diff --git a/ethcore/src/executive.rs b/ethcore/src/executive.rs
index fc2f837ef..bd30e0fb6 100644
--- a/ethcore/src/executive.rs
+++ b/ethcore/src/executive.rs
@@ -140,10 +140,8 @@ impl<'a> Executive<'a> {
 		let init_gas = t.gas - base_gas_required;
 
 		// validate transaction nonce
-		if check_nonce {
-			if t.nonce != nonce {
-				return Err(From::from(ExecutionError::InvalidNonce { expected: nonce, got: t.nonce }));
-			}
+		if check_nonce && t.nonce != nonce {
+			return Err(From::from(ExecutionError::InvalidNonce { expected: nonce, got: t.nonce }));
 		}
 
 		// validate if transaction fits into given block
diff --git a/ethcore/src/externalities.rs b/ethcore/src/externalities.rs
index e5e232a98..1c0bb417f 100644
--- a/ethcore/src/externalities.rs
+++ b/ethcore/src/externalities.rs
@@ -67,6 +67,8 @@ pub struct Externalities<'a, T> where T: 'a + Tracer {
 }
 
 impl<'a, T> Externalities<'a, T> where T: 'a + Tracer {
+
+	#[cfg_attr(feature="dev", allow(too_many_arguments))]
 	/// Basic `Externalities` constructor.
 	pub fn new(state: &'a mut State,
 		env_info: &'a EnvInfo,
diff --git a/ethcore/src/substate.rs b/ethcore/src/substate.rs
index f643fea07..65b314663 100644
--- a/ethcore/src/substate.rs
+++ b/ethcore/src/substate.rs
@@ -19,7 +19,7 @@ use common::*;
 
 /// State changes which should be applied in finalize,
 /// after transaction is fully executed.
-#[derive(Debug)]
+#[derive(Debug, Default)]
 pub struct Substate {
 	/// Any accounts that have suicided.
 	pub suicides: HashSet<Address>,
diff --git a/ethcore/src/trace/trace.rs b/ethcore/src/trace/trace.rs
index b0e2e75f5..6a90aaf8a 100644
--- a/ethcore/src/trace/trace.rs
+++ b/ethcore/src/trace/trace.rs
@@ -17,7 +17,7 @@
 //! Tracing datatypes.
 use common::*;
 
-/// TraceCall result.
+/// `TraceCall` result.
 #[derive(Debug, Clone, PartialEq, Default)]
 pub struct TraceCallResult {
 	/// Gas used by call.
@@ -26,7 +26,7 @@ pub struct TraceCallResult {
 	pub output: Bytes,
 }
 
-/// TraceCreate result.
+/// `TraceCreate` result.
 #[derive(Debug, Clone, PartialEq)]
 pub struct TraceCreateResult {
 	/// Gas used by create.
diff --git a/parity/upgrade.rs b/parity/upgrade.rs
index c9c98e174..da01c039e 100644
--- a/parity/upgrade.rs
+++ b/parity/upgrade.rs
@@ -22,6 +22,7 @@ use std::fs::File;
 use std::env;
 use std::io::{Read, Write};
 
+#[cfg_attr(feature="dev", allow(enum_variant_names))]
 #[derive(Debug)]
 pub enum Error {
 	CannotLockVersionFile,
@@ -107,16 +108,12 @@ fn with_locked_version<F>(script: F) -> Result<usize, Error>
 			})
 			.unwrap_or_else(|| Version::parse("0.9.0").unwrap());
 
-	let script_result = {
-		let mut lock = try!(File::create(&path).map_err(|_| Error::CannotLockVersionFile));
-		let result = script(&version);
+	let mut lock = try!(File::create(&path).map_err(|_| Error::CannotLockVersionFile));
+	let result = script(&version);
 
-		let written_version = Version::parse(CURRENT_VERSION).unwrap();
-		try!(lock.write_all(written_version.to_string().as_bytes()).map_err(|_| Error::CannotUpdateVersionFile));
-		result
-	};
-
-	script_result
+	let written_version = Version::parse(CURRENT_VERSION).unwrap();
+	try!(lock.write_all(written_version.to_string().as_bytes()).map_err(|_| Error::CannotUpdateVersionFile));
+	result
 }
 
 pub fn upgrade() -> Result<usize, Error> {