Fixing clippy warnings. When building on nightly it is required to enable clippy

rpc/Cargo.toml

@@ -26,8 +26,9 @@ serde_macros = { version = "0.7.0", optional = true }
 [build-dependencies]
 serde_codegen = { version = "0.7.0", optional = true }
 syntex = "0.29.0"
+rustc_version = "0.1"
 
 [features]
 default = ["serde_codegen"]
 nightly = ["serde_macros"]
-dev = ["clippy", "ethcore/dev", "ethcore-util/dev", "ethsync/dev"]
+dev = ["ethcore/dev", "ethcore-util/dev", "ethsync/dev"]

rpc/build.rs

@@ -1,3 +1,23 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+extern crate rustc_version;
+
+use rustc_version::{version_meta, Channel};
+
 #[cfg(not(feature = "serde_macros"))]
 mod inner {
     extern crate syntex;
@@ -26,4 +46,7 @@ mod inner {
 
 fn main() {
     inner::main();
+	if let Channel::Nightly = version_meta().channel {
+		println!("cargo:rustc-cfg=nightly");
+	}
 }