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

1 files changed, 4 insertions, 6 deletions

diff --git a/src/test/run-make/simd-ffi/simd.rs b/src/test/run-make/simd-ffi/simd.rs
index 563fe79e537..5576e882371 100644
--- a/src/test/run-make/simd-ffi/simd.rs
+++ b/src/test/run-make/simd-ffi/simd.rs
@@ -12,8 +12,8 @@
 #![crate_type = "lib"]
 // we can compile to a variety of platforms, because we don't need
 // cross-compiled standard libraries.
-#![feature(no_std)]
-#![no_std]
+#![feature(no_core)]
+#![no_core]
 
 #![feature(simd, simd_ffi, link_llvm_intrinsics, lang_items)]
 
@@ -75,8 +75,6 @@ pub trait Sized { }
 #[lang = "copy"]
 pub trait Copy { }
 
-mod core {
-    pub mod marker {
-        pub use Copy;
-    }
+pub mod marker {
+    pub use Copy;
 }