diff --git a/beacon_node/client/src/client_config.rs b/beacon_node/client/src/client_config.rs
index 243848e9f..d8d3f2c4a 100644
--- a/beacon_node/client/src/client_config.rs
+++ b/beacon_node/client/src/client_config.rs
@@ -98,7 +98,7 @@ impl ClientConfig {
 
         // Custom bootnodes
         if let Some(boot_addresses_str) = args.value_of("boot-nodes") {
-            let mut boot_addresses_split = boot_addresses_str.split(",");
+            let boot_addresses_split = boot_addresses_str.split(",");
             for boot_address in boot_addresses_split {
                 if let Ok(boot_address) = boot_address.parse::<Multiaddr>() {
                     config.net_conf.boot_nodes.append(&mut vec![boot_address]);
diff --git a/eth2/fork_choice/src/bitwise_lmd_ghost.rs b/eth2/fork_choice/src/bitwise_lmd_ghost.rs
index a26a94b8a..129dca985 100644
--- a/eth2/fork_choice/src/bitwise_lmd_ghost.rs
+++ b/eth2/fork_choice/src/bitwise_lmd_ghost.rs
@@ -124,8 +124,9 @@ impl<T: Store, E: EthSpec> BitwiseLMDGhost<T, E> {
                 [log2_int((block_height - target_height - 1u64).as_u64()) as usize]
                 .get(&block_hash)
                 //TODO: Panic if we can't lookup and fork choice fails
-                .expect("All blocks should be added to the ancestor log lookup table");
-            self.get_ancestor(*ancestor_lookup, target_height, &spec)
+                .expect("All blocks should be added to the ancestor log lookup table")
+                .clone();
+            self.get_ancestor(ancestor_lookup, target_height, &spec)
         } {
             // add the result to the cache
             self.cache.insert(cache_key, ancestor);
@@ -151,7 +152,7 @@ impl<T: Store, E: EthSpec> BitwiseLMDGhost<T, E> {
         // these have already been weighted by balance
         for (hash, votes) in latest_votes.iter() {
             if let Some(ancestor) = self.get_ancestor(*hash, block_height, spec) {
-                let current_vote_value = current_votes.get(&ancestor).unwrap_or_else(|| &0);
+                let current_vote_value = current_votes.get(&ancestor).unwrap_or_else(|| &0).clone();
                 current_votes.insert(ancestor, current_vote_value + *votes);
                 total_vote_count += votes;
             }
diff --git a/eth2/fork_choice/src/optimized_lmd_ghost.rs b/eth2/fork_choice/src/optimized_lmd_ghost.rs
index 2c1063a2b..351c4decd 100644
--- a/eth2/fork_choice/src/optimized_lmd_ghost.rs
+++ b/eth2/fork_choice/src/optimized_lmd_ghost.rs
@@ -124,8 +124,9 @@ impl<T: Store, E: EthSpec> OptimizedLMDGhost<T, E> {
                 [log2_int((block_height - target_height - 1u64).as_u64()) as usize]
                 .get(&block_hash)
                 //TODO: Panic if we can't lookup and fork choice fails
-                .expect("All blocks should be added to the ancestor log lookup table");
-            self.get_ancestor(*ancestor_lookup, target_height, &spec)
+                .expect("All blocks should be added to the ancestor log lookup table")
+                .clone();
+            self.get_ancestor(ancestor_lookup, target_height, &spec)
         } {
             // add the result to the cache
             self.cache.insert(cache_key, ancestor);
@@ -151,7 +152,7 @@ impl<T: Store, E: EthSpec> OptimizedLMDGhost<T, E> {
         // these have already been weighted by balance
         for (hash, votes) in latest_votes.iter() {
             if let Some(ancestor) = self.get_ancestor(*hash, block_height, spec) {
-                let current_vote_value = current_votes.get(&ancestor).unwrap_or_else(|| &0);
+                let current_vote_value = current_votes.get(&ancestor).unwrap_or_else(|| &0).clone();
                 current_votes.insert(ancestor, current_vote_value + *votes);
                 total_vote_count += votes;
             }
diff --git a/validator_client/src/error.rs b/validator_client/src/error.rs
index 29d7ba882..97500f900 100644
--- a/validator_client/src/error.rs
+++ b/validator_client/src/error.rs
@@ -1,9 +1,6 @@
 use slot_clock;
 
-use error_chain::{
-    error_chain, error_chain_processing, impl_error_chain_kind, impl_error_chain_processed,
-    impl_extract_backtrace,
-};
+use error_chain::error_chain;
 
 error_chain! {
    links  { }