auto merge of #8139 : brson/rust/rm-old-task-apis, r=pcwalton

This removes a bunch of options from the task builder interface that are irrelevant to the new scheduler and were generally unused anyway. It also bumps the stack size of new scheduler tasks so that there's enough room to run rustc and changes the interface to `Thread` to not implicitly join threads on destruction, but instead require an explicit, and mandatory, call to `join`.

src/libstd/unstable/mod.rs

@@ -12,7 +12,6 @@
 
 use comm::{GenericChan, GenericPort};
 use comm;
-use libc;
 use prelude::*;
 use task;
 
@@ -37,18 +36,16 @@ The executing thread has no access to a task pointer and will be using
 a normal large stack.
 */
 pub fn run_in_bare_thread(f: ~fn()) {
+    use cell::Cell;
+    use rt::thread::Thread;
+
+    let f_cell = Cell::new(f);
     let (port, chan) = comm::stream();
     // FIXME #4525: Unfortunate that this creates an extra scheduler but it's
-    // necessary since rust_raw_thread_join_delete is blocking
+    // necessary since rust_raw_thread_join is blocking
     do task::spawn_sched(task::SingleThreaded) {
-        unsafe {
-            let closure: &fn() = || {
-                f()
-            };
-            let thread = rust_raw_thread_start(&closure);
-            rust_raw_thread_join_delete(thread);
-            chan.send(());
-        }
+        Thread::start(f_cell.take()).join();
+        chan.send(());
     }
     port.recv();
 }
@@ -70,14 +67,6 @@ fn test_run_in_bare_thread_exchange() {
     }
 }
 
-#[allow(non_camel_case_types)] // runtime type
-pub type raw_thread = libc::c_void;
-
-extern {
-    fn rust_raw_thread_start(f: &(&fn())) -> *raw_thread;
-    fn rust_raw_thread_join_delete(thread: *raw_thread);
-}
-
 
 /// Changes the current working directory to the specified
 /// path while acquiring a global lock, then calls `action`.