Subj : Re: STL Containers w/ Virtually Zero-Overhead Lock-Free Reads...
To   : comp.programming.threads
From : Alexander Terekhov
Date : Tue Sep 20 2005 04:51 pm

< .moderated stripped >

kanze wrote:
> 
> Chris Thomasson wrote:
> 
> > Should it be done?
> 
> I'm not sure exactly what you are asking for.  Currently, the
> SGI implementation doesn't require external synchronization if
> all accesses are non-modifying.  Globally, I don't think that
> they had to do anything special to achieve this.  (It does mean
> that std::string cannot be COW.)
  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

That's not true. James Kanze has a rather strange notion of 
"non-modifying" accesses in C++. Under his theory, if a non-const 
member function has a const counterpart, than both must be "non-
modifying"... never mind that the standard explicitly "warns"
(albeit the claus is a bit defective) about invalidations caused 
by non-const begin() et. al in 21.3/5.

regards,
alexander.

.