IntervalMap warning

Anyone seeing this, too?

include/llvm/ADT/IntervalMap.h:562:58:
warning: array subscript is above array bounds [-Warray-bounds]
const KeyT &stop(unsigned i) const { return this->first[i].second; }

It seems the [i] is out of bounds, but the code is a bit dense and I
couldn't find anything obviously wrong with it. It only shows when
you're building the unit tests and the test calls directly for
treeAvanceTo().

cheers,
--renato

Yeah, I saw that and looked at it for 5 mins and couldn't see it, but
was busy and went off to something else.

-eric