From: Michael Glassford [mailto:glassfordm@hotmail.com] One potential problem that I am aware of is that it is possible for the m_generation counter (see barrier.cpp) to overflow on systems that detect overflow of integer addition instead of wrapping (I assume there are such systems though I've never used one). Is it worthwhile checking for this and forcing wrapping in code?

Checking for overflow isn't needed in this case, since the underlying type is unsigned (and unsigned integer arithmetic does not overflow [per §3.9.1.4]). Bjorn