammar about volatile and operator overload

From:
"Igor Tandetnik" <itandetnik@mvps.org>
Newsgroups:
microsoft.public.vc.language
Date:
Tue, 29 Jan 2008 21:21:50 -0500
Message-ID:
<up3ngbuYIHA.5164@TK2MSFTNGP03.phx.gbl>
"George" <George@discussions.microsoft.com> wrote in message
news:BB2B4E82-3B35-482F-A41B-5E7C60DBDC00@microsoft.com

But I am not sure whether volatile is consistent to the reference
binded object. For example, the operator conversion function returns
reference to some global object and it is marked as volatile now, but
actually in the definition/declaration of the global object, it is
not marked as volatile.


That's perfectly OK. Just as you can have a reference-to-const bound to
an object that wasn't declared const:

int x;
const int& cr = x; // OK
volatile int& vr = x; // also OK

When x is accessed directly, it's not treated as volatile or const. When
x is accessed via vr reference, it's treated as volatile (meaning
certain compiler optimizations are suppressed). When x is accessed via
cr reference, it's treated as const (meaning you can read the value but
can't change it).

I am not sure about whether I have made
myself understood about the volatile consistent issue.


No, not really.

Any comments? Is it an issue


Is what an issue?

or just make the global variable in my
sample more restrictive (volatile is more restrictive than
non-volatile)?


Yes, volatile is more restrictive.
--
With best wishes,
    Igor Tandetnik

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