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Re: -fno-tree-cselim not working?
skaller <firstname.lastname@example.org> writes:
> On Fri, 2007-10-26 at 08:27 -0700, Ian Lance Taylor wrote:
> > skaller <email@example.com> writes:
> > > I understand that's the common meaning .. but the semantics
> > > aren't specified for ISO C/C++.
> > Sure they are. In the C99 standard look at the definition of sequence
> > points (184.108.40.206) and the definition of volatile (6.7.3).
> 6.7.3 volatile bullet is non-normative. As pointed
> out in previous post: volatile accesses are observable.
> What 6.7.3 says is not a definition, but something which can
> be deduced from their status as observables.
> The key point which makes this waffle is the bit that says
> 'what constitutes an access is implementation defined'.
OK, fair enough.
Of course, the gcc implementation does define it in the documentation.