Update to current Rust nightly

Notably, this lets us use bytestring literals (with a slightly awkward
double-cast).

src/bash.rs

@@ -1,6 +1,6 @@
-extern crate libc;
+#![allow(non_camel_case_types, dead_code)]
 
-// command.h
+extern crate libc;
 
 #[repr(C)]
 pub struct word_desc {
@@ -15,7 +15,7 @@ pub struct word_list {
 
 // general.h
 
-type sh_builtin_func_t = extern fn (*mut word_list) -> libc::c_int;
+pub type sh_builtin_func_t = extern fn (*mut word_list) -> libc::c_int;
 
 // builtins.h
 

src/lib.rs

@@ -1,17 +1,20 @@
+#![feature(libc)]
+
 extern crate libc;
+
 mod bash;
 
-extern fn builtin_lulz(args: *mut bash::word_list) -> libc::c_int {
+extern fn builtin_lulz(_: *mut bash::word_list) -> libc::c_int {
     println!("lulz");
     0
 }
 
 #[no_mangle]
 pub static mut lulz_struct: bash::builtin = bash::builtin {
-    name: &['l' as i8, 'u' as i8, 'l' as i8, 'z' as i8, 0 as i8] as *const i8,
+    name: b"lulz\0" as *const u8 as *const libc::c_char,
     function: builtin_lulz,
     flags: bash::BUILTIN_ENABLED,
-    long_doc: 0 as *const *const i8,
-    short_doc: &['l' as i8, 'o' as i8, 'l' as i8, 'w' as i8, 'u' as i8, 't' as i8, 0 as i8] as *const i8,
+    long_doc: 0 as *const *const libc::c_char,
+    short_doc: b"lolwut\0" as *const u8 as *const libc::c_char,
     handle: 0 as *const i8,
 };