parity compiling fine

sync/src/lib.rs

@@ -17,7 +17,7 @@
 #![warn(missing_docs)]
 #![cfg_attr(feature="dev", feature(plugin))]
 #![cfg_attr(feature="dev", plugin(clippy))]
-#![feature(augmented_assignments)]
+//#![feature(augmented_assignments)]
 // Keeps consistency (all lines with `.clone()`) and helpful when changing ref to non-ref.
 #![allow(clone_on_copy)]
 
@@ -59,7 +59,7 @@ use std::ops::*;
 use std::sync::*;
 use ethcore::client::Client;
 use util::network::{NetworkProtocolHandler, NetworkService, NetworkContext, PeerId};
-use util::io::TimerToken;
+use util::TimerToken;
 use chain::ChainSync;
 use ethcore::service::SyncMessage;
 use io::NetSyncIo;

sync/src/tests/helpers.rs

@@ -213,7 +213,10 @@ impl BlockChainClient for TestBlockChainClient {
 		}
 		let len = self.numbers.read().unwrap().len();
 		if number == len {
-			*self.difficulty.write().unwrap().deref_mut() += header.difficulty;
+			{
+				let mut difficulty = self.difficulty.write().unwrap();
+				*difficulty.deref_mut() = *difficulty.deref() + header.difficulty;
+			}
 			mem::replace(self.last_hash.write().unwrap().deref_mut(), h.clone());
 			self.blocks.write().unwrap().insert(h.clone(), b);
 			self.numbers.write().unwrap().insert(number, h.clone());