On 06/03/10 15:54, John Regehr wrote: >> I'm not sure this follows. It's stated explicitly that "The >> expression is evaluated and its value is discarded." How can you >> evaluate the expression without reading the volatle? > > I'm certainly not an expert on this material but I wouldn't think you'd > normally read a variable in order to evaluate it as an lvalue. My guess > is that evaluating the expression means computing the address for > something like "*(p+1)".
Yes, I see your point. >> Besides, all that changing this would do is break programs. > > Well they're broken anyway since widely-used C++ compilers are choosing > to not read the variable under these circumstances. The obvious > solution is "don't do that" but there's plenty of code doing this out > there, and plenty of developers who need re-educating. I guess. Given that the semantics of volatile are implementation- defined anyway, I can't see that this is a conformance issue. Andrew.
