auto merge of #10603 : alexcrichton/rust/no-linked-failure, r=brson

The reasons for doing this are:

* The model on which linked failure is based is inherently complex
* The implementation is also very complex, and there are few remaining who
  fully understand the implementation
* There are existing race conditions in the core context switching function of
  the scheduler, and possibly others.
* It's unclear whether this model of linked failure maps well to a 1:1 threading
  model

Linked failure is often a desired aspect of tasks, but we would like to take a
much more conservative approach in re-implementing linked failure if at all.

Closes #8674
Closes #8318
Closes #8863

src/test/bench/shootout-k-nucleotide-pipes.rs

@@ -179,9 +179,9 @@ fn main() {
 
         let (from_parent, to_child) = comm::stream();
 
-        do task::spawn_with(from_parent) |from_parent| {
+        do spawn {
             make_sequence_processor(sz, &from_parent, &to_parent_);
-        };
+        }
 
         to_child
     }.collect::<~[Chan<~[u8]>]>();

src/test/bench/task-perf-jargon-metal-smoke.rs

@@ -28,7 +28,7 @@ fn child_generation(gens_left: uint, c: comm::Chan<()>) {
     // With this code, only as many generations are alive at a time as tasks
     // alive at a time,
     let c = Cell::new(c);
-    do task::spawn_supervised {
+    do spawn {
         let c = c.take();
         if gens_left & 1 == 1 {
             task::deschedule(); // shake things up a bit

src/test/bench/task-perf-linked-failure.rs

@@ -1,4 +1,5 @@
 // xfail-pretty
+// xfail-test linked failure
 
 // Copyright 2012 The Rust Project Developers. See the COPYRIGHT
 // file at the top-level directory of this distribution and at
@@ -35,8 +36,6 @@ fn grandchild_group(num_tasks: uint) {
     for _ in range(0, num_tasks) {
         let ch = ch.clone();
         let mut t = task::task();
-        t.linked();
-        t.unwatched();
         do t.spawn { // linked
             ch.send(());
             let (p, _c) = stream::<()>();

src/test/run-fail/fail-task-name-none.rs

@@ -10,8 +10,11 @@
 
 // error-pattern:task '<unnamed>' failed at 'test'
 
+use std::task;
+
 fn main() {
-    do spawn {
+    do task::try {
         fail!("test");
-    }
+        1
+    }.unwrap()
 }

src/test/run-fail/fail-task-name-owned.rs

@@ -10,10 +10,13 @@
 
 // error-pattern:task 'owned name' failed at 'test'
 
+use std::task;
+
 fn main() {
-    let mut t = ::std::task::task();
+    let mut t = task::task();
     t.name(~"owned name");
-    do t.spawn {
+    do t.try {
         fail!("test");
-    }
+        1
+    }.unwrap()
 }

src/test/run-fail/fail-task-name-send-str.rs

@@ -13,7 +13,8 @@
 fn main() {
     let mut t = ::std::task::task();
     t.name("send name".to_send_str());
-    do t.spawn {
+    do t.try {
         fail!("test");
-    }
+        3
+    }.unwrap()
 }

src/test/run-fail/fail-task-name-static.rs

@@ -13,7 +13,7 @@
 fn main() {
     let mut t = ::std::task::task();
     t.name("static name");
-    do t.spawn {
+    do t.try {
         fail!("test");
-    }
+    }.unwrap()
 }

src/test/run-fail/task-spawn-barefn.rs

@@ -15,7 +15,7 @@ use std::task;
 fn main() {
     // the purpose of this test is to make sure that task::spawn()
     // works when provided with a bare function:
-    task::spawn(startfn);
+    task::try(startfn).unwrap();
 }
 
 fn startfn() {

src/test/run-pass/unwind-box.rs

@@ -18,5 +18,5 @@ fn f() {
 }
 
 pub fn main() {
-    task::spawn_unlinked(f);
+    task::spawn(f);
 }

src/test/run-pass/unwind-resource.rs

@@ -42,7 +42,7 @@ fn f(c: SharedChan<bool>) {
 pub fn main() {
     let (p, c) = stream();
     let c = SharedChan::new(c);
-    task::spawn_unlinked(|| f(c.clone()) );
+    task::spawn(|| f(c.clone()) );
     error!("hiiiiiiiii");
     assert!(p.recv());
 }

src/test/run-pass/unwind-resource2.rs

@@ -35,5 +35,5 @@ fn f() {
 }
 
 pub fn main() {
-    task::spawn_unlinked(f);
+    task::spawn(f);
 }

src/test/run-pass/unwind-unique.rs

@@ -18,5 +18,5 @@ fn f() {
 }
 
 pub fn main() {
-    task::spawn_unlinked(f);
+    task::spawn(f);
 }