Require &Crate instead of @Crate

This help enable some later refactorings.

src/librustc/middle/lint.rs

@@ -135,7 +135,7 @@ pub type LintDict = HashMap<&'static str, LintSpec>;
 enum AttributedNode<'self> {
     Item(@ast::item),
     Method(&'self ast::method),
-    Crate(@ast::Crate),
+    Crate(&'self ast::Crate),
 }
 
 #[deriving(Eq)]
@@ -1565,7 +1565,7 @@ impl Visitor<@mut Context> for LintCheckVisitor {
     }
 }
 
-pub fn check_crate(tcx: ty::ctxt, crate: @ast::Crate) {
+pub fn check_crate(tcx: ty::ctxt, crate: &ast::Crate) {
     let cx = @mut Context {
         dict: @get_lint_dict(),
         curr: SmallIntMap::new(),

src/librustc/middle/reachable.rs

@@ -268,7 +268,7 @@ impl ReachableContext {
 
     // Step 1: Mark all public symbols, and add all public symbols that might
     // be inlined to a worklist.
-    fn mark_public_symbols(&self, crate: @Crate) {
+    fn mark_public_symbols(&self, crate: &Crate) {
         let reachable_symbols = self.reachable_symbols;
         let worklist = self.worklist;
 
@@ -429,7 +429,7 @@ impl ReachableContext {
 
 pub fn find_reachable(tcx: ty::ctxt,
                       method_map: typeck::method_map,
-                      crate: @Crate)
+                      crate: &Crate)
                       -> @mut HashSet<NodeId> {
     // XXX(pcwalton): We only need to mark symbols that are exported. But this
     // is more complicated than just looking at whether the symbol is `pub`,