Auto merge of #454 - alexcrichton:bump-rust, r=posborne

Bump minimum supported version of Rust

Many crates are coalescing around 1.9.0 with the stabilization of `std::panic`,
and it helps remove the build script w/ rustc version parsing for now as well.

Author: homu

Cargo.toml

@@ -14,8 +14,6 @@ exclude     = [
   "test/**/*"
 ]
 
-build = "build.rs"
-
 [features]
 eventfd = []
 execvpe = []
@@ -28,10 +26,6 @@ bitflags = "0.4"
 cfg-if = "0.1.0"
 void = "1.0.2"
 
-[build-dependencies]
-rustc_version = "0.1.7"
-semver = "0.1.20"  # Old version for compatibility with rustc_version.
-
 [dev-dependencies]
 rand = "0.3.8"
 tempdir = "0.3"

build.rs

@@ -311,7 +311,6 @@ impl AsRef<libc::sigset_t> for SigSet {
 }
 
 #[allow(unknown_lints)]
-#[cfg_attr(not(raw_pointer_derive_allowed), allow(raw_pointer_derive))]
 #[derive(Clone, Copy, PartialEq)]
 pub enum SigHandler {
     SigDfl,