The commented out regions mentioning this worked as is.
I don't know if these were left commented out because they don't work on
some platforms, but they work on OS X. Were they left commented out because
they had been forgotten?
Howard, it looks like you’re the one that added the commented out behavior, and your commit said that you “could not yet do that”. Any update?
Howard has moved on to other projects, and I don’t think that email works anymore. Marshall is the current libc++ maintainer, maybe he knows?