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]

3 files changed, 21 insertions, 18 deletions

diff --git a/src/librustrt/local_data.rs b/src/librustrt/local_data.rs
index 1a7f0cdfc50..215c0992bc0 100644
--- a/src/librustrt/local_data.rs
+++ b/src/librustrt/local_data.rs
@@ -274,6 +274,7 @@ impl<T: 'static> Drop for Ref<T> {
 #[cfg(test)]
 mod tests {
     use std::prelude::*;
+    use std::gc::{Gc, GC};
     use super::*;
     use std::task;
 
@@ -329,11 +330,11 @@ mod tests {
     #[test]
     fn test_tls_multiple_types() {
         static str_key: Key<String> = &Key;
-        static box_key: Key<@()> = &Key;
+        static box_key: Key<Gc<()>> = &Key;
         static int_key: Key<int> = &Key;
         task::spawn(proc() {
             str_key.replace(Some("string data".to_string()));
-            box_key.replace(Some(@()));
+            box_key.replace(Some(box(GC) ()));
             int_key.replace(Some(42));
         });
     }
@@ -341,13 +342,13 @@ mod tests {
     #[test]
     fn test_tls_overwrite_multiple_types() {
         static str_key: Key<String> = &Key;
-        static box_key: Key<@()> = &Key;
+        static box_key: Key<Gc<()>> = &Key;
         static int_key: Key<int> = &Key;
         task::spawn(proc() {
             str_key.replace(Some("string data".to_string()));
             str_key.replace(Some("string data 2".to_string()));
-            box_key.replace(Some(@()));
-            box_key.replace(Some(@()));
+            box_key.replace(Some(box(GC) ()));
+            box_key.replace(Some(box(GC) ()));
             int_key.replace(Some(42));
             // This could cause a segfault if overwriting-destruction is done
             // with the crazy polymorphic transmute rather than the provided
@@ -360,13 +361,13 @@ mod tests {
     #[should_fail]
     fn test_tls_cleanup_on_failure() {
         static str_key: Key<String> = &Key;
-        static box_key: Key<@()> = &Key;
+        static box_key: Key<Gc<()>> = &Key;
         static int_key: Key<int> = &Key;
         str_key.replace(Some("parent data".to_string()));
-        box_key.replace(Some(@()));
+        box_key.replace(Some(box(GC) ()));
         task::spawn(proc() {
             str_key.replace(Some("string data".to_string()));
-            box_key.replace(Some(@()));
+            box_key.replace(Some(box(GC) ()));
             int_key.replace(Some(42));
             fail!();
         });
diff --git a/src/librustrt/local_heap.rs b/src/librustrt/local_heap.rs
index 52fe5c35a26..d09033e771c 100644
--- a/src/librustrt/local_heap.rs
+++ b/src/librustrt/local_heap.rs
@@ -317,14 +317,15 @@ pub unsafe fn local_free(ptr: *u8) {
 mod bench {
     extern crate test;
     use self::test::Bencher;
+    use std::gc::GC;
 
     #[bench]
     fn alloc_managed_small(b: &mut Bencher) {
-        b.iter(|| { @10; });
+        b.iter(|| { box(GC) 10 });
     }
 
     #[bench]
     fn alloc_managed_big(b: &mut Bencher) {
-        b.iter(|| { @([10, ..1000]); });
+        b.iter(|| { box(GC) ([10, ..1000]) });
     }
 }
diff --git a/src/librustrt/task.rs b/src/librustrt/task.rs
index bde14b962c7..e99703a1f58 100644
--- a/src/librustrt/task.rs
+++ b/src/librustrt/task.rs
@@ -397,10 +397,11 @@ mod test {
     use super::*;
     use std::prelude::*;
     use std::task;
+    use std::gc::{Gc, GC};
 
     #[test]
     fn local_heap() {
-        let a = @5;
+        let a = box(GC) 5;
         let b = a;
         assert!(*a == 5);
         assert!(*b == 5);
@@ -408,11 +409,11 @@ mod test {
 
     #[test]
     fn tls() {
-        local_data_key!(key: @String)
-        key.replace(Some(@"data".to_string()));
+        local_data_key!(key: Gc<String>)
+        key.replace(Some(box(GC) "data".to_string()));
         assert_eq!(key.get().unwrap().as_slice(), "data");
-        local_data_key!(key2: @String)
-        key2.replace(Some(@"data".to_string()));
+        local_data_key!(key2: Gc<String>)
+        key2.replace(Some(box(GC) "data".to_string()));
         assert_eq!(key2.get().unwrap().as_slice(), "data");
     }
 
@@ -452,11 +453,11 @@ mod test {
         use std::cell::RefCell;
 
         struct List {
-            next: Option<@RefCell<List>>,
+            next: Option<Gc<RefCell<List>>>,
         }
 
-        let a = @RefCell::new(List { next: None });
-        let b = @RefCell::new(List { next: Some(a) });
+        let a = box(GC) RefCell::new(List { next: None });
+        let b = box(GC) RefCell::new(List { next: Some(a) });
 
         {
             let mut a = a.borrow_mut();