syntax: Implement #![no_core]

This commit is an implementation of [RFC 1184][rfc] which tweaks the behavior of
the `#![no_std]` attribute and adds a new `#![no_core]` attribute. The
`#![no_std]` attribute now injects `extern crate core` at the top of the crate
as well as the libcore prelude into all modules (in the same manner as the
standard library's prelude). The `#![no_core]` attribute disables both std and
core injection.

[rfc]: https://github.com/rust-lang/rfcs/pull/1184

2 files changed, 4 insertions, 3 deletions

diff --git a/src/libcore/hash/mod.rs b/src/libcore/hash/mod.rs
index e35f380d06f..34bc3b835a1 100644
--- a/src/libcore/hash/mod.rs
+++ b/src/libcore/hash/mod.rs
@@ -62,7 +62,7 @@
 
 #![stable(feature = "rust1", since = "1.0.0")]
 
-use prelude::*;
+use prelude::v1::*;
 
 use mem;
 
@@ -183,7 +183,7 @@ pub fn hash<T: Hash, H: Hasher + Default>(value: &T) -> u64 {
 //////////////////////////////////////////////////////////////////////////////
 
 mod impls {
-    use prelude::*;
+    use prelude::v1::*;
 
     use slice;
     use super::*;
diff --git a/src/libcore/hash/sip.rs b/src/libcore/hash/sip.rs
index 93bdadff549..4dcd513a0d2 100644
--- a/src/libcore/hash/sip.rs
+++ b/src/libcore/hash/sip.rs
@@ -10,8 +10,9 @@
 
 //! An implementation of SipHash 2-4.
 
+use prelude::v1::*;
+
 use ptr;
-use prelude::*;
 use super::Hasher;
 
 /// An implementation of SipHash 2-4.