libcore: Fix tests.

src/libcore/comm.rs

@@ -596,9 +596,10 @@ mod test {
 
         c1.send(~"abc");
 
-        match (p1, p2).select() {
+        let mut tuple = (p1, p2);
-          Right(_) => fail!(),
+        match tuple.select() {
-          _ => ()
+            Right(_) => fail!(),
+            _ => (),
         }
 
         c2.send(123);

src/libcore/flate.rs

@@ -84,10 +84,11 @@ pub fn inflate_bytes(bytes: &const [u8]) -> ~[u8] {
 #[test]
 #[allow(non_implicitly_copyable_typarams)]
 fn test_flate_round_trip() {
-    let r = rand::rng();
+    let mut r = rand::rng();
     let mut words = ~[];
     for 20.times {
-        words.push(r.gen_bytes(r.gen_uint_range(1, 10)));
+        let range = r.gen_uint_range(1, 10);
+        words.push(r.gen_bytes(range));
     }
     for 20.times {
         let mut in = ~[];

src/libcore/hash.rs

@@ -473,10 +473,10 @@ mod tests {
         let k1 = 0x_0f_0e_0d_0c_0b_0a_09_08_u64;
         let mut buf : ~[u8] = ~[];
         let mut t = 0;
-        let stream_inc = &State(k0,k1);
+        let mut stream_inc = SipState::new(k0, k1);
-        let stream_full = &State(k0,k1);
+        let mut stream_full = SipState::new(k0, k1);
 
-        fn to_hex_str(r:  &[u8, ..8]) -> ~str {
+        fn to_hex_str(r: &[u8, ..8]) -> ~str {
             let mut s = ~"";
             for vec::each(*r) |b| {
                 s += uint::to_str_radix(*b as uint, 16u);

src/libcore/io.rs

@@ -1886,15 +1886,15 @@ mod tests {
     fn bytes_buffer_overwrite() {
         let wr = BytesWriter();
         wr.write(~[0u8, 1u8, 2u8, 3u8]);
-        assert!(wr.bytes == ~[0u8, 1u8, 2u8, 3u8]);
+        assert!(*wr.bytes == ~[0u8, 1u8, 2u8, 3u8]);
         wr.seek(-2, SeekCur);
         wr.write(~[4u8, 5u8, 6u8, 7u8]);
-        assert!(wr.bytes == ~[0u8, 1u8, 4u8, 5u8, 6u8, 7u8]);
+        assert!(*wr.bytes == ~[0u8, 1u8, 4u8, 5u8, 6u8, 7u8]);
         wr.seek(-2, SeekEnd);
         wr.write(~[8u8]);
         wr.seek(1, SeekSet);
         wr.write(~[9u8]);
-        assert!(wr.bytes == ~[0u8, 9u8, 4u8, 5u8, 8u8, 7u8]);
+        assert!(*wr.bytes == ~[0u8, 9u8, 4u8, 5u8, 8u8, 7u8]);
     }
 
     #[test]

src/libcore/os.rs

@@ -1435,7 +1435,7 @@ mod tests {
     }
 
     fn make_rand_name() -> ~str {
-        let rng = rand::rng();
+        let mut rng = rand::rng();
         let n = ~"TEST" + rng.gen_str(10u);
         assert!(getenv(n).is_none());
         n

src/libcore/pipes.rs

@@ -894,9 +894,10 @@ mod test {
 
         c1.send(~"abc");
 
-        match (p1, p2).select() {
+        let mut tuple = (p1, p2);
-          Right(_) => fail!(),
+        match tuple.select() {
-          _ => ()
+            Right(_) => fail!(),
+            _ => (),
         }
 
         c2.send(123);

src/libcore/rand.rs

@@ -879,8 +879,8 @@ mod tests {
     #[test]
     fn test_rng_seeded() {
         let seed = seed();
-        let ra = IsaacRng::new_seeded(seed);
+        let mut ra = IsaacRng::new_seeded(seed);
-        let rb = IsaacRng::new_seeded(seed);
+        let mut rb = IsaacRng::new_seeded(seed);
         assert!(ra.gen_str(100u) == rb.gen_str(100u));
     }
 
@@ -888,15 +888,15 @@ mod tests {
     fn test_rng_seeded_custom_seed() {
         // much shorter than generated seeds which are 1024 bytes
         let seed = [2u8, 32u8, 4u8, 32u8, 51u8];
-        let ra = IsaacRng::new_seeded(seed);
+        let mut ra = IsaacRng::new_seeded(seed);
-        let rb = IsaacRng::new_seeded(seed);
+        let mut rb = IsaacRng::new_seeded(seed);
         assert!(ra.gen_str(100u) == rb.gen_str(100u));
     }
 
     #[test]
     fn test_rng_seeded_custom_seed2() {
         let seed = [2u8, 32u8, 4u8, 32u8, 51u8];
-        let ra = IsaacRng::new_seeded(seed);
+        let mut ra = IsaacRng::new_seeded(seed);
         // Regression test that isaac is actually using the above vector
         let r = ra.next();
         error!("%?", r);
@@ -906,7 +906,7 @@ mod tests {
 
     #[test]
     fn test_gen_int_range() {
-        let r = rng();
+        let mut r = rng();
         let a = r.gen_int_range(-3, 42);
         assert!(a >= -3 && a < 42);
         assert!(r.gen_int_range(0, 1) == 0);
@@ -917,12 +917,13 @@ mod tests {
     #[should_fail]
     #[ignore(cfg(windows))]
     fn test_gen_int_from_fail() {
-        rng().gen_int_range(5, -2);
+        let mut r = rng();
+        r.gen_int_range(5, -2);
     }
 
     #[test]
     fn test_gen_uint_range() {
-        let r = rng();
+        let mut r = rng();
         let a = r.gen_uint_range(3u, 42u);
         assert!(a >= 3u && a < 42u);
         assert!(r.gen_uint_range(0u, 1u) == 0u);
@@ -933,12 +934,13 @@ mod tests {
     #[should_fail]
     #[ignore(cfg(windows))]
     fn test_gen_uint_range_fail() {
-        rng().gen_uint_range(5u, 2u);
+        let mut r = rng();
+        r.gen_uint_range(5u, 2u);
     }
 
     #[test]
     fn test_gen_float() {
-        let r = rng();
+        let mut r = rng();
         let a = r.gen::<float>();
         let b = r.gen::<float>();
         debug!((a, b));
@@ -946,14 +948,14 @@ mod tests {
 
     #[test]
     fn test_gen_weighted_bool() {
-        let r = rng();
+        let mut r = rng();
         assert!(r.gen_weighted_bool(0u) == true);
         assert!(r.gen_weighted_bool(1u) == true);
     }
 
     #[test]
     fn test_gen_str() {
-        let r = rng();
+        let mut r = rng();
         debug!(r.gen_str(10u));
         debug!(r.gen_str(10u));
         debug!(r.gen_str(10u));
@@ -964,7 +966,7 @@ mod tests {
 
     #[test]
     fn test_gen_bytes() {
-        let r = rng();
+        let mut r = rng();
         assert!(r.gen_bytes(0u).len() == 0u);
         assert!(r.gen_bytes(10u).len() == 10u);
         assert!(r.gen_bytes(16u).len() == 16u);
@@ -972,13 +974,13 @@ mod tests {
 
     #[test]
     fn test_choose() {
-        let r = rng();
+        let mut r = rng();
         assert!(r.choose([1, 1, 1]) == 1);
     }
 
     #[test]
     fn test_choose_option() {
-        let r = rng();
+        let mut r = rng();
         let x: Option<int> = r.choose_option([]);
         assert!(x.is_none());
         assert!(r.choose_option([1, 1, 1]) == Some(1));
@@ -986,7 +988,7 @@ mod tests {
 
     #[test]
     fn test_choose_weighted() {
-        let r = rng();
+        let mut r = rng();
         assert!(r.choose_weighted(~[
             Weighted { weight: 1u, item: 42 },
         ]) == 42);
@@ -998,7 +1000,7 @@ mod tests {
 
     #[test]
     fn test_choose_weighted_option() {
-        let r = rng();
+        let mut r = rng();
         assert!(r.choose_weighted_option(~[
             Weighted { weight: 1u, item: 42 },
         ]) == Some(42));
@@ -1012,7 +1014,7 @@ mod tests {
 
     #[test]
     fn test_weighted_vec() {
-        let r = rng();
+        let mut r = rng();
         let empty: ~[int] = ~[];
         assert!(r.weighted_vec(~[]) == empty);
         assert!(r.weighted_vec(~[
@@ -1024,7 +1026,7 @@ mod tests {
 
     #[test]
     fn test_shuffle() {
-        let r = rng();
+        let mut r = rng();
         let empty: ~[int] = ~[];
         assert!(r.shuffle(~[]) == empty);
         assert!(r.shuffle(~[1, 1, 1]) == ~[1, 1, 1]);
@@ -1032,7 +1034,7 @@ mod tests {
 
     #[test]
     fn test_task_rng() {
-        let r = task_rng();
+        let mut r = task_rng();
         r.gen::<int>();
         assert!(r.shuffle(~[1, 1, 1]) == ~[1, 1, 1]);
         assert!(r.gen_uint_range(0u, 1u) == 0u);
@@ -1079,7 +1081,7 @@ mod tests {
                 let rt_rng = do vec::as_imm_buf(seed) |p, sz| {
                     rustrt::rand_new_seeded(p, sz as size_t)
                 };
-                let rng = IsaacRng::new_seeded(seed);
+                let mut rng = IsaacRng::new_seeded(seed);
 
                 for 10000.times {
                     assert_eq!(rng.next(), rustrt::rand_next(rt_rng));

src/libcore/task/mod.rs

@@ -597,12 +597,13 @@ pub unsafe fn atomically<U>(f: &fn() -> U) -> U {
 
 #[test] #[should_fail] #[ignore(cfg(windows))]
 fn test_cant_dup_task_builder() {
-    let b = task().unlinked();
+    let mut builder = task();
-    do b.spawn { }
+    builder.unlinked();
+    do builder.spawn {}
     // FIXME(#3724): For now, this is a -runtime- failure, because we haven't
     // got move mode on self. When 3724 is fixed, this test should fail to
     // compile instead, and should go in tests/compile-fail.
-    do b.spawn { } // b should have been consumed by the previous call
+    do builder.spawn {} // b should have been consumed by the previous call
 }
 
 // The following 8 tests test the following 2^3 combinations:
@@ -645,43 +646,31 @@ fn test_spawn_unlinked_sup_fail_down() {
 #[test] #[should_fail] #[ignore(cfg(windows))]
 fn test_spawn_linked_sup_fail_up() { // child fails; parent fails
     let (po, _ch) = stream::<()>();
+
     // Unidirectional "parenting" shouldn't override bidirectional linked.
     // We have to cheat with opts - the interface doesn't support them because
     // they don't make sense (redundant with task().supervised()).
-    let opts = {
+    let mut b0 = task();
-        let mut opts = default_task_opts();
+    b0.opts.linked = true;
-        opts.linked = true;
+    b0.opts.supervised = true;
-        opts.supervised = true;
-        opts
-    };
 
-    let b0 = task();
+    do b0.spawn {
-    let b1 = TaskBuilder {
+        fail!();
-        opts: opts,
+    }
-        can_not_copy: None,
-        .. b0
-    };
-    do b1.spawn { fail!(); }
     po.recv(); // We should get punted awake
 }
 #[test] #[should_fail] #[ignore(cfg(windows))]
 fn test_spawn_linked_sup_fail_down() { // parent fails; child fails
     // We have to cheat with opts - the interface doesn't support them because
     // they don't make sense (redundant with task().supervised()).
-    let opts = {
+    let mut b0 = task();
-        let mut opts = default_task_opts();
+    b0.opts.linked = true;
-        opts.linked = true;
+    b0.opts.supervised = true;
-        opts.supervised = true;
+    do b0.spawn {
-        opts
+        loop {
-    };
+            task::yield();
-
+        }
-    let b0 = task();
+    }
-    let b1 = TaskBuilder {
-        opts: opts,
-        can_not_copy: None,
-        .. b0
-    };
-    do b1.spawn { loop { task::yield(); } }
     fail!(); // *both* mechanisms would be wrong if this didn't kill the child
 }
 #[test] #[should_fail] #[ignore(cfg(windows))]
@@ -700,7 +689,13 @@ fn test_spawn_linked_unsup_fail_down() { // parent fails; child fails
 #[test] #[should_fail] #[ignore(cfg(windows))]
 fn test_spawn_linked_unsup_default_opts() { // parent fails; child fails
     // Make sure the above test is the same as this one.
-    do task().linked().spawn { loop { task::yield(); } }
+    let mut builder = task();
+    builder.linked();
+    do builder.spawn {
+        loop {
+            task::yield();
+        }
+    }
     fail!();
 }
 
@@ -758,7 +753,8 @@ fn test_spawn_linked_sup_propagate_sibling() {
 #[test]
 fn test_run_basic() {
     let (po, ch) = stream::<()>();
-    do task().spawn {
+    let mut builder = task();
+    do builder.spawn {
         ch.send(());
     }
     po.recv();
@@ -772,18 +768,18 @@ struct Wrapper {
 #[test]
 fn test_add_wrapper() {
     let (po, ch) = stream::<()>();
-    let b0 = task();
+    let mut b0 = task();
-    let ch = Wrapper { f: Some(ch) };
+    let ch = Cell(ch);
-    let b1 = do b0.add_wrapper |body| {
+    do b0.add_wrapper |body| {
-        let ch = Wrapper { f: Some(ch.f.swap_unwrap()) };
+        let ch = Cell(ch.take());
         let result: ~fn() = || {
-            let ch = ch.f.swap_unwrap();
+            let mut ch = ch.take();
             body();
             ch.send(());
         };
         result
     };
-    do b1.spawn { }
+    do b0.spawn { }
     po.recv();
 }
 
@@ -791,12 +787,16 @@ fn test_add_wrapper() {
 #[ignore(cfg(windows))]
 fn test_future_result() {
     let mut result = None;
-    do task().future_result(|r| { result = Some(r); }).spawn { }
+    let mut builder = task();
+    builder.future_result(|r| result = Some(r));
+    do builder.spawn {}
     assert!(result.unwrap().recv() == Success);
 
     result = None;
-    do task().future_result(|r|
+    let mut builder = task();
-        { result = Some(r); }).unlinked().spawn {
+    builder.future_result(|r| result = Some(r));
+    builder.unlinked();
+    do builder.spawn {
         fail!();
     }
     assert!(result.unwrap().recv() == Failure);
@@ -804,7 +804,9 @@ fn test_future_result() {
 
 #[test] #[should_fail] #[ignore(cfg(windows))]
 fn test_back_to_the_future_result() {
-    let _ = task().future_result(util::ignore).future_result(util::ignore);
+    let mut builder = task();
+    builder.future_result(util::ignore);
+    builder.future_result(util::ignore);
 }
 
 #[test]
@@ -866,12 +868,12 @@ fn test_spawn_sched_childs_on_default_sched() {
     // Assuming tests run on the default scheduler
     let default_id = unsafe { rt::rust_get_sched_id() };
 
-    let ch = Wrapper { f: Some(ch) };
+    let ch = Cell(ch);
     do spawn_sched(SingleThreaded) {
         let parent_sched_id = unsafe { rt::rust_get_sched_id() };
-        let ch = Wrapper { f: Some(ch.f.swap_unwrap()) };
+        let ch = Cell(ch.take());
         do spawn {
-            let ch = ch.f.swap_unwrap();
+            let ch = ch.take();
             let child_sched_id = unsafe { rt::rust_get_sched_id() };
             assert!(parent_sched_id != child_sched_id);
             assert!(child_sched_id == default_id);
@@ -979,7 +981,8 @@ fn test_avoid_copying_the_body_spawn() {
 #[test]
 fn test_avoid_copying_the_body_task_spawn() {
     do avoid_copying_the_body |f| {
-        do task().spawn || {
+        let mut builder = task();
+        do builder.spawn || {
             f();
         }
     }
@@ -1006,7 +1009,9 @@ fn test_avoid_copying_the_body_unlinked() {
 #[test]
 fn test_platform_thread() {
     let (po, ch) = stream();
-    do task().sched_mode(PlatformThread).spawn {
+    let mut builder = task();
+    builder.sched_mode(PlatformThread);
+    do builder.spawn {
         ch.send(());
     }
     po.recv();

src/libcore/unstable/weak_task.rs

@@ -191,12 +191,14 @@ fn test_select_stream_and_oneshot() {
     use comm::select2i;
     use either::{Left, Right};
 
-    let (port, chan) = stream();
+    let mut (port, chan) = stream();
+    let port = Cell(port);
     let (waitport, waitchan) = stream();
     do spawn {
         unsafe {
-            do weaken_task |signal| {
+            do weaken_task |mut signal| {
-                match select2i(&port, &signal) {
+                let mut port = port.take();
+                match select2i(&mut port, &mut signal) {
                     Left(*) => (),
                     Right(*) => fail!()
                 }

src/librustc/middle/astencode.rs

@@ -1237,7 +1237,7 @@ fn test_simplification() {
     let ext_cx = mk_ctxt();
     let item_in = ast::ii_item(quote_item!(
         fn new_int_alist<B:Copy>() -> alist<int, B> {
-            fn eq_int(&&a: int, &&b: int) -> bool { a == b }
+            fn eq_int(a: int, b: int) -> bool { a == b }
             return alist {eq_fn: eq_int, data: ~[]};
         }
     ).get());

src/libstd/arc.rs

@@ -673,7 +673,9 @@ mod tests {
         let mut children = ~[];
         for 5.times {
             let arc3 = (*arc).clone();
-            do task::task().future_result(|r| children.push(r)).spawn {
+            let mut builder = task::task();
+            builder.future_result(|r| children.push(r));
+            do builder.spawn {
                 do arc3.read |num| {
                     assert!(*num >= 0);
                 }
@@ -681,11 +683,15 @@ mod tests {
         }
 
         // Wait for children to pass their asserts
-        for vec::each(children) |r| { r.recv(); }
+        for vec::each(children) |r| {
+            r.recv();
+        }
 
         // Wait for writer to finish
         p.recv();
-        do arc.read |num| { assert!(*num == 10); }
+        do arc.read |num| {
+            assert!(*num == 10);
+        }
     }
     #[test]
     fn test_rw_downgrade() {

src/libstd/bitv.rs

@@ -1426,7 +1426,7 @@ mod tests {
 
     #[bench]
     fn bench_uint_small(b: &mut BenchHarness) {
-        let r = rng();
+        let mut r = rng();
         let mut bitv = 0 as uint;
         do b.iter {
             bitv |= (1 << ((r.next() as uint) % uint::bits));
@@ -1435,7 +1435,7 @@ mod tests {
 
     #[bench]
     fn bench_small_bitv_small(b: &mut BenchHarness) {
-        let r = rng();
+        let mut r = rng();
         let mut bitv = SmallBitv::new(uint::bits);
         do b.iter {
             bitv.set((r.next() as uint) % uint::bits, true);
@@ -1444,7 +1444,7 @@ mod tests {
 
     #[bench]
     fn bench_big_bitv_small(b: &mut BenchHarness) {
-        let r = rng();
+        let mut r = rng();
         let mut bitv = BigBitv::new(~[0]);
         do b.iter {
             bitv.set((r.next() as uint) % uint::bits, true);
@@ -1453,7 +1453,7 @@ mod tests {
 
     #[bench]
     fn bench_big_bitv_big(b: &mut BenchHarness) {
-        let r = rng();
+        let mut r = rng();
         let mut storage = ~[];
         storage.grow(bench_bits / uint::bits, &0);
         let mut bitv = BigBitv::new(storage);
@@ -1464,7 +1464,7 @@ mod tests {
 
     #[bench]
     fn bench_bitv_big(b: &mut BenchHarness) {
-        let r = rng();
+        let mut r = rng();
         let mut bitv = Bitv::new(bench_bits, false);
         do b.iter {
             bitv.set((r.next() as uint) % bench_bits, true);
@@ -1473,7 +1473,7 @@ mod tests {
 
     #[bench]
     fn bench_bitv_small(b: &mut BenchHarness) {
-        let r = rng();
+        let mut r = rng();
         let mut bitv = Bitv::new(uint::bits, false);
         do b.iter {
             bitv.set((r.next() as uint) % uint::bits, true);
@@ -1482,7 +1482,7 @@ mod tests {
 
     #[bench]
     fn bench_bitv_set_small(b: &mut BenchHarness) {
-        let r = rng();
+        let mut r = rng();
         let mut bitv = BitvSet::new();
         do b.iter {
             bitv.insert((r.next() as uint) % uint::bits);
@@ -1491,7 +1491,7 @@ mod tests {
 
     #[bench]
     fn bench_bitv_set_big(b: &mut BenchHarness) {
-        let r = rng();
+        let mut r = rng();
         let mut bitv = BitvSet::new();
         do b.iter {
             bitv.insert((r.next() as uint) % bench_bits);

src/libstd/flatpipes.rs

@@ -645,7 +645,7 @@ mod test {
 
         chan.send(10);
 
-        let bytes = copy chan.byte_chan.writer.bytes;
+        let bytes = copy *chan.byte_chan.writer.bytes;
 
         let reader = BufReader::new(bytes);
         let port = serial::reader_port(reader);
@@ -692,7 +692,7 @@ mod test {
 
         chan.send(10);
 
-        let bytes = copy chan.byte_chan.writer.bytes;
+        let bytes = copy *chan.byte_chan.writer.bytes;
 
         let reader = BufReader::new(bytes);
         let port = pod::reader_port(reader);

src/libstd/future.rs

@@ -184,9 +184,9 @@ pub fn spawn<A:Owned>(blk: ~fn() -> A) -> Future<A> {
 #[allow(non_implicitly_copyable_typarams)]
 #[cfg(test)]
 mod test {
-
     use future::*;
 
+    use core::cell::Cell;
     use core::comm::{oneshot, send_one};
     use core::task;
 
@@ -239,8 +239,9 @@ mod test {
     #[test]
     fn test_sendable_future() {
         let expected = ~"schlorf";
-        let mut f = do spawn { copy expected };
+        let f = Cell(do spawn { copy expected });
-        do task::spawn || {
+        do task::spawn {
+            let mut f = f.take();
             let actual = f.get();
             assert!(actual == expected);
         }

src/libstd/net_tcp.rs

@@ -1963,7 +1963,7 @@ mod test {
     }
 
     fn tcp_write_single(sock: &TcpSocket, val: ~[u8]) {
-        let write_result_future = sock.write_future(val);
+        let mut write_result_future = sock.write_future(val);
         let write_result = write_result_future.get();
         if result::is_err(&write_result) {
             debug!("tcp_write_single: write failed!");

src/libstd/sort.rs

@@ -946,8 +946,10 @@ mod test_tim_sort {
 
     impl Ord for CVal {
         fn lt(&self, other: &CVal) -> bool {
-            let rng = rand::rng();
+            let mut rng = rand::rng();
-            if rng.gen::<float>() > 0.995 { fail!(~"It's happening!!!"); }
+            if rng.gen::<float>() > 0.995 {
+                fail!(~"It's happening!!!");
+            }
             (*self).val < other.val
         }
         fn le(&self, other: &CVal) -> bool { (*self).val <= other.val }
@@ -995,7 +997,7 @@ mod test_tim_sort {
     #[should_fail]
     #[cfg(unix)]
     fn crash_test() {
-        let rng = rand::rng();
+        let mut rng = rand::rng();
         let mut arr = do vec::from_fn(1000) |_i| {
             CVal { val: rng.gen() }
         };
@@ -1015,7 +1017,7 @@ mod test_tim_sort {
 
     #[test]
     fn test_bad_Ord_impl() {
-        let rng = rand::rng();
+        let mut rng = rand::rng();
         let mut arr = do vec::from_fn(500) |_i| {
             DVal { val: rng.gen() }
         };
@@ -1067,7 +1069,7 @@ mod big_tests {
             }
         }
 
-        let rng = rand::rng();
+        let mut rng = rand::rng();
 
         for uint::range(lo, hi) |i| {
             let n = 1 << i;
@@ -1138,7 +1140,7 @@ mod big_tests {
             }
         }
 
-        let rng = rand::rng();
+        let mut rng = rand::rng();
 
         for uint::range(lo, hi) |i| {
             let n = 1 << i;

src/libstd/timer.rs

@@ -219,7 +219,7 @@ mod test {
                 let hl_loop_clone = hl_loop.clone();
                 do task::spawn {
                     use core::rand::*;
-                    let rng = rng();
+                    let mut rng = rng();
                     for old_iter::repeat(times) {
                         sleep(&hl_loop_clone, rng.next() as uint % maxms);
                     }
@@ -276,7 +276,8 @@ mod test {
         let hl_loop = uv::global_loop::get();
 
         for old_iter::repeat(times as uint) {
-            let expected = rand::rng().gen_str(16u);
+            let mut rng = rand::rng();
+            let expected = rng.gen_str(16u);
             let (test_po, test_ch) = stream::<~str>();
             let hl_loop_clone = hl_loop.clone();
             do task::spawn() {

src/libstd/treemap.rs

@@ -848,7 +848,7 @@ mod test_treemap {
         check_equal(ctrl, &map);
         assert!(map.find(&5).is_none());
 
-        let rng = rand::IsaacRng::new_seeded(&[42]);
+        let mut rng = rand::IsaacRng::new_seeded(&[42]);
 
         for 3.times {
             for 90.times {