Fixing warnings

ethcore/src/trace/executive_tracer.rs

@@ -117,7 +117,7 @@ impl VMTracer for ExecutiveVMTracer {
 		self.data.operations.push(VMOperation {
 			pc: pc,
 			instruction: instruction,
-			gas_cost: gas_cost.clone(),	
+			gas_cost: gas_cost.clone(),
 			executed: None,
 		});
 		true
@@ -133,10 +133,10 @@ impl VMTracer for ExecutiveVMTracer {
 		self.data.operations.last_mut().expect("trace_executed is always called after a trace_prepare_execute").executed = Some(ex);
 	}
 
-	fn prepare_subtrace(&self, code: &Bytes) -> Self {
+	fn prepare_subtrace(&self, code: &[u8]) -> Self {
 		ExecutiveVMTracer { data: VMTrace {
 			parent_step: self.data.operations.len(),
-			code: code.clone(),
+			code: code.to_vec(),
 			operations: vec![],
 			subs: vec![],
 		}}

ethcore/src/trace/mod.rs

@@ -98,7 +98,7 @@ pub trait VMTracer: Send {
 	fn trace_executed(&mut self, _gas_used: U256, _stack_push: &[U256], _mem_diff: Option<(usize, &[u8])>, _store_diff: Option<(U256, U256)>) {}
 
 	/// Spawn subtracer which will be used to trace deeper levels of execution.
-	fn prepare_subtrace(&self, code: &Bytes) -> Self where Self: Sized;
+	fn prepare_subtrace(&self, code: &[u8]) -> Self where Self: Sized;
 
 	/// Spawn subtracer which will be used to trace deeper levels of execution.
 	fn done_subtrace(&mut self, sub: Self) where Self: Sized;

ethcore/src/trace/noop_tracer.rs

@@ -75,7 +75,7 @@ impl VMTracer for NoopVMTracer {
 	fn trace_executed(&mut self, _gas_used: U256, _stack_push: &[U256], _mem_diff: Option<(usize, &[u8])>, _store_diff: Option<(U256, U256)>) {}
 
 	/// Spawn subtracer which will be used to trace deeper levels of execution.
-	fn prepare_subtrace(&self, _code: &Bytes) -> Self { NoopVMTracer }
+	fn prepare_subtrace(&self, _code: &[u8]) -> Self { NoopVMTracer }
 
 	/// Spawn subtracer which will be used to trace deeper levels of execution.
 	fn done_subtrace(&mut self, _sub: Self) {}