servo/components/script/dom/bindings/codegen
bors-servo 80cb0cf821 Auto merge of #11872 - eddyb:back-to-roots, r=Ms2ger
Replace return_address usage for rooting with stack guards and convenience macros.

The existing `Rooted` and `RootedVec` users were migrated the the following two macros:
```rust
let x = Rooted::new(cx, value);
// Was changed to:
rooted!(in(cx) let x = value);
// Which expands to:
let mut __root = Rooted::new_unrooted(value);
let x = RootedGuard::new(cx, &mut __root);
```
```rust
let mut v = RootedVec::new();
v.extend(iterator);
// Was changed to:
rooted_vec!(let v <- iterator);
// Which expands to:
let mut __root = RootableVec::new();
let v = RootedVec::new(&mut __root, iterator);
```

The `rooted!` macro depends on servo/rust-mozjs#272.
These APIs based on two types, a container to be rooted and a rooting guard, allow implementing both `Rooted`-style rooting and `Traceable`-based rooting in stable Rust, without abusing `return_address`.

Such macros may have been tried before, but in 1.9 their hygiene is broken, they work only since 1.10.

Sadly, `Rooted` is a FFI type and completely exposed, so I cannot prevent anyone from creating their own, although all fields but the value get overwritten by `RootedGuard::new` anyway.
`RootableVec` OTOH is *guaranteed* to be empty when not rooted, which makes it harmless AFAICT.

By fixing rust-lang/rust#34227, this PR enables Servo to build with `-Zorbit`.

---
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix rust-lang/rust#34227
- [x] These changes do not require tests because they are not functional changes

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2016-07-04 11:03:35 -07:00
..
parser Update the WebIDL parser 2016-05-18 11:30:53 +02:00
ply Cargoify servo 2014-09-08 20:21:42 -06:00
BindingGen.py Remove unused command-line Python codegen arguments 2016-01-07 08:51:06 -05:00
Bindings.conf Support WindowProxy return values in bindings 2016-06-09 23:42:27 +02:00
CodegenRust.py Auto merge of #11872 - eddyb:back-to-roots, r=Ms2ger 2016-07-04 11:03:35 -07:00
Configuration.py Support WindowProxy return values in bindings 2016-06-09 23:42:27 +02:00
GlobalGen.py Lazily define interface objects on globals (fixes #6419) 2016-02-25 15:56:47 +01:00