docs: remove mentions of Gc.
@@ -3381,7 +3381,7 @@ fn main() {
```
-Patterns can also dereference pointers by using the `&`, `box` or `@` symbols,
+Patterns can also dereference pointers by using the `&`, `box` symbols,
as appropriate. For example, these two matches on `x: &int` are equivalent:
```
