> Did this reach you guys? I got a weird undeliverable message. Nope, I hadn't seen it. > More clues: in CPS, the Failure exception carries string, while in SSA it > carries (string, unit ref). So, something in useless (that's the only > pass that might figure out that the unit ref is the same everywhere?). Constant propagation moves refs to toplevel if it can prove they are only allocated once.