diff --git a/.travis.yml b/.travis.yml
index abd0a8fe346f0..0546f6827a6f5 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -8,13 +8,13 @@ git:
   depth: 1
   submodules: false
 
-osx_image: xcode8.2
-
 matrix:
+  fast_finish: true
   include:
     # Linux builders, all docker images
-    - env: IMAGE=arm-android DEPLOY=1
+    - env: IMAGE=android DEPLOY=1
     - env: IMAGE=cross DEPLOY=1
+    - env: IMAGE=linux-tested-targets DEPLOY=1
     - env: IMAGE=dist-arm-linux DEPLOY=1
     - env: IMAGE=dist-armv7-aarch64-linux DEPLOY=1
     - env: IMAGE=dist-freebsd DEPLOY=1
@@ -23,16 +23,17 @@ matrix:
     - env: IMAGE=dist-powerpc-linux DEPLOY=1
     - env: IMAGE=dist-powerpc64-linux DEPLOY=1
     - env: IMAGE=dist-s390x-linux-netbsd DEPLOY=1
-    - env: IMAGE=i686-gnu DEPLOY=1
+    - env: IMAGE=dist-x86-linux DEPLOY=1
+    - env: IMAGE=emscripten
+    - env: IMAGE=i686-gnu
     - env: IMAGE=i686-gnu-nopt
-    - env: IMAGE=x86_64-gnu DEPLOY=1
+    - env: IMAGE=x86_64-gnu
     - env: IMAGE=x86_64-gnu-full-bootstrap
     - env: IMAGE=x86_64-gnu-aux
     - env: IMAGE=x86_64-gnu-debug
     - env: IMAGE=x86_64-gnu-nopt
     - env: IMAGE=x86_64-gnu-make
     - env: IMAGE=x86_64-gnu-llvm-3.7 ALLOW_PR=1 RUST_BACKTRACE=1
-    - env: IMAGE=x86_64-musl DEPLOY=1
     - env: IMAGE=x86_64-gnu-distcheck
 
     # OSX builders
@@ -41,6 +42,7 @@ matrix:
         RUST_CONFIGURE_ARGS=--build=x86_64-apple-darwin
         SRC=.
       os: osx
+      osx_image: xcode8.2
       before_script: &osx_before_script >
         ulimit -c unlimited
       install: &osx_install_sccache >
@@ -50,7 +52,7 @@ matrix:
         echo 'bt all' > cmds;
         for file in $(ls /cores); do
           echo core file $file;
-          lldb -c $file `which ld` -b -s cmds;
+          lldb -c /cores/$file `which ld` -b -s cmds;
         done
 
     - env: >
@@ -59,6 +61,7 @@ matrix:
         SRC=.
         DEPLOY=1
       os: osx
+      osx_image: xcode8.2
       before_script: *osx_before_script
       install: *osx_install_sccache
       after_failure: *osx_after_failure
@@ -67,6 +70,7 @@ matrix:
         RUST_CONFIGURE_ARGS=--build=x86_64-apple-darwin --disable-rustbuild
         SRC=.
       os: osx
+      osx_image: xcode8.2
       before_script: *osx_before_script
       install: *osx_install_sccache
       after_failure: *osx_after_failure
@@ -76,6 +80,7 @@ matrix:
         SRC=.
         DEPLOY=1
       os: osx
+      osx_image: xcode8.2
       before_script: *osx_before_script
       install: *osx_install_sccache
       after_failure: *osx_after_failure
@@ -119,11 +124,9 @@ before_deploy:
   - mkdir -p deploy/$TRAVIS_COMMIT
   - >
       if [ "$TRAVIS_OS_NAME" == "osx" ]; then
-          cp build/dist/*.tar.gz deploy/$TRAVIS_COMMIT &&
-          find "deploy/$TRAVIS_COMMIT" -maxdepth 1 -type f -exec sh -c 'shasum -a 256 -b "{}" > "{}.sha256"' \;;
+          cp build/dist/*.tar.gz deploy/$TRAVIS_COMMIT;
       else
-          cp obj/build/dist/*.tar.gz deploy/$TRAVIS_COMMIT &&
-          find "deploy/$TRAVIS_COMMIT" -maxdepth 1 -type f -exec sh -c 'sha256sum -b "{}" > "{}.sha256"' \;;
+          cp obj/build/dist/*.tar.gz deploy/$TRAVIS_COMMIT;
       fi
 
 deploy:
diff --git a/RELEASES.md b/RELEASES.md
index a2241c20d7419..74ab03f7778e5 100644
--- a/RELEASES.md
+++ b/RELEASES.md
@@ -1,3 +1,244 @@
+Version 1.15.0 (2017-02-02)
+===========================
+
+Language
+--------
+
+* Basic procedural macros allowing custom `#[derive]`, aka "macros 1.1", are
+  stable. This allows popular code-generating crates like Serde and Diesel to
+  work ergonomically. [RFC 1681].
+* [Tuple structs may be empty. Unary and empty tuple structs may be instantiated
+  with curly braces][36868]. Part of [RFC 1506].
+* [A number of minor changes to name resolution have been activated][37127].
+  They add up to more consistent semantics, allowing for future evolution of
+  Rust macros. Specified in [RFC 1560], see its section on ["changes"] for
+  details of what is different. The breaking changes here have been transitioned
+  through the [`legacy_imports`] lint since 1.14, with no known regressions.
+* [In `macro_rules`, `path` fragments can now be parsed as type parameter
+  bounds][38279]
+* [`?Sized` can be used in `where` clauses][37791]
+* [There is now a limit on the size of monomorphized types and it can be
+  modified with the `#![type_size_limit]` crate attribute, similarly to
+  the `#![recursion_limit]` attribute][37789]
+
+Compiler
+--------
+
+* [On Windows, the compiler will apply dllimport attributes when linking to
+  extern functions][37973]. Additional attributes and flags can control which
+  library kind is linked and its name. [RFC 1717].
+* [Rust-ABI symbols are no longer exported from cdylibs][38117]
+* [The `--test` flag works with procedural macro crates][38107]
+* [Fix `extern "aapcs" fn` ABI][37814]
+* [The `-C no-stack-check` flag is deprecated][37636]. It does nothing.
+* [The `format!` expander recognizes incorrect `printf` and shell-style
+  formatting directives and suggests the correct format][37613].
+* [Only report one error for all unused imports in an import list][37456]
+
+Compiler Performance
+--------------------
+
+* [Avoid unnecessary `mk_ty` calls in `Ty::super_fold_with`][37705]
+* [Avoid more unnecessary `mk_ty` calls in `Ty::super_fold_with`][37979]
+* [Don't clone in `UnificationTable::probe`][37848]
+* [Remove `scope_auxiliary` to cut RSS by 10%][37764]
+* [Use small vectors in type walker][37760]
+* [Macro expansion performance was improved][37701]
+* [Change `HirVec<P<T>>` to `HirVec<T>` in `hir::Expr`][37642]
+* [Replace FNV with a faster hash function][37229]
+
+Stabilized APIs
+---------------
+
+* [`std::iter::Iterator::min_by`]
+* [`std::iter::Iterator::max_by`]
+* [`std::os::*::fs::FileExt`]
+* [`std::sync::atomic::Atomic*::get_mut`]
+* [`std::sync::atomic::Atomic*::into_inner`]
+* [`std::vec::IntoIter::as_slice`]
+* [`std::vec::IntoIter::as_mut_slice`]
+* [`std::sync::mpsc::Receiver::try_iter`]
+* [`std::os::unix::process::CommandExt::before_exec`]
+* [`std::rc::Rc::strong_count`]
+* [`std::rc::Rc::weak_count`]
+* [`std::sync::Arc::strong_count`]
+* [`std::sync::Arc::weak_count`]
+* [`std::char::encode_utf8`]
+* [`std::char::encode_utf16`]
+* [`std::cell::Ref::clone`]
+* [`std::io::Take::into_inner`]
+
+Libraries
+---------
+
+* [The standard sorting algorithm has been rewritten for dramatic performance
+  improvements][38192]. It is a hybrid merge sort, drawing influences from
+  Timsort. Previously it was a naive merge sort.
+* [`Iterator::nth` no longer has a `Sized` bound][38134]
+* [`Extend<&T>` is specialized for `Vec` where `T: Copy`][38182] to improve
+  performance.
+* [`chars().count()` is much faster][37888] and so are [`chars().last()`
+  and `char_indices().last()`][37882]
+* [Fix ARM Objective-C ABI in `std::env::args`][38146]
+* [Chinese characters display correctly in `fmt::Debug`][37855]
+* [Derive `Default` for `Duration`][37699]
+* [Support creation of anonymous pipes on WinXP/2k][37677]
+* [`mpsc::RecvTimeoutError` implements `Error`][37527]
+* [Don't pass overlapped handles to processes][38835]
+
+Cargo
+-----
+
+* [In this release, Cargo build scripts no longer have access to the `OUT_DIR`
+  environment variable at build time via `env!("OUT_DIR")`][cargo/3368]. They
+  should instead check the variable at runtime with `std::env`. That the value
+  was set at build time was a bug, and incorrect when cross-compiling. This
+  change is known to cause breakage.
+* [Add `--all` flag to `cargo test`][cargo/3221]
+* [Compile statically against the MSVC CRT][cargo/3363]
+* [Mix feature flags into fingerprint/metadata shorthash][cargo/3102]
+* [Link OpenSSL statically on OSX][cargo/3311]
+* [Apply new fingerprinting to build dir outputs][cargo/3310]
+* [Test for bad path overrides with summaries][cargo/3336]
+* [Require `cargo install --vers` to take a semver version][cargo/3338]
+* [Fix retrying crate downloads for network errors][cargo/3348]
+* [Implement string lookup for `build.rustflags` config key][cargo/3356]
+* [Emit more info on --message-format=json][cargo/3319]
+* [Assume `build.rs` in the same directory as `Cargo.toml` is a build script][cargo/3361]
+* [Don't ignore errors in workspace manifest][cargo/3409]
+* [Fix `--message-format JSON` when rustc emits non-JSON warnings][cargo/3410]
+
+Tooling
+-------
+
+* [Test runners (binaries built with `--test`) now support a `--list` argument
+  that lists the tests it contains][38185]
+* [Test runners now support a `--exact` argument that makes the test filter
+  match exactly, instead of matching only a substring of the test name][38181]
+* [rustdoc supports a `--playground-url` flag][37763]
+* [rustdoc provides more details about `#[should_panic]` errors][37749]
+
+Misc
+----
+
+* [The Rust build system is now written in Rust][37817]. The Makefiles may
+  continue to be used in this release by passing `--disable-rustbuild` to the
+  configure script, but they will be deleted soon. Note that the new build
+  system uses a different on-disk layout that will likely affect any scripts
+  building Rust.
+* [Rust supports i686-unknown-openbsd][38086]. Tier 3 support. No testing or
+  releases.
+* [Rust supports the MSP430][37627]. Tier 3 support. No testing or releases.
+* [Rust supports the ARMv5TE architecture][37615]. Tier 3 support. No testing or
+  releases.
+
+Compatibility Notes
+-------------------
+
+* [A number of minor changes to name resolution have been activated][37127].
+  They add up to more consistent semantics, allowing for future evolution of
+  Rust macros. Specified in [RFC 1560], see its section on ["changes"] for
+  details of what is different. The breaking changes here have been transitioned
+  through the [`legacy_imports`] lint since 1.14, with no known regressions.
+* [In this release, Cargo build scripts no longer have access to the `OUT_DIR`
+  environment variable at build time via `env!("OUT_DIR")`][cargo/3368]. They
+  should instead check the variable at runtime with `std::env`. That the value
+  was set at build time was a bug, and incorrect when cross-compiling. This
+  change is known to cause breakage.
+* [Higher-ranked lifetimes are no longer allowed to appear _only_ in associated
+  types][33685]. The [`hr_lifetime_in_assoc_type` lint] has been a warning since
+  1.10 and is now an error by default. It will become a hard error in the near
+  future.
+* [The semantics relating modules to file system directories are changing in
+  minor ways][37602]. This is captured in the new `legacy_directory_ownership`
+  lint, which is a warning in this release, and will become a hard error in the
+  future.
+* [Rust-ABI symbols are no longer exported from cdylibs][38117]
+* [Once `Peekable` peeks a `None` it will return that `None` without re-querying
+  the underlying iterator][37834]
+
+["changes"]: https://github.com/rust-lang/rfcs/blob/master/text/1560-name-resolution.md#changes-to-name-resolution-rules
+[33685]: https://github.com/rust-lang/rust/issues/33685
+[36868]: https://github.com/rust-lang/rust/pull/36868
+[37127]: https://github.com/rust-lang/rust/pull/37127
+[37229]: https://github.com/rust-lang/rust/pull/37229
+[37456]: https://github.com/rust-lang/rust/pull/37456
+[37527]: https://github.com/rust-lang/rust/pull/37527
+[37602]: https://github.com/rust-lang/rust/pull/37602
+[37613]: https://github.com/rust-lang/rust/pull/37613
+[37615]: https://github.com/rust-lang/rust/pull/37615
+[37636]: https://github.com/rust-lang/rust/pull/37636
+[37642]: https://github.com/rust-lang/rust/pull/37642
+[37677]: https://github.com/rust-lang/rust/pull/37677
+[37699]: https://github.com/rust-lang/rust/pull/37699
+[37701]: https://github.com/rust-lang/rust/pull/37701
+[37705]: https://github.com/rust-lang/rust/pull/37705
+[37749]: https://github.com/rust-lang/rust/pull/37749
+[37760]: https://github.com/rust-lang/rust/pull/37760
+[37763]: https://github.com/rust-lang/rust/pull/37763
+[37764]: https://github.com/rust-lang/rust/pull/37764
+[37789]: https://github.com/rust-lang/rust/pull/37789
+[37791]: https://github.com/rust-lang/rust/pull/37791
+[37814]: https://github.com/rust-lang/rust/pull/37814
+[37817]: https://github.com/rust-lang/rust/pull/37817
+[37834]: https://github.com/rust-lang/rust/pull/37834
+[37848]: https://github.com/rust-lang/rust/pull/37848
+[37855]: https://github.com/rust-lang/rust/pull/37855
+[37882]: https://github.com/rust-lang/rust/pull/37882
+[37888]: https://github.com/rust-lang/rust/pull/37888
+[37973]: https://github.com/rust-lang/rust/pull/37973
+[37979]: https://github.com/rust-lang/rust/pull/37979
+[38086]: https://github.com/rust-lang/rust/pull/38086
+[38107]: https://github.com/rust-lang/rust/pull/38107
+[38117]: https://github.com/rust-lang/rust/pull/38117
+[38134]: https://github.com/rust-lang/rust/pull/38134
+[38146]: https://github.com/rust-lang/rust/pull/38146
+[38181]: https://github.com/rust-lang/rust/pull/38181
+[38182]: https://github.com/rust-lang/rust/pull/38182
+[38185]: https://github.com/rust-lang/rust/pull/38185
+[38192]: https://github.com/rust-lang/rust/pull/38192
+[38279]: https://github.com/rust-lang/rust/pull/38279
+[38835]: https://github.com/rust-lang/rust/pull/38835
+[RFC 1492]: https://github.com/rust-lang/rfcs/blob/master/text/1492-dotdot-in-patterns.md
+[RFC 1506]: https://github.com/rust-lang/rfcs/blob/master/text/1506-adt-kinds.md
+[RFC 1560]: https://github.com/rust-lang/rfcs/blob/master/text/1560-name-resolution.md
+[RFC 1681]: https://github.com/rust-lang/rfcs/blob/master/text/1681-macros-1.1.md
+[RFC 1717]: https://github.com/rust-lang/rfcs/blob/master/text/1717-dllimport.md
+[`hr_lifetime_in_assoc_type` lint]: https://github.com/rust-lang/rust/issues/33685
+[`legacy_imports`]: https://github.com/rust-lang/rust/pull/38271
+[cargo/3102]: https://github.com/rust-lang/cargo/pull/3102
+[cargo/3221]: https://github.com/rust-lang/cargo/pull/3221
+[cargo/3310]: https://github.com/rust-lang/cargo/pull/3310
+[cargo/3311]: https://github.com/rust-lang/cargo/pull/3311
+[cargo/3319]: https://github.com/rust-lang/cargo/pull/3319
+[cargo/3336]: https://github.com/rust-lang/cargo/pull/3336
+[cargo/3338]: https://github.com/rust-lang/cargo/pull/3338
+[cargo/3348]: https://github.com/rust-lang/cargo/pull/3348
+[cargo/3356]: https://github.com/rust-lang/cargo/pull/3356
+[cargo/3361]: https://github.com/rust-lang/cargo/pull/3361
+[cargo/3363]: https://github.com/rust-lang/cargo/pull/3363
+[cargo/3368]: https://github.com/rust-lang/cargo/issues/3368
+[cargo/3409]: https://github.com/rust-lang/cargo/pull/3409
+[cargo/3410]: https://github.com/rust-lang/cargo/pull/3410
+[`std::iter::Iterator::min_by`]: https://doc.rust-lang.org/std/iter/trait.Iterator.html#method.min_by
+[`std::iter::Iterator::max_by`]: https://doc.rust-lang.org/std/iter/trait.Iterator.html#method.max_by
+[`std::os::*::fs::FileExt`]: https://doc.rust-lang.org/std/os/unix/fs/trait.FileExt.html
+[`std::sync::atomic::Atomic*::get_mut`]: https://doc.rust-lang.org/std/sync/atomic/struct.AtomicU8.html#method.get_mut
+[`std::sync::atomic::Atomic*::into_inner`]: https://doc.rust-lang.org/std/sync/atomic/struct.AtomicU8.html#method.into_inner
+[`std::vec::IntoIter::as_slice`]: https://doc.rust-lang.org/std/vec/struct.IntoIter.html#method.as_slice
+[`std::vec::IntoIter::as_mut_slice`]: https://doc.rust-lang.org/std/vec/struct.IntoIter.html#method.as_mut_slice
+[`std::sync::mpsc::Receiver::try_iter`]: https://doc.rust-lang.org/std/sync/mpsc/struct.Receiver.html#method.try_iter
+[`std::os::unix::process::CommandExt::before_exec`]: https://doc.rust-lang.org/std/os/unix/process/trait.CommandExt.html#tymethod.before_exec
+[`std::rc::Rc::strong_count`]: https://doc.rust-lang.org/std/rc/struct.Rc.html#method.strong_count
+[`std::rc::Rc::weak_count`]: https://doc.rust-lang.org/std/rc/struct.Rc.html#method.weak_count
+[`std::sync::Arc::strong_count`]: https://doc.rust-lang.org/std/sync/struct.Arc.html#method.strong_count
+[`std::sync::Arc::weak_count`]: https://doc.rust-lang.org/std/sync/struct.Arc.html#method.weak_count
+[`std::char::encode_utf8`]: https://doc.rust-lang.org/std/primitive.char.html#method.encode_utf8
+[`std::char::encode_utf16`]: https://doc.rust-lang.org/std/primitive.char.html#method.encode_utf16
+[`std::cell::Ref::clone`]: https://doc.rust-lang.org/std/cell/struct.Ref.html#method.clone
+[`std::io::Take::into_inner`]: https://doc.rust-lang.org/std/io/struct.Take.html#method.into_inner
+
+
 Version 1.14.0 (2016-12-22)
 ===========================
 
diff --git a/appveyor.yml b/appveyor.yml
index 346ef0d8faad7..cd61f95875f7f 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -11,8 +11,8 @@ environment:
     SCRIPT: python x.py test && python x.py dist
     DEPLOY: 1
   - MSYS_BITS: 32
-    RUST_CONFIGURE_ARGS: --build=i686-pc-windows-msvc
-    SCRIPT: python x.py test && python x.py dist
+    RUST_CONFIGURE_ARGS: --build=i686-pc-windows-msvc --target=i586-pc-windows-msvc
+    SCRIPT: python x.py test --host i686-pc-windows-msvc --target i686-pc-windows-msvc && python x.py dist
     DEPLOY: 1
 
   # MSVC makefiles
@@ -73,6 +73,9 @@ environment:
     MINGW_DIR: mingw64
     DEPLOY: 1
 
+matrix:
+  fast_finish: true
+
 clone_depth: 1
 build: false
 
@@ -131,9 +134,6 @@ before_deploy:
   - ps: |
         New-Item -Path deploy -ItemType directory
         Get-ChildItem -Path build\dist -Filter '*.tar.gz' | Move-Item -Destination deploy
-        Get-FileHash .\deploy\* | ForEach-Object {
-          [io.file]::WriteAllText($_.Path + ".sha256", $_.Hash.ToLower() + "`n")
-        }
         Get-ChildItem -Path deploy | Foreach-Object {
           Push-AppveyorArtifact $_.FullName -FileName ${env:APPVEYOR_REPO_COMMIT}/$_
         }
@@ -147,7 +147,7 @@ deploy:
     bucket: rust-lang-ci
     set_public: true
     region: us-east-1
-    artifact: /.*\.(tar.gz|sha256)/
+    artifact: /.*\.tar.gz/
     folder: rustc-builds
     on:
       branch: auto
diff --git a/src/bootstrap/cc.rs b/src/bootstrap/cc.rs
index aa70e24d95222..54c8194678e61 100644
--- a/src/bootstrap/cc.rs
+++ b/src/bootstrap/cc.rs
@@ -121,10 +121,14 @@ fn set_compiler(cfg: &mut gcc::Config,
         }
 
         "mips-unknown-linux-musl" => {
-            cfg.compiler("mips-linux-musl-gcc");
+            if cfg.get_compiler().path().to_str() == Some("gcc") {
+                cfg.compiler("mips-linux-musl-gcc");
+            }
         }
         "mipsel-unknown-linux-musl" => {
-            cfg.compiler("mipsel-linux-musl-gcc");
+            if cfg.get_compiler().path().to_str() == Some("gcc") {
+                cfg.compiler("mipsel-linux-musl-gcc");
+            }
         }
 
         t if t.contains("musl") => {
diff --git a/src/bootstrap/compile.rs b/src/bootstrap/compile.rs
index 0eeb799672cf2..079f93e7331f1 100644
--- a/src/bootstrap/compile.rs
+++ b/src/bootstrap/compile.rs
@@ -213,7 +213,11 @@ pub fn rustc(build: &Build, target: &str, compiler: &Compiler) {
     if let Some(s) = target_config.and_then(|c| c.llvm_config.as_ref()) {
         cargo.env("CFG_LLVM_ROOT", s);
     }
-    if build.config.llvm_static_stdcpp {
+    // Building with a static libstdc++ is only supported on linux right now,
+    // not for MSVC or OSX
+    if build.config.llvm_static_stdcpp &&
+       !target.contains("windows") &&
+       !target.contains("apple") {
         cargo.env("LLVM_STATIC_STDCPP",
                   compiler_file(build.cxx(target), "libstdc++.a"));
     }
diff --git a/src/bootstrap/flags.rs b/src/bootstrap/flags.rs
index 1be823417d765..c5bbfd89b2787 100644
--- a/src/bootstrap/flags.rs
+++ b/src/bootstrap/flags.rs
@@ -287,8 +287,8 @@ To learn more about a subcommand, run `./x.py <command> -h`
             build: m.opt_str("build").unwrap_or_else(|| {
                 env::var("BUILD").unwrap()
             }),
-            host: m.opt_strs("host"),
-            target: m.opt_strs("target"),
+            host: split(m.opt_strs("host")),
+            target: split(m.opt_strs("target")),
             config: cfg_file,
             src: m.opt_str("src").map(PathBuf::from),
             jobs: m.opt_str("jobs").map(|j| j.parse().unwrap()),
@@ -309,3 +309,7 @@ impl Subcommand {
         }
     }
 }
+
+fn split(s: Vec<String>) -> Vec<String> {
+    s.iter().flat_map(|s| s.split(',')).map(|s| s.to_string()).collect()
+}
diff --git a/src/bootstrap/sanity.rs b/src/bootstrap/sanity.rs
index 66bdd5e00f43d..8e79c2d27d195 100644
--- a/src/bootstrap/sanity.rs
+++ b/src/bootstrap/sanity.rs
@@ -45,7 +45,7 @@ pub fn check(build: &mut Build) {
             let target = path.join(cmd);
             let mut cmd_alt = cmd.to_os_string();
             cmd_alt.push(".exe");
-            if target.exists() ||
+            if target.is_file() ||
                target.with_extension("exe").exists() ||
                target.join(cmd_alt).exists() {
                 return Some(target);
diff --git a/src/ci/docker/README.md b/src/ci/docker/README.md
new file mode 100644
index 0000000000000..9a0a4c8cb530a
--- /dev/null
+++ b/src/ci/docker/README.md
@@ -0,0 +1,145 @@
+# Docker images for CI
+
+This folder contains a bunch of docker images used by the continuous integration
+(CI) of Rust. An script is accompanied (`run.sh`) with these images to actually
+execute them. To test out an image execute:
+
+```
+./src/ci/docker/run.sh $image_name
+```
+
+for example:
+
+```
+./src/ci/docker/run.sh x86_64-gnu
+```
+
+Images will output artifacts in an `obj` dir at the root of a repository.
+
+## Cross toolchains
+
+A number of these images take quite a long time to compile as they're building
+whole gcc toolchains to do cross builds with. Much of this is relatively
+self-explanatory but some images use [crosstool-ng] which isn't quite as self
+explanatory. Below is a description of where these `*.config` files come form,
+how to generate them, and how the existing ones were generated.
+
+[crosstool-ng]: https://github.com/crosstool-ng/crosstool-ng
+
+### Generating a `.config` file
+
+If you have a `linux-cross` image lying around you can use that and skip the
+next two steps.
+
+- First we spin up a container and copy `build_toolchain_root.sh` into it. All
+  these steps are outside the container:
+
+```
+# Note: We use ubuntu:15.10 because that's the "base" of linux-cross Docker
+# image
+$ docker run -it ubuntu:15.10 bash
+$ docker ps
+CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS               NAMES
+cfbec05ed730        ubuntu:15.10        "bash"              16 seconds ago      Up 15 seconds                           drunk_murdock
+$ docker cp build_toolchain_root.sh drunk_murdock:/
+```
+
+- Then inside the container we build crosstool-ng by simply calling the bash
+  script we copied in the previous step:
+
+```
+$ bash build_toolchain_root.sh
+```
+
+- Now, inside the container run the following command to configure the
+  toolchain. To get a clue of which options need to be changed check the next
+  section and come back.
+
+```
+$ ct-ng menuconfig
+```
+
+- Finally, we retrieve the `.config` file from the container and give it a
+  meaningful name. This is done outside the container.
+
+```
+$ docker drunk_murdock:/.config arm-linux-gnueabi.config
+```
+
+- Now you can shutdown the container or repeat the two last steps to generate a
+  new `.config` file.
+
+### Toolchain configuration
+
+Changes on top of the default toolchain configuration used to generate the
+`.config` files in this directory. The changes are formatted as follows:
+
+```
+$category > $option = $value -- $comment
+```
+
+### `arm-linux-gnueabi.config`
+
+For targets: `arm-unknown-linux-gnueabi`
+
+- Path and misc options > Prefix directory = /x-tools/${CT\_TARGET}
+- Target options > Target Architecture = arm
+- Target options > Architecture level = armv6 -- (+)
+- Target options > Floating point = software (no FPU) -- (\*)
+- Operating System > Target OS = linux
+- Operating System > Linux kernel version = 3.2.72 -- Precise kernel
+- C-library > glibc version = 2.14.1
+- C compiler > gcc version = 4.9.3
+- C compiler > C++ = ENABLE -- to cross compile LLVM
+
+### `arm-linux-gnueabihf.config`
+
+For targets: `arm-unknown-linux-gnueabihf`
+
+- Path and misc options > Prefix directory = /x-tools/${CT\_TARGET}
+- Target options > Target Architecture = arm
+- Target options > Architecture level = armv6 -- (+)
+- Target options > Use specific FPU = vfp -- (+)
+- Target options > Floating point = hardware (FPU) -- (\*)
+- Target options > Default instruction set mode = arm -- (+)
+- Operating System > Target OS = linux
+- Operating System > Linux kernel version = 3.2.72 -- Precise kernel
+- C-library > glibc version = 2.14.1
+- C compiler > gcc version = 4.9.3
+- C compiler > C++ = ENABLE -- to cross compile LLVM
+
+### `armv7-linux-gnueabihf.config`
+
+For targets: `armv7-unknown-linux-gnueabihf`
+
+- Path and misc options > Prefix directory = /x-tools/${CT\_TARGET}
+- Target options > Target Architecture = arm
+- Target options > Suffix to the arch-part = v7
+- Target options > Architecture level = armv7-a -- (+)
+- Target options > Use specific FPU = vfpv3-d16 -- (\*)
+- Target options > Floating point = hardware (FPU) -- (\*)
+- Target options > Default instruction set mode = thumb -- (\*)
+- Operating System > Target OS = linux
+- Operating System > Linux kernel version = 3.2.72 -- Precise kernel
+- C-library > glibc version = 2.14.1
+- C compiler > gcc version = 4.9.3
+- C compiler > C++ = ENABLE -- to cross compile LLVM
+
+(\*) These options have been selected to match the configuration of the arm
+      toolchains shipped with Ubuntu 15.10
+(+) These options have been selected to match the gcc flags we use to compile C
+    libraries like jemalloc. See the mk/cfg/arm(v7)-uknown-linux-gnueabi{,hf}.mk
+    file in Rust's source code.
+
+## `aarch64-linux-gnu.config`
+
+For targets: `aarch64-unknown-linux-gnu`
+
+- Path and misc options > Prefix directory = /x-tools/${CT\_TARGET}
+- Target options > Target Architecture = arm
+- Target options > Bitness = 64-bit
+- Operating System > Target OS = linux
+- Operating System > Linux kernel version = 4.2.6
+- C-library > glibc version = 2.17 -- aarch64 support was introduced in this version
+- C compiler > gcc version = 5.2.0
+- C compiler > C++ = ENABLE -- to cross compile LLVM
diff --git a/src/ci/docker/arm-android/Dockerfile b/src/ci/docker/android/Dockerfile
similarity index 90%
rename from src/ci/docker/arm-android/Dockerfile
rename to src/ci/docker/android/Dockerfile
index d81666e84262f..e3748af501fb8 100644
--- a/src/ci/docker/arm-android/Dockerfile
+++ b/src/ci/docker/android/Dockerfile
@@ -53,8 +53,4 @@ ENV RUST_CONFIGURE_ARGS \
 # to all the targets above eventually.
 ENV SCRIPT \
   python2.7 ../x.py test --target arm-linux-androideabi && \
-  python2.7 ../x.py dist \
-      --target arm-linux-androideabi \
-      --target armv7-linux-androideabi \
-      --target i686-linux-android \
-      --target aarch64-linux-android
+  python2.7 ../x.py dist --target $TARGETS
diff --git a/src/ci/docker/arm-android/accept-licenses.sh b/src/ci/docker/android/accept-licenses.sh
similarity index 100%
rename from src/ci/docker/arm-android/accept-licenses.sh
rename to src/ci/docker/android/accept-licenses.sh
diff --git a/src/ci/docker/arm-android/install-ndk.sh b/src/ci/docker/android/install-ndk.sh
similarity index 100%
rename from src/ci/docker/arm-android/install-ndk.sh
rename to src/ci/docker/android/install-ndk.sh
diff --git a/src/ci/docker/arm-android/install-sdk.sh b/src/ci/docker/android/install-sdk.sh
similarity index 100%
rename from src/ci/docker/arm-android/install-sdk.sh
rename to src/ci/docker/android/install-sdk.sh
diff --git a/src/ci/docker/arm-android/start-emulator.sh b/src/ci/docker/android/start-emulator.sh
similarity index 100%
rename from src/ci/docker/arm-android/start-emulator.sh
rename to src/ci/docker/android/start-emulator.sh
diff --git a/src/ci/docker/cross/Dockerfile b/src/ci/docker/cross/Dockerfile
index 7872397645136..8f947caf2cbf5 100644
--- a/src/ci/docker/cross/Dockerfile
+++ b/src/ci/docker/cross/Dockerfile
@@ -10,7 +10,12 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
   git \
   cmake \
   sudo \
-  xz-utils
+  xz-utils \
+  zlib1g-dev \
+  g++-arm-linux-gnueabi \
+  g++-arm-linux-gnueabihf \
+  bzip2 \
+  patch
 
 ENV SCCACHE_DIGEST=7237e38e029342fa27b7ac25412cb9d52554008b12389727320bd533fd7f05b6a96d55485f305caf95e5c8f5f97c3313e10012ccad3e752aba2518f3522ba783
 RUN curl -L https://api.pub.build.mozilla.org/tooltool/sha512/$SCCACHE_DIGEST | \
@@ -21,21 +26,50 @@ RUN curl -OL https://github.com/Yelp/dumb-init/releases/download/v1.2.0/dumb-ini
     rm dumb-init_*.deb
 ENTRYPOINT ["/usr/bin/dumb-init", "--"]
 
+WORKDIR /tmp
+
+COPY build-rumprun.sh /tmp/
+RUN ./build-rumprun.sh
+
+COPY build-arm-musl.sh /tmp/
+RUN ./build-arm-musl.sh
+
+# originally from
+# https://downloads.openwrt.org/snapshots/trunk/ar71xx/generic/OpenWrt-Toolchain-ar71xx-generic_gcc-5.3.0_musl-1.1.16.Linux-x86_64.tar.bz2
+RUN mkdir /usr/local/mips-linux-musl
+RUN curl -L https://s3.amazonaws.com/rust-lang-ci/rust-ci-mirror/OpenWrt-Toolchain-ar71xx-generic_gcc-5.3.0_musl-1.1.16.Linux-x86_64.tar.bz2 | \
+      tar xjf - -C /usr/local/mips-linux-musl --strip-components=2
+RUN for file in /usr/local/mips-linux-musl/bin/mips-openwrt-linux-*; do \
+      ln -s $file /usr/local/bin/`basename $file`; \
+    done
+
+# Note that this originally came from:
+# https://downloads.openwrt.org/snapshots/trunk/malta/generic/OpenWrt-Toolchain-malta-le_gcc-5.3.0_musl-1.1.15.Linux-x86_64.tar.bz2
+RUN mkdir /usr/local/mipsel-linux-musl
+RUN curl -L https://s3.amazonaws.com/rust-lang-ci/libc/OpenWrt-Toolchain-malta-le_gcc-5.3.0_musl-1.1.15.Linux-x86_64.tar.bz2 | \
+      tar xjf - -C /usr/local/mipsel-linux-musl --strip-components=2
+RUN for file in /usr/local/mipsel-linux-musl/bin/mipsel-openwrt-linux-*; do \
+      ln -s $file /usr/local/bin/`basename $file`; \
+    done
+
 ENV TARGETS=asmjs-unknown-emscripten
 ENV TARGETS=$TARGETS,wasm32-unknown-emscripten
+ENV TARGETS=$TARGETS,x86_64-rumprun-netbsd
+ENV TARGETS=$TARGETS,mips-unknown-linux-musl
+ENV TARGETS=$TARGETS,mipsel-unknown-linux-musl
+ENV TARGETS=$TARGETS,arm-unknown-linux-musleabi
+ENV TARGETS=$TARGETS,arm-unknown-linux-musleabihf
+ENV TARGETS=$TARGETS,armv7-unknown-linux-musleabihf
+
+ENV CC_mipsel_unknown_linux_musl=mipsel-openwrt-linux-gcc \
+    CC_mips_unknown_linux_musl=mips-openwrt-linux-gcc
 
-#ENV TARGETS=$TARGETS,mips-unknown-linux-musl
-#ENV TARGETS=$TARGETS,arm-unknown-linux-musleabi
-#ENV TARGETS=$TARGETS,arm-unknown-linux-musleabihf
-#ENV TARGETS=$TARGETS,armv7-unknown-linux-musleabihf
-#ENV TARGETS=$TARGETS,x86_64-rumprun-netbsd
+# Suppress some warnings in the openwrt toolchains we downloaded
+ENV STAGING_DIR=/tmp
 
 ENV RUST_CONFIGURE_ARGS \
       --target=$TARGETS \
-      --enable-rustbuild
-
-# Just a smoke test in dist to see if this works for now, we should expand this
-# to all the targets above eventually.
-ENV SCRIPT \
-  python2.7 ../x.py build && \
-  python2.7 ../x.py dist --target wasm32-unknown-emscripten
+      --musl-root-arm=/usr/local/arm-linux-musleabi \
+      --musl-root-armhf=/usr/local/arm-linux-musleabihf \
+      --musl-root-armv7=/usr/local/armv7-linux-musleabihf
+ENV SCRIPT python2.7 ../x.py dist --target $TARGETS
diff --git a/src/ci/docker/cross/build-arm-musl.sh b/src/ci/docker/cross/build-arm-musl.sh
new file mode 100755
index 0000000000000..938e69834e434
--- /dev/null
+++ b/src/ci/docker/cross/build-arm-musl.sh
@@ -0,0 +1,120 @@
+#!/bin/bash
+# Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+# file at the top-level directory of this distribution and at
+# http://rust-lang.org/COPYRIGHT.
+#
+# Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+# http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+# <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+# option. This file may not be copied, modified, or distributed
+# except according to those terms.
+
+set -ex
+
+MUSL=1.1.16
+
+hide_output() {
+  set +x
+  on_err="
+echo ERROR: An error was encountered with the build.
+cat /tmp/build.log
+exit 1
+"
+  trap "$on_err" ERR
+  bash -c "while true; do sleep 30; echo \$(date) - building ...; done" &
+  PING_LOOP_PID=$!
+  $@ &> /tmp/build.log
+  trap - ERR
+  kill $PING_LOOP_PID
+  rm /tmp/build.log
+  set -x
+}
+
+curl -O https://www.musl-libc.org/releases/musl-$MUSL.tar.gz
+tar xf musl-$MUSL.tar.gz
+cd musl-$MUSL
+CC=arm-linux-gnueabi-gcc \
+CFLAGS="-march=armv6 -marm" \
+    hide_output ./configure \
+        --prefix=/usr/local/arm-linux-musleabi \
+        --enable-wrapper=gcc
+hide_output make -j$(nproc)
+hide_output make install
+cd ..
+rm -rf musl-$MUSL
+
+tar xf musl-$MUSL.tar.gz
+cd musl-$MUSL
+CC=arm-linux-gnueabihf-gcc \
+CFLAGS="-march=armv6 -marm" \
+    hide_output ./configure \
+        --prefix=/usr/local/arm-linux-musleabihf \
+        --enable-wrapper=gcc
+hide_output make -j$(nproc)
+hide_output make install
+cd ..
+rm -rf musl-$MUSL
+
+tar xf musl-$MUSL.tar.gz
+cd musl-$MUSL
+CC=arm-linux-gnueabihf-gcc \
+CFLAGS="-march=armv7-a" \
+    hide_output ./configure \
+        --prefix=/usr/local/armv7-linux-musleabihf \
+        --enable-wrapper=gcc
+hide_output make -j$(nproc)
+hide_output make install
+cd ..
+rm -rf musl-$MUSL*
+
+ln -nsf ../arm-linux-musleabi/bin/musl-gcc /usr/local/bin/arm-linux-musleabi-gcc
+ln -nsf ../arm-linux-musleabihf/bin/musl-gcc /usr/local/bin/arm-linux-musleabihf-gcc
+ln -nsf ../armv7-linux-musleabihf/bin/musl-gcc /usr/local/bin/armv7-linux-musleabihf-gcc
+
+curl -L https://github.com/llvm-mirror/llvm/archive/release_39.tar.gz | tar xzf -
+curl -L https://github.com/llvm-mirror/libunwind/archive/release_39.tar.gz | tar xzf -
+
+mkdir libunwind-build
+cd libunwind-build
+cmake ../libunwind-release_39 \
+          -DLLVM_PATH=/tmp/llvm-release_39 \
+          -DLIBUNWIND_ENABLE_SHARED=0 \
+          -DCMAKE_C_COMPILER=arm-linux-gnueabi-gcc \
+          -DCMAKE_CXX_COMPILER=arm-linux-gnueabi-g++ \
+          -DCMAKE_C_FLAGS="-march=armv6 -marm" \
+          -DCMAKE_CXX_FLAGS="-march=armv6 -marm"
+make -j$(nproc)
+cp lib/libunwind.a /usr/local/arm-linux-musleabi/lib
+cd ..
+rm -rf libunwind-build
+
+mkdir libunwind-build
+cd libunwind-build
+cmake ../libunwind-release_39 \
+          -DLLVM_PATH=/tmp/llvm-release_39 \
+          -DLIBUNWIND_ENABLE_SHARED=0 \
+          -DCMAKE_C_COMPILER=arm-linux-gnueabihf-gcc \
+          -DCMAKE_CXX_COMPILER=arm-linux-gnueabihf-g++ \
+          -DCMAKE_C_FLAGS="-march=armv6 -marm" \
+          -DCMAKE_CXX_FLAGS="-march=armv6 -marm"
+make -j$(nproc)
+cp lib/libunwind.a /usr/local/arm-linux-musleabihf/lib
+cd ..
+rm -rf libunwind-build
+
+mkdir libunwind-build
+cd libunwind-build
+cmake ../libunwind-release_39 \
+          -DLLVM_PATH=/tmp/llvm-release_39 \
+          -DLIBUNWIND_ENABLE_SHARED=0 \
+          -DCMAKE_C_COMPILER=arm-linux-gnueabihf-gcc \
+          -DCMAKE_CXX_COMPILER=arm-linux-gnueabihf-g++ \
+          -DCMAKE_C_FLAGS="-march=armv7-a" \
+          -DCMAKE_CXX_FLAGS="-march=armv7-a"
+make -j$(nproc)
+cp lib/libunwind.a /usr/local/armv7-linux-musleabihf/lib
+cd ..
+rm -rf libunwind-build
+
+rm -rf libunwind-release_39
+rm -rf llvm-release_39
diff --git a/src/ci/docker/cross/build-rumprun.sh b/src/ci/docker/cross/build-rumprun.sh
new file mode 100755
index 0000000000000..59b1c9b641535
--- /dev/null
+++ b/src/ci/docker/cross/build-rumprun.sh
@@ -0,0 +1,38 @@
+#!/bin/bash
+# Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+# file at the top-level directory of this distribution and at
+# http://rust-lang.org/COPYRIGHT.
+#
+# Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+# http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+# <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+# option. This file may not be copied, modified, or distributed
+# except according to those terms.
+
+set -ex
+
+hide_output() {
+  set +x
+  on_err="
+echo ERROR: An error was encountered with the build.
+cat /tmp/build.log
+exit 1
+"
+  trap "$on_err" ERR
+  bash -c "while true; do sleep 30; echo \$(date) - building ...; done" &
+  PING_LOOP_PID=$!
+  $@ &> /tmp/build.log
+  trap - ERR
+  kill $PING_LOOP_PID
+  rm /tmp/build.log
+  set -x
+}
+
+git clone https://github.com/rumpkernel/rumprun
+cd rumprun
+git reset --hard 39a97f37a85e44c69b662f6b97b688fbe892603b
+git submodule update --init
+
+CC=cc hide_output ./build-rr.sh -d /usr/local hw
+cd ..
+rm -rf rumprun
diff --git a/src/ci/docker/dist-arm-linux/Dockerfile b/src/ci/docker/dist-arm-linux/Dockerfile
index 1aafc669d1023..03ca4c28078b6 100644
--- a/src/ci/docker/dist-arm-linux/Dockerfile
+++ b/src/ci/docker/dist-arm-linux/Dockerfile
@@ -1,19 +1,29 @@
 FROM ubuntu:16.04
 
 RUN apt-get update && apt-get install -y --no-install-recommends \
+  automake \
+  bison \
+  bzip2 \
+  ca-certificates \
+  cmake \
+  curl \
+  file \
+  flex \
   g++ \
+  gawk \
+  gdb \
+  git \
+  gperf \
+  help2man \
+  libncurses-dev \
+  libtool-bin \
   make \
-  file \
-  curl \
-  ca-certificates \
+  patch \
   python2.7 \
-  git \
-  cmake \
   sudo \
-  gdb \
-  xz-utils \
-  g++-arm-linux-gnueabi \
-  g++-arm-linux-gnueabihf
+  texinfo \
+  wget \
+  xz-utils
 
 ENV SCCACHE_DIGEST=7237e38e029342fa27b7ac25412cb9d52554008b12389727320bd533fd7f05b6a96d55485f305caf95e5c8f5f97c3313e10012ccad3e752aba2518f3522ba783
 RUN curl -L https://api.pub.build.mozilla.org/tooltool/sha512/$SCCACHE_DIGEST | \
@@ -24,11 +34,47 @@ RUN curl -OL https://github.com/Yelp/dumb-init/releases/download/v1.2.0/dumb-ini
     rm dumb-init_*.deb
 ENTRYPOINT ["/usr/bin/dumb-init", "--"]
 
-ENV RUST_CONFIGURE_ARGS \
-      --host=arm-unknown-linux-gnueabi,arm-unknown-linux-gnueabihf
-ENV SCRIPT \
-      python2.7 ../x.py dist \
-        --host arm-unknown-linux-gnueabi \
-        --target arm-unknown-linux-gnueabi \
-        --host arm-unknown-linux-gnueabihf \
-        --target arm-unknown-linux-gnueabihf
+# Ubuntu 16.04 (this contianer) ships with make 4, but something in the
+# toolchains we build below chokes on that, so go back to make 3
+RUN curl https://ftp.gnu.org/gnu/make/make-3.81.tar.gz | tar xzf - && \
+      cd make-3.81 && \
+      ./configure --prefix=/usr && \
+      make && \
+      make install && \
+      cd .. && \
+      rm -rf make-3.81
+
+RUN curl http://crosstool-ng.org/download/crosstool-ng/crosstool-ng-1.22.0.tar.bz2 | \
+      tar xjf - && \
+      cd crosstool-ng && \
+      ./configure --prefix=/usr/local && \
+      make -j$(nproc) && \
+      make install && \
+      cd .. && \
+      rm -rf crosstool-ng
+
+RUN groupadd -r rustbuild && useradd -m -r -g rustbuild rustbuild
+RUN mkdir /x-tools && chown rustbuild:rustbuild /x-tools
+USER rustbuild
+WORKDIR /tmp
+
+COPY arm-linux-gnueabihf.config arm-linux-gnueabi.config build-toolchains.sh /tmp/
+RUN ./build-toolchains.sh
+
+USER root
+
+ENV PATH=$PATH:/x-tools/arm-unknown-linux-gnueabi/bin
+ENV PATH=$PATH:/x-tools/arm-unknown-linux-gnueabihf/bin
+
+ENV CC_arm_unknown_linux_gnueabi=arm-unknown-linux-gnueabi-gcc \
+    AR_arm_unknown_linux_gnueabi=arm-unknown-linux-gnueabi-ar \
+    CXX_arm_unknown_linux_gnueabi=arm-unknown-linux-gnueabi-g++ \
+    CC_arm_unknown_linux_gnueabihf=arm-unknown-linux-gnueabihf-gcc \
+    AR_arm_unknown_linux_gnueabihf=arm-unknown-linux-gnueabihf-ar \
+    CXX_arm_unknown_linux_gnueabihf=arm-unknown-linux-gnueabihf-g++
+
+ENV HOSTS=arm-unknown-linux-gnueabi
+ENV HOSTS=$HOSTS,arm-unknown-linux-gnueabihf
+
+ENV RUST_CONFIGURE_ARGS --host=$HOSTS
+ENV SCRIPT python2.7 ../x.py dist --host $HOSTS --target $HOSTS
diff --git a/src/ci/docker/dist-arm-linux/arm-linux-gnueabi.config b/src/ci/docker/dist-arm-linux/arm-linux-gnueabi.config
new file mode 100644
index 0000000000000..f73ad069550e1
--- /dev/null
+++ b/src/ci/docker/dist-arm-linux/arm-linux-gnueabi.config
@@ -0,0 +1,560 @@
+#
+# Automatically generated file; DO NOT EDIT.
+# Crosstool-NG Configuration
+#
+CT_CONFIGURE_has_make381=y
+CT_MODULES=y
+
+#
+# Paths and misc options
+#
+
+#
+# crosstool-NG behavior
+#
+# CT_OBSOLETE is not set
+# CT_EXPERIMENTAL is not set
+# CT_DEBUG_CT is not set
+
+#
+# Paths
+#
+CT_LOCAL_TARBALLS_DIR=""
+CT_WORK_DIR="${CT_TOP_DIR}/.build"
+CT_PREFIX_DIR="/x-tools/${CT_TARGET}"
+CT_INSTALL_DIR="${CT_PREFIX_DIR}"
+CT_RM_RF_PREFIX_DIR=y
+CT_REMOVE_DOCS=y
+CT_INSTALL_DIR_RO=y
+CT_STRIP_HOST_TOOLCHAIN_EXECUTABLES=y
+# CT_STRIP_TARGET_TOOLCHAIN_EXECUTABLES is not set
+
+#
+# Downloading
+#
+# CT_FORBID_DOWNLOAD is not set
+# CT_FORCE_DOWNLOAD is not set
+CT_CONNECT_TIMEOUT=10
+# CT_ONLY_DOWNLOAD is not set
+# CT_USE_MIRROR is not set
+
+#
+# Extracting
+#
+# CT_FORCE_EXTRACT is not set
+CT_OVERIDE_CONFIG_GUESS_SUB=y
+# CT_ONLY_EXTRACT is not set
+CT_PATCH_BUNDLED=y
+# CT_PATCH_LOCAL is not set
+# CT_PATCH_BUNDLED_LOCAL is not set
+# CT_PATCH_LOCAL_BUNDLED is not set
+# CT_PATCH_BUNDLED_FALLBACK_LOCAL is not set
+# CT_PATCH_LOCAL_FALLBACK_BUNDLED is not set
+# CT_PATCH_NONE is not set
+CT_PATCH_ORDER="bundled"
+
+#
+# Build behavior
+#
+CT_PARALLEL_JOBS=0
+CT_LOAD=""
+CT_USE_PIPES=y
+CT_EXTRA_CFLAGS_FOR_BUILD=""
+CT_EXTRA_LDFLAGS_FOR_BUILD=""
+CT_EXTRA_CFLAGS_FOR_HOST=""
+CT_EXTRA_LDFLAGS_FOR_HOST=""
+# CT_CONFIG_SHELL_SH is not set
+# CT_CONFIG_SHELL_ASH is not set
+CT_CONFIG_SHELL_BASH=y
+# CT_CONFIG_SHELL_CUSTOM is not set
+CT_CONFIG_SHELL="${bash}"
+
+#
+# Logging
+#
+# CT_LOG_ERROR is not set
+# CT_LOG_WARN is not set
+CT_LOG_INFO=y
+# CT_LOG_EXTRA is not set
+# CT_LOG_ALL is not set
+# CT_LOG_DEBUG is not set
+CT_LOG_LEVEL_MAX="INFO"
+# CT_LOG_SEE_TOOLS_WARN is not set
+CT_LOG_PROGRESS_BAR=y
+CT_LOG_TO_FILE=y
+CT_LOG_FILE_COMPRESS=y
+
+#
+# Target options
+#
+CT_ARCH="arm"
+CT_ARCH_SUPPORTS_BOTH_MMU=y
+CT_ARCH_SUPPORTS_BOTH_ENDIAN=y
+CT_ARCH_SUPPORTS_32=y
+CT_ARCH_SUPPORTS_64=y
+CT_ARCH_SUPPORTS_WITH_ARCH=y
+CT_ARCH_SUPPORTS_WITH_CPU=y
+CT_ARCH_SUPPORTS_WITH_TUNE=y
+CT_ARCH_SUPPORTS_WITH_FLOAT=y
+CT_ARCH_SUPPORTS_WITH_FPU=y
+CT_ARCH_SUPPORTS_SOFTFP=y
+CT_ARCH_DEFAULT_HAS_MMU=y
+CT_ARCH_DEFAULT_LE=y
+CT_ARCH_DEFAULT_32=y
+CT_ARCH_ARCH="armv6"
+CT_ARCH_CPU=""
+CT_ARCH_TUNE=""
+CT_ARCH_FPU=""
+# CT_ARCH_BE is not set
+CT_ARCH_LE=y
+CT_ARCH_32=y
+# CT_ARCH_64 is not set
+CT_ARCH_BITNESS=32
+# CT_ARCH_FLOAT_HW is not set
+CT_ARCH_FLOAT_SW=y
+CT_TARGET_CFLAGS=""
+CT_TARGET_LDFLAGS=""
+# CT_ARCH_alpha is not set
+CT_ARCH_arm=y
+# CT_ARCH_avr is not set
+# CT_ARCH_m68k is not set
+# CT_ARCH_mips is not set
+# CT_ARCH_nios2 is not set
+# CT_ARCH_powerpc is not set
+# CT_ARCH_s390 is not set
+# CT_ARCH_sh is not set
+# CT_ARCH_sparc is not set
+# CT_ARCH_x86 is not set
+# CT_ARCH_xtensa is not set
+CT_ARCH_alpha_AVAILABLE=y
+CT_ARCH_arm_AVAILABLE=y
+CT_ARCH_avr_AVAILABLE=y
+CT_ARCH_m68k_AVAILABLE=y
+CT_ARCH_microblaze_AVAILABLE=y
+CT_ARCH_mips_AVAILABLE=y
+CT_ARCH_nios2_AVAILABLE=y
+CT_ARCH_powerpc_AVAILABLE=y
+CT_ARCH_s390_AVAILABLE=y
+CT_ARCH_sh_AVAILABLE=y
+CT_ARCH_sparc_AVAILABLE=y
+CT_ARCH_x86_AVAILABLE=y
+CT_ARCH_xtensa_AVAILABLE=y
+CT_ARCH_SUFFIX=""
+
+#
+# Generic target options
+#
+# CT_MULTILIB is not set
+CT_ARCH_USE_MMU=y
+CT_ARCH_ENDIAN="little"
+
+#
+# Target optimisations
+#
+CT_ARCH_EXCLUSIVE_WITH_CPU=y
+# CT_ARCH_FLOAT_AUTO is not set
+# CT_ARCH_FLOAT_SOFTFP is not set
+CT_ARCH_FLOAT="soft"
+
+#
+# arm other options
+#
+CT_ARCH_ARM_MODE="arm"
+CT_ARCH_ARM_MODE_ARM=y
+# CT_ARCH_ARM_MODE_THUMB is not set
+# CT_ARCH_ARM_INTERWORKING is not set
+CT_ARCH_ARM_EABI_FORCE=y
+CT_ARCH_ARM_EABI=y
+
+#
+# Toolchain options
+#
+
+#
+# General toolchain options
+#
+CT_FORCE_SYSROOT=y
+CT_USE_SYSROOT=y
+CT_SYSROOT_NAME="sysroot"
+CT_SYSROOT_DIR_PREFIX=""
+CT_WANTS_STATIC_LINK=y
+# CT_STATIC_TOOLCHAIN is not set
+CT_TOOLCHAIN_PKGVERSION=""
+CT_TOOLCHAIN_BUGURL=""
+
+#
+# Tuple completion and aliasing
+#
+CT_TARGET_VENDOR="unknown"
+CT_TARGET_ALIAS_SED_EXPR=""
+CT_TARGET_ALIAS=""
+
+#
+# Toolchain type
+#
+CT_CROSS=y
+# CT_CANADIAN is not set
+CT_TOOLCHAIN_TYPE="cross"
+
+#
+# Build system
+#
+CT_BUILD=""
+CT_BUILD_PREFIX=""
+CT_BUILD_SUFFIX=""
+
+#
+# Misc options
+#
+# CT_TOOLCHAIN_ENABLE_NLS is not set
+
+#
+# Operating System
+#
+CT_KERNEL_SUPPORTS_SHARED_LIBS=y
+CT_KERNEL="linux"
+CT_KERNEL_VERSION="3.2.72"
+# CT_KERNEL_bare_metal is not set
+CT_KERNEL_linux=y
+CT_KERNEL_bare_metal_AVAILABLE=y
+CT_KERNEL_linux_AVAILABLE=y
+# CT_KERNEL_V_4_3 is not set
+# CT_KERNEL_V_4_2 is not set
+# CT_KERNEL_V_4_1 is not set
+# CT_KERNEL_V_3_18 is not set
+# CT_KERNEL_V_3_14 is not set
+# CT_KERNEL_V_3_12 is not set
+# CT_KERNEL_V_3_10 is not set
+# CT_KERNEL_V_3_4 is not set
+CT_KERNEL_V_3_2=y
+# CT_KERNEL_V_2_6_32 is not set
+# CT_KERNEL_LINUX_CUSTOM is not set
+CT_KERNEL_windows_AVAILABLE=y
+
+#
+# Common kernel options
+#
+CT_SHARED_LIBS=y
+
+#
+# linux other options
+#
+CT_KERNEL_LINUX_VERBOSITY_0=y
+# CT_KERNEL_LINUX_VERBOSITY_1 is not set
+# CT_KERNEL_LINUX_VERBOSITY_2 is not set
+CT_KERNEL_LINUX_VERBOSE_LEVEL=0
+CT_KERNEL_LINUX_INSTALL_CHECK=y
+
+#
+# Binary utilities
+#
+CT_ARCH_BINFMT_ELF=y
+CT_BINUTILS="binutils"
+CT_BINUTILS_binutils=y
+
+#
+# GNU binutils
+#
+# CT_CC_BINUTILS_SHOW_LINARO is not set
+CT_BINUTILS_V_2_25_1=y
+# CT_BINUTILS_V_2_25 is not set
+# CT_BINUTILS_V_2_24 is not set
+# CT_BINUTILS_V_2_23_2 is not set
+# CT_BINUTILS_V_2_23_1 is not set
+# CT_BINUTILS_V_2_22 is not set
+# CT_BINUTILS_V_2_21_53 is not set
+# CT_BINUTILS_V_2_21_1a is not set
+# CT_BINUTILS_V_2_20_1a is not set
+# CT_BINUTILS_V_2_19_1a is not set
+# CT_BINUTILS_V_2_18a is not set
+CT_BINUTILS_VERSION="2.25.1"
+CT_BINUTILS_2_25_1_or_later=y
+CT_BINUTILS_2_25_or_later=y
+CT_BINUTILS_2_24_or_later=y
+CT_BINUTILS_2_23_or_later=y
+CT_BINUTILS_2_22_or_later=y
+CT_BINUTILS_2_21_or_later=y
+CT_BINUTILS_2_20_or_later=y
+CT_BINUTILS_2_19_or_later=y
+CT_BINUTILS_2_18_or_later=y
+CT_BINUTILS_HAS_HASH_STYLE=y
+CT_BINUTILS_HAS_GOLD=y
+CT_BINUTILS_GOLD_SUPPORTS_ARCH=y
+CT_BINUTILS_GOLD_SUPPORT=y
+CT_BINUTILS_HAS_PLUGINS=y
+CT_BINUTILS_HAS_PKGVERSION_BUGURL=y
+CT_BINUTILS_FORCE_LD_BFD=y
+CT_BINUTILS_LINKER_LD=y
+# CT_BINUTILS_LINKER_LD_GOLD is not set
+# CT_BINUTILS_LINKER_GOLD_LD is not set
+CT_BINUTILS_LINKERS_LIST="ld"
+CT_BINUTILS_LINKER_DEFAULT="bfd"
+# CT_BINUTILS_PLUGINS is not set
+CT_BINUTILS_EXTRA_CONFIG_ARRAY=""
+# CT_BINUTILS_FOR_TARGET is not set
+
+#
+# binutils other options
+#
+
+#
+# C-library
+#
+CT_LIBC="glibc"
+CT_LIBC_VERSION="2.16.0"
+CT_LIBC_glibc=y
+# CT_LIBC_musl is not set
+# CT_LIBC_uClibc is not set
+CT_LIBC_avr_libc_AVAILABLE=y
+CT_LIBC_glibc_AVAILABLE=y
+CT_THREADS="nptl"
+# CT_CC_GLIBC_SHOW_LINARO is not set
+# CT_LIBC_GLIBC_V_2_22 is not set
+# CT_LIBC_GLIBC_V_2_21 is not set
+# CT_LIBC_GLIBC_V_2_20 is not set
+# CT_LIBC_GLIBC_V_2_19 is not set
+# CT_LIBC_GLIBC_V_2_18 is not set
+# CT_LIBC_GLIBC_V_2_17 is not set
+CT_LIBC_GLIBC_V_2_16_0=y
+# CT_LIBC_GLIBC_V_2_15 is not set
+# CT_LIBC_GLIBC_V_2_14_1 is not set
+# CT_LIBC_GLIBC_V_2_14 is not set
+# CT_LIBC_GLIBC_V_2_13 is not set
+# CT_LIBC_GLIBC_V_2_12_2 is not set
+# CT_LIBC_GLIBC_V_2_12_1 is not set
+# CT_LIBC_GLIBC_V_2_11_1 is not set
+# CT_LIBC_GLIBC_V_2_11 is not set
+# CT_LIBC_GLIBC_V_2_10_1 is not set
+# CT_LIBC_GLIBC_V_2_9 is not set
+# CT_LIBC_GLIBC_V_2_8 is not set
+CT_LIBC_mingw_AVAILABLE=y
+CT_LIBC_musl_AVAILABLE=y
+CT_LIBC_newlib_AVAILABLE=y
+CT_LIBC_none_AVAILABLE=y
+CT_LIBC_uClibc_AVAILABLE=y
+CT_LIBC_SUPPORT_THREADS_ANY=y
+CT_LIBC_SUPPORT_THREADS_NATIVE=y
+
+#
+# Common C library options
+#
+CT_THREADS_NATIVE=y
+CT_LIBC_XLDD=y
+
+#
+# glibc other options
+#
+CT_LIBC_GLIBC_PORTS_EXTERNAL=y
+CT_LIBC_GLIBC_MAY_FORCE_PORTS=y
+CT_LIBC_glibc_familly=y
+CT_LIBC_GLIBC_EXTRA_CONFIG_ARRAY=""
+CT_LIBC_GLIBC_CONFIGPARMS=""
+CT_LIBC_GLIBC_EXTRA_CFLAGS=""
+CT_LIBC_EXTRA_CC_ARGS=""
+# CT_LIBC_DISABLE_VERSIONING is not set
+CT_LIBC_OLDEST_ABI=""
+CT_LIBC_GLIBC_FORCE_UNWIND=y
+CT_LIBC_GLIBC_USE_PORTS=y
+CT_LIBC_ADDONS_LIST=""
+
+#
+# WARNING !!!                                            
+#
+
+#
+#   For glibc >= 2.8, it can happen that the tarballs    
+#
+
+#
+#   for the addons are not available for download.       
+#
+
+#
+#   If that happens, bad luck... Try a previous version  
+#
+
+#
+#   or try again later... :-(                            
+#
+# CT_LIBC_LOCALES is not set
+# CT_LIBC_GLIBC_KERNEL_VERSION_NONE is not set
+CT_LIBC_GLIBC_KERNEL_VERSION_AS_HEADERS=y
+# CT_LIBC_GLIBC_KERNEL_VERSION_CHOSEN is not set
+CT_LIBC_GLIBC_MIN_KERNEL="3.2.72"
+
+#
+# C compiler
+#
+CT_CC="gcc"
+CT_CC_CORE_PASSES_NEEDED=y
+CT_CC_CORE_PASS_1_NEEDED=y
+CT_CC_CORE_PASS_2_NEEDED=y
+CT_CC_gcc=y
+# CT_CC_GCC_SHOW_LINARO is not set
+# CT_CC_GCC_V_5_2_0 is not set
+CT_CC_GCC_V_4_9_3=y
+# CT_CC_GCC_V_4_8_5 is not set
+# CT_CC_GCC_V_4_7_4 is not set
+# CT_CC_GCC_V_4_6_4 is not set
+# CT_CC_GCC_V_4_5_4 is not set
+# CT_CC_GCC_V_4_4_7 is not set
+# CT_CC_GCC_V_4_3_6 is not set
+# CT_CC_GCC_V_4_2_4 is not set
+CT_CC_GCC_4_2_or_later=y
+CT_CC_GCC_4_3_or_later=y
+CT_CC_GCC_4_4_or_later=y
+CT_CC_GCC_4_5_or_later=y
+CT_CC_GCC_4_6_or_later=y
+CT_CC_GCC_4_7_or_later=y
+CT_CC_GCC_4_8_or_later=y
+CT_CC_GCC_4_9=y
+CT_CC_GCC_4_9_or_later=y
+CT_CC_GCC_HAS_GRAPHITE=y
+CT_CC_GCC_USE_GRAPHITE=y
+CT_CC_GCC_HAS_LTO=y
+CT_CC_GCC_USE_LTO=y
+CT_CC_GCC_HAS_PKGVERSION_BUGURL=y
+CT_CC_GCC_HAS_BUILD_ID=y
+CT_CC_GCC_HAS_LNK_HASH_STYLE=y
+CT_CC_GCC_USE_GMP_MPFR=y
+CT_CC_GCC_USE_MPC=y
+CT_CC_GCC_HAS_LIBQUADMATH=y
+CT_CC_GCC_HAS_LIBSANITIZER=y
+CT_CC_GCC_VERSION="4.9.3"
+# CT_CC_LANG_FORTRAN is not set
+CT_CC_GCC_ENABLE_CXX_FLAGS=""
+CT_CC_GCC_CORE_EXTRA_CONFIG_ARRAY=""
+CT_CC_GCC_EXTRA_CONFIG_ARRAY=""
+CT_CC_GCC_EXTRA_ENV_ARRAY=""
+CT_CC_GCC_STATIC_LIBSTDCXX=y
+# CT_CC_GCC_SYSTEM_ZLIB is not set
+
+#
+# Optimisation features
+#
+
+#
+# Settings for libraries running on target
+#
+CT_CC_GCC_ENABLE_TARGET_OPTSPACE=y
+# CT_CC_GCC_LIBMUDFLAP is not set
+# CT_CC_GCC_LIBGOMP is not set
+# CT_CC_GCC_LIBSSP is not set
+# CT_CC_GCC_LIBQUADMATH is not set
+# CT_CC_GCC_LIBSANITIZER is not set
+
+#
+# Misc. obscure options.
+#
+CT_CC_CXA_ATEXIT=y
+# CT_CC_GCC_DISABLE_PCH is not set
+CT_CC_GCC_SJLJ_EXCEPTIONS=m
+CT_CC_GCC_LDBL_128=m
+# CT_CC_GCC_BUILD_ID is not set
+CT_CC_GCC_LNK_HASH_STYLE_DEFAULT=y
+# CT_CC_GCC_LNK_HASH_STYLE_SYSV is not set
+# CT_CC_GCC_LNK_HASH_STYLE_GNU is not set
+# CT_CC_GCC_LNK_HASH_STYLE_BOTH is not set
+CT_CC_GCC_LNK_HASH_STYLE=""
+CT_CC_GCC_DEC_FLOAT_AUTO=y
+# CT_CC_GCC_DEC_FLOAT_BID is not set
+# CT_CC_GCC_DEC_FLOAT_DPD is not set
+# CT_CC_GCC_DEC_FLOATS_NO is not set
+CT_CC_SUPPORT_CXX=y
+CT_CC_SUPPORT_FORTRAN=y
+CT_CC_SUPPORT_JAVA=y
+CT_CC_SUPPORT_ADA=y
+CT_CC_SUPPORT_OBJC=y
+CT_CC_SUPPORT_OBJCXX=y
+CT_CC_SUPPORT_GOLANG=y
+
+#
+# Additional supported languages:
+#
+CT_CC_LANG_CXX=y
+# CT_CC_LANG_JAVA is not set
+
+#
+# Debug facilities
+#
+# CT_DEBUG_dmalloc is not set
+# CT_DEBUG_duma is not set
+# CT_DEBUG_gdb is not set
+# CT_DEBUG_ltrace is not set
+# CT_DEBUG_strace is not set
+
+#
+# Companion libraries
+#
+CT_COMPLIBS_NEEDED=y
+CT_LIBICONV_NEEDED=y
+CT_GETTEXT_NEEDED=y
+CT_GMP_NEEDED=y
+CT_MPFR_NEEDED=y
+CT_ISL_NEEDED=y
+CT_CLOOG_NEEDED=y
+CT_MPC_NEEDED=y
+CT_COMPLIBS=y
+CT_LIBICONV=y
+CT_GETTEXT=y
+CT_GMP=y
+CT_MPFR=y
+CT_ISL=y
+CT_CLOOG=y
+CT_MPC=y
+CT_LIBICONV_V_1_14=y
+CT_LIBICONV_VERSION="1.14"
+CT_GETTEXT_V_0_19_6=y
+CT_GETTEXT_VERSION="0.19.6"
+CT_GMP_V_6_0_0=y
+# CT_GMP_V_5_1_3 is not set
+# CT_GMP_V_5_1_1 is not set
+# CT_GMP_V_5_0_2 is not set
+# CT_GMP_V_5_0_1 is not set
+# CT_GMP_V_4_3_2 is not set
+# CT_GMP_V_4_3_1 is not set
+# CT_GMP_V_4_3_0 is not set
+CT_GMP_5_0_2_or_later=y
+CT_GMP_VERSION="6.0.0a"
+CT_MPFR_V_3_1_3=y
+# CT_MPFR_V_3_1_2 is not set
+# CT_MPFR_V_3_1_0 is not set
+# CT_MPFR_V_3_0_1 is not set
+# CT_MPFR_V_3_0_0 is not set
+# CT_MPFR_V_2_4_2 is not set
+# CT_MPFR_V_2_4_1 is not set
+# CT_MPFR_V_2_4_0 is not set
+CT_MPFR_VERSION="3.1.3"
+CT_ISL_V_0_14=y
+CT_ISL_V_0_14_or_later=y
+CT_ISL_V_0_12_or_later=y
+CT_ISL_VERSION="0.14"
+CT_CLOOG_V_0_18_4=y
+# CT_CLOOG_V_0_18_1 is not set
+# CT_CLOOG_V_0_18_0 is not set
+CT_CLOOG_VERSION="0.18.4"
+CT_CLOOG_0_18_4_or_later=y
+CT_CLOOG_0_18_or_later=y
+CT_MPC_V_1_0_3=y
+# CT_MPC_V_1_0_2 is not set
+# CT_MPC_V_1_0_1 is not set
+# CT_MPC_V_1_0 is not set
+# CT_MPC_V_0_9 is not set
+# CT_MPC_V_0_8_2 is not set
+# CT_MPC_V_0_8_1 is not set
+# CT_MPC_V_0_7 is not set
+CT_MPC_VERSION="1.0.3"
+
+#
+# Companion libraries common options
+#
+# CT_COMPLIBS_CHECK is not set
+
+#
+# Companion tools
+#
+
+#
+# READ HELP before you say 'Y' below !!!
+#
+# CT_COMP_TOOLS is not set
diff --git a/src/ci/docker/dist-arm-linux/arm-linux-gnueabihf.config b/src/ci/docker/dist-arm-linux/arm-linux-gnueabihf.config
new file mode 100644
index 0000000000000..1feeef1555749
--- /dev/null
+++ b/src/ci/docker/dist-arm-linux/arm-linux-gnueabihf.config
@@ -0,0 +1,561 @@
+#
+# Automatically generated file; DO NOT EDIT.
+# Crosstool-NG Configuration
+#
+CT_CONFIGURE_has_make381=y
+CT_MODULES=y
+
+#
+# Paths and misc options
+#
+
+#
+# crosstool-NG behavior
+#
+# CT_OBSOLETE is not set
+# CT_EXPERIMENTAL is not set
+# CT_DEBUG_CT is not set
+
+#
+# Paths
+#
+CT_LOCAL_TARBALLS_DIR=""
+CT_WORK_DIR="${CT_TOP_DIR}/.build"
+CT_PREFIX_DIR="/x-tools/${CT_TARGET}"
+CT_INSTALL_DIR="${CT_PREFIX_DIR}"
+CT_RM_RF_PREFIX_DIR=y
+CT_REMOVE_DOCS=y
+CT_INSTALL_DIR_RO=y
+CT_STRIP_HOST_TOOLCHAIN_EXECUTABLES=y
+# CT_STRIP_TARGET_TOOLCHAIN_EXECUTABLES is not set
+
+#
+# Downloading
+#
+# CT_FORBID_DOWNLOAD is not set
+# CT_FORCE_DOWNLOAD is not set
+CT_CONNECT_TIMEOUT=10
+# CT_ONLY_DOWNLOAD is not set
+# CT_USE_MIRROR is not set
+
+#
+# Extracting
+#
+# CT_FORCE_EXTRACT is not set
+CT_OVERIDE_CONFIG_GUESS_SUB=y
+# CT_ONLY_EXTRACT is not set
+CT_PATCH_BUNDLED=y
+# CT_PATCH_LOCAL is not set
+# CT_PATCH_BUNDLED_LOCAL is not set
+# CT_PATCH_LOCAL_BUNDLED is not set
+# CT_PATCH_BUNDLED_FALLBACK_LOCAL is not set
+# CT_PATCH_LOCAL_FALLBACK_BUNDLED is not set
+# CT_PATCH_NONE is not set
+CT_PATCH_ORDER="bundled"
+
+#
+# Build behavior
+#
+CT_PARALLEL_JOBS=0
+CT_LOAD=""
+CT_USE_PIPES=y
+CT_EXTRA_CFLAGS_FOR_BUILD=""
+CT_EXTRA_LDFLAGS_FOR_BUILD=""
+CT_EXTRA_CFLAGS_FOR_HOST=""
+CT_EXTRA_LDFLAGS_FOR_HOST=""
+# CT_CONFIG_SHELL_SH is not set
+# CT_CONFIG_SHELL_ASH is not set
+CT_CONFIG_SHELL_BASH=y
+# CT_CONFIG_SHELL_CUSTOM is not set
+CT_CONFIG_SHELL="${bash}"
+
+#
+# Logging
+#
+# CT_LOG_ERROR is not set
+# CT_LOG_WARN is not set
+CT_LOG_INFO=y
+# CT_LOG_EXTRA is not set
+# CT_LOG_ALL is not set
+# CT_LOG_DEBUG is not set
+CT_LOG_LEVEL_MAX="INFO"
+# CT_LOG_SEE_TOOLS_WARN is not set
+CT_LOG_PROGRESS_BAR=y
+CT_LOG_TO_FILE=y
+CT_LOG_FILE_COMPRESS=y
+
+#
+# Target options
+#
+CT_ARCH="arm"
+CT_ARCH_SUPPORTS_BOTH_MMU=y
+CT_ARCH_SUPPORTS_BOTH_ENDIAN=y
+CT_ARCH_SUPPORTS_32=y
+CT_ARCH_SUPPORTS_64=y
+CT_ARCH_SUPPORTS_WITH_ARCH=y
+CT_ARCH_SUPPORTS_WITH_CPU=y
+CT_ARCH_SUPPORTS_WITH_TUNE=y
+CT_ARCH_SUPPORTS_WITH_FLOAT=y
+CT_ARCH_SUPPORTS_WITH_FPU=y
+CT_ARCH_SUPPORTS_SOFTFP=y
+CT_ARCH_DEFAULT_HAS_MMU=y
+CT_ARCH_DEFAULT_LE=y
+CT_ARCH_DEFAULT_32=y
+CT_ARCH_ARCH="armv6"
+CT_ARCH_CPU=""
+CT_ARCH_TUNE=""
+CT_ARCH_FPU="vfp"
+# CT_ARCH_BE is not set
+CT_ARCH_LE=y
+CT_ARCH_32=y
+# CT_ARCH_64 is not set
+CT_ARCH_BITNESS=32
+CT_ARCH_FLOAT_HW=y
+# CT_ARCH_FLOAT_SW is not set
+CT_TARGET_CFLAGS=""
+CT_TARGET_LDFLAGS=""
+# CT_ARCH_alpha is not set
+CT_ARCH_arm=y
+# CT_ARCH_avr is not set
+# CT_ARCH_m68k is not set
+# CT_ARCH_mips is not set
+# CT_ARCH_nios2 is not set
+# CT_ARCH_powerpc is not set
+# CT_ARCH_s390 is not set
+# CT_ARCH_sh is not set
+# CT_ARCH_sparc is not set
+# CT_ARCH_x86 is not set
+# CT_ARCH_xtensa is not set
+CT_ARCH_alpha_AVAILABLE=y
+CT_ARCH_arm_AVAILABLE=y
+CT_ARCH_avr_AVAILABLE=y
+CT_ARCH_m68k_AVAILABLE=y
+CT_ARCH_microblaze_AVAILABLE=y
+CT_ARCH_mips_AVAILABLE=y
+CT_ARCH_nios2_AVAILABLE=y
+CT_ARCH_powerpc_AVAILABLE=y
+CT_ARCH_s390_AVAILABLE=y
+CT_ARCH_sh_AVAILABLE=y
+CT_ARCH_sparc_AVAILABLE=y
+CT_ARCH_x86_AVAILABLE=y
+CT_ARCH_xtensa_AVAILABLE=y
+CT_ARCH_SUFFIX=""
+
+#
+# Generic target options
+#
+# CT_MULTILIB is not set
+CT_ARCH_USE_MMU=y
+CT_ARCH_ENDIAN="little"
+
+#
+# Target optimisations
+#
+CT_ARCH_EXCLUSIVE_WITH_CPU=y
+# CT_ARCH_FLOAT_AUTO is not set
+# CT_ARCH_FLOAT_SOFTFP is not set
+CT_ARCH_FLOAT="hard"
+
+#
+# arm other options
+#
+CT_ARCH_ARM_MODE="arm"
+CT_ARCH_ARM_MODE_ARM=y
+# CT_ARCH_ARM_MODE_THUMB is not set
+# CT_ARCH_ARM_INTERWORKING is not set
+CT_ARCH_ARM_EABI_FORCE=y
+CT_ARCH_ARM_EABI=y
+CT_ARCH_ARM_TUPLE_USE_EABIHF=y
+
+#
+# Toolchain options
+#
+
+#
+# General toolchain options
+#
+CT_FORCE_SYSROOT=y
+CT_USE_SYSROOT=y
+CT_SYSROOT_NAME="sysroot"
+CT_SYSROOT_DIR_PREFIX=""
+CT_WANTS_STATIC_LINK=y
+# CT_STATIC_TOOLCHAIN is not set
+CT_TOOLCHAIN_PKGVERSION=""
+CT_TOOLCHAIN_BUGURL=""
+
+#
+# Tuple completion and aliasing
+#
+CT_TARGET_VENDOR="unknown"
+CT_TARGET_ALIAS_SED_EXPR=""
+CT_TARGET_ALIAS=""
+
+#
+# Toolchain type
+#
+CT_CROSS=y
+# CT_CANADIAN is not set
+CT_TOOLCHAIN_TYPE="cross"
+
+#
+# Build system
+#
+CT_BUILD=""
+CT_BUILD_PREFIX=""
+CT_BUILD_SUFFIX=""
+
+#
+# Misc options
+#
+# CT_TOOLCHAIN_ENABLE_NLS is not set
+
+#
+# Operating System
+#
+CT_KERNEL_SUPPORTS_SHARED_LIBS=y
+CT_KERNEL="linux"
+CT_KERNEL_VERSION="3.2.72"
+# CT_KERNEL_bare_metal is not set
+CT_KERNEL_linux=y
+CT_KERNEL_bare_metal_AVAILABLE=y
+CT_KERNEL_linux_AVAILABLE=y
+# CT_KERNEL_V_4_3 is not set
+# CT_KERNEL_V_4_2 is not set
+# CT_KERNEL_V_4_1 is not set
+# CT_KERNEL_V_3_18 is not set
+# CT_KERNEL_V_3_14 is not set
+# CT_KERNEL_V_3_12 is not set
+# CT_KERNEL_V_3_10 is not set
+# CT_KERNEL_V_3_4 is not set
+CT_KERNEL_V_3_2=y
+# CT_KERNEL_V_2_6_32 is not set
+# CT_KERNEL_LINUX_CUSTOM is not set
+CT_KERNEL_windows_AVAILABLE=y
+
+#
+# Common kernel options
+#
+CT_SHARED_LIBS=y
+
+#
+# linux other options
+#
+CT_KERNEL_LINUX_VERBOSITY_0=y
+# CT_KERNEL_LINUX_VERBOSITY_1 is not set
+# CT_KERNEL_LINUX_VERBOSITY_2 is not set
+CT_KERNEL_LINUX_VERBOSE_LEVEL=0
+CT_KERNEL_LINUX_INSTALL_CHECK=y
+
+#
+# Binary utilities
+#
+CT_ARCH_BINFMT_ELF=y
+CT_BINUTILS="binutils"
+CT_BINUTILS_binutils=y
+
+#
+# GNU binutils
+#
+# CT_CC_BINUTILS_SHOW_LINARO is not set
+CT_BINUTILS_V_2_25_1=y
+# CT_BINUTILS_V_2_25 is not set
+# CT_BINUTILS_V_2_24 is not set
+# CT_BINUTILS_V_2_23_2 is not set
+# CT_BINUTILS_V_2_23_1 is not set
+# CT_BINUTILS_V_2_22 is not set
+# CT_BINUTILS_V_2_21_53 is not set
+# CT_BINUTILS_V_2_21_1a is not set
+# CT_BINUTILS_V_2_20_1a is not set
+# CT_BINUTILS_V_2_19_1a is not set
+# CT_BINUTILS_V_2_18a is not set
+CT_BINUTILS_VERSION="2.25.1"
+CT_BINUTILS_2_25_1_or_later=y
+CT_BINUTILS_2_25_or_later=y
+CT_BINUTILS_2_24_or_later=y
+CT_BINUTILS_2_23_or_later=y
+CT_BINUTILS_2_22_or_later=y
+CT_BINUTILS_2_21_or_later=y
+CT_BINUTILS_2_20_or_later=y
+CT_BINUTILS_2_19_or_later=y
+CT_BINUTILS_2_18_or_later=y
+CT_BINUTILS_HAS_HASH_STYLE=y
+CT_BINUTILS_HAS_GOLD=y
+CT_BINUTILS_GOLD_SUPPORTS_ARCH=y
+CT_BINUTILS_GOLD_SUPPORT=y
+CT_BINUTILS_HAS_PLUGINS=y
+CT_BINUTILS_HAS_PKGVERSION_BUGURL=y
+CT_BINUTILS_FORCE_LD_BFD=y
+CT_BINUTILS_LINKER_LD=y
+# CT_BINUTILS_LINKER_LD_GOLD is not set
+# CT_BINUTILS_LINKER_GOLD_LD is not set
+CT_BINUTILS_LINKERS_LIST="ld"
+CT_BINUTILS_LINKER_DEFAULT="bfd"
+# CT_BINUTILS_PLUGINS is not set
+CT_BINUTILS_EXTRA_CONFIG_ARRAY=""
+# CT_BINUTILS_FOR_TARGET is not set
+
+#
+# binutils other options
+#
+
+#
+# C-library
+#
+CT_LIBC="glibc"
+CT_LIBC_VERSION="2.16.0"
+CT_LIBC_glibc=y
+# CT_LIBC_musl is not set
+# CT_LIBC_uClibc is not set
+CT_LIBC_avr_libc_AVAILABLE=y
+CT_LIBC_glibc_AVAILABLE=y
+CT_THREADS="nptl"
+# CT_CC_GLIBC_SHOW_LINARO is not set
+# CT_LIBC_GLIBC_V_2_22 is not set
+# CT_LIBC_GLIBC_V_2_21 is not set
+# CT_LIBC_GLIBC_V_2_20 is not set
+# CT_LIBC_GLIBC_V_2_19 is not set
+# CT_LIBC_GLIBC_V_2_18 is not set
+# CT_LIBC_GLIBC_V_2_17 is not set
+CT_LIBC_GLIBC_V_2_16_0=y
+# CT_LIBC_GLIBC_V_2_15 is not set
+# CT_LIBC_GLIBC_V_2_14_1 is not set
+# CT_LIBC_GLIBC_V_2_14 is not set
+# CT_LIBC_GLIBC_V_2_13 is not set
+# CT_LIBC_GLIBC_V_2_12_2 is not set
+# CT_LIBC_GLIBC_V_2_12_1 is not set
+# CT_LIBC_GLIBC_V_2_11_1 is not set
+# CT_LIBC_GLIBC_V_2_11 is not set
+# CT_LIBC_GLIBC_V_2_10_1 is not set
+# CT_LIBC_GLIBC_V_2_9 is not set
+# CT_LIBC_GLIBC_V_2_8 is not set
+CT_LIBC_mingw_AVAILABLE=y
+CT_LIBC_musl_AVAILABLE=y
+CT_LIBC_newlib_AVAILABLE=y
+CT_LIBC_none_AVAILABLE=y
+CT_LIBC_uClibc_AVAILABLE=y
+CT_LIBC_SUPPORT_THREADS_ANY=y
+CT_LIBC_SUPPORT_THREADS_NATIVE=y
+
+#
+# Common C library options
+#
+CT_THREADS_NATIVE=y
+CT_LIBC_XLDD=y
+
+#
+# glibc other options
+#
+CT_LIBC_GLIBC_PORTS_EXTERNAL=y
+CT_LIBC_GLIBC_MAY_FORCE_PORTS=y
+CT_LIBC_glibc_familly=y
+CT_LIBC_GLIBC_EXTRA_CONFIG_ARRAY=""
+CT_LIBC_GLIBC_CONFIGPARMS=""
+CT_LIBC_GLIBC_EXTRA_CFLAGS=""
+CT_LIBC_EXTRA_CC_ARGS=""
+# CT_LIBC_DISABLE_VERSIONING is not set
+CT_LIBC_OLDEST_ABI=""
+CT_LIBC_GLIBC_FORCE_UNWIND=y
+CT_LIBC_GLIBC_USE_PORTS=y
+CT_LIBC_ADDONS_LIST=""
+
+#
+# WARNING !!!                                            
+#
+
+#
+#   For glibc >= 2.8, it can happen that the tarballs    
+#
+
+#
+#   for the addons are not available for download.       
+#
+
+#
+#   If that happens, bad luck... Try a previous version  
+#
+
+#
+#   or try again later... :-(                            
+#
+# CT_LIBC_LOCALES is not set
+# CT_LIBC_GLIBC_KERNEL_VERSION_NONE is not set
+CT_LIBC_GLIBC_KERNEL_VERSION_AS_HEADERS=y
+# CT_LIBC_GLIBC_KERNEL_VERSION_CHOSEN is not set
+CT_LIBC_GLIBC_MIN_KERNEL="3.2.72"
+
+#
+# C compiler
+#
+CT_CC="gcc"
+CT_CC_CORE_PASSES_NEEDED=y
+CT_CC_CORE_PASS_1_NEEDED=y
+CT_CC_CORE_PASS_2_NEEDED=y
+CT_CC_gcc=y
+# CT_CC_GCC_SHOW_LINARO is not set
+# CT_CC_GCC_V_5_2_0 is not set
+CT_CC_GCC_V_4_9_3=y
+# CT_CC_GCC_V_4_8_5 is not set
+# CT_CC_GCC_V_4_7_4 is not set
+# CT_CC_GCC_V_4_6_4 is not set
+# CT_CC_GCC_V_4_5_4 is not set
+# CT_CC_GCC_V_4_4_7 is not set
+# CT_CC_GCC_V_4_3_6 is not set
+# CT_CC_GCC_V_4_2_4 is not set
+CT_CC_GCC_4_2_or_later=y
+CT_CC_GCC_4_3_or_later=y
+CT_CC_GCC_4_4_or_later=y
+CT_CC_GCC_4_5_or_later=y
+CT_CC_GCC_4_6_or_later=y
+CT_CC_GCC_4_7_or_later=y
+CT_CC_GCC_4_8_or_later=y
+CT_CC_GCC_4_9=y
+CT_CC_GCC_4_9_or_later=y
+CT_CC_GCC_HAS_GRAPHITE=y
+CT_CC_GCC_USE_GRAPHITE=y
+CT_CC_GCC_HAS_LTO=y
+CT_CC_GCC_USE_LTO=y
+CT_CC_GCC_HAS_PKGVERSION_BUGURL=y
+CT_CC_GCC_HAS_BUILD_ID=y
+CT_CC_GCC_HAS_LNK_HASH_STYLE=y
+CT_CC_GCC_USE_GMP_MPFR=y
+CT_CC_GCC_USE_MPC=y
+CT_CC_GCC_HAS_LIBQUADMATH=y
+CT_CC_GCC_HAS_LIBSANITIZER=y
+CT_CC_GCC_VERSION="4.9.3"
+# CT_CC_LANG_FORTRAN is not set
+CT_CC_GCC_ENABLE_CXX_FLAGS=""
+CT_CC_GCC_CORE_EXTRA_CONFIG_ARRAY=""
+CT_CC_GCC_EXTRA_CONFIG_ARRAY=""
+CT_CC_GCC_EXTRA_ENV_ARRAY=""
+CT_CC_GCC_STATIC_LIBSTDCXX=y
+# CT_CC_GCC_SYSTEM_ZLIB is not set
+
+#
+# Optimisation features
+#
+
+#
+# Settings for libraries running on target
+#
+CT_CC_GCC_ENABLE_TARGET_OPTSPACE=y
+# CT_CC_GCC_LIBMUDFLAP is not set
+# CT_CC_GCC_LIBGOMP is not set
+# CT_CC_GCC_LIBSSP is not set
+# CT_CC_GCC_LIBQUADMATH is not set
+# CT_CC_GCC_LIBSANITIZER is not set
+
+#
+# Misc. obscure options.
+#
+CT_CC_CXA_ATEXIT=y
+# CT_CC_GCC_DISABLE_PCH is not set
+CT_CC_GCC_SJLJ_EXCEPTIONS=m
+CT_CC_GCC_LDBL_128=m
+# CT_CC_GCC_BUILD_ID is not set
+CT_CC_GCC_LNK_HASH_STYLE_DEFAULT=y
+# CT_CC_GCC_LNK_HASH_STYLE_SYSV is not set
+# CT_CC_GCC_LNK_HASH_STYLE_GNU is not set
+# CT_CC_GCC_LNK_HASH_STYLE_BOTH is not set
+CT_CC_GCC_LNK_HASH_STYLE=""
+CT_CC_GCC_DEC_FLOAT_AUTO=y
+# CT_CC_GCC_DEC_FLOAT_BID is not set
+# CT_CC_GCC_DEC_FLOAT_DPD is not set
+# CT_CC_GCC_DEC_FLOATS_NO is not set
+CT_CC_SUPPORT_CXX=y
+CT_CC_SUPPORT_FORTRAN=y
+CT_CC_SUPPORT_JAVA=y
+CT_CC_SUPPORT_ADA=y
+CT_CC_SUPPORT_OBJC=y
+CT_CC_SUPPORT_OBJCXX=y
+CT_CC_SUPPORT_GOLANG=y
+
+#
+# Additional supported languages:
+#
+CT_CC_LANG_CXX=y
+# CT_CC_LANG_JAVA is not set
+
+#
+# Debug facilities
+#
+# CT_DEBUG_dmalloc is not set
+# CT_DEBUG_duma is not set
+# CT_DEBUG_gdb is not set
+# CT_DEBUG_ltrace is not set
+# CT_DEBUG_strace is not set
+
+#
+# Companion libraries
+#
+CT_COMPLIBS_NEEDED=y
+CT_LIBICONV_NEEDED=y
+CT_GETTEXT_NEEDED=y
+CT_GMP_NEEDED=y
+CT_MPFR_NEEDED=y
+CT_ISL_NEEDED=y
+CT_CLOOG_NEEDED=y
+CT_MPC_NEEDED=y
+CT_COMPLIBS=y
+CT_LIBICONV=y
+CT_GETTEXT=y
+CT_GMP=y
+CT_MPFR=y
+CT_ISL=y
+CT_CLOOG=y
+CT_MPC=y
+CT_LIBICONV_V_1_14=y
+CT_LIBICONV_VERSION="1.14"
+CT_GETTEXT_V_0_19_6=y
+CT_GETTEXT_VERSION="0.19.6"
+CT_GMP_V_6_0_0=y
+# CT_GMP_V_5_1_3 is not set
+# CT_GMP_V_5_1_1 is not set
+# CT_GMP_V_5_0_2 is not set
+# CT_GMP_V_5_0_1 is not set
+# CT_GMP_V_4_3_2 is not set
+# CT_GMP_V_4_3_1 is not set
+# CT_GMP_V_4_3_0 is not set
+CT_GMP_5_0_2_or_later=y
+CT_GMP_VERSION="6.0.0a"
+CT_MPFR_V_3_1_3=y
+# CT_MPFR_V_3_1_2 is not set
+# CT_MPFR_V_3_1_0 is not set
+# CT_MPFR_V_3_0_1 is not set
+# CT_MPFR_V_3_0_0 is not set
+# CT_MPFR_V_2_4_2 is not set
+# CT_MPFR_V_2_4_1 is not set
+# CT_MPFR_V_2_4_0 is not set
+CT_MPFR_VERSION="3.1.3"
+CT_ISL_V_0_14=y
+CT_ISL_V_0_14_or_later=y
+CT_ISL_V_0_12_or_later=y
+CT_ISL_VERSION="0.14"
+CT_CLOOG_V_0_18_4=y
+# CT_CLOOG_V_0_18_1 is not set
+# CT_CLOOG_V_0_18_0 is not set
+CT_CLOOG_VERSION="0.18.4"
+CT_CLOOG_0_18_4_or_later=y
+CT_CLOOG_0_18_or_later=y
+CT_MPC_V_1_0_3=y
+# CT_MPC_V_1_0_2 is not set
+# CT_MPC_V_1_0_1 is not set
+# CT_MPC_V_1_0 is not set
+# CT_MPC_V_0_9 is not set
+# CT_MPC_V_0_8_2 is not set
+# CT_MPC_V_0_8_1 is not set
+# CT_MPC_V_0_7 is not set
+CT_MPC_VERSION="1.0.3"
+
+#
+# Companion libraries common options
+#
+# CT_COMPLIBS_CHECK is not set
+
+#
+# Companion tools
+#
+
+#
+# READ HELP before you say 'Y' below !!!
+#
+# CT_COMP_TOOLS is not set
diff --git a/src/ci/docker/dist-arm-linux/build-toolchains.sh b/src/ci/docker/dist-arm-linux/build-toolchains.sh
new file mode 100755
index 0000000000000..ed1406bd7cfa7
--- /dev/null
+++ b/src/ci/docker/dist-arm-linux/build-toolchains.sh
@@ -0,0 +1,45 @@
+#!/bin/bash
+# Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+# file at the top-level directory of this distribution and at
+# http://rust-lang.org/COPYRIGHT.
+#
+# Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+# http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+# <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+# option. This file may not be copied, modified, or distributed
+# except according to those terms.
+
+set -ex
+
+hide_output() {
+  set +x
+  on_err="
+echo ERROR: An error was encountered with the build.
+cat /tmp/build.log
+exit 1
+"
+  trap "$on_err" ERR
+  bash -c "while true; do sleep 30; echo \$(date) - building ...; done" &
+  PING_LOOP_PID=$!
+  $@ &> /tmp/build.log
+  rm /tmp/build.log
+  trap - ERR
+  kill $PING_LOOP_PID
+  set -x
+}
+
+mkdir build
+cd build
+cp ../arm-linux-gnueabi.config .config
+ct-ng oldconfig
+hide_output ct-ng build
+cd ..
+rm -rf build
+
+mkdir build
+cd build
+cp ../arm-linux-gnueabihf.config .config
+ct-ng oldconfig
+hide_output ct-ng build
+cd ..
+rm -rf build
diff --git a/src/ci/docker/dist-armv7-aarch64-linux/Dockerfile b/src/ci/docker/dist-armv7-aarch64-linux/Dockerfile
index 134e2b062ef0b..93d9e004c8c2d 100644
--- a/src/ci/docker/dist-armv7-aarch64-linux/Dockerfile
+++ b/src/ci/docker/dist-armv7-aarch64-linux/Dockerfile
@@ -1,19 +1,29 @@
 FROM ubuntu:16.04
 
 RUN apt-get update && apt-get install -y --no-install-recommends \
+  automake \
+  bison \
+  bzip2 \
+  ca-certificates \
+  cmake \
+  curl \
+  file \
+  flex \
   g++ \
+  gawk \
+  gdb \
+  git \
+  gperf \
+  help2man \
+  libncurses-dev \
+  libtool-bin \
   make \
-  file \
-  curl \
-  ca-certificates \
+  patch \
   python2.7 \
-  git \
-  cmake \
   sudo \
-  gdb \
-  xz-utils \
-  g++-arm-linux-gnueabihf \
-  g++-aarch64-linux-gnu
+  texinfo \
+  wget \
+  xz-utils
 
 ENV SCCACHE_DIGEST=7237e38e029342fa27b7ac25412cb9d52554008b12389727320bd533fd7f05b6a96d55485f305caf95e5c8f5f97c3313e10012ccad3e752aba2518f3522ba783
 RUN curl -L https://api.pub.build.mozilla.org/tooltool/sha512/$SCCACHE_DIGEST | \
@@ -24,11 +34,48 @@ RUN curl -OL https://github.com/Yelp/dumb-init/releases/download/v1.2.0/dumb-ini
     rm dumb-init_*.deb
 ENTRYPOINT ["/usr/bin/dumb-init", "--"]
 
-ENV RUST_CONFIGURE_ARGS \
-      --host=armv7-unknown-linux-gnueabihf,aarch64-unknown-linux-gnu
-ENV SCRIPT \
-      python2.7 ../x.py dist \
-        --host armv7-unknown-linux-gnueabihf \
-        --target armv7-unknown-linux-gnueabihf \
-        --host aarch64-unknown-linux-gnu \
-        --target aarch64-unknown-linux-gnu
+# Ubuntu 16.04 (this contianer) ships with make 4, but something in the
+# toolchains we build below chokes on that, so go back to make 3
+RUN curl https://ftp.gnu.org/gnu/make/make-3.81.tar.gz | tar xzf - && \
+      cd make-3.81 && \
+      ./configure --prefix=/usr && \
+      make && \
+      make install && \
+      cd .. && \
+      rm -rf make-3.81
+
+RUN curl http://crosstool-ng.org/download/crosstool-ng/crosstool-ng-1.22.0.tar.bz2 | \
+      tar xjf - && \
+      cd crosstool-ng && \
+      ./configure --prefix=/usr/local && \
+      make -j$(nproc) && \
+      make install && \
+      cd .. && \
+      rm -rf crosstool-ng
+
+RUN groupadd -r rustbuild && useradd -m -r -g rustbuild rustbuild
+RUN mkdir /x-tools && chown rustbuild:rustbuild /x-tools
+USER rustbuild
+WORKDIR /tmp
+
+COPY armv7-linux-gnueabihf.config /tmp/
+COPY armv7-linux-gnueabihf.config aarch64-linux-gnu.config build-toolchains.sh /tmp/
+RUN ./build-toolchains.sh
+
+USER root
+
+ENV PATH=$PATH:/x-tools/aarch64-unknown-linux-gnueabi/bin
+ENV PATH=$PATH:/x-tools/armv7-unknown-linux-gnueabihf/bin
+
+ENV CC_aarch64_unknown_linux_gnu=aarch64-unknown-linux-gnueabi-gcc \
+    AR_aarch64_unknown_linux_gnu=aarch64-unknown-linux-gnueabi-ar \
+    CXX_aarch64_unknown_linux_gnu=aarch64-unknown-linux-gnueabi-g++ \
+    CC_armv7_unknown_linux_gnueabihf=armv7-unknown-linux-gnueabihf-gcc \
+    AR_armv7_unknown_linux_gnueabihf=armv7-unknown-linux-gnueabihf-ar \
+    CXX_armv7_unknown_linux_gnueabihf=armv7-unknown-linux-gnueabihf-g++
+
+ENV HOSTS=armv7-unknown-linux-gnueabihf
+ENV HOSTS=$HOSTS,aarch64-unknown-linux-gnu
+
+ENV RUST_CONFIGURE_ARGS --host=$HOSTS
+ENV SCRIPT python2.7 ../x.py dist --host $HOSTS --target $HOSTS
diff --git a/src/ci/docker/dist-armv7-aarch64-linux/aarch64-linux-gnu.config b/src/ci/docker/dist-armv7-aarch64-linux/aarch64-linux-gnu.config
new file mode 100644
index 0000000000000..3d30ee49022d8
--- /dev/null
+++ b/src/ci/docker/dist-armv7-aarch64-linux/aarch64-linux-gnu.config
@@ -0,0 +1,551 @@
+#
+# Automatically generated file; DO NOT EDIT.
+# Crosstool-NG Configuration
+#
+CT_CONFIGURE_has_make381=y
+CT_CONFIGURE_has_xz=y
+CT_MODULES=y
+
+#
+# Paths and misc options
+#
+
+#
+# crosstool-NG behavior
+#
+# CT_OBSOLETE is not set
+# CT_EXPERIMENTAL is not set
+# CT_DEBUG_CT is not set
+
+#
+# Paths
+#
+CT_LOCAL_TARBALLS_DIR=""
+CT_WORK_DIR="${CT_TOP_DIR}/.build"
+CT_PREFIX_DIR="/x-tools/${CT_TARGET}"
+CT_INSTALL_DIR="${CT_PREFIX_DIR}"
+CT_RM_RF_PREFIX_DIR=y
+CT_REMOVE_DOCS=y
+CT_INSTALL_DIR_RO=y
+CT_STRIP_HOST_TOOLCHAIN_EXECUTABLES=y
+# CT_STRIP_TARGET_TOOLCHAIN_EXECUTABLES is not set
+
+#
+# Downloading
+#
+# CT_FORBID_DOWNLOAD is not set
+# CT_FORCE_DOWNLOAD is not set
+CT_CONNECT_TIMEOUT=10
+# CT_ONLY_DOWNLOAD is not set
+# CT_USE_MIRROR is not set
+
+#
+# Extracting
+#
+# CT_FORCE_EXTRACT is not set
+CT_OVERIDE_CONFIG_GUESS_SUB=y
+# CT_ONLY_EXTRACT is not set
+CT_PATCH_BUNDLED=y
+# CT_PATCH_LOCAL is not set
+# CT_PATCH_BUNDLED_LOCAL is not set
+# CT_PATCH_LOCAL_BUNDLED is not set
+# CT_PATCH_BUNDLED_FALLBACK_LOCAL is not set
+# CT_PATCH_LOCAL_FALLBACK_BUNDLED is not set
+# CT_PATCH_NONE is not set
+CT_PATCH_ORDER="bundled"
+
+#
+# Build behavior
+#
+CT_PARALLEL_JOBS=0
+CT_LOAD=""
+CT_USE_PIPES=y
+CT_EXTRA_CFLAGS_FOR_BUILD=""
+CT_EXTRA_LDFLAGS_FOR_BUILD=""
+CT_EXTRA_CFLAGS_FOR_HOST=""
+CT_EXTRA_LDFLAGS_FOR_HOST=""
+# CT_CONFIG_SHELL_SH is not set
+# CT_CONFIG_SHELL_ASH is not set
+CT_CONFIG_SHELL_BASH=y
+# CT_CONFIG_SHELL_CUSTOM is not set
+CT_CONFIG_SHELL="${bash}"
+
+#
+# Logging
+#
+# CT_LOG_ERROR is not set
+# CT_LOG_WARN is not set
+CT_LOG_INFO=y
+# CT_LOG_EXTRA is not set
+# CT_LOG_ALL is not set
+# CT_LOG_DEBUG is not set
+CT_LOG_LEVEL_MAX="INFO"
+# CT_LOG_SEE_TOOLS_WARN is not set
+CT_LOG_PROGRESS_BAR=y
+CT_LOG_TO_FILE=y
+CT_LOG_FILE_COMPRESS=y
+
+#
+# Target options
+#
+CT_ARCH="arm"
+CT_ARCH_SUPPORTS_BOTH_MMU=y
+CT_ARCH_SUPPORTS_BOTH_ENDIAN=y
+CT_ARCH_SUPPORTS_32=y
+CT_ARCH_SUPPORTS_64=y
+CT_ARCH_SUPPORTS_WITH_ARCH=y
+CT_ARCH_SUPPORTS_WITH_CPU=y
+CT_ARCH_SUPPORTS_WITH_TUNE=y
+CT_ARCH_DEFAULT_HAS_MMU=y
+CT_ARCH_DEFAULT_LE=y
+CT_ARCH_DEFAULT_32=y
+CT_ARCH_ARCH=""
+CT_ARCH_CPU=""
+CT_ARCH_TUNE=""
+# CT_ARCH_BE is not set
+CT_ARCH_LE=y
+# CT_ARCH_32 is not set
+CT_ARCH_64=y
+CT_ARCH_BITNESS=64
+CT_TARGET_CFLAGS=""
+CT_TARGET_LDFLAGS=""
+# CT_ARCH_alpha is not set
+CT_ARCH_arm=y
+# CT_ARCH_avr is not set
+# CT_ARCH_m68k is not set
+# CT_ARCH_mips is not set
+# CT_ARCH_nios2 is not set
+# CT_ARCH_powerpc is not set
+# CT_ARCH_s390 is not set
+# CT_ARCH_sh is not set
+# CT_ARCH_sparc is not set
+# CT_ARCH_x86 is not set
+# CT_ARCH_xtensa is not set
+CT_ARCH_alpha_AVAILABLE=y
+CT_ARCH_arm_AVAILABLE=y
+CT_ARCH_avr_AVAILABLE=y
+CT_ARCH_m68k_AVAILABLE=y
+CT_ARCH_microblaze_AVAILABLE=y
+CT_ARCH_mips_AVAILABLE=y
+CT_ARCH_nios2_AVAILABLE=y
+CT_ARCH_powerpc_AVAILABLE=y
+CT_ARCH_s390_AVAILABLE=y
+CT_ARCH_sh_AVAILABLE=y
+CT_ARCH_sparc_AVAILABLE=y
+CT_ARCH_x86_AVAILABLE=y
+CT_ARCH_xtensa_AVAILABLE=y
+CT_ARCH_SUFFIX=""
+
+#
+# Generic target options
+#
+# CT_MULTILIB is not set
+CT_ARCH_USE_MMU=y
+CT_ARCH_ENDIAN="little"
+
+#
+# Target optimisations
+#
+CT_ARCH_EXCLUSIVE_WITH_CPU=y
+CT_ARCH_FLOAT=""
+
+#
+# arm other options
+#
+CT_ARCH_ARM_MODE="arm"
+CT_ARCH_ARM_MODE_ARM=y
+# CT_ARCH_ARM_MODE_THUMB is not set
+# CT_ARCH_ARM_INTERWORKING is not set
+CT_ARCH_ARM_EABI_FORCE=y
+CT_ARCH_ARM_EABI=y
+
+#
+# Toolchain options
+#
+
+#
+# General toolchain options
+#
+CT_FORCE_SYSROOT=y
+CT_USE_SYSROOT=y
+CT_SYSROOT_NAME="sysroot"
+CT_SYSROOT_DIR_PREFIX=""
+CT_WANTS_STATIC_LINK=y
+# CT_STATIC_TOOLCHAIN is not set
+CT_TOOLCHAIN_PKGVERSION=""
+CT_TOOLCHAIN_BUGURL=""
+
+#
+# Tuple completion and aliasing
+#
+CT_TARGET_VENDOR="unknown"
+CT_TARGET_ALIAS_SED_EXPR=""
+CT_TARGET_ALIAS=""
+
+#
+# Toolchain type
+#
+CT_CROSS=y
+# CT_CANADIAN is not set
+CT_TOOLCHAIN_TYPE="cross"
+
+#
+# Build system
+#
+CT_BUILD=""
+CT_BUILD_PREFIX=""
+CT_BUILD_SUFFIX=""
+
+#
+# Misc options
+#
+# CT_TOOLCHAIN_ENABLE_NLS is not set
+
+#
+# Operating System
+#
+CT_KERNEL_SUPPORTS_SHARED_LIBS=y
+CT_KERNEL="linux"
+CT_KERNEL_VERSION="4.2.6"
+# CT_KERNEL_bare_metal is not set
+CT_KERNEL_linux=y
+CT_KERNEL_bare_metal_AVAILABLE=y
+CT_KERNEL_linux_AVAILABLE=y
+# CT_KERNEL_V_4_3 is not set
+CT_KERNEL_V_4_2=y
+# CT_KERNEL_V_4_1 is not set
+# CT_KERNEL_V_3_18 is not set
+# CT_KERNEL_V_3_14 is not set
+# CT_KERNEL_V_3_12 is not set
+# CT_KERNEL_V_3_10 is not set
+# CT_KERNEL_V_3_4 is not set
+# CT_KERNEL_V_3_2 is not set
+# CT_KERNEL_V_2_6_32 is not set
+# CT_KERNEL_LINUX_CUSTOM is not set
+CT_KERNEL_windows_AVAILABLE=y
+
+#
+# Common kernel options
+#
+CT_SHARED_LIBS=y
+
+#
+# linux other options
+#
+CT_KERNEL_LINUX_VERBOSITY_0=y
+# CT_KERNEL_LINUX_VERBOSITY_1 is not set
+# CT_KERNEL_LINUX_VERBOSITY_2 is not set
+CT_KERNEL_LINUX_VERBOSE_LEVEL=0
+CT_KERNEL_LINUX_INSTALL_CHECK=y
+
+#
+# Binary utilities
+#
+CT_ARCH_BINFMT_ELF=y
+CT_BINUTILS="binutils"
+CT_BINUTILS_binutils=y
+
+#
+# GNU binutils
+#
+# CT_CC_BINUTILS_SHOW_LINARO is not set
+CT_BINUTILS_V_2_25_1=y
+# CT_BINUTILS_V_2_25 is not set
+# CT_BINUTILS_V_2_24 is not set
+# CT_BINUTILS_V_2_23_2 is not set
+# CT_BINUTILS_V_2_23_1 is not set
+# CT_BINUTILS_V_2_22 is not set
+# CT_BINUTILS_V_2_21_53 is not set
+# CT_BINUTILS_V_2_21_1a is not set
+# CT_BINUTILS_V_2_20_1a is not set
+# CT_BINUTILS_V_2_19_1a is not set
+# CT_BINUTILS_V_2_18a is not set
+CT_BINUTILS_VERSION="2.25.1"
+CT_BINUTILS_2_25_1_or_later=y
+CT_BINUTILS_2_25_or_later=y
+CT_BINUTILS_2_24_or_later=y
+CT_BINUTILS_2_23_or_later=y
+CT_BINUTILS_2_22_or_later=y
+CT_BINUTILS_2_21_or_later=y
+CT_BINUTILS_2_20_or_later=y
+CT_BINUTILS_2_19_or_later=y
+CT_BINUTILS_2_18_or_later=y
+CT_BINUTILS_HAS_HASH_STYLE=y
+CT_BINUTILS_HAS_GOLD=y
+CT_BINUTILS_GOLD_SUPPORTS_ARCH=y
+CT_BINUTILS_GOLD_SUPPORT=y
+CT_BINUTILS_HAS_PLUGINS=y
+CT_BINUTILS_HAS_PKGVERSION_BUGURL=y
+CT_BINUTILS_FORCE_LD_BFD=y
+CT_BINUTILS_LINKER_LD=y
+# CT_BINUTILS_LINKER_LD_GOLD is not set
+# CT_BINUTILS_LINKER_GOLD_LD is not set
+CT_BINUTILS_LINKERS_LIST="ld"
+CT_BINUTILS_LINKER_DEFAULT="bfd"
+# CT_BINUTILS_PLUGINS is not set
+CT_BINUTILS_EXTRA_CONFIG_ARRAY=""
+# CT_BINUTILS_FOR_TARGET is not set
+
+#
+# binutils other options
+#
+
+#
+# C-library
+#
+CT_LIBC="glibc"
+CT_LIBC_VERSION="2.17"
+CT_LIBC_glibc=y
+# CT_LIBC_musl is not set
+# CT_LIBC_uClibc is not set
+CT_LIBC_avr_libc_AVAILABLE=y
+CT_LIBC_glibc_AVAILABLE=y
+CT_THREADS="nptl"
+# CT_CC_GLIBC_SHOW_LINARO is not set
+# CT_LIBC_GLIBC_V_2_22 is not set
+# CT_LIBC_GLIBC_V_2_21 is not set
+# CT_LIBC_GLIBC_V_2_20 is not set
+# CT_LIBC_GLIBC_V_2_19 is not set
+# CT_LIBC_GLIBC_V_2_18 is not set
+CT_LIBC_GLIBC_V_2_17=y
+# CT_LIBC_GLIBC_V_2_16_0 is not set
+# CT_LIBC_GLIBC_V_2_15 is not set
+# CT_LIBC_GLIBC_V_2_14_1 is not set
+# CT_LIBC_GLIBC_V_2_14 is not set
+# CT_LIBC_GLIBC_V_2_13 is not set
+# CT_LIBC_GLIBC_V_2_12_2 is not set
+# CT_LIBC_GLIBC_V_2_12_1 is not set
+# CT_LIBC_GLIBC_V_2_11_1 is not set
+# CT_LIBC_GLIBC_V_2_11 is not set
+# CT_LIBC_GLIBC_V_2_10_1 is not set
+# CT_LIBC_GLIBC_V_2_9 is not set
+# CT_LIBC_GLIBC_V_2_8 is not set
+CT_LIBC_GLIBC_2_17_or_later=y
+CT_LIBC_mingw_AVAILABLE=y
+CT_LIBC_musl_AVAILABLE=y
+CT_LIBC_newlib_AVAILABLE=y
+CT_LIBC_none_AVAILABLE=y
+CT_LIBC_uClibc_AVAILABLE=y
+CT_LIBC_SUPPORT_THREADS_ANY=y
+CT_LIBC_SUPPORT_THREADS_NATIVE=y
+
+#
+# Common C library options
+#
+CT_THREADS_NATIVE=y
+CT_LIBC_XLDD=y
+
+#
+# glibc other options
+#
+# CT_LIBC_GLIBC_PORTS_EXTERNAL is not set
+CT_LIBC_GLIBC_MAY_FORCE_PORTS=y
+CT_LIBC_glibc_familly=y
+CT_LIBC_GLIBC_EXTRA_CONFIG_ARRAY=""
+CT_LIBC_GLIBC_CONFIGPARMS=""
+CT_LIBC_GLIBC_EXTRA_CFLAGS=""
+CT_LIBC_EXTRA_CC_ARGS=""
+# CT_LIBC_DISABLE_VERSIONING is not set
+CT_LIBC_OLDEST_ABI=""
+CT_LIBC_GLIBC_FORCE_UNWIND=y
+CT_LIBC_GLIBC_USE_PORTS=y
+CT_LIBC_ADDONS_LIST=""
+
+#
+# WARNING !!!                                            
+#
+
+#
+#   For glibc >= 2.8, it can happen that the tarballs    
+#
+
+#
+#   for the addons are not available for download.       
+#
+
+#
+#   If that happens, bad luck... Try a previous version  
+#
+
+#
+#   or try again later... :-(                            
+#
+# CT_LIBC_LOCALES is not set
+# CT_LIBC_GLIBC_KERNEL_VERSION_NONE is not set
+CT_LIBC_GLIBC_KERNEL_VERSION_AS_HEADERS=y
+# CT_LIBC_GLIBC_KERNEL_VERSION_CHOSEN is not set
+CT_LIBC_GLIBC_MIN_KERNEL="4.2.6"
+
+#
+# C compiler
+#
+CT_CC="gcc"
+CT_CC_CORE_PASSES_NEEDED=y
+CT_CC_CORE_PASS_1_NEEDED=y
+CT_CC_CORE_PASS_2_NEEDED=y
+CT_CC_gcc=y
+# CT_CC_GCC_SHOW_LINARO is not set
+CT_CC_GCC_V_5_2_0=y
+# CT_CC_GCC_V_4_9_3 is not set
+# CT_CC_GCC_V_4_8_5 is not set
+# CT_CC_GCC_V_4_7_4 is not set
+# CT_CC_GCC_V_4_6_4 is not set
+# CT_CC_GCC_V_4_5_4 is not set
+# CT_CC_GCC_V_4_4_7 is not set
+# CT_CC_GCC_V_4_3_6 is not set
+# CT_CC_GCC_V_4_2_4 is not set
+CT_CC_GCC_4_2_or_later=y
+CT_CC_GCC_4_3_or_later=y
+CT_CC_GCC_4_4_or_later=y
+CT_CC_GCC_4_5_or_later=y
+CT_CC_GCC_4_6_or_later=y
+CT_CC_GCC_4_7_or_later=y
+CT_CC_GCC_4_8_or_later=y
+CT_CC_GCC_4_9_or_later=y
+CT_CC_GCC_5=y
+CT_CC_GCC_5_or_later=y
+CT_CC_GCC_HAS_GRAPHITE=y
+CT_CC_GCC_USE_GRAPHITE=y
+CT_CC_GCC_HAS_LTO=y
+CT_CC_GCC_USE_LTO=y
+CT_CC_GCC_HAS_PKGVERSION_BUGURL=y
+CT_CC_GCC_HAS_BUILD_ID=y
+CT_CC_GCC_HAS_LNK_HASH_STYLE=y
+CT_CC_GCC_USE_GMP_MPFR=y
+CT_CC_GCC_USE_MPC=y
+CT_CC_GCC_HAS_LIBQUADMATH=y
+CT_CC_GCC_HAS_LIBSANITIZER=y
+CT_CC_GCC_VERSION="5.2.0"
+# CT_CC_LANG_FORTRAN is not set
+CT_CC_GCC_ENABLE_CXX_FLAGS=""
+CT_CC_GCC_CORE_EXTRA_CONFIG_ARRAY=""
+CT_CC_GCC_EXTRA_CONFIG_ARRAY=""
+CT_CC_GCC_EXTRA_ENV_ARRAY=""
+CT_CC_GCC_STATIC_LIBSTDCXX=y
+# CT_CC_GCC_SYSTEM_ZLIB is not set
+
+#
+# Optimisation features
+#
+
+#
+# Settings for libraries running on target
+#
+CT_CC_GCC_ENABLE_TARGET_OPTSPACE=y
+# CT_CC_GCC_LIBMUDFLAP is not set
+# CT_CC_GCC_LIBGOMP is not set
+# CT_CC_GCC_LIBSSP is not set
+# CT_CC_GCC_LIBQUADMATH is not set
+# CT_CC_GCC_LIBSANITIZER is not set
+
+#
+# Misc. obscure options.
+#
+CT_CC_CXA_ATEXIT=y
+# CT_CC_GCC_DISABLE_PCH is not set
+CT_CC_GCC_SJLJ_EXCEPTIONS=m
+CT_CC_GCC_LDBL_128=m
+# CT_CC_GCC_BUILD_ID is not set
+CT_CC_GCC_LNK_HASH_STYLE_DEFAULT=y
+# CT_CC_GCC_LNK_HASH_STYLE_SYSV is not set
+# CT_CC_GCC_LNK_HASH_STYLE_GNU is not set
+# CT_CC_GCC_LNK_HASH_STYLE_BOTH is not set
+CT_CC_GCC_LNK_HASH_STYLE=""
+CT_CC_GCC_DEC_FLOAT_AUTO=y
+# CT_CC_GCC_DEC_FLOAT_BID is not set
+# CT_CC_GCC_DEC_FLOAT_DPD is not set
+# CT_CC_GCC_DEC_FLOATS_NO is not set
+CT_CC_SUPPORT_CXX=y
+CT_CC_SUPPORT_FORTRAN=y
+CT_CC_SUPPORT_JAVA=y
+CT_CC_SUPPORT_ADA=y
+CT_CC_SUPPORT_OBJC=y
+CT_CC_SUPPORT_OBJCXX=y
+CT_CC_SUPPORT_GOLANG=y
+
+#
+# Additional supported languages:
+#
+CT_CC_LANG_CXX=y
+# CT_CC_LANG_JAVA is not set
+
+#
+# Debug facilities
+#
+# CT_DEBUG_dmalloc is not set
+# CT_DEBUG_duma is not set
+# CT_DEBUG_gdb is not set
+# CT_DEBUG_ltrace is not set
+# CT_DEBUG_strace is not set
+
+#
+# Companion libraries
+#
+CT_COMPLIBS_NEEDED=y
+CT_LIBICONV_NEEDED=y
+CT_GETTEXT_NEEDED=y
+CT_GMP_NEEDED=y
+CT_MPFR_NEEDED=y
+CT_ISL_NEEDED=y
+CT_MPC_NEEDED=y
+CT_COMPLIBS=y
+CT_LIBICONV=y
+CT_GETTEXT=y
+CT_GMP=y
+CT_MPFR=y
+CT_ISL=y
+CT_MPC=y
+CT_LIBICONV_V_1_14=y
+CT_LIBICONV_VERSION="1.14"
+CT_GETTEXT_V_0_19_6=y
+CT_GETTEXT_VERSION="0.19.6"
+CT_GMP_V_6_0_0=y
+# CT_GMP_V_5_1_3 is not set
+# CT_GMP_V_5_1_1 is not set
+# CT_GMP_V_5_0_2 is not set
+# CT_GMP_V_5_0_1 is not set
+# CT_GMP_V_4_3_2 is not set
+# CT_GMP_V_4_3_1 is not set
+# CT_GMP_V_4_3_0 is not set
+CT_GMP_5_0_2_or_later=y
+CT_GMP_VERSION="6.0.0a"
+CT_MPFR_V_3_1_3=y
+# CT_MPFR_V_3_1_2 is not set
+# CT_MPFR_V_3_1_0 is not set
+# CT_MPFR_V_3_0_1 is not set
+# CT_MPFR_V_3_0_0 is not set
+# CT_MPFR_V_2_4_2 is not set
+# CT_MPFR_V_2_4_1 is not set
+# CT_MPFR_V_2_4_0 is not set
+CT_MPFR_VERSION="3.1.3"
+CT_ISL_V_0_14=y
+# CT_ISL_V_0_12_2 is not set
+CT_ISL_V_0_14_or_later=y
+CT_ISL_V_0_12_or_later=y
+CT_ISL_VERSION="0.14"
+# CT_CLOOG_V_0_18_4 is not set
+# CT_CLOOG_V_0_18_1 is not set
+# CT_CLOOG_V_0_18_0 is not set
+CT_MPC_V_1_0_3=y
+# CT_MPC_V_1_0_2 is not set
+# CT_MPC_V_1_0_1 is not set
+# CT_MPC_V_1_0 is not set
+# CT_MPC_V_0_9 is not set
+# CT_MPC_V_0_8_2 is not set
+# CT_MPC_V_0_8_1 is not set
+# CT_MPC_V_0_7 is not set
+CT_MPC_VERSION="1.0.3"
+
+#
+# Companion libraries common options
+#
+# CT_COMPLIBS_CHECK is not set
+
+#
+# Companion tools
+#
+
+#
+# READ HELP before you say 'Y' below !!!
+#
+# CT_COMP_TOOLS is not set
diff --git a/src/ci/docker/dist-armv7-aarch64-linux/armv7-linux-gnueabihf.config b/src/ci/docker/dist-armv7-aarch64-linux/armv7-linux-gnueabihf.config
new file mode 100644
index 0000000000000..79d6c77c41152
--- /dev/null
+++ b/src/ci/docker/dist-armv7-aarch64-linux/armv7-linux-gnueabihf.config
@@ -0,0 +1,569 @@
+#
+# Automatically generated file; DO NOT EDIT.
+# Crosstool-NG Configuration
+#
+CT_CONFIGURE_has_make381=y
+CT_MODULES=y
+
+#
+# Paths and misc options
+#
+
+#
+# crosstool-NG behavior
+#
+# CT_OBSOLETE is not set
+# CT_EXPERIMENTAL is not set
+# CT_DEBUG_CT is not set
+
+#
+# Paths
+#
+CT_LOCAL_TARBALLS_DIR=""
+CT_WORK_DIR="${CT_TOP_DIR}/.build"
+CT_PREFIX_DIR="/x-tools/${CT_TARGET}"
+CT_INSTALL_DIR="${CT_PREFIX_DIR}"
+CT_RM_RF_PREFIX_DIR=y
+CT_REMOVE_DOCS=y
+CT_INSTALL_DIR_RO=y
+CT_STRIP_HOST_TOOLCHAIN_EXECUTABLES=y
+# CT_STRIP_TARGET_TOOLCHAIN_EXECUTABLES is not set
+
+#
+# Downloading
+#
+# CT_FORBID_DOWNLOAD is not set
+# CT_FORCE_DOWNLOAD is not set
+CT_CONNECT_TIMEOUT=10
+# CT_ONLY_DOWNLOAD is not set
+# CT_USE_MIRROR is not set
+
+#
+# Extracting
+#
+# CT_FORCE_EXTRACT is not set
+CT_OVERIDE_CONFIG_GUESS_SUB=y
+# CT_ONLY_EXTRACT is not set
+CT_PATCH_BUNDLED=y
+# CT_PATCH_LOCAL is not set
+# CT_PATCH_BUNDLED_LOCAL is not set
+# CT_PATCH_LOCAL_BUNDLED is not set
+# CT_PATCH_BUNDLED_FALLBACK_LOCAL is not set
+# CT_PATCH_LOCAL_FALLBACK_BUNDLED is not set
+# CT_PATCH_NONE is not set
+CT_PATCH_ORDER="bundled"
+
+#
+# Build behavior
+#
+CT_PARALLEL_JOBS=0
+CT_LOAD=""
+CT_USE_PIPES=y
+CT_EXTRA_CFLAGS_FOR_BUILD=""
+CT_EXTRA_LDFLAGS_FOR_BUILD=""
+CT_EXTRA_CFLAGS_FOR_HOST=""
+CT_EXTRA_LDFLAGS_FOR_HOST=""
+# CT_CONFIG_SHELL_SH is not set
+# CT_CONFIG_SHELL_ASH is not set
+CT_CONFIG_SHELL_BASH=y
+# CT_CONFIG_SHELL_CUSTOM is not set
+CT_CONFIG_SHELL="${bash}"
+
+#
+# Logging
+#
+# CT_LOG_ERROR is not set
+# CT_LOG_WARN is not set
+CT_LOG_INFO=y
+# CT_LOG_EXTRA is not set
+# CT_LOG_ALL is not set
+# CT_LOG_DEBUG is not set
+CT_LOG_LEVEL_MAX="INFO"
+# CT_LOG_SEE_TOOLS_WARN is not set
+CT_LOG_PROGRESS_BAR=y
+CT_LOG_TO_FILE=y
+CT_LOG_FILE_COMPRESS=y
+
+#
+# Target options
+#
+CT_ARCH="arm"
+CT_ARCH_SUPPORTS_BOTH_MMU=y
+CT_ARCH_SUPPORTS_BOTH_ENDIAN=y
+CT_ARCH_SUPPORTS_32=y
+CT_ARCH_SUPPORTS_64=y
+CT_ARCH_SUPPORTS_WITH_ARCH=y
+CT_ARCH_SUPPORTS_WITH_CPU=y
+CT_ARCH_SUPPORTS_WITH_TUNE=y
+CT_ARCH_SUPPORTS_WITH_FLOAT=y
+CT_ARCH_SUPPORTS_WITH_FPU=y
+CT_ARCH_SUPPORTS_SOFTFP=y
+CT_ARCH_DEFAULT_HAS_MMU=y
+CT_ARCH_DEFAULT_LE=y
+CT_ARCH_DEFAULT_32=y
+CT_ARCH_ARCH="armv7-a"
+CT_ARCH_CPU=""
+CT_ARCH_TUNE=""
+CT_ARCH_FPU="vfpv3-d16"
+# CT_ARCH_BE is not set
+CT_ARCH_LE=y
+CT_ARCH_32=y
+# CT_ARCH_64 is not set
+CT_ARCH_BITNESS=32
+CT_ARCH_FLOAT_HW=y
+# CT_ARCH_FLOAT_SW is not set
+CT_TARGET_CFLAGS=""
+CT_TARGET_LDFLAGS=""
+# CT_ARCH_alpha is not set
+CT_ARCH_arm=y
+# CT_ARCH_avr is not set
+# CT_ARCH_m68k is not set
+# CT_ARCH_mips is not set
+# CT_ARCH_nios2 is not set
+# CT_ARCH_powerpc is not set
+# CT_ARCH_s390 is not set
+# CT_ARCH_sh is not set
+# CT_ARCH_sparc is not set
+# CT_ARCH_x86 is not set
+# CT_ARCH_xtensa is not set
+CT_ARCH_alpha_AVAILABLE=y
+CT_ARCH_arm_AVAILABLE=y
+CT_ARCH_avr_AVAILABLE=y
+CT_ARCH_m68k_AVAILABLE=y
+CT_ARCH_microblaze_AVAILABLE=y
+CT_ARCH_mips_AVAILABLE=y
+CT_ARCH_nios2_AVAILABLE=y
+CT_ARCH_powerpc_AVAILABLE=y
+CT_ARCH_s390_AVAILABLE=y
+CT_ARCH_sh_AVAILABLE=y
+CT_ARCH_sparc_AVAILABLE=y
+CT_ARCH_x86_AVAILABLE=y
+CT_ARCH_xtensa_AVAILABLE=y
+CT_ARCH_SUFFIX="v7"
+
+#
+# Generic target options
+#
+# CT_MULTILIB is not set
+CT_ARCH_USE_MMU=y
+CT_ARCH_ENDIAN="little"
+
+#
+# Target optimisations
+#
+CT_ARCH_EXCLUSIVE_WITH_CPU=y
+# CT_ARCH_FLOAT_AUTO is not set
+# CT_ARCH_FLOAT_SOFTFP is not set
+CT_ARCH_FLOAT="hard"
+# CT_ARCH_ALPHA_EV4 is not set
+# CT_ARCH_ALPHA_EV45 is not set
+# CT_ARCH_ALPHA_EV5 is not set
+# CT_ARCH_ALPHA_EV56 is not set
+# CT_ARCH_ALPHA_EV6 is not set
+# CT_ARCH_ALPHA_EV67 is not set
+
+#
+# arm other options
+#
+CT_ARCH_ARM_MODE="thumb"
+# CT_ARCH_ARM_MODE_ARM is not set
+CT_ARCH_ARM_MODE_THUMB=y
+# CT_ARCH_ARM_INTERWORKING is not set
+CT_ARCH_ARM_EABI_FORCE=y
+CT_ARCH_ARM_EABI=y
+CT_ARCH_ARM_TUPLE_USE_EABIHF=y
+
+#
+# Toolchain options
+#
+
+#
+# General toolchain options
+#
+CT_FORCE_SYSROOT=y
+CT_USE_SYSROOT=y
+CT_SYSROOT_NAME="sysroot"
+CT_SYSROOT_DIR_PREFIX=""
+CT_WANTS_STATIC_LINK=y
+# CT_STATIC_TOOLCHAIN is not set
+CT_TOOLCHAIN_PKGVERSION=""
+CT_TOOLCHAIN_BUGURL=""
+
+#
+# Tuple completion and aliasing
+#
+CT_TARGET_VENDOR="unknown"
+CT_TARGET_ALIAS_SED_EXPR=""
+CT_TARGET_ALIAS=""
+
+#
+# Toolchain type
+#
+CT_CROSS=y
+# CT_CANADIAN is not set
+CT_TOOLCHAIN_TYPE="cross"
+
+#
+# Build system
+#
+CT_BUILD=""
+CT_BUILD_PREFIX=""
+CT_BUILD_SUFFIX=""
+
+#
+# Misc options
+#
+# CT_TOOLCHAIN_ENABLE_NLS is not set
+
+#
+# Operating System
+#
+CT_KERNEL_SUPPORTS_SHARED_LIBS=y
+CT_KERNEL="linux"
+CT_KERNEL_VERSION="3.2.72"
+# CT_KERNEL_bare_metal is not set
+CT_KERNEL_linux=y
+CT_KERNEL_bare_metal_AVAILABLE=y
+CT_KERNEL_linux_AVAILABLE=y
+# CT_KERNEL_V_4_3 is not set
+# CT_KERNEL_V_4_2 is not set
+# CT_KERNEL_V_4_1 is not set
+# CT_KERNEL_V_3_18 is not set
+# CT_KERNEL_V_3_14 is not set
+# CT_KERNEL_V_3_12 is not set
+# CT_KERNEL_V_3_10 is not set
+# CT_KERNEL_V_3_4 is not set
+CT_KERNEL_V_3_2=y
+# CT_KERNEL_V_2_6_32 is not set
+# CT_KERNEL_LINUX_CUSTOM is not set
+CT_KERNEL_windows_AVAILABLE=y
+
+#
+# Common kernel options
+#
+CT_SHARED_LIBS=y
+
+#
+# linux other options
+#
+CT_KERNEL_LINUX_VERBOSITY_0=y
+# CT_KERNEL_LINUX_VERBOSITY_1 is not set
+# CT_KERNEL_LINUX_VERBOSITY_2 is not set
+CT_KERNEL_LINUX_VERBOSE_LEVEL=0
+CT_KERNEL_LINUX_INSTALL_CHECK=y
+
+#
+# Binary utilities
+#
+CT_ARCH_BINFMT_ELF=y
+CT_BINUTILS="binutils"
+CT_BINUTILS_binutils=y
+
+#
+# GNU binutils
+#
+# CT_CC_BINUTILS_SHOW_LINARO is not set
+CT_BINUTILS_V_2_25_1=y
+# CT_BINUTILS_V_2_25 is not set
+# CT_BINUTILS_V_2_24 is not set
+# CT_BINUTILS_V_2_23_2 is not set
+# CT_BINUTILS_V_2_23_1 is not set
+# CT_BINUTILS_V_2_22 is not set
+# CT_BINUTILS_V_2_21_53 is not set
+# CT_BINUTILS_V_2_21_1a is not set
+# CT_BINUTILS_V_2_20_1a is not set
+# CT_BINUTILS_V_2_19_1a is not set
+# CT_BINUTILS_V_2_18a is not set
+CT_BINUTILS_VERSION="2.25.1"
+CT_BINUTILS_2_25_1_or_later=y
+CT_BINUTILS_2_25_or_later=y
+CT_BINUTILS_2_24_or_later=y
+CT_BINUTILS_2_23_or_later=y
+CT_BINUTILS_2_22_or_later=y
+CT_BINUTILS_2_21_or_later=y
+CT_BINUTILS_2_20_or_later=y
+CT_BINUTILS_2_19_or_later=y
+CT_BINUTILS_2_18_or_later=y
+CT_BINUTILS_HAS_HASH_STYLE=y
+CT_BINUTILS_HAS_GOLD=y
+CT_BINUTILS_GOLD_SUPPORTS_ARCH=y
+CT_BINUTILS_GOLD_SUPPORT=y
+CT_BINUTILS_HAS_PLUGINS=y
+CT_BINUTILS_HAS_PKGVERSION_BUGURL=y
+CT_BINUTILS_FORCE_LD_BFD=y
+CT_BINUTILS_LINKER_LD=y
+# CT_BINUTILS_LINKER_LD_GOLD is not set
+# CT_BINUTILS_LINKER_GOLD_LD is not set
+CT_BINUTILS_LINKERS_LIST="ld"
+CT_BINUTILS_LINKER_DEFAULT="bfd"
+# CT_BINUTILS_PLUGINS is not set
+CT_BINUTILS_EXTRA_CONFIG_ARRAY=""
+# CT_BINUTILS_FOR_TARGET is not set
+
+#
+# binutils other options
+#
+
+#
+# C-library
+#
+CT_LIBC="glibc"
+CT_LIBC_VERSION="2.16.0"
+CT_LIBC_glibc=y
+# CT_LIBC_musl is not set
+# CT_LIBC_newlib is not set
+# CT_LIBC_none is not set
+# CT_LIBC_uClibc is not set
+CT_LIBC_avr_libc_AVAILABLE=y
+CT_LIBC_glibc_AVAILABLE=y
+CT_THREADS="nptl"
+# CT_CC_GLIBC_SHOW_LINARO is not set
+# CT_LIBC_GLIBC_V_2_22 is not set
+# CT_LIBC_GLIBC_V_2_21 is not set
+# CT_LIBC_GLIBC_V_2_20 is not set
+# CT_LIBC_GLIBC_V_2_19 is not set
+# CT_LIBC_GLIBC_V_2_18 is not set
+# CT_LIBC_GLIBC_V_2_17 is not set
+CT_LIBC_GLIBC_V_2_16_0=y
+# CT_LIBC_GLIBC_V_2_15 is not set
+# CT_LIBC_GLIBC_V_2_14_1 is not set
+# CT_LIBC_GLIBC_V_2_14 is not set
+# CT_LIBC_GLIBC_V_2_13 is not set
+# CT_LIBC_GLIBC_V_2_12_2 is not set
+# CT_LIBC_GLIBC_V_2_12_1 is not set
+# CT_LIBC_GLIBC_V_2_11_1 is not set
+# CT_LIBC_GLIBC_V_2_11 is not set
+# CT_LIBC_GLIBC_V_2_10_1 is not set
+# CT_LIBC_GLIBC_V_2_9 is not set
+# CT_LIBC_GLIBC_V_2_8 is not set
+CT_LIBC_mingw_AVAILABLE=y
+CT_LIBC_musl_AVAILABLE=y
+CT_LIBC_newlib_AVAILABLE=y
+CT_LIBC_none_AVAILABLE=y
+CT_LIBC_uClibc_AVAILABLE=y
+CT_LIBC_SUPPORT_THREADS_ANY=y
+CT_LIBC_SUPPORT_THREADS_NATIVE=y
+
+#
+# Common C library options
+#
+CT_THREADS_NATIVE=y
+CT_LIBC_XLDD=y
+
+#
+# glibc other options
+#
+CT_LIBC_GLIBC_PORTS_EXTERNAL=y
+CT_LIBC_GLIBC_MAY_FORCE_PORTS=y
+CT_LIBC_glibc_familly=y
+CT_LIBC_GLIBC_EXTRA_CONFIG_ARRAY=""
+CT_LIBC_GLIBC_CONFIGPARMS=""
+CT_LIBC_GLIBC_EXTRA_CFLAGS=""
+CT_LIBC_EXTRA_CC_ARGS=""
+# CT_LIBC_DISABLE_VERSIONING is not set
+CT_LIBC_OLDEST_ABI=""
+CT_LIBC_GLIBC_FORCE_UNWIND=y
+CT_LIBC_GLIBC_USE_PORTS=y
+CT_LIBC_ADDONS_LIST=""
+
+#
+# WARNING !!!                                            
+#
+
+#
+#   For glibc >= 2.8, it can happen that the tarballs    
+#
+
+#
+#   for the addons are not available for download.       
+#
+
+#
+#   If that happens, bad luck... Try a previous version  
+#
+
+#
+#   or try again later... :-(                            
+#
+# CT_LIBC_LOCALES is not set
+# CT_LIBC_GLIBC_KERNEL_VERSION_NONE is not set
+CT_LIBC_GLIBC_KERNEL_VERSION_AS_HEADERS=y
+# CT_LIBC_GLIBC_KERNEL_VERSION_CHOSEN is not set
+CT_LIBC_GLIBC_MIN_KERNEL="3.2.72"
+
+#
+# C compiler
+#
+CT_CC="gcc"
+CT_CC_CORE_PASSES_NEEDED=y
+CT_CC_CORE_PASS_1_NEEDED=y
+CT_CC_CORE_PASS_2_NEEDED=y
+CT_CC_gcc=y
+# CT_CC_GCC_SHOW_LINARO is not set
+# CT_CC_GCC_V_5_2_0 is not set
+CT_CC_GCC_V_4_9_3=y
+# CT_CC_GCC_V_4_8_5 is not set
+# CT_CC_GCC_V_4_7_4 is not set
+# CT_CC_GCC_V_4_6_4 is not set
+# CT_CC_GCC_V_4_5_4 is not set
+# CT_CC_GCC_V_4_4_7 is not set
+# CT_CC_GCC_V_4_3_6 is not set
+# CT_CC_GCC_V_4_2_4 is not set
+CT_CC_GCC_4_2_or_later=y
+CT_CC_GCC_4_3_or_later=y
+CT_CC_GCC_4_4_or_later=y
+CT_CC_GCC_4_5_or_later=y
+CT_CC_GCC_4_6_or_later=y
+CT_CC_GCC_4_7_or_later=y
+CT_CC_GCC_4_8_or_later=y
+CT_CC_GCC_4_9=y
+CT_CC_GCC_4_9_or_later=y
+CT_CC_GCC_HAS_GRAPHITE=y
+CT_CC_GCC_USE_GRAPHITE=y
+CT_CC_GCC_HAS_LTO=y
+CT_CC_GCC_USE_LTO=y
+CT_CC_GCC_HAS_PKGVERSION_BUGURL=y
+CT_CC_GCC_HAS_BUILD_ID=y
+CT_CC_GCC_HAS_LNK_HASH_STYLE=y
+CT_CC_GCC_USE_GMP_MPFR=y
+CT_CC_GCC_USE_MPC=y
+CT_CC_GCC_HAS_LIBQUADMATH=y
+CT_CC_GCC_HAS_LIBSANITIZER=y
+CT_CC_GCC_VERSION="4.9.3"
+# CT_CC_LANG_FORTRAN is not set
+CT_CC_GCC_ENABLE_CXX_FLAGS=""
+CT_CC_GCC_CORE_EXTRA_CONFIG_ARRAY=""
+CT_CC_GCC_EXTRA_CONFIG_ARRAY=""
+CT_CC_GCC_EXTRA_ENV_ARRAY=""
+CT_CC_GCC_STATIC_LIBSTDCXX=y
+# CT_CC_GCC_SYSTEM_ZLIB is not set
+
+#
+# Optimisation features
+#
+
+#
+# Settings for libraries running on target
+#
+CT_CC_GCC_ENABLE_TARGET_OPTSPACE=y
+# CT_CC_GCC_LIBMUDFLAP is not set
+# CT_CC_GCC_LIBGOMP is not set
+# CT_CC_GCC_LIBSSP is not set
+# CT_CC_GCC_LIBQUADMATH is not set
+# CT_CC_GCC_LIBSANITIZER is not set
+
+#
+# Misc. obscure options.
+#
+CT_CC_CXA_ATEXIT=y
+# CT_CC_GCC_DISABLE_PCH is not set
+CT_CC_GCC_SJLJ_EXCEPTIONS=m
+CT_CC_GCC_LDBL_128=m
+# CT_CC_GCC_BUILD_ID is not set
+CT_CC_GCC_LNK_HASH_STYLE_DEFAULT=y
+# CT_CC_GCC_LNK_HASH_STYLE_SYSV is not set
+# CT_CC_GCC_LNK_HASH_STYLE_GNU is not set
+# CT_CC_GCC_LNK_HASH_STYLE_BOTH is not set
+CT_CC_GCC_LNK_HASH_STYLE=""
+CT_CC_GCC_DEC_FLOAT_AUTO=y
+# CT_CC_GCC_DEC_FLOAT_BID is not set
+# CT_CC_GCC_DEC_FLOAT_DPD is not set
+# CT_CC_GCC_DEC_FLOATS_NO is not set
+CT_CC_SUPPORT_CXX=y
+CT_CC_SUPPORT_FORTRAN=y
+CT_CC_SUPPORT_JAVA=y
+CT_CC_SUPPORT_ADA=y
+CT_CC_SUPPORT_OBJC=y
+CT_CC_SUPPORT_OBJCXX=y
+CT_CC_SUPPORT_GOLANG=y
+
+#
+# Additional supported languages:
+#
+CT_CC_LANG_CXX=y
+# CT_CC_LANG_JAVA is not set
+
+#
+# Debug facilities
+#
+# CT_DEBUG_dmalloc is not set
+# CT_DEBUG_duma is not set
+# CT_DEBUG_gdb is not set
+# CT_DEBUG_ltrace is not set
+# CT_DEBUG_strace is not set
+
+#
+# Companion libraries
+#
+CT_COMPLIBS_NEEDED=y
+CT_LIBICONV_NEEDED=y
+CT_GETTEXT_NEEDED=y
+CT_GMP_NEEDED=y
+CT_MPFR_NEEDED=y
+CT_ISL_NEEDED=y
+CT_CLOOG_NEEDED=y
+CT_MPC_NEEDED=y
+CT_COMPLIBS=y
+CT_LIBICONV=y
+CT_GETTEXT=y
+CT_GMP=y
+CT_MPFR=y
+CT_ISL=y
+CT_CLOOG=y
+CT_MPC=y
+CT_LIBICONV_V_1_14=y
+CT_LIBICONV_VERSION="1.14"
+CT_GETTEXT_V_0_19_6=y
+CT_GETTEXT_VERSION="0.19.6"
+CT_GMP_V_6_0_0=y
+# CT_GMP_V_5_1_3 is not set
+# CT_GMP_V_5_1_1 is not set
+# CT_GMP_V_5_0_2 is not set
+# CT_GMP_V_5_0_1 is not set
+# CT_GMP_V_4_3_2 is not set
+# CT_GMP_V_4_3_1 is not set
+# CT_GMP_V_4_3_0 is not set
+CT_GMP_5_0_2_or_later=y
+CT_GMP_VERSION="6.0.0a"
+CT_MPFR_V_3_1_3=y
+# CT_MPFR_V_3_1_2 is not set
+# CT_MPFR_V_3_1_0 is not set
+# CT_MPFR_V_3_0_1 is not set
+# CT_MPFR_V_3_0_0 is not set
+# CT_MPFR_V_2_4_2 is not set
+# CT_MPFR_V_2_4_1 is not set
+# CT_MPFR_V_2_4_0 is not set
+CT_MPFR_VERSION="3.1.3"
+CT_ISL_V_0_14=y
+CT_ISL_V_0_14_or_later=y
+CT_ISL_V_0_12_or_later=y
+CT_ISL_VERSION="0.14"
+CT_CLOOG_V_0_18_4=y
+# CT_CLOOG_V_0_18_1 is not set
+# CT_CLOOG_V_0_18_0 is not set
+CT_CLOOG_VERSION="0.18.4"
+CT_CLOOG_0_18_4_or_later=y
+CT_CLOOG_0_18_or_later=y
+CT_MPC_V_1_0_3=y
+# CT_MPC_V_1_0_2 is not set
+# CT_MPC_V_1_0_1 is not set
+# CT_MPC_V_1_0 is not set
+# CT_MPC_V_0_9 is not set
+# CT_MPC_V_0_8_2 is not set
+# CT_MPC_V_0_8_1 is not set
+# CT_MPC_V_0_7 is not set
+CT_MPC_VERSION="1.0.3"
+
+#
+# Companion libraries common options
+#
+# CT_COMPLIBS_CHECK is not set
+
+#
+# Companion tools
+#
+
+#
+# READ HELP before you say 'Y' below !!!
+#
+# CT_COMP_TOOLS is not set
diff --git a/src/ci/docker/dist-armv7-aarch64-linux/build-toolchains.sh b/src/ci/docker/dist-armv7-aarch64-linux/build-toolchains.sh
new file mode 100755
index 0000000000000..ebd5ef4cfc492
--- /dev/null
+++ b/src/ci/docker/dist-armv7-aarch64-linux/build-toolchains.sh
@@ -0,0 +1,45 @@
+#!/bin/bash
+# Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+# file at the top-level directory of this distribution and at
+# http://rust-lang.org/COPYRIGHT.
+#
+# Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+# http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+# <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+# option. This file may not be copied, modified, or distributed
+# except according to those terms.
+
+set -ex
+
+hide_output() {
+  set +x
+  on_err="
+echo ERROR: An error was encountered with the build.
+cat /tmp/build.log
+exit 1
+"
+  trap "$on_err" ERR
+  bash -c "while true; do sleep 30; echo \$(date) - building ...; done" &
+  PING_LOOP_PID=$!
+  $@ &> /tmp/build.log
+  rm /tmp/build.log
+  trap - ERR
+  kill $PING_LOOP_PID
+  set -x
+}
+
+mkdir build
+cd build
+cp ../armv7-linux-gnueabihf.config .config
+ct-ng oldconfig
+hide_output ct-ng build
+cd ..
+rm -rf build
+
+mkdir build
+cd build
+cp ../aarch64-linux-gnu.config .config
+ct-ng oldconfig
+hide_output ct-ng build
+cd ..
+rm -rf build
diff --git a/src/ci/docker/dist-freebsd/Dockerfile b/src/ci/docker/dist-freebsd/Dockerfile
index b49396c935c00..4b6db62d38971 100644
--- a/src/ci/docker/dist-freebsd/Dockerfile
+++ b/src/ci/docker/dist-freebsd/Dockerfile
@@ -35,11 +35,8 @@ ENV \
     CC_i686_unknown_freebsd=i686-unknown-freebsd10-gcc \
     CXX_i686_unknown_freebsd=i686-unknown-freebsd10-g++
 
-ENV RUST_CONFIGURE_ARGS \
-        --host=x86_64-unknown-freebsd,i686-unknown-freebsd
-ENV SCRIPT \
-      python2.7 ../x.py dist \
-        --host x86_64-unknown-freebsd \
-        --target x86_64-unknown-freebsd \
-        --host i686-unknown-freebsd \
-        --target i686-unknown-freebsd
+ENV HOSTS=x86_64-unknown-freebsd
+ENV HOSTS=$HOSTS,i686-unknown-freebsd
+
+ENV RUST_CONFIGURE_ARGS --host=$HOSTS
+ENV SCRIPT python2.7 ../x.py dist --host $HOSTS --target $HOSTS
diff --git a/src/ci/docker/dist-mips-linux/Dockerfile b/src/ci/docker/dist-mips-linux/Dockerfile
index a495cf57dc51c..df189c2580977 100644
--- a/src/ci/docker/dist-mips-linux/Dockerfile
+++ b/src/ci/docker/dist-mips-linux/Dockerfile
@@ -24,11 +24,8 @@ RUN curl -OL https://github.com/Yelp/dumb-init/releases/download/v1.2.0/dumb-ini
     rm dumb-init_*.deb
 ENTRYPOINT ["/usr/bin/dumb-init", "--"]
 
-ENV RUST_CONFIGURE_ARGS \
-      --host=mips-unknown-linux-gnu,mipsel-unknown-linux-gnu
-ENV SCRIPT \
-      python2.7 ../x.py dist \
-        --host mips-unknown-linux-gnu \
-        --target mips-unknown-linux-gnu \
-        --host mipsel-unknown-linux-gnu \
-        --target mipsel-unknown-linux-gnu
+ENV HOSTS=mips-unknown-linux-gnu
+ENV HOSTS=$HOSTS,mipsel-unknown-linux-gnu
+
+ENV RUST_CONFIGURE_ARGS --host=$HOSTS
+ENV SCRIPT python2.7 ../x.py dist --host $HOSTS --target $HOSTS
diff --git a/src/ci/docker/dist-mips64-linux/Dockerfile b/src/ci/docker/dist-mips64-linux/Dockerfile
index bdb634f530392..9152965caee54 100644
--- a/src/ci/docker/dist-mips64-linux/Dockerfile
+++ b/src/ci/docker/dist-mips64-linux/Dockerfile
@@ -24,11 +24,8 @@ RUN curl -OL https://github.com/Yelp/dumb-init/releases/download/v1.2.0/dumb-ini
     rm dumb-init_*.deb
 ENTRYPOINT ["/usr/bin/dumb-init", "--"]
 
-ENV RUST_CONFIGURE_ARGS \
-      --host=mips64-unknown-linux-gnuabi64,mips64el-unknown-linux-gnuabi64
-ENV SCRIPT \
-      python2.7 ../x.py dist \
-        --host mips64-unknown-linux-gnuabi64 \
-        --target mips64-unknown-linux-gnuabi64 \
-        --host mips64el-unknown-linux-gnuabi64 \
-        --target mips64el-unknown-linux-gnuabi64
+ENV HOSTS=mips64-unknown-linux-gnuabi64
+ENV HOSTS=$HOSTS,mips64el-unknown-linux-gnuabi64
+
+ENV RUST_CONFIGURE_ARGS --host=$HOSTS
+ENV SCRIPT python2.7 ../x.py dist --host $HOSTS --target $HOSTS
diff --git a/src/ci/docker/dist-powerpc-linux/Dockerfile b/src/ci/docker/dist-powerpc-linux/Dockerfile
index 579824dfdb41a..d5f9e5269f13d 100644
--- a/src/ci/docker/dist-powerpc-linux/Dockerfile
+++ b/src/ci/docker/dist-powerpc-linux/Dockerfile
@@ -23,12 +23,10 @@ RUN curl -OL https://github.com/Yelp/dumb-init/releases/download/v1.2.0/dumb-ini
     rm dumb-init_*.deb
 ENTRYPOINT ["/usr/bin/dumb-init", "--"]
 
-ENV RUST_CONFIGURE_ARGS \
-      --host=powerpc-unknown-linux-gnu
-ENV SCRIPT \
-      python2.7 ../x.py dist \
-        --host powerpc-unknown-linux-gnu \
-        --target powerpc-unknown-linux-gnu
+ENV HOSTS=powerpc-unknown-linux-gnu
+
+ENV RUST_CONFIGURE_ARGS --host=$HOSTS
+ENV SCRIPT python2.7 ../x.py dist --host $HOSTS --target $HOSTS
 
 # FIXME(#36150) this will fail the bootstrap. Probably means something bad is
 #               happening!
diff --git a/src/ci/docker/dist-powerpc64-linux/Dockerfile b/src/ci/docker/dist-powerpc64-linux/Dockerfile
index 33877d4b3e9f1..3b222581bd407 100644
--- a/src/ci/docker/dist-powerpc64-linux/Dockerfile
+++ b/src/ci/docker/dist-powerpc64-linux/Dockerfile
@@ -29,11 +29,8 @@ ENV \
     CC_powerpc64_unknown_linux_gnu=powerpc64-linux-gnu-gcc \
     CXX_powerpc64_unknown_linux_gnu=powerpc64-linux-gnu-g++
 
-ENV RUST_CONFIGURE_ARGS \
-      --host=powerpc64-unknown-linux-gnu,powerpc64le-unknown-linux-gnu
-ENV SCRIPT \
-      python2.7 ../x.py dist \
-        --host powerpc64-unknown-linux-gnu \
-        --target powerpc64-unknown-linux-gnu \
-        --host powerpc64le-unknown-linux-gnu \
-        --target powerpc64le-unknown-linux-gnu
+ENV HOSTS=powerpc64-unknown-linux-gnu
+ENV HOSTS=$HOSTS,powerpc64le-unknown-linux-gnu
+
+ENV RUST_CONFIGURE_ARGS --host=$HOSTS
+ENV SCRIPT python2.7 ../x.py dist --host $HOSTS --target $HOSTS
diff --git a/src/ci/docker/dist-s390x-linux-netbsd/Dockerfile b/src/ci/docker/dist-s390x-linux-netbsd/Dockerfile
index a59bc7012cacd..7350b11a69fc0 100644
--- a/src/ci/docker/dist-s390x-linux-netbsd/Dockerfile
+++ b/src/ci/docker/dist-s390x-linux-netbsd/Dockerfile
@@ -33,11 +33,8 @@ ENV \
     CC_x86_64_unknown_netbsd=x86_64-unknown-netbsd-gcc \
     CXX_x86_64_unknown_netbsd=x86_64-unknown-netbsd-g++
 
-ENV RUST_CONFIGURE_ARGS \
-        --host=x86_64-unknown-netbsd,s390x-unknown-linux-gnu
-ENV SCRIPT \
-      python2.7 ../x.py dist \
-        --host x86_64-unknown-netbsd \
-        --target x86_64-unknown-netbsd \
-        --host s390x-unknown-linux-gnu \
-        --target s390x-unknown-linux-gnu
+ENV HOSTS=x86_64-unknown-netbsd
+ENV HOSTS=$HOSTS,s390x-unknown-linux-gnu
+
+ENV RUST_CONFIGURE_ARGS --host=$HOSTS
+ENV SCRIPT python2.7 ../x.py dist --host $HOSTS --target $HOSTS
diff --git a/src/ci/docker/dist-x86-linux/Dockerfile b/src/ci/docker/dist-x86-linux/Dockerfile
new file mode 100644
index 0000000000000..283a4aaab56f8
--- /dev/null
+++ b/src/ci/docker/dist-x86-linux/Dockerfile
@@ -0,0 +1,80 @@
+FROM centos:5
+
+WORKDIR /build
+
+RUN yum upgrade -y && yum install -y \
+      curl \
+      bzip2 \
+      gcc \
+      make \
+      glibc-devel \
+      perl \
+      zlib-devel \
+      file \
+      xz \
+      which \
+      pkg-config \
+      wget \
+      autoconf \
+      gettext
+
+ENV PATH=/rustroot/bin:$PATH
+ENV LD_LIBRARY_PATH=/rustroot/lib64:/rustroot/lib
+WORKDIR /tmp
+
+# binutils < 2.22 has a bug where the 32-bit executables it generates
+# immediately segfault in Rust, so we need to install our own binutils.
+#
+# See https://github.com/rust-lang/rust/issues/20440 for more info
+COPY shared.sh build-binutils.sh /tmp/
+RUN ./build-binutils.sh
+
+# Need a newer version of gcc than centos has to compile LLVM nowadays
+COPY build-gcc.sh /tmp/
+RUN ./build-gcc.sh
+
+# We need a build of openssl which supports SNI to download artifacts from
+# static.rust-lang.org. This'll be used to link into libcurl below (and used
+# later as well), so build a copy of OpenSSL with dynamic libraries into our
+# generic root.
+COPY build-openssl.sh /tmp/
+RUN ./build-openssl.sh
+
+# The `curl` binary on CentOS doesn't support SNI which is needed for fetching
+# some https urls we have, so install a new version of libcurl + curl which is
+# using the openssl we just built previously.
+#
+# Note that we also disable a bunch of optional features of curl that we don't
+# really need.
+COPY build-curl.sh /tmp/
+RUN ./build-curl.sh
+
+# CentOS 5.5 has Python 2.4 by default, but LLVM needs 2.7+
+COPY build-python.sh /tmp/
+RUN ./build-python.sh
+
+# Apparently CentOS 5.5 desn't have `git` in yum, but we're gonna need it for
+# cloning, so download and build it here.
+COPY build-git.sh /tmp/
+RUN ./build-git.sh
+
+# libssh2 (a dependency of Cargo) requires cmake 2.8.11 or higher but CentOS
+# only has 2.6.4, so build our own
+COPY build-cmake.sh /tmp/
+RUN ./build-cmake.sh
+
+RUN curl -Lo /rustroot/dumb-init \
+      https://github.com/Yelp/dumb-init/releases/download/v1.2.0/dumb-init_1.2.0_amd64 && \
+      chmod +x /rustroot/dumb-init
+ENTRYPOINT ["/rustroot/dumb-init", "--"]
+
+ENV SCCACHE_DIGEST=7237e38e029342fa27b7ac25412cb9d52554008b12389727320bd533fd7f05b6a96d55485f305caf95e5c8f5f97c3313e10012ccad3e752aba2518f3522ba783
+RUN curl -L https://api.pub.build.mozilla.org/tooltool/sha512/$SCCACHE_DIGEST | \
+      xz --decompress | \
+      tar xf - -C /usr/local/bin --strip-components=1
+
+ENV HOSTS=i686-unknown-linux-gnu
+ENV HOSTS=$HOSTS,x86_64-unknown-linux-gnu
+
+ENV RUST_CONFIGURE_ARGS --host=$HOSTS
+ENV SCRIPT python2.7 ../x.py dist --host $HOSTS --target $HOSTS
diff --git a/src/ci/docker/dist-x86-linux/build-binutils.sh b/src/ci/docker/dist-x86-linux/build-binutils.sh
new file mode 100755
index 0000000000000..80aa1f2a01613
--- /dev/null
+++ b/src/ci/docker/dist-x86-linux/build-binutils.sh
@@ -0,0 +1,26 @@
+#!/bin/bash
+# Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+# file at the top-level directory of this distribution and at
+# http://rust-lang.org/COPYRIGHT.
+#
+# Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+# http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+# <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+# option. This file may not be copied, modified, or distributed
+# except according to those terms.
+
+set -ex
+
+source shared.sh
+
+curl https://ftp.gnu.org/gnu/binutils/binutils-2.25.1.tar.bz2 | tar xfj -
+
+mkdir binutils-build
+cd binutils-build
+hide_output ../binutils-2.25.1/configure --prefix=/rustroot
+hide_output make -j10
+hide_output make install
+
+cd ..
+rm -rf binutils-build
+rm -rf binutils-2.25.1
diff --git a/src/ci/docker/dist-x86-linux/build-cmake.sh b/src/ci/docker/dist-x86-linux/build-cmake.sh
new file mode 100755
index 0000000000000..82e46455cb0f0
--- /dev/null
+++ b/src/ci/docker/dist-x86-linux/build-cmake.sh
@@ -0,0 +1,25 @@
+#!/bin/bash
+# Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+# file at the top-level directory of this distribution and at
+# http://rust-lang.org/COPYRIGHT.
+#
+# Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+# http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+# <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+# option. This file may not be copied, modified, or distributed
+# except according to those terms.
+
+set -ex
+source shared.sh
+
+curl https://cmake.org/files/v3.6/cmake-3.6.3.tar.gz | tar xzf -
+
+mkdir cmake-build
+cd cmake-build
+hide_output ../cmake-3.6.3/configure --prefix=/rustroot
+hide_output make -j10
+hide_output make install
+
+cd ..
+rm -rf cmake-build
+rm -rf cmake-3.6.3
diff --git a/src/ci/docker/dist-x86-linux/build-curl.sh b/src/ci/docker/dist-x86-linux/build-curl.sh
new file mode 100755
index 0000000000000..b7d22755a571b
--- /dev/null
+++ b/src/ci/docker/dist-x86-linux/build-curl.sh
@@ -0,0 +1,43 @@
+#!/bin/bash
+# Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+# file at the top-level directory of this distribution and at
+# http://rust-lang.org/COPYRIGHT.
+#
+# Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+# http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+# <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+# option. This file may not be copied, modified, or distributed
+# except according to those terms.
+
+set -ex
+source shared.sh
+
+VERSION=7.51.0
+
+curl http://cool.haxx.se/download/curl-$VERSION.tar.bz2 | tar xjf -
+
+mkdir curl-build
+cd curl-build
+hide_output ../curl-$VERSION/configure \
+      --prefix=/rustroot \
+      --with-ssl=/rustroot \
+      --disable-sspi \
+      --disable-gopher \
+      --disable-smtp \
+      --disable-smb \
+      --disable-imap \
+      --disable-pop3 \
+      --disable-tftp \
+      --disable-telnet \
+      --disable-manual \
+      --disable-dict \
+      --disable-rtsp \
+      --disable-ldaps \
+      --disable-ldap
+hide_output make -j10
+hide_output make install
+
+cd ..
+rm -rf curl-build
+rm -rf curl-$VERSION
+yum erase -y curl
diff --git a/src/ci/docker/dist-x86-linux/build-gcc.sh b/src/ci/docker/dist-x86-linux/build-gcc.sh
new file mode 100755
index 0000000000000..06198eb0c97fc
--- /dev/null
+++ b/src/ci/docker/dist-x86-linux/build-gcc.sh
@@ -0,0 +1,31 @@
+#!/bin/bash
+# Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+# file at the top-level directory of this distribution and at
+# http://rust-lang.org/COPYRIGHT.
+#
+# Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+# http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+# <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+# option. This file may not be copied, modified, or distributed
+# except according to those terms.
+
+set -ex
+
+source shared.sh
+
+curl https://ftp.gnu.org/gnu/gcc/gcc-4.7.4/gcc-4.7.4.tar.bz2 | tar xjf -
+cd gcc-4.7.4
+./contrib/download_prerequisites
+mkdir ../gcc-build
+cd ../gcc-build
+hide_output ../gcc-4.7.4/configure \
+    --prefix=/rustroot \
+    --enable-languages=c,c++
+hide_output make -j10
+hide_output make install
+ln -nsf gcc /rustroot/bin/cc
+
+cd ..
+rm -rf gcc-build
+rm -rf gcc-4.7.4
+yum erase -y gcc binutils
diff --git a/src/ci/docker/dist-x86-linux/build-git.sh b/src/ci/docker/dist-x86-linux/build-git.sh
new file mode 100755
index 0000000000000..92fa66b496d93
--- /dev/null
+++ b/src/ci/docker/dist-x86-linux/build-git.sh
@@ -0,0 +1,24 @@
+#!/bin/bash
+# Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+# file at the top-level directory of this distribution and at
+# http://rust-lang.org/COPYRIGHT.
+#
+# Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+# http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+# <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+# option. This file may not be copied, modified, or distributed
+# except according to those terms.
+
+set -ex
+source shared.sh
+
+curl https://www.kernel.org/pub/software/scm/git/git-2.10.0.tar.gz | tar xzf -
+
+cd git-2.10.0
+make configure
+hide_output ./configure --prefix=/rustroot
+hide_output make -j10
+hide_output make install
+
+cd ..
+rm -rf git-2.10.0
diff --git a/src/ci/docker/dist-x86-linux/build-openssl.sh b/src/ci/docker/dist-x86-linux/build-openssl.sh
new file mode 100755
index 0000000000000..64b1abf82a827
--- /dev/null
+++ b/src/ci/docker/dist-x86-linux/build-openssl.sh
@@ -0,0 +1,27 @@
+#!/bin/bash
+# Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+# file at the top-level directory of this distribution and at
+# http://rust-lang.org/COPYRIGHT.
+#
+# Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+# http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+# <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+# option. This file may not be copied, modified, or distributed
+# except according to those terms.
+
+set -ex
+source shared.sh
+
+VERSION=1.0.2j
+
+curl https://www.openssl.org/source/openssl-$VERSION.tar.gz | tar xzf -
+
+cd openssl-$VERSION
+hide_output ./config --prefix=/rustroot shared -fPIC
+hide_output make -j10
+hide_output make install
+cd ..
+rm -rf openssl-$VERSION
+
+# Make the system cert collection available to the new install.
+ln -nsf /etc/pki/tls/cert.pem /rustroot/ssl/
diff --git a/src/ci/docker/dist-x86-linux/build-python.sh b/src/ci/docker/dist-x86-linux/build-python.sh
new file mode 100755
index 0000000000000..a7a450f3c8de7
--- /dev/null
+++ b/src/ci/docker/dist-x86-linux/build-python.sh
@@ -0,0 +1,30 @@
+#!/bin/bash
+# Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+# file at the top-level directory of this distribution and at
+# http://rust-lang.org/COPYRIGHT.
+#
+# Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+# http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+# <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+# option. This file may not be copied, modified, or distributed
+# except according to those terms.
+
+set -ex
+source shared.sh
+
+curl https://www.python.org/ftp/python/2.7.12/Python-2.7.12.tgz | \
+  tar xzf -
+
+mkdir python-build
+cd python-build
+
+# Gotta do some hackery to tell python about our custom OpenSSL build, but other
+# than that fairly normal.
+CFLAGS='-I /rustroot/include' LDFLAGS='-L /rustroot/lib -L /rustroot/lib64' \
+    hide_output ../Python-2.7.12/configure --prefix=/rustroot
+hide_output make -j10
+hide_output make install
+
+cd ..
+rm -rf python-build
+rm -rf Python-2.7.12
diff --git a/src/ci/docker/dist-x86-linux/shared.sh b/src/ci/docker/dist-x86-linux/shared.sh
new file mode 100644
index 0000000000000..97e6d2908cf8a
--- /dev/null
+++ b/src/ci/docker/dist-x86-linux/shared.sh
@@ -0,0 +1,25 @@
+# Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+# file at the top-level directory of this distribution and at
+# http://rust-lang.org/COPYRIGHT.
+#
+# Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+# http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+# <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+# option. This file may not be copied, modified, or distributed
+# except according to those terms.
+
+hide_output() {
+  set +x
+  on_err="
+echo ERROR: An error was encountered with the build.
+cat /tmp/build.log
+exit 1
+"
+  trap "$on_err" ERR
+  bash -c "while true; do sleep 30; echo \$(date) - building ...; done" &
+  PING_LOOP_PID=$!
+  $@ &> /tmp/build.log
+  trap - ERR
+  kill $PING_LOOP_PID
+  set -x
+}
diff --git a/src/ci/docker/emscripten/Dockerfile b/src/ci/docker/emscripten/Dockerfile
new file mode 100644
index 0000000000000..84e12eb6c3e11
--- /dev/null
+++ b/src/ci/docker/emscripten/Dockerfile
@@ -0,0 +1,41 @@
+FROM ubuntu:16.04
+
+RUN apt-get update && apt-get install -y --no-install-recommends \
+  g++ \
+  make \
+  file \
+  curl \
+  ca-certificates \
+  python \
+  git \
+  cmake \
+  sudo \
+  gdb \
+  xz-utils \
+  lib32stdc++6
+
+ENV SCCACHE_DIGEST=7237e38e029342fa27b7ac25412cb9d52554008b12389727320bd533fd7f05b6a96d55485f305caf95e5c8f5f97c3313e10012ccad3e752aba2518f3522ba783
+RUN curl -L https://api.pub.build.mozilla.org/tooltool/sha512/$SCCACHE_DIGEST | \
+      tar xJf - -C /usr/local/bin --strip-components=1
+
+RUN curl -OL https://github.com/Yelp/dumb-init/releases/download/v1.2.0/dumb-init_1.2.0_amd64.deb && \
+    dpkg -i dumb-init_*.deb && \
+    rm dumb-init_*.deb
+ENTRYPOINT ["/usr/bin/dumb-init", "--"]
+
+WORKDIR /tmp
+COPY build-emscripten.sh /tmp/
+RUN ./build-emscripten.sh
+ENV PATH=$PATH:/tmp/emsdk_portable
+ENV PATH=$PATH:/tmp/emsdk_portable/clang/tag-e1.37.1/build_tag-e1.37.1_32/bin
+ENV PATH=$PATH:/tmp/emsdk_portable/node/4.1.1_32bit/bin
+ENV PATH=$PATH:/tmp/emsdk_portable/emscripten/tag-1.37.1
+ENV EMSCRIPTEN=/tmp/emsdk_portable/emscripten/tag-1.37.1
+
+ENV RUST_CONFIGURE_ARGS --target=asmjs-unknown-emscripten
+
+# Run `emcc` first as it's got a prompt and doesn't actually do anything, after
+# that's done with do the real build.
+ENV SCRIPT emcc && \
+      python2.7 ../x.py test --target asmjs-unknown-emscripten
+
diff --git a/src/ci/docker/emscripten/build-emscripten.sh b/src/ci/docker/emscripten/build-emscripten.sh
new file mode 100755
index 0000000000000..88bf583007ce5
--- /dev/null
+++ b/src/ci/docker/emscripten/build-emscripten.sh
@@ -0,0 +1,36 @@
+#!/bin/bash
+# Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+# file at the top-level directory of this distribution and at
+# http://rust-lang.org/COPYRIGHT.
+#
+# Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+# http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+# <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+# option. This file may not be copied, modified, or distributed
+# except according to those terms.
+
+set -ex
+
+hide_output() {
+  set +x
+  on_err="
+echo ERROR: An error was encountered with the build.
+cat /tmp/build.log
+exit 1
+"
+  trap "$on_err" ERR
+  bash -c "while true; do sleep 30; echo \$(date) - building ...; done" &
+  PING_LOOP_PID=$!
+  $@ &> /tmp/build.log
+  trap - ERR
+  kill $PING_LOOP_PID
+  rm /tmp/build.log
+  set -x
+}
+
+curl https://s3.amazonaws.com/mozilla-games/emscripten/releases/emsdk-portable.tar.gz | \
+      tar xzf -
+source emsdk_portable/emsdk_env.sh
+hide_output emsdk update
+hide_output emsdk install --build=Release sdk-tag-1.37.1-32bit
+hide_output emsdk activate --build=Release sdk-tag-1.37.1-32bit
diff --git a/src/ci/docker/x86_64-musl/Dockerfile b/src/ci/docker/linux-tested-targets/Dockerfile
similarity index 56%
rename from src/ci/docker/x86_64-musl/Dockerfile
rename to src/ci/docker/linux-tested-targets/Dockerfile
index 11b85a6c8fdfb..7f95e17c7097a 100644
--- a/src/ci/docker/x86_64-musl/Dockerfile
+++ b/src/ci/docker/linux-tested-targets/Dockerfile
@@ -1,7 +1,7 @@
 FROM ubuntu:16.04
 
 RUN apt-get update && apt-get install -y --no-install-recommends \
-  g++ \
+  g++-multilib \
   make \
   file \
   curl \
@@ -11,10 +11,11 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
   cmake \
   xz-utils \
   sudo \
-  gdb
+  gdb \
+  patch
 
 WORKDIR /build/
-COPY build-musl.sh /build/
+COPY musl-libunwind-patch.patch build-musl.sh /build/
 RUN sh /build/build-musl.sh && rm -rf /build
 
 RUN curl -OL https://github.com/Yelp/dumb-init/releases/download/v1.2.0/dumb-init_1.2.0_amd64.deb && \
@@ -27,9 +28,17 @@ RUN curl -L https://api.pub.build.mozilla.org/tooltool/sha512/$SCCACHE_DIGEST |
       tar xJf - -C /usr/local/bin --strip-components=1
 
 ENV RUST_CONFIGURE_ARGS \
-      --target=x86_64-unknown-linux-musl \
-      --musl-root-x86_64=/musl-x86_64
-ENV PATH=$PATH:/musl-x86_64/bin
+      --target=x86_64-unknown-linux-musl,i686-unknown-linux-musl,i586-unknown-linux-gnu \
+      --musl-root-x86_64=/musl-x86_64 \
+      --musl-root-i686=/musl-i686
+
+# FIXME should also test i686-unknown-linux-musl
 ENV SCRIPT \
-      python2.7 ../x.py test --target x86_64-unknown-linux-musl && \
-      python2.7 ../x.py dist --target x86_64-unknown-linux-musl
+      python2.7 ../x.py test \
+          --target x86_64-unknown-linux-musl \
+          --target i586-unknown-linux-gnu \
+          && \
+      python2.7 ../x.py dist \
+          --target x86_64-unknown-linux-musl \
+          --target i686-unknown-linux-musl \
+          --target i586-unknown-linux-gnu
diff --git a/src/ci/docker/linux-tested-targets/build-musl.sh b/src/ci/docker/linux-tested-targets/build-musl.sh
new file mode 100644
index 0000000000000..2382605f9bd36
--- /dev/null
+++ b/src/ci/docker/linux-tested-targets/build-musl.sh
@@ -0,0 +1,64 @@
+#!/bin/sh
+# Copyright 2016 The Rust Project Developers. See the COPYRIGHT
+# file at the top-level directory of this distribution and at
+# http://rust-lang.org/COPYRIGHT.
+#
+# Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+# http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+# <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+# option. This file may not be copied, modified, or distributed
+# except according to those terms.
+
+set -ex
+
+export CFLAGS="-fPIC"
+MUSL=musl-1.1.14
+curl https://www.musl-libc.org/releases/$MUSL.tar.gz | tar xzf -
+cd $MUSL
+./configure --prefix=/musl-x86_64 --disable-shared
+make -j10
+make install
+make clean
+# for i686
+CFLAGS="$CFLAGS -m32" ./configure --prefix=/musl-i686 --disable-shared --target=i686
+make -j10
+make install
+cd ..
+
+# To build MUSL we're going to need a libunwind lying around, so acquire that
+# here and build it.
+curl -L https://github.com/llvm-mirror/llvm/archive/release_37.tar.gz | tar xzf -
+curl -L https://github.com/llvm-mirror/libunwind/archive/release_37.tar.gz | tar xzf -
+
+# Whoa what's this mysterious patch we're applying to libunwind! Why are we
+# swapping the values of ESP/EBP in libunwind?!
+#
+# Discovered in #35599 it turns out that the vanilla build of libunwind is not
+# suitable for unwinding 32-bit musl. After some investigation it ended up
+# looking like the register values for ESP/EBP were indeed incorrect (swapped)
+# in the source. Similar commits in libunwind (r280099 and r282589) have noticed
+# this for other platforms, and we just need to realize it for musl linux as
+# well.
+#
+# More technical info can be found at #35599
+cd libunwind-release_37
+patch -Np1 < /build/musl-libunwind-patch.patch
+cd ..
+
+mkdir libunwind-build
+cd libunwind-build
+cmake ../libunwind-release_37 -DLLVM_PATH=/build/llvm-release_37 \
+          -DLIBUNWIND_ENABLE_SHARED=0
+make -j10
+cp lib/libunwind.a /musl-x86_64/lib
+
+# (Note: the next cmake call doesn't fully override the previous cached one, so remove the cached
+# configuration manually. IOW, if don't do this or call make clean we'll end up building libunwind
+# for x86_64 again)
+rm -rf *
+# for i686
+CFLAGS="$CFLAGS -m32 -g" CXXFLAGS="$CXXFLAGS -m32 -g" cmake ../libunwind-release_37 \
+          -DLLVM_PATH=/build/llvm-release_37 \
+          -DLIBUNWIND_ENABLE_SHARED=0
+make -j10
+cp lib/libunwind.a /musl-i686/lib
diff --git a/src/ci/docker/linux-tested-targets/musl-libunwind-patch.patch b/src/ci/docker/linux-tested-targets/musl-libunwind-patch.patch
new file mode 100644
index 0000000000000..99cd685b72d17
--- /dev/null
+++ b/src/ci/docker/linux-tested-targets/musl-libunwind-patch.patch
@@ -0,0 +1,15 @@
+diff --git a/include/libunwind.h b/include/libunwind.h
+index c5b9633..1360eb2 100644
+--- a/include/libunwind.h
++++ b/include/libunwind.h
+@@ -151,8 +151,8 @@ enum {
+   UNW_X86_ECX = 1,
+   UNW_X86_EDX = 2,
+   UNW_X86_EBX = 3,
+-  UNW_X86_EBP = 4,
+-  UNW_X86_ESP = 5,
++  UNW_X86_ESP = 4,
++  UNW_X86_EBP = 5,
+   UNW_X86_ESI = 6,
+   UNW_X86_EDI = 7
+ };
diff --git a/src/ci/docker/run.sh b/src/ci/docker/run.sh
index 80f40d1ba4773..0ddab8c4160f4 100755
--- a/src/ci/docker/run.sh
+++ b/src/ci/docker/run.sh
@@ -51,5 +51,6 @@ exec docker \
   --env DEPLOY=$DEPLOY \
   --env LOCAL_USER_ID=`id -u` \
   --volume "$HOME/.cargo:/cargo" \
+  --rm \
   rust-ci \
   /checkout/src/ci/run.sh
diff --git a/src/ci/docker/x86_64-musl/build-musl.sh b/src/ci/docker/x86_64-musl/build-musl.sh
deleted file mode 100644
index 2bfbd646b75c8..0000000000000
--- a/src/ci/docker/x86_64-musl/build-musl.sh
+++ /dev/null
@@ -1,33 +0,0 @@
-#!/bin/sh
-# Copyright 2016 The Rust Project Developers. See the COPYRIGHT
-# file at the top-level directory of this distribution and at
-# http://rust-lang.org/COPYRIGHT.
-#
-# Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-# http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-# <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-# option. This file may not be copied, modified, or distributed
-# except according to those terms.
-
-set -ex
-
-export CFLAGS="-fPIC"
-MUSL=musl-1.1.14
-curl https://www.musl-libc.org/releases/$MUSL.tar.gz | tar xzf -
-cd $MUSL
-./configure --prefix=/musl-x86_64 --disable-shared
-make -j10
-make install
-make clean
-cd ..
-
-# To build MUSL we're going to need a libunwind lying around, so acquire that
-# here and build it.
-curl -L https://github.com/llvm-mirror/llvm/archive/release_37.tar.gz | tar xzf -
-curl -L https://github.com/llvm-mirror/libunwind/archive/release_37.tar.gz | tar xzf -
-mkdir libunwind-build
-cd libunwind-build
-cmake ../libunwind-release_37 -DLLVM_PATH=/build/llvm-release_37 \
-          -DLIBUNWIND_ENABLE_SHARED=0
-make -j10
-cp lib/libunwind.a /musl-x86_64/lib
diff --git a/src/ci/run.sh b/src/ci/run.sh
index 205228a7bccc8..3a2cc47df79bf 100755
--- a/src/ci/run.sh
+++ b/src/ci/run.sh
@@ -22,19 +22,6 @@ RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --enable-sccache"
 RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --enable-quiet-tests"
 RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --disable-manage-submodules"
 
-# FIXME: we shouldn't forcibly enable debug assertions and llvm assertions when
-#        `DEPLOY` is set because then we'll be shipping slower binaries. We
-#        should only set these for auto branches, but we need to make sure that
-#        if we disable this all the relevant platforms are still tested
-#        somewhere with debug and llvm assertions.
-RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --enable-debug-assertions"
-
-# In general we always want to run tests with LLVM assertions enabled, but not
-# all platforms currently support that, so we have an option to disable.
-if [ "$NO_LLVM_ASSERTIONS" = "" ]; then
-  RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --enable-llvm-assertions"
-fi
-
 # If we're deploying artifacts then we set the release channel, otherwise if
 # we're not deploying then we want to be sure to enable all assertions becauase
 # we'll be running tests
@@ -43,10 +30,19 @@ fi
 #        either automatically or manually.
 if [ "$DEPLOY" != "" ]; then
   RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --release-channel=nightly"
+  RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --enable-llvm-static-stdcpp"
 
   if [ "$NO_LLVM_ASSERTIONS" = "1" ]; then
     RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --disable-llvm-assertions"
   fi
+else
+  RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --enable-debug-assertions"
+
+  # In general we always want to run tests with LLVM assertions enabled, but not
+  # all platforms currently support that, so we have an option to disable.
+  if [ "$NO_LLVM_ASSERTIONS" = "" ]; then
+    RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --enable-llvm-assertions"
+  fi
 fi
 
 # We want to enable usage of the `src/vendor` dir as much as possible, but not
@@ -63,7 +59,7 @@ $SRC/configure $RUST_CONFIGURE_ARGS
 if [ "$TRAVIS_OS_NAME" = "osx" ]; then
     ncpus=$(sysctl -n hw.ncpu)
 else
-    ncpus=$(nproc)
+    ncpus=$(grep processor /proc/cpuinfo | wc -l)
 fi
 
 if [ ! -z "$SCRIPT" ]; then
diff --git a/src/jemalloc b/src/jemalloc
index e058ca661692a..11bfb0dcf85f7 160000
--- a/src/jemalloc
+++ b/src/jemalloc
@@ -1 +1 @@
-Subproject commit e058ca661692a8d01f8cf9d35939dfe3105ce968
+Subproject commit 11bfb0dcf85f7aa92abd30524bb1e42e18d108c6
diff --git a/src/libcollections/vec.rs b/src/libcollections/vec.rs
index 4b05f8062e8bc..c5b904c8a2f0e 100644
--- a/src/libcollections/vec.rs
+++ b/src/libcollections/vec.rs
@@ -1023,8 +1023,8 @@ impl<T> Vec<T> {
     /// Create a draining iterator that removes the specified range in the vector
     /// and yields the removed items.
     ///
-    /// Note 1: The element range is removed even if the iterator is not
-    /// consumed until the end.
+    /// Note 1: The element range is removed even if the iterator is only
+    /// partially consumed or not consumed at all.
     ///
     /// Note 2: It is unspecified how many elements are removed from the vector,
     /// if the `Drain` value is leaked.
diff --git a/src/libcompiler_builtins/build.rs b/src/libcompiler_builtins/build.rs
index ab9a71e1ec6a6..b9421d779b590 100644
--- a/src/libcompiler_builtins/build.rs
+++ b/src/libcompiler_builtins/build.rs
@@ -107,7 +107,6 @@ fn main() {
                      "apple_versioning.c",
                      "ashldi3.c",
                      "ashrdi3.c",
-                     "clear_cache.c",
                      "clzdi2.c",
                      "clzsi2.c",
                      "cmpdi2.c",
diff --git a/src/libproc_macro/lib.rs b/src/libproc_macro/lib.rs
index 93bc867462568..ab5962779feeb 100644
--- a/src/libproc_macro/lib.rs
+++ b/src/libproc_macro/lib.rs
@@ -39,9 +39,9 @@ extern crate syntax;
 use std::fmt;
 use std::str::FromStr;
 
-use syntax::ast;
+use syntax::errors::DiagnosticBuilder;
 use syntax::parse;
-use syntax::ptr::P;
+use syntax::tokenstream::TokenStream as TokenStream_;
 
 /// The main type provided by this crate, representing an abstract stream of
 /// tokens.
@@ -54,7 +54,7 @@ use syntax::ptr::P;
 /// time!
 #[stable(feature = "proc_macro_lib", since = "1.15.0")]
 pub struct TokenStream {
-    inner: Vec<P<ast::Item>>,
+    inner: TokenStream_,
 }
 
 /// Error returned from `TokenStream::from_str`.
@@ -77,17 +77,41 @@ pub struct LexError {
 #[doc(hidden)]
 pub mod __internal {
     use std::cell::Cell;
+    use std::rc::Rc;
 
     use syntax::ast;
     use syntax::ptr::P;
-    use syntax::parse::ParseSess;
-    use super::TokenStream;
+    use syntax::parse::{self, token, ParseSess};
+    use syntax::tokenstream::TokenStream as TokenStream_;
+
+    use super::{TokenStream, LexError};
 
     pub fn new_token_stream(item: P<ast::Item>) -> TokenStream {
-        TokenStream { inner: vec![item] }
+        TokenStream { inner: TokenStream_::from_tokens(vec![
+            token::Interpolated(Rc::new(token::NtItem(item)))
+        ])}
+    }
+
+    pub fn token_stream_wrap(inner: TokenStream_) -> TokenStream {
+        TokenStream {
+            inner: inner
+        }
+    }
+
+    pub fn token_stream_parse_items(stream: TokenStream) -> Result<Vec<P<ast::Item>>, LexError> {
+        with_parse_sess(move |sess| {
+            let mut parser = parse::new_parser_from_ts(sess, stream.inner);
+            let mut items = Vec::new();
+
+            while let Some(item) = try!(parser.parse_item().map_err(super::parse_to_lex_err)) {
+                items.push(item)
+            }
+
+            Ok(items)
+        })
     }
 
-    pub fn token_stream_items(stream: TokenStream) -> Vec<P<ast::Item>> {
+    pub fn token_stream_inner(stream: TokenStream) -> TokenStream_ {
         stream.inner
     }
 
@@ -96,6 +120,10 @@ pub mod __internal {
                                   trait_name: &str,
                                   expand: fn(TokenStream) -> TokenStream,
                                   attributes: &[&'static str]);
+
+        fn register_attr_proc_macro(&mut self,
+                                    name: &str,
+                                    expand: fn(TokenStream, TokenStream) -> TokenStream);
     }
 
     // Emulate scoped_thread_local!() here essentially
@@ -125,11 +153,17 @@ pub mod __internal {
         where F: FnOnce(&ParseSess) -> R
     {
         let p = CURRENT_SESS.with(|p| p.get());
-        assert!(!p.is_null());
+        assert!(!p.is_null(), "proc_macro::__internal::with_parse_sess() called \
+                               before set_parse_sess()!");
         f(unsafe { &*p })
     }
 }
 
+fn parse_to_lex_err(mut err: DiagnosticBuilder) -> LexError {
+    err.cancel();
+    LexError { _inner: () }
+}
+
 #[stable(feature = "proc_macro_lib", since = "1.15.0")]
 impl FromStr for TokenStream {
     type Err = LexError;
@@ -138,18 +172,10 @@ impl FromStr for TokenStream {
         __internal::with_parse_sess(|sess| {
             let src = src.to_string();
             let name = "<proc-macro source code>".to_string();
-            let mut parser = parse::new_parser_from_source_str(sess, name, src);
-            let mut ret = TokenStream { inner: Vec::new() };
-            loop {
-                match parser.parse_item() {
-                    Ok(Some(item)) => ret.inner.push(item),
-                    Ok(None) => return Ok(ret),
-                    Err(mut err) => {
-                        err.cancel();
-                        return Err(LexError { _inner: () })
-                    }
-                }
-            }
+            let tts = try!(parse::parse_tts_from_source_str(name, src, sess)
+                .map_err(parse_to_lex_err));
+
+            Ok(__internal::token_stream_wrap(TokenStream_::from_tts(tts)))
         })
     }
 }
@@ -157,11 +183,6 @@ impl FromStr for TokenStream {
 #[stable(feature = "proc_macro_lib", since = "1.15.0")]
 impl fmt::Display for TokenStream {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        for item in self.inner.iter() {
-            let item = syntax::print::pprust::item_to_string(item);
-            try!(f.write_str(&item));
-            try!(f.write_str("\n"));
-        }
-        Ok(())
+        self.inner.fmt(f)
     }
 }
diff --git a/src/librustc/hir/print.rs b/src/librustc/hir/print.rs
index 377f2ea26aba9..58c677fb507fe 100644
--- a/src/librustc/hir/print.rs
+++ b/src/librustc/hir/print.rs
@@ -13,6 +13,7 @@ pub use self::AnnNode::*;
 use syntax::abi::Abi;
 use syntax::ast;
 use syntax::codemap::{CodeMap, Spanned};
+use syntax::parse::ParseSess;
 use syntax::parse::lexer::comments;
 use syntax::print::pp::{self, break_offset, word, space, hardbreak};
 use syntax::print::pp::{Breaks, eof};
@@ -21,7 +22,6 @@ use syntax::print::pprust::{self as ast_pp, PrintState};
 use syntax::ptr::P;
 use syntax::symbol::keywords;
 use syntax_pos::{self, BytePos};
-use errors;
 
 use hir;
 use hir::{PatKind, RegionTyParamBound, TraitTyParamBound, TraitBoundModifier};
@@ -116,7 +116,7 @@ pub const default_columns: usize = 78;
 /// it can scan the input text for comments and literals to
 /// copy forward.
 pub fn print_crate<'a>(cm: &'a CodeMap,
-                       span_diagnostic: &errors::Handler,
+                       sess: &ParseSess,
                        krate: &hir::Crate,
                        filename: String,
                        input: &mut Read,
@@ -124,8 +124,7 @@ pub fn print_crate<'a>(cm: &'a CodeMap,
                        ann: &'a PpAnn,
                        is_expanded: bool)
                        -> io::Result<()> {
-    let mut s = State::new_from_input(cm, span_diagnostic, filename, input,
-                                      out, ann, is_expanded);
+    let mut s = State::new_from_input(cm, sess, filename, input, out, ann, is_expanded);
 
     // When printing the AST, we sometimes need to inject `#[no_std]` here.
     // Since you can't compile the HIR, it's not necessary.
@@ -137,16 +136,14 @@ pub fn print_crate<'a>(cm: &'a CodeMap,
 
 impl<'a> State<'a> {
     pub fn new_from_input(cm: &'a CodeMap,
-                          span_diagnostic: &errors::Handler,
+                          sess: &ParseSess,
                           filename: String,
                           input: &mut Read,
                           out: Box<Write + 'a>,
                           ann: &'a PpAnn,
                           is_expanded: bool)
                           -> State<'a> {
-        let (cmnts, lits) = comments::gather_comments_and_literals(span_diagnostic,
-                                                                   filename,
-                                                                   input);
+        let (cmnts, lits) = comments::gather_comments_and_literals(sess, filename, input);
 
         State::new(cm,
                    out,
diff --git a/src/librustc/lint/builtin.rs b/src/librustc/lint/builtin.rs
index 96fb168581b21..b0db3b75029fb 100644
--- a/src/librustc/lint/builtin.rs
+++ b/src/librustc/lint/builtin.rs
@@ -206,7 +206,7 @@ declare_lint! {
 
 declare_lint! {
     pub EXTRA_REQUIREMENT_IN_IMPL,
-    Warn,
+    Deny,
     "detects extra requirements in impls that were erroneously allowed"
 }
 
diff --git a/src/librustc/session/config.rs b/src/librustc/session/config.rs
index 104c851e057e6..7d8f7fcefe639 100644
--- a/src/librustc/session/config.rs
+++ b/src/librustc/session/config.rs
@@ -25,6 +25,7 @@ use lint;
 use middle::cstore;
 
 use syntax::ast::{self, IntTy, UintTy};
+use syntax::parse::token;
 use syntax::parse;
 use syntax::symbol::Symbol;
 use syntax::feature_gate::UnstableFeatures;
@@ -1259,7 +1260,7 @@ pub fn parse_cfgspecs(cfgspecs: Vec<String> ) -> ast::CrateConfig {
 
         let meta_item = panictry!(parser.parse_meta_item());
 
-        if !parser.reader.is_eof() {
+        if parser.token != token::Eof {
             early_error(ErrorOutputType::default(), &format!("invalid --cfg argument: {}", s))
         } else if meta_item.is_meta_item_list() {
             let msg =
diff --git a/src/librustc_driver/driver.rs b/src/librustc_driver/driver.rs
index b02551b814e7d..83dec4b0b77ab 100644
--- a/src/librustc_driver/driver.rs
+++ b/src/librustc_driver/driver.rs
@@ -681,6 +681,7 @@ pub fn phase_2_configure_and_expand<F>(sess: &Session,
             should_test: sess.opts.test,
             ..syntax::ext::expand::ExpansionConfig::default(crate_name.to_string())
         };
+
         let mut ecx = ExtCtxt::new(&sess.parse_sess, cfg, &mut resolver);
         let err_count = ecx.parse_sess.span_diagnostic.err_count();
 
@@ -740,17 +741,6 @@ pub fn phase_2_configure_and_expand<F>(sess: &Session,
          "checking for inline asm in case the target doesn't support it",
          || no_asm::check_crate(sess, &krate));
 
-    // Needs to go *after* expansion to be able to check the results of macro expansion.
-    time(time_passes, "complete gated feature checking", || {
-        sess.track_errors(|| {
-            syntax::feature_gate::check_crate(&krate,
-                                              &sess.parse_sess,
-                                              &sess.features.borrow(),
-                                              &attributes,
-                                              sess.opts.unstable_features);
-        })
-    })?;
-
     time(sess.time_passes(),
          "early lint checks",
          || lint::check_ast_crate(sess, &krate));
@@ -768,6 +758,17 @@ pub fn phase_2_configure_and_expand<F>(sess: &Session,
         Ok(())
     })?;
 
+    // Needs to go *after* expansion to be able to check the results of macro expansion.
+    time(time_passes, "complete gated feature checking", || {
+        sess.track_errors(|| {
+            syntax::feature_gate::check_crate(&krate,
+                                              &sess.parse_sess,
+                                              &sess.features.borrow(),
+                                              &attributes,
+                                              sess.opts.unstable_features);
+        })
+    })?;
+
     // Lower ast -> hir.
     let hir_forest = time(sess.time_passes(), "lowering ast -> hir", || {
         let hir_crate = lower_crate(sess, &krate, &mut resolver);
diff --git a/src/librustc_driver/lib.rs b/src/librustc_driver/lib.rs
index 25049b3d2badb..48eb6f68564f0 100644
--- a/src/librustc_driver/lib.rs
+++ b/src/librustc_driver/lib.rs
@@ -82,6 +82,7 @@ use rustc::util::common::time;
 
 use serialize::json::ToJson;
 
+use std::any::Any;
 use std::cmp::max;
 use std::cmp::Ordering::Equal;
 use std::default::Default;
@@ -1018,15 +1019,34 @@ fn parse_crate_attrs<'a>(sess: &'a Session, input: &Input) -> PResult<'a, Vec<as
     }
 }
 
+/// Runs `f` in a suitable thread for running `rustc`; returns a
+/// `Result` with either the return value of `f` or -- if a panic
+/// occurs -- the panic value.
+pub fn in_rustc_thread<F, R>(f: F) -> Result<R, Box<Any + Send>>
+    where F: FnOnce() -> R + Send + 'static,
+          R: Send + 'static,
+{
+    // Temporarily have stack size set to 16MB to deal with nom-using crates failing
+    const STACK_SIZE: usize = 16 * 1024 * 1024; // 16MB
+
+    let mut cfg = thread::Builder::new().name("rustc".to_string());
+
+    // FIXME: Hacks on hacks. If the env is trying to override the stack size
+    // then *don't* set it explicitly.
+    if env::var_os("RUST_MIN_STACK").is_none() {
+        cfg = cfg.stack_size(STACK_SIZE);
+    }
+
+    let thread = cfg.spawn(f);
+    thread.unwrap().join()
+}
+
 /// Run a procedure which will detect panics in the compiler and print nicer
 /// error messages rather than just failing the test.
 ///
 /// The diagnostic emitter yielded to the procedure should be used for reporting
 /// errors of the compiler.
 pub fn monitor<F: FnOnce() + Send + 'static>(f: F) {
-    // Temporarily have stack size set to 16MB to deal with nom-using crates failing
-    const STACK_SIZE: usize = 16 * 1024 * 1024; // 16MB
-
     struct Sink(Arc<Mutex<Vec<u8>>>);
     impl Write for Sink {
         fn write(&mut self, data: &[u8]) -> io::Result<usize> {
@@ -1040,20 +1060,12 @@ pub fn monitor<F: FnOnce() + Send + 'static>(f: F) {
     let data = Arc::new(Mutex::new(Vec::new()));
     let err = Sink(data.clone());
 
-    let mut cfg = thread::Builder::new().name("rustc".to_string());
-
-    // FIXME: Hacks on hacks. If the env is trying to override the stack size
-    // then *don't* set it explicitly.
-    if env::var_os("RUST_MIN_STACK").is_none() {
-        cfg = cfg.stack_size(STACK_SIZE);
-    }
-
-    let thread = cfg.spawn(move || {
-         io::set_panic(Some(box err));
-         f()
-     });
+    let result = in_rustc_thread(move || {
+        io::set_panic(Some(box err));
+        f()
+    });
 
-     if let Err(value) = thread.unwrap().join() {
+    if let Err(value) = result {
         // Thread panicked without emitting a fatal diagnostic
         if !value.is::<errors::FatalError>() {
             let emitter =
diff --git a/src/librustc_driver/pretty.rs b/src/librustc_driver/pretty.rs
index afacfb6e3f9fd..3c8a529bdaee8 100644
--- a/src/librustc_driver/pretty.rs
+++ b/src/librustc_driver/pretty.rs
@@ -838,7 +838,7 @@ pub fn print_after_parsing(sess: &Session,
                 debug!("pretty printing source code {:?}", s);
                 let sess = annotation.sess();
                 pprust::print_crate(sess.codemap(),
-                                    sess.diagnostic(),
+                                    &sess.parse_sess,
                                     krate,
                                     src_name.to_string(),
                                     &mut rdr,
@@ -896,7 +896,7 @@ pub fn print_after_hir_lowering<'tcx, 'a: 'tcx>(sess: &'a Session,
                     debug!("pretty printing source code {:?}", s);
                     let sess = annotation.sess();
                     pprust::print_crate(sess.codemap(),
-                                        sess.diagnostic(),
+                                        &sess.parse_sess,
                                         krate,
                                         src_name.to_string(),
                                         &mut rdr,
@@ -920,7 +920,7 @@ pub fn print_after_hir_lowering<'tcx, 'a: 'tcx>(sess: &'a Session,
                     debug!("pretty printing source code {:?}", s);
                     let sess = annotation.sess();
                     pprust_hir::print_crate(sess.codemap(),
-                                            sess.diagnostic(),
+                                            &sess.parse_sess,
                                             krate,
                                             src_name.to_string(),
                                             &mut rdr,
@@ -945,7 +945,7 @@ pub fn print_after_hir_lowering<'tcx, 'a: 'tcx>(sess: &'a Session,
                     let sess = annotation.sess();
                     let ast_map = annotation.ast_map().expect("--unpretty missing HIR map");
                     let mut pp_state = pprust_hir::State::new_from_input(sess.codemap(),
-                                                                         sess.diagnostic(),
+                                                                         &sess.parse_sess,
                                                                          src_name.to_string(),
                                                                          &mut rdr,
                                                                          box out,
diff --git a/src/librustc_metadata/creader.rs b/src/librustc_metadata/creader.rs
index 8f7b9c24cbf8a..161331b1728bc 100644
--- a/src/librustc_metadata/creader.rs
+++ b/src/librustc_metadata/creader.rs
@@ -578,6 +578,7 @@ impl<'a> CrateLoader<'a> {
         use proc_macro::__internal::Registry;
         use rustc_back::dynamic_lib::DynamicLibrary;
         use syntax_ext::deriving::custom::CustomDerive;
+        use syntax_ext::proc_macro_impl::AttrProcMacro;
 
         let path = match dylib {
             Some(dylib) => dylib,
@@ -613,6 +614,15 @@ impl<'a> CrateLoader<'a> {
                 );
                 self.0.push((Symbol::intern(trait_name), Rc::new(derive)));
             }
+
+            fn register_attr_proc_macro(&mut self,
+                                        name: &str,
+                                        expand: fn(TokenStream, TokenStream) -> TokenStream) {
+                let expand = SyntaxExtension::AttrProcMacro(
+                    Box::new(AttrProcMacro { inner: expand })
+                );
+                self.0.push((Symbol::intern(name), Rc::new(expand)));
+            }
         }
 
         let mut my_registrar = MyRegistrar(Vec::new());
diff --git a/src/librustc_metadata/cstore_impl.rs b/src/librustc_metadata/cstore_impl.rs
index 7cd26df0246ea..f6107bc135915 100644
--- a/src/librustc_metadata/cstore_impl.rs
+++ b/src/librustc_metadata/cstore_impl.rs
@@ -29,7 +29,7 @@ use rustc_back::PanicStrategy;
 
 use syntax::ast;
 use syntax::attr;
-use syntax::parse::new_parser_from_source_str;
+use syntax::parse::filemap_to_tts;
 use syntax::symbol::Symbol;
 use syntax_pos::{mk_sp, Span};
 use rustc::hir::svh::Svh;
@@ -399,19 +399,9 @@ impl<'tcx> CrateStore<'tcx> for cstore::CStore {
         let (name, def) = data.get_macro(id.index);
         let source_name = format!("<{} macros>", name);
 
-        // NB: Don't use parse_tts_from_source_str because it parses with quote_depth > 0.
-        let mut parser = new_parser_from_source_str(&sess.parse_sess, source_name, def.body);
-
-        let lo = parser.span.lo;
-        let body = match parser.parse_all_token_trees() {
-            Ok(body) => body,
-            Err(mut err) => {
-                err.emit();
-                sess.abort_if_errors();
-                unreachable!();
-            }
-        };
-        let local_span = mk_sp(lo, parser.prev_span.hi);
+        let filemap = sess.parse_sess.codemap().new_filemap(source_name, None, def.body);
+        let local_span = mk_sp(filemap.start_pos, filemap.end_pos);
+        let body = filemap_to_tts(&sess.parse_sess, filemap);
 
         // Mark the attrs as used
         let attrs = data.get_item_attrs(id.index);
diff --git a/src/librustc_resolve/build_reduced_graph.rs b/src/librustc_resolve/build_reduced_graph.rs
index 5be21bc62c56c..5e9856878865a 100644
--- a/src/librustc_resolve/build_reduced_graph.rs
+++ b/src/librustc_resolve/build_reduced_graph.rs
@@ -143,7 +143,7 @@ impl<'a> Resolver<'a> {
                 let is_prelude = attr::contains_name(&item.attrs, "prelude_import");
 
                 match view_path.node {
-                    ViewPathSimple(binding, ref full_path) => {
+                    ViewPathSimple(mut binding, ref full_path) => {
                         let mut source = full_path.segments.last().unwrap().identifier;
                         let source_name = source.name;
                         if source_name == "mod" || source_name == "self" {
@@ -157,6 +157,9 @@ impl<'a> Resolver<'a> {
                                 ModuleKind::Block(..) => unreachable!(),
                             };
                             source.name = crate_name;
+                            if binding.name == "$crate" {
+                                binding.name = crate_name;
+                            }
 
                             self.session.struct_span_warn(item.span, "`$crate` may not be imported")
                                 .note("`use $crate;` was erroneously allowed and \
diff --git a/src/librustc_resolve/lib.rs b/src/librustc_resolve/lib.rs
index 56e8c75b859a1..971b91ea313f3 100644
--- a/src/librustc_resolve/lib.rs
+++ b/src/librustc_resolve/lib.rs
@@ -61,12 +61,13 @@ use syntax::ast::{FnDecl, ForeignItem, ForeignItemKind, Generics};
 use syntax::ast::{Item, ItemKind, ImplItem, ImplItemKind};
 use syntax::ast::{Local, Mutability, Pat, PatKind, Path};
 use syntax::ast::{QSelf, TraitItemKind, TraitRef, Ty, TyKind};
-use syntax::feature_gate::{emit_feature_err, GateIssue};
+use syntax::feature_gate::{feature_err, emit_feature_err, GateIssue};
 
 use syntax_pos::{Span, DUMMY_SP, MultiSpan};
 use errors::DiagnosticBuilder;
 
 use std::cell::{Cell, RefCell};
+use std::cmp;
 use std::fmt;
 use std::mem::replace;
 use std::rc::Rc;
@@ -1123,6 +1124,12 @@ pub struct Resolver<'a> {
 
     // Avoid duplicated errors for "name already defined".
     name_already_seen: FxHashMap<Name, Span>,
+
+    // If `#![feature(proc_macro)]` is set
+    proc_macro_enabled: bool,
+
+    // A set of procedural macros imported by `#[macro_use]` that have already been warned about
+    warned_proc_macros: FxHashSet<Name>,
 }
 
 pub struct ResolverArenas<'a> {
@@ -1227,6 +1234,8 @@ impl<'a> Resolver<'a> {
         invocations.insert(Mark::root(),
                            arenas.alloc_invocation_data(InvocationData::root(graph_root)));
 
+        let features = session.features.borrow();
+
         Resolver {
             session: session,
 
@@ -1284,7 +1293,9 @@ impl<'a> Resolver<'a> {
                 span: DUMMY_SP,
                 vis: ty::Visibility::Public,
             }),
-            use_extern_macros: session.features.borrow().use_extern_macros,
+
+            // `#![feature(proc_macro)]` implies `#[feature(extern_macros)]`
+            use_extern_macros: features.use_extern_macros || features.proc_macro,
 
             exported_macros: Vec::new(),
             crate_loader: crate_loader,
@@ -1296,6 +1307,8 @@ impl<'a> Resolver<'a> {
             invocations: invocations,
             name_already_seen: FxHashMap(),
             whitelisted_legacy_custom_derives: Vec::new(),
+            proc_macro_enabled: features.proc_macro,
+            warned_proc_macros: FxHashSet(),
         }
     }
 
@@ -1525,6 +1538,8 @@ impl<'a> Resolver<'a> {
 
         debug!("(resolving item) resolving {}", name);
 
+        self.check_proc_macro_attrs(&item.attrs);
+
         match item.node {
             ItemKind::Enum(_, ref generics) |
             ItemKind::Ty(_, ref generics) |
@@ -1554,6 +1569,8 @@ impl<'a> Resolver<'a> {
                         walk_list!(this, visit_ty_param_bound, bounds);
 
                         for trait_item in trait_items {
+                            this.check_proc_macro_attrs(&trait_item.attrs);
+
                             match trait_item.node {
                                 TraitItemKind::Const(_, ref default) => {
                                     // Only impose the restrictions of
@@ -1738,6 +1755,7 @@ impl<'a> Resolver<'a> {
                 this.with_self_rib(Def::SelfTy(trait_id, Some(item_def_id)), |this| {
                     this.with_current_self_type(self_type, |this| {
                         for impl_item in impl_items {
+                            this.check_proc_macro_attrs(&impl_item.attrs);
                             this.resolve_visibility(&impl_item.vis);
                             match impl_item.node {
                                 ImplItemKind::Const(..) => {
@@ -3184,6 +3202,31 @@ impl<'a> Resolver<'a> {
         let msg = "`self` no longer imports values".to_string();
         self.session.add_lint(lint::builtin::LEGACY_IMPORTS, id, span, msg);
     }
+
+    fn check_proc_macro_attrs(&mut self, attrs: &[ast::Attribute]) {
+        if self.proc_macro_enabled { return; }
+
+        for attr in attrs {
+            let maybe_binding = self.builtin_macros.get(&attr.name()).cloned().or_else(|| {
+                let ident = Ident::with_empty_ctxt(attr.name());
+                self.resolve_lexical_macro_path_segment(ident, MacroNS, None).ok()
+            });
+
+            if let Some(binding) = maybe_binding {
+                if let SyntaxExtension::AttrProcMacro(..) = *binding.get_macro(self) {
+                    attr::mark_known(attr);
+
+                    let msg = "attribute procedural macros are experimental";
+                    let feature = "proc_macro";
+
+                    feature_err(&self.session.parse_sess, feature,
+                                attr.span, GateIssue::Language, msg)
+                        .span_note(binding.span, "procedural macro imported here")
+                        .emit();
+                }
+            }
+        }
+    }
 }
 
 fn is_struct_like(def: Def) -> bool {
@@ -3224,7 +3267,7 @@ fn show_candidates(session: &mut DiagnosticBuilder,
                    better: bool) {
     // don't show more than MAX_CANDIDATES results, so
     // we're consistent with the trait suggestions
-    const MAX_CANDIDATES: usize = 5;
+    const MAX_CANDIDATES: usize = 4;
 
     // we want consistent results across executions, but candidates are produced
     // by iterating through a hash map, so make sure they are ordered:
@@ -3237,21 +3280,21 @@ fn show_candidates(session: &mut DiagnosticBuilder,
         1 => " is found in another module, you can import it",
         _ => "s are found in other modules, you can import them",
     };
-    session.help(&format!("possible {}candidate{} into scope:", better, msg_diff));
-
-    let count = path_strings.len() as isize - MAX_CANDIDATES as isize + 1;
-    for (idx, path_string) in path_strings.iter().enumerate() {
-        if idx == MAX_CANDIDATES - 1 && count > 1 {
-            session.help(
-                &format!("  and {} other candidates", count).to_string(),
-            );
-            break;
-        } else {
-            session.help(
-                &format!("  `use {};`", path_string).to_string(),
-            );
-        }
-    }
+
+    let end = cmp::min(MAX_CANDIDATES, path_strings.len());
+    session.help(&format!("possible {}candidate{} into scope:{}{}",
+                          better,
+                          msg_diff,
+                          &path_strings[0..end].iter().map(|candidate| {
+                              format!("\n  `use {};`", candidate)
+                          }).collect::<String>(),
+                          if path_strings.len() > MAX_CANDIDATES {
+                              format!("\nand {} other candidates",
+                                      path_strings.len() - MAX_CANDIDATES)
+                          } else {
+                              "".to_owned()
+                          }
+                          ));
 }
 
 /// A somewhat inefficient routine to obtain the name of a module.
diff --git a/src/librustc_resolve/macros.rs b/src/librustc_resolve/macros.rs
index 403797b6d318e..9b7d6f33a7f3b 100644
--- a/src/librustc_resolve/macros.rs
+++ b/src/librustc_resolve/macros.rs
@@ -27,7 +27,7 @@ use syntax::ext::base::{NormalTT, Resolver as SyntaxResolver, SyntaxExtension};
 use syntax::ext::expand::{Expansion, mark_tts};
 use syntax::ext::hygiene::Mark;
 use syntax::ext::tt::macro_rules;
-use syntax::feature_gate::{emit_feature_err, GateIssue};
+use syntax::feature_gate::{emit_feature_err, GateIssue, is_builtin_attr};
 use syntax::fold::{self, Folder};
 use syntax::ptr::P;
 use syntax::symbol::keywords;
@@ -183,6 +183,10 @@ impl<'a> base::Resolver for Resolver<'a> {
                 },
                 None => {}
             }
+
+            if self.proc_macro_enabled && !is_builtin_attr(&attrs[i]) {
+                return Some(attrs.remove(i));
+            }
         }
         None
     }
@@ -373,6 +377,10 @@ impl<'a> Resolver<'a> {
             let resolution = self.resolve_lexical_macro_path_segment(ident, MacroNS, Some(span));
             let (legacy_resolution, resolution) = match (legacy_resolution, resolution) {
                 (Some(legacy_resolution), Ok(resolution)) => (legacy_resolution, resolution),
+                (Some(MacroBinding::Modern(binding)), Err(_)) => {
+                    self.err_if_macro_use_proc_macro(ident.name, span, binding);
+                    continue
+                },
                 _ => continue,
             };
             let (legacy_span, participle) = match legacy_resolution {
@@ -469,4 +477,37 @@ impl<'a> Resolver<'a> {
             self.exported_macros.push(def);
         }
     }
+
+    /// Error if `ext` is a Macros 1.1 procedural macro being imported by `#[macro_use]`
+    fn err_if_macro_use_proc_macro(&mut self, name: Name, use_span: Span,
+                                   binding: &NameBinding<'a>) {
+        use self::SyntaxExtension::*;
+
+        let krate = binding.def().def_id().krate;
+
+        // Plugin-based syntax extensions are exempt from this check
+        if krate == BUILTIN_MACROS_CRATE { return; }
+
+        let ext = binding.get_macro(self);
+
+        match *ext {
+            // If `ext` is a procedural macro, check if we've already warned about it
+            AttrProcMacro(_) | ProcMacro(_) => if !self.warned_proc_macros.insert(name) { return; },
+            _ => return,
+        }
+
+        let warn_msg = match *ext {
+            AttrProcMacro(_) => "attribute procedural macros cannot be \
+                                 imported with `#[macro_use]`",
+            ProcMacro(_) => "procedural macros cannot be imported with `#[macro_use]`",
+            _ => return,
+        };
+
+        let crate_name = self.session.cstore.crate_name(krate);
+
+        self.session.struct_span_err(use_span, warn_msg)
+            .help(&format!("instead, import the procedural macro like any other item: \
+                             `use {}::{};`", crate_name, name))
+            .emit();
+    }
 }
diff --git a/src/librustc_save_analysis/span_utils.rs b/src/librustc_save_analysis/span_utils.rs
index 448bb2e761749..89525b27ed36a 100644
--- a/src/librustc_save_analysis/span_utils.rs
+++ b/src/librustc_save_analysis/span_utils.rs
@@ -17,9 +17,9 @@ use std::env;
 use std::path::Path;
 
 use syntax::ast;
-use syntax::parse::lexer::{self, Reader, StringReader};
+use syntax::parse::filemap_to_tts;
+use syntax::parse::lexer::{self, StringReader};
 use syntax::parse::token::{self, Token};
-use syntax::parse::parser::Parser;
 use syntax::symbol::keywords;
 use syntax::tokenstream::TokenTree;
 use syntax_pos::*;
@@ -85,14 +85,13 @@ impl<'a> SpanUtils<'a> {
         let filemap = self.sess
                           .codemap()
                           .new_filemap(String::from("<anon-dxr>"), None, self.snippet(span));
-        let s = self.sess;
-        lexer::StringReader::new(s.diagnostic(), filemap)
+        lexer::StringReader::new(&self.sess.parse_sess, filemap)
     }
 
     fn span_to_tts(&self, span: Span) -> Vec<TokenTree> {
-        let srdr = self.retokenise_span(span);
-        let mut p = Parser::new(&self.sess.parse_sess, Box::new(srdr), None, false);
-        p.parse_all_token_trees().expect("Couldn't re-parse span")
+        let filename = String::from("<anon-dxr>");
+        let filemap = self.sess.codemap().new_filemap(filename, None, self.snippet(span));
+        filemap_to_tts(&self.sess.parse_sess, filemap)
     }
 
     // Re-parses a path and returns the span for the last identifier in the path
diff --git a/src/librustc_trans/back/write.rs b/src/librustc_trans/back/write.rs
index 96045c6c079a7..b3a2d66a07c11 100644
--- a/src/librustc_trans/back/write.rs
+++ b/src/librustc_trans/back/write.rs
@@ -667,7 +667,9 @@ pub fn run_passes(sess: &Session,
 
     // Sanity check
     assert!(trans.modules.len() == sess.opts.cg.codegen_units ||
-            sess.opts.debugging_opts.incremental.is_some());
+            sess.opts.debugging_opts.incremental.is_some() ||
+            !sess.opts.output_types.should_trans() ||
+            sess.opts.debugging_opts.no_trans);
 
     let tm = create_target_machine(sess);
 
@@ -756,7 +758,7 @@ pub fn run_passes(sess: &Session,
     //       the compiler decides the number of codegen units (and will
     //       potentially create hundreds of them).
     let num_workers = work_items.len() - 1;
-    if num_workers == 1 {
+    if num_workers <= 1 {
         run_work_singlethreaded(sess, &trans.exported_symbols, work_items);
     } else {
         run_work_multithreaded(sess, work_items, num_workers);
diff --git a/src/librustc_trans/base.rs b/src/librustc_trans/base.rs
index 4cdde24ed48b5..d006dccbccc58 100644
--- a/src/librustc_trans/base.rs
+++ b/src/librustc_trans/base.rs
@@ -1145,6 +1145,23 @@ pub fn trans_crate<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
     };
     let no_builtins = attr::contains_name(&krate.attrs, "no_builtins");
 
+    // Skip crate items and just output metadata in -Z no-trans mode.
+    if tcx.sess.opts.debugging_opts.no_trans ||
+       !tcx.sess.opts.output_types.should_trans() {
+        let empty_exported_symbols = ExportedSymbols::empty();
+        let linker_info = LinkerInfo::new(&shared_ccx, &empty_exported_symbols);
+        return CrateTranslation {
+            modules: vec![],
+            metadata_module: metadata_module,
+            link: link_meta,
+            metadata: metadata,
+            exported_symbols: empty_exported_symbols,
+            no_builtins: no_builtins,
+            linker_info: linker_info,
+            windows_subsystem: None,
+        };
+    }
+
     // Run the translation item collector and partition the collected items into
     // codegen units.
     let (codegen_units, symbol_map) = collect_and_partition_translation_items(&shared_ccx);
@@ -1181,22 +1198,6 @@ pub fn trans_crate<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
 
     assert_module_sources::assert_module_sources(tcx, &modules);
 
-    // Skip crate items and just output metadata in -Z no-trans mode.
-    if tcx.sess.opts.debugging_opts.no_trans ||
-       tcx.sess.opts.output_types.contains_key(&config::OutputType::Metadata) {
-        let linker_info = LinkerInfo::new(&shared_ccx, &ExportedSymbols::empty());
-        return CrateTranslation {
-            modules: modules,
-            metadata_module: metadata_module,
-            link: link_meta,
-            metadata: metadata,
-            exported_symbols: ExportedSymbols::empty(),
-            no_builtins: no_builtins,
-            linker_info: linker_info,
-            windows_subsystem: None,
-        };
-    }
-
     // Instantiate translation items without filling out definitions yet...
     for ccx in crate_context_list.iter_need_trans() {
         let cgu = ccx.codegen_unit();
diff --git a/src/librustc_typeck/coherence/overlap.rs b/src/librustc_typeck/coherence/overlap.rs
index 08293c1d874a8..7890ae20ec26c 100644
--- a/src/librustc_typeck/coherence/overlap.rs
+++ b/src/librustc_typeck/coherence/overlap.rs
@@ -102,6 +102,7 @@ impl<'cx, 'tcx, 'v> ItemLikeVisitor<'v> for OverlapChecker<'cx, 'tcx> {
         match item.node {
             hir::ItemEnum(..) |
             hir::ItemStruct(..) |
+            hir::ItemTrait(..) |
             hir::ItemUnion(..) => {
                 let type_def_id = self.tcx.map.local_def_id(item.id);
                 self.check_for_overlapping_inherent_impls(type_def_id);
diff --git a/src/librustc_typeck/collect.rs b/src/librustc_typeck/collect.rs
index e13434db5d886..d403ac4343531 100644
--- a/src/librustc_typeck/collect.rs
+++ b/src/librustc_typeck/collect.rs
@@ -1675,7 +1675,6 @@ fn is_unsized<'gcx: 'tcx, 'tcx>(astconv: &AstConv<'gcx, 'tcx>,
     for ab in ast_bounds {
         if let &hir::TraitTyParamBound(ref ptr, hir::TraitBoundModifier::Maybe) = ab  {
             if unbound.is_none() {
-                assert!(ptr.bound_lifetimes.is_empty());
                 unbound = Some(ptr.trait_ref.clone());
             } else {
                 span_err!(tcx.sess, span, E0203,
diff --git a/src/librustdoc/html/highlight.rs b/src/librustdoc/html/highlight.rs
index a031be8b3c2be..0629e93e7ef5d 100644
--- a/src/librustdoc/html/highlight.rs
+++ b/src/librustdoc/html/highlight.rs
@@ -27,7 +27,7 @@ use std::io;
 use std::io::prelude::*;
 
 use syntax::codemap::CodeMap;
-use syntax::parse::lexer::{self, Reader, TokenAndSpan};
+use syntax::parse::lexer::{self, TokenAndSpan};
 use syntax::parse::token;
 use syntax::parse;
 use syntax_pos::Span;
@@ -42,8 +42,7 @@ pub fn render_with_highlighting(src: &str, class: Option<&str>, id: Option<&str>
     let mut out = Vec::new();
     write_header(class, id, &mut out).unwrap();
 
-    let mut classifier = Classifier::new(lexer::StringReader::new(&sess.span_diagnostic, fm),
-                                         sess.codemap());
+    let mut classifier = Classifier::new(lexer::StringReader::new(&sess, fm), sess.codemap());
     if let Err(_) = classifier.write_source(&mut out) {
         return format!("<pre>{}</pre>", src);
     }
@@ -63,8 +62,7 @@ pub fn render_inner_with_highlighting(src: &str) -> io::Result<String> {
     let fm = sess.codemap().new_filemap("<stdin>".to_string(), None, src.to_string());
 
     let mut out = Vec::new();
-    let mut classifier = Classifier::new(lexer::StringReader::new(&sess.span_diagnostic, fm),
-                                         sess.codemap());
+    let mut classifier = Classifier::new(lexer::StringReader::new(&sess, fm), sess.codemap());
     classifier.write_source(&mut out)?;
 
     Ok(String::from_utf8_lossy(&out).into_owned())
@@ -185,10 +183,10 @@ impl<'a> Classifier<'a> {
                 Ok(tas) => tas,
                 Err(_) => {
                     self.lexer.emit_fatal_errors();
-                    self.lexer.span_diagnostic.struct_warn("Backing out of syntax highlighting")
-                                              .note("You probably did not intend to render this \
-                                                     as a rust code-block")
-                                              .emit();
+                    self.lexer.sess.span_diagnostic
+                        .struct_warn("Backing out of syntax highlighting")
+                        .note("You probably did not intend to render this as a rust code-block")
+                        .emit();
                     return Err(io::Error::new(io::ErrorKind::Other, ""));
                 }
             };
diff --git a/src/librustdoc/test.rs b/src/librustdoc/test.rs
index 26f331ac7d1a4..1f224cac9e91f 100644
--- a/src/librustdoc/test.rs
+++ b/src/librustdoc/test.rs
@@ -29,7 +29,7 @@ use rustc::session::config::{OutputType, OutputTypes, Externs};
 use rustc::session::search_paths::{SearchPaths, PathKind};
 use rustc_back::dynamic_lib::DynamicLibrary;
 use rustc_back::tempdir::TempDir;
-use rustc_driver::{driver, Compilation};
+use rustc_driver::{self, driver, Compilation};
 use rustc_driver::driver::phase_2_configure_and_expand;
 use rustc_metadata::cstore::CStore;
 use rustc_resolve::MakeGlobMap;
@@ -429,19 +429,26 @@ impl Collector {
                 should_panic: testing::ShouldPanic::No,
             },
             testfn: testing::DynTestFn(box move |()| {
-                runtest(&test,
-                        &cratename,
-                        cfgs,
-                        libs,
-                        externs,
-                        should_panic,
-                        no_run,
-                        as_test_harness,
-                        compile_fail,
-                        error_codes,
-                        &opts,
-                        maybe_sysroot);
-            })
+                match {
+                    rustc_driver::in_rustc_thread(move || {
+                        runtest(&test,
+                                &cratename,
+                                cfgs,
+                                libs,
+                                externs,
+                                should_panic,
+                                no_run,
+                                as_test_harness,
+                                compile_fail,
+                                error_codes,
+                                &opts,
+                                maybe_sysroot)
+                    })
+                } {
+                    Ok(()) => (),
+                    Err(err) => panic::resume_unwind(err),
+                }
+            }),
         });
     }
 
diff --git a/src/libstd/net/test.rs b/src/libstd/net/test.rs
index 3f2eacda7d60e..aec3d901ece60 100644
--- a/src/libstd/net/test.rs
+++ b/src/libstd/net/test.rs
@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#[allow(dead_code)] // not used on emscripten
+#![allow(warnings)] // not used on emscripten
 
 use env;
 use net::{SocketAddr, SocketAddrV4, SocketAddrV6, Ipv4Addr, Ipv6Addr, ToSocketAddrs};
diff --git a/src/libstd/num.rs b/src/libstd/num.rs
index d1c2fc3d3fce9..5f83d077a1368 100644
--- a/src/libstd/num.rs
+++ b/src/libstd/num.rs
@@ -172,6 +172,7 @@ mod tests {
 
     macro_rules! test_checked_next_power_of_two {
         ($test_name:ident, $T:ident) => (
+            #[cfg_attr(target_os = "emscripten", ignore)] // FIXME(#39119)
             fn $test_name() {
                 #![test]
                 assert_eq!((0 as $T).checked_next_power_of_two(), Some(1));
diff --git a/src/libstd/thread/mod.rs b/src/libstd/thread/mod.rs
index a2039db0e40c3..07a9b4bed9920 100644
--- a/src/libstd/thread/mod.rs
+++ b/src/libstd/thread/mod.rs
@@ -491,9 +491,12 @@ pub fn panicking() -> bool {
 /// Puts the current thread to sleep for the specified amount of time.
 ///
 /// The thread may sleep longer than the duration specified due to scheduling
-/// specifics or platform-dependent functionality. Note that on unix platforms
-/// this function will not return early due to a signal being received or a
-/// spurious wakeup.
+/// specifics or platform-dependent functionality.
+///
+/// # Platform behavior
+///
+/// On Unix platforms this function will not return early due to a
+/// signal being received or a spurious wakeup.
 ///
 /// # Examples
 ///
diff --git a/src/libsyntax/ext/base.rs b/src/libsyntax/ext/base.rs
index 68d261c64f83c..edf74e1fe19f1 100644
--- a/src/libsyntax/ext/base.rs
+++ b/src/libsyntax/ext/base.rs
@@ -615,9 +615,7 @@ impl<'a> ExtCtxt<'a> {
 
     pub fn new_parser_from_tts(&self, tts: &[tokenstream::TokenTree])
         -> parser::Parser<'a> {
-        let mut parser = parse::tts_to_parser(self.parse_sess, tts.to_vec());
-        parser.allow_interpolated_tts = false; // FIXME(jseyfried) `quote!` can't handle these yet
-        parser
+        parse::tts_to_parser(self.parse_sess, tts.to_vec())
     }
     pub fn codemap(&self) -> &'a CodeMap { self.parse_sess.codemap() }
     pub fn parse_sess(&self) -> &'a parse::ParseSess { self.parse_sess }
diff --git a/src/libsyntax/ext/expand.rs b/src/libsyntax/ext/expand.rs
index 26e731e1a5ecb..d748eec73e850 100644
--- a/src/libsyntax/ext/expand.rs
+++ b/src/libsyntax/ext/expand.rs
@@ -21,7 +21,7 @@ use ext::base::*;
 use feature_gate::{self, Features};
 use fold;
 use fold::*;
-use parse::{ParseSess, DirectoryOwnership, PResult, lexer};
+use parse::{ParseSess, DirectoryOwnership, PResult, filemap_to_tts};
 use parse::parser::Parser;
 use parse::token;
 use print::pprust;
@@ -364,7 +364,9 @@ impl<'a, 'b> MacroExpander<'a, 'b> {
                 kind.expect_from_annotatables(items)
             }
             SyntaxExtension::AttrProcMacro(ref mac) => {
-                let attr_toks = TokenStream::from_tts(tts_for_attr(&attr, &self.cx.parse_sess));
+                let attr_toks = TokenStream::from_tts(tts_for_attr_args(&attr,
+                                                                        &self.cx.parse_sess));
+
                 let item_toks = TokenStream::from_tts(tts_for_item(&item, &self.cx.parse_sess));
 
                 let tok_result = mac.expand(self.cx, attr.span, attr_toks, item_toks);
@@ -640,17 +642,35 @@ fn tts_for_item(item: &Annotatable, parse_sess: &ParseSess) -> Vec<TokenTree> {
     string_to_tts(text, parse_sess)
 }
 
-fn tts_for_attr(attr: &ast::Attribute, parse_sess: &ParseSess) -> Vec<TokenTree> {
-    string_to_tts(pprust::attr_to_string(attr), parse_sess)
+fn tts_for_attr_args(attr: &ast::Attribute, parse_sess: &ParseSess) -> Vec<TokenTree> {
+    use ast::MetaItemKind::*;
+    use print::pp::Breaks;
+    use print::pprust::PrintState;
+
+    let token_string = match attr.value.node {
+        // For `#[foo]`, an empty token
+        Word => return vec![],
+        // For `#[foo(bar, baz)]`, returns `(bar, baz)`
+        List(ref items) => pprust::to_string(|s| {
+            s.popen()?;
+            s.commasep(Breaks::Consistent,
+                       &items[..],
+                       |s, i| s.print_meta_list_item(&i))?;
+            s.pclose()
+        }),
+        // For `#[foo = "bar"]`, returns `= "bar"`
+        NameValue(ref lit) => pprust::to_string(|s| {
+            s.word_space("=")?;
+            s.print_literal(lit)
+        }),
+    };
+
+    string_to_tts(token_string, parse_sess)
 }
 
 fn string_to_tts(text: String, parse_sess: &ParseSess) -> Vec<TokenTree> {
-    let filemap = parse_sess.codemap()
-                            .new_filemap(String::from("<macro expansion>"), None, text);
-
-    let lexer = lexer::StringReader::new(&parse_sess.span_diagnostic, filemap);
-    let mut parser = Parser::new(parse_sess, Box::new(lexer), None, false);
-    panictry!(parser.parse_all_token_trees())
+    let filename = String::from("<macro expansion>");
+    filemap_to_tts(parse_sess, parse_sess.codemap().new_filemap(filename, None, text))
 }
 
 impl<'a, 'b> Folder for InvocationCollector<'a, 'b> {
diff --git a/src/libsyntax/ext/tt/macro_parser.rs b/src/libsyntax/ext/tt/macro_parser.rs
index 87c8f3efb6355..089c35c694a78 100644
--- a/src/libsyntax/ext/tt/macro_parser.rs
+++ b/src/libsyntax/ext/tt/macro_parser.rs
@@ -82,7 +82,6 @@ use ast::Ident;
 use syntax_pos::{self, BytePos, mk_sp, Span};
 use codemap::Spanned;
 use errors::FatalError;
-use parse::lexer::*; //resolve bug?
 use parse::{Directory, ParseSess};
 use parse::parser::{PathStyle, Parser};
 use parse::token::{DocComment, MatchNt, SubstNt};
@@ -407,9 +406,9 @@ fn inner_parse_loop(cur_eis: &mut SmallVector<Box<MatcherPos>>,
     Success(())
 }
 
-pub fn parse(sess: &ParseSess, rdr: TtReader, ms: &[TokenTree], directory: Option<Directory>)
+pub fn parse(sess: &ParseSess, tts: Vec<TokenTree>, ms: &[TokenTree], directory: Option<Directory>)
              -> NamedParseResult {
-    let mut parser = Parser::new(sess, Box::new(rdr), directory, true);
+    let mut parser = Parser::new(sess, tts, directory, true);
     let mut cur_eis = SmallVector::one(initial_matcher_pos(ms.to_owned(), parser.span.lo));
     let mut next_eis = Vec::new(); // or proceed normally
 
@@ -481,23 +480,8 @@ fn parse_nt<'a>(p: &mut Parser<'a>, sp: Span, name: &str) -> Nonterminal {
     match name {
         "tt" => {
             p.quote_depth += 1; //but in theory, non-quoted tts might be useful
-            let mut tt = panictry!(p.parse_token_tree());
+            let tt = panictry!(p.parse_token_tree());
             p.quote_depth -= 1;
-            while let TokenTree::Token(sp, token::Interpolated(nt)) = tt {
-                if let token::NtTT(..) = *nt {
-                    match Rc::try_unwrap(nt) {
-                        Ok(token::NtTT(sub_tt)) => tt = sub_tt,
-                        Ok(_) => unreachable!(),
-                        Err(nt_rc) => match *nt_rc {
-                            token::NtTT(ref sub_tt) => tt = sub_tt.clone(),
-                            _ => unreachable!(),
-                        },
-                    }
-                } else {
-                    tt = TokenTree::Token(sp, token::Interpolated(nt.clone()));
-                    break
-                }
-            }
             return token::NtTT(tt);
         }
         _ => {}
@@ -527,7 +511,7 @@ fn parse_nt<'a>(p: &mut Parser<'a>, sp: Span, name: &str) -> Nonterminal {
         "ident" => match p.token {
             token::Ident(sn) => {
                 p.bump();
-                token::NtIdent(Spanned::<Ident>{node: sn, span: p.span})
+                token::NtIdent(Spanned::<Ident>{node: sn, span: p.prev_span})
             }
             _ => {
                 let token_str = pprust::token_to_string(&p.token);
diff --git a/src/libsyntax/ext/tt/macro_rules.rs b/src/libsyntax/ext/tt/macro_rules.rs
index 3abd24b50ba9a..f6a25d4aceed7 100644
--- a/src/libsyntax/ext/tt/macro_rules.rs
+++ b/src/libsyntax/ext/tt/macro_rules.rs
@@ -16,8 +16,8 @@ use ext::expand::{Expansion, ExpansionKind};
 use ext::tt::macro_parser::{Success, Error, Failure};
 use ext::tt::macro_parser::{MatchedSeq, MatchedNonterminal};
 use ext::tt::macro_parser::{parse, parse_failure_msg};
+use ext::tt::transcribe::transcribe;
 use parse::{Directory, ParseSess};
-use parse::lexer::new_tt_reader;
 use parse::parser::Parser;
 use parse::token::{self, NtTT, Token};
 use parse::token::Token::*;
@@ -113,13 +113,12 @@ fn generic_extension<'cx>(cx: &'cx ExtCtxt,
                     _ => cx.span_bug(sp, "malformed macro rhs"),
                 };
                 // rhs has holes ( `$id` and `$(...)` that need filled)
-                let trncbr =
-                    new_tt_reader(&cx.parse_sess.span_diagnostic, Some(named_matches), rhs);
+                let tts = transcribe(&cx.parse_sess.span_diagnostic, Some(named_matches), rhs);
                 let directory = Directory {
                     path: cx.current_expansion.module.directory.clone(),
                     ownership: cx.current_expansion.directory_ownership,
                 };
-                let mut p = Parser::new(cx.parse_sess(), Box::new(trncbr), Some(directory), false);
+                let mut p = Parser::new(cx.parse_sess(), tts, Some(directory), false);
                 p.root_module_name = cx.current_expansion.module.mod_path.last()
                     .map(|id| (*id.name.as_str()).to_owned());
 
@@ -187,10 +186,8 @@ pub fn compile(sess: &ParseSess, def: &ast::MacroDef) -> SyntaxExtension {
         })),
     ];
 
-    // Parse the macro_rules! invocation (`none` is for no interpolations):
-    let arg_reader = new_tt_reader(&sess.span_diagnostic, None, def.body.clone());
-
-    let argument_map = match parse(sess, arg_reader, &argument_gram, None) {
+    // Parse the macro_rules! invocation
+    let argument_map = match parse(sess, def.body.clone(), &argument_gram, None) {
         Success(m) => m,
         Failure(sp, tok) => {
             let s = parse_failure_msg(tok);
diff --git a/src/libsyntax/ext/tt/transcribe.rs b/src/libsyntax/ext/tt/transcribe.rs
index 37e329e5d3b29..38becbe7b1d30 100644
--- a/src/libsyntax/ext/tt/transcribe.rs
+++ b/src/libsyntax/ext/tt/transcribe.rs
@@ -10,10 +10,9 @@
 use self::LockstepIterSize::*;
 
 use ast::Ident;
-use errors::{Handler, DiagnosticBuilder};
+use errors::Handler;
 use ext::tt::macro_parser::{NamedMatch, MatchedSeq, MatchedNonterminal};
-use parse::token::{self, MatchNt, SubstNt, Token, NtIdent};
-use parse::lexer::TokenAndSpan;
+use parse::token::{self, MatchNt, SubstNt, Token, NtIdent, NtTT};
 use syntax_pos::{Span, DUMMY_SP};
 use tokenstream::{self, TokenTree};
 use util::small_vector::SmallVector;
@@ -32,8 +31,8 @@ struct TtFrame {
 }
 
 #[derive(Clone)]
-pub struct TtReader<'a> {
-    pub sp_diag: &'a Handler,
+struct TtReader<'a> {
+    sp_diag: &'a Handler,
     /// the unzipped tree:
     stack: SmallVector<TtFrame>,
     /* for MBE-style macro transcription */
@@ -41,20 +40,15 @@ pub struct TtReader<'a> {
 
     repeat_idx: Vec<usize>,
     repeat_len: Vec<usize>,
-    /* cached: */
-    pub cur_tok: Token,
-    pub cur_span: Span,
-    /// Transform doc comments. Only useful in macro invocations
-    pub fatal_errs: Vec<DiagnosticBuilder<'a>>,
 }
 
 /// This can do Macro-By-Example transcription. On the other hand, if
 /// `src` contains no `TokenTree::Sequence`s, `MatchNt`s or `SubstNt`s, `interp` can
 /// (and should) be None.
-pub fn new_tt_reader(sp_diag: &Handler,
-                     interp: Option<HashMap<Ident, Rc<NamedMatch>>>,
-                     src: Vec<tokenstream::TokenTree>)
-                     -> TtReader {
+pub fn transcribe(sp_diag: &Handler,
+                  interp: Option<HashMap<Ident, Rc<NamedMatch>>>,
+                  src: Vec<tokenstream::TokenTree>)
+                  -> Vec<TokenTree> {
     let mut r = TtReader {
         sp_diag: sp_diag,
         stack: SmallVector::one(TtFrame {
@@ -73,13 +67,15 @@ pub fn new_tt_reader(sp_diag: &Handler,
         },
         repeat_idx: Vec::new(),
         repeat_len: Vec::new(),
-        /* dummy values, never read: */
-        cur_tok: token::Eof,
-        cur_span: DUMMY_SP,
-        fatal_errs: Vec::new(),
     };
-    tt_next_token(&mut r); /* get cur_tok and cur_span set up */
-    r
+
+    let mut tts = Vec::new();
+    let mut prev_span = DUMMY_SP;
+    while let Some(tt) = tt_next_token(&mut r, prev_span) {
+        prev_span = tt.span();
+        tts.push(tt);
+    }
+    tts
 }
 
 fn lookup_cur_matched_by_matched(r: &TtReader, start: Rc<NamedMatch>) -> Rc<NamedMatch> {
@@ -153,38 +149,24 @@ fn lockstep_iter_size(t: &TokenTree, r: &TtReader) -> LockstepIterSize {
 
 /// Return the next token from the TtReader.
 /// EFFECT: advances the reader's token field
-pub fn tt_next_token(r: &mut TtReader) -> TokenAndSpan {
-    // FIXME(pcwalton): Bad copy?
-    let ret_val = TokenAndSpan {
-        tok: r.cur_tok.clone(),
-        sp: r.cur_span.clone(),
-    };
+fn tt_next_token(r: &mut TtReader, prev_span: Span) -> Option<TokenTree> {
     loop {
-        let should_pop = match r.stack.last() {
-            None => {
-                assert_eq!(ret_val.tok, token::Eof);
-                return ret_val;
-            }
-            Some(frame) => {
-                if frame.idx < frame.forest.len() {
-                    break;
-                }
-                !frame.dotdotdoted ||
-                    *r.repeat_idx.last().unwrap() == *r.repeat_len.last().unwrap() - 1
+        let should_pop = if let Some(frame) = r.stack.last() {
+            if frame.idx < frame.forest.len() {
+                break;
             }
+            !frame.dotdotdoted || *r.repeat_idx.last().unwrap() == *r.repeat_len.last().unwrap() - 1
+        } else {
+            return None;
         };
 
         /* done with this set; pop or repeat? */
         if should_pop {
             let prev = r.stack.pop().unwrap();
-            match r.stack.last_mut() {
-                None => {
-                    r.cur_tok = token::Eof;
-                    return ret_val;
-                }
-                Some(frame) => {
-                    frame.idx += 1;
-                }
+            if let Some(frame) = r.stack.last_mut() {
+                frame.idx += 1;
+            } else {
+                return None;
             }
             if prev.dotdotdoted {
                 r.repeat_idx.pop();
@@ -194,8 +176,7 @@ pub fn tt_next_token(r: &mut TtReader) -> TokenAndSpan {
             *r.repeat_idx.last_mut().unwrap() += 1;
             r.stack.last_mut().unwrap().idx = 0;
             if let Some(tk) = r.stack.last().unwrap().sep.clone() {
-                r.cur_tok = tk; // repeat same span, I guess
-                return ret_val;
+                return Some(TokenTree::Token(prev_span, tk)); // repeat same span, I guess
             }
         }
     }
@@ -231,7 +212,7 @@ pub fn tt_next_token(r: &mut TtReader) -> TokenAndSpan {
                             }
 
                             r.stack.last_mut().unwrap().idx += 1;
-                            return tt_next_token(r);
+                            return tt_next_token(r, prev_span);
                         }
                         r.repeat_len.push(len);
                         r.repeat_idx.push(0);
@@ -249,9 +230,7 @@ pub fn tt_next_token(r: &mut TtReader) -> TokenAndSpan {
                 r.stack.last_mut().unwrap().idx += 1;
                 match lookup_cur_matched(r, ident) {
                     None => {
-                        r.cur_span = sp;
-                        r.cur_tok = SubstNt(ident);
-                        return ret_val;
+                        return Some(TokenTree::Token(sp, SubstNt(ident)));
                         // this can't be 0 length, just like TokenTree::Delimited
                     }
                     Some(cur_matched) => if let MatchedNonterminal(ref nt) = *cur_matched {
@@ -260,15 +239,12 @@ pub fn tt_next_token(r: &mut TtReader) -> TokenAndSpan {
                             // (a) idents can be in lots of places, so it'd be a pain
                             // (b) we actually can, since it's a token.
                             NtIdent(ref sn) => {
-                                r.cur_span = sn.span;
-                                r.cur_tok = token::Ident(sn.node);
-                                return ret_val;
+                                return Some(TokenTree::Token(sn.span, token::Ident(sn.node)));
                             }
+                            NtTT(ref tt) => return Some(tt.clone()),
                             _ => {
-                                // FIXME(pcwalton): Bad copy.
-                                r.cur_span = sp;
-                                r.cur_tok = token::Interpolated(nt.clone());
-                                return ret_val;
+                                // FIXME(pcwalton): Bad copy
+                                return Some(TokenTree::Token(sp, token::Interpolated(nt.clone())));
                             }
                         }
                     } else {
@@ -289,11 +265,9 @@ pub fn tt_next_token(r: &mut TtReader) -> TokenAndSpan {
                 });
                 // if this could be 0-length, we'd need to potentially recur here
             }
-            TokenTree::Token(sp, tok) => {
-                r.cur_span = sp;
-                r.cur_tok = tok;
+            tt @ TokenTree::Token(..) => {
                 r.stack.last_mut().unwrap().idx += 1;
-                return ret_val;
+                return Some(tt);
             }
         }
     }
diff --git a/src/libsyntax/feature_gate.rs b/src/libsyntax/feature_gate.rs
index 924f51fd95251..c25020caf857e 100644
--- a/src/libsyntax/feature_gate.rs
+++ b/src/libsyntax/feature_gate.rs
@@ -30,7 +30,7 @@ use ast::{self, NodeId, PatKind};
 use attr;
 use codemap::{CodeMap, Spanned};
 use syntax_pos::Span;
-use errors::{DiagnosticBuilder, Handler};
+use errors::{DiagnosticBuilder, Handler, FatalError};
 use visit::{self, FnKind, Visitor};
 use parse::ParseSess;
 use symbol::Symbol;
@@ -319,6 +319,9 @@ declare_features! (
     // The `unadjusted` ABI. Perma unstable.
     (active, abi_unadjusted, "1.16.0", None),
 
+    // Macros 1.1
+    (active, proc_macro, "1.16.0", Some(35900)),
+
     // Allows attributes on struct literal fields.
     (active, struct_field_attributes, "1.16.0", Some(38814)),
 
@@ -375,8 +378,6 @@ declare_features! (
     // Allows `..` in tuple (struct) patterns
     (accepted, dotdot_in_tuple_patterns, "1.14.0", Some(33627)),
     (accepted, item_like_imports, "1.14.0", Some(35120)),
-    // Macros 1.1
-    (accepted, proc_macro, "1.15.0", Some(35900)),
 );
 // (changing above list without updating src/doc/reference.md makes @cmr sad)
 
@@ -444,6 +445,10 @@ pub fn deprecated_attributes() -> Vec<&'static (&'static str, AttributeType, Att
     BUILTIN_ATTRIBUTES.iter().filter(|a| a.2.is_deprecated()).collect()
 }
 
+pub fn is_builtin_attr(attr: &ast::Attribute) -> bool {
+    BUILTIN_ATTRIBUTES.iter().any(|&(builtin_name, _, _)| attr.check_name(builtin_name))
+}
+
 // Attributes that have a special meaning to rustc or rustdoc
 pub const BUILTIN_ATTRIBUTES: &'static [(&'static str, AttributeType, AttributeGate)] = &[
     // Normal attributes
@@ -737,6 +742,16 @@ pub const BUILTIN_ATTRIBUTES: &'static [(&'static str, AttributeType, AttributeG
                                               is currently unstable",
                                              cfg_fn!(windows_subsystem))),
 
+    ("proc_macro_attribute", Normal, Gated(Stability::Unstable,
+                                           "proc_macro",
+                                           "attribute proc macros are currently unstable",
+                                           cfg_fn!(proc_macro))),
+
+    ("rustc_derive_registrar", Normal, Gated(Stability::Unstable,
+                                             "rustc_derive_registrar",
+                                             "used internally by rustc",
+                                             cfg_fn!(rustc_attrs))),
+
     // Crate level attributes
     ("crate_name", CrateLevel, Ungated),
     ("crate_type", CrateLevel, Ungated),
@@ -879,9 +894,10 @@ fn find_lang_feature_issue(feature: &str) -> Option<u32> {
         issue
     } else {
         // search in Accepted or Removed features
-        ACCEPTED_FEATURES.iter().chain(REMOVED_FEATURES.iter())
-            .find(|t| t.0 == feature)
-            .unwrap().2
+        match ACCEPTED_FEATURES.iter().chain(REMOVED_FEATURES).find(|t| t.0 == feature) {
+            Some(&(_, _, issue)) => issue,
+            None => panic!("Feature `{}` is not declared anywhere", feature),
+        }
     }
 }
 
@@ -1382,6 +1398,8 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
 pub fn get_features(span_handler: &Handler, krate_attrs: &[ast::Attribute]) -> Features {
     let mut features = Features::new();
 
+    let mut feature_checker = MutexFeatureChecker::default();
+
     for attr in krate_attrs {
         if !attr.check_name("feature") {
             continue
@@ -1405,6 +1423,7 @@ pub fn get_features(span_handler: &Handler, krate_attrs: &[ast::Attribute]) -> F
                     if let Some(&(_, _, _, setter)) = ACTIVE_FEATURES.iter()
                         .find(|& &(n, _, _, _)| name == n) {
                         *(setter(&mut features)) = true;
+                        feature_checker.collect(&features, mi.span);
                     }
                     else if let Some(&(_, _, _)) = REMOVED_FEATURES.iter()
                         .find(|& &(n, _, _)| name == n) {
@@ -1421,9 +1440,45 @@ pub fn get_features(span_handler: &Handler, krate_attrs: &[ast::Attribute]) -> F
         }
     }
 
+    feature_checker.check(span_handler);
+
     features
 }
 
+// A collector for mutually-exclusive features and their flag spans
+#[derive(Default)]
+struct MutexFeatureChecker {
+    proc_macro: Option<Span>,
+    custom_attribute: Option<Span>,
+}
+
+impl MutexFeatureChecker {
+    // If this method turns out to be a hotspot due to branching,
+    // the branching can be eliminated by modifying `setter!()` to set these spans
+    // only for the features that need to be checked for mutual exclusion.
+    fn collect(&mut self, features: &Features, span: Span) {
+        if features.proc_macro {
+            // If self.proc_macro is None, set to Some(span)
+            self.proc_macro = self.proc_macro.or(Some(span));
+        }
+
+        if features.custom_attribute {
+            self.custom_attribute = self.custom_attribute.or(Some(span));
+        }
+    }
+
+    fn check(self, handler: &Handler) {
+        if let (Some(pm_span), Some(ca_span)) = (self.proc_macro, self.custom_attribute) {
+            handler.struct_span_err(pm_span, "Cannot use `#![feature(proc_macro)]` and \
+                                              `#![feature(custom_attribute)] at the same time")
+                .span_note(ca_span, "`#![feature(custom_attribute)]` declared here")
+                .emit();
+
+            panic!(FatalError);
+        }
+    }
+}
+
 pub fn check_crate(krate: &ast::Crate,
                    sess: &ParseSess,
                    features: &Features,
diff --git a/src/libsyntax/parse/lexer/comments.rs b/src/libsyntax/parse/lexer/comments.rs
index ba83a55ea7937..c97b8ddf91972 100644
--- a/src/libsyntax/parse/lexer/comments.rs
+++ b/src/libsyntax/parse/lexer/comments.rs
@@ -13,11 +13,8 @@ pub use self::CommentStyle::*;
 use ast;
 use codemap::CodeMap;
 use syntax_pos::{BytePos, CharPos, Pos};
-use errors;
-use parse::lexer::is_block_doc_comment;
-use parse::lexer::{StringReader, TokenAndSpan};
-use parse::lexer::{is_pattern_whitespace, Reader};
-use parse::lexer;
+use parse::lexer::{is_block_doc_comment, is_pattern_whitespace};
+use parse::lexer::{self, ParseSess, StringReader, TokenAndSpan};
 use print::pprust;
 use str::char_at;
 
@@ -346,16 +343,14 @@ pub struct Literal {
 
 // it appears this function is called only from pprust... that's
 // probably not a good thing.
-pub fn gather_comments_and_literals(span_diagnostic: &errors::Handler,
-                                    path: String,
-                                    srdr: &mut Read)
+pub fn gather_comments_and_literals(sess: &ParseSess, path: String, srdr: &mut Read)
                                     -> (Vec<Comment>, Vec<Literal>) {
     let mut src = Vec::new();
     srdr.read_to_end(&mut src).unwrap();
     let src = String::from_utf8(src).unwrap();
     let cm = CodeMap::new();
     let filemap = cm.new_filemap(path, None, src);
-    let mut rdr = lexer::StringReader::new_raw(span_diagnostic, filemap);
+    let mut rdr = lexer::StringReader::new_raw(sess, filemap);
 
     let mut comments: Vec<Comment> = Vec::new();
     let mut literals: Vec<Literal> = Vec::new();
diff --git a/src/libsyntax/parse/lexer/mod.rs b/src/libsyntax/parse/lexer/mod.rs
index 818742e4492f2..6bc15115b09d3 100644
--- a/src/libsyntax/parse/lexer/mod.rs
+++ b/src/libsyntax/parse/lexer/mod.rs
@@ -11,9 +11,8 @@
 use ast::{self, Ident};
 use syntax_pos::{self, BytePos, CharPos, Pos, Span};
 use codemap::CodeMap;
-use errors::{FatalError, Handler, DiagnosticBuilder};
-use ext::tt::transcribe::tt_next_token;
-use parse::token;
+use errors::{FatalError, DiagnosticBuilder};
+use parse::{token, ParseSess};
 use str::char_at;
 use symbol::{Symbol, keywords};
 use std_unicode::property::Pattern_White_Space;
@@ -23,52 +22,10 @@ use std::char;
 use std::mem::replace;
 use std::rc::Rc;
 
-pub use ext::tt::transcribe::{TtReader, new_tt_reader};
-
 pub mod comments;
+mod tokentrees;
 mod unicode_chars;
 
-pub trait Reader {
-    fn is_eof(&self) -> bool;
-    fn try_next_token(&mut self) -> Result<TokenAndSpan, ()>;
-    fn next_token(&mut self) -> TokenAndSpan where Self: Sized {
-        let res = self.try_next_token();
-        self.unwrap_or_abort(res)
-    }
-    /// Report a fatal error with the current span.
-    fn fatal(&self, &str) -> FatalError;
-    /// Report a non-fatal error with the current span.
-    fn err(&self, &str);
-    fn emit_fatal_errors(&mut self);
-    fn unwrap_or_abort(&mut self, res: Result<TokenAndSpan, ()>) -> TokenAndSpan {
-        match res {
-            Ok(tok) => tok,
-            Err(_) => {
-                self.emit_fatal_errors();
-                panic!(FatalError);
-            }
-        }
-    }
-    fn peek(&self) -> TokenAndSpan;
-    /// Get a token the parser cares about.
-    fn try_real_token(&mut self) -> Result<TokenAndSpan, ()> {
-        let mut t = self.try_next_token()?;
-        loop {
-            match t.tok {
-                token::Whitespace | token::Comment | token::Shebang(_) => {
-                    t = self.try_next_token()?;
-                }
-                _ => break,
-            }
-        }
-        Ok(t)
-    }
-    fn real_token(&mut self) -> TokenAndSpan {
-        let res = self.try_real_token();
-        self.unwrap_or_abort(res)
-    }
-}
-
 #[derive(Clone, PartialEq, Eq, Debug)]
 pub struct TokenAndSpan {
     pub tok: token::Token,
@@ -82,7 +39,7 @@ impl Default for TokenAndSpan {
 }
 
 pub struct StringReader<'a> {
-    pub span_diagnostic: &'a Handler,
+    pub sess: &'a ParseSess,
     /// The absolute offset within the codemap of the next character to read
     pub next_pos: BytePos,
     /// The absolute offset within the codemap of the current character
@@ -105,9 +62,44 @@ pub struct StringReader<'a> {
     // cache a direct reference to the source text, so that we don't have to
     // retrieve it via `self.filemap.src.as_ref().unwrap()` all the time.
     source_text: Rc<String>,
+    /// Stack of open delimiters and their spans. Used for error message.
+    token: token::Token,
+    span: Span,
+    open_braces: Vec<(token::DelimToken, Span)>,
 }
 
-impl<'a> Reader for StringReader<'a> {
+impl<'a> StringReader<'a> {
+    fn next_token(&mut self) -> TokenAndSpan where Self: Sized {
+        let res = self.try_next_token();
+        self.unwrap_or_abort(res)
+    }
+    fn unwrap_or_abort(&mut self, res: Result<TokenAndSpan, ()>) -> TokenAndSpan {
+        match res {
+            Ok(tok) => tok,
+            Err(_) => {
+                self.emit_fatal_errors();
+                panic!(FatalError);
+            }
+        }
+    }
+    fn try_real_token(&mut self) -> Result<TokenAndSpan, ()> {
+        let mut t = self.try_next_token()?;
+        loop {
+            match t.tok {
+                token::Whitespace | token::Comment | token::Shebang(_) => {
+                    t = self.try_next_token()?;
+                }
+                _ => break,
+            }
+        }
+        self.token = t.tok.clone();
+        self.span = t.sp;
+        Ok(t)
+    }
+    pub fn real_token(&mut self) -> TokenAndSpan {
+        let res = self.try_real_token();
+        self.unwrap_or_abort(res)
+    }
     fn is_eof(&self) -> bool {
         if self.ch.is_none() {
             return true;
@@ -119,7 +111,7 @@ impl<'a> Reader for StringReader<'a> {
         }
     }
     /// Return the next token. EFFECT: advances the string_reader.
-    fn try_next_token(&mut self) -> Result<TokenAndSpan, ()> {
+    pub fn try_next_token(&mut self) -> Result<TokenAndSpan, ()> {
         assert!(self.fatal_errs.is_empty());
         let ret_val = TokenAndSpan {
             tok: replace(&mut self.peek_tok, token::Underscore),
@@ -131,16 +123,13 @@ impl<'a> Reader for StringReader<'a> {
     fn fatal(&self, m: &str) -> FatalError {
         self.fatal_span(self.peek_span, m)
     }
-    fn err(&self, m: &str) {
-        self.err_span(self.peek_span, m)
-    }
-    fn emit_fatal_errors(&mut self) {
+    pub fn emit_fatal_errors(&mut self) {
         for err in &mut self.fatal_errs {
             err.emit();
         }
         self.fatal_errs.clear();
     }
-    fn peek(&self) -> TokenAndSpan {
+    pub fn peek(&self) -> TokenAndSpan {
         // FIXME(pcwalton): Bad copy!
         TokenAndSpan {
             tok: self.peek_tok.clone(),
@@ -149,59 +138,24 @@ impl<'a> Reader for StringReader<'a> {
     }
 }
 
-impl<'a> Reader for TtReader<'a> {
-    fn is_eof(&self) -> bool {
-        self.peek().tok == token::Eof
-    }
-    fn try_next_token(&mut self) -> Result<TokenAndSpan, ()> {
-        assert!(self.fatal_errs.is_empty());
-        let r = tt_next_token(self);
-        debug!("TtReader: r={:?}", r);
-        Ok(r)
-    }
-    fn fatal(&self, m: &str) -> FatalError {
-        self.sp_diag.span_fatal(self.cur_span, m)
-    }
-    fn err(&self, m: &str) {
-        self.sp_diag.span_err(self.cur_span, m);
-    }
-    fn emit_fatal_errors(&mut self) {
-        for err in &mut self.fatal_errs {
-            err.emit();
-        }
-        self.fatal_errs.clear();
-    }
-    fn peek(&self) -> TokenAndSpan {
-        TokenAndSpan {
-            tok: self.cur_tok.clone(),
-            sp: self.cur_span,
-        }
-    }
-}
-
 impl<'a> StringReader<'a> {
     /// For comments.rs, which hackily pokes into next_pos and ch
-    pub fn new_raw<'b>(span_diagnostic: &'b Handler,
-                       filemap: Rc<syntax_pos::FileMap>)
-                       -> StringReader<'b> {
-        let mut sr = StringReader::new_raw_internal(span_diagnostic, filemap);
+    pub fn new_raw<'b>(sess: &'a ParseSess, filemap: Rc<syntax_pos::FileMap>) -> Self {
+        let mut sr = StringReader::new_raw_internal(sess, filemap);
         sr.bump();
         sr
     }
 
-    fn new_raw_internal<'b>(span_diagnostic: &'b Handler,
-                            filemap: Rc<syntax_pos::FileMap>)
-                            -> StringReader<'b> {
+    fn new_raw_internal(sess: &'a ParseSess, filemap: Rc<syntax_pos::FileMap>) -> Self {
         if filemap.src.is_none() {
-            span_diagnostic.bug(&format!("Cannot lex filemap \
-                                          without source: {}",
-                                         filemap.name)[..]);
+            sess.span_diagnostic.bug(&format!("Cannot lex filemap without source: {}",
+                                              filemap.name));
         }
 
         let source_text = (*filemap.src.as_ref().unwrap()).clone();
 
         StringReader {
-            span_diagnostic: span_diagnostic,
+            sess: sess,
             next_pos: filemap.start_pos,
             pos: filemap.start_pos,
             col: CharPos(0),
@@ -214,13 +168,14 @@ impl<'a> StringReader<'a> {
             peek_span: syntax_pos::DUMMY_SP,
             source_text: source_text,
             fatal_errs: Vec::new(),
+            token: token::Eof,
+            span: syntax_pos::DUMMY_SP,
+            open_braces: Vec::new(),
         }
     }
 
-    pub fn new<'b>(span_diagnostic: &'b Handler,
-                   filemap: Rc<syntax_pos::FileMap>)
-                   -> StringReader<'b> {
-        let mut sr = StringReader::new_raw(span_diagnostic, filemap);
+    pub fn new(sess: &'a ParseSess, filemap: Rc<syntax_pos::FileMap>) -> Self {
+        let mut sr = StringReader::new_raw(sess, filemap);
         if let Err(_) = sr.advance_token() {
             sr.emit_fatal_errors();
             panic!(FatalError);
@@ -234,12 +189,12 @@ impl<'a> StringReader<'a> {
 
     /// Report a fatal lexical error with a given span.
     pub fn fatal_span(&self, sp: Span, m: &str) -> FatalError {
-        self.span_diagnostic.span_fatal(sp, m)
+        self.sess.span_diagnostic.span_fatal(sp, m)
     }
 
     /// Report a lexical error with a given span.
     pub fn err_span(&self, sp: Span, m: &str) {
-        self.span_diagnostic.span_err(sp, m)
+        self.sess.span_diagnostic.span_err(sp, m)
     }
 
 
@@ -274,7 +229,7 @@ impl<'a> StringReader<'a> {
         for c in c.escape_default() {
             m.push(c)
         }
-        self.span_diagnostic.struct_span_fatal(syntax_pos::mk_sp(from_pos, to_pos), &m[..])
+        self.sess.span_diagnostic.struct_span_fatal(syntax_pos::mk_sp(from_pos, to_pos), &m[..])
     }
 
     /// Report a lexical error spanning [`from_pos`, `to_pos`), appending an
@@ -298,7 +253,7 @@ impl<'a> StringReader<'a> {
         for c in c.escape_default() {
             m.push(c)
         }
-        self.span_diagnostic.struct_span_err(syntax_pos::mk_sp(from_pos, to_pos), &m[..])
+        self.sess.span_diagnostic.struct_span_err(syntax_pos::mk_sp(from_pos, to_pos), &m[..])
     }
 
     /// Report a lexical error spanning [`from_pos`, `to_pos`), appending the
@@ -503,9 +458,8 @@ impl<'a> StringReader<'a> {
     fn scan_comment(&mut self) -> Option<TokenAndSpan> {
         if let Some(c) = self.ch {
             if c.is_whitespace() {
-                self.span_diagnostic.span_err(syntax_pos::mk_sp(self.pos, self.pos),
-                                              "called consume_any_line_comment, but there \
-                                               was whitespace");
+                let msg = "called consume_any_line_comment, but there was whitespace";
+                self.sess.span_diagnostic.span_err(syntax_pos::mk_sp(self.pos, self.pos), msg);
             }
         }
 
@@ -875,7 +829,7 @@ impl<'a> StringReader<'a> {
                                     self.scan_unicode_escape(delim) && !ascii_only
                                 } else {
                                     let span = syntax_pos::mk_sp(start, self.pos);
-                                    self.span_diagnostic
+                                    self.sess.span_diagnostic
                                         .struct_span_err(span, "incorrect unicode escape sequence")
                                         .span_help(span,
                                                    "format of unicode escape sequences is \
@@ -1701,35 +1655,41 @@ fn ident_continue(c: Option<char>) -> bool {
 mod tests {
     use super::*;
 
-    use ast::Ident;
+    use ast::{Ident, CrateConfig};
     use symbol::Symbol;
     use syntax_pos::{BytePos, Span, NO_EXPANSION};
     use codemap::CodeMap;
     use errors;
+    use feature_gate::UnstableFeatures;
     use parse::token;
+    use std::cell::RefCell;
     use std::io;
     use std::rc::Rc;
 
-    fn mk_sh(cm: Rc<CodeMap>) -> errors::Handler {
-        // FIXME (#22405): Replace `Box::new` with `box` here when/if possible.
-        let emitter = errors::emitter::EmitterWriter::new(Box::new(io::sink()),
-                                                Some(cm));
-        errors::Handler::with_emitter(true, false, Box::new(emitter))
+    fn mk_sess(cm: Rc<CodeMap>) -> ParseSess {
+        let emitter = errors::emitter::EmitterWriter::new(Box::new(io::sink()), Some(cm.clone()));
+        ParseSess {
+            span_diagnostic: errors::Handler::with_emitter(true, false, Box::new(emitter)),
+            unstable_features: UnstableFeatures::from_environment(),
+            config: CrateConfig::new(),
+            included_mod_stack: RefCell::new(Vec::new()),
+            code_map: cm,
+        }
     }
 
     // open a string reader for the given string
     fn setup<'a>(cm: &CodeMap,
-                 span_handler: &'a errors::Handler,
+                 sess: &'a ParseSess,
                  teststr: String)
                  -> StringReader<'a> {
         let fm = cm.new_filemap("zebra.rs".to_string(), None, teststr);
-        StringReader::new(span_handler, fm)
+        StringReader::new(sess, fm)
     }
 
     #[test]
     fn t1() {
         let cm = Rc::new(CodeMap::new());
-        let sh = mk_sh(cm.clone());
+        let sh = mk_sess(cm.clone());
         let mut string_reader = setup(&cm,
                                       &sh,
                                       "/* my source file */ fn main() { println!(\"zebra\"); }\n"
@@ -1781,7 +1741,7 @@ mod tests {
     #[test]
     fn doublecolonparsing() {
         let cm = Rc::new(CodeMap::new());
-        let sh = mk_sh(cm.clone());
+        let sh = mk_sess(cm.clone());
         check_tokenization(setup(&cm, &sh, "a b".to_string()),
                            vec![mk_ident("a"), token::Whitespace, mk_ident("b")]);
     }
@@ -1789,7 +1749,7 @@ mod tests {
     #[test]
     fn dcparsing_2() {
         let cm = Rc::new(CodeMap::new());
-        let sh = mk_sh(cm.clone());
+        let sh = mk_sess(cm.clone());
         check_tokenization(setup(&cm, &sh, "a::b".to_string()),
                            vec![mk_ident("a"), token::ModSep, mk_ident("b")]);
     }
@@ -1797,7 +1757,7 @@ mod tests {
     #[test]
     fn dcparsing_3() {
         let cm = Rc::new(CodeMap::new());
-        let sh = mk_sh(cm.clone());
+        let sh = mk_sess(cm.clone());
         check_tokenization(setup(&cm, &sh, "a ::b".to_string()),
                            vec![mk_ident("a"), token::Whitespace, token::ModSep, mk_ident("b")]);
     }
@@ -1805,7 +1765,7 @@ mod tests {
     #[test]
     fn dcparsing_4() {
         let cm = Rc::new(CodeMap::new());
-        let sh = mk_sh(cm.clone());
+        let sh = mk_sess(cm.clone());
         check_tokenization(setup(&cm, &sh, "a:: b".to_string()),
                            vec![mk_ident("a"), token::ModSep, token::Whitespace, mk_ident("b")]);
     }
@@ -1813,7 +1773,7 @@ mod tests {
     #[test]
     fn character_a() {
         let cm = Rc::new(CodeMap::new());
-        let sh = mk_sh(cm.clone());
+        let sh = mk_sess(cm.clone());
         assert_eq!(setup(&cm, &sh, "'a'".to_string()).next_token().tok,
                    token::Literal(token::Char(Symbol::intern("a")), None));
     }
@@ -1821,7 +1781,7 @@ mod tests {
     #[test]
     fn character_space() {
         let cm = Rc::new(CodeMap::new());
-        let sh = mk_sh(cm.clone());
+        let sh = mk_sess(cm.clone());
         assert_eq!(setup(&cm, &sh, "' '".to_string()).next_token().tok,
                    token::Literal(token::Char(Symbol::intern(" ")), None));
     }
@@ -1829,7 +1789,7 @@ mod tests {
     #[test]
     fn character_escaped() {
         let cm = Rc::new(CodeMap::new());
-        let sh = mk_sh(cm.clone());
+        let sh = mk_sess(cm.clone());
         assert_eq!(setup(&cm, &sh, "'\\n'".to_string()).next_token().tok,
                    token::Literal(token::Char(Symbol::intern("\\n")), None));
     }
@@ -1837,7 +1797,7 @@ mod tests {
     #[test]
     fn lifetime_name() {
         let cm = Rc::new(CodeMap::new());
-        let sh = mk_sh(cm.clone());
+        let sh = mk_sess(cm.clone());
         assert_eq!(setup(&cm, &sh, "'abc".to_string()).next_token().tok,
                    token::Lifetime(Ident::from_str("'abc")));
     }
@@ -1845,7 +1805,7 @@ mod tests {
     #[test]
     fn raw_string() {
         let cm = Rc::new(CodeMap::new());
-        let sh = mk_sh(cm.clone());
+        let sh = mk_sess(cm.clone());
         assert_eq!(setup(&cm, &sh, "r###\"\"#a\\b\x00c\"\"###".to_string())
                        .next_token()
                        .tok,
@@ -1855,7 +1815,7 @@ mod tests {
     #[test]
     fn literal_suffixes() {
         let cm = Rc::new(CodeMap::new());
-        let sh = mk_sh(cm.clone());
+        let sh = mk_sess(cm.clone());
         macro_rules! test {
             ($input: expr, $tok_type: ident, $tok_contents: expr) => {{
                 assert_eq!(setup(&cm, &sh, format!("{}suffix", $input)).next_token().tok,
@@ -1899,7 +1859,7 @@ mod tests {
     #[test]
     fn nested_block_comments() {
         let cm = Rc::new(CodeMap::new());
-        let sh = mk_sh(cm.clone());
+        let sh = mk_sess(cm.clone());
         let mut lexer = setup(&cm, &sh, "/* /* */ */'a'".to_string());
         match lexer.next_token().tok {
             token::Comment => {}
@@ -1912,7 +1872,7 @@ mod tests {
     #[test]
     fn crlf_comments() {
         let cm = Rc::new(CodeMap::new());
-        let sh = mk_sh(cm.clone());
+        let sh = mk_sess(cm.clone());
         let mut lexer = setup(&cm, &sh, "// test\r\n/// test\r\n".to_string());
         let comment = lexer.next_token();
         assert_eq!(comment.tok, token::Comment);
diff --git a/src/libsyntax/parse/lexer/tokentrees.rs b/src/libsyntax/parse/lexer/tokentrees.rs
new file mode 100644
index 0000000000000..7b6f00e0e8265
--- /dev/null
+++ b/src/libsyntax/parse/lexer/tokentrees.rs
@@ -0,0 +1,138 @@
+// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+use print::pprust::token_to_string;
+use parse::lexer::StringReader;
+use parse::{token, PResult};
+use syntax_pos::Span;
+use tokenstream::{Delimited, TokenTree};
+
+use std::rc::Rc;
+
+impl<'a> StringReader<'a> {
+    // Parse a stream of tokens into a list of `TokenTree`s, up to an `Eof`.
+    pub fn parse_all_token_trees(&mut self) -> PResult<'a, Vec<TokenTree>> {
+        let mut tts = Vec::new();
+        while self.token != token::Eof {
+            tts.push(self.parse_token_tree()?);
+        }
+        Ok(tts)
+    }
+
+    // Parse a stream of tokens into a list of `TokenTree`s, up to a `CloseDelim`.
+    fn parse_token_trees_until_close_delim(&mut self) -> Vec<TokenTree> {
+        let mut tts = vec![];
+        loop {
+            if let token::CloseDelim(..) = self.token {
+                return tts;
+            }
+            match self.parse_token_tree() {
+                Ok(tt) => tts.push(tt),
+                Err(mut e) => {
+                    e.emit();
+                    return tts;
+                }
+            }
+        }
+    }
+
+    fn parse_token_tree(&mut self) -> PResult<'a, TokenTree> {
+        match self.token {
+            token::Eof => {
+                let msg = "this file contains an un-closed delimiter";
+                let mut err = self.sess.span_diagnostic.struct_span_err(self.span, msg);
+                for &(_, sp) in &self.open_braces {
+                    err.span_help(sp, "did you mean to close this delimiter?");
+                }
+                Err(err)
+            },
+            token::OpenDelim(delim) => {
+                // The span for beginning of the delimited section
+                let pre_span = self.span;
+
+                // Parse the open delimiter.
+                self.open_braces.push((delim, self.span));
+                let open_span = self.span;
+                self.real_token();
+
+                // Parse the token trees within the delimiters.
+                // We stop at any delimiter so we can try to recover if the user
+                // uses an incorrect delimiter.
+                let tts = self.parse_token_trees_until_close_delim();
+
+                let close_span = self.span;
+                // Expand to cover the entire delimited token tree
+                let span = Span { hi: close_span.hi, ..pre_span };
+
+                match self.token {
+                    // Correct delimiter.
+                    token::CloseDelim(d) if d == delim => {
+                        self.open_braces.pop().unwrap();
+
+                        // Parse the close delimiter.
+                        self.real_token();
+                    }
+                    // Incorrect delimiter.
+                    token::CloseDelim(other) => {
+                        let token_str = token_to_string(&self.token);
+                        let msg = format!("incorrect close delimiter: `{}`", token_str);
+                        let mut err = self.sess.span_diagnostic.struct_span_err(self.span, &msg);
+                        // This is a conservative error: only report the last unclosed delimiter.
+                        // The previous unclosed delimiters could actually be closed! The parser
+                        // just hasn't gotten to them yet.
+                        if let Some(&(_, sp)) = self.open_braces.last() {
+                            err.span_note(sp, "unclosed delimiter");
+                        };
+                        err.emit();
+
+                        self.open_braces.pop().unwrap();
+
+                        // If the incorrect delimiter matches an earlier opening
+                        // delimiter, then don't consume it (it can be used to
+                        // close the earlier one). Otherwise, consume it.
+                        // E.g., we try to recover from:
+                        // fn foo() {
+                        //     bar(baz(
+                        // }  // Incorrect delimiter but matches the earlier `{`
+                        if !self.open_braces.iter().any(|&(b, _)| b == other) {
+                            self.real_token();
+                        }
+                    }
+                    token::Eof => {
+                        // Silently recover, the EOF token will be seen again
+                        // and an error emitted then. Thus we don't pop from
+                        // self.open_braces here.
+                    },
+                    _ => {}
+                }
+
+                Ok(TokenTree::Delimited(span, Rc::new(Delimited {
+                    delim: delim,
+                    open_span: open_span,
+                    tts: tts,
+                    close_span: close_span,
+                })))
+            },
+            token::CloseDelim(_) => {
+                // An unexpected closing delimiter (i.e., there is no
+                // matching opening delimiter).
+                let token_str = token_to_string(&self.token);
+                let msg = format!("unexpected close delimiter: `{}`", token_str);
+                let err = self.sess.span_diagnostic.struct_span_err(self.span, &msg);
+                Err(err)
+            },
+            _ => {
+                let tt = TokenTree::Token(self.span, self.token.clone());
+                self.real_token();
+                Ok(tt)
+            }
+        }
+    }
+}
diff --git a/src/libsyntax/parse/lexer/unicode_chars.rs b/src/libsyntax/parse/lexer/unicode_chars.rs
index 1e08b20b7e1f4..6da3e5de75cdc 100644
--- a/src/libsyntax/parse/lexer/unicode_chars.rs
+++ b/src/libsyntax/parse/lexer/unicode_chars.rs
@@ -243,10 +243,8 @@ pub fn check_for_substitution<'a>(reader: &StringReader<'a>,
                 err.span_help(span, &msg);
             },
             None => {
-                reader
-                .span_diagnostic
-                .span_bug_no_panic(span,
-                                   &format!("substitution character not found for '{}'", ch));
+                let msg = format!("substitution character not found for '{}'", ch);
+                reader.sess.span_diagnostic.span_bug_no_panic(span, &msg);
             }
         }
     });
diff --git a/src/libsyntax/parse/mod.rs b/src/libsyntax/parse/mod.rs
index 1a1950dc45c61..08f5df4515ba6 100644
--- a/src/libsyntax/parse/mod.rs
+++ b/src/libsyntax/parse/mod.rs
@@ -45,7 +45,7 @@ pub mod obsolete;
 
 /// Info about a parsing session.
 pub struct ParseSess {
-    pub span_diagnostic: Handler, // better be the same as the one in the reader!
+    pub span_diagnostic: Handler,
     pub unstable_features: UnstableFeatures,
     pub config: CrateConfig,
     /// Used to determine and report recursive mod inclusions
@@ -219,19 +219,15 @@ fn file_to_filemap(sess: &ParseSess, path: &Path, spanopt: Option<Span>)
 }
 
 /// Given a filemap, produce a sequence of token-trees
-pub fn filemap_to_tts(sess: &ParseSess, filemap: Rc<FileMap>)
-    -> Vec<tokenstream::TokenTree> {
-    // it appears to me that the cfg doesn't matter here... indeed,
-    // parsing tt's probably shouldn't require a parser at all.
-    let srdr = lexer::StringReader::new(&sess.span_diagnostic, filemap);
-    let mut p1 = Parser::new(sess, Box::new(srdr), None, false);
-    panictry!(p1.parse_all_token_trees())
+pub fn filemap_to_tts(sess: &ParseSess, filemap: Rc<FileMap>) -> Vec<tokenstream::TokenTree> {
+    let mut srdr = lexer::StringReader::new(sess, filemap);
+    srdr.real_token();
+    panictry!(srdr.parse_all_token_trees())
 }
 
 /// Given tts and the ParseSess, produce a parser
 pub fn tts_to_parser<'a>(sess: &'a ParseSess, tts: Vec<tokenstream::TokenTree>) -> Parser<'a> {
-    let trdr = lexer::new_tt_reader(&sess.span_diagnostic, None, tts);
-    let mut p = Parser::new(sess, Box::new(trdr), None, false);
+    let mut p = Parser::new(sess, tts, None, false);
     p.check_unknown_macro_variable();
     p
 }
diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index d1a683b0bd5b8..5dd772041e271 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -46,7 +46,7 @@ use ext::tt::macro_parser;
 use parse;
 use parse::classify;
 use parse::common::SeqSep;
-use parse::lexer::{Reader, TokenAndSpan};
+use parse::lexer::TokenAndSpan;
 use parse::obsolete::ObsoleteSyntax;
 use parse::token::{self, MatchNt, SubstNt};
 use parse::{new_sub_parser_from_file, ParseSess, Directory, DirectoryOwnership};
@@ -156,22 +156,6 @@ enum PrevTokenKind {
     Other,
 }
 
-// Simple circular buffer used for keeping few next tokens.
-#[derive(Default)]
-struct LookaheadBuffer {
-    buffer: [TokenAndSpan; LOOKAHEAD_BUFFER_CAPACITY],
-    start: usize,
-    end: usize,
-}
-
-const LOOKAHEAD_BUFFER_CAPACITY: usize = 8;
-
-impl LookaheadBuffer {
-    fn len(&self) -> usize {
-        (LOOKAHEAD_BUFFER_CAPACITY + self.end - self.start) % LOOKAHEAD_BUFFER_CAPACITY
-    }
-}
-
 /* ident is handled by common.rs */
 
 pub struct Parser<'a> {
@@ -184,19 +168,14 @@ pub struct Parser<'a> {
     pub prev_span: Span,
     /// the previous token kind
     prev_token_kind: PrevTokenKind,
-    lookahead_buffer: LookaheadBuffer,
-    pub tokens_consumed: usize,
     pub restrictions: Restrictions,
     pub quote_depth: usize, // not (yet) related to the quasiquoter
     parsing_token_tree: bool,
-    pub reader: Box<Reader+'a>,
     /// The set of seen errors about obsolete syntax. Used to suppress
     /// extra detail when the same error is seen twice
     pub obsolete_set: HashSet<ObsoleteSyntax>,
     /// Used to determine the path to externally loaded source files
     pub directory: Directory,
-    /// Stack of open delimiters and their spans. Used for error message.
-    pub open_braces: Vec<(token::DelimToken, Span)>,
     /// Name of the root module this parser originated from. If `None`, then the
     /// name is not known. This does not change while the parser is descending
     /// into modules, and sub-parsers have new values for this name.
@@ -204,7 +183,6 @@ pub struct Parser<'a> {
     pub expected_tokens: Vec<TokenType>,
     pub tts: Vec<(TokenTree, usize)>,
     pub desugar_doc_comments: bool,
-    pub allow_interpolated_tts: bool,
 }
 
 #[derive(PartialEq, Eq, Clone)]
@@ -270,30 +248,31 @@ impl From<P<Expr>> for LhsExpr {
 
 impl<'a> Parser<'a> {
     pub fn new(sess: &'a ParseSess,
-               rdr: Box<Reader+'a>,
+               tokens: Vec<TokenTree>,
                directory: Option<Directory>,
                desugar_doc_comments: bool)
                -> Self {
+        let tt = TokenTree::Delimited(syntax_pos::DUMMY_SP, Rc::new(Delimited {
+            delim: token::NoDelim,
+            open_span: syntax_pos::DUMMY_SP,
+            tts: tokens,
+            close_span: syntax_pos::DUMMY_SP,
+        }));
         let mut parser = Parser {
-            reader: rdr,
             sess: sess,
             token: token::Underscore,
             span: syntax_pos::DUMMY_SP,
             prev_span: syntax_pos::DUMMY_SP,
             prev_token_kind: PrevTokenKind::Other,
-            lookahead_buffer: Default::default(),
-            tokens_consumed: 0,
             restrictions: Restrictions::empty(),
             quote_depth: 0,
             parsing_token_tree: false,
             obsolete_set: HashSet::new(),
             directory: Directory { path: PathBuf::new(), ownership: DirectoryOwnership::Owned },
-            open_braces: Vec::new(),
             root_module_name: None,
             expected_tokens: Vec::new(),
-            tts: Vec::new(),
+            tts: if tt.len() > 0 { vec![(tt, 0)] } else { Vec::new() },
             desugar_doc_comments: desugar_doc_comments,
-            allow_interpolated_tts: true,
         };
 
         let tok = parser.next_tok();
@@ -309,8 +288,8 @@ impl<'a> Parser<'a> {
     }
 
     fn next_tok(&mut self) -> TokenAndSpan {
-        'outer: loop {
-            let mut tok = if let Some((tts, i)) = self.tts.pop() {
+        loop {
+            let tok = if let Some((tts, i)) = self.tts.pop() {
                 let tt = tts.get_tt(i);
                 if i + 1 < tts.len() {
                     self.tts.push((tts, i + 1));
@@ -322,28 +301,14 @@ impl<'a> Parser<'a> {
                     continue
                 }
             } else {
-                self.reader.real_token()
+                TokenAndSpan { tok: token::Eof, sp: self.span }
             };
 
-            loop {
-                let nt = match tok.tok {
-                    token::Interpolated(ref nt) => nt.clone(),
-                    token::DocComment(name) if self.desugar_doc_comments => {
-                        self.tts.push((TokenTree::Token(tok.sp, token::DocComment(name)), 0));
-                        continue 'outer
-                    }
-                    _ => return tok,
-                };
-                match *nt {
-                    token::NtTT(TokenTree::Token(sp, ref t)) => {
-                        tok = TokenAndSpan { tok: t.clone(), sp: sp };
-                    }
-                    token::NtTT(ref tt) => {
-                        self.tts.push((tt.clone(), 0));
-                        continue 'outer
-                    }
-                    _ => return tok,
+            match tok.tok {
+                token::DocComment(name) if self.desugar_doc_comments => {
+                    self.tts.push((TokenTree::Token(tok.sp, token::DocComment(name)), 0));
                 }
+                _ => return tok,
             }
         }
     }
@@ -892,17 +857,9 @@ impl<'a> Parser<'a> {
             _ => PrevTokenKind::Other,
         };
 
-        let next = if self.lookahead_buffer.start == self.lookahead_buffer.end {
-            self.next_tok()
-        } else {
-            // Avoid token copies with `replace`.
-            let old_start = self.lookahead_buffer.start;
-            self.lookahead_buffer.start = (old_start + 1) % LOOKAHEAD_BUFFER_CAPACITY;
-            mem::replace(&mut self.lookahead_buffer.buffer[old_start], Default::default())
-        };
+        let next = self.next_tok();
         self.span = next.sp;
         self.token = next.tok;
-        self.tokens_consumed += 1;
         self.expected_tokens.clear();
         // check after each token
         self.check_unknown_macro_variable();
@@ -935,18 +892,20 @@ impl<'a> Parser<'a> {
         F: FnOnce(&token::Token) -> R,
     {
         if dist == 0 {
-            f(&self.token)
-        } else if dist < LOOKAHEAD_BUFFER_CAPACITY {
-            while self.lookahead_buffer.len() < dist {
-                self.lookahead_buffer.buffer[self.lookahead_buffer.end] = self.next_tok();
-                self.lookahead_buffer.end =
-                    (self.lookahead_buffer.end + 1) % LOOKAHEAD_BUFFER_CAPACITY;
-            }
-            let index = (self.lookahead_buffer.start + dist - 1) % LOOKAHEAD_BUFFER_CAPACITY;
-            f(&self.lookahead_buffer.buffer[index].tok)
-        } else {
-            self.bug("lookahead distance is too large");
+            return f(&self.token);
+        }
+        let mut tok = token::Eof;
+        if let Some(&(ref tts, mut i)) = self.tts.last() {
+            i += dist - 1;
+            if i < tts.len() {
+                tok = match tts.get_tt(i) {
+                    TokenTree::Token(_, tok) => tok,
+                    TokenTree::Delimited(_, delimited) => token::OpenDelim(delimited.delim),
+                    TokenTree::Sequence(..) => token::Dollar,
+                };
+            }
         }
+        f(&tok)
     }
     pub fn fatal(&self, m: &str) -> DiagnosticBuilder<'a> {
         self.sess.span_diagnostic.struct_span_fatal(self.span, m)
@@ -1277,10 +1236,17 @@ impl<'a> Parser<'a> {
                           "at least one type parameter bound \
                           must be specified");
         }
-        if let TyKind::Path(None, ref path) = lhs.node {
+
+        let mut lhs = lhs.unwrap();
+        if let TyKind::Paren(ty) = lhs.node {
+            // We have to accept the first bound in parens for backward compatibility.
+            // Example: `(Bound) + Bound + Bound`
+            lhs = ty.unwrap();
+        }
+        if let TyKind::Path(None, path) = lhs.node {
             let poly_trait_ref = PolyTraitRef {
                 bound_lifetimes: Vec::new(),
-                trait_ref: TraitRef { path: path.clone(), ref_id: lhs.id },
+                trait_ref: TraitRef { path: path, ref_id: lhs.id },
                 span: lhs.span,
             };
             let poly_trait_ref = TraitTyParamBound(poly_trait_ref, TraitBoundModifier::None);
@@ -2743,94 +2709,28 @@ impl<'a> Parser<'a> {
         // whether something will be a nonterminal or a seq
         // yet.
         match self.token {
-            token::Eof => {
-                let mut err: DiagnosticBuilder<'a> =
-                    self.diagnostic().struct_span_err(self.span,
-                                                      "this file contains an un-closed delimiter");
-                for &(_, sp) in &self.open_braces {
-                    err.span_help(sp, "did you mean to close this delimiter?");
-                }
-
-                Err(err)
-            },
             token::OpenDelim(delim) => {
-                if self.tts.last().map(|&(_, i)| i == 1).unwrap_or(false) {
+                if self.quote_depth == 0 && self.tts.last().map(|&(_, i)| i == 1).unwrap_or(false) {
                     let tt = self.tts.pop().unwrap().0;
                     self.bump();
-                    return Ok(if self.allow_interpolated_tts {
-                        // avoid needlessly reparsing token trees in recursive macro expansions
-                        TokenTree::Token(tt.span(), token::Interpolated(Rc::new(token::NtTT(tt))))
-                    } else {
-                        tt
-                    });
+                    return Ok(tt);
                 }
 
                 let parsing_token_tree = ::std::mem::replace(&mut self.parsing_token_tree, true);
-                // The span for beginning of the delimited section
-                let pre_span = self.span;
-
-                // Parse the open delimiter.
-                self.open_braces.push((delim, self.span));
                 let open_span = self.span;
                 self.bump();
-
-                // Parse the token trees within the delimiters.
-                // We stop at any delimiter so we can try to recover if the user
-                // uses an incorrect delimiter.
                 let tts = self.parse_seq_to_before_tokens(&[&token::CloseDelim(token::Brace),
                                                             &token::CloseDelim(token::Paren),
                                                             &token::CloseDelim(token::Bracket)],
                                                           SeqSep::none(),
                                                           |p| p.parse_token_tree(),
                                                           |mut e| e.emit());
+                self.parsing_token_tree = parsing_token_tree;
 
                 let close_span = self.span;
-                // Expand to cover the entire delimited token tree
-                let span = Span { hi: close_span.hi, ..pre_span };
-
-                match self.token {
-                    // Correct delimiter.
-                    token::CloseDelim(d) if d == delim => {
-                        self.open_braces.pop().unwrap();
-
-                        // Parse the close delimiter.
-                        self.bump();
-                    }
-                    // Incorrect delimiter.
-                    token::CloseDelim(other) => {
-                        let token_str = self.this_token_to_string();
-                        let mut err = self.diagnostic().struct_span_err(self.span,
-                            &format!("incorrect close delimiter: `{}`", token_str));
-                        // This is a conservative error: only report the last unclosed delimiter.
-                        // The previous unclosed delimiters could actually be closed! The parser
-                        // just hasn't gotten to them yet.
-                        if let Some(&(_, sp)) = self.open_braces.last() {
-                            err.span_note(sp, "unclosed delimiter");
-                        };
-                        err.emit();
-
-                        self.open_braces.pop().unwrap();
-
-                        // If the incorrect delimiter matches an earlier opening
-                        // delimiter, then don't consume it (it can be used to
-                        // close the earlier one). Otherwise, consume it.
-                        // E.g., we try to recover from:
-                        // fn foo() {
-                        //     bar(baz(
-                        // }  // Incorrect delimiter but matches the earlier `{`
-                        if !self.open_braces.iter().any(|&(b, _)| b == other) {
-                            self.bump();
-                        }
-                    }
-                    token::Eof => {
-                        // Silently recover, the EOF token will be seen again
-                        // and an error emitted then. Thus we don't pop from
-                        // self.open_braces here.
-                    },
-                    _ => {}
-                }
+                self.bump();
 
-                self.parsing_token_tree = parsing_token_tree;
+                let span = Span { lo: open_span.lo, ..close_span };
                 Ok(TokenTree::Delimited(span, Rc::new(Delimited {
                     delim: delim,
                     open_span: open_span,
@@ -2838,21 +2738,9 @@ impl<'a> Parser<'a> {
                     close_span: close_span,
                 })))
             },
-            token::CloseDelim(_) => {
-                // An unexpected closing delimiter (i.e., there is no
-                // matching opening delimiter).
-                let token_str = self.this_token_to_string();
-                let err = self.diagnostic().struct_span_err(self.span,
-                    &format!("unexpected close delimiter: `{}`", token_str));
-                Err(err)
-            },
-            /* we ought to allow different depths of unquotation */
-            token::Dollar | token::SubstNt(..) if self.quote_depth > 0 => {
-                self.parse_unquoted()
-            }
-            _ => {
-                Ok(TokenTree::Token(self.span, self.bump_and_get()))
-            }
+            token::CloseDelim(_) | token::Eof => unreachable!(),
+            token::Dollar | token::SubstNt(..) if self.quote_depth > 0 => self.parse_unquoted(),
+            _ => Ok(TokenTree::Token(self.span, self.bump_and_get())),
         }
     }
 
diff --git a/src/libsyntax/print/pprust.rs b/src/libsyntax/print/pprust.rs
index baa3ebec85469..061e871fe5229 100644
--- a/src/libsyntax/print/pprust.rs
+++ b/src/libsyntax/print/pprust.rs
@@ -18,10 +18,9 @@ use util::parser::AssocOp;
 use attr;
 use codemap::{self, CodeMap};
 use syntax_pos::{self, BytePos};
-use errors;
 use parse::token::{self, BinOpToken, Token};
 use parse::lexer::comments;
-use parse;
+use parse::{self, ParseSess};
 use print::pp::{self, break_offset, word, space, zerobreak, hardbreak};
 use print::pp::{Breaks, eof};
 use print::pp::Breaks::{Consistent, Inconsistent};
@@ -101,20 +100,15 @@ pub const DEFAULT_COLUMNS: usize = 78;
 /// it can scan the input text for comments and literals to
 /// copy forward.
 pub fn print_crate<'a>(cm: &'a CodeMap,
-                       span_diagnostic: &errors::Handler,
+                       sess: &ParseSess,
                        krate: &ast::Crate,
                        filename: String,
                        input: &mut Read,
                        out: Box<Write+'a>,
                        ann: &'a PpAnn,
                        is_expanded: bool) -> io::Result<()> {
-    let mut s = State::new_from_input(cm,
-                                      span_diagnostic,
-                                      filename,
-                                      input,
-                                      out,
-                                      ann,
-                                      is_expanded);
+    let mut s = State::new_from_input(cm, sess, filename, input, out, ann, is_expanded);
+
     if is_expanded && !std_inject::injected_crate_name(krate).is_none() {
         // We need to print `#![no_std]` (and its feature gate) so that
         // compiling pretty-printed source won't inject libstd again.
@@ -140,16 +134,13 @@ pub fn print_crate<'a>(cm: &'a CodeMap,
 
 impl<'a> State<'a> {
     pub fn new_from_input(cm: &'a CodeMap,
-                          span_diagnostic: &errors::Handler,
+                          sess: &ParseSess,
                           filename: String,
                           input: &mut Read,
                           out: Box<Write+'a>,
                           ann: &'a PpAnn,
                           is_expanded: bool) -> State<'a> {
-        let (cmnts, lits) = comments::gather_comments_and_literals(
-            span_diagnostic,
-            filename,
-            input);
+        let (cmnts, lits) = comments::gather_comments_and_literals(sess, filename, input);
 
         State::new(
             cm,
diff --git a/src/libsyntax/tokenstream.rs b/src/libsyntax/tokenstream.rs
index e352e7853c71c..ab5dc8181e05b 100644
--- a/src/libsyntax/tokenstream.rs
+++ b/src/libsyntax/tokenstream.rs
@@ -30,7 +30,6 @@ use codemap::{Spanned, combine_spans};
 use ext::base;
 use ext::tt::macro_parser;
 use parse::lexer::comments::{doc_comment_style, strip_doc_comment_decoration};
-use parse::lexer;
 use parse::{self, Directory};
 use parse::token::{self, Token, Lit, Nonterminal};
 use print::pprust;
@@ -139,7 +138,10 @@ impl TokenTree {
                 if let Nonterminal::NtTT(..) = **nt { 1 } else { 0 }
             },
             TokenTree::Token(_, token::MatchNt(..)) => 3,
-            TokenTree::Delimited(_, ref delimed) => delimed.tts.len() + 2,
+            TokenTree::Delimited(_, ref delimed) => match delimed.delim {
+                token::NoDelim => delimed.tts.len(),
+                _ => delimed.tts.len() + 2,
+            },
             TokenTree::Sequence(_, ref seq) => seq.tts.len(),
             TokenTree::Token(..) => 0,
         }
@@ -181,6 +183,9 @@ impl TokenTree {
                     close_span: sp,
                 }))
             }
+            (&TokenTree::Delimited(_, ref delimed), _) if delimed.delim == token::NoDelim => {
+                delimed.tts[index].clone()
+            }
             (&TokenTree::Delimited(_, ref delimed), _) => {
                 if index == 0 {
                     return delimed.open_tt();
@@ -215,14 +220,12 @@ impl TokenTree {
                  mtch: &[TokenTree],
                  tts: &[TokenTree])
                  -> macro_parser::NamedParseResult {
-        let diag = &cx.parse_sess().span_diagnostic;
         // `None` is because we're not interpolating
-        let arg_rdr = lexer::new_tt_reader(diag, None, tts.iter().cloned().collect());
         let directory = Directory {
             path: cx.current_expansion.module.directory.clone(),
             ownership: cx.current_expansion.directory_ownership,
         };
-        macro_parser::parse(cx.parse_sess(), arg_rdr, mtch, Some(directory))
+        macro_parser::parse(cx.parse_sess(), tts.iter().cloned().collect(), mtch, Some(directory))
     }
 
     /// Check if this TokenTree is equal to the other, regardless of span information.
diff --git a/src/libsyntax_ext/deriving/custom.rs b/src/libsyntax_ext/deriving/custom.rs
index 64ec460a52460..2ce6fc03f7731 100644
--- a/src/libsyntax_ext/deriving/custom.rs
+++ b/src/libsyntax_ext/deriving/custom.rs
@@ -77,8 +77,9 @@ impl MultiItemModifier for CustomDerive {
             let inner = self.inner;
             panic::catch_unwind(panic::AssertUnwindSafe(|| inner(input)))
         });
-        let new_items = match res {
-            Ok(stream) => __internal::token_stream_items(stream),
+
+        let stream = match res {
+            Ok(stream) => stream,
             Err(e) => {
                 let msg = "custom derive attribute panicked";
                 let mut err = ecx.struct_span_fatal(span, msg);
@@ -94,6 +95,18 @@ impl MultiItemModifier for CustomDerive {
             }
         };
 
+        let new_items = __internal::set_parse_sess(&ecx.parse_sess, || {
+            match __internal::token_stream_parse_items(stream) {
+                Ok(new_items) => new_items,
+                Err(_) => {
+                    // FIXME: handle this better
+                    let msg = "custom derive produced unparseable tokens";
+                    ecx.struct_span_fatal(span, msg).emit();
+                    panic!(FatalError);
+                }
+            }
+        });
+
         let mut res = vec![Annotatable::Item(item)];
         // Reassign spans of all expanded items to the input `item`
         // for better errors here.
diff --git a/src/libsyntax_ext/lib.rs b/src/libsyntax_ext/lib.rs
index bdec86158a4ec..ebec23d0901a0 100644
--- a/src/libsyntax_ext/lib.rs
+++ b/src/libsyntax_ext/lib.rs
@@ -47,6 +47,8 @@ pub mod proc_macro_registrar;
 // for custom_derive
 pub mod deriving;
 
+pub mod proc_macro_impl;
+
 use std::rc::Rc;
 use syntax::ast;
 use syntax::ext::base::{MacroExpanderFn, NormalTT, MultiModifier, NamedSyntaxExtension};
diff --git a/src/libsyntax_ext/proc_macro_impl.rs b/src/libsyntax_ext/proc_macro_impl.rs
new file mode 100644
index 0000000000000..b454628acb1c0
--- /dev/null
+++ b/src/libsyntax_ext/proc_macro_impl.rs
@@ -0,0 +1,58 @@
+// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+use std::panic;
+
+use errors::FatalError;
+
+use syntax::codemap::Span;
+use syntax::ext::base::*;
+use syntax::tokenstream::TokenStream;
+use syntax::ext::base;
+
+use proc_macro::TokenStream as TsShim;
+use proc_macro::__internal;
+
+pub struct AttrProcMacro {
+    pub inner: fn(TsShim, TsShim) -> TsShim,
+}
+
+impl base::AttrProcMacro for AttrProcMacro {
+    fn expand<'cx>(&self,
+                   ecx: &'cx mut ExtCtxt,
+                   span: Span,
+                   annotation: TokenStream,
+                   annotated: TokenStream)
+                   -> TokenStream {
+        let annotation = __internal::token_stream_wrap(annotation);
+        let annotated = __internal::token_stream_wrap(annotated);
+
+        let res = __internal::set_parse_sess(&ecx.parse_sess, || {
+            panic::catch_unwind(panic::AssertUnwindSafe(|| (self.inner)(annotation, annotated)))
+        });
+
+        match res {
+            Ok(stream) => __internal::token_stream_inner(stream),
+            Err(e) => {
+                let msg = "custom attribute panicked";
+                let mut err = ecx.struct_span_fatal(span, msg);
+                if let Some(s) = e.downcast_ref::<String>() {
+                    err.help(&format!("message: {}", s));
+                }
+                if let Some(s) = e.downcast_ref::<&'static str>() {
+                    err.help(&format!("message: {}", s));
+                }
+
+                err.emit();
+                panic!(FatalError);
+            }
+        }
+    }
+}
diff --git a/src/libsyntax_ext/proc_macro_registrar.rs b/src/libsyntax_ext/proc_macro_registrar.rs
index c93e2c054d240..c8af16e9242f0 100644
--- a/src/libsyntax_ext/proc_macro_registrar.rs
+++ b/src/libsyntax_ext/proc_macro_registrar.rs
@@ -11,18 +11,20 @@
 use std::mem;
 
 use errors;
+
 use syntax::ast::{self, Ident, NodeId};
 use syntax::codemap::{ExpnInfo, NameAndSpan, MacroAttribute};
 use syntax::ext::base::ExtCtxt;
 use syntax::ext::build::AstBuilder;
 use syntax::ext::expand::ExpansionConfig;
-use syntax::parse::ParseSess;
 use syntax::fold::Folder;
+use syntax::parse::ParseSess;
 use syntax::ptr::P;
 use syntax::symbol::Symbol;
-use syntax_pos::{Span, DUMMY_SP};
 use syntax::visit::{self, Visitor};
 
+use syntax_pos::{Span, DUMMY_SP};
+
 use deriving;
 
 struct CustomDerive {
@@ -32,8 +34,14 @@ struct CustomDerive {
     attrs: Vec<ast::Name>,
 }
 
-struct CollectCustomDerives<'a> {
+struct AttrProcMacro {
+    function_name: Ident,
+    span: Span,
+}
+
+struct CollectProcMacros<'a> {
     derives: Vec<CustomDerive>,
+    attr_macros: Vec<AttrProcMacro>,
     in_root: bool,
     handler: &'a errors::Handler,
     is_proc_macro_crate: bool,
@@ -50,16 +58,17 @@ pub fn modify(sess: &ParseSess,
     let ecfg = ExpansionConfig::default("proc_macro".to_string());
     let mut cx = ExtCtxt::new(sess, ecfg, resolver);
 
-    let derives = {
-        let mut collect = CollectCustomDerives {
+    let (derives, attr_macros) = {
+        let mut collect = CollectProcMacros {
             derives: Vec::new(),
+            attr_macros: Vec::new(),
             in_root: true,
             handler: handler,
             is_proc_macro_crate: is_proc_macro_crate,
             is_test_crate: is_test_crate,
         };
         visit::walk_crate(&mut collect, &krate);
-        collect.derives
+        (collect.derives, collect.attr_macros)
     };
 
     if !is_proc_macro_crate {
@@ -74,7 +83,7 @@ pub fn modify(sess: &ParseSess,
         return krate;
     }
 
-    krate.module.items.push(mk_registrar(&mut cx, &derives));
+    krate.module.items.push(mk_registrar(&mut cx, &derives, &attr_macros));
 
     if krate.exported_macros.len() > 0 {
         handler.err("cannot export macro_rules! macros from a `proc-macro` \
@@ -84,7 +93,7 @@ pub fn modify(sess: &ParseSess,
     return krate
 }
 
-impl<'a> CollectCustomDerives<'a> {
+impl<'a> CollectProcMacros<'a> {
     fn check_not_pub_in_root(&self, vis: &ast::Visibility, sp: Span) {
         if self.is_proc_macro_crate &&
            self.in_root &&
@@ -92,61 +101,11 @@ impl<'a> CollectCustomDerives<'a> {
             self.handler.span_err(sp,
                                   "`proc-macro` crate types cannot \
                                    export any items other than functions \
-                                   tagged with `#[proc_macro_derive]` \
-                                   currently");
+                                   tagged with `#[proc_macro_derive]` currently");
         }
     }
-}
-
-impl<'a> Visitor<'a> for CollectCustomDerives<'a> {
-    fn visit_item(&mut self, item: &'a ast::Item) {
-        let mut attrs = item.attrs.iter().filter(|a| a.check_name("proc_macro_derive"));
-
-        // First up, make sure we're checking a bare function. If we're not then
-        // we're just not interested in this item.
-        //
-        // If we find one, try to locate a `#[proc_macro_derive]` attribute on
-        // it.
-        match item.node {
-            ast::ItemKind::Fn(..) => {}
-            _ => {
-                // Check for invalid use of proc_macro_derive
-                if let Some(attr) = attrs.next() {
-                    self.handler.span_err(attr.span(),
-                                          "the `#[proc_macro_derive]` \
-                                          attribute may only be used \
-                                          on bare functions");
-                    return;
-                }
-                self.check_not_pub_in_root(&item.vis, item.span);
-                return visit::walk_item(self, item)
-            }
-        }
-
-        let attr = match attrs.next() {
-            Some(attr) => attr,
-            None => {
-                self.check_not_pub_in_root(&item.vis, item.span);
-                return visit::walk_item(self, item)
-            }
-        };
-
-        if let Some(a) = attrs.next() {
-            self.handler.span_err(a.span(), "multiple `#[proc_macro_derive]` \
-                                             attributes found");
-        }
-
-        if self.is_test_crate {
-            return;
-        }
-
-        if !self.is_proc_macro_crate {
-            self.handler.span_err(attr.span(),
-                                  "the `#[proc_macro_derive]` attribute is \
-                                   only usable with crates of the `proc-macro` \
-                                   crate type");
-        }
 
+    fn collect_custom_derive(&mut self, item: &'a ast::Item, attr: &'a ast::Attribute) {
         // Once we've located the `#[proc_macro_derive]` attribute, verify
         // that it's of the form `#[proc_macro_derive(Foo)]` or
         // `#[proc_macro_derive(Foo, attributes(A, ..))]`
@@ -232,6 +191,101 @@ impl<'a> Visitor<'a> for CollectCustomDerives<'a> {
             };
             self.handler.span_err(item.span, msg);
         }
+    }
+
+    fn collect_attr_proc_macro(&mut self, item: &'a ast::Item, attr: &'a ast::Attribute) {
+        if let Some(_) = attr.meta_item_list() {
+            self.handler.span_err(attr.span, "`#[proc_macro_attribute]` attribute
+                cannot contain any meta items");
+            return;
+        }
+
+        if self.in_root && item.vis == ast::Visibility::Public {
+            self.attr_macros.push(AttrProcMacro {
+                span: item.span,
+                function_name: item.ident,
+            });
+        } else {
+            let msg = if !self.in_root {
+                "functions tagged with `#[proc_macro_attribute]` must \
+                 currently reside in the root of the crate"
+            } else {
+                "functions tagged with `#[proc_macro_attribute]` must be `pub`"
+            };
+            self.handler.span_err(item.span, msg);
+        }
+    }
+}
+
+impl<'a> Visitor<'a> for CollectProcMacros<'a> {
+    fn visit_item(&mut self, item: &'a ast::Item) {
+        // First up, make sure we're checking a bare function. If we're not then
+        // we're just not interested in this item.
+        //
+        // If we find one, try to locate a `#[proc_macro_derive]` attribute on
+        // it.
+        let is_fn = match item.node {
+            ast::ItemKind::Fn(..) => true,
+            _ => false,
+        };
+
+        let mut found_attr: Option<&'a ast::Attribute> = None;
+
+        for attr in &item.attrs {
+            if attr.check_name("proc_macro_derive") || attr.check_name("proc_macro_attribute") {
+                if let Some(prev_attr) = found_attr {
+                    let msg = if attr.name() == prev_attr.name() {
+                        format!("Only one `#[{}]` attribute is allowed on any given function",
+                                attr.name())
+                    } else {
+                        format!("`#[{}]` and `#[{}]` attributes cannot both be applied \
+                                to the same function", attr.name(), prev_attr.name())
+                    };
+
+                    self.handler.struct_span_err(attr.span(), &msg)
+                        .span_note(prev_attr.span(), "Previous attribute here")
+                        .emit();
+
+                    return;
+                }
+
+                found_attr = Some(attr);
+            }
+        }
+
+        let attr = match found_attr {
+            None => {
+                self.check_not_pub_in_root(&item.vis, item.span);
+                return visit::walk_item(self, item);
+            },
+            Some(attr) => attr,
+        };
+
+        if !is_fn {
+            let msg = format!("the `#[{}]` attribute may only be used on bare functions",
+                              attr.name());
+
+            self.handler.span_err(attr.span(), &msg);
+            return;
+        }
+
+        if self.is_test_crate {
+            return;
+        }
+
+        if !self.is_proc_macro_crate {
+            let msg = format!("the `#[{}]` attribute is only usable with crates of the \
+                              `proc-macro` crate type", attr.name());
+
+            self.handler.span_err(attr.span(), &msg);
+            return;
+        }
+
+        if attr.check_name("proc_macro_derive") {
+            self.collect_custom_derive(item, attr);
+        } else if attr.check_name("proc_macro_attribute") {
+            self.collect_attr_proc_macro(item, attr);
+        };
 
         visit::walk_item(self, item);
     }
@@ -265,7 +319,8 @@ impl<'a> Visitor<'a> for CollectCustomDerives<'a> {
 //          }
 //      }
 fn mk_registrar(cx: &mut ExtCtxt,
-                custom_derives: &[CustomDerive]) -> P<ast::Item> {
+                custom_derives: &[CustomDerive],
+                custom_attrs: &[AttrProcMacro]) -> P<ast::Item> {
     let eid = cx.codemap().record_expansion(ExpnInfo {
         call_site: DUMMY_SP,
         callee: NameAndSpan {
@@ -286,25 +341,36 @@ fn mk_registrar(cx: &mut ExtCtxt,
     let registry = Ident::from_str("Registry");
     let registrar = Ident::from_str("registrar");
     let register_custom_derive = Ident::from_str("register_custom_derive");
-    let stmts = custom_derives.iter().map(|cd| {
+    let register_attr_proc_macro = Ident::from_str("register_attr_proc_macro");
+
+    let mut stmts = custom_derives.iter().map(|cd| {
         let path = cx.path_global(cd.span, vec![cd.function_name]);
         let trait_name = cx.expr_str(cd.span, cd.trait_name);
         let attrs = cx.expr_vec_slice(
             span,
             cd.attrs.iter().map(|&s| cx.expr_str(cd.span, s)).collect::<Vec<_>>()
         );
-        (path, trait_name, attrs)
-    }).map(|(path, trait_name, attrs)| {
         let registrar = cx.expr_ident(span, registrar);
         let ufcs_path = cx.path(span, vec![proc_macro, __internal, registry,
                                            register_custom_derive]);
-        cx.expr_call(span,
-                     cx.expr_path(ufcs_path),
-                     vec![registrar, trait_name, cx.expr_path(path), attrs])
-    }).map(|expr| {
-        cx.stmt_expr(expr)
+
+        cx.stmt_expr(cx.expr_call(span, cx.expr_path(ufcs_path),
+                                  vec![registrar, trait_name, cx.expr_path(path), attrs]))
+
     }).collect::<Vec<_>>();
 
+    stmts.extend(custom_attrs.iter().map(|ca| {
+        let name = cx.expr_str(ca.span, ca.function_name.name);
+        let path = cx.path_global(ca.span, vec![ca.function_name]);
+        let registrar = cx.expr_ident(ca.span, registrar);
+
+        let ufcs_path = cx.path(span,
+                                vec![proc_macro, __internal, registry, register_attr_proc_macro]);
+
+        cx.stmt_expr(cx.expr_call(span, cx.expr_path(ufcs_path),
+                                  vec![registrar, name, cx.expr_path(path)]))
+    }));
+
     let path = cx.path(span, vec![proc_macro, __internal, registry]);
     let registrar_path = cx.ty_path(path);
     let arg_ty = cx.ty_rptr(span, registrar_path, None, ast::Mutability::Mutable);
diff --git a/src/test/codegen/fastcall-inreg.rs b/src/test/codegen/fastcall-inreg.rs
index e1dda4d2be084..1cbde9b1a7c77 100644
--- a/src/test/codegen/fastcall-inreg.rs
+++ b/src/test/codegen/fastcall-inreg.rs
@@ -53,6 +53,7 @@
 // ignore-shave
 // ignore-wasm32
 // ignore-wasm64
+// ignore-emscripten
 
 // compile-flags: -C no-prepopulate-passes
 
diff --git a/src/test/compile-fail-fulldeps/proc-macro/auxiliary/attr_proc_macro.rs b/src/test/compile-fail-fulldeps/proc-macro/auxiliary/attr_proc_macro.rs
new file mode 100644
index 0000000000000..db0c19e96f821
--- /dev/null
+++ b/src/test/compile-fail-fulldeps/proc-macro/auxiliary/attr_proc_macro.rs
@@ -0,0 +1,23 @@
+// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// force-host
+// no-prefer-dynamic
+#![feature(proc_macro)]
+#![crate_type = "proc-macro"]
+
+extern crate proc_macro;
+
+use proc_macro::TokenStream;
+
+#[proc_macro_attribute]
+pub fn attr_proc_macro(_: TokenStream, input: TokenStream) -> TokenStream {
+    input
+}
diff --git a/src/test/compile-fail-fulldeps/proc-macro/derive-bad.rs b/src/test/compile-fail-fulldeps/proc-macro/derive-bad.rs
index 0e4ac9fe1eaf5..a5359946c09c2 100644
--- a/src/test/compile-fail-fulldeps/proc-macro/derive-bad.rs
+++ b/src/test/compile-fail-fulldeps/proc-macro/derive-bad.rs
@@ -16,8 +16,7 @@ extern crate derive_bad;
 #[derive(
     A
 )]
-//~^^ ERROR: custom derive attribute panicked
-//~| HELP: called `Result::unwrap()` on an `Err` value: LexError
+//~^^ ERROR: custom derive produced unparseable tokens
 struct A;
 
 fn main() {}
diff --git a/src/test/compile-fail-fulldeps/proc-macro/feature-gate-proc_macro.rs b/src/test/compile-fail-fulldeps/proc-macro/feature-gate-proc_macro.rs
new file mode 100644
index 0000000000000..7e32800e0f9b8
--- /dev/null
+++ b/src/test/compile-fail-fulldeps/proc-macro/feature-gate-proc_macro.rs
@@ -0,0 +1,24 @@
+// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// aux-build:attr_proc_macro.rs
+// gate-test-proc_macro
+#![feature(use_extern_macros)]
+
+extern crate attr_proc_macro;
+use attr_proc_macro::attr_proc_macro;
+
+#[attr_proc_macro]
+//~^ ERROR: attribute procedural macros are experimental
+struct Foo;
+
+fn main() {
+    let _ = Foo;
+}
\ No newline at end of file
diff --git a/src/test/compile-fail-fulldeps/proc-macro/macro-use-attr.rs b/src/test/compile-fail-fulldeps/proc-macro/macro-use-attr.rs
new file mode 100644
index 0000000000000..76253487b51fc
--- /dev/null
+++ b/src/test/compile-fail-fulldeps/proc-macro/macro-use-attr.rs
@@ -0,0 +1,22 @@
+// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// aux-build:attr_proc_macro.rs
+#![feature(proc_macro)]
+
+#[macro_use] extern crate attr_proc_macro;
+
+#[attr_proc_macro]
+//~^ ERROR: attribute procedural macros cannot be imported with `#[macro_use]`
+struct Foo;
+
+fn main() {
+    let _ = Foo;
+}
diff --git a/src/test/compile-fail-fulldeps/proc-macro/proc-macro-custom-attr-mutex.rs b/src/test/compile-fail-fulldeps/proc-macro/proc-macro-custom-attr-mutex.rs
new file mode 100644
index 0000000000000..288cab71ff49c
--- /dev/null
+++ b/src/test/compile-fail-fulldeps/proc-macro/proc-macro-custom-attr-mutex.rs
@@ -0,0 +1,24 @@
+// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// aux-build:attr_proc_macro.rs
+
+#![feature(proc_macro, custom_attribute)]
+//~^ ERROR Cannot use `#![feature(proc_macro)]` and `#![feature(custom_attribute)] at the same time
+
+extern crate attr_proc_macro;
+use attr_proc_macro::attr_proc_macro;
+
+#[attr_proc_macro]
+fn foo() {}
+
+fn main() {
+    foo();
+}
diff --git a/src/test/compile-fail/asm-bad-clobber.rs b/src/test/compile-fail/asm-bad-clobber.rs
index 85832ddefe25f..cb931329051f9 100644
--- a/src/test/compile-fail/asm-bad-clobber.rs
+++ b/src/test/compile-fail/asm-bad-clobber.rs
@@ -12,6 +12,7 @@
 // ignore-arm
 // ignore-aarch64
 // ignore-s390x
+// ignore-emscripten
 
 #![feature(asm, rustc_attrs)]
 
diff --git a/src/test/compile-fail/asm-in-bad-modifier.rs b/src/test/compile-fail/asm-in-bad-modifier.rs
index a4d076fc90da2..7ba5beac21340 100644
--- a/src/test/compile-fail/asm-in-bad-modifier.rs
+++ b/src/test/compile-fail/asm-in-bad-modifier.rs
@@ -9,6 +9,7 @@
 // except according to those terms.
 
 // ignore-s390x
+// ignore-emscripten
 
 #![feature(asm)]
 
diff --git a/src/test/compile-fail/asm-misplaced-option.rs b/src/test/compile-fail/asm-misplaced-option.rs
index fbfc20f8d048a..bafbf625e3517 100644
--- a/src/test/compile-fail/asm-misplaced-option.rs
+++ b/src/test/compile-fail/asm-misplaced-option.rs
@@ -12,6 +12,7 @@
 // ignore-arm
 // ignore-aarch64
 // ignore-s390x
+// ignore-emscripten
 
 #![feature(asm, rustc_attrs)]
 
diff --git a/src/test/compile-fail/asm-out-assign-imm.rs b/src/test/compile-fail/asm-out-assign-imm.rs
index 1329959fe4938..161c0b977ff0c 100644
--- a/src/test/compile-fail/asm-out-assign-imm.rs
+++ b/src/test/compile-fail/asm-out-assign-imm.rs
@@ -9,6 +9,7 @@
 // except according to those terms.
 
 // ignore-s390x
+// ignore-emscripten
 
 #![feature(asm)]
 
diff --git a/src/test/compile-fail/asm-out-no-modifier.rs b/src/test/compile-fail/asm-out-no-modifier.rs
index d610f9e344024..cb8fb19a7c7f0 100644
--- a/src/test/compile-fail/asm-out-no-modifier.rs
+++ b/src/test/compile-fail/asm-out-no-modifier.rs
@@ -9,6 +9,7 @@
 // except according to those terms.
 
 // ignore-s390x
+// ignore-emscripten
 
 #![feature(asm)]
 
diff --git a/src/test/compile-fail/asm-out-read-uninit.rs b/src/test/compile-fail/asm-out-read-uninit.rs
index 360f89dda9ce3..42bff4c633aa9 100644
--- a/src/test/compile-fail/asm-out-read-uninit.rs
+++ b/src/test/compile-fail/asm-out-read-uninit.rs
@@ -9,6 +9,7 @@
 // except according to those terms.
 
 // ignore-s390x
+// ignore-emscripten
 
 #![feature(asm)]
 
diff --git a/src/test/compile-fail/asm-src-loc-codegen-units.rs b/src/test/compile-fail/asm-src-loc-codegen-units.rs
index 79f0c436759b3..df1a6d52f5739 100644
--- a/src/test/compile-fail/asm-src-loc-codegen-units.rs
+++ b/src/test/compile-fail/asm-src-loc-codegen-units.rs
@@ -12,6 +12,7 @@
 // ignore-stage1
 // compile-flags: -C codegen-units=2
 // error-pattern: build without -C codegen-units for more exact errors
+// ignore-emscripten
 
 #![feature(asm)]
 
diff --git a/src/test/compile-fail/asm-src-loc.rs b/src/test/compile-fail/asm-src-loc.rs
index e3cece7c8f0db..59b47c2408d7d 100644
--- a/src/test/compile-fail/asm-src-loc.rs
+++ b/src/test/compile-fail/asm-src-loc.rs
@@ -8,6 +8,8 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+// ignore-emscripten
+
 #![feature(asm)]
 
 fn main() {
diff --git a/src/test/compile-fail/auxiliary/import_crate_var.rs b/src/test/compile-fail/auxiliary/import_crate_var.rs
index 1dfc7a128aa1c..a8a55afa41a0e 100644
--- a/src/test/compile-fail/auxiliary/import_crate_var.rs
+++ b/src/test/compile-fail/auxiliary/import_crate_var.rs
@@ -8,5 +8,10 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+pub fn f() {}
+
 #[macro_export]
-macro_rules! m { () => { use $crate; } }
+macro_rules! m { () => {
+    use $crate;
+    import_crate_var::f();
+} }
diff --git a/src/test/compile-fail/cdylib-deps-must-be-static.rs b/src/test/compile-fail/cdylib-deps-must-be-static.rs
index 4b160f26e92ca..853507cbc6d8a 100644
--- a/src/test/compile-fail/cdylib-deps-must-be-static.rs
+++ b/src/test/compile-fail/cdylib-deps-must-be-static.rs
@@ -11,6 +11,7 @@
 // error-pattern: dependency `cdylib_dep` not found in rlib format
 // aux-build:cdylib-dep.rs
 // ignore-musl
+// ignore-emscripten
 
 #![crate_type = "cdylib"]
 
diff --git a/src/test/compile-fail/coherence-overlapping-inherent-impl-trait.rs b/src/test/compile-fail/coherence-overlapping-inherent-impl-trait.rs
new file mode 100644
index 0000000000000..08e8605e91773
--- /dev/null
+++ b/src/test/compile-fail/coherence-overlapping-inherent-impl-trait.rs
@@ -0,0 +1,18 @@
+// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![allow(dead_code)]
+#![deny(overlapping_inherent_impls)]
+
+trait C {}
+impl C { fn f() {} } //~ ERROR duplicate definitions with name `f`
+//~^ WARN: this was previously accepted
+impl C { fn f() {} }
+fn main() { }
diff --git a/src/test/compile-fail/const-fn-stability.rs b/src/test/compile-fail/const-fn-stability.rs
index 436244525e1c2..d093364497a92 100644
--- a/src/test/compile-fail/const-fn-stability.rs
+++ b/src/test/compile-fail/const-fn-stability.rs
@@ -16,7 +16,9 @@ const fn foo() -> usize { 0 } //~ ERROR const fn is unstable
 
 trait Foo {
     const fn foo() -> u32; //~ ERROR const fn is unstable
+                           //~| ERROR trait fns cannot be declared const
     const fn bar() -> u32 { 0 } //~ ERROR const fn is unstable
+                                //~| ERROR trait fns cannot be declared const
 }
 
 impl Foo {
@@ -25,6 +27,7 @@ impl Foo {
 
 impl Foo for u32 {
     const fn foo() -> u32 { 0 } //~ ERROR const fn is unstable
+                                //~| ERROR trait fns cannot be declared const
 }
 
 static FOO: usize = foo();
diff --git a/src/test/compile-fail/feature-gate-dropck-ugeh.rs b/src/test/compile-fail/feature-gate-dropck-ugeh.rs
index 360895d30b0b7..d9664fda2b339 100644
--- a/src/test/compile-fail/feature-gate-dropck-ugeh.rs
+++ b/src/test/compile-fail/feature-gate-dropck-ugeh.rs
@@ -28,6 +28,7 @@ struct Foo<T> { data: Vec<T> }
 impl<T> Drop for Foo<T> {
     #[unsafe_destructor_blind_to_params] // This is the UGEH attribute
     //~^ ERROR unsafe_destructor_blind_to_params has been replaced
+    //~^^ WARN: use of deprecated attribute
     fn drop(&mut self) { }
 }
 
diff --git a/src/test/compile-fail/feature-gate-no-debug.rs b/src/test/compile-fail/feature-gate-no-debug.rs
index e185056026c3c..9815db6550d66 100644
--- a/src/test/compile-fail/feature-gate-no-debug.rs
+++ b/src/test/compile-fail/feature-gate-no-debug.rs
@@ -8,5 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+#![allow(deprecated)]
+
 #[no_debug] //~ ERROR the `#[no_debug]` attribute is
 fn main() {}
diff --git a/src/test/compile-fail/import-crate-var.rs b/src/test/compile-fail/import-crate-var.rs
index 9f573945483de..e58ba2c88917f 100644
--- a/src/test/compile-fail/import-crate-var.rs
+++ b/src/test/compile-fail/import-crate-var.rs
@@ -11,11 +11,13 @@
 // aux-build:import_crate_var.rs
 // error-pattern: `$crate` may not be imported
 // error-pattern: `use $crate;` was erroneously allowed and will become a hard error
+// error-pattern: compilation successful
 
 #![feature(rustc_attrs)]
 
 #[macro_use] extern crate import_crate_var;
-m!();
 
 #[rustc_error]
-fn main() {}
+fn main() {
+    m!();
+}
diff --git a/src/test/compile-fail/issue-18937.rs b/src/test/compile-fail/issue-18937.rs
index 8ac66bb44d20a..f57f3477a8a86 100644
--- a/src/test/compile-fail/issue-18937.rs
+++ b/src/test/compile-fail/issue-18937.rs
@@ -10,8 +10,6 @@
 
 // Regression test for #18937.
 
-#![deny(extra_requirement_in_impl)]
-
 use std::fmt;
 
 #[derive(Debug)]
diff --git a/src/test/compile-fail/macro-expanded-include/test.rs b/src/test/compile-fail/macro-expanded-include/test.rs
index e1e85ddb2c1b1..bcc2c10653f9c 100644
--- a/src/test/compile-fail/macro-expanded-include/test.rs
+++ b/src/test/compile-fail/macro-expanded-include/test.rs
@@ -8,6 +8,8 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+// ignore-emscripten
+
 #![feature(asm, rustc_attrs)]
 #![allow(unused)]
 
diff --git a/src/test/compile-fail/panic-runtime/abort-link-to-unwind-dylib.rs b/src/test/compile-fail/panic-runtime/abort-link-to-unwind-dylib.rs
index c3242a5082b62..1fd60b15a72ac 100644
--- a/src/test/compile-fail/panic-runtime/abort-link-to-unwind-dylib.rs
+++ b/src/test/compile-fail/panic-runtime/abort-link-to-unwind-dylib.rs
@@ -10,6 +10,7 @@
 
 // compile-flags:-C panic=abort -C prefer-dynamic
 // ignore-musl - no dylibs here
+// ignore-emscripten
 // error-pattern:`panic_unwind` is not compiled with this crate's panic strategy
 
 // This is a test where the local crate, compiled with `panic=abort`, links to
diff --git a/src/test/compile-fail/two-allocators-3.rs b/src/test/compile-fail/two-allocators-3.rs
index 7782d0e338ef4..965e4e0e2eabe 100644
--- a/src/test/compile-fail/two-allocators-3.rs
+++ b/src/test/compile-fail/two-allocators-3.rs
@@ -11,6 +11,7 @@
 // aux-build:allocator1.rs
 // error-pattern: cannot link together two allocators
 // ignore-musl no dylibs on musl yet
+// ignore-emscripten
 
 // We're linking std dynamically (via -C prefer-dynamic for this test) which
 // has an allocator and then we're also linking in a new allocator (allocator1)
diff --git a/src/test/parse-fail/bounds-obj-parens.rs b/src/test/parse-fail/bounds-obj-parens.rs
new file mode 100644
index 0000000000000..cbdffb4a2554e
--- /dev/null
+++ b/src/test/parse-fail/bounds-obj-parens.rs
@@ -0,0 +1,15 @@
+// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// compile-flags: -Z parse-only
+
+type A = Box<(Fn(D::Error) -> E) + 'static + Send + Sync>; // OK
+
+FAIL //~ ERROR
diff --git a/src/test/parse-fail/issue-33569.rs b/src/test/parse-fail/issue-33569.rs
index 130278d778ab0..e3c17af82aab4 100644
--- a/src/test/parse-fail/issue-33569.rs
+++ b/src/test/parse-fail/issue-33569.rs
@@ -13,6 +13,6 @@
 macro_rules! foo {
     { $+ } => { //~ ERROR expected identifier, found `+`
         $(x)(y) //~ ERROR expected `*` or `+`
-                //~^ ERROR no rules expected the token `y`
+                //~^ ERROR no rules expected the token `)`
     }
 }
diff --git a/src/test/run-pass-fulldeps/proc-macro/attr-args.rs b/src/test/run-pass-fulldeps/proc-macro/attr-args.rs
new file mode 100644
index 0000000000000..d28d75d81a2fb
--- /dev/null
+++ b/src/test/run-pass-fulldeps/proc-macro/attr-args.rs
@@ -0,0 +1,24 @@
+// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// aux-build:attr-args.rs
+
+#![allow(warnings)]
+#![feature(proc_macro)]
+
+extern crate attr_args;
+use attr_args::attr_with_args;
+
+#[attr_with_args(text = "Hello, world!")]
+fn foo() {}
+
+fn main() {
+    assert_eq!(foo(), "Hello, world!");
+}
diff --git a/src/test/run-pass-fulldeps/proc-macro/auxiliary/attr-args.rs b/src/test/run-pass-fulldeps/proc-macro/auxiliary/attr-args.rs
new file mode 100644
index 0000000000000..6e1eb395a0a19
--- /dev/null
+++ b/src/test/run-pass-fulldeps/proc-macro/auxiliary/attr-args.rs
@@ -0,0 +1,32 @@
+// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// no-prefer-dynamic
+#![feature(proc_macro)]
+#![crate_type = "proc-macro"]
+
+extern crate proc_macro;
+
+use proc_macro::TokenStream;
+
+#[proc_macro_attribute]
+pub fn attr_with_args(args: TokenStream, input: TokenStream) -> TokenStream {
+    let args = args.to_string();
+
+    assert_eq!(args, r#"( text = "Hello, world!" )"#);
+
+    let input = input.to_string();
+
+    assert_eq!(input, "fn foo (  ) {  }");
+
+    r#"
+        fn foo() -> &'static str { "Hello, world!" }
+    "#.parse().unwrap()
+}
diff --git a/src/test/run-pass-fulldeps/proc-macro/auxiliary/derive-atob.rs b/src/test/run-pass-fulldeps/proc-macro/auxiliary/derive-atob.rs
index 713fb7d10f2fd..4624891c1a32d 100644
--- a/src/test/run-pass-fulldeps/proc-macro/auxiliary/derive-atob.rs
+++ b/src/test/run-pass-fulldeps/proc-macro/auxiliary/derive-atob.rs
@@ -19,6 +19,6 @@ use proc_macro::TokenStream;
 #[proc_macro_derive(AToB)]
 pub fn derive(input: TokenStream) -> TokenStream {
     let input = input.to_string();
-    assert_eq!(input, "#[derive(Copy, Clone)]\nstruct A;\n");
+    assert_eq!(input, "#[derive(Copy, Clone)]\nstruct A;");
     "struct B;".parse().unwrap()
 }
diff --git a/src/test/run-pass-fulldeps/proc-macro/auxiliary/derive-ctod.rs b/src/test/run-pass-fulldeps/proc-macro/auxiliary/derive-ctod.rs
index 19caafd17b5f3..550ffe9400db8 100644
--- a/src/test/run-pass-fulldeps/proc-macro/auxiliary/derive-ctod.rs
+++ b/src/test/run-pass-fulldeps/proc-macro/auxiliary/derive-ctod.rs
@@ -19,6 +19,6 @@ use proc_macro::TokenStream;
 #[proc_macro_derive(CToD)]
 pub fn derive(input: TokenStream) -> TokenStream {
     let input = input.to_string();
-    assert_eq!(input, "struct C;\n");
+    assert_eq!(input, "struct C;");
     "struct D;".parse().unwrap()
 }
diff --git a/src/test/run-pass-fulldeps/proc-macro/auxiliary/derive-same-struct.rs b/src/test/run-pass-fulldeps/proc-macro/auxiliary/derive-same-struct.rs
index a2c25ae50e8ec..cf96f52823f0f 100644
--- a/src/test/run-pass-fulldeps/proc-macro/auxiliary/derive-same-struct.rs
+++ b/src/test/run-pass-fulldeps/proc-macro/auxiliary/derive-same-struct.rs
@@ -18,12 +18,12 @@ use proc_macro::TokenStream;
 #[proc_macro_derive(AToB)]
 pub fn derive1(input: TokenStream) -> TokenStream {
     println!("input1: {:?}", input.to_string());
-    assert_eq!(input.to_string(), "struct A;\n");
+    assert_eq!(input.to_string(), "struct A;");
     "#[derive(BToC)] struct B;".parse().unwrap()
 }
 
 #[proc_macro_derive(BToC)]
 pub fn derive2(input: TokenStream) -> TokenStream {
-    assert_eq!(input.to_string(), "struct B;\n");
+    assert_eq!(input.to_string(), "struct B;");
     "struct C;".parse().unwrap()
 }
diff --git a/src/test/run-pass-valgrind/down-with-thread-dtors.rs b/src/test/run-pass-valgrind/down-with-thread-dtors.rs
index 0bf10c67d9fc2..90c20444842f4 100644
--- a/src/test/run-pass-valgrind/down-with-thread-dtors.rs
+++ b/src/test/run-pass-valgrind/down-with-thread-dtors.rs
@@ -9,6 +9,7 @@
 // except according to those terms.
 
 // no-prefer-dynamic
+// ignore-emscripten
 
 thread_local!(static FOO: Foo = Foo);
 thread_local!(static BAR: Bar = Bar(1));
diff --git a/src/test/run-pass-valgrind/exit-flushes.rs b/src/test/run-pass-valgrind/exit-flushes.rs
index 1897b92140182..b72d2659967c4 100644
--- a/src/test/run-pass-valgrind/exit-flushes.rs
+++ b/src/test/run-pass-valgrind/exit-flushes.rs
@@ -11,6 +11,7 @@
 // no-prefer-dynamic
 // ignore-macos this needs valgrind 3.11 or higher; see
 // https://github.com/rust-lang/rust/pull/30365#issuecomment-165763679
+// ignore-emscripten
 
 use std::env;
 use std::process::{exit, Command};
diff --git a/src/test/run-pass/auxiliary/debuginfo-lto-aux.rs b/src/test/run-pass/auxiliary/debuginfo-lto-aux.rs
new file mode 100644
index 0000000000000..88e54d30172bc
--- /dev/null
+++ b/src/test/run-pass/auxiliary/debuginfo-lto-aux.rs
@@ -0,0 +1,39 @@
+// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// compile-flags: -g --crate-type=rlib
+
+pub struct StructWithLifetime<'a>(&'a i32);
+pub fn mk_struct_with_lt<'a>(x: &'a i32) -> StructWithLifetime<'a> {
+    StructWithLifetime(x)
+}
+
+pub struct RegularStruct(u32);
+pub fn mk_regular_struct(x: u32) -> RegularStruct {
+    RegularStruct(x)
+}
+
+pub fn take_fn(f: fn(i32) -> i32, x: i32) -> i32 {
+    f(x)
+}
+
+pub fn with_closure(x: i32) -> i32 {
+    let closure = |i| { x + i };
+
+    closure(1) + closure(2)
+}
+
+pub fn generic_fn<T>(x: T) -> (T, u32) {
+    (x, 1)
+}
+
+pub fn user_of_generic_fn(x: f32) -> (f32, u32) {
+    generic_fn(x)
+}
diff --git a/src/test/run-pass/auxiliary/sepcomp_lib.rs b/src/test/run-pass/auxiliary/sepcomp_lib.rs
index 9aa16fb269457..6f48978a0000d 100644
--- a/src/test/run-pass/auxiliary/sepcomp_lib.rs
+++ b/src/test/run-pass/auxiliary/sepcomp_lib.rs
@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// compile-flags: -C codegen-units=3 --crate-type=rlib,dylib
+// compile-flags: -C codegen-units=3 --crate-type=rlib,dylib -g
 
 pub mod a {
     pub fn one() -> usize {
diff --git a/src/test/run-pass/debuginfo-lto.rs b/src/test/run-pass/debuginfo-lto.rs
new file mode 100644
index 0000000000000..c29cfafe438ca
--- /dev/null
+++ b/src/test/run-pass/debuginfo-lto.rs
@@ -0,0 +1,33 @@
+// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// This test case makes sure that we don't run into LLVM's dreaded
+// "possible ODR violation" assertion when compiling with LTO + Debuginfo.
+// It covers cases that have traditionally been prone to cause this error.
+// If new cases emerge, add them to this file.
+
+// aux-build:debuginfo-lto-aux.rs
+// compile-flags: -C lto -g
+// no-prefer-dynamic
+
+extern crate debuginfo_lto_aux;
+
+fn some_fn(x: i32) -> i32 {
+    x + 1
+}
+
+fn main() {
+    let i = 0;
+    let _ = debuginfo_lto_aux::mk_struct_with_lt(&i);
+    let _ = debuginfo_lto_aux::mk_regular_struct(1);
+    let _ = debuginfo_lto_aux::take_fn(some_fn, 1);
+    let _ = debuginfo_lto_aux::with_closure(22);
+    let _ = debuginfo_lto_aux::generic_fn(0f32);
+}
diff --git a/src/test/run-pass/i128-ffi.rs b/src/test/run-pass/i128-ffi.rs
index 3b5f4884d21e7..222f32754fb6b 100644
--- a/src/test/run-pass/i128-ffi.rs
+++ b/src/test/run-pass/i128-ffi.rs
@@ -20,6 +20,8 @@
 // Ignore 32 bit targets:
 // ignore-x86, ignore-arm
 
+// ignore-emscripten
+
 #![feature(i128_type)]
 
 #[link(name = "rust_test_helpers", kind = "static")]
diff --git a/src/test/run-pass/i128.rs b/src/test/run-pass/i128.rs
index a4ff36d20e4fa..3eb1c95050267 100644
--- a/src/test/run-pass/i128.rs
+++ b/src/test/run-pass/i128.rs
@@ -10,6 +10,9 @@
 
 // ignore-stage0
 // ignore-stage1
+
+// ignore-emscripten
+
 #![feature(i128_type, test)]
 
 extern crate test;
diff --git a/src/test/run-pass/issue-21634.rs b/src/test/run-pass/issue-21634.rs
index 2a146ae8fcf7b..08cc993ce4fb2 100644
--- a/src/test/run-pass/issue-21634.rs
+++ b/src/test/run-pass/issue-21634.rs
@@ -8,8 +8,9 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+#![feature(cfg_target_feature)]
 
-
+#[cfg(any(not(target_arch = "x86"), target_feature = "sse2"))]
 fn main() {
     if let Ok(x) = "3.1415".parse::<f64>() {
         assert_eq!(false, x <= 0.0);
@@ -21,3 +22,6 @@ fn main() {
         assert_eq!(8.1415, { x += 5.0; x });
     }
 }
+
+#[cfg(all(target_arch = "x86", not(target_feature = "sse2")))]
+fn main() {}
diff --git a/src/test/run-pass/issue-38942.rs b/src/test/run-pass/issue-38942.rs
new file mode 100644
index 0000000000000..9c1c999d090ef
--- /dev/null
+++ b/src/test/run-pass/issue-38942.rs
@@ -0,0 +1,26 @@
+// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// See https://github.com/rust-lang/rust/issues/38942
+
+#[repr(u64)]
+pub enum NSEventType {
+    NSEventTypePressure,
+}
+
+pub const A: u64 = NSEventType::NSEventTypePressure as u64;
+
+fn banana() -> u64 {
+    A
+}
+
+fn main() {
+    println!("banana! {}", banana());
+}
diff --git a/src/test/run-pass/issue-39089.rs b/src/test/run-pass/issue-39089.rs
new file mode 100644
index 0000000000000..c3a58844547d6
--- /dev/null
+++ b/src/test/run-pass/issue-39089.rs
@@ -0,0 +1,13 @@
+// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+fn f<T: ?for<'a> Sized>() {}
+
+fn main() {}
diff --git a/src/test/run-pass/sepcomp-lib-lto.rs b/src/test/run-pass/sepcomp-lib-lto.rs
index b159b128333f0..f3e52fbd32f3e 100644
--- a/src/test/run-pass/sepcomp-lib-lto.rs
+++ b/src/test/run-pass/sepcomp-lib-lto.rs
@@ -12,7 +12,7 @@
 // separately compiled.
 
 // aux-build:sepcomp_lib.rs
-// compile-flags: -C lto
+// compile-flags: -C lto -g
 // no-prefer-dynamic
 // ignore-android FIXME #18800
 
diff --git a/src/test/run-pass/sse2.rs b/src/test/run-pass/sse2.rs
index 78d91b2f3120e..8d88c17af79b3 100644
--- a/src/test/run-pass/sse2.rs
+++ b/src/test/run-pass/sse2.rs
@@ -10,9 +10,20 @@
 
 #![feature(cfg_target_feature)]
 
-pub fn main() {
+use std::env;
+
+fn main() {
+    match env::var("TARGET") {
+        Ok(s) => {
+            // Skip this tests on i586-unknown-linux-gnu where sse2 is disabled
+            if s.contains("i586") {
+                return
+            }
+        }
+        Err(_) => return,
+    }
     if cfg!(any(target_arch = "x86", target_arch = "x86_64")) {
         assert!(cfg!(target_feature = "sse2"),
-            "SSE2 was not detected as available on an x86 platform");
+                "SSE2 was not detected as available on an x86 platform");
     }
 }
diff --git a/src/test/run-pass/stdio-is-blocking.rs b/src/test/run-pass/stdio-is-blocking.rs
index 74170ca6506ec..448bb7de7727f 100644
--- a/src/test/run-pass/stdio-is-blocking.rs
+++ b/src/test/run-pass/stdio-is-blocking.rs
@@ -8,6 +8,8 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+// ignore-emscripten
+
 use std::env;
 use std::io::prelude::*;
 use std::process::Command;
diff --git a/src/test/run-pass/try-wait.rs b/src/test/run-pass/try-wait.rs
index fdaf0cfd5b0c8..d9826373cceb0 100644
--- a/src/test/run-pass/try-wait.rs
+++ b/src/test/run-pass/try-wait.rs
@@ -8,6 +8,8 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+// ignore-emscripten
+
 #![feature(process_try_wait)]
 
 use std::env;
diff --git a/src/test/run-pass/u128.rs b/src/test/run-pass/u128.rs
index 53d726f1f663b..139d42e3a3524 100644
--- a/src/test/run-pass/u128.rs
+++ b/src/test/run-pass/u128.rs
@@ -10,6 +10,9 @@
 
 // ignore-stage0
 // ignore-stage1
+
+// ignore-emscripten
+
 #![feature(i128_type, test)]
 
 extern crate test;
diff --git a/src/test/ui/compare-method/proj-outlives-region.stderr b/src/test/ui/compare-method/proj-outlives-region.stderr
index 79293e0deed60..021b571fe793c 100644
--- a/src/test/ui/compare-method/proj-outlives-region.stderr
+++ b/src/test/ui/compare-method/proj-outlives-region.stderr
@@ -1,4 +1,4 @@
-error[E0276]: impl has stricter requirements than trait
+error[E0276]: impl has stricter requirements than trait, #[deny(extra_requirement_in_impl)] on by default
   --> $DIR/proj-outlives-region.rs:22:5
    |
 17 |     fn foo() where T: 'a;
@@ -9,11 +9,6 @@ error[E0276]: impl has stricter requirements than trait
    |
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
    = note: for more information, see issue #37166 <https://github.com/rust-lang/rust/issues/37166>
-note: lint level defined here
-  --> $DIR/proj-outlives-region.rs:12:9
-   |
-12 | #![deny(extra_requirement_in_impl)]
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/compare-method/region-unrelated.stderr b/src/test/ui/compare-method/region-unrelated.stderr
index b7cfdf799bc9d..4df337c525743 100644
--- a/src/test/ui/compare-method/region-unrelated.stderr
+++ b/src/test/ui/compare-method/region-unrelated.stderr
@@ -1,4 +1,4 @@
-error[E0276]: impl has stricter requirements than trait
+error[E0276]: impl has stricter requirements than trait, #[deny(extra_requirement_in_impl)] on by default
   --> $DIR/region-unrelated.rs:22:5
    |
 17 |     fn foo() where T: 'a;
@@ -9,11 +9,6 @@ error[E0276]: impl has stricter requirements than trait
    |
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
    = note: for more information, see issue #37166 <https://github.com/rust-lang/rust/issues/37166>
-note: lint level defined here
-  --> $DIR/region-unrelated.rs:12:9
-   |
-12 | #![deny(extra_requirement_in_impl)]
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/resolve/enums-are-namespaced-xc.stderr b/src/test/ui/resolve/enums-are-namespaced-xc.stderr
index 204c574a3a996..d541aa599a48b 100644
--- a/src/test/ui/resolve/enums-are-namespaced-xc.stderr
+++ b/src/test/ui/resolve/enums-are-namespaced-xc.stderr
@@ -5,7 +5,7 @@ error[E0425]: cannot find value `A` in module `namespaced_enums`
    |             ^^^^^^^^^^^^^^^^^^^ not found in `namespaced_enums`
    |
    = help: possible candidate is found in another module, you can import it into scope:
-   = help:   `use namespaced_enums::Foo::A;`
+             `use namespaced_enums::Foo::A;`
 
 error[E0425]: cannot find function `B` in module `namespaced_enums`
   --> $DIR/enums-are-namespaced-xc.rs:18:13
@@ -14,7 +14,7 @@ error[E0425]: cannot find function `B` in module `namespaced_enums`
    |             ^^^^^^^^^^^^^^^^^^^ not found in `namespaced_enums`
    |
    = help: possible candidate is found in another module, you can import it into scope:
-   = help:   `use namespaced_enums::Foo::B;`
+             `use namespaced_enums::Foo::B;`
 
 error[E0422]: cannot find struct, variant or union type `C` in module `namespaced_enums`
   --> $DIR/enums-are-namespaced-xc.rs:21:13
@@ -23,7 +23,7 @@ error[E0422]: cannot find struct, variant or union type `C` in module `namespace
    |             ^^^^^^^^^^^^^^^^^^^ not found in `namespaced_enums`
    |
    = help: possible candidate is found in another module, you can import it into scope:
-   = help:   `use namespaced_enums::Foo::C;`
+             `use namespaced_enums::Foo::C;`
 
 error: aborting due to 3 previous errors
 
diff --git a/src/test/ui/resolve/issue-16058.stderr b/src/test/ui/resolve/issue-16058.stderr
index 6b00cfb869316..69c48cc1f3241 100644
--- a/src/test/ui/resolve/issue-16058.stderr
+++ b/src/test/ui/resolve/issue-16058.stderr
@@ -5,9 +5,9 @@ error[E0574]: expected struct, variant or union type, found enum `Result`
    |         ^^^^^^ not a struct, variant or union type
    |
    = help: possible better candidates are found in other modules, you can import them into scope:
-   = help:   `use std::fmt::Result;`
-   = help:   `use std::io::Result;`
-   = help:   `use std::thread::Result;`
+             `use std::fmt::Result;`
+             `use std::io::Result;`
+             `use std::thread::Result;`
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/resolve/issue-17518.stderr b/src/test/ui/resolve/issue-17518.stderr
index 335510ed7e9d5..ea6841e600972 100644
--- a/src/test/ui/resolve/issue-17518.stderr
+++ b/src/test/ui/resolve/issue-17518.stderr
@@ -5,7 +5,7 @@ error[E0422]: cannot find struct, variant or union type `E` in this scope
    |     ^ not found in this scope
    |
    = help: possible candidate is found in another module, you can import it into scope:
-   = help:   `use SomeEnum::E;`
+             `use SomeEnum::E;`
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/resolve/issue-21221-1.stderr b/src/test/ui/resolve/issue-21221-1.stderr
index d9c2f9e681eee..f38491d536258 100644
--- a/src/test/ui/resolve/issue-21221-1.stderr
+++ b/src/test/ui/resolve/issue-21221-1.stderr
@@ -5,9 +5,9 @@ error[E0405]: cannot find trait `Mul` in this scope
    |      ^^^ not found in this scope
    |
    = help: possible candidates are found in other modules, you can import them into scope:
-   = help:   `use mul1::Mul;`
-   = help:   `use mul2::Mul;`
-   = help:   `use std::ops::Mul;`
+             `use mul1::Mul;`
+             `use mul2::Mul;`
+             `use std::ops::Mul;`
 
 error[E0412]: cannot find type `Mul` in this scope
   --> $DIR/issue-21221-1.rs:72:16
@@ -16,11 +16,11 @@ error[E0412]: cannot find type `Mul` in this scope
    |                ^^^ not found in this scope
    |
    = help: possible candidates are found in other modules, you can import them into scope:
-   = help:   `use mul1::Mul;`
-   = help:   `use mul2::Mul;`
-   = help:   `use mul3::Mul;`
-   = help:   `use mul4::Mul;`
-   = help:   and 2 other candidates
+             `use mul1::Mul;`
+             `use mul2::Mul;`
+             `use mul3::Mul;`
+             `use mul4::Mul;`
+           and 2 other candidates
 
 error[E0405]: cannot find trait `ThisTraitReallyDoesntExistInAnyModuleReally` in this scope
   --> $DIR/issue-21221-1.rs:83:6
@@ -35,7 +35,7 @@ error[E0405]: cannot find trait `Div` in this scope
    |      ^^^ not found in this scope
    |
    = help: possible candidate is found in another module, you can import it into scope:
-   = help:   `use std::ops::Div;`
+             `use std::ops::Div;`
 
 error: cannot continue compilation due to previous error
 
diff --git a/src/test/ui/resolve/issue-21221-2.stderr b/src/test/ui/resolve/issue-21221-2.stderr
index eb5b1ab6918a9..14dac7de4b2e1 100644
--- a/src/test/ui/resolve/issue-21221-2.stderr
+++ b/src/test/ui/resolve/issue-21221-2.stderr
@@ -5,7 +5,7 @@ error[E0405]: cannot find trait `T` in this scope
    |      ^ not found in this scope
    |
    = help: possible candidate is found in another module, you can import it into scope:
-   = help:   `use foo::bar::T;`
+             `use foo::bar::T;`
 
 error: main function not found
 
diff --git a/src/test/ui/resolve/issue-21221-3.stderr b/src/test/ui/resolve/issue-21221-3.stderr
index 3594e9105a276..e1e00571e5d4a 100644
--- a/src/test/ui/resolve/issue-21221-3.stderr
+++ b/src/test/ui/resolve/issue-21221-3.stderr
@@ -5,7 +5,7 @@ error[E0405]: cannot find trait `OuterTrait` in this scope
    |      ^^^^^^^^^^ not found in this scope
    |
    = help: possible candidate is found in another module, you can import it into scope:
-   = help:   `use issue_21221_3::outer::OuterTrait;`
+             `use issue_21221_3::outer::OuterTrait;`
 
 error: cannot continue compilation due to previous error
 
diff --git a/src/test/ui/resolve/issue-21221-4.stderr b/src/test/ui/resolve/issue-21221-4.stderr
index 98486e5743cc9..569315a59cf34 100644
--- a/src/test/ui/resolve/issue-21221-4.stderr
+++ b/src/test/ui/resolve/issue-21221-4.stderr
@@ -5,7 +5,7 @@ error[E0405]: cannot find trait `T` in this scope
    |      ^ not found in this scope
    |
    = help: possible candidate is found in another module, you can import it into scope:
-   = help:   `use issue_21221_4::T;`
+             `use issue_21221_4::T;`
 
 error: cannot continue compilation due to previous error
 
diff --git a/src/test/ui/resolve/issue-3907.stderr b/src/test/ui/resolve/issue-3907.stderr
index 0a402680aa8be..a7dd494d75b0d 100644
--- a/src/test/ui/resolve/issue-3907.stderr
+++ b/src/test/ui/resolve/issue-3907.stderr
@@ -5,7 +5,7 @@ error[E0404]: expected trait, found type alias `Foo`
    |      ^^^ type aliases cannot be used for traits
    |
    = help: possible better candidate is found in another module, you can import it into scope:
-   = help:   `use issue_3907::Foo;`
+             `use issue_3907::Foo;`
 
 error: cannot continue compilation due to previous error
 
diff --git a/src/test/ui/span/issue-35987.stderr b/src/test/ui/span/issue-35987.stderr
index 764f34cabde9a..9dab2f7789815 100644
--- a/src/test/ui/span/issue-35987.stderr
+++ b/src/test/ui/span/issue-35987.stderr
@@ -5,7 +5,7 @@ error[E0404]: expected trait, found type parameter `Add`
    |                     ^^^ not a trait
    |
    = help: possible better candidate is found in another module, you can import it into scope:
-   = help:   `use std::ops::Add;`
+             `use std::ops::Add;`
 
 error: main function not found
 
diff --git a/src/tools/compiletest/src/main.rs b/src/tools/compiletest/src/main.rs
index 8c9982d1d4e39..43d02479fb17d 100644
--- a/src/tools/compiletest/src/main.rs
+++ b/src/tools/compiletest/src/main.rs
@@ -319,6 +319,10 @@ pub fn run_tests(config: &Config) {
     // Prevent issue #21352 UAC blocking .exe containing 'patch' etc. on Windows
     // If #11207 is resolved (adding manifest to .exe) this becomes unnecessary
     env::set_var("__COMPAT_LAYER", "RunAsInvoker");
+
+    // Let tests know which target they're running as
+    env::set_var("TARGET", &config.target);
+
     let res = test::run_tests_console(&opts, tests.into_iter().collect());
     match res {
         Ok(true) => {}
diff --git a/src/tools/compiletest/src/util.rs b/src/tools/compiletest/src/util.rs
index cad71c59f0a4a..4202356bd97a0 100644
--- a/src/tools/compiletest/src/util.rs
+++ b/src/tools/compiletest/src/util.rs
@@ -12,39 +12,44 @@ use std::env;
 use common::Config;
 
 /// Conversion table from triple OS name to Rust SYSNAME
-const OS_TABLE: &'static [(&'static str, &'static str)] = &[("android", "android"),
-                                                            ("bitrig", "bitrig"),
-                                                            ("darwin", "macos"),
-                                                            ("dragonfly", "dragonfly"),
-                                                            ("freebsd", "freebsd"),
-                                                            ("haiku", "haiku"),
-                                                            ("ios", "ios"),
-                                                            ("linux", "linux"),
-                                                            ("mingw32", "windows"),
-                                                            ("netbsd", "netbsd"),
-                                                            ("openbsd", "openbsd"),
-                                                            ("win32", "windows"),
-                                                            ("windows", "windows"),
-                                                            ("solaris", "solaris"),
-                                                            ("emscripten", "emscripten")];
+const OS_TABLE: &'static [(&'static str, &'static str)] = &[
+    ("android", "android"),
+    ("bitrig", "bitrig"),
+    ("darwin", "macos"),
+    ("dragonfly", "dragonfly"),
+    ("freebsd", "freebsd"),
+    ("haiku", "haiku"),
+    ("ios", "ios"),
+    ("linux", "linux"),
+    ("mingw32", "windows"),
+    ("netbsd", "netbsd"),
+    ("openbsd", "openbsd"),
+    ("win32", "windows"),
+    ("windows", "windows"),
+    ("solaris", "solaris"),
+    ("emscripten", "emscripten"),
+];
 
-const ARCH_TABLE: &'static [(&'static str, &'static str)] = &[("aarch64", "aarch64"),
-                                                              ("amd64", "x86_64"),
-                                                              ("arm", "arm"),
-                                                              ("arm64", "aarch64"),
-                                                              ("hexagon", "hexagon"),
-                                                              ("i386", "x86"),
-                                                              ("i686", "x86"),
-                                                              ("mips", "mips"),
-                                                              ("msp430", "msp430"),
-                                                              ("powerpc", "powerpc"),
-                                                              ("powerpc64", "powerpc64"),
-                                                              ("s390x", "s390x"),
-                                                              ("sparc", "sparc"),
-                                                              ("x86_64", "x86_64"),
-                                                              ("xcore", "xcore"),
-                                                              ("asmjs", "asmjs"),
-                                                              ("wasm32", "wasm32")];
+const ARCH_TABLE: &'static [(&'static str, &'static str)] = &[
+    ("aarch64", "aarch64"),
+    ("amd64", "x86_64"),
+    ("arm", "arm"),
+    ("arm64", "aarch64"),
+    ("hexagon", "hexagon"),
+    ("i386", "x86"),
+    ("i586", "x86"),
+    ("i686", "x86"),
+    ("mips", "mips"),
+    ("msp430", "msp430"),
+    ("powerpc", "powerpc"),
+    ("powerpc64", "powerpc64"),
+    ("s390x", "s390x"),
+    ("sparc", "sparc"),
+    ("x86_64", "x86_64"),
+    ("xcore", "xcore"),
+    ("asmjs", "asmjs"),
+    ("wasm32", "wasm32"),
+];
 
 pub fn get_os(triple: &str) -> &'static str {
     for &(triple_os, os) in OS_TABLE {
diff --git a/src/tools/tidy/src/features.rs b/src/tools/tidy/src/features.rs
index 10b509d58bf73..9e365456a6c0d 100644
--- a/src/tools/tidy/src/features.rs
+++ b/src/tools/tidy/src/features.rs
@@ -172,7 +172,7 @@ pub fn check(path: &Path, bad: &mut bool) {
         "use_extern_macros", "staged_api", "const_indexing",
         "unboxed_closures", "stmt_expr_attributes",
         "cfg_target_thread_local", "unwind_attributes",
-        "inclusive_range_syntax"
+        "inclusive_range_syntax", "proc_macro"
     ];
 
     // Only check the number of lang features.