auto merge of #12900 : alexcrichton/rust/rewrite-sync, r=brson

* Remove clone-ability from all primitives. All shared state will now come
  from the usage of the primitives being shared, not the primitives being
  inherently shareable. This allows for fewer allocations for stack-allocated
  primitives.
* Add `Mutex<T>` and `RWLock<T>` which are stack-allocated primitives for purely
  wrapping a piece of data
* Remove `RWArc<T>` in favor of `Arc<RWLock<T>>`
* Remove `MutexArc<T>` in favor of `Arc<Mutex<T>>`
* Shuffle around where things are located
  * The `arc` module now only contains `Arc`
  * A new `lock` module contains `Mutex`, `RWLock`, and `Barrier`
  * A new `raw` module contains the primitive implementations of `Semaphore`,
    `Mutex`, and `RWLock`
* The Deref/DerefMut trait was implemented where appropriate
* `CowArc` was removed, the functionality is now part of `Arc` and is tagged
  with `#[experimental]`.
* The crate now has #[deny(missing_doc)]
* `Arc` now supports weak pointers

This is not a large-scale rewrite of the functionality contained within the
`sync` crate, but rather a shuffling of who does what an a thinner hierarchy of
ownership to allow for better composability.

Author: bors

src/compiletest/compiletest.rs

@@ -12,7 +12,6 @@
 #[feature(phase)];
 
 #[allow(non_camel_case_types)];
-#[allow(deprecated_owned_vector)]; // NOTE: remove after stage0
 #[deny(warnings)];
 
 extern crate test;

src/doc/guide-tasks.md

@@ -359,7 +359,7 @@ fn main() {
 
         spawn(proc() {
             let local_arc : Arc<~[f64]> = rx.recv();
-            let task_numbers = local_arc.get();
+            let task_numbers = &*local_arc;
             println!("{}-norm = {}", num, pnorm(task_numbers, num));
         });
     }
@@ -411,7 +411,7 @@ Each task recovers the underlying data by
 # let (tx, rx) = channel();
 # tx.send(numbers_arc.clone());
 # let local_arc : Arc<~[f64]> = rx.recv();
-let task_numbers = local_arc.get();
+let task_numbers = &*local_arc;
 # }
 ~~~
 

src/driver/driver.rs

@@ -14,9 +14,4 @@ extern crate this = "rustdoc";
 #[cfg(rustc)]
 extern crate this = "rustc";
 
-#[cfg(not(stage0))]
 fn main() { this::main() }
-
-#[cfg(stage0)]
-#[start]
-fn start(argc: int, argv: **u8) -> int { native::start(argc, argv, this::main) }

src/etc/licenseck.py

@@ -41,7 +41,7 @@
     "libstd/sync/mpsc_queue.rs", # BSD
     "libstd/sync/spsc_queue.rs", # BSD
     "libstd/sync/mpmc_bounded_queue.rs", # BSD
-    "libsync/sync/mpsc_intrusive.rs", # BSD
+    "libsync/mpsc_intrusive.rs", # BSD
 ]
 
 def check_license(name, contents):

src/libgreen/lib.rs

@@ -207,16 +207,6 @@ pub mod sleeper_list;
 pub mod stack;
 pub mod task;
 
-#[lang = "start"]
-#[cfg(not(test), stage0)]
-pub fn lang_start(main: *u8, argc: int, argv: **u8) -> int {
-    use std::cast;
-    start(argc, argv, proc() {
-        let main: extern "Rust" fn() = unsafe { cast::transmute(main) };
-        main();
-    })
-}
-
 /// Set up a default runtime configuration, given compiler-supplied arguments.
 ///
 /// This function will block until the entire pool of M:N schedulers have

src/libgreen/simple.rs

@@ -40,7 +40,7 @@ impl Runtime for SimpleTask {
         // See libnative/task.rs for what's going on here with the `awoken`
         // field and the while loop around wait()
         unsafe {
-            let mut guard = (*me).lock.lock();
+            let guard = (*me).lock.lock();
             (*me).awoken = false;
             match f(task) {
                 Ok(()) => {
@@ -60,7 +60,7 @@ impl Runtime for SimpleTask {
         to_wake.put_runtime(self as ~Runtime);
         unsafe {
             cast::forget(to_wake);
-            let mut guard = (*me).lock.lock();
+            let guard = (*me).lock.lock();
             (*me).awoken = true;
             guard.signal();
         }

src/libnative/io/timer_helper.rs

@@ -75,7 +75,7 @@ pub fn send(req: Req) {
 fn shutdown() {
     // Request a shutdown, and then wait for the task to exit
     unsafe {
-        let mut guard = TIMER_HELPER_EXIT.lock();
+        let guard = TIMER_HELPER_EXIT.lock();
         send(Shutdown);
         guard.wait();
         drop(guard);

src/libnative/lib.rs

@@ -69,7 +69,7 @@ static OS_DEFAULT_STACK_ESTIMATE: uint = 1 << 20;
 static OS_DEFAULT_STACK_ESTIMATE: uint = 2 * (1 << 20);
 
 #[lang = "start"]
-#[cfg(not(test), not(stage0))]
+#[cfg(not(test))]
 pub fn lang_start(main: *u8, argc: int, argv: **u8) -> int {
     use std::cast;
     start(argc, argv, proc() {

src/libnative/task.rs

@@ -190,7 +190,7 @@ impl rt::Runtime for Ops {
             let task = BlockedTask::block(cur_task);
 
             if times == 1 {
-                let mut guard = (*me).lock.lock();
+                let guard = (*me).lock.lock();
                 (*me).awoken = false;
                 match f(task) {
                     Ok(()) => {
@@ -202,7 +202,7 @@ impl rt::Runtime for Ops {
                 }
             } else {
                 let mut iter = task.make_selectable(times);
-                let mut guard = (*me).lock.lock();
+                let guard = (*me).lock.lock();
                 (*me).awoken = false;
                 let success = iter.all(|task| {
                     match f(task) {
@@ -232,7 +232,7 @@ impl rt::Runtime for Ops {
             let me = &mut *self as *mut Ops;
             to_wake.put_runtime(self as ~rt::Runtime);
             cast::forget(to_wake);
-            let mut guard = (*me).lock.lock();
+            let guard = (*me).lock.lock();
             (*me).awoken = true;
             guard.signal();
         }

src/librustdoc/html/format.rs

@@ -208,8 +208,8 @@ fn path(w: &mut io::Writer, path: &clean::Path, print_all: bool,
         let loc = loc.unwrap();
 
         local_data::get(cache_key, |cache| {
-            let cache = cache.unwrap().get();
-            let abs_root = root(cache, loc.as_slice());
+            let cache = cache.unwrap();
+            let abs_root = root(&**cache, loc.as_slice());
             let rel_root = match path.segments.get(0).name.as_slice() {
                 "self" => Some(~"./"),
                 _ => None,
@@ -241,7 +241,7 @@ fn path(w: &mut io::Writer, path: &clean::Path, print_all: bool,
                 }
             }
 
-            match info(cache) {
+            match info(&**cache) {
                 // This is a documented path, link to it!
                 Some((ref fqp, shortty)) if abs_root.is_some() => {
                     let mut url = abs_root.unwrap();
@@ -301,7 +301,7 @@ impl fmt::Show for clean::Type {
         match *self {
             clean::TyParamBinder(id) | clean::Generic(id) => {
                 local_data::get(cache_key, |cache| {
-                    let m = cache.unwrap().get();
+                    let m = cache.unwrap();
                     f.buf.write(m.typarams.get(&id).as_bytes())
                 })
             }

src/librustdoc/html/render.rs

@@ -1265,7 +1265,7 @@ fn item_trait(w: &mut Writer, it: &clean::Item,
     }
 
     local_data::get(cache_key, |cache| {
-        let cache = cache.unwrap().get();
+        let cache = cache.unwrap();
         match cache.implementors.find(&it.id) {
             Some(implementors) => {
                 try!(write!(w, "
@@ -1496,7 +1496,7 @@ fn render_struct(w: &mut Writer, it: &clean::Item,
 
 fn render_methods(w: &mut Writer, it: &clean::Item) -> fmt::Result {
     local_data::get(cache_key, |cache| {
-        let c = cache.unwrap().get();
+        let c = cache.unwrap();
         match c.impls.find(&it.id) {
             Some(v) => {
                 let mut non_trait = v.iter().filter(|p| {
@@ -1576,7 +1576,7 @@ fn render_impl(w: &mut Writer, i: &clean::Impl,
             Some(id) => id,
         };
         try!(local_data::get(cache_key, |cache| {
-            let cache = cache.unwrap().get();
+            let cache = cache.unwrap();
             match cache.traits.find(&trait_id) {
                 Some(t) => {
                     let name = meth.name.clone();
@@ -1606,7 +1606,7 @@ fn render_impl(w: &mut Writer, i: &clean::Impl,
         None => {}
         Some(id) => {
             try!(local_data::get(cache_key, |cache| {
-                let cache = cache.unwrap().get();
+                let cache = cache.unwrap();
                 match cache.traits.find(&id) {
                     Some(t) => {
                         for method in t.methods.iter() {

src/libstd/comm/shared.rs

@@ -68,7 +68,7 @@ pub enum Failure {
 impl<T: Send> Packet<T> {
     // Creation of a packet *must* be followed by a call to inherit_blocker
     pub fn new() -> Packet<T> {
-        let mut p = Packet {
+        let p = Packet {
             queue: mpsc::Queue::new(),
             cnt: atomics::AtomicInt::new(0),
             steals: 0,

src/libstd/intrinsics.rs

@@ -164,7 +164,6 @@ pub trait TyVisitor {
     fn visit_self(&mut self) -> bool;
 }
 
-
 extern "rust-intrinsic" {
 
     // NB: These intrinsics take unsafe pointers because they mutate aliased

src/libstd/rt/bookkeeping.rs

@@ -34,7 +34,7 @@ pub fn increment() {
 pub fn decrement() {
     unsafe {
         if TASK_COUNT.fetch_sub(1, atomics::SeqCst) == 1 {
-            let mut guard = TASK_LOCK.lock();
+            let guard = TASK_LOCK.lock();
             guard.signal();
         }
     }
@@ -44,7 +44,7 @@ pub fn decrement() {
 /// the entry points of native programs
 pub fn wait_for_other_tasks() {
     unsafe {
-        let mut guard = TASK_LOCK.lock();
+        let guard = TASK_LOCK.lock();
         while TASK_COUNT.load(atomics::SeqCst) > 0 {
             guard.wait();
         }

src/libstd/sync/atomics.rs

@@ -39,8 +39,7 @@
 //!
 //! A simple spinlock:
 //!
-//! ```ignore
-//! # // FIXME: Needs PR #12430
+//! ```
 //! extern crate sync;
 //!
 //! use sync::Arc;
@@ -68,8 +67,7 @@
 //!
 //! Transferring a heap object with `AtomicOption`:
 //!
-//! ```ignore
-//! # // FIXME: Needs PR #12430
+//! ```
 //! extern crate sync;
 //!
 //! use sync::Arc;