diff --git a/src/libextra/bitv.rs b/src/libextra/bitv.rs
index 672a61b1ad8..0891d230810 100644
--- a/src/libextra/bitv.rs
+++ b/src/libextra/bitv.rs
@@ -1,4 +1,4 @@
-// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
+// Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
 // file at the top-level directory of this distribution and at
 // http://rust-lang.org/COPYRIGHT.
 //
@@ -13,7 +13,6 @@
 use core::cmp;
 use core::ops;
 use core::uint;
-use core::vec::from_elem;
 use core::vec;
 
 struct SmallBitv {
diff --git a/src/libextra/test.rs b/src/libextra/test.rs
index 59c6a12e036..ddc8eb4430d 100644
--- a/src/libextra/test.rs
+++ b/src/libextra/test.rs
@@ -1,4 +1,4 @@
-// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
+// Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
 // file at the top-level directory of this distribution and at
 // http://rust-lang.org/COPYRIGHT.
 //
@@ -24,13 +24,11 @@
 use core::comm::{stream, SharedChan};
 use core::either;
 use core::io;
-use core::num;
 use core::option;
 use core::result;
 use core::str;
 use core::task;
 use core::to_str::ToStr;
-use core::u64;
 use core::uint;
 use core::vec;
 
diff --git a/src/libextra/uv_global_loop.rs b/src/libextra/uv_global_loop.rs
index 8752f675a8d..286863bef64 100644
--- a/src/libextra/uv_global_loop.rs
+++ b/src/libextra/uv_global_loop.rs
@@ -1,4 +1,4 @@
-// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
+// Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
 // file at the top-level directory of this distribution and at
 // http://rust-lang.org/COPYRIGHT.
 //
@@ -16,9 +16,7 @@
 use uv_iotask::{IoTask, spawn_iotask};
 
 use core::comm::Chan;
-use core::libc;
 use core::option::{Some, None};
-use core::str;
 use core::task::task;
 use core::unstable::global::{global_data_clone_create, global_data_clone};
 use core::unstable::weak_task::weaken_task;
diff --git a/src/librustc/back/link.rs b/src/librustc/back/link.rs
index 02c0b19e565..0695b88bb7f 100644
--- a/src/librustc/back/link.rs
+++ b/src/librustc/back/link.rs
@@ -1,4 +1,4 @@
-// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
+// Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
 // file at the top-level directory of this distribution and at
 // http://rust-lang.org/COPYRIGHT.
 //
@@ -106,9 +106,7 @@ pub mod jit {
     use metadata::cstore;
 
     use core::cast;
-    use core::char;
     use core::libc::c_int;
-    use core::os;
     use core::ptr;
     use core::str;
 
diff --git a/src/librustc/back/passes.rs b/src/librustc/back/passes.rs
index cc9fe577159..ffa551b21ba 100644
--- a/src/librustc/back/passes.rs
+++ b/src/librustc/back/passes.rs
@@ -1,4 +1,4 @@
-// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
+// Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
 // file at the top-level directory of this distribution and at
 // http://rust-lang.org/COPYRIGHT.
 //
@@ -12,7 +12,7 @@
 use core::str;
 use core::io;
 
-use driver::session::{OptLevel, No, Less, Default, Aggressive};
+use driver::session::{OptLevel, No, Less, Aggressive};
 use driver::session::{Session};
 use lib::llvm::{PassRef, ModuleRef,PassManagerRef,TargetDataRef};
 use lib::llvm::llvm;
diff --git a/src/librustc/middle/trans/foreign.rs b/src/librustc/middle/trans/foreign.rs
index a7a8cd088d2..196b4e5338f 100644
--- a/src/librustc/middle/trans/foreign.rs
+++ b/src/librustc/middle/trans/foreign.rs
@@ -34,7 +34,6 @@
 use middle::ty::FnSig;
 use util::ppaux::ty_to_str;
 
-use core::str;
 use core::uint;
 use core::vec;
 use syntax::codemap::span;
diff --git a/src/librustc/middle/trans/glue.rs b/src/librustc/middle/trans/glue.rs
index 013a40c95c5..e2f7dc086d0 100644
--- a/src/librustc/middle/trans/glue.rs
+++ b/src/librustc/middle/trans/glue.rs
@@ -1,4 +1,4 @@
-// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
+// Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
 // file at the top-level directory of this distribution and at
 // http://rust-lang.org/COPYRIGHT.
 //
@@ -19,7 +19,6 @@
 use driver::session;
 use lib;
 use lib::llvm::{llvm, ValueRef, TypeRef, True};
-use lib::llvm::type_to_str;
 use middle::trans::adt;
 use middle::trans::base::*;
 use middle::trans::callee;
diff --git a/src/librustc/middle/ty.rs b/src/librustc/middle/ty.rs
index 8815259b3cc..108ea333e1a 100644
--- a/src/librustc/middle/ty.rs
+++ b/src/librustc/middle/ty.rs
@@ -37,7 +37,6 @@
 use core::u32;
 use core::uint;
 use core::vec;
-use extra::smallintmap::SmallIntMap;
 use syntax::ast::*;
 use syntax::ast_util::is_local;
 use syntax::ast_util;
diff --git a/src/librustdoc/astsrv.rs b/src/librustdoc/astsrv.rs
index 23810748b43..ae7968a4d46 100644
--- a/src/librustdoc/astsrv.rs
+++ b/src/librustdoc/astsrv.rs
@@ -1,4 +1,4 @@
-// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
+// Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
 // file at the top-level directory of this distribution and at
 // http://rust-lang.org/COPYRIGHT.
 //
@@ -24,7 +24,6 @@
 use core::cell::Cell;
 use core::comm::{stream, SharedChan, Port};
 use core::task;
-use core::vec;
 use rustc::driver::driver;
 use rustc::driver::session::Session;
 use rustc::driver::session::{basic_options, options};
@@ -33,6 +32,8 @@
 use syntax::ast_map;
 use syntax;
 
+#[cfg(test)] use core::vec;
+
 pub struct Ctxt {
     ast: @ast::crate,
     ast_map: ast_map::map
diff --git a/src/librustdoc/extract.rs b/src/librustdoc/extract.rs
index 3303a79d1b2..920a72077f0 100644
--- a/src/librustdoc/extract.rs
+++ b/src/librustdoc/extract.rs
@@ -1,4 +1,4 @@
-// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
+// Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
 // file at the top-level directory of this distribution and at
 // http://rust-lang.org/COPYRIGHT.
 //
@@ -16,7 +16,6 @@
 use doc::ItemUtils;
 use doc;
 
-use core::local_data::local_data_get;
 use core::vec;
 use syntax::ast;
 use syntax::parse::token::{ident_interner};
diff --git a/src/librustdoc/markdown_writer.rs b/src/librustdoc/markdown_writer.rs
index 86b51dfabf0..7bcfa1acdfa 100644
--- a/src/librustdoc/markdown_writer.rs
+++ b/src/librustdoc/markdown_writer.rs
@@ -1,4 +1,4 @@
-// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
+// Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
 // file at the top-level directory of this distribution and at
 // http://rust-lang.org/COPYRIGHT.
 //
@@ -17,8 +17,6 @@
 use core::comm::*;
 use core::comm;
 use core::io;
-use core::libc;
-use core::os;
 use core::result;
 use core::run;
 use core::str;
diff --git a/src/librustdoc/unindent_pass.rs b/src/librustdoc/unindent_pass.rs
index e78edf1fbf3..a7f195a35ee 100644
--- a/src/librustdoc/unindent_pass.rs
+++ b/src/librustdoc/unindent_pass.rs
@@ -1,4 +1,4 @@
-// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
+// Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
 // file at the top-level directory of this distribution and at
 // http://rust-lang.org/COPYRIGHT.
 //
@@ -22,7 +22,6 @@
 use core::prelude::*;
 
 use core::str;
-use core::task;
 use core::uint;
 use core::vec;
 use pass::Pass;
diff --git a/src/libstd/cell.rs b/src/libstd/cell.rs
index f6d4e966db9..87145acbb62 100644
--- a/src/libstd/cell.rs
+++ b/src/libstd/cell.rs
@@ -1,4 +1,4 @@
-// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
+// Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
 // file at the top-level directory of this distribution and at
 // http://rust-lang.org/COPYRIGHT.
 //
@@ -11,7 +11,6 @@
 //! A mutable, nullable memory location
 
 use cast::transmute_mut;
-use cmp;
 use prelude::*;
 use util::replace;
 
diff --git a/src/libstd/iterator.rs b/src/libstd/iterator.rs
index b13c4ca23e6..7be9e8c354e 100644
--- a/src/libstd/iterator.rs
+++ b/src/libstd/iterator.rs
@@ -20,7 +20,6 @@
 use cmp;
 use iter;
 use num::{Zero, One};
-use num;
 use prelude::*;
 
 /// An interface for dealing with "external iterators". These types of iterators
diff --git a/src/libstd/local_data.rs b/src/libstd/local_data.rs
index 6227f9ad388..82c01c998cf 100644
--- a/src/libstd/local_data.rs
+++ b/src/libstd/local_data.rs
@@ -1,4 +1,4 @@
-// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
+// Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
 // file at the top-level directory of this distribution and at
 // http://rust-lang.org/COPYRIGHT.
 //
@@ -29,7 +29,8 @@
 use prelude::*;
 
 use task::local_data_priv::{local_get, local_pop, local_modify, local_set, Handle};
-use task;
+
+#[cfg(test)] use task;
 
 /**
  * Indexes a task-local data slot. The function's code pointer is used for
diff --git a/src/libstd/rand/distributions.rs b/src/libstd/rand/distributions.rs
index a66e35f68df..cf2733976c4 100644
--- a/src/libstd/rand/distributions.rs
+++ b/src/libstd/rand/distributions.rs
@@ -21,7 +21,6 @@
 // could implement VIZIGNOR the ZIGNOR paper for more speed.
 
 use f64;
-use prelude::*;
 use rand::{Rng,Rand};
 
 mod ziggurat_tables;
diff --git a/src/libstd/rt/task.rs b/src/libstd/rt/task.rs
index 12c683120c8..eb7282bae05 100644
--- a/src/libstd/rt/task.rs
+++ b/src/libstd/rt/task.rs
@@ -20,7 +20,6 @@
 use rt::local::Local;
 use rt::logging::StdErrLogger;
 use super::local_heap::LocalHeap;
-use super::sched::Scheduler;
 
 pub struct Task {
     heap: LocalHeap,
diff --git a/src/libstd/task/mod.rs b/src/libstd/task/mod.rs
index 28fb73e6eef..b68abca8605 100644
--- a/src/libstd/task/mod.rs
+++ b/src/libstd/task/mod.rs
@@ -1,4 +1,4 @@
-// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
+// Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
 // file at the top-level directory of this distribution and at
 // http://rust-lang.org/COPYRIGHT.
 //
@@ -37,22 +37,22 @@
 
 use prelude::*;
 
-use cast;
 use cell::Cell;
 use cmp::Eq;
 use comm::{stream, Chan, GenericChan, GenericPort, Port};
-use comm;
-use ptr;
 use result::Result;
 use result;
 use rt::{context, OldTaskContext};
 use task::rt::{task_id, sched_id};
-use task;
 use unstable::finally::Finally;
 use util::replace;
 use util;
 
+#[cfg(test)] use cast;
 #[cfg(test)] use comm::SharedChan;
+#[cfg(test)] use comm;
+#[cfg(test)] use ptr;
+#[cfg(test)] use task;
 
 mod local_data_priv;
 pub mod rt;
diff --git a/src/libstd/task/spawn.rs b/src/libstd/task/spawn.rs
index 0b345b88d62..35cf6de3a15 100644
--- a/src/libstd/task/spawn.rs
+++ b/src/libstd/task/spawn.rs
@@ -1,4 +1,4 @@
-// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
+// Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
 // file at the top-level directory of this distribution and at
 // http://rust-lang.org/COPYRIGHT.
 //
@@ -79,7 +79,6 @@
 use cell::Cell;
 use container::Map;
 use comm::{Chan, GenericChan};
-use comm;
 use ptr;
 use hashmap::HashSet;
 use task::local_data_priv::{local_get, local_set, OldHandle};
@@ -89,13 +88,14 @@
 use task::{Success, TaskOpts, TaskResult, ThreadPerCore, ThreadPerTask};
 use task::{ExistingScheduler, SchedulerHandle};
 use task::unkillable;
-use task;
 use uint;
 use util;
 use unstable::sync::{Exclusive, exclusive};
 use rt::local::Local;
 
 #[cfg(test)] use task::default_task_opts;
+#[cfg(test)] use comm;
+#[cfg(test)] use task;
 
 macro_rules! move_it (
     { $x:expr } => ( unsafe { let y = *ptr::to_unsafe_ptr(&($x)); y } )
diff --git a/src/libstd/trie.rs b/src/libstd/trie.rs
index 460f29d597a..e5b1385974e 100644
--- a/src/libstd/trie.rs
+++ b/src/libstd/trie.rs
@@ -10,8 +10,6 @@
 
 //! An ordered map and set for integer keys implemented as a radix trie
 
-use local_data;
-use os;
 use prelude::*;
 use uint;
 use util::{swap, replace};
diff --git a/src/libstd/unstable/mod.rs b/src/libstd/unstable/mod.rs
index 1f73aa02b01..1e226da271d 100644
--- a/src/libstd/unstable/mod.rs
+++ b/src/libstd/unstable/mod.rs
@@ -1,4 +1,4 @@
-// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
+// Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
 // file at the top-level directory of this distribution and at
 // http://rust-lang.org/COPYRIGHT.
 //
@@ -14,7 +14,6 @@
 use comm;
 use libc;
 use prelude::*;
-use ptr;
 use task;
 
 pub mod at_exit;
diff --git a/src/libstd/util.rs b/src/libstd/util.rs
index 18fc6af3ac6..2b61356129e 100644
--- a/src/libstd/util.rs
+++ b/src/libstd/util.rs
@@ -11,7 +11,6 @@
 //! Miscellaneous helpers for common patterns.
 
 use cast;
-use local_data;
 use ptr;
 use prelude::*;
 use unstable::intrinsics;
diff --git a/src/libsyntax/ext/pipes/ast_builder.rs b/src/libsyntax/ext/pipes/ast_builder.rs
index 37d5e0206cb..08f1540918e 100644
--- a/src/libsyntax/ext/pipes/ast_builder.rs
+++ b/src/libsyntax/ext/pipes/ast_builder.rs
@@ -1,4 +1,4 @@
-// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
+// Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
 // file at the top-level directory of this distribution and at
 // http://rust-lang.org/COPYRIGHT.
 //
@@ -19,7 +19,6 @@
 use ast;
 use codemap::span;
 
-use core::str;
 use core::vec;
 
 // Transitional reexports so qquote can find the paths it is looking for
diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index 27dfc2c0a46..208ed1c41c8 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -92,7 +92,6 @@
 use opt_vec;
 use opt_vec::OptVec;
 
-use core::char;
 use core::either::Either;
 use core::either;
 use core::hashmap::HashSet;
diff --git a/src/libsyntax/parse/token.rs b/src/libsyntax/parse/token.rs
index b1a385ada07..f50b9f8936a 100644
--- a/src/libsyntax/parse/token.rs
+++ b/src/libsyntax/parse/token.rs
@@ -1,4 +1,4 @@
-// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
+// Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
 // file at the top-level directory of this distribution and at
 // http://rust-lang.org/COPYRIGHT.
 //
@@ -19,11 +19,9 @@
 use core::cast;
 use core::char;
 use core::cmp::Equiv;
-use core::hashmap::HashSet;
 use core::local_data;
 use core::str;
 use core::to_bytes;
-use core::vec;
 
 #[deriving(Encodable, Decodable, Eq)]
 pub enum binop {