(* Actual races *)
let ww-nonrace = ww-vis & ((Marked * W) | rw-xbstar) & ((W * Marked) | wr-vis)
let ww-race = (pre-race & co) \ ww-nonrace
-let wr-race = (pre-race & (co? ; rf)) \ wr-vis
+let wr-race = (pre-race & (co? ; rf)) \ wr-vis \ rw-xbstar^-1
let rw-race = (pre-race & fr) \ rw-xbstar
flag ~empty (ww-race | wr-race | rw-race) as data-race