[Bug libstdc++/61617] add boost::coroutine

[piotr5 at netscape dot net]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61617

--- Comment #4 from piotr5 at netscape dot net ---
thanks anyway. so what is the standards comitee's "direction" for making
arbitrary-width-tree iterators more comprehensible, if not an iteration over
multiple children for each level's node? does boost::coroutine contradict
anything among gcc-commitee's plans? guess I'll ask that directly elsewhere and
post my findings here, if you don't reply.