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]

1 files changed, 4 insertions, 1 deletions

diff --git a/src/libhexfloat/lib.rs b/src/libhexfloat/lib.rs
index b181b0ca8c9..5451e4fc18c 100644
--- a/src/libhexfloat/lib.rs
+++ b/src/libhexfloat/lib.rs
@@ -57,6 +57,8 @@ use syntax::parse;
 use syntax::parse::token;
 use rustc::plugin::Registry;
 
+use std::gc::Gc;
+
 #[plugin_registrar]
 pub fn plugin_registrar(reg: &mut Registry) {
     reg.register_macro("hexfloat", expand_syntax_ext);
@@ -163,7 +165,8 @@ struct Ident {
     span: Span
 }
 
-fn parse_tts(cx: &ExtCtxt, tts: &[ast::TokenTree]) -> (@ast::Expr, Option<Ident>) {
+fn parse_tts(cx: &ExtCtxt,
+             tts: &[ast::TokenTree]) -> (Gc<ast::Expr>, Option<Ident>) {
     let p = &mut parse::new_parser_from_tts(cx.parse_sess(),
                                             cx.cfg(),
                                             tts.iter()