volatile [was: GCC warnings for unused global variables]

[Alexandre Oliva]

On May  4, 2003, Fergus Henderson <fjh@cs.mu.OZ.AU> wrote:

>> They can be
>> created with the initialized value, if that can be calculated at
>> compile time (e.g., if there is no constructor).

> That is true for non-volatile variables, but only because the compiler
> can apply the as-if rule.  As discussed earlier in this thread, the
> as-if rule does not apply to volatile variables -- the standard prohibits
> implementations from optimizing away accesses to volatile variables.

Except that the object only becomes volatile after it is initialized.
Otherwise, there'd be no constructor to initialize it, since
cv-qualifiers don't make it to the type of `this' in cdtors.

-- 
Alexandre Oliva   Enjoy Guarana', see http://www.ic.unicamp.br/~oliva/
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