Bump crossbeam.

ethcore/Cargo.toml

@@ -12,7 +12,7 @@ blooms-db = { path = "../util/blooms-db" }
 bn = { git = "https://github.com/paritytech/bn", default-features = false }
 byteorder = "1.0"
 common-types = { path = "types" }
-crossbeam = "0.3"
+crossbeam = "0.4"
 ethash = { path = "../ethash" }
 ethcore-bloom-journal = { path = "../util/bloom" }
 parity-bytes = "0.1"

ethcore/src/executive.rs

@@ -979,7 +979,7 @@ impl<'a, B: 'a + StateBackend> Executive<'a, B> {
 				scope.builder().stack_size(::std::cmp::max(self.schedule.max_depth.saturating_sub(depth_threshold) * STACK_SIZE_PER_DEPTH, local_stack_size)).spawn(move || {
 					self.call_with_stack_depth(params, substate, stack_depth, tracer, vm_tracer)
 				}).expect("Sub-thread creation cannot fail; the host might run out of resources; qed")
-			}).join()
+			}).join().expect("Sub-thread never panics; qed")
 		}
 	}
 
@@ -1063,7 +1063,7 @@ impl<'a, B: 'a + StateBackend> Executive<'a, B> {
 				scope.builder().stack_size(::std::cmp::max(self.schedule.max_depth.saturating_sub(depth_threshold) * STACK_SIZE_PER_DEPTH, local_stack_size)).spawn(move || {
 					self.create_with_stack_depth(params, substate, stack_depth, tracer, vm_tracer)
 				}).expect("Sub-thread creation cannot fail; the host might run out of resources; qed")
-			}).join()
+			}).join().expect("Sub-thread never panics; qed")
 		}
 	}
 

ethcore/src/snapshot/mod.rs

@@ -192,11 +192,11 @@ pub fn take_snapshot<W: SnapshotWriter + Send>(
 			state_guards.push(state_guard);
 		}
 
-		let block_hashes = block_guard.join()?;
+		let block_hashes = block_guard.join().expect("Sub-thread never panics; qed")?;
 		let mut state_hashes = Vec::new();
 
 		for guard in state_guards {
-			let part_state_hashes = guard.join()?;
+			let part_state_hashes = guard.join().expect("Sub-thread never panics; qed")?;
 			state_hashes.extend(part_state_hashes);
 		}