diff --git a/src/libextra/comm.rs b/src/libextra/comm.rs
index 09dd85fe0de46..c3b17fe996405 100644
--- a/src/libextra/comm.rs
+++ b/src/libextra/comm.rs
@@ -101,7 +101,7 @@ mod test {
 
     #[test]
     pub fn DuplexStream1() {
-        let (mut left, mut right) = DuplexStream::new();
+        let (left, right) = DuplexStream::new();
 
         left.send(~"abc");
         right.send(123);
@@ -112,10 +112,9 @@ mod test {
 
     #[test]
     pub fn basic_rendezvous_test() {
-        let (mut port, chan) = rendezvous();
+        let (port, chan) = rendezvous();
 
         do spawn {
-            let mut chan = chan;
             chan.send("abc");
         }
 
@@ -126,9 +125,8 @@ mod test {
     fn recv_a_lot() {
         // Rendezvous streams should be able to handle any number of messages being sent
         do run_in_uv_task {
-            let (mut port, chan) = rendezvous();
+            let (port, chan) = rendezvous();
             do spawn {
-                let mut chan = chan;
                 1000000.times(|| { chan.send(()) })
             }
             1000000.times(|| { port.recv() })
@@ -137,9 +135,8 @@ mod test {
 
     #[test]
     fn send_and_fail_and_try_recv() {
-        let (mut port, chan) = rendezvous();
+        let (port, chan) = rendezvous();
         do spawn {
-            let mut chan = chan;
             chan.duplex_stream.send(()); // Can't access this field outside this module
             fail!()
         }
@@ -148,9 +145,8 @@ mod test {
 
     #[test]
     fn try_send_and_recv_then_fail_before_ack() {
-        let (port, mut chan) = rendezvous();
+        let (port, chan) = rendezvous();
         do spawn {
-            let mut port = port;
             port.duplex_stream.recv();
             fail!()
         }
@@ -160,9 +156,8 @@ mod test {
     #[test]
     #[should_fail]
     fn send_and_recv_then_fail_before_ack() {
-        let (port, mut chan) = rendezvous();
+        let (port, chan) = rendezvous();
         do spawn {
-            let mut port = port;
             port.duplex_stream.recv();
             fail!()
         }
diff --git a/src/libstd/c_str.rs b/src/libstd/c_str.rs
index 592efe6d981b1..38deaf2dbcbb8 100644
--- a/src/libstd/c_str.rs
+++ b/src/libstd/c_str.rs
@@ -377,7 +377,6 @@ mod tests {
     use libc;
     use ptr;
     use option::{Some, None};
-    use vec;
 
     #[test]
     fn test_str_multistring_parsing() {
@@ -440,7 +439,7 @@ mod tests {
                 assert_eq!(*ptr::offset(buf, 0), 'f' as libc::c_char);
                 assert_eq!(*ptr::offset(buf, 1), 'o' as libc::c_char);
                 assert_eq!(*ptr::offset(buf, 2), 'o' as libc::c_char);
-                assert_eq!(*ptr::offset(buf, 3), 0xff);
+                assert_eq!(*ptr::offset(buf, 3), 0xff as i8);
                 assert_eq!(*ptr::offset(buf, 4), 0);
             }
         });
diff --git a/src/libstd/io/native/file.rs b/src/libstd/io/native/file.rs
index 74d18f11a1d60..de2655303d606 100644
--- a/src/libstd/io/native/file.rs
+++ b/src/libstd/io/native/file.rs
@@ -907,22 +907,14 @@ pub fn utime(p: &CString, atime: u64, mtime: u64) -> IoResult<()> {
 #[cfg(test)]
 mod tests {
     use io::native::file::{CFile, FileDesc};
-    use io::fs;
     use io;
     use libc;
     use os;
-    use path::Path;
-    use rand;
     use result::Ok;
     use rt::rtio::RtioFileStream;
 
-    fn tmpdir() -> Path {
-        let ret = os::tmpdir().join(format!("rust-{}", rand::random::<u32>()));
-        fs::mkdir(&ret, io::UserRWX);
-        ret
-    }
-
     #[ignore(cfg(target_os = "freebsd"))] // hmm, maybe pipes have a tiny buffer
+    #[test]
     fn test_file_desc() {
         // Run this test with some pipes so we don't have to mess around with
         // opening or closing files.
@@ -949,6 +941,7 @@ mod tests {
     }
 
     #[ignore(cfg(windows))] // apparently windows doesn't like tmpfile
+    #[test]
     fn test_cfile() {
         unsafe {
             let f = libc::tmpfile();
diff --git a/src/libstd/io/util.rs b/src/libstd/io/util.rs
index 75be56113e930..4803054333607 100644
--- a/src/libstd/io/util.rs
+++ b/src/libstd/io/util.rs
@@ -220,7 +220,7 @@ mod test {
     #[test]
     fn test_null_writer() {
         let mut s = NullWriter;
-        let mut buf = ~[0, 0, 0];
+        let buf = ~[0, 0, 0];
         s.write(buf);
         s.flush();
     }
@@ -248,7 +248,7 @@ mod test {
 
         struct TestWriter;
         impl Writer for TestWriter {
-            fn write(&mut self, buf: &[u8]) {
+            fn write(&mut self, _buf: &[u8]) {
                 unsafe { writes += 1 }
             }
 
diff --git a/src/libstd/local_data.rs b/src/libstd/local_data.rs
index 87fe5ac6f220b..ad624f71d0c7a 100644
--- a/src/libstd/local_data.rs
+++ b/src/libstd/local_data.rs
@@ -438,6 +438,9 @@ mod tests {
         static int_key: Key<@int> = &Key;
         do task::spawn {
             set(str_key, @~"string data");
+            set(str_key, @~"string data 2");
+            set(box_key, @@());
+            set(box_key, @@());
             set(int_key, @42);
             // This could cause a segfault if overwriting-destruction is done
             // with the crazy polymorphic transmute rather than the provided
diff --git a/src/libstd/ptr.rs b/src/libstd/ptr.rs
index 070884c078c47..9cf36adc36f23 100644
--- a/src/libstd/ptr.rs
+++ b/src/libstd/ptr.rs
@@ -557,8 +557,6 @@ pub mod ptr_tests {
 
     #[test]
     fn test_ptr_addition() {
-        use vec::raw::*;
-
         unsafe {
             let xs = ~[5, ..16];
             let mut ptr = xs.as_ptr();
diff --git a/src/libstd/rand/rand_impls.rs b/src/libstd/rand/rand_impls.rs
index ff722b739a86a..360f16971acad 100644
--- a/src/libstd/rand/rand_impls.rs
+++ b/src/libstd/rand/rand_impls.rs
@@ -240,12 +240,14 @@ mod tests {
         }
     }
 
+    #[test]
     fn floating_point_edge_cases() {
         // the test for exact equality is correct here.
         assert!(ConstantRng(0xffff_ffff).gen::<f32>() != 1.0)
         assert!(ConstantRng(0xffff_ffff_ffff_ffff).gen::<f64>() != 1.0)
     }
 
+    #[test]
     fn rand_open() {
         // this is unlikely to catch an incorrect implementation that
         // generates exactly 0 or 1, but it keeps it sane.
@@ -260,6 +262,7 @@ mod tests {
         }
     }
 
+    #[test]
     fn rand_closed() {
         let mut rng = task_rng();
         for _ in range(0, 1_000) {
diff --git a/src/libstd/rt/args.rs b/src/libstd/rt/args.rs
index 7b27161ab5d7c..a767af4cc0ebe 100644
--- a/src/libstd/rt/args.rs
+++ b/src/libstd/rt/args.rs
@@ -64,23 +64,25 @@ pub unsafe fn init(argc: int, argv: **u8) { realargs::init(argc, argv) }
 #[cfg(target_os = "freebsd")]
 mod imp {
     use cast;
-    use libc;
+    #[cfg(not(test))] use libc;
     use option::{Option, Some, None};
     use iter::Iterator;
-    use str;
+    #[cfg(not(test))] use str;
     use unstable::finally::Finally;
     use unstable::mutex::{Mutex, MUTEX_INIT};
     use util;
-    use vec;
+    #[cfg(not(test))] use vec;
 
     static mut global_args_ptr: uint = 0;
     static mut lock: Mutex = MUTEX_INIT;
 
+    #[cfg(not(test))]
     pub unsafe fn init(argc: int, argv: **u8) {
         let args = load_argc_and_argv(argc, argv);
         put(args);
     }
 
+    #[cfg(not(test))]
     pub unsafe fn cleanup() {
         rtassert!(take().is_some());
         lock.destroy();
@@ -127,6 +129,7 @@ mod imp {
     }
 
     // Copied from `os`.
+    #[cfg(not(test))]
     unsafe fn load_argc_and_argv(argc: int, argv: **u8) -> ~[~str] {
         vec::from_fn(argc as uint, |i| {
             str::raw::from_c_str(*(argv as **libc::c_char).offset(i as int))
@@ -163,8 +166,8 @@ mod imp {
     }
 }
 
-#[cfg(target_os = "macos")]
-#[cfg(target_os = "win32")]
+#[cfg(target_os = "macos", not(test))]
+#[cfg(target_os = "win32", not(test))]
 mod imp {
     use option::Option;
 
diff --git a/src/libstd/rt/context.rs b/src/libstd/rt/context.rs
index 418557f659b00..31cf069688168 100644
--- a/src/libstd/rt/context.rs
+++ b/src/libstd/rt/context.rs
@@ -395,6 +395,9 @@ pub unsafe fn record_sp_limit(limit: uint) {
 /// As with the setter, this function does not have a __morestack header and can
 /// therefore be called in a "we're out of stack" situation.
 #[inline(always)]
+// currently only called by `rust_stack_exhausted`, which doesn't
+// exist in a test build.
+#[cfg(not(test))]
 pub unsafe fn get_sp_limit() -> uint {
     return target_get_sp_limit();
 
diff --git a/src/libstd/rt/sched.rs b/src/libstd/rt/sched.rs
index cd21cdeb711b7..15aa1602cd0e0 100644
--- a/src/libstd/rt/sched.rs
+++ b/src/libstd/rt/sched.rs
@@ -1341,6 +1341,8 @@ mod test {
     }
 
     // FIXME: #9407: xfail-test
+    #[ignore]
+    #[test]
     fn dont_starve_1() {
         stress_factor().times(|| {
             do run_in_mt_newsched_task {
diff --git a/src/libstd/rt/task.rs b/src/libstd/rt/task.rs
index 62e012f9f4120..3299caa089aba 100644
--- a/src/libstd/rt/task.rs
+++ b/src/libstd/rt/task.rs
@@ -26,7 +26,6 @@ use local_data;
 use option::{Option, Some, None};
 use rt::borrowck::BorrowRecord;
 use rt::borrowck;
-use rt::context;
 use rt::context::Context;
 use rt::env;
 use rt::kill::Death;
@@ -511,6 +510,7 @@ impl Unwinder {
                   //   irrelevant for documentation purposes.
 #[cfg(not(test))] // in testing, use the original libstd's version
 pub extern "C" fn rust_stack_exhausted() {
+    use rt::context;
     use rt::in_green_task_context;
     use rt::task::Task;
     use rt::local::Local;
diff --git a/src/libstd/run.rs b/src/libstd/run.rs
index 85b57fdbc351c..d92291bbfbd06 100644
--- a/src/libstd/run.rs
+++ b/src/libstd/run.rs
@@ -339,7 +339,7 @@ mod tests {
     use task::spawn;
     use unstable::running_on_valgrind;
     use io::native::file;
-    use io::{FileNotFound, OtherIoError, Reader, Writer, io_error};
+    use io::{FileNotFound, Reader, Writer, io_error};
 
     #[test]
     #[cfg(not(target_os="android"))] // FIXME(#10380)
diff --git a/src/libstd/str.rs b/src/libstd/str.rs
index 7225a1ab6cbe5..5f98a34520c09 100644
--- a/src/libstd/str.rs
+++ b/src/libstd/str.rs
@@ -2734,7 +2734,6 @@ mod tests {
     use option::{None, Some, Option};
     use ptr;
     use str::*;
-    use vec;
     use vec::{Vector, ImmutableVector, CopyableVector};
     use cmp::{TotalOrd, Less, Equal, Greater};
     use send_str::{SendStrOwned, SendStrStatic};
diff --git a/src/libstd/task/mod.rs b/src/libstd/task/mod.rs
index 0e56f42f5b9c0..3310dddc3276a 100644
--- a/src/libstd/task/mod.rs
+++ b/src/libstd/task/mod.rs
@@ -437,9 +437,6 @@ pub fn failing() -> bool {
 // !!! These tests are dangerous. If Something is buggy, they will hang, !!!
 // !!! instead of exiting cleanly. This might wedge the buildbots.       !!!
 
-#[cfg(test)]
-fn block_forever() { let (po, _ch) = Chan::<()>::new(); po.recv(); }
-
 #[test]
 fn test_unnamed_task() {
     use rt::test::run_in_uv_task;
@@ -507,11 +504,6 @@ fn test_run_basic() {
     po.recv();
 }
 
-#[cfg(test)]
-struct Wrapper {
-    f: Option<Chan<()>>
-}
-
 #[test]
 fn test_add_wrapper() {
     let (po, ch) = Chan::new();
diff --git a/src/libstd/vec.rs b/src/libstd/vec.rs
index ad0d8861ee9c4..3fa41711d2b0a 100644
--- a/src/libstd/vec.rs
+++ b/src/libstd/vec.rs
@@ -2678,7 +2678,7 @@ impl<A> Extendable<A> for ~[A] {
 
 #[cfg(test)]
 mod tests {
-    use option::{None, Option, Some};
+    use option::{None, Some};
     use mem;
     use vec::*;
     use cmp::*;
@@ -2688,22 +2688,8 @@ mod tests {
 
     fn square_ref(n: &uint) -> uint { square(*n) }
 
-    fn is_three(n: &uint) -> bool { *n == 3u }
-
     fn is_odd(n: &uint) -> bool { *n % 2u == 1u }
 
-    fn is_equal(x: &uint, y:&uint) -> bool { *x == *y }
-
-    fn square_if_odd_r(n: &uint) -> Option<uint> {
-        if *n % 2u == 1u { Some(*n * *n) } else { None }
-    }
-
-    fn square_if_odd_v(n: uint) -> Option<uint> {
-        if n % 2u == 1u { Some(n * n) } else { None }
-    }
-
-    fn add(x: uint, y: &uint) -> uint { x + *y }
-
     #[test]
     fn test_unsafe_ptrs() {
         unsafe {
@@ -2982,6 +2968,7 @@ mod tests {
         assert_eq!(g, None);
     }
 
+    #[test]
     fn test_swap_remove() {
         let mut v = ~[1, 2, 3, 4, 5];
         let mut e = v.swap_remove(0);