rustc: Obsolete the @ syntax entirely

This removes all remnants of `@` pointers from rustc. Additionally, this removes
the `GC` structure from the prelude as it seems odd exporting an experimental
type in the prelude by default.

Closes #14193
[breaking-change]

src/librustc/front/config.rs

@@ -12,7 +12,7 @@ use syntax::fold::Folder;
 use syntax::{ast, fold, attr};
 use syntax::codemap;
 
-use std::gc::Gc;
+use std::gc::{Gc, GC};
 
 struct Context<'a> {
     in_cfg: |attrs: &[ast::Attribute]|: 'a -> bool,

src/librustc/front/std_inject.rs

@@ -23,7 +23,7 @@ use syntax::parse::token;
 use syntax::util::small_vector::SmallVector;
 
 use std::mem;
-use std::gc::Gc;
+use std::gc::{Gc, GC};
 
 pub static VERSION: &'static str = "0.11.0-pre";
 

src/librustc/front/test.rs

@@ -18,7 +18,7 @@ use front::config;
 use front::std_inject::with_version;
 
 use std::cell::RefCell;
-use std::gc::Gc;
+use std::gc::{Gc, GC};
 use std::slice;
 use std::vec;
 use syntax::ast_util::*;

src/librustc/middle/astencode.rs

@@ -40,7 +40,7 @@ use libc;
 use std::io::Seek;
 use std::io::MemWriter;
 use std::mem;
-use std::string::String;
+use std::gc::GC;
 
 use serialize::ebml::reader;
 use serialize::ebml;

src/librustc/middle/borrowck/mod.rs

@@ -23,6 +23,7 @@ use util::ppaux::{note_and_explain_region, Repr, UserString};
 use std::cell::{Cell};
 use std::ops::{BitOr, BitAnd};
 use std::rc::Rc;
+use std::gc::{Gc, GC};
 use std::string::String;
 use syntax::ast;
 use syntax::ast_map;
@@ -70,7 +71,7 @@ pub fn check_crate(tcx: &ty::ctxt,
                    krate: &ast::Crate) {
     let mut bccx = BorrowckCtxt {
         tcx: tcx,
-        stats: @BorrowStats {
+        stats: box(GC) BorrowStats {
             loaned_paths_same: Cell::new(0),
             loaned_paths_imm: Cell::new(0),
             stable_paths: Cell::new(0),
@@ -155,7 +156,7 @@ pub struct BorrowckCtxt<'a> {
     tcx: &'a ty::ctxt,
 
     // Statistics:
-    stats: @BorrowStats
+    stats: Gc<BorrowStats>,
 }
 
 pub struct BorrowStats {

src/librustc/middle/check_match.rs

@@ -19,7 +19,7 @@ use middle::ty;
 use util::ppaux::ty_to_str;
 
 use std::cmp;
-use std::gc::Gc;
+use std::gc::{Gc, GC};
 use std::iter;
 use syntax::ast::*;
 use syntax::ast_util::{is_unguarded, walk_pat};

src/librustc/middle/check_static.rs

@@ -123,7 +123,7 @@ impl<'a> Visitor<bool> for CheckStaticVisitor<'a> {
             ast::ExprUnary(ast::UnUniq, _) |
             ast::ExprVstore(_, ast::ExprVstoreUniq) => {
                 self.tcx.sess.span_err(e.span,
-                                   "static items are not allowed to have owned pointers");
+                                   "static items are not allowed to have custom pointers");
             }
             _ => {
                 let node_ty = ty::node_id_to_type(self.tcx, e.id);

src/librustc/middle/kind.rs

@@ -245,9 +245,12 @@ pub fn check_expr(cx: &mut Context, e: &Expr) {
     check_bounds_on_type_parameters(cx, e);
 
     match e.node {
-        ExprUnary(UnBox, ref interior) => {
-            let interior_type = ty::expr_ty(cx.tcx, &**interior);
-            let _ = check_static(cx.tcx, interior_type, interior.span);
+        ExprBox(ref loc, ref interior) => {
+            let def = ty::resolve_expr(cx.tcx, &**loc);
+            if Some(def.def_id()) == cx.tcx.lang_items.managed_heap() {
+                let interior_type = ty::expr_ty(cx.tcx, &**interior);
+                let _ = check_static(cx.tcx, interior_type, interior.span);
+            }
         }
         ExprCast(ref source, _) => {
             let source_ty = ty::expr_ty(cx.tcx, &**source);

src/librustc/middle/resolve.rs

@@ -35,7 +35,7 @@ use syntax::visit::Visitor;
 
 use std::collections::{HashMap, HashSet};
 use std::cell::{Cell, RefCell};
-use std::gc::Gc;
+use std::gc::{Gc, GC};
 use std::mem::replace;
 use std::rc::{Rc, Weak};
 use std::uint;

src/librustc/middle/trans/_match.rs

@@ -226,7 +226,7 @@ use util::ppaux::{Repr, vec_map_to_str};
 use std::collections::HashMap;
 use std::cell::Cell;
 use std::rc::Rc;
-use std::gc::Gc;
+use std::gc::{Gc, GC};
 use syntax::ast;
 use syntax::ast::Ident;
 use syntax::ast_util::path_to_ident;

src/librustc/middle/typeck/infer/error_reporting.rs

@@ -60,6 +60,7 @@ time of error detection.
 */
 
 use std::collections::HashSet;
+use std::gc::GC;
 use middle::def;
 use middle::subst;
 use middle::ty;