New version of crossbeam-deque (#468)

ci/tsan

@@ -12,15 +12,14 @@ race:std*mpsc_queue
 # Probably more fences in std.
 race:__call_tls_dtors
 
-# The crossbeam deque uses fences.
-race:crossbeam_deque
+# The epoch-based GC uses fences.
+race:crossbeam_epoch
 
-# This is excluded as this race shows up due to using the stealing features of
-# the deque. Unfortunately, the implementation uses a fence, which makes tsan
-# unhappy.
-#
-# TODO: It would be nice to not have to filter this out.
-race:try_steal_task
+# Push and steal operations in crossbeam-deque may cause data races, but such
+# data races are safe. If a data race happens, the value read by `steal` is
+# forgotten and the steal operation is then retried.
+race:crossbeam_deque*push
+race:crossbeam_deque*steal
 
 # This filters out expected data race in the treiber stack implementations.
 # Treiber stacks are inherently racy. The pop operation will attempt to access