diff --git a/bench/bin.rs b/bench/bin.rs
index f10a7655..ea0c2fb8 100644
--- a/bench/bin.rs
+++ b/bench/bin.rs
@@ -11,7 +11,7 @@
 #![crate_type="bin"]
 
 #![feature(box_syntax)]
-#![allow(unstable)]
+#![feature(core, collections, io, os, path, test)]
 
 extern crate test;
 
diff --git a/bench/tokenizer.rs b/bench/tokenizer.rs
index df1a77a4..9a8a1865 100644
--- a/bench/tokenizer.rs
+++ b/bench/tokenizer.rs
@@ -7,7 +7,8 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-use std::{io, os, cmp};
+use std::old_io as io;
+use std::{os, cmp};
 use std::default::Default;
 use std::vec::IntoIter;
 
@@ -36,7 +37,7 @@ struct Bench {
 }
 
 impl Bench {
-    fn new(name: &str, size: Option<uint>, clone_only: bool,
+    fn new(name: &str, size: Option<usize>, clone_only: bool,
            opts: TokenizerOpts) -> Bench {
         let mut path = os::self_exe_path().expect("can't get exe path");
         path.push("../data/bench/");
@@ -51,7 +52,7 @@ impl Bench {
         // Break the input into chunks of 1024 chars (= a few kB).
         // This simulates reading from the network.
         let mut input = vec![];
-        let mut total = 0u;
+        let mut total = 0us;
         while total < size {
             // The by_ref() call is important, otherwise we get wrong results!
             // See rust-lang/rust#18045.
@@ -90,7 +91,7 @@ impl TDynBenchFn for Bench {
     }
 }
 
-fn make_bench(name: &str, size: Option<uint>, clone_only: bool,
+fn make_bench(name: &str, size: Option<usize>, clone_only: bool,
               opts: TokenizerOpts) -> TestDescAndFn {
     TestDescAndFn {
         desc: TestDesc {
diff --git a/data/test/ignore b/data/test/ignore
index aa5b8cf1..c8376af3 100644
--- a/data/test/ignore
+++ b/data/test/ignore
@@ -14,7 +14,6 @@ tb: adoption01.dat-8
 tb: adoption01.dat-9
 tb: adoption02.dat-0
 tb: adoption02.dat-1
-tb: domjs-unsafe.dat-34
 tb: html5test-com.dat-20
 tb: isindex.dat-0
 tb: isindex.dat-1
@@ -81,7 +80,6 @@ tb: tests19.dat-96
 tb: tests19.dat-97
 tb: tests19.dat-98
 tb: tests19.dat-99
-tb: tests2.dat-37
 tb: tests2.dat-44
 tb: tests2.dat-9
 tb: tests22.dat-0
diff --git a/examples/html2html.rs b/examples/html2html.rs
index 91d07c55..5045f6a9 100644
--- a/examples/html2html.rs
+++ b/examples/html2html.rs
@@ -7,17 +7,19 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-/// Parse and re-serialize a HTML5 document.
-///
-/// This is meant to produce the exact same output (ignoring stderr) as
-///
-///   java -classpath htmlparser-1.4.jar nu.validator.htmlparser.tools.HTML2HTML
-///
-/// where htmlparser-1.4.jar comes from http://about.validator.nu/htmlparser/
+#![feature(io)]
+
+//! Parse and re-serialize a HTML5 document.
+//!
+//! This is meant to produce the exact same output (ignoring stderr) as
+//!
+//!   java -classpath htmlparser-1.4.jar nu.validator.htmlparser.tools.HTML2HTML
+//!
+//! where htmlparser-1.4.jar comes from http://about.validator.nu/htmlparser/
 
 extern crate html5ever;
 
-use std::io;
+use std::old_io as io;
 use std::default::Default;
 
 use html5ever::sink::rcdom::RcDom;
@@ -25,7 +27,6 @@ use html5ever::driver::ParseOpts;
 use html5ever::tree_builder::TreeBuilderOpts;
 use html5ever::{parse, one_input, serialize};
 
-#[allow(unstable)]
 fn main() {
     let input = io::stdin().read_to_string().unwrap();
     let dom: RcDom = parse(one_input(input), ParseOpts {
diff --git a/examples/noop-tokenize.rs b/examples/noop-tokenize.rs
index 2cd311aa..f368b764 100644
--- a/examples/noop-tokenize.rs
+++ b/examples/noop-tokenize.rs
@@ -9,12 +9,13 @@
 
 // Run a single benchmark once.  For use with profiling tools.
 
-#![allow(unstable)]
+#![feature(core, os, io, test, path)]
 
 extern crate test;
 extern crate html5ever;
 
-use std::{io, os};
+use std::old_io as io;
+use std::os;
 use std::default::Default;
 
 use test::black_box;
diff --git a/examples/noop-tree-builder.rs b/examples/noop-tree-builder.rs
index aa298fdb..7491dfbd 100644
--- a/examples/noop-tree-builder.rs
+++ b/examples/noop-tree-builder.rs
@@ -7,13 +7,13 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![allow(unstable)]
+#![feature(io)]
 
 extern crate string_cache;
 
 extern crate html5ever;
 
-use std::io;
+use std::old_io as io;
 use std::default::Default;
 use std::string::String;
 use std::collections::HashMap;
@@ -25,12 +25,12 @@ use html5ever::tokenizer::Attribute;
 use html5ever::tree_builder::{TreeSink, QuirksMode, NodeOrText};
 
 struct Sink {
-    next_id: uint,
-    names: HashMap<uint, QualName>,
+    next_id: usize,
+    names: HashMap<usize, QualName>,
 }
 
 impl Sink {
-    fn get_id(&mut self) -> uint {
+    fn get_id(&mut self) -> usize {
         let id = self.next_id;
         self.next_id += 1;
         id
@@ -38,33 +38,33 @@ impl Sink {
 }
 
 impl TreeSink for Sink {
-    type Handle = uint;
+    type Handle = usize;
 
-    fn get_document(&mut self) -> uint {
+    fn get_document(&mut self) -> usize {
         0
     }
 
-    fn same_node(&self, x: uint, y: uint) -> bool {
+    fn same_node(&self, x: usize, y: usize) -> bool {
         x == y
     }
 
-    fn elem_name(&self, target: uint) -> QualName {
+    fn elem_name(&self, target: usize) -> QualName {
         self.names.get(&target).expect("not an element").clone()
     }
 
-    fn create_element(&mut self, name: QualName, _attrs: Vec<Attribute>) -> uint {
+    fn create_element(&mut self, name: QualName, _attrs: Vec<Attribute>) -> usize {
         let id = self.get_id();
         self.names.insert(id, name);
         id
     }
 
-    fn create_comment(&mut self, _text: String) -> uint {
+    fn create_comment(&mut self, _text: String) -> usize {
         self.get_id()
     }
 
     fn append_before_sibling(&mut self,
-            _sibling: uint,
-            _new_node: NodeOrText<uint>) -> Result<(), NodeOrText<uint>> {
+            _sibling: usize,
+            _new_node: NodeOrText<usize>) -> Result<(), NodeOrText<usize>> {
         // `sibling` will have a parent unless a script moved it, and we're
         // not running scripts.  Therefore we can aways return `Ok(())`.
         Ok(())
@@ -72,12 +72,12 @@ impl TreeSink for Sink {
 
     fn parse_error(&mut self, _msg: CowString<'static>) { }
     fn set_quirks_mode(&mut self, _mode: QuirksMode) { }
-    fn append(&mut self, _parent: uint, _child: NodeOrText<uint>) { }
+    fn append(&mut self, _parent: usize, _child: NodeOrText<usize>) { }
 
     fn append_doctype_to_document(&mut self, _name: String, _public_id: String, _system_id: String) { }
-    fn add_attrs_if_missing(&mut self, _target: uint, _attrs: Vec<Attribute>) { }
-    fn remove_from_parent(&mut self, _target: uint) { }
-    fn mark_script_already_started(&mut self, _node: uint) { }
+    fn add_attrs_if_missing(&mut self, _target: usize, _attrs: Vec<Attribute>) { }
+    fn remove_from_parent(&mut self, _target: usize) { }
+    fn mark_script_already_started(&mut self, _node: usize) { }
 }
 
 fn main() {
diff --git a/examples/print-rcdom.rs b/examples/print-rcdom.rs
index 9cd42c7f..1997840e 100644
--- a/examples/print-rcdom.rs
+++ b/examples/print-rcdom.rs
@@ -7,8 +7,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![feature(plugin)]
-#![allow(unstable)]
+#![feature(plugin, io)]
 
 extern crate html5ever;
 
@@ -17,7 +16,7 @@ extern crate string_cache;
 #[macro_use]
 extern crate string_cache_macros;
 
-use std::io;
+use std::old_io as io;
 use std::iter::repeat;
 use std::default::Default;
 use std::string::String;
@@ -28,7 +27,7 @@ use html5ever::{parse, one_input};
 
 // This is not proper HTML serialization, of course.
 
-fn walk(indent: uint, handle: Handle) {
+fn walk(indent: usize, handle: Handle) {
     let node = handle.borrow();
     // FIXME: don't allocate
     print!("{}", repeat(" ").take(indent).collect::<String>());
diff --git a/examples/print-tree-actions.rs b/examples/print-tree-actions.rs
index b1d18157..0f4d0e33 100644
--- a/examples/print-tree-actions.rs
+++ b/examples/print-tree-actions.rs
@@ -7,13 +7,13 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![allow(unstable)]
+#![feature(io)]
 
 extern crate string_cache;
 
 extern crate html5ever;
 
-use std::io;
+use std::old_io as io;
 use std::default::Default;
 use std::string::String;
 use std::collections::HashMap;
@@ -25,12 +25,12 @@ use html5ever::tokenizer::Attribute;
 use html5ever::tree_builder::{TreeSink, QuirksMode, NodeOrText, AppendNode, AppendText};
 
 struct Sink {
-    next_id: uint,
-    names: HashMap<uint, QualName>,
+    next_id: usize,
+    names: HashMap<usize, QualName>,
 }
 
 impl Sink {
-    fn get_id(&mut self) -> uint {
+    fn get_id(&mut self) -> usize {
         let id = self.next_id;
         self.next_id += 1;
         id
@@ -38,13 +38,13 @@ impl Sink {
 }
 
 impl TreeSink for Sink {
-    type Handle = uint;
+    type Handle = usize;
 
     fn parse_error(&mut self, msg: CowString<'static>) {
         println!("Parse error: {}", msg);
     }
 
-    fn get_document(&mut self) -> uint {
+    fn get_document(&mut self) -> usize {
         0
     }
 
@@ -52,28 +52,28 @@ impl TreeSink for Sink {
         println!("Set quirks mode to {:?}", mode);
     }
 
-    fn same_node(&self, x: uint, y: uint) -> bool {
+    fn same_node(&self, x: usize, y: usize) -> bool {
         x == y
     }
 
-    fn elem_name(&self, target: uint) -> QualName {
+    fn elem_name(&self, target: usize) -> QualName {
         self.names.get(&target).expect("not an element").clone()
     }
 
-    fn create_element(&mut self, name: QualName, _attrs: Vec<Attribute>) -> uint {
+    fn create_element(&mut self, name: QualName, _attrs: Vec<Attribute>) -> usize {
         let id = self.get_id();
         println!("Created {:?} as {}", name, id);
         self.names.insert(id, name);
         id
     }
 
-    fn create_comment(&mut self, text: String) -> uint {
+    fn create_comment(&mut self, text: String) -> usize {
         let id = self.get_id();
         println!("Created comment \"{}\" as {}", text.escape_default(), id);
         id
     }
 
-    fn append(&mut self, parent: uint, child: NodeOrText<uint>) {
+    fn append(&mut self, parent: usize, child: NodeOrText<usize>) {
         match child {
             AppendNode(n)
                 => println!("Append node {} to {}", n, parent),
@@ -83,8 +83,8 @@ impl TreeSink for Sink {
     }
 
     fn append_before_sibling(&mut self,
-            sibling: uint,
-            new_node: NodeOrText<uint>) -> Result<(), NodeOrText<uint>> {
+            sibling: usize,
+            new_node: NodeOrText<usize>) -> Result<(), NodeOrText<usize>> {
         match new_node {
             AppendNode(n)
                 => println!("Append node {} before {}", n, sibling),
@@ -101,18 +101,18 @@ impl TreeSink for Sink {
         println!("Append doctype: {} {} {}", name, public_id, system_id);
     }
 
-    fn add_attrs_if_missing(&mut self, target: uint, attrs: Vec<Attribute>) {
+    fn add_attrs_if_missing(&mut self, target: usize, attrs: Vec<Attribute>) {
         println!("Add missing attributes to {}:", target);
         for attr in attrs.into_iter() {
             println!("    {:?} = {}", attr.name, attr.value);
         }
     }
 
-    fn remove_from_parent(&mut self, target: uint) {
+    fn remove_from_parent(&mut self, target: usize) {
         println!("Remove {} from parent", target);
     }
 
-    fn mark_script_already_started(&mut self, node: uint) {
+    fn mark_script_already_started(&mut self, node: usize) {
         println!("Mark script {} as already started", node);
     }
 }
diff --git a/examples/tokenize.rs b/examples/tokenize.rs
index 79f3dbd5..b7cad825 100644
--- a/examples/tokenize.rs
+++ b/examples/tokenize.rs
@@ -7,11 +7,11 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![allow(unstable)]
+#![feature(core, io)]
 
 extern crate html5ever;
 
-use std::io;
+use std::old_io as io;
 use std::default::Default;
 
 use html5ever::tokenizer::{TokenSink, Token, TokenizerOpts, ParseError};
diff --git a/html5lib-tests b/html5lib-tests
index a9badff0..11aec478 160000
--- a/html5lib-tests
+++ b/html5lib-tests
@@ -1 +1 @@
-Subproject commit a9badff0cd2fe337170769d42ca2df5e96d30f97
+Subproject commit 11aec478545744fe89ba17bac70fbcacdd76922b
diff --git a/macros/src/lib.rs b/macros/src/lib.rs
index c33d01cb..ec458ec2 100644
--- a/macros/src/lib.rs
+++ b/macros/src/lib.rs
@@ -11,12 +11,12 @@
 #![crate_type="dylib"]
 
 #![feature(plugin_registrar, quote, old_orphan_check)]
+#![feature(rustc_private, std_misc, core, hash, collections, path, io)]
 #![deny(warnings)]
-#![allow(unstable)]
 
 extern crate syntax;
 extern crate rustc;
-extern crate serialize;
+extern crate "serialize" as rustc_serialize;
 
 use rustc::plugin::Registry;
 
diff --git a/macros/src/named_entities.rs b/macros/src/named_entities.rs
index f1780cb3..63cccc42 100644
--- a/macros/src/named_entities.rs
+++ b/macros/src/named_entities.rs
@@ -9,14 +9,14 @@
 
 #![allow(unused_imports)]  // for quotes
 
-use std::io;
+use std::old_io as io;
 use std::path;
 use std::str::FromStr;
-use serialize::json;
-use serialize::json::Json;
-use serialize::Decodable;
 use std::collections::HashMap;
 
+use rustc_serialize::json;
+use rustc_serialize::json::Json;
+use rustc_serialize::Decodable;
 use syntax::codemap::Span;
 use syntax::ast::{Path, ExprLit, Lit_, TokenTree, TtToken};
 use syntax::parse::token;
@@ -25,7 +25,7 @@ use syntax::ext::source_util::expand_file;
 
 // A struct matching the entries in entities.json.
 // Simplifies JSON parsing because we can use Decodable.
-#[derive(Decodable)]
+#[derive(RustcDecodable)]
 struct CharRef {
     codepoints: Vec<u32>,
     //characters: String,  // Present in the file but we don't need it
diff --git a/src/lib.rs b/src/lib.rs
index 1417dccf..aa4ed242 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -10,12 +10,14 @@
 #![crate_name="html5ever"]
 #![crate_type="dylib"]
 
-#![feature(plugin, old_impl_check, int_uint, box_syntax)]
+#![feature(plugin, int_uint, box_syntax)]
+#![feature(core, hash, collections, alloc)]
+#![cfg_attr(not(for_c), feature(rustc_private, io))]
+#![cfg_attr(for_c, feature(libc))]
 #![deny(warnings)]
-#![allow(unused_parens, unstable)]
+#![allow(unused_parens)]
 
-// Don't implicitly pull in things from std::*
-// This helps us make a C-friendly library.
+// FIXME(#63): switch back to using std
 #![no_std]
 
 extern crate alloc;
diff --git a/src/serialize/mod.rs b/src/serialize/mod.rs
index a0d3fbe0..5d5cb9e8 100644
--- a/src/serialize/mod.rs
+++ b/src/serialize/mod.rs
@@ -9,7 +9,7 @@
 
 use core::prelude::*;
 
-use std::io::{Writer, IoResult};
+use std::old_io::{Writer, IoResult};
 use core::default::Default;
 use collections::vec::Vec;
 
diff --git a/src/sink/owned_dom.rs b/src/sink/owned_dom.rs
index 4ea02fd8..f5964371 100644
--- a/src/sink/owned_dom.rs
+++ b/src/sink/owned_dom.rs
@@ -7,9 +7,10 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![experimental="This module uses unsafe code, has not been thoroughly \
-                 audited, and the performance gains vs. RcDom have not \
-                 been demonstrated"]
+#![unstable(feature="string_cache_namespace",
+    reason="This module uses unsafe code, has not been thoroughly \
+            audited, and the performance gains vs. RcDom have not \
+            been demonstrated")]
 
 //! A simple DOM where every node is owned by its parent.
 //!
@@ -37,7 +38,7 @@ use alloc::boxed::Box;
 use collections::vec::Vec;
 use collections::string::String;
 use std::string::CowString;
-use std::io::{Writer, IoResult};
+use std::old_io::{Writer, IoResult};
 use std::collections::HashSet;
 use std::ops::{Deref, DerefMut};
 
diff --git a/src/sink/rcdom.rs b/src/sink/rcdom.rs
index 48f4104e..5465cc57 100644
--- a/src/sink/rcdom.rs
+++ b/src/sink/rcdom.rs
@@ -28,7 +28,7 @@ use alloc::rc::{Rc, Weak};
 use collections::vec::Vec;
 use collections::string::String;
 use std::string::CowString;
-use std::io::{Writer, IoResult};
+use std::old_io::{Writer, IoResult};
 use std::ops::DerefMut;
 
 use string_cache::QualName;
diff --git a/src/tokenizer/char_ref/mod.rs b/src/tokenizer/char_ref/mod.rs
index c7d7ba59..22aad2db 100644
--- a/src/tokenizer/char_ref/mod.rs
+++ b/src/tokenizer/char_ref/mod.rs
@@ -113,9 +113,8 @@ impl CharRefTokenizer {
     }
 }
 
-#[old_impl_check]
-impl<Sink: TokenSink> CharRefTokenizer {
-    pub fn step(&mut self, tokenizer: &mut Tokenizer<Sink>) -> Status {
+impl CharRefTokenizer {
+    pub fn step<Sink: TokenSink>(&mut self, tokenizer: &mut Tokenizer<Sink>) -> Status {
         if self.result.is_some() {
             return Done;
         }
@@ -131,7 +130,7 @@ impl<Sink: TokenSink> CharRefTokenizer {
         }
     }
 
-    fn do_begin(&mut self, tokenizer: &mut Tokenizer<Sink>) -> Status {
+    fn do_begin<Sink: TokenSink>(&mut self, tokenizer: &mut Tokenizer<Sink>) -> Status {
         match unwrap_or_return!(tokenizer.peek(), Stuck) {
             '\t' | '\n' | '\x0C' | ' ' | '<' | '&'
                 => self.finish_none(),
@@ -152,7 +151,7 @@ impl<Sink: TokenSink> CharRefTokenizer {
         }
     }
 
-    fn do_octothorpe(&mut self, tokenizer: &mut Tokenizer<Sink>) -> Status {
+    fn do_octothorpe<Sink: TokenSink>(&mut self, tokenizer: &mut Tokenizer<Sink>) -> Status {
         let c = unwrap_or_return!(tokenizer.peek(), Stuck);
         match c {
             'x' | 'X' => {
@@ -169,7 +168,7 @@ impl<Sink: TokenSink> CharRefTokenizer {
         Progress
     }
 
-    fn do_numeric(&mut self, tokenizer: &mut Tokenizer<Sink>, base: u32) -> Status {
+    fn do_numeric<Sink: TokenSink>(&mut self, tokenizer: &mut Tokenizer<Sink>, base: u32) -> Status {
         let c = unwrap_or_return!(tokenizer.peek(), Stuck);
         match c.to_digit(base as uint) {
             Some(n) => {
@@ -194,7 +193,7 @@ impl<Sink: TokenSink> CharRefTokenizer {
         }
     }
 
-    fn do_numeric_semicolon(&mut self, tokenizer: &mut Tokenizer<Sink>) -> Status {
+    fn do_numeric_semicolon<Sink: TokenSink>(&mut self, tokenizer: &mut Tokenizer<Sink>) -> Status {
         match unwrap_or_return!(tokenizer.peek(), Stuck) {
             ';' => tokenizer.discard_char(),
             _   => tokenizer.emit_error(Borrowed("Semicolon missing after numeric character reference")),
@@ -202,7 +201,7 @@ impl<Sink: TokenSink> CharRefTokenizer {
         self.finish_numeric(tokenizer)
     }
 
-    fn unconsume_numeric(&mut self, tokenizer: &mut Tokenizer<Sink>) -> Status {
+    fn unconsume_numeric<Sink: TokenSink>(&mut self, tokenizer: &mut Tokenizer<Sink>) -> Status {
         let mut unconsume = String::from_str("#");
         match self.hex_marker {
             Some(c) => unconsume.push(c),
@@ -214,7 +213,7 @@ impl<Sink: TokenSink> CharRefTokenizer {
         self.finish_none()
     }
 
-    fn finish_numeric(&mut self, tokenizer: &mut Tokenizer<Sink>) -> Status {
+    fn finish_numeric<Sink: TokenSink>(&mut self, tokenizer: &mut Tokenizer<Sink>) -> Status {
         fn conv(n: u32) -> char {
             from_u32(n).expect("invalid char missed by error handling cases")
         }
@@ -247,7 +246,7 @@ impl<Sink: TokenSink> CharRefTokenizer {
         self.finish_one(c)
     }
 
-    fn do_named(&mut self, tokenizer: &mut Tokenizer<Sink>) -> Status {
+    fn do_named<Sink: TokenSink>(&mut self, tokenizer: &mut Tokenizer<Sink>) -> Status {
         let c = unwrap_or_return!(tokenizer.get_char(), Stuck);
         self.name_buf_mut().push(c);
         match data::NAMED_ENTITIES.get(self.name_buf().as_slice()) {
@@ -267,18 +266,18 @@ impl<Sink: TokenSink> CharRefTokenizer {
         }
     }
 
-    fn emit_name_error(&mut self, tokenizer: &mut Tokenizer<Sink>) {
+    fn emit_name_error<Sink: TokenSink>(&mut self, tokenizer: &mut Tokenizer<Sink>) {
         let msg = format_if!(tokenizer.opts.exact_errors,
             "Invalid character reference",
             "Invalid character reference &{}", self.name_buf().as_slice());
         tokenizer.emit_error(msg);
     }
 
-    fn unconsume_name(&mut self, tokenizer: &mut Tokenizer<Sink>) {
+    fn unconsume_name<Sink: TokenSink>(&mut self, tokenizer: &mut Tokenizer<Sink>) {
         tokenizer.unconsume(self.name_buf_opt.take().unwrap());
     }
 
-    fn finish_named(&mut self,
+    fn finish_named<Sink: TokenSink>(&mut self,
             tokenizer: &mut Tokenizer<Sink>,
             end_char: Option<char>) -> Status {
         match self.name_match {
@@ -360,7 +359,7 @@ impl<Sink: TokenSink> CharRefTokenizer {
         }
     }
 
-    fn do_bogus_name(&mut self, tokenizer: &mut Tokenizer<Sink>) -> Status {
+    fn do_bogus_name<Sink: TokenSink>(&mut self, tokenizer: &mut Tokenizer<Sink>) -> Status {
         let c = unwrap_or_return!(tokenizer.get_char(), Stuck);
         self.name_buf_mut().push(c);
         match c {
@@ -372,7 +371,7 @@ impl<Sink: TokenSink> CharRefTokenizer {
         self.finish_none()
     }
 
-    pub fn end_of_file(&mut self, tokenizer: &mut Tokenizer<Sink>) {
+    pub fn end_of_file<Sink: TokenSink>(&mut self, tokenizer: &mut Tokenizer<Sink>) {
         while self.result.is_none() {
             match self.state {
                 Begin => drop(self.finish_none()),
diff --git a/src/tree_builder/rules.rs b/src/tree_builder/rules.rs
index e12c50df..14104c95 100644
--- a/src/tree_builder/rules.rs
+++ b/src/tree_builder/rules.rs
@@ -957,7 +957,7 @@ impl<Handle, Sink> TreeBuilderStep<Handle>
             InColumnGroup => match_token!(token {
                 CharacterTokens(NotSplit, text) => SplitWhitespace(text),
                 CharacterTokens(Whitespace, text) => self.append_text(text),
-                CommentToken(text) => self.append_comment_to_html(text),
+                CommentToken(text) => self.append_comment(text),
 
                 <html> => self.step(InBody, token),
 
@@ -1158,7 +1158,7 @@ impl<Handle, Sink> TreeBuilderStep<Handle>
                 </optgroup> => {
                     if self.open_elems.len() >= 2
                         && self.current_node_named(atom!(option))
-                        && self.html_elem_named(self.open_elems[1].clone(),
+                        && self.html_elem_named(self.open_elems[self.open_elems.len() - 2].clone(),
                             atom!(optgroup)) {
                         self.pop();
                     }
diff --git a/tests/html5ever-external-test.rs b/tests/html5ever-external-test.rs
index 585b4ae2..44249eed 100644
--- a/tests/html5ever-external-test.rs
+++ b/tests/html5ever-external-test.rs
@@ -11,7 +11,7 @@
 #![crate_type="bin"]
 
 #![feature(plugin)]
-#![allow(unstable)]
+#![feature(rustc_private, core, collections, io, os, path, std_misc, test)]
 
 extern crate test;
 extern crate serialize;
@@ -22,7 +22,8 @@ extern crate string_cache_macros;
 
 extern crate html5ever;
 
-use std::{io, os};
+use std::old_io as io;
+use std::os;
 use std::str::FromStr;
 use std::collections::HashSet;
 use test::test_main;
diff --git a/tests/tokenizer.rs b/tests/tokenizer.rs
index bacda6c6..cd925c30 100644
--- a/tests/tokenizer.rs
+++ b/tests/tokenizer.rs
@@ -32,12 +32,12 @@ use string_cache::{Atom, QualName};
 
 // Return all ways of splitting the string into at most n
 // possibly-empty pieces.
-fn splits(s: &str, n: uint) -> Vec<Vec<String>> {
+fn splits(s: &str, n: usize) -> Vec<Vec<String>> {
     if n == 1 {
         return vec!(vec!(s.to_string()));
     }
 
-    let mut points: Vec<uint> = s.char_indices().map(|(n,_)| n).collect();
+    let mut points: Vec<usize> = s.char_indices().map(|(n,_)| n).collect();
     points.push(s.len());
 
     // do this with iterators?
@@ -291,7 +291,7 @@ fn unescape_json(js: &Json) -> Json {
     }
 }
 
-fn mk_test(desc: String, insplits: Vec<Vec<String>>, expect: Vec<Token>, opts: TokenizerOpts)
+fn mk_test(desc: String, input: String, expect: Vec<Token>, opts: TokenizerOpts)
         -> TestDescAndFn {
     TestDescAndFn {
         desc: TestDesc {
@@ -300,6 +300,8 @@ fn mk_test(desc: String, insplits: Vec<Vec<String>>, expect: Vec<Token>, opts: T
             should_fail: No,
         },
         testfn: DynTestFn(Thunk::new(move || {
+            // Split up the input at different points to test incremental tokenization.
+            let insplits = splits(input.as_slice(), 3);
             for input in insplits.into_iter() {
                 // Clone 'input' so we have it for the failure message.
                 // Also clone opts.  If we don't, we get the wrong
@@ -332,9 +334,6 @@ fn mk_tests(tests: &mut Vec<TestDescAndFn>, path_str: &str, js: &Json) {
         expect = unescape_json(&expect);
     }
 
-    // Split up the input at different points to test incremental tokenization.
-    let insplits = splits(input.as_slice(), 3);
-
     // Some tests have a last start tag name.
     let start_tag = obj.get(&"lastStartTag".to_string()).map(|s| s.get_str());
 
@@ -364,7 +363,7 @@ fn mk_tests(tests: &mut Vec<TestDescAndFn>, path_str: &str, js: &Json) {
             }
 
             let expect_toks = json_to_tokens(&expect, exact_errors);
-            tests.push(mk_test(newdesc, insplits.clone(), expect_toks, TokenizerOpts {
+            tests.push(mk_test(newdesc, input.clone(), expect_toks, TokenizerOpts {
                 exact_errors: exact_errors,
                 initial_state: state,
                 last_start_tag_name: start_tag.clone(),
diff --git a/tests/tree_builder.rs b/tests/tree_builder.rs
index c637da69..76c47738 100644
--- a/tests/tree_builder.rs
+++ b/tests/tree_builder.rs
@@ -9,7 +9,7 @@
 
 use util::foreach_html5lib_test;
 
-use std::io;
+use std::old_io as io;
 use std::iter::repeat;
 use std::mem::replace;
 use std::default::Default;
@@ -65,7 +65,7 @@ fn parse_tests<It: Iterator<Item=String>>(mut lines: It) -> Vec<HashMap<String,
     tests
 }
 
-fn serialize(buf: &mut String, indent: uint, handle: Handle) {
+fn serialize(buf: &mut String, indent: usize, handle: Handle) {
     buf.push_str("|");
     buf.push_str(repeat(" ").take(indent).collect::<String>().as_slice());
 
@@ -127,7 +127,7 @@ fn make_test(
         tests: &mut Vec<TestDescAndFn>,
         ignores: &HashSet<String>,
         path_str: &str,
-        idx: uint,
+        idx: usize,
         fields: HashMap<String, String>) {
 
     let get_field = |&:key| {
diff --git a/tests/util.rs b/tests/util.rs
index 54b356ff..2db65bb9 100644
--- a/tests/util.rs
+++ b/tests/util.rs
@@ -7,7 +7,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-use std::io;
+use std::old_io as io;
 use std::path::Path;
 
 pub fn foreach_html5lib_test<Mk>(