Rollup merge of #56718 - RalfJung:use-libbacktrace-printing, r=alexcrichton

Use libbacktrace pretty-printing

r? @alexcrichton
diff --git a/.gitmodules b/.gitmodules
index 3fc6e45..70164d4 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -5,9 +5,6 @@
 [submodule "src/rust-installer"]
 	path = src/tools/rust-installer
 	url = https://github.com/rust-lang/rust-installer.git
-[submodule "src/liblibc"]
-	path = src/liblibc
-	url = https://github.com/rust-lang/libc.git
 [submodule "src/doc/nomicon"]
 	path = src/doc/nomicon
 	url = https://github.com/rust-lang-nursery/nomicon.git
@@ -23,9 +20,6 @@
 [submodule "src/tools/rls"]
 	path = src/tools/rls
 	url = https://github.com/rust-lang-nursery/rls.git
-[submodule "src/libcompiler_builtins"]
-	path = src/libcompiler_builtins
-	url = https://github.com/rust-lang-nursery/compiler-builtins.git
 [submodule "src/tools/clippy"]
 	path = src/tools/clippy
 	url = https://github.com/rust-lang-nursery/rust-clippy.git
@@ -35,9 +29,6 @@
 [submodule "src/tools/miri"]
 	path = src/tools/miri
 	url = https://github.com/solson/miri.git
-[submodule "src/dlmalloc"]
-	path = src/dlmalloc
-	url = https://github.com/alexcrichton/dlmalloc-rs.git
 [submodule "src/doc/rust-by-example"]
 	path = src/doc/rust-by-example
 	url = https://github.com/rust-lang/rust-by-example.git
@@ -67,6 +58,3 @@
 [submodule "src/doc/edition-guide"]
 	path = src/doc/edition-guide
 	url = https://github.com/rust-lang-nursery/edition-guide
-[submodule "src/rust-sgx"]
-	path = src/rust-sgx
-	url = https://github.com/fortanix/rust-sgx
diff --git a/Cargo.lock b/Cargo.lock
index cdfa29d..be4a1c2 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -15,9 +15,9 @@
 name = "alloc"
 version = "0.0.0"
 dependencies = [
- "compiler_builtins 0.0.0",
+ "compiler_builtins 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
- "rand 0.5.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -407,10 +407,11 @@
 
 [[package]]
 name = "compiler_builtins"
-version = "0.0.0"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "cc 1.0.25 (registry+https://github.com/rust-lang/crates.io-index)",
- "core 0.0.0",
+ "rustc-std-workspace-core 1.0.0",
 ]
 
 [[package]]
@@ -456,7 +457,7 @@
 name = "core"
 version = "0.0.0"
 dependencies = [
- "rand 0.5.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -658,10 +659,12 @@
 
 [[package]]
 name = "dlmalloc"
-version = "0.0.0"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "compiler_builtins 0.0.0",
- "core 0.0.0",
+ "compiler_builtins 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.45 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-std-workspace-core 1.0.0",
 ]
 
 [[package]]
@@ -814,10 +817,11 @@
 
 [[package]]
 name = "fortanix-sgx-abi"
-version = "0.0.0"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "compiler_builtins 0.0.0",
- "core 0.0.0",
+ "compiler_builtins 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-std-workspace-core 1.0.0",
 ]
 
 [[package]]
@@ -1140,16 +1144,11 @@
 
 [[package]]
 name = "libc"
-version = "0.0.0"
-dependencies = [
- "compiler_builtins 0.0.0",
- "core 0.0.0",
-]
-
-[[package]]
-name = "libc"
 version = "0.2.45"
 source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "rustc-std-workspace-core 1.0.0",
+]
 
 [[package]]
 name = "libgit2-sys"
@@ -1520,9 +1519,9 @@
 name = "panic_abort"
 version = "0.0.0"
 dependencies = [
- "compiler_builtins 0.0.0",
+ "compiler_builtins 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
- "libc 0.0.0",
+ "libc 0.2.45 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -1530,9 +1529,9 @@
 version = "0.0.0"
 dependencies = [
  "alloc 0.0.0",
- "compiler_builtins 0.0.0",
+ "compiler_builtins 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
- "libc 0.0.0",
+ "libc 0.2.45 (registry+https://github.com/rust-lang/crates.io-index)",
  "unwind 0.0.0",
 ]
 
@@ -1683,7 +1682,7 @@
 version = "0.0.0"
 dependencies = [
  "cc 1.0.25 (registry+https://github.com/rust-lang/crates.io-index)",
- "compiler_builtins 0.0.0",
+ "compiler_builtins 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
 ]
 
@@ -1814,7 +1813,7 @@
 version = "0.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "rand_core 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc_version 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -1836,7 +1835,7 @@
 version = "0.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "rand_core 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -1861,7 +1860,7 @@
 version = "0.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "rand_core 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -2243,6 +2242,13 @@
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "rustc-std-workspace-core"
+version = "1.0.0"
+dependencies = [
+ "core 0.0.0",
+]
+
+[[package]]
 name = "rustc-workspace-hack"
 version = "1.0.0"
 dependencies = [
@@ -2284,7 +2290,7 @@
  "alloc 0.0.0",
  "build_helper 0.1.0",
  "cmake 0.1.33 (registry+https://github.com/rust-lang/crates.io-index)",
- "compiler_builtins 0.0.0",
+ "compiler_builtins 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
 ]
 
@@ -2479,7 +2485,7 @@
  "alloc 0.0.0",
  "build_helper 0.1.0",
  "cmake 0.1.33 (registry+https://github.com/rust-lang/crates.io-index)",
- "compiler_builtins 0.0.0",
+ "compiler_builtins 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
 ]
 
@@ -2531,7 +2537,7 @@
  "alloc 0.0.0",
  "build_helper 0.1.0",
  "cmake 0.1.33 (registry+https://github.com/rust-lang/crates.io-index)",
- "compiler_builtins 0.0.0",
+ "compiler_builtins 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
 ]
 
@@ -2644,7 +2650,7 @@
  "alloc 0.0.0",
  "build_helper 0.1.0",
  "cmake 0.1.33 (registry+https://github.com/rust-lang/crates.io-index)",
- "compiler_builtins 0.0.0",
+ "compiler_builtins 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
 ]
 
@@ -2877,15 +2883,15 @@
  "alloc 0.0.0",
  "build_helper 0.1.0",
  "cc 1.0.25 (registry+https://github.com/rust-lang/crates.io-index)",
- "compiler_builtins 0.0.0",
+ "compiler_builtins 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
- "dlmalloc 0.0.0",
- "fortanix-sgx-abi 0.0.0",
- "libc 0.0.0",
+ "dlmalloc 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "fortanix-sgx-abi 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.45 (registry+https://github.com/rust-lang/crates.io-index)",
  "panic_abort 0.0.0",
  "panic_unwind 0.0.0",
  "profiler_builtins 0.0.0",
- "rand 0.5.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc_asan 0.0.0",
  "rustc_lsan 0.0.0",
  "rustc_msan 0.0.0",
@@ -3217,9 +3223,9 @@
 name = "unwind"
 version = "0.0.0"
 dependencies = [
- "compiler_builtins 0.0.0",
+ "compiler_builtins 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
- "libc 0.0.0",
+ "libc 0.2.45 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -3397,6 +3403,7 @@
 "checksum colored 1.6.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b0aa3473e85a3161b59845d6096b289bb577874cafeaf75ea1b1beaa6572c7fc"
 "checksum commoncrypto 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d056a8586ba25a1e4d61cb090900e495952c7886786fc55f909ab2f819b69007"
 "checksum commoncrypto-sys 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "1fed34f46747aa73dfaa578069fd8279d2818ade2b55f38f22a9401c7f4083e2"
+"checksum compiler_builtins 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "8ad611263b9f31bdb66e66227d3b781600fd1e68d5deee29b23f5e2ac9cb4892"
 "checksum compiletest_rs 0.3.17 (registry+https://github.com/rust-lang/crates.io-index)" = "89747fe073b7838343bd2c2445e7a7c2e0d415598f8925f0fa9205b9cdfc48cb"
 "checksum core-foundation 0.6.3 (registry+https://github.com/rust-lang/crates.io-index)" = "4e2640d6d0bf22e82bed1b73c6aef8d5dd31e5abe6666c57e6d45e2649f4f887"
 "checksum core-foundation-sys 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)" = "e7ca8a5221364ef15ce201e8ed2f609fc312682a8f4e0e3d4aa5879764e0fa3b"
@@ -3418,6 +3425,7 @@
 "checksum diff 0.1.11 (registry+https://github.com/rust-lang/crates.io-index)" = "3c2b69f912779fbb121ceb775d74d51e915af17aaebc38d28a592843a2dd0a3a"
 "checksum difference 2.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "524cbf6897b527295dff137cec09ecf3a05f4fddffd7dfcd1585403449e74198"
 "checksum directories 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "72d337a64190607d4fcca2cb78982c5dd57f4916e19696b48a575fa746b6cb0f"
+"checksum dlmalloc 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "4c46c65de42b063004b31c67a98abe071089b289ff0919c660ed7ff4f59317f8"
 "checksum either 1.5.0 (registry+https://github.com/rust-lang/crates.io-index)" = "3be565ca5c557d7f59e7cfcf1844f9e3033650c929c6566f511e8005f205c1d0"
 "checksum elasticlunr-rs 2.3.4 (registry+https://github.com/rust-lang/crates.io-index)" = "a99a310cd1f9770e7bf8e48810c7bcbb0e078c8fb23a8c7bcf0da4c2bf61a455"
 "checksum ena 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)" = "f56c93cc076508c549d9bb747f79aa9b4eb098be7b8cad8830c3137ef52d1e00"
@@ -3434,6 +3442,7 @@
 "checksum fnv 1.0.6 (registry+https://github.com/rust-lang/crates.io-index)" = "2fad85553e09a6f881f739c29f0b00b0f01357c743266d478b68951ce23285f3"
 "checksum foreign-types 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)" = "f6f339eb8adc052cd2ca78910fda869aefa38d22d5cb648e6485e4d3fc06f3b1"
 "checksum foreign-types-shared 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "00b0228411908ca8685dba7fc2cdd70ec9990a6e753e89b6ac91a84c40fbaf4b"
+"checksum fortanix-sgx-abi 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "26105e20b4c3f7a319db1376b54ac9a46e5761e949405553375095d05a0cee4d"
 "checksum fs2 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)" = "9564fc758e15025b46aa6643b1b77d047d1a56a1aea6e01002ac0c7026876213"
 "checksum fs_extra 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "5f2a4a2034423744d2cc7ca2068453168dcdb82c438419e639a26bd87839c674"
 "checksum fst 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d94485a00b1827b861dd9d1a2cc9764f9044d4c535514c0760a5a2012ef3399f"
diff --git a/Cargo.toml b/Cargo.toml
index b763caa..667c557 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -65,6 +65,10 @@
 # here
 rustc-workspace-hack = { path = 'src/tools/rustc-workspace-hack' }
 
+# See comments in `tools/rustc-std-workspace-core/README.md` for what's going on
+# here
+rustc-std-workspace-core = { path = 'src/tools/rustc-std-workspace-core' }
+
 [patch."https://github.com/rust-lang/rust-clippy"]
 clippy_lints = { path = "src/tools/clippy/clippy_lints" }
 rustc_tools_util = { path = "src/tools/clippy/rustc_tools_util" }
diff --git a/src/bootstrap/builder.rs b/src/bootstrap/builder.rs
index 7dc64db..32f3e57 100644
--- a/src/bootstrap/builder.rs
+++ b/src/bootstrap/builder.rs
@@ -684,6 +684,11 @@
             .env("RUSTDOC_REAL", self.rustdoc(host))
             .env("RUSTDOC_CRATE_VERSION", self.rust_version())
             .env("RUSTC_BOOTSTRAP", "1");
+
+        // Remove make-related flags that can cause jobserver problems.
+        cmd.env_remove("MAKEFLAGS");
+        cmd.env_remove("MFLAGS");
+
         if let Some(linker) = self.linker(host) {
             cmd.env("RUSTC_TARGET_LINKER", linker);
         }
diff --git a/src/bootstrap/channel.rs b/src/bootstrap/channel.rs
index 88b6925..878b6ed 100644
--- a/src/bootstrap/channel.rs
+++ b/src/bootstrap/channel.rs
@@ -24,7 +24,7 @@
 use config::Config;
 
 // The version number
-pub const CFG_RELEASE_NUM: &str = "1.32.0";
+pub const CFG_RELEASE_NUM: &str = "1.33.0";
 
 pub struct GitInfo {
     inner: Option<Info>,
diff --git a/src/bootstrap/compile.rs b/src/bootstrap/compile.rs
index 2e792b6..689d053 100644
--- a/src/bootstrap/compile.rs
+++ b/src/bootstrap/compile.rs
@@ -152,11 +152,12 @@
 
     if builder.no_std(target) == Some(true) {
         // for no-std targets we only compile a few no_std crates
-        cargo.arg("--features").arg("c mem")
+        cargo
             .args(&["-p", "alloc"])
-            .args(&["-p", "compiler_builtins"])
             .arg("--manifest-path")
-            .arg(builder.src.join("src/rustc/compiler_builtins_shim/Cargo.toml"));
+            .arg(builder.src.join("src/liballoc/Cargo.toml"))
+            .arg("--features")
+            .arg("compiler-builtins-mem");
     } else {
         let features = builder.std_features();
 
diff --git a/src/bootstrap/dist.rs b/src/bootstrap/dist.rs
index 1ae494b..f03eefb 100644
--- a/src/bootstrap/dist.rs
+++ b/src/bootstrap/dist.rs
@@ -857,12 +857,9 @@
         // (essentially libstd and all of its path dependencies)
         let std_src_dirs = [
             "src/build_helper",
-            "src/dlmalloc",
             "src/liballoc",
             "src/libbacktrace",
-            "src/libcompiler_builtins",
             "src/libcore",
-            "src/liblibc",
             "src/libpanic_abort",
             "src/libpanic_unwind",
             "src/librustc_asan",
@@ -871,21 +868,15 @@
             "src/librustc_tsan",
             "src/libstd",
             "src/libunwind",
-            "src/rustc/compiler_builtins_shim",
-            "src/rustc/libc_shim",
-            "src/rustc/dlmalloc_shim",
-            "src/rustc/fortanix-sgx-abi_shim",
             "src/libtest",
             "src/libterm",
             "src/libprofiler_builtins",
             "src/stdsimd",
             "src/libproc_macro",
-        ];
-        let std_src_dirs_exclude = [
-            "src/libcompiler_builtins/compiler-rt/test",
+            "src/tools/rustc-std-workspace-core",
         ];
 
-        copy_src_dirs(builder, &std_src_dirs[..], &std_src_dirs_exclude[..], &dst_src);
+        copy_src_dirs(builder, &std_src_dirs[..], &[], &dst_src);
         for file in src_files.iter() {
             builder.copy(&builder.src.join(file), &dst_src.join(file));
         }
@@ -909,7 +900,7 @@
     }
 }
 
-const CARGO_VENDOR_VERSION: &str = "0.1.19";
+const CARGO_VENDOR_VERSION: &str = "0.1.22";
 
 #[derive(Debug, PartialOrd, Ord, Copy, Clone, Hash, PartialEq, Eq)]
 pub struct PlainSourceTarball;
diff --git a/src/bootstrap/lib.rs b/src/bootstrap/lib.rs
index c31db48..c879291 100644
--- a/src/bootstrap/lib.rs
+++ b/src/bootstrap/lib.rs
@@ -1134,10 +1134,10 @@
             let krate = &self.crates[&krate];
             if krate.is_local(self) {
                 ret.push(krate);
-                for dep in &krate.deps {
-                    if visited.insert(dep) && dep != "build_helper" {
-                        list.push(*dep);
-                    }
+            }
+            for dep in &krate.deps {
+                if visited.insert(dep) && dep != "build_helper" {
+                    list.push(*dep);
                 }
             }
         }
diff --git a/src/bootstrap/test.rs b/src/bootstrap/test.rs
index ca9894f..dc061fe 100644
--- a/src/bootstrap/test.rs
+++ b/src/bootstrap/test.rs
@@ -1558,10 +1558,7 @@
         let builder = run.builder;
         run = run.krate("test");
         for krate in run.builder.in_tree_crates("std") {
-            if krate.is_local(&run.builder)
-                && !(krate.name.starts_with("rustc_") && krate.name.ends_with("san"))
-                && krate.name != "dlmalloc"
-            {
+            if !(krate.name.starts_with("rustc_") && krate.name.ends_with("san")) {
                 run = run.path(krate.local_path(&builder).to_str().unwrap());
             }
         }
diff --git a/src/build_helper/lib.rs b/src/build_helper/lib.rs
index 0cbb080..a580a87 100644
--- a/src/build_helper/lib.rs
+++ b/src/build_helper/lib.rs
@@ -224,14 +224,12 @@
 // Timestamps are created automatically when the result of `native_lib_boilerplate` goes out
 // of scope, so all the build actions should be completed until then.
 pub fn native_lib_boilerplate(
-    src_name: &str,
+    src_dir: &Path,
     out_name: &str,
     link_name: &str,
     search_subdir: &str,
 ) -> Result<NativeLibBoilerplate, ()> {
-    let current_dir = PathBuf::from(env::var("CARGO_MANIFEST_DIR").unwrap());
-    let src_dir = current_dir.join("..").join(src_name);
-    rerun_if_changed_anything_in_dir(&src_dir);
+    rerun_if_changed_anything_in_dir(src_dir);
 
     let out_dir = env::var_os("RUSTBUILD_NATIVE_DIR").unwrap_or_else(||
         env::var_os("OUT_DIR").unwrap());
@@ -248,9 +246,9 @@
     );
 
     let timestamp = out_dir.join("rustbuild.timestamp");
-    if !up_to_date(Path::new("build.rs"), &timestamp) || !up_to_date(&src_dir, &timestamp) {
+    if !up_to_date(Path::new("build.rs"), &timestamp) || !up_to_date(src_dir, &timestamp) {
         Ok(NativeLibBoilerplate {
-            src_dir: src_dir,
+            src_dir: src_dir.to_path_buf(),
             out_dir: out_dir,
         })
     } else {
@@ -279,8 +277,11 @@
     } else {
         format!("static={}", link_name)
     };
+    // The source for `compiler-rt` comes from the `compiler-builtins` crate, so
+    // load our env var set by cargo to find the source code.
+    let dir = env::var_os("DEP_COMPILER_RT_COMPILER_RT").unwrap();
     let lib = native_lib_boilerplate(
-        "libcompiler_builtins/compiler-rt",
+        dir.as_ref(),
         sanitizer_name,
         &to_link,
         search_path,
diff --git a/src/dlmalloc b/src/dlmalloc
deleted file mode 160000
index de99f4b..0000000
--- a/src/dlmalloc
+++ /dev/null
@@ -1 +0,0 @@
-Subproject commit de99f4b0c886f5916cd1a146464276d65bef61b8
diff --git a/src/doc/rustc/src/codegen-options/index.md b/src/doc/rustc/src/codegen-options/index.md
index 4fc5f42..94f2104 100644
--- a/src/doc/rustc/src/codegen-options/index.md
+++ b/src/doc/rustc/src/codegen-options/index.md
@@ -22,6 +22,13 @@
 This flag lets you append multiple extra arguments to the linker invocation. The
 options should be separated by spaces.
 
+## linker-flavor
+
+This flag lets you control the linker flavor used by `rustc`. If a linker is given with the
+`-C linker` flag described above then the linker flavor is inferred from the value provided. If no
+linker is given then the linker flavor is used to determine the linker to use. Every `rustc` target
+defaults to some linker flavor.
+
 ## link-dead-code
 
 Normally, the linker will remove dead code. This flag disables this behavior.
diff --git a/src/doc/unstable-book/src/compiler-flags/linker-flavor.md b/src/doc/unstable-book/src/compiler-flags/linker-flavor.md
deleted file mode 100644
index 3965960..0000000
--- a/src/doc/unstable-book/src/compiler-flags/linker-flavor.md
+++ /dev/null
@@ -1,61 +0,0 @@
-# `linker-flavor`
-
-The tracking issue for this feature is: None
-
-------------------------
-
-Every `rustc` target defaults to some linker. For example, Linux targets default
-to gcc. In some cases, you may want to override the default; you can do that
-with the unstable CLI argument: `-Z linker-flavor`.
-
-Here how you would use this flag to link a Rust binary for the
-`thumbv7m-none-eabi` using LLD instead of GCC.
-
-``` text
-$ xargo rustc --target thumbv7m-none-eabi -- \
-    -C linker=ld.lld \
-    -Z linker-flavor=ld \
-    -Z print-link-args | tr ' ' '\n'
-"ld.lld"
-"-L"
-"$SYSROOT/lib/rustlib/thumbv7m-none-eabi/lib"
-"$PWD/target/thumbv7m-none-eabi/debug/deps/app-512e9dbf385f233c.0.o"
-"-o"
-"$PWD/target/thumbv7m-none-eabi/debug/deps/app-512e9dbf385f233c"
-"--gc-sections"
-"-L"
-"$PWD/target/thumbv7m-none-eabi/debug/deps"
-"-L"
-"$PWD/target/debug/deps"
-"-L"
-"$SYSROOT/lib/rustlib/thumbv7m-none-eabi/lib"
-"-Bstatic"
-"$SYSROOT/lib/rustlib/thumbv7m-none-eabi/lib/libcore-e1ccb7dfb1cb9ebb.rlib"
-"-Bdynamic"
-```
-
-Whereas the default is:
-
-``` text
-$ xargo rustc --target thumbv7m-none-eabi -- \
-    -C link-arg=-nostartfiles \
-    -Z print-link-args | tr ' ' '\n'
-"arm-none-eabi-gcc"
-"-L"
-"$SYSROOT/lib/rustlib/thumbv7m-none-eabi/lib"
-"$PWD/target/thumbv7m-none-eabi/debug/deps/app-961e39416baa38d9.0.o"
-"-o"
-"$PWD/target/thumbv7m-none-eabi/debug/deps/app-961e39416baa38d9"
-"-Wl,--gc-sections"
-"-nodefaultlibs"
-"-L"
-"$PWD/target/thumbv7m-none-eabi/debug/deps"
-"-L"
-"$PWD/target/debug/deps"
-"-L"
-"$SYSROOT/lib/rustlib/thumbv7m-none-eabi/lib"
-"-Wl,-Bstatic"
-"$SYSROOT/lib/rustlib/thumbv7m-none-eabi/lib/libcore-e1ccb7dfb1cb9ebb.rlib"
-"-nostartfiles"
-"-Wl,-Bdynamic"
-```
diff --git a/src/etc/gdb_rust_pretty_printing.py b/src/etc/gdb_rust_pretty_printing.py
index a376c85..f02c7d8 100755
--- a/src/etc/gdb_rust_pretty_printing.py
+++ b/src/etc/gdb_rust_pretty_printing.py
@@ -9,6 +9,7 @@
 # except according to those terms.
 
 import gdb
+import re
 import sys
 import debugger_pretty_printers_common as rustpp
 
@@ -20,6 +21,16 @@
 
 rust_enabled = 'set language rust' in gdb.execute('complete set language ru', to_string = True)
 
+# The btree pretty-printers fail in a confusing way unless
+# https://sourceware.org/bugzilla/show_bug.cgi?id=21763 is fixed.
+# This fix went in 8.1, so check for that.
+# See https://github.com/rust-lang/rust/issues/56730
+gdb_81 = False
+_match = re.match('([0-9]+)\\.([0-9]+)', gdb.VERSION)
+if _match:
+    if int(_match.group(1)) > 8 or (int(_match.group(1)) == 8 and int(_match.group(2)) >= 1):
+        gdb_81 = True
+
 #===============================================================================
 # GDB Pretty Printing Module for Rust
 #===============================================================================
@@ -110,10 +121,10 @@
     if type_kind == rustpp.TYPE_KIND_STD_VECDEQUE:
         return RustStdVecDequePrinter(val)
 
-    if type_kind == rustpp.TYPE_KIND_STD_BTREESET:
+    if type_kind == rustpp.TYPE_KIND_STD_BTREESET and gdb_81:
         return RustStdBTreeSetPrinter(val)
 
-    if type_kind == rustpp.TYPE_KIND_STD_BTREEMAP:
+    if type_kind == rustpp.TYPE_KIND_STD_BTREEMAP and gdb_81:
         return RustStdBTreeMapPrinter(val)
 
     if type_kind == rustpp.TYPE_KIND_STD_STRING:
diff --git a/src/liballoc/Cargo.toml b/src/liballoc/Cargo.toml
index 642a43d..b2eb356 100644
--- a/src/liballoc/Cargo.toml
+++ b/src/liballoc/Cargo.toml
@@ -11,10 +11,10 @@
 
 [dependencies]
 core = { path = "../libcore" }
-compiler_builtins = { path = "../rustc/compiler_builtins_shim" }
+compiler_builtins = { version = "0.1.0", features = ['rustc-dep-of-std'] }
 
 [dev-dependencies]
-rand = "0.5"
+rand = "0.6"
 
 [[test]]
 name = "collectionstests"
@@ -28,3 +28,6 @@
 name = "vec_deque_append_bench"
 path = "../liballoc/benches/vec_deque_append.rs"
 harness = false
+
+[features]
+compiler-builtins-mem = ['compiler_builtins/mem']
diff --git a/src/liballoc/collections/vec_deque.rs b/src/liballoc/collections/vec_deque.rs
index c0adeca..0c5926f 100644
--- a/src/liballoc/collections/vec_deque.rs
+++ b/src/liballoc/collections/vec_deque.rs
@@ -1026,7 +1026,10 @@
             iter: Iter {
                 tail: drain_tail,
                 head: drain_head,
-                ring: unsafe { self.buffer_as_mut_slice() },
+                // Crucially, we only create shared references from `self` here and read from
+                // it.  We do not write to `self` nor reborrow to a mutable reference.
+                // Hence the raw pointer we created above, for `deque`, remains valid.
+                ring: unsafe { self.buffer_as_slice() },
             },
         }
     }
diff --git a/src/liballoc/tests/binary_heap.rs b/src/liballoc/tests/binary_heap.rs
index b0d8fa6..536291d 100644
--- a/src/liballoc/tests/binary_heap.rs
+++ b/src/liballoc/tests/binary_heap.rs
@@ -14,7 +14,7 @@
 use std::panic::{self, AssertUnwindSafe};
 use std::sync::atomic::{AtomicUsize, ATOMIC_USIZE_INIT, Ordering};
 
-use rand::{thread_rng, Rng};
+use rand::{thread_rng, seq::SliceRandom};
 
 #[test]
 fn test_iterator() {
@@ -332,7 +332,7 @@
             let panic_item = PanicOrd(i, true);
 
             // heapify the sane items
-            rng.shuffle(&mut panic_ords);
+            panic_ords.shuffle(&mut rng);
             let mut heap = BinaryHeap::from(panic_ords);
             let inner_data;
 
diff --git a/src/liballoc/tests/slice.rs b/src/liballoc/tests/slice.rs
index 787e495..6f31e6c 100644
--- a/src/liballoc/tests/slice.rs
+++ b/src/liballoc/tests/slice.rs
@@ -18,7 +18,7 @@
 use std::sync::atomic::{ATOMIC_USIZE_INIT, AtomicUsize};
 use std::thread;
 
-use rand::{Rng, RngCore, thread_rng};
+use rand::{Rng, RngCore, thread_rng, seq::SliceRandom};
 use rand::distributions::Standard;
 
 fn square(n: usize) -> usize {
@@ -459,7 +459,7 @@
     for i in 0..v.len() {
         v[i] = i as i32;
     }
-    v.sort_by(|_, _| *rng.choose(&[Less, Equal, Greater]).unwrap());
+    v.sort_by(|_, _| *[Less, Equal, Greater].choose(&mut rng).unwrap());
     v.sort();
     for i in 0..v.len() {
         assert_eq!(v[i], i as i32);
diff --git a/src/liballoc/tests/str.rs b/src/liballoc/tests/str.rs
index 683ce2b..9ad8ad1 100644
--- a/src/liballoc/tests/str.rs
+++ b/src/liballoc/tests/str.rs
@@ -1514,9 +1514,9 @@
 
 #[test]
 fn trim_ws() {
-    assert_eq!(" \t  a \t  ".trim_left_matches(|c: char| c.is_whitespace()),
+    assert_eq!(" \t  a \t  ".trim_start_matches(|c: char| c.is_whitespace()),
                     "a \t  ");
-    assert_eq!(" \t  a \t  ".trim_right_matches(|c: char| c.is_whitespace()),
+    assert_eq!(" \t  a \t  ".trim_end_matches(|c: char| c.is_whitespace()),
                " \t  a");
     assert_eq!(" \t  a \t  ".trim_start_matches(|c: char| c.is_whitespace()),
                     "a \t  ");
@@ -1524,9 +1524,9 @@
                " \t  a");
     assert_eq!(" \t  a \t  ".trim_matches(|c: char| c.is_whitespace()),
                     "a");
-    assert_eq!(" \t   \t  ".trim_left_matches(|c: char| c.is_whitespace()),
+    assert_eq!(" \t   \t  ".trim_start_matches(|c: char| c.is_whitespace()),
                          "");
-    assert_eq!(" \t   \t  ".trim_right_matches(|c: char| c.is_whitespace()),
+    assert_eq!(" \t   \t  ".trim_end_matches(|c: char| c.is_whitespace()),
                "");
     assert_eq!(" \t   \t  ".trim_start_matches(|c: char| c.is_whitespace()),
                          "");
diff --git a/src/libcompiler_builtins b/src/libcompiler_builtins
deleted file mode 160000
index 10f4f35..0000000
--- a/src/libcompiler_builtins
+++ /dev/null
@@ -1 +0,0 @@
-Subproject commit 10f4f35f9670bb29715a8c1ec01284852d47ed35
diff --git a/src/libcore/Cargo.toml b/src/libcore/Cargo.toml
index 7fd61f0..fa2ab11 100644
--- a/src/libcore/Cargo.toml
+++ b/src/libcore/Cargo.toml
@@ -20,7 +20,7 @@
 path = "../libcore/benches/lib.rs"
 
 [dev-dependencies]
-rand = "0.5"
+rand = "0.6"
 
 [features]
 # Make panics and failed asserts immediately abort without formatting any message
diff --git a/src/libcore/ffi.rs b/src/libcore/ffi.rs
index d7a112e..899fae9 100644
--- a/src/libcore/ffi.rs
+++ b/src/libcore/ffi.rs
@@ -1,7 +1,6 @@
 #![stable(feature = "", since = "1.30.0")]
 
 #![allow(non_camel_case_types)]
-#![cfg_attr(stage0, allow(dead_code))]
 
 //! Utilities related to FFI bindings.
 
@@ -123,7 +122,6 @@
                      all supported platforms",
            issue = "27745")]
 #[repr(transparent)]
-#[cfg(not(stage0))]
 pub struct VaList<'a>(&'a mut VaListImpl);
 
 // The VaArgSafe trait needs to be used in public interfaces, however, the trait
@@ -173,7 +171,6 @@
            issue = "27745")]
 impl<T> sealed_trait::VaArgSafe for *const T {}
 
-#[cfg(not(stage0))]
 impl<'a> VaList<'a> {
     /// Advance to the next arg.
     #[unstable(feature = "c_variadic",
@@ -208,7 +205,6 @@
     }
 }
 
-#[cfg(not(stage0))]
 extern "rust-intrinsic" {
     /// Destroy the arglist `ap` after initialization with `va_start` or
     /// `va_copy`.
diff --git a/src/libcore/intrinsics.rs b/src/libcore/intrinsics.rs
index eebb98b..b94d5b4 100644
--- a/src/libcore/intrinsics.rs
+++ b/src/libcore/intrinsics.rs
@@ -718,7 +718,6 @@
     pub fn uninit<T>() -> T;
 
     /// Moves a value out of scope without running drop glue.
-    #[cfg(not(stage0))]
     pub fn forget<T: ?Sized>(_: T);
 
     /// Reinterprets the bits of a value of one type as another type.
@@ -1476,14 +1475,12 @@
     /// The stabilized versions of this intrinsic are available on the integer
     /// primitives via the `rotate_left` method. For example,
     /// [`std::u32::rotate_left`](../../std/primitive.u32.html#method.rotate_left)
-    #[cfg(not(stage0))]
     pub fn rotate_left<T>(x: T, y: T) -> T;
 
     /// Performs rotate right.
     /// The stabilized versions of this intrinsic are available on the integer
     /// primitives via the `rotate_right` method. For example,
     /// [`std::u32::rotate_right`](../../std/primitive.u32.html#method.rotate_right)
-    #[cfg(not(stage0))]
     pub fn rotate_right<T>(x: T, y: T) -> T;
 
     /// Returns (a + b) mod 2<sup>N</sup>, where N is the width of T in bits.
diff --git a/src/libcore/marker.rs b/src/libcore/marker.rs
index 0d43f92..d3d1612 100644
--- a/src/libcore/marker.rs
+++ b/src/libcore/marker.rs
@@ -640,15 +640,15 @@
 #[unstable(feature = "pin", issue = "49150")]
 pub auto trait Unpin {}
 
-/// A type which does not implement `Unpin`.
+/// A marker type which does not implement `Unpin`.
 ///
-/// If a type contains a `Pinned`, it will not implement `Unpin` by default.
+/// If a type contains a `PhantomPinned`, it will not implement `Unpin` by default.
 #[unstable(feature = "pin", issue = "49150")]
 #[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
-pub struct Pinned;
+pub struct PhantomPinned;
 
 #[unstable(feature = "pin", issue = "49150")]
-impl !Unpin for Pinned {}
+impl !Unpin for PhantomPinned {}
 
 #[unstable(feature = "pin", issue = "49150")]
 impl<'a, T: ?Sized + 'a> Unpin for &'a T {}
diff --git a/src/libcore/mem.rs b/src/libcore/mem.rs
index 06754f1..afd9fcb 100644
--- a/src/libcore/mem.rs
+++ b/src/libcore/mem.rs
@@ -149,7 +149,6 @@
 ///
 /// [`forget`]: fn.forget.html
 #[inline]
-#[cfg(not(stage0))]
 #[unstable(feature = "forget_unsized", issue = "0")]
 pub fn forget_unsized<T: ?Sized>(t: T) {
     unsafe { intrinsics::forget(t) }
diff --git a/src/libcore/num/mod.rs b/src/libcore/num/mod.rs
index 13b4221..4acf3a1 100644
--- a/src/libcore/num/mod.rs
+++ b/src/libcore/num/mod.rs
@@ -2330,12 +2330,7 @@
             #[rustc_const_unstable(feature = "const_int_rotate")]
             #[inline]
             pub const fn rotate_left(self, n: u32) -> Self {
-                #[cfg(not(stage0))] {
-                    unsafe { intrinsics::rotate_left(self, n as $SelfT) }
-                }
-                #[cfg(stage0)] {
-                    (self << (n % $BITS)) | (self >> (($BITS - (n % $BITS)) % $BITS))
-                }
+                unsafe { intrinsics::rotate_left(self, n as $SelfT) }
             }
         }
 
@@ -2360,12 +2355,7 @@
             #[rustc_const_unstable(feature = "const_int_rotate")]
             #[inline]
             pub const fn rotate_right(self, n: u32) -> Self {
-                #[cfg(not(stage0))] {
-                    unsafe { intrinsics::rotate_right(self, n as $SelfT) }
-                }
-                #[cfg(stage0)] {
-                    (self >> (n % $BITS)) | (self << (($BITS - (n % $BITS)) % $BITS))
-                }
+                unsafe { intrinsics::rotate_right(self, n as $SelfT) }
             }
         }
 
diff --git a/src/libcore/ops/unsize.rs b/src/libcore/ops/unsize.rs
index 4d9a40a..e86a392 100644
--- a/src/libcore/ops/unsize.rs
+++ b/src/libcore/ops/unsize.rs
@@ -93,7 +93,7 @@
 /// {}
 /// ```
 #[unstable(feature = "dispatch_from_dyn", issue = "0")]
-#[cfg_attr(not(stage0), lang = "dispatch_from_dyn")]
+#[lang = "dispatch_from_dyn"]
 pub trait DispatchFromDyn<T> {
     // Empty.
 }
diff --git a/src/libcore/pin.rs b/src/libcore/pin.rs
index aa51555..0ad6e8c 100644
--- a/src/libcore/pin.rs
+++ b/src/libcore/pin.rs
@@ -7,23 +7,33 @@
 //! since moving an object with pointers to itself will invalidate them,
 //! which could cause undefined behavior.
 //!
-//! In order to prevent objects from moving, they must be pinned
-//! by wrapping a pointer to the data in the [`Pin`] type. A pointer wrapped
-//! in a `Pin` is otherwise equivalent to its normal version, e.g., `Pin<Box<T>>`
-//! and `Box<T>` work the same way except that the first is pinning the value
-//! of `T` in place.
+//! By default, all types in Rust are movable. Rust allows passing all types by-value,
+//! and common smart-pointer types such as `Box`, `Rc`, and `&mut` allow replacing and
+//! moving the values they contain. In order to prevent objects from moving, they must
+//! be pinned by wrapping a pointer to the data in the [`Pin`] type.
+//! Doing this prohibits moving the value behind the pointer.
+//! For example, `Pin<Box<T>>` functions much like a regular `Box<T>`,
+//! but doesn't allow moving `T`. The pointer value itself (the `Box`) can still be moved,
+//! but the value behind it cannot.
 //!
-//! First of all, these are pointer types because pinned data mustn't be passed around by value
-//! (that would change its location in memory).
-//! Secondly, since data can be moved out of `&mut` and `Box` with functions such as [`swap`],
-//! which causes their contents to swap places in memory,
-//! we need dedicated types that prohibit such operations.
+//! Since data can be moved out of `&mut` and `Box` with functions such as [`swap`],
+//! changing the location of the underlying data, [`Pin`] prohibits accessing the
+//! underlying pointer type (the `&mut` or `Box`) directly, and provides its own set of
+//! APIs for accessing and using the value. [`Pin`] also guarantees that no other
+//! functions will move the pointed-to value. This allows for the creation of
+//! self-references and other special behaviors that are only possible for unmovable
+//! values.
 //!
-//! However, these restrictions are usually not necessary,
-//! so most types implement the [`Unpin`] auto-trait,
-//! which indicates that the type can be moved out safely.
-//! Doing so removes the limitations of pinning types,
-//! making them the same as their non-pinning counterparts.
+//! However, these restrictions are usually not necessary. Many types are always freely
+//! movable. These types implement the [`Unpin`] auto-trait, which nullifies the affect
+//! of [`Pin`]. For `T: Unpin`, `Pin<Box<T>>` and `Box<T>` function identically, as do
+//! `Pin<&mut T>` and `&mut T`.
+//!
+//! Note that pinning and `Unpin` only affect the pointed-to type. For example, whether
+//! or not `Box<T>` is `Unpin` has no affect on the behavior of `Pin<Box<T>>`. Similarly,
+//! `Pin<Box<T>>` and `Pin<&mut T>` are always `Unpin` themselves, even though the
+//! `T` underneath them isn't, because the pointers in `Pin<Box<_>>` and `Pin<&mut _>`
+//! are always freely movable, even if the data they point to isn't.
 //!
 //! [`Pin`]: struct.Pin.html
 //! [`Unpin`]: trait.Unpin.html
@@ -36,7 +46,7 @@
 //! #![feature(pin)]
 //!
 //! use std::pin::Pin;
-//! use std::marker::Pinned;
+//! use std::marker::PhantomPinned;
 //! use std::ptr::NonNull;
 //!
 //! // This is a self-referential struct since the slice field points to the data field.
@@ -47,7 +57,7 @@
 //! struct Unmovable {
 //!     data: String,
 //!     slice: NonNull<String>,
-//!     _pin: Pinned,
+//!     _pin: PhantomPinned,
 //! }
 //!
 //! impl Unmovable {
@@ -60,7 +70,7 @@
 //!             // we only create the pointer once the data is in place
 //!             // otherwise it will have already moved before we even started
 //!             slice: NonNull::dangling(),
-//!             _pin: Pinned,
+//!             _pin: PhantomPinned,
 //!         };
 //!         let mut boxed = Box::pinned(res);
 //!
diff --git a/src/libcore/ptr.rs b/src/libcore/ptr.rs
index b11ae30..f61e582 100644
--- a/src/libcore/ptr.rs
+++ b/src/libcore/ptr.rs
@@ -2848,14 +2848,14 @@
 #[unstable(feature = "ptr_internals", issue = "0")]
 impl<'a, T: ?Sized> From<&'a mut T> for Unique<T> {
     fn from(reference: &'a mut T) -> Self {
-        Unique { pointer: unsafe { NonZero(reference as _) }, _marker: PhantomData }
+        Unique { pointer: unsafe { NonZero(reference as *mut T) }, _marker: PhantomData }
     }
 }
 
 #[unstable(feature = "ptr_internals", issue = "0")]
 impl<'a, T: ?Sized> From<&'a T> for Unique<T> {
     fn from(reference: &'a T) -> Self {
-        Unique { pointer: unsafe { NonZero(reference as _) }, _marker: PhantomData }
+        Unique { pointer: unsafe { NonZero(reference as *const T) }, _marker: PhantomData }
     }
 }
 
@@ -3058,7 +3058,7 @@
 impl<'a, T: ?Sized> From<&'a mut T> for NonNull<T> {
     #[inline]
     fn from(reference: &'a mut T) -> Self {
-        NonNull { pointer: unsafe { NonZero(reference as _) } }
+        NonNull { pointer: unsafe { NonZero(reference as *mut T) } }
     }
 }
 
@@ -3066,6 +3066,6 @@
 impl<'a, T: ?Sized> From<&'a T> for NonNull<T> {
     #[inline]
     fn from(reference: &'a T) -> Self {
-        NonNull { pointer: unsafe { NonZero(reference as _) } }
+        NonNull { pointer: unsafe { NonZero(reference as *const T) } }
     }
 }
diff --git a/src/libcore/sync/atomic.rs b/src/libcore/sync/atomic.rs
index 27eeb04..060983a 100644
--- a/src/libcore/sync/atomic.rs
+++ b/src/libcore/sync/atomic.rs
@@ -1940,7 +1940,7 @@
     8,
     u64 AtomicU64 ATOMIC_U64_INIT
 }
-#[cfg(all(not(stage0), target_has_atomic = "128"))]
+#[cfg(target_has_atomic = "128")]
 atomic_int! {
     unstable(feature = "integer_atomics", issue = "32976"),
     unstable(feature = "integer_atomics", issue = "32976"),
@@ -1954,7 +1954,7 @@
     16,
     i128 AtomicI128 ATOMIC_I128_INIT
 }
-#[cfg(all(not(stage0), target_has_atomic = "128"))]
+#[cfg(target_has_atomic = "128")]
 atomic_int! {
     unstable(feature = "integer_atomics", issue = "32976"),
     unstable(feature = "integer_atomics", issue = "32976"),
diff --git a/src/libcore/tests/num/flt2dec/random.rs b/src/libcore/tests/num/flt2dec/random.rs
index 95dfcb5..21a7c9f 100644
--- a/src/libcore/tests/num/flt2dec/random.rs
+++ b/src/libcore/tests/num/flt2dec/random.rs
@@ -18,7 +18,8 @@
 use core::num::flt2dec::strategy::grisu::format_shortest_opt;
 use core::num::flt2dec::{decode, DecodableFloat, FullDecoded, Decoded};
 
-use rand::{FromEntropy, XorShiftRng};
+use rand::FromEntropy;
+use rand::rngs::SmallRng;
 use rand::distributions::{Distribution, Uniform};
 
 pub fn decode_finite<T: DecodableFloat>(v: T) -> Decoded {
@@ -71,7 +72,10 @@
 pub fn f32_random_equivalence_test<F, G>(f: F, g: G, k: usize, n: usize)
         where F: FnMut(&Decoded, &mut [u8]) -> Option<(usize, i16)>,
               G: FnMut(&Decoded, &mut [u8]) -> (usize, i16) {
-    let mut rng = XorShiftRng::from_entropy();
+    if cfg!(target_os = "emscripten") {
+        return // using rng pulls in i128 support, which doesn't work
+    }
+    let mut rng = SmallRng::from_entropy();
     let f32_range = Uniform::new(0x0000_0001u32, 0x7f80_0000);
     iterate("f32_random_equivalence_test", k, n, f, g, |_| {
         let x = f32::from_bits(f32_range.sample(&mut rng));
@@ -82,7 +86,10 @@
 pub fn f64_random_equivalence_test<F, G>(f: F, g: G, k: usize, n: usize)
         where F: FnMut(&Decoded, &mut [u8]) -> Option<(usize, i16)>,
               G: FnMut(&Decoded, &mut [u8]) -> (usize, i16) {
-    let mut rng = XorShiftRng::from_entropy();
+    if cfg!(target_os = "emscripten") {
+        return // using rng pulls in i128 support, which doesn't work
+    }
+    let mut rng = SmallRng::from_entropy();
     let f64_range = Uniform::new(0x0000_0000_0000_0001u64, 0x7ff0_0000_0000_0000);
     iterate("f64_random_equivalence_test", k, n, f, g, |_| {
         let x = f64::from_bits(f64_range.sample(&mut rng));
diff --git a/src/libcore/tests/slice.rs b/src/libcore/tests/slice.rs
index dba5a43..4f00ebe 100644
--- a/src/libcore/tests/slice.rs
+++ b/src/libcore/tests/slice.rs
@@ -1024,11 +1024,11 @@
 fn sort_unstable() {
     use core::cmp::Ordering::{Equal, Greater, Less};
     use core::slice::heapsort;
-    use rand::{FromEntropy, Rng, XorShiftRng};
+    use rand::{FromEntropy, Rng, rngs::SmallRng, seq::SliceRandom};
 
     let mut v = [0; 600];
     let mut tmp = [0; 600];
-    let mut rng = XorShiftRng::from_entropy();
+    let mut rng = SmallRng::from_entropy();
 
     for len in (2..25).chain(500..510) {
         let v = &mut v[0..len];
@@ -1073,7 +1073,7 @@
     for i in 0..v.len() {
         v[i] = i as i32;
     }
-    v.sort_unstable_by(|_, _| *rng.choose(&[Less, Equal, Greater]).unwrap());
+    v.sort_unstable_by(|_, _| *[Less, Equal, Greater].choose(&mut rng).unwrap());
     v.sort_unstable();
     for i in 0..v.len() {
         assert_eq!(v[i], i as i32);
diff --git a/src/liblibc b/src/liblibc
deleted file mode 160000
index 5b40375..0000000
--- a/src/liblibc
+++ /dev/null
@@ -1 +0,0 @@
-Subproject commit 5b403753da9ec8ff501adf34cb6d63b319b4a3ae
diff --git a/src/libpanic_abort/Cargo.toml b/src/libpanic_abort/Cargo.toml
index 633d273..e304e61 100644
--- a/src/libpanic_abort/Cargo.toml
+++ b/src/libpanic_abort/Cargo.toml
@@ -11,5 +11,5 @@
 
 [dependencies]
 core = { path = "../libcore" }
-libc = { path = "../rustc/libc_shim" }
-compiler_builtins = { path = "../rustc/compiler_builtins_shim" }
+libc = { version = "0.2", default-features = false }
+compiler_builtins = "0.1.0"
diff --git a/src/libpanic_unwind/Cargo.toml b/src/libpanic_unwind/Cargo.toml
index 74aaa4d..c9fce62 100644
--- a/src/libpanic_unwind/Cargo.toml
+++ b/src/libpanic_unwind/Cargo.toml
@@ -12,6 +12,6 @@
 [dependencies]
 alloc = { path = "../liballoc" }
 core = { path = "../libcore" }
-libc = { path = "../rustc/libc_shim" }
+libc = { version = "0.2", default-features = false }
 unwind = { path = "../libunwind" }
-compiler_builtins = { path = "../rustc/compiler_builtins_shim" }
+compiler_builtins = "0.1.0"
diff --git a/src/libprofiler_builtins/Cargo.toml b/src/libprofiler_builtins/Cargo.toml
index 79192fb..7c95cf0 100644
--- a/src/libprofiler_builtins/Cargo.toml
+++ b/src/libprofiler_builtins/Cargo.toml
@@ -13,7 +13,7 @@
 
 [dependencies]
 core = { path = "../libcore" }
-compiler_builtins = { path = "../rustc/compiler_builtins_shim" }
+compiler_builtins = { version = "0.1.0", features = ['rustc-dep-of-std'] }
 
 [build-dependencies]
 cc = "1.0.1"
diff --git a/src/libprofiler_builtins/build.rs b/src/libprofiler_builtins/build.rs
index 8d6c7d6..db72ce7 100644
--- a/src/libprofiler_builtins/build.rs
+++ b/src/libprofiler_builtins/build.rs
@@ -56,9 +56,15 @@
         cfg.define("COMPILER_RT_HAS_UNAME", Some("1"));
     }
 
+    // The source for `compiler-rt` comes from the `compiler-builtins` crate, so
+    // load our env var set by cargo to find the source code.
+    let root = env::var_os("DEP_COMPILER_RT_COMPILER_RT").unwrap();
+    let root = Path::new(&root);
+
     for src in profile_sources {
-        cfg.file(Path::new("../libcompiler_builtins/compiler-rt/lib/profile").join(src));
+        cfg.file(root.join("lib").join("profile").join(src));
     }
 
+    cfg.warnings(false);
     cfg.compile("profiler-rt");
 }
diff --git a/src/librustc/ich/impls_ty.rs b/src/librustc/ich/impls_ty.rs
index e6a7c20..56da6b7 100644
--- a/src/librustc/ich/impls_ty.rs
+++ b/src/librustc/ich/impls_ty.rs
@@ -338,7 +338,7 @@
 );
 
 impl_stable_hash_for!(
-    impl<'tcx, M> for enum mir::interpret::AllocType<'tcx, M> [ mir::interpret::AllocType ] {
+    impl<'tcx> for enum mir::interpret::AllocKind<'tcx> [ mir::interpret::AllocKind ] {
         Function(instance),
         Static(def_id),
         Memory(mem),
diff --git a/src/librustc/lint/builtin.rs b/src/librustc/lint/builtin.rs
index a09d167..b7759a8 100644
--- a/src/librustc/lint/builtin.rs
+++ b/src/librustc/lint/builtin.rs
@@ -463,7 +463,7 @@
                     Ok(ref s) => {
                         // FIXME(Manishearth) ideally the emitting code
                         // can tell us whether or not this is global
-                        let opt_colon = if s.trim_left().starts_with("::") {
+                        let opt_colon = if s.trim_start().starts_with("::") {
                             ""
                         } else {
                             "::"
diff --git a/src/librustc/mir/interpret/mod.rs b/src/librustc/mir/interpret/mod.rs
index 9369b6e..d54a1c9 100644
--- a/src/librustc/mir/interpret/mod.rs
+++ b/src/librustc/mir/interpret/mod.rs
@@ -41,7 +41,6 @@
 use ty::layout::{self, Size};
 use middle::region;
 use std::io;
-use std::hash::Hash;
 use rustc_serialize::{Encoder, Decodable, Encodable};
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::sync::{Lock as Mutex, HashMapExt};
@@ -90,7 +89,7 @@
 impl ::rustc_serialize::UseSpecializedDecodable for AllocId {}
 
 #[derive(RustcDecodable, RustcEncodable)]
-enum AllocKind {
+enum AllocDiscriminant {
     Alloc,
     Fn,
     Static,
@@ -104,23 +103,23 @@
     tcx: TyCtxt<'a, 'tcx, 'tcx>,
     alloc_id: AllocId,
 ) -> Result<(), E::Error> {
-    let alloc_type: AllocType<'tcx, &'tcx Allocation> =
+    let alloc_kind: AllocKind<'tcx> =
         tcx.alloc_map.lock().get(alloc_id).expect("no value for AllocId");
-    match alloc_type {
-        AllocType::Memory(alloc) => {
+    match alloc_kind {
+        AllocKind::Memory(alloc) => {
             trace!("encoding {:?} with {:#?}", alloc_id, alloc);
-            AllocKind::Alloc.encode(encoder)?;
+            AllocDiscriminant::Alloc.encode(encoder)?;
             alloc.encode(encoder)?;
         }
-        AllocType::Function(fn_instance) => {
+        AllocKind::Function(fn_instance) => {
             trace!("encoding {:?} with {:#?}", alloc_id, fn_instance);
-            AllocKind::Fn.encode(encoder)?;
+            AllocDiscriminant::Fn.encode(encoder)?;
             fn_instance.encode(encoder)?;
         }
-        AllocType::Static(did) => {
+        AllocKind::Static(did) => {
             // referring to statics doesn't need to know about their allocations,
             // just about its DefId
-            AllocKind::Static.encode(encoder)?;
+            AllocDiscriminant::Static.encode(encoder)?;
             did.encode(encoder)?;
         }
     }
@@ -189,10 +188,10 @@
         let idx = decoder.read_u32()? as usize;
         let pos = self.state.data_offsets[idx] as usize;
 
-        // Decode the AllocKind now so that we know if we have to reserve an
+        // Decode the AllocDiscriminant now so that we know if we have to reserve an
         // AllocId.
         let (alloc_kind, pos) = decoder.with_position(pos, |decoder| {
-            let alloc_kind = AllocKind::decode(decoder)?;
+            let alloc_kind = AllocDiscriminant::decode(decoder)?;
             Ok((alloc_kind, decoder.position()))
         })?;
 
@@ -208,7 +207,7 @@
                 ref mut entry @ State::Empty => {
                     // We are allowed to decode
                     match alloc_kind {
-                        AllocKind::Alloc => {
+                        AllocDiscriminant::Alloc => {
                             // If this is an allocation, we need to reserve an
                             // AllocId so we can decode cyclic graphs.
                             let alloc_id = decoder.tcx().alloc_map.lock().reserve();
@@ -217,7 +216,7 @@
                                 alloc_id);
                             Some(alloc_id)
                         },
-                        AllocKind::Fn | AllocKind::Static => {
+                        AllocDiscriminant::Fn | AllocDiscriminant::Static => {
                             // Fns and statics cannot be cyclic and their AllocId
                             // is determined later by interning
                             *entry = State::InProgressNonAlloc(
@@ -251,15 +250,15 @@
         // Now decode the actual data
         let alloc_id = decoder.with_position(pos, |decoder| {
             match alloc_kind {
-                AllocKind::Alloc => {
+                AllocDiscriminant::Alloc => {
                     let allocation = <&'tcx Allocation as Decodable>::decode(decoder)?;
                     // We already have a reserved AllocId.
                     let alloc_id = alloc_id.unwrap();
                     trace!("decoded alloc {:?} {:#?}", alloc_id, allocation);
-                    decoder.tcx().alloc_map.lock().set_id_same_memory(alloc_id, allocation);
+                    decoder.tcx().alloc_map.lock().set_alloc_id_same_memory(alloc_id, allocation);
                     Ok(alloc_id)
                 },
-                AllocKind::Fn => {
+                AllocDiscriminant::Fn => {
                     assert!(alloc_id.is_none());
                     trace!("creating fn alloc id");
                     let instance = ty::Instance::decode(decoder)?;
@@ -267,7 +266,7 @@
                     let alloc_id = decoder.tcx().alloc_map.lock().create_fn_alloc(instance);
                     Ok(alloc_id)
                 },
-                AllocKind::Static => {
+                AllocDiscriminant::Static => {
                     assert!(alloc_id.is_none());
                     trace!("creating extern static alloc id at");
                     let did = DefId::decode(decoder)?;
@@ -292,39 +291,42 @@
 }
 
 #[derive(Debug, Clone, Eq, PartialEq, Hash, RustcDecodable, RustcEncodable)]
-pub enum AllocType<'tcx, M> {
+pub enum AllocKind<'tcx> {
     /// The alloc id is used as a function pointer
     Function(Instance<'tcx>),
     /// The alloc id points to a "lazy" static variable that did not get computed (yet).
     /// This is also used to break the cycle in recursive statics.
     Static(DefId),
     /// The alloc id points to memory
-    Memory(M)
+    Memory(&'tcx Allocation),
 }
 
-pub struct AllocMap<'tcx, M> {
+pub struct AllocMap<'tcx> {
     /// Lets you know what an AllocId refers to
-    id_to_type: FxHashMap<AllocId, AllocType<'tcx, M>>,
+    id_to_kind: FxHashMap<AllocId, AllocKind<'tcx>>,
 
-    /// Used to ensure that functions and statics only get one associated AllocId
-    type_interner: FxHashMap<AllocType<'tcx, M>, AllocId>,
+    /// Used to ensure that statics only get one associated AllocId
+    type_interner: FxHashMap<AllocKind<'tcx>, AllocId>,
 
     /// The AllocId to assign to the next requested id.
     /// Always incremented, never gets smaller.
     next_id: AllocId,
 }
 
-impl<'tcx, M: fmt::Debug + Eq + Hash + Clone> AllocMap<'tcx, M> {
+impl<'tcx> AllocMap<'tcx> {
     pub fn new() -> Self {
         AllocMap {
-            id_to_type: Default::default(),
+            id_to_kind: Default::default(),
             type_interner: Default::default(),
             next_id: AllocId(0),
         }
     }
 
-    /// obtains a new allocation ID that can be referenced but does not
+    /// Obtains a new allocation ID that can be referenced but does not
     /// yet have an allocation backing it.
+    ///
+    /// Make sure to call `set_alloc_id_memory` or `set_alloc_id_same_memory` before returning such
+    /// an `AllocId` from a query.
     pub fn reserve(
         &mut self,
     ) -> AllocId {
@@ -337,53 +339,73 @@
         next
     }
 
-    fn intern(&mut self, alloc_type: AllocType<'tcx, M>) -> AllocId {
-        if let Some(&alloc_id) = self.type_interner.get(&alloc_type) {
+    fn intern(&mut self, alloc_kind: AllocKind<'tcx>) -> AllocId {
+        if let Some(&alloc_id) = self.type_interner.get(&alloc_kind) {
             return alloc_id;
         }
         let id = self.reserve();
-        debug!("creating alloc_type {:?} with id {}", alloc_type, id);
-        self.id_to_type.insert(id, alloc_type.clone());
-        self.type_interner.insert(alloc_type, id);
+        debug!("creating alloc_kind {:?} with id {}", alloc_kind, id);
+        self.id_to_kind.insert(id, alloc_kind.clone());
+        self.type_interner.insert(alloc_kind, id);
         id
     }
 
-    // FIXME: Check if functions have identity. If not, we should not intern these,
-    // but instead create a new id per use.
-    // Alternatively we could just make comparing function pointers an error.
+    /// Functions cannot be identified by pointers, as asm-equal functions can get deduplicated
+    /// by the linker and functions can be duplicated across crates.
+    /// We thus generate a new `AllocId` for every mention of a function. This means that
+    /// `main as fn() == main as fn()` is false, while `let x = main as fn(); x == x` is true.
     pub fn create_fn_alloc(&mut self, instance: Instance<'tcx>) -> AllocId {
-        self.intern(AllocType::Function(instance))
+        let id = self.reserve();
+        self.id_to_kind.insert(id, AllocKind::Function(instance));
+        id
     }
 
-    pub fn get(&self, id: AllocId) -> Option<AllocType<'tcx, M>> {
-        self.id_to_type.get(&id).cloned()
+    /// Returns `None` in case the `AllocId` is dangling. An `EvalContext` can still have a
+    /// local `Allocation` for that `AllocId`, but having such an `AllocId` in a constant is
+    /// illegal and will likely ICE.
+    /// This function exists to allow const eval to detect the difference between evaluation-
+    /// local dangling pointers and allocations in constants/statics.
+    pub fn get(&self, id: AllocId) -> Option<AllocKind<'tcx>> {
+        self.id_to_kind.get(&id).cloned()
     }
 
-    pub fn unwrap_memory(&self, id: AllocId) -> M {
+    /// Panics if the `AllocId` does not refer to an `Allocation`
+    pub fn unwrap_memory(&self, id: AllocId) -> &'tcx Allocation {
         match self.get(id) {
-            Some(AllocType::Memory(mem)) => mem,
+            Some(AllocKind::Memory(mem)) => mem,
             _ => bug!("expected allocation id {} to point to memory", id),
         }
     }
 
+    /// Generate an `AllocId` for a static or return a cached one in case this function has been
+    /// called on the same static before.
     pub fn intern_static(&mut self, static_id: DefId) -> AllocId {
-        self.intern(AllocType::Static(static_id))
+        self.intern(AllocKind::Static(static_id))
     }
 
-    pub fn allocate(&mut self, mem: M) -> AllocId {
+    /// Intern the `Allocation` and return a new `AllocId`, even if there's already an identical
+    /// `Allocation` with a different `AllocId`.
+    // FIXME: is this really necessary? Can we ensure `FOO` and `BAR` being different after codegen
+    // in `static FOO: u32 = 42; static BAR: u32 = 42;` even if they reuse the same allocation
+    // inside rustc?
+    pub fn allocate(&mut self, mem: &'tcx Allocation) -> AllocId {
         let id = self.reserve();
-        self.set_id_memory(id, mem);
+        self.set_alloc_id_memory(id, mem);
         id
     }
 
-    pub fn set_id_memory(&mut self, id: AllocId, mem: M) {
-        if let Some(old) = self.id_to_type.insert(id, AllocType::Memory(mem)) {
+    /// Freeze an `AllocId` created with `reserve` by pointing it at an `Allocation`. Trying to
+    /// call this function twice, even with the same `Allocation` will ICE the compiler.
+    pub fn set_alloc_id_memory(&mut self, id: AllocId, mem: &'tcx Allocation) {
+        if let Some(old) = self.id_to_kind.insert(id, AllocKind::Memory(mem)) {
             bug!("tried to set allocation id {}, but it was already existing as {:#?}", id, old);
         }
     }
 
-    pub fn set_id_same_memory(&mut self, id: AllocId, mem: M) {
-       self.id_to_type.insert_same(id, AllocType::Memory(mem));
+    /// Freeze an `AllocId` created with `reserve` by pointing it at an `Allocation`. May be called
+    /// twice for the same `(AllocId, Allocation)` pair.
+    fn set_alloc_id_same_memory(&mut self, id: AllocId, mem: &'tcx Allocation) {
+        self.id_to_kind.insert_same(id, AllocKind::Memory(mem));
     }
 }
 
diff --git a/src/librustc/mir/interpret/value.rs b/src/librustc/mir/interpret/value.rs
index 500bd47..b8d4c5a 100644
--- a/src/librustc/mir/interpret/value.rs
+++ b/src/librustc/mir/interpret/value.rs
@@ -18,7 +18,7 @@
 /// Represents the result of a raw const operation, pre-validation.
 #[derive(Copy, Clone, Debug, Eq, PartialEq, RustcEncodable, RustcDecodable, Hash)]
 pub struct RawConst<'tcx> {
-    // the value lives here, at offset 0, and that allocation definitely is a `AllocType::Memory`
+    // the value lives here, at offset 0, and that allocation definitely is a `AllocKind::Memory`
     // (so you can use `AllocMap::unwrap_memory`).
     pub alloc_id: AllocId,
     pub ty: Ty<'tcx>,
diff --git a/src/librustc/mir/mod.rs b/src/librustc/mir/mod.rs
index b7a4295..68b5c3e 100644
--- a/src/librustc/mir/mod.rs
+++ b/src/librustc/mir/mod.rs
@@ -2637,7 +2637,7 @@
                 if let Ref(_, &ty::TyS { sty: Str, .. }, _) = ty.sty {
                     return ty::tls::with(|tcx| {
                         let alloc = tcx.alloc_map.lock().get(ptr.alloc_id);
-                        if let Some(interpret::AllocType::Memory(alloc)) = alloc {
+                        if let Some(interpret::AllocKind::Memory(alloc)) = alloc {
                             assert_eq!(len as usize as u128, len);
                             let slice =
                                 &alloc.bytes[(ptr.offset.bytes() as usize)..][..(len as usize)];
diff --git a/src/librustc/session/config.rs b/src/librustc/session/config.rs
index 750b7f1..b58d80e 100644
--- a/src/librustc/session/config.rs
+++ b/src/librustc/session/config.rs
@@ -14,7 +14,7 @@
 use std::str::FromStr;
 
 use session::{early_error, early_warn, Session};
-use session::search_paths::SearchPaths;
+use session::search_paths::SearchPath;
 
 use rustc_target::spec::{LinkerFlavor, PanicStrategy, RelroLevel};
 use rustc_target::spec::{Target, TargetTriple};
@@ -374,7 +374,7 @@
         lint_cap: Option<lint::Level> [TRACKED],
         describe_lints: bool [UNTRACKED],
         output_types: OutputTypes [TRACKED],
-        search_paths: SearchPaths [UNTRACKED],
+        search_paths: Vec<SearchPath> [UNTRACKED],
         libs: Vec<(String, Option<String>, Option<cstore::NativeLibraryKind>)> [TRACKED],
         maybe_sysroot: Option<PathBuf> [TRACKED],
 
@@ -593,7 +593,7 @@
             lint_cap: None,
             describe_lints: false,
             output_types: OutputTypes(BTreeMap::new()),
-            search_paths: SearchPaths::new(),
+            search_paths: vec![],
             maybe_sysroot: None,
             target_triple: TargetTriple::from_triple(host_triple()),
             test: false,
@@ -1135,6 +1135,8 @@
         "enable incremental compilation"),
     default_linker_libraries: Option<bool> = (None, parse_opt_bool, [UNTRACKED],
         "allow the linker to link its default libraries"),
+    linker_flavor: Option<LinkerFlavor> = (None, parse_linker_flavor, [UNTRACKED],
+                                           "Linker flavor"),
 }
 
 options! {DebuggingOptions, DebuggingSetter, basic_debugging_options,
@@ -1297,8 +1299,6 @@
         "pass `-install_name @rpath/...` to the macOS linker"),
     sanitizer: Option<Sanitizer> = (None, parse_sanitizer, [TRACKED],
                                     "Use a sanitizer"),
-    linker_flavor: Option<LinkerFlavor> = (None, parse_linker_flavor, [UNTRACKED],
-                                           "Linker flavor"),
     fuel: Option<(String, u64)> = (None, parse_optimization_fuel, [TRACKED],
         "set the optimization fuel quota for a crate"),
     print_fuel: Option<String> = (None, parse_opt_string, [TRACKED],
@@ -2115,9 +2115,9 @@
         }
     };
 
-    let mut search_paths = SearchPaths::new();
+    let mut search_paths = vec![];
     for s in &matches.opt_strs("L") {
-        search_paths.add_path(&s[..], error_format);
+        search_paths.push(SearchPath::from_cli_opt(&s[..], error_format));
     }
 
     let libs = matches
@@ -2535,6 +2535,7 @@
     use session::config::{build_configuration, build_session_options_and_crate_config};
     use session::config::{LtoCli, CrossLangLto};
     use session::build_session;
+    use session::search_paths::SearchPath;
     use std::collections::{BTreeMap, BTreeSet};
     use std::iter::FromIterator;
     use std::path::PathBuf;
@@ -2790,48 +2791,48 @@
 
         // Reference
         v1.search_paths
-            .add_path("native=abc", super::ErrorOutputType::Json(false));
+            .push(SearchPath::from_cli_opt("native=abc", super::ErrorOutputType::Json(false)));
         v1.search_paths
-            .add_path("crate=def", super::ErrorOutputType::Json(false));
+            .push(SearchPath::from_cli_opt("crate=def", super::ErrorOutputType::Json(false)));
         v1.search_paths
-            .add_path("dependency=ghi", super::ErrorOutputType::Json(false));
+            .push(SearchPath::from_cli_opt("dependency=ghi", super::ErrorOutputType::Json(false)));
         v1.search_paths
-            .add_path("framework=jkl", super::ErrorOutputType::Json(false));
+            .push(SearchPath::from_cli_opt("framework=jkl", super::ErrorOutputType::Json(false)));
         v1.search_paths
-            .add_path("all=mno", super::ErrorOutputType::Json(false));
+            .push(SearchPath::from_cli_opt("all=mno", super::ErrorOutputType::Json(false)));
 
         v2.search_paths
-            .add_path("native=abc", super::ErrorOutputType::Json(false));
+            .push(SearchPath::from_cli_opt("native=abc", super::ErrorOutputType::Json(false)));
         v2.search_paths
-            .add_path("dependency=ghi", super::ErrorOutputType::Json(false));
+            .push(SearchPath::from_cli_opt("dependency=ghi", super::ErrorOutputType::Json(false)));
         v2.search_paths
-            .add_path("crate=def", super::ErrorOutputType::Json(false));
+            .push(SearchPath::from_cli_opt("crate=def", super::ErrorOutputType::Json(false)));
         v2.search_paths
-            .add_path("framework=jkl", super::ErrorOutputType::Json(false));
+            .push(SearchPath::from_cli_opt("framework=jkl", super::ErrorOutputType::Json(false)));
         v2.search_paths
-            .add_path("all=mno", super::ErrorOutputType::Json(false));
+            .push(SearchPath::from_cli_opt("all=mno", super::ErrorOutputType::Json(false)));
 
         v3.search_paths
-            .add_path("crate=def", super::ErrorOutputType::Json(false));
+            .push(SearchPath::from_cli_opt("crate=def", super::ErrorOutputType::Json(false)));
         v3.search_paths
-            .add_path("framework=jkl", super::ErrorOutputType::Json(false));
+            .push(SearchPath::from_cli_opt("framework=jkl", super::ErrorOutputType::Json(false)));
         v3.search_paths
-            .add_path("native=abc", super::ErrorOutputType::Json(false));
+            .push(SearchPath::from_cli_opt("native=abc", super::ErrorOutputType::Json(false)));
         v3.search_paths
-            .add_path("dependency=ghi", super::ErrorOutputType::Json(false));
+            .push(SearchPath::from_cli_opt("dependency=ghi", super::ErrorOutputType::Json(false)));
         v3.search_paths
-            .add_path("all=mno", super::ErrorOutputType::Json(false));
+            .push(SearchPath::from_cli_opt("all=mno", super::ErrorOutputType::Json(false)));
 
         v4.search_paths
-            .add_path("all=mno", super::ErrorOutputType::Json(false));
+            .push(SearchPath::from_cli_opt("all=mno", super::ErrorOutputType::Json(false)));
         v4.search_paths
-            .add_path("native=abc", super::ErrorOutputType::Json(false));
+            .push(SearchPath::from_cli_opt("native=abc", super::ErrorOutputType::Json(false)));
         v4.search_paths
-            .add_path("crate=def", super::ErrorOutputType::Json(false));
+            .push(SearchPath::from_cli_opt("crate=def", super::ErrorOutputType::Json(false)));
         v4.search_paths
-            .add_path("dependency=ghi", super::ErrorOutputType::Json(false));
+            .push(SearchPath::from_cli_opt("dependency=ghi", super::ErrorOutputType::Json(false)));
         v4.search_paths
-            .add_path("framework=jkl", super::ErrorOutputType::Json(false));
+            .push(SearchPath::from_cli_opt("framework=jkl", super::ErrorOutputType::Json(false)));
 
         assert!(v1.dep_tracking_hash() == v2.dep_tracking_hash());
         assert!(v1.dep_tracking_hash() == v3.dep_tracking_hash());
diff --git a/src/librustc/session/filesearch.rs b/src/librustc/session/filesearch.rs
index 8159c65..c204556 100644
--- a/src/librustc/session/filesearch.rs
+++ b/src/librustc/session/filesearch.rs
@@ -12,13 +12,12 @@
 
 pub use self::FileMatch::*;
 
-use rustc_data_structures::fx::FxHashSet;
 use std::borrow::Cow;
 use std::env;
 use std::fs;
 use std::path::{Path, PathBuf};
 
-use session::search_paths::{SearchPaths, PathKind};
+use session::search_paths::{SearchPath, PathKind};
 use rustc_fs_util::fix_windows_verbatim_for_gcc;
 
 #[derive(Copy, Clone)]
@@ -30,31 +29,19 @@
 // A module for searching for libraries
 
 pub struct FileSearch<'a> {
-    pub sysroot: &'a Path,
-    pub search_paths: &'a SearchPaths,
-    pub triple: &'a str,
-    pub kind: PathKind,
+    sysroot: &'a Path,
+    triple: &'a str,
+    search_paths: &'a [SearchPath],
+    tlib_path: &'a SearchPath,
+    kind: PathKind,
 }
 
 impl<'a> FileSearch<'a> {
-    pub fn for_each_lib_search_path<F>(&self, mut f: F) where
-        F: FnMut(&Path, PathKind)
-    {
-        let mut visited_dirs = FxHashSet::default();
-        visited_dirs.reserve(self.search_paths.paths.len() + 1);
-        for (path, kind) in self.search_paths.iter(self.kind) {
-            f(path, kind);
-            visited_dirs.insert(path.to_path_buf());
-        }
-
-        debug!("filesearch: searching lib path");
-        let tlib_path = make_target_lib_path(self.sysroot,
-                                             self.triple);
-        if !visited_dirs.contains(&tlib_path) {
-            f(&tlib_path, PathKind::All);
-        }
-
-        visited_dirs.insert(tlib_path);
+    pub fn search_paths(&self) -> impl Iterator<Item = &'a SearchPath> {
+        let kind = self.kind;
+        self.search_paths.iter()
+            .filter(move |sp| sp.kind.matches(kind))
+            .chain(std::iter::once(self.tlib_path))
     }
 
     pub fn get_lib_path(&self) -> PathBuf {
@@ -64,14 +51,8 @@
     pub fn search<F>(&self, mut pick: F)
         where F: FnMut(&Path, PathKind) -> FileMatch
     {
-        self.for_each_lib_search_path(|lib_search_path, kind| {
-            debug!("searching {}", lib_search_path.display());
-            let files = match fs::read_dir(lib_search_path) {
-                Ok(files) => files,
-                Err(..) => return,
-            };
-            let files = files.filter_map(|p| p.ok().map(|s| s.path()))
-                             .collect::<Vec<_>>();
+        for search_path in self.search_paths() {
+            debug!("searching {}", search_path.dir.display());
             fn is_rlib(p: &Path) -> bool {
                 p.extension() == Some("rlib".as_ref())
             }
@@ -79,11 +60,11 @@
             // an rlib and a dylib we only read one of the files of
             // metadata, so in the name of speed, bring all rlib files to
             // the front of the search list.
-            let files1 = files.iter().filter(|p| is_rlib(p));
-            let files2 = files.iter().filter(|p| !is_rlib(p));
+            let files1 = search_path.files.iter().filter(|p| is_rlib(p));
+            let files2 = search_path.files.iter().filter(|p| !is_rlib(p));
             for path in files1.chain(files2) {
                 debug!("testing {}", path.display());
-                let maybe_picked = pick(path, kind);
+                let maybe_picked = pick(path, search_path.kind);
                 match maybe_picked {
                     FileMatches => {
                         debug!("picked {}", path.display());
@@ -93,29 +74,30 @@
                     }
                 }
             }
-        });
+        }
     }
 
     pub fn new(sysroot: &'a Path,
                triple: &'a str,
-               search_paths: &'a SearchPaths,
-               kind: PathKind) -> FileSearch<'a> {
+               search_paths: &'a Vec<SearchPath>,
+               tlib_path: &'a SearchPath,
+               kind: PathKind)
+               -> FileSearch<'a> {
         debug!("using sysroot = {}, triple = {}", sysroot.display(), triple);
         FileSearch {
             sysroot,
-            search_paths,
             triple,
+            search_paths,
+            tlib_path,
             kind,
         }
     }
 
-    // Returns a list of directories where target-specific dylibs might be located.
-    pub fn get_dylib_search_paths(&self) -> Vec<PathBuf> {
-        let mut paths = Vec::new();
-        self.for_each_lib_search_path(|lib_search_path, _| {
-            paths.push(lib_search_path.to_path_buf());
-        });
-        paths
+    // Returns just the directories within the search paths.
+    pub fn search_path_dirs(&self) -> Vec<PathBuf> {
+        self.search_paths()
+            .map(|sp| sp.dir.to_path_buf())
+            .collect()
     }
 
     // Returns a list of directories where target-specific tool binaries are located.
@@ -138,8 +120,7 @@
     p
 }
 
-fn make_target_lib_path(sysroot: &Path,
-                        target_triple: &str) -> PathBuf {
+pub fn make_target_lib_path(sysroot: &Path, target_triple: &str) -> PathBuf {
     sysroot.join(&relative_target_lib_path(sysroot, target_triple))
 }
 
diff --git a/src/librustc/session/mod.rs b/src/librustc/session/mod.rs
index d1dd745..12b5646 100644
--- a/src/librustc/session/mod.rs
+++ b/src/librustc/session/mod.rs
@@ -19,8 +19,8 @@
 use lint::builtin::BuiltinLintDiagnostics;
 use middle::allocator::AllocatorKind;
 use middle::dependency_format;
-use session::search_paths::PathKind;
 use session::config::{OutputType, Lto};
+use session::search_paths::{PathKind, SearchPath};
 use util::nodemap::{FxHashMap, FxHashSet};
 use util::common::{duration_to_secs_str, ErrorReported};
 use util::common::ProfileQueriesMsg;
@@ -48,7 +48,7 @@
 use std::env;
 use std::fmt;
 use std::io::Write;
-use std::path::{Path, PathBuf};
+use std::path::PathBuf;
 use std::time::Duration;
 use std::sync::mpsc;
 use std::sync::atomic::{AtomicUsize, Ordering};
@@ -64,12 +64,15 @@
     pub target: config::Config,
     pub host: Target,
     pub opts: config::Options,
+    pub host_tlib_path: SearchPath,
+    /// This is `None` if the host and target are the same.
+    pub target_tlib_path: Option<SearchPath>,
     pub parse_sess: ParseSess,
     /// For a library crate, this is always none
     pub entry_fn: Once<Option<(NodeId, Span, config::EntryFnType)>>,
     pub plugin_registrar_fn: Once<Option<ast::NodeId>>,
     pub proc_macro_decls_static: Once<Option<ast::NodeId>>,
-    pub default_sysroot: Option<PathBuf>,
+    pub sysroot: PathBuf,
     /// The name of the root source file of the crate, in the local file system.
     /// `None` means that there is no source file.
     pub local_crate_source_file: Option<PathBuf>,
@@ -694,27 +697,22 @@
         )
     }
 
-    pub fn sysroot<'a>(&'a self) -> &'a Path {
-        match self.opts.maybe_sysroot {
-            Some(ref sysroot) => sysroot,
-            None => self.default_sysroot
-                        .as_ref()
-                        .expect("missing sysroot and default_sysroot in Session"),
-        }
-    }
     pub fn target_filesearch(&self, kind: PathKind) -> filesearch::FileSearch<'_> {
         filesearch::FileSearch::new(
-            self.sysroot(),
+            &self.sysroot,
             self.opts.target_triple.triple(),
             &self.opts.search_paths,
+            // target_tlib_path==None means it's the same as host_tlib_path.
+            self.target_tlib_path.as_ref().unwrap_or(&self.host_tlib_path),
             kind,
         )
     }
     pub fn host_filesearch(&self, kind: PathKind) -> filesearch::FileSearch<'_> {
         filesearch::FileSearch::new(
-            self.sysroot(),
+            &self.sysroot,
             config::host_triple(),
             &self.opts.search_paths,
+            &self.host_tlib_path,
             kind,
         )
     }
@@ -1109,9 +1107,18 @@
     let target_cfg = config::build_target_config(&sopts, &span_diagnostic);
 
     let p_s = parse::ParseSess::with_span_handler(span_diagnostic, source_map);
-    let default_sysroot = match sopts.maybe_sysroot {
-        Some(_) => None,
-        None => Some(filesearch::get_or_default_sysroot()),
+    let sysroot = match &sopts.maybe_sysroot {
+        Some(sysroot) => sysroot.clone(),
+        None => filesearch::get_or_default_sysroot(),
+    };
+
+    let host_triple = config::host_triple();
+    let target_triple = sopts.target_triple.triple();
+    let host_tlib_path = SearchPath::from_sysroot_and_triple(&sysroot, host_triple);
+    let target_tlib_path = if host_triple == target_triple {
+        None
+    } else {
+        Some(SearchPath::from_sysroot_and_triple(&sysroot, target_triple))
     };
 
     let file_path_mapping = sopts.file_path_mapping();
@@ -1142,12 +1149,14 @@
         target: target_cfg,
         host,
         opts: sopts,
+        host_tlib_path,
+        target_tlib_path,
         parse_sess: p_s,
         // For a library crate, this is always none
         entry_fn: Once::new(),
         plugin_registrar_fn: Once::new(),
         proc_macro_decls_static: Once::new(),
-        default_sysroot,
+        sysroot,
         local_crate_source_file,
         working_dir,
         lint_store: RwLock::new(lint::LintStore::new()),
diff --git a/src/librustc/session/search_paths.rs b/src/librustc/session/search_paths.rs
index 6b0a8a0..5c44a07 100644
--- a/src/librustc/session/search_paths.rs
+++ b/src/librustc/session/search_paths.rs
@@ -8,18 +8,15 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-use std::slice;
 use std::path::{Path, PathBuf};
 use session::{early_error, config};
+use session::filesearch::make_target_lib_path;
 
 #[derive(Clone, Debug)]
-pub struct SearchPaths {
-    crate paths: Vec<(PathKind, PathBuf)>,
-}
-
-pub struct Iter<'a> {
-    kind: PathKind,
-    iter: slice::Iter<'a, (PathKind, PathBuf)>,
+pub struct SearchPath {
+    pub kind: PathKind,
+    pub dir: PathBuf,
+    pub files: Vec<PathBuf>,
 }
 
 #[derive(Eq, PartialEq, Clone, Copy, Debug, PartialOrd, Ord, Hash)]
@@ -32,12 +29,17 @@
     All,
 }
 
-impl SearchPaths {
-    pub fn new() -> SearchPaths {
-        SearchPaths { paths: Vec::new() }
+impl PathKind {
+    pub fn matches(&self, kind: PathKind) -> bool {
+        match (self, kind) {
+            (PathKind::All, _) | (_, PathKind::All) => true,
+            _ => *self == kind,
+        }
     }
+}
 
-    pub fn add_path(&mut self, path: &str, output: config::ErrorOutputType) {
+impl SearchPath {
+    pub fn from_cli_opt(path: &str, output: config::ErrorOutputType) -> Self {
         let (kind, path) = if path.starts_with("native=") {
             (PathKind::Native, &path["native=".len()..])
         } else if path.starts_with("crate=") {
@@ -54,34 +56,28 @@
         if path.is_empty() {
             early_error(output, "empty search path given via `-L`");
         }
-        self.paths.push((kind, PathBuf::from(path)));
+
+        let dir = PathBuf::from(path);
+        Self::new(kind, dir)
     }
 
-    pub fn iter(&self, kind: PathKind) -> Iter<'_> {
-        Iter { kind: kind, iter: self.paths.iter() }
+    pub fn from_sysroot_and_triple(sysroot: &Path, triple: &str) -> Self {
+        Self::new(PathKind::All, make_target_lib_path(sysroot, triple))
     }
-}
 
-impl<'a> Iterator for Iter<'a> {
-    type Item = (&'a Path, PathKind);
-
-    fn next(&mut self) -> Option<(&'a Path, PathKind)> {
-        loop {
-            match *self.iter.next()? {
-                (kind, ref p) if self.kind == PathKind::All ||
-                                  kind == PathKind::All ||
-                                  kind == self.kind => {
-                    return Some((p, kind))
-                }
-                _ => {}
+    fn new(kind: PathKind, dir: PathBuf) -> Self {
+        // Get the files within the directory.
+        let files = match std::fs::read_dir(&dir) {
+            Ok(files) => {
+                files.filter_map(|p| {
+                    p.ok().map(|s| s.path())
+                })
+                .collect::<Vec<_>>()
             }
-        }
-    }
+            Err(..) => vec![],
+        };
 
-    fn size_hint(&self) -> (usize, Option<usize>) {
-        // This iterator will never return more elements than the base iterator;
-        // but it can ignore all the remaining elements.
-        let (_, upper) = self.iter.size_hint();
-        (0, upper)
+        SearchPath { kind, dir, files }
     }
 }
+
diff --git a/src/librustc/traits/specialize/specialization_graph.rs b/src/librustc/traits/specialize/specialization_graph.rs
index 22221e0..b0ca2f6 100644
--- a/src/librustc/traits/specialize/specialization_graph.rs
+++ b/src/librustc/traits/specialize/specialization_graph.rs
@@ -132,10 +132,12 @@
             simplified_self,
         );
 
-        for possible_sibling in match simplified_self {
-            Some(sty) => self.filtered(sty),
-            None => self.iter(),
-        } {
+        let possible_siblings = match simplified_self {
+            Some(sty) => PotentialSiblings::Filtered(self.filtered(sty)),
+            None => PotentialSiblings::Unfiltered(self.iter()),
+        };
+
+        for possible_sibling in possible_siblings {
             debug!(
                 "insert: impl_def_id={:?}, simplified_self={:?}, possible_sibling={:?}",
                 impl_def_id,
@@ -222,14 +224,37 @@
         Ok(Inserted::BecameNewSibling(last_lint))
     }
 
-    fn iter(&mut self) -> Box<dyn Iterator<Item = DefId> + '_> {
+    fn iter(&mut self) -> impl Iterator<Item = DefId> + '_ {
         let nonblanket = self.nonblanket_impls.iter_mut().flat_map(|(_, v)| v.iter());
-        Box::new(self.blanket_impls.iter().chain(nonblanket).cloned())
+        self.blanket_impls.iter().chain(nonblanket).cloned()
     }
 
-    fn filtered(&mut self, sty: SimplifiedType) -> Box<dyn Iterator<Item = DefId> + '_> {
+    fn filtered(&mut self, sty: SimplifiedType) -> impl Iterator<Item = DefId> + '_ {
         let nonblanket = self.nonblanket_impls.entry(sty).or_default().iter();
-        Box::new(self.blanket_impls.iter().chain(nonblanket).cloned())
+        self.blanket_impls.iter().chain(nonblanket).cloned()
+    }
+}
+
+// A custom iterator used by Children::insert
+enum PotentialSiblings<I, J>
+    where I: Iterator<Item = DefId>,
+          J: Iterator<Item = DefId>
+{
+    Unfiltered(I),
+    Filtered(J)
+}
+
+impl<I, J> Iterator for PotentialSiblings<I, J>
+    where I: Iterator<Item = DefId>,
+          J: Iterator<Item = DefId>
+{
+    type Item = DefId;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        match *self {
+            PotentialSiblings::Unfiltered(ref mut iter) => iter.next(),
+            PotentialSiblings::Filtered(ref mut iter) => iter.next()
+        }
     }
 }
 
diff --git a/src/librustc/ty/context.rs b/src/librustc/ty/context.rs
index a3db3a0..e27d734 100644
--- a/src/librustc/ty/context.rs
+++ b/src/librustc/ty/context.rs
@@ -946,7 +946,7 @@
     /// Stores the value of constants (and deduplicates the actual memory)
     allocation_interner: Lock<FxHashMap<&'tcx Allocation, ()>>,
 
-    pub alloc_map: Lock<interpret::AllocMap<'tcx, &'tcx Allocation>>,
+    pub alloc_map: Lock<interpret::AllocMap<'tcx>>,
 
     layout_interner: Lock<FxHashMap<&'tcx LayoutDetails, ()>>,
 
diff --git a/src/librustc/util/profiling.rs b/src/librustc/util/profiling.rs
index 1e648c4..c2bfa62 100644
--- a/src/librustc/util/profiling.rs
+++ b/src/librustc/util/profiling.rs
@@ -62,11 +62,15 @@
             }
 
             fn print(&self, lock: &mut StderrLock<'_>) {
-                writeln!(lock, "| Phase            | Time (ms)      | Queries        | Hits (%) |")
+                writeln!(lock, "| Phase            | Time (ms)      \
+                                | Time (%) | Queries        | Hits (%)")
                     .unwrap();
-                writeln!(lock, "| ---------------- | -------------- | -------------- | -------- |")
+                writeln!(lock, "| ---------------- | -------------- \
+                                | -------- | -------------- | --------")
                     .unwrap();
 
+                let total_time = ($(self.times.$name + )* 0) as f32;
+
                 $(
                     let (hits, total) = self.query_counts.$name;
                     let (hits, total) = if total > 0 {
@@ -78,11 +82,12 @@
 
                     writeln!(
                         lock,
-                        "| {0: <16} | {1: <14} | {2: <14} | {3: <8} |",
+                        "| {0: <16} | {1: <14} | {2: <8.2} | {3: <14} | {4: <8}",
                         stringify!($name),
                         self.times.$name / 1_000_000,
+                        ((self.times.$name as f32) / total_time) * 100.0,
                         total,
-                        hits
+                        hits,
                     ).unwrap();
                 )*
             }
diff --git a/src/librustc_asan/Cargo.toml b/src/librustc_asan/Cargo.toml
index 734564c..836caf2 100644
--- a/src/librustc_asan/Cargo.toml
+++ b/src/librustc_asan/Cargo.toml
@@ -16,4 +16,4 @@
 [dependencies]
 alloc = { path = "../liballoc" }
 core = { path = "../libcore" }
-compiler_builtins = { path = "../rustc/compiler_builtins_shim" }
+compiler_builtins = "0.1.0"
diff --git a/src/librustc_codegen_llvm/attributes.rs b/src/librustc_codegen_llvm/attributes.rs
index ffe5e12..48e0a3a 100644
--- a/src/librustc_codegen_llvm/attributes.rs
+++ b/src/librustc_codegen_llvm/attributes.rs
@@ -15,14 +15,16 @@
 use rustc::hir::def_id::{DefId, LOCAL_CRATE};
 use rustc::session::Session;
 use rustc::session::config::Sanitizer;
-use rustc::ty::TyCtxt;
+use rustc::ty::{self, TyCtxt, PolyFnSig};
 use rustc::ty::layout::HasTyCtxt;
 use rustc::ty::query::Providers;
+use rustc_data_structures::small_c_str::SmallCStr;
 use rustc_data_structures::sync::Lrc;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_target::spec::PanicStrategy;
 use rustc_codegen_ssa::traits::*;
 
+use abi::Abi;
 use attributes;
 use llvm::{self, Attribute};
 use llvm::AttributePlace::Function;
@@ -60,7 +62,7 @@
 
 /// Tell LLVM whether the function can or cannot unwind.
 #[inline]
-pub fn unwind(val: &'ll Value, can_unwind: bool) {
+fn unwind(val: &'ll Value, can_unwind: bool) {
     Attribute::NoUnwind.toggle_llfn(Function, val, !can_unwind);
 }
 
@@ -129,8 +131,7 @@
 }
 
 pub fn apply_target_cpu_attr(cx: &CodegenCx<'ll, '_>, llfn: &'ll Value) {
-    let cpu = llvm_util::target_cpu(cx.tcx.sess);
-    let target_cpu = CString::new(cpu).unwrap();
+    let target_cpu = SmallCStr::new(llvm_util::target_cpu(cx.tcx.sess));
     llvm::AddFunctionAttrStringValue(
             llfn,
             llvm::AttributePlace::Function,
@@ -150,9 +151,10 @@
 /// Composite function which sets LLVM attributes for function depending on its AST (`#[attribute]`)
 /// attributes.
 pub fn from_fn_attrs(
-    cx: &CodegenCx<'ll, '_>,
+    cx: &CodegenCx<'ll, 'tcx>,
     llfn: &'ll Value,
     id: Option<DefId>,
+    sig: PolyFnSig<'tcx>,
 ) {
     let codegen_fn_attrs = id.map(|id| cx.tcx.codegen_fn_attrs(id))
         .unwrap_or_else(|| CodegenFnAttrs::new());
@@ -194,37 +196,42 @@
             llvm::AttributePlace::ReturnValue, llfn);
     }
 
-    let can_unwind = if codegen_fn_attrs.flags.contains(CodegenFnAttrFlags::UNWIND) {
-        Some(true)
+    unwind(llfn, if cx.tcx.sess.panic_strategy() != PanicStrategy::Unwind {
+        // In panic=abort mode we assume nothing can unwind anywhere, so
+        // optimize based on this!
+        false
+    } else if codegen_fn_attrs.flags.contains(CodegenFnAttrFlags::UNWIND) {
+        // If a specific #[unwind] attribute is present, use that
+        true
     } else if codegen_fn_attrs.flags.contains(CodegenFnAttrFlags::RUSTC_ALLOCATOR_NOUNWIND) {
-        Some(false)
-
-    // Perhaps questionable, but we assume that anything defined
-    // *in Rust code* may unwind. Foreign items like `extern "C" {
-    // fn foo(); }` are assumed not to unwind **unless** they have
-    // a `#[unwind]` attribute.
-    } else if id.map(|id| !cx.tcx.is_foreign_item(id)).unwrap_or(false) {
-        Some(true)
-    } else {
-        None
-    };
-
-    match can_unwind {
-        Some(false) => attributes::unwind(llfn, false),
-        Some(true) if cx.tcx.sess.panic_strategy() == PanicStrategy::Unwind => {
-            attributes::unwind(llfn, true);
+        // Special attribute for allocator functions, which can't unwind
+        false
+    } else if let Some(id) = id {
+        let sig = cx.tcx.normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), &sig);
+        if cx.tcx.is_foreign_item(id) {
+            // Foreign items like `extern "C" { fn foo(); }` are assumed not to
+            // unwind
+            false
+        } else if sig.abi != Abi::Rust && sig.abi != Abi::RustCall {
+            // Any items defined in Rust that *don't* have the `extern` ABI are
+            // defined to not unwind. We insert shims to abort if an unwind
+            // happens to enforce this.
+            false
+        } else {
+            // Anything else defined in Rust is assumed that it can possibly
+            // unwind
+            true
         }
-        Some(true) | None => {}
-    }
+    } else {
+        // assume this can possibly unwind, avoiding the application of a
+        // `nounwind` attribute below.
+        true
+    });
 
     // Always annotate functions with the target-cpu they are compiled for.
     // Without this, ThinLTO won't inline Rust functions into Clang generated
     // functions (because Clang annotates functions this way too).
-    // NOTE: For now we just apply this if -Zcross-lang-lto is specified, since
-    //       it introduce a little overhead and isn't really necessary otherwise.
-    if cx.tcx.sess.opts.debugging_opts.cross_lang_lto.enabled() {
-        apply_target_cpu_attr(cx, llfn);
-    }
+    apply_target_cpu_attr(cx, llfn);
 
     let features = llvm_target_features(cx.tcx.sess)
         .map(|s| s.to_string())
diff --git a/src/librustc_codegen_llvm/back/link.rs b/src/librustc_codegen_llvm/back/link.rs
index 9e100a1..f1c0464 100644
--- a/src/librustc_codegen_llvm/back/link.rs
+++ b/src/librustc_codegen_llvm/back/link.rs
@@ -212,12 +212,7 @@
 }
 
 fn archive_search_paths(sess: &Session) -> Vec<PathBuf> {
-    let mut search = Vec::new();
-    sess.target_filesearch(PathKind::Native).for_each_lib_search_path(|path, _| {
-        search.push(path.to_path_buf());
-    });
-
-    search
+    sess.target_filesearch(PathKind::Native).search_path_dirs()
 }
 
 fn archive_config<'a>(sess: &'a Session,
@@ -1024,11 +1019,10 @@
     // where extern libraries might live, based on the
     // addl_lib_search_paths
     if sess.opts.cg.rpath {
-        let sysroot = sess.sysroot();
         let target_triple = sess.opts.target_triple.triple();
         let mut get_install_prefix_lib_path = || {
             let install_prefix = option_env!("CFG_PREFIX").expect("CFG_PREFIX");
-            let tlib = filesearch::relative_target_lib_path(sysroot, target_triple);
+            let tlib = filesearch::relative_target_lib_path(&sess.sysroot, target_triple);
             let mut path = PathBuf::from(install_prefix);
             path.push(&tlib);
 
@@ -1068,12 +1062,13 @@
 fn add_local_native_libraries(cmd: &mut dyn Linker,
                               sess: &Session,
                               codegen_results: &CodegenResults) {
-    sess.target_filesearch(PathKind::All).for_each_lib_search_path(|path, k| {
-        match k {
-            PathKind::Framework => { cmd.framework_path(path); }
-            _ => { cmd.include_path(&fix_windows_verbatim_for_gcc(path)); }
+    let filesearch = sess.target_filesearch(PathKind::All);
+    for search_path in filesearch.search_paths() {
+        match search_path.kind {
+            PathKind::Framework => { cmd.framework_path(&search_path.dir); }
+            _ => { cmd.include_path(&fix_windows_verbatim_for_gcc(&search_path.dir)); }
         }
-    });
+    }
 
     let relevant_libs = codegen_results.crate_info.used_libraries.iter().filter(|l| {
         relevant_lib(sess, l)
diff --git a/src/librustc_codegen_llvm/callee.rs b/src/librustc_codegen_llvm/callee.rs
index f13eeb6..87185a2 100644
--- a/src/librustc_codegen_llvm/callee.rs
+++ b/src/librustc_codegen_llvm/callee.rs
@@ -94,7 +94,7 @@
         if instance.def.is_inline(tcx) {
             attributes::inline(cx, llfn, attributes::InlineAttr::Hint);
         }
-        attributes::from_fn_attrs(cx, llfn, Some(instance.def.def_id()));
+        attributes::from_fn_attrs(cx, llfn, Some(instance.def.def_id()), sig);
 
         let instance_def_id = instance.def_id();
 
diff --git a/src/librustc_codegen_llvm/common.rs b/src/librustc_codegen_llvm/common.rs
index 55f286e..ad14ca7 100644
--- a/src/librustc_codegen_llvm/common.rs
+++ b/src/librustc_codegen_llvm/common.rs
@@ -21,7 +21,7 @@
 use rustc_codegen_ssa::traits::*;
 
 use rustc::ty::layout::{HasDataLayout, LayoutOf, self, TyLayout, Size};
-use rustc::mir::interpret::{Scalar, AllocType, Allocation};
+use rustc::mir::interpret::{Scalar, AllocKind, Allocation};
 use consts::const_alloc_to_llvm;
 use rustc_codegen_ssa::mir::place::PlaceRef;
 
@@ -316,9 +316,9 @@
                 }
             },
             Scalar::Ptr(ptr) => {
-                let alloc_type = self.tcx.alloc_map.lock().get(ptr.alloc_id);
-                let base_addr = match alloc_type {
-                    Some(AllocType::Memory(alloc)) => {
+                let alloc_kind = self.tcx.alloc_map.lock().get(ptr.alloc_id);
+                let base_addr = match alloc_kind {
+                    Some(AllocKind::Memory(alloc)) => {
                         let init = const_alloc_to_llvm(self, alloc);
                         if alloc.mutability == Mutability::Mutable {
                             self.static_addr_of_mut(init, alloc.align, None)
@@ -326,10 +326,10 @@
                             self.static_addr_of(init, alloc.align, None)
                         }
                     }
-                    Some(AllocType::Function(fn_instance)) => {
+                    Some(AllocKind::Function(fn_instance)) => {
                         self.get_fn(fn_instance)
                     }
-                    Some(AllocType::Static(def_id)) => {
+                    Some(AllocKind::Static(def_id)) => {
                         assert!(self.tcx.is_static(def_id).is_some());
                         self.get_static(def_id)
                     }
diff --git a/src/librustc_codegen_llvm/context.rs b/src/librustc_codegen_llvm/context.rs
index 6c90937..0bd6146 100644
--- a/src/librustc_codegen_llvm/context.rs
+++ b/src/librustc_codegen_llvm/context.rs
@@ -409,7 +409,6 @@
         ));
 
         let llfn = self.declare_fn("rust_eh_unwind_resume", sig);
-        attributes::unwind(llfn, true);
         attributes::apply_target_cpu_attr(self, llfn);
         unwresume.set(Some(llfn));
         llfn
diff --git a/src/librustc_codegen_llvm/declare.rs b/src/librustc_codegen_llvm/declare.rs
index c23aab4..2964f2e 100644
--- a/src/librustc_codegen_llvm/declare.rs
+++ b/src/librustc_codegen_llvm/declare.rs
@@ -26,8 +26,7 @@
 use rustc::ty::layout::LayoutOf;
 use rustc::session::config::Sanitizer;
 use rustc_data_structures::small_c_str::SmallCStr;
-use rustc_target::spec::PanicStrategy;
-use abi::{Abi, FnType, FnTypeExt};
+use abi::{FnType, FnTypeExt};
 use attributes;
 use context::CodegenCx;
 use type_::Type;
@@ -86,10 +85,6 @@
         _ => {},
     }
 
-    if cx.tcx.sess.panic_strategy() != PanicStrategy::Unwind {
-        attributes::unwind(llfn, false);
-    }
-
     attributes::non_lazy_bind(cx.sess(), llfn);
 
     llfn
@@ -132,10 +127,6 @@
             llvm::Attribute::NoReturn.apply_llfn(Function, llfn);
         }
 
-        if sig.abi != Abi::Rust && sig.abi != Abi::RustCall {
-            attributes::unwind(llfn, false);
-        }
-
         fty.apply_attrs_llfn(llfn);
 
         llfn
diff --git a/src/librustc_codegen_llvm/intrinsic.rs b/src/librustc_codegen_llvm/intrinsic.rs
index 59608b1..8b26ada 100644
--- a/src/librustc_codegen_llvm/intrinsic.rs
+++ b/src/librustc_codegen_llvm/intrinsic.rs
@@ -1081,7 +1081,7 @@
         Abi::Rust
     ));
     let llfn = cx.define_internal_fn(name, rust_fn_sig);
-    attributes::from_fn_attrs(cx, llfn, None);
+    attributes::from_fn_attrs(cx, llfn, None, rust_fn_sig);
     let bx = Builder::new_block(cx, llfn, "entry-block");
     codegen(bx);
     llfn
@@ -1171,6 +1171,27 @@
     );
     let arg_tys = sig.inputs();
 
+    if name == "simd_select_bitmask" {
+        let in_ty = arg_tys[0];
+        let m_len = match in_ty.sty {
+            // Note that this `.unwrap()` crashes for isize/usize, that's sort
+            // of intentional as there's not currently a use case for that.
+            ty::Int(i) => i.bit_width().unwrap(),
+            ty::Uint(i) => i.bit_width().unwrap(),
+            _ => return_error!("`{}` is not an integral type", in_ty),
+        };
+        require_simd!(arg_tys[1], "argument");
+        let v_len = arg_tys[1].simd_size(tcx);
+        require!(m_len == v_len,
+                 "mismatched lengths: mask length `{}` != other vector length `{}`",
+                 m_len, v_len
+        );
+        let i1 = bx.type_i1();
+        let i1xn = bx.type_vector(i1, m_len as u64);
+        let m_i1s = bx.bitcast(args[0].immediate(), i1xn);
+        return Ok(bx.select(m_i1s, args[1].immediate(), args[2].immediate()));
+    }
+
     // every intrinsic takes a SIMD vector as its first argument
     require_simd!(arg_tys[0], "input");
     let in_ty = arg_tys[0];
diff --git a/src/librustc_codegen_llvm/llvm_util.rs b/src/librustc_codegen_llvm/llvm_util.rs
index fdb6373..12109ae 100644
--- a/src/librustc_codegen_llvm/llvm_util.rs
+++ b/src/librustc_codegen_llvm/llvm_util.rs
@@ -124,6 +124,7 @@
 ];
 
 const X86_WHITELIST: &[(&str, Option<&str>)] = &[
+    ("adx", Some("adx_target_feature")),
     ("aes", None),
     ("avx", None),
     ("avx2", None),
diff --git a/src/librustc_codegen_llvm/mono_item.rs b/src/librustc_codegen_llvm/mono_item.rs
index 1d5bcc4..9c69d7d 100644
--- a/src/librustc_codegen_llvm/mono_item.rs
+++ b/src/librustc_codegen_llvm/mono_item.rs
@@ -82,7 +82,12 @@
         if instance.def.is_inline(self.tcx) {
             attributes::inline(self, lldecl, attributes::InlineAttr::Hint);
         }
-        attributes::from_fn_attrs(self, lldecl, Some(instance.def.def_id()));
+        attributes::from_fn_attrs(
+            self,
+            lldecl,
+            Some(instance.def.def_id()),
+            mono_sig,
+        );
 
         self.instances.borrow_mut().insert(instance, lldecl);
     }
diff --git a/src/librustc_codegen_ssa/Cargo.toml b/src/librustc_codegen_ssa/Cargo.toml
index 7b1c7cf..5099449 100644
--- a/src/librustc_codegen_ssa/Cargo.toml
+++ b/src/librustc_codegen_ssa/Cargo.toml
@@ -16,7 +16,7 @@
 rustc-demangle = "0.1.4"
 memmap = "0.6"
 log = "0.4.5"
-libc = "0.2.43"
+libc = "0.2.44"
 jobserver = "0.1.11"
 
 serialize = { path = "../libserialize" }
diff --git a/src/librustc_codegen_ssa/back/link.rs b/src/librustc_codegen_ssa/back/link.rs
index 24a70dc..59102e0 100644
--- a/src/librustc_codegen_ssa/back/link.rs
+++ b/src/librustc_codegen_ssa/back/link.rs
@@ -192,11 +192,7 @@
 
     // linker and linker flavor specified via command line have precedence over what the target
     // specification specifies
-    if let Some(ret) = infer_from(
-        sess,
-        sess.opts.cg.linker.clone(),
-        sess.opts.debugging_opts.linker_flavor,
-    ) {
+    if let Some(ret) = infer_from(sess, sess.opts.cg.linker.clone(), sess.opts.cg.linker_flavor) {
         return ret;
     }
 
diff --git a/src/librustc_codegen_ssa/back/linker.rs b/src/librustc_codegen_ssa/back/linker.rs
index 2f92c42..4960c89 100644
--- a/src/librustc_codegen_ssa/back/linker.rs
+++ b/src/librustc_codegen_ssa/back/linker.rs
@@ -606,8 +606,7 @@
         self.cmd.arg("/DEBUG");
 
         // This will cause the Microsoft linker to embed .natvis info into the PDB file
-        let sysroot = self.sess.sysroot();
-        let natvis_dir_path = sysroot.join("lib\\rustlib\\etc");
+        let natvis_dir_path = self.sess.sysroot.join("lib\\rustlib\\etc");
         if let Ok(natvis_dir) = fs::read_dir(&natvis_dir_path) {
             // LLVM 5.0.0's lld-link frontend doesn't yet recognize, and chokes
             // on, the /NATVIS:... flags.  LLVM 6 (or earlier) should at worst ignore
diff --git a/src/librustc_data_structures/sorted_map.rs b/src/librustc_data_structures/sorted_map.rs
index 29d99a6..3bd3d11 100644
--- a/src/librustc_data_structures/sorted_map.rs
+++ b/src/librustc_data_structures/sorted_map.rs
@@ -10,7 +10,7 @@
 
 use std::borrow::Borrow;
 use std::cmp::Ordering;
-use std::convert::From;
+use std::iter::FromIterator;
 use std::mem;
 use std::ops::{RangeBounds, Bound, Index, IndexMut};
 
@@ -25,11 +25,10 @@
 #[derive(Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Default, Debug, RustcEncodable,
          RustcDecodable)]
 pub struct SortedMap<K: Ord, V> {
-    data: Vec<(K,V)>
+    data: Vec<(K, V)>
 }
 
 impl<K: Ord, V> SortedMap<K, V> {
-
     #[inline]
     pub fn new() -> SortedMap<K, V> {
         SortedMap {
@@ -82,7 +81,10 @@
     }
 
     #[inline]
-    pub fn get(&self, key: &K) -> Option<&V> {
+    pub fn get<Q>(&self, key: &Q) -> Option<&V>
+        where K: Borrow<Q>,
+              Q: Ord + ?Sized
+    {
         match self.lookup_index_for(key) {
             Ok(index) => {
                 unsafe {
@@ -96,7 +98,10 @@
     }
 
     #[inline]
-    pub fn get_mut(&mut self, key: &K) -> Option<&mut V> {
+    pub fn get_mut<Q>(&mut self, key: &Q) -> Option<&mut V>
+        where K: Borrow<Q>,
+              Q: Ord + ?Sized
+    {
         match self.lookup_index_for(key) {
             Ok(index) => {
                 unsafe {
@@ -122,13 +127,13 @@
 
     /// Iterate over the keys, sorted
     #[inline]
-    pub fn keys(&self) -> impl Iterator<Item=&K> + ExactSizeIterator {
+    pub fn keys(&self) -> impl Iterator<Item = &K> + ExactSizeIterator {
         self.data.iter().map(|&(ref k, _)| k)
     }
 
     /// Iterate over values, sorted by key
     #[inline]
-    pub fn values(&self) -> impl Iterator<Item=&V> + ExactSizeIterator {
+    pub fn values(&self) -> impl Iterator<Item = &V> + ExactSizeIterator {
         self.data.iter().map(|&(_, ref v)| v)
     }
 
@@ -138,6 +143,11 @@
     }
 
     #[inline]
+    pub fn is_empty(&self) -> bool {
+        self.len() == 0
+    }
+
+    #[inline]
     pub fn range<R>(&self, range: R) -> &[(K, V)]
         where R: RangeBounds<K>
     {
@@ -207,8 +217,11 @@
 
     /// Looks up the key in `self.data` via `slice::binary_search()`.
     #[inline(always)]
-    fn lookup_index_for(&self, key: &K) -> Result<usize, usize> {
-        self.data.binary_search_by(|&(ref x, _)| x.cmp(key))
+    fn lookup_index_for<Q>(&self, key: &Q) -> Result<usize, usize>
+        where K: Borrow<Q>,
+              Q: Ord + ?Sized
+    {
+        self.data.binary_search_by(|&(ref x, _)| x.borrow().cmp(key))
     }
 
     #[inline]
@@ -247,38 +260,54 @@
 
         (start, end)
     }
+
+    #[inline]
+    pub fn contains_key<Q>(&self, key: &Q) -> bool
+        where K: Borrow<Q>,
+              Q: Ord + ?Sized
+    {
+        self.get(key).is_some()
+    }
 }
 
 impl<K: Ord, V> IntoIterator for SortedMap<K, V> {
     type Item = (K, V);
     type IntoIter = ::std::vec::IntoIter<(K, V)>;
+
     fn into_iter(self) -> Self::IntoIter {
         self.data.into_iter()
     }
 }
 
-impl<K: Ord, V, Q: Borrow<K>> Index<Q> for SortedMap<K, V> {
+impl<'a, K, Q, V> Index<&'a Q> for SortedMap<K, V>
+    where K: Ord + Borrow<Q>,
+          Q: Ord + ?Sized
+{
     type Output = V;
-    fn index(&self, index: Q) -> &Self::Output {
-        let k: &K = index.borrow();
-        self.get(k).unwrap()
+
+    fn index(&self, key: &Q) -> &Self::Output {
+        self.get(key).expect("no entry found for key")
     }
 }
 
-impl<K: Ord, V, Q: Borrow<K>> IndexMut<Q> for SortedMap<K, V> {
-    fn index_mut(&mut self, index: Q) -> &mut Self::Output {
-        let k: &K = index.borrow();
-        self.get_mut(k).unwrap()
+impl<'a, K, Q, V> IndexMut<&'a Q> for SortedMap<K, V>
+    where K: Ord + Borrow<Q>,
+          Q: Ord + ?Sized
+{
+    fn index_mut(&mut self, key: &Q) -> &mut Self::Output {
+        self.get_mut(key).expect("no entry found for key")
     }
 }
 
-impl<K: Ord, V, I: Iterator<Item=(K, V)>> From<I> for SortedMap<K, V> {
-    fn from(data: I) -> Self {
-        let mut data: Vec<(K, V)> = data.collect();
+impl<K: Ord, V> FromIterator<(K, V)> for SortedMap<K, V> {
+    fn from_iter<T: IntoIterator<Item = (K, V)>>(iter: T) -> Self {
+        let mut data: Vec<(K, V)> = iter.into_iter().collect();
+
         data.sort_unstable_by(|&(ref k1, _), &(ref k2, _)| k1.cmp(k2));
         data.dedup_by(|&mut (ref k1, _), &mut (ref k2, _)| {
             k1.cmp(k2) == Ordering::Equal
         });
+
         SortedMap {
             data
         }
diff --git a/src/librustc_driver/driver.rs b/src/librustc_driver/driver.rs
index f2edcdc..b26d81b 100644
--- a/src/librustc_driver/driver.rs
+++ b/src/librustc_driver/driver.rs
@@ -975,7 +975,7 @@
         let mut old_path = OsString::new();
         if cfg!(windows) {
             old_path = env::var_os("PATH").unwrap_or(old_path);
-            let mut new_path = sess.host_filesearch(PathKind::All).get_dylib_search_paths();
+            let mut new_path = sess.host_filesearch(PathKind::All).search_path_dirs();
             for path in env::split_paths(&old_path) {
                 if !new_path.contains(&path) {
                     new_path.push(path);
diff --git a/src/librustc_driver/lib.rs b/src/librustc_driver/lib.rs
index 39777e0..41c9b22 100644
--- a/src/librustc_driver/lib.rs
+++ b/src/librustc_driver/lib.rs
@@ -1042,7 +1042,7 @@
                     targets.sort();
                     println!("{}", targets.join("\n"));
                 },
-                Sysroot => println!("{}", sess.sysroot().display()),
+                Sysroot => println!("{}", sess.sysroot.display()),
                 TargetSpec => println!("{}", sess.target.target.to_json().pretty()),
                 FileNames | CrateName => {
                     let input = input.unwrap_or_else(||
diff --git a/src/librustc_errors/emitter.rs b/src/librustc_errors/emitter.rs
index ae9f6a5..7bd0f0f 100644
--- a/src/librustc_errors/emitter.rs
+++ b/src/librustc_errors/emitter.rs
@@ -1262,7 +1262,7 @@
 
                         // Do not underline the leading...
                         let start = part.snippet.len()
-                            .saturating_sub(part.snippet.trim_left().len());
+                            .saturating_sub(part.snippet.trim_start().len());
                         // ...or trailing spaces. Account for substitutions containing unicode
                         // characters.
                         let sub_len = part.snippet.trim().chars().fold(0, |acc, ch| {
diff --git a/src/librustc_lint/nonstandard_style.rs b/src/librustc_lint/nonstandard_style.rs
index 13be50e..e071c34 100644
--- a/src/librustc_lint/nonstandard_style.rs
+++ b/src/librustc_lint/nonstandard_style.rs
@@ -167,7 +167,7 @@
     fn to_snake_case(mut str: &str) -> String {
         let mut words = vec![];
         // Preserve leading underscores
-        str = str.trim_left_matches(|c: char| {
+        str = str.trim_start_matches(|c: char| {
             if c == '_' {
                 words.push(String::new());
                 true
@@ -199,7 +199,7 @@
             if ident.is_empty() {
                 return true;
             }
-            let ident = ident.trim_left_matches('\'');
+            let ident = ident.trim_start_matches('\'');
             let ident = ident.trim_matches('_');
 
             let mut allow_underscore = true;
diff --git a/src/librustc_llvm/build.rs b/src/librustc_llvm/build.rs
index 7d01ed5..ce48208 100644
--- a/src/librustc_llvm/build.rs
+++ b/src/librustc_llvm/build.rs
@@ -192,11 +192,11 @@
             // On MSVC llvm-config will print the full name to libraries, but
             // we're only interested in the name part
             let name = Path::new(lib).file_name().unwrap().to_str().unwrap();
-            name.trim_right_matches(".lib")
+            name.trim_end_matches(".lib")
         } else if lib.ends_with(".lib") {
             // Some MSVC libraries just come up with `.lib` tacked on, so chop
             // that off
-            lib.trim_right_matches(".lib")
+            lib.trim_end_matches(".lib")
         } else {
             continue;
         };
diff --git a/src/librustc_lsan/Cargo.toml b/src/librustc_lsan/Cargo.toml
index 2573825..a8e11df 100644
--- a/src/librustc_lsan/Cargo.toml
+++ b/src/librustc_lsan/Cargo.toml
@@ -16,4 +16,4 @@
 [dependencies]
 alloc = { path = "../liballoc" }
 core = { path = "../libcore" }
-compiler_builtins = { path = "../rustc/compiler_builtins_shim" }
+compiler_builtins = "0.1.0"
diff --git a/src/librustc_metadata/locator.rs b/src/librustc_metadata/locator.rs
index 1f298f6..f01ed9e 100644
--- a/src/librustc_metadata/locator.rs
+++ b/src/librustc_metadata/locator.rs
@@ -678,7 +678,7 @@
             // candidates are all canonicalized, so we canonicalize the sysroot
             // as well.
             if let Some((ref prev, _)) = ret {
-                let sysroot = self.sess.sysroot();
+                let sysroot = &self.sess.sysroot;
                 let sysroot = sysroot.canonicalize()
                                      .unwrap_or_else(|_| sysroot.to_path_buf());
                 if prev.starts_with(&sysroot) {
diff --git a/src/librustc_mir/borrow_check/move_errors.rs b/src/librustc_mir/borrow_check/move_errors.rs
index db60017..fb93c41 100644
--- a/src/librustc_mir/borrow_check/move_errors.rs
+++ b/src/librustc_mir/borrow_check/move_errors.rs
@@ -426,13 +426,13 @@
                     .span_to_snippet(pat_span)
                     .unwrap();
                 if pat_snippet.starts_with('&') {
-                    let pat_snippet = pat_snippet[1..].trim_left();
+                    let pat_snippet = pat_snippet[1..].trim_start();
                     let suggestion;
                     let to_remove;
                     if pat_snippet.starts_with("mut")
                         && pat_snippet["mut".len()..].starts_with(Pattern_White_Space)
                     {
-                        suggestion = pat_snippet["mut".len()..].trim_left();
+                        suggestion = pat_snippet["mut".len()..].trim_start();
                         to_remove = "&mut";
                     } else {
                         suggestion = pat_snippet;
diff --git a/src/librustc_mir/build/matches/simplify.rs b/src/librustc_mir/build/matches/simplify.rs
index cfea357..328b330 100644
--- a/src/librustc_mir/build/matches/simplify.rs
+++ b/src/librustc_mir/build/matches/simplify.rs
@@ -26,6 +26,10 @@
 use build::matches::{Ascription, Binding, MatchPair, Candidate};
 use hair::*;
 use rustc::mir::*;
+use rustc::ty;
+use rustc::ty::layout::{Integer, IntegerExt, Size};
+use syntax::attr::{SignedInt, UnsignedInt};
+use rustc::hir::RangeEnd;
 
 use std::mem;
 
@@ -62,6 +66,7 @@
                                  match_pair: MatchPair<'pat, 'tcx>,
                                  candidate: &mut Candidate<'pat, 'tcx>)
                                  -> Result<(), MatchPair<'pat, 'tcx>> {
+        let tcx = self.hir.tcx();
         match *match_pair.pattern.kind {
             PatternKind::AscribeUserType { ref subpattern, ref user_ty, user_ty_span } => {
                 candidate.ascriptions.push(Ascription {
@@ -104,7 +109,34 @@
                 Err(match_pair)
             }
 
-            PatternKind::Range { .. } => {
+            PatternKind::Range { lo, hi, ty, end } => {
+                let range = match ty.sty {
+                    ty::Char => {
+                        Some(('\u{0000}' as u128, '\u{10FFFF}' as u128, Size::from_bits(32)))
+                    }
+                    ty::Int(ity) => {
+                        // FIXME(49937): refactor these bit manipulations into interpret.
+                        let size = Integer::from_attr(&tcx, SignedInt(ity)).size();
+                        let min = 1u128 << (size.bits() - 1);
+                        let max = (1u128 << (size.bits() - 1)) - 1;
+                        Some((min, max, size))
+                    }
+                    ty::Uint(uty) => {
+                        // FIXME(49937): refactor these bit manipulations into interpret.
+                        let size = Integer::from_attr(&tcx, UnsignedInt(uty)).size();
+                        let max = !0u128 >> (128 - size.bits());
+                        Some((0, max, size))
+                    }
+                    _ => None,
+                };
+                if let Some((min, max, sz)) = range {
+                    if let (Some(lo), Some(hi)) = (lo.val.try_to_bits(sz), hi.val.try_to_bits(sz)) {
+                        if lo <= min && (hi > max || hi == max && end == RangeEnd::Included) {
+                            // Irrefutable pattern match.
+                            return Ok(());
+                        }
+                    }
+                }
                 Err(match_pair)
             }
 
diff --git a/src/librustc_mir/build/mod.rs b/src/librustc_mir/build/mod.rs
index b0601b3..ab52d9b 100644
--- a/src/librustc_mir/build/mod.rs
+++ b/src/librustc_mir/build/mod.rs
@@ -628,12 +628,7 @@
     // unwind anyway. Don't stop them.
     let attrs = &tcx.get_attrs(fn_def_id);
     match attr::find_unwind_attr(Some(tcx.sess.diagnostic()), attrs) {
-        None => {
-            // FIXME(rust-lang/rust#48251) -- Had to disable
-            // abort-on-panic for backwards compatibility reasons.
-            false
-        }
-
+        None => true,
         Some(UnwindAttr::Allowed) => false,
         Some(UnwindAttr::Aborts) => true,
     }
diff --git a/src/librustc_mir/hair/pattern/_match.rs b/src/librustc_mir/hair/pattern/_match.rs
index 4c77350..5cfcc16 100644
--- a/src/librustc_mir/hair/pattern/_match.rs
+++ b/src/librustc_mir/hair/pattern/_match.rs
@@ -178,11 +178,11 @@
 
 use rustc::hir::def_id::DefId;
 use rustc::hir::RangeEnd;
-use rustc::ty::{self, Ty, TyCtxt, TypeFoldable};
-use rustc::ty::layout::{Integer, IntegerExt, VariantIdx};
+use rustc::ty::{self, Ty, TyCtxt, TypeFoldable, Const};
+use rustc::ty::layout::{Integer, IntegerExt, VariantIdx, Size};
 
 use rustc::mir::Field;
-use rustc::mir::interpret::ConstValue;
+use rustc::mir::interpret::{ConstValue, Pointer, Scalar};
 use rustc::util::common::ErrorReported;
 
 use syntax::attr::{SignedInt, UnsignedInt};
@@ -200,14 +200,60 @@
 pub fn expand_pattern<'a, 'tcx>(cx: &MatchCheckCtxt<'a, 'tcx>, pat: Pattern<'tcx>)
                                 -> &'a Pattern<'tcx>
 {
-    cx.pattern_arena.alloc(LiteralExpander.fold_pattern(&pat))
+    cx.pattern_arena.alloc(LiteralExpander { tcx: cx.tcx }.fold_pattern(&pat))
 }
 
-struct LiteralExpander;
-impl<'tcx> PatternFolder<'tcx> for LiteralExpander {
+struct LiteralExpander<'a, 'tcx> {
+    tcx: TyCtxt<'a, 'tcx, 'tcx>
+}
+
+impl<'a, 'tcx> LiteralExpander<'a, 'tcx> {
+    /// Derefs `val` and potentially unsizes the value if `crty` is an array and `rty` a slice.
+    ///
+    /// `crty` and `rty` can differ because you can use array constants in the presence of slice
+    /// patterns. So the pattern may end up being a slice, but the constant is an array. We convert
+    /// the array to a slice in that case.
+    fn fold_const_value_deref(
+        &mut self,
+        val: ConstValue<'tcx>,
+        // the pattern's pointee type
+        rty: Ty<'tcx>,
+        // the constant's pointee type
+        crty: Ty<'tcx>,
+    ) -> ConstValue<'tcx> {
+        match (val, &crty.sty, &rty.sty) {
+            // the easy case, deref a reference
+            (ConstValue::Scalar(Scalar::Ptr(p)), x, y) if x == y => ConstValue::ByRef(
+                p.alloc_id,
+                self.tcx.alloc_map.lock().unwrap_memory(p.alloc_id),
+                p.offset,
+            ),
+            // unsize array to slice if pattern is array but match value or other patterns are slice
+            (ConstValue::Scalar(Scalar::Ptr(p)), ty::Array(t, n), ty::Slice(u)) => {
+                assert_eq!(t, u);
+                ConstValue::ScalarPair(
+                    Scalar::Ptr(p),
+                    n.val.try_to_scalar().unwrap(),
+                )
+            },
+            // fat pointers stay the same
+            (ConstValue::ScalarPair(..), _, _) => val,
+            // FIXME(oli-obk): this is reachable for `const FOO: &&&u32 = &&&42;` being used
+            _ => bug!("cannot deref {:#?}, {} -> {}", val, crty, rty),
+        }
+    }
+}
+
+impl<'a, 'tcx> PatternFolder<'tcx> for LiteralExpander<'a, 'tcx> {
     fn fold_pattern(&mut self, pat: &Pattern<'tcx>) -> Pattern<'tcx> {
         match (&pat.ty.sty, &*pat.kind) {
-            (&ty::Ref(_, rty, _), &PatternKind::Constant { ref value }) => {
+            (
+                &ty::Ref(_, rty, _),
+                &PatternKind::Constant { value: Const {
+                    val,
+                    ty: ty::TyS { sty: ty::Ref(_, crty, _), .. },
+                } },
+            ) => {
                 Pattern {
                     ty: pat.ty,
                     span: pat.span,
@@ -215,7 +261,11 @@
                         subpattern: Pattern {
                             ty: rty,
                             span: pat.span,
-                            kind: box PatternKind::Constant { value: value.clone() },
+                            kind: box PatternKind::Constant { value: Const::from_const_value(
+                                self.tcx,
+                                self.fold_const_value_deref(*val, rty, crty),
+                                rty,
+                            ) },
                         }
                     }
                 }
@@ -732,15 +782,17 @@
     for row in patterns {
         match *row.kind {
             PatternKind::Constant { value } => {
-                if let Some(ptr) = value.to_ptr() {
-                    let is_array_ptr = value.ty
-                        .builtin_deref(true)
-                        .and_then(|t| t.ty.builtin_index())
-                        .map_or(false, |t| t == cx.tcx.types.u8);
-                    if is_array_ptr {
-                        let alloc = cx.tcx.alloc_map.lock().unwrap_memory(ptr.alloc_id);
-                        max_fixed_len = cmp::max(max_fixed_len, alloc.bytes.len() as u64);
-                    }
+                // extract the length of an array/slice from a constant
+                match (value.val, &value.ty.sty) {
+                    (_, ty::Array(_, n)) => max_fixed_len = cmp::max(
+                        max_fixed_len,
+                        n.unwrap_usize(cx.tcx),
+                    ),
+                    (ConstValue::ScalarPair(_, n), ty::Slice(_)) => max_fixed_len = cmp::max(
+                        max_fixed_len,
+                        n.to_usize(&cx.tcx).unwrap(),
+                    ),
+                    _ => {},
                 }
             }
             PatternKind::Slice { ref prefix, slice: None, ref suffix } => {
@@ -1348,28 +1400,62 @@
     }
 }
 
-fn slice_pat_covered_by_constructor<'tcx>(
+// checks whether a constant is equal to a user-written slice pattern. Only supports byte slices,
+// meaning all other types will compare unequal and thus equal patterns often do not cause the
+// second pattern to lint about unreachable match arms.
+fn slice_pat_covered_by_const<'tcx>(
     tcx: TyCtxt<'_, 'tcx, '_>,
     _span: Span,
-    ctor: &Constructor,
+    const_val: &ty::Const<'tcx>,
     prefix: &[Pattern<'tcx>],
     slice: &Option<Pattern<'tcx>>,
     suffix: &[Pattern<'tcx>]
 ) -> Result<bool, ErrorReported> {
-    let data: &[u8] = match *ctor {
-        ConstantValue(const_val) => {
-            let val = match const_val.val {
-                ConstValue::Unevaluated(..) |
-                ConstValue::ByRef(..) => bug!("unexpected ConstValue: {:?}", const_val),
-                ConstValue::Scalar(val) | ConstValue::ScalarPair(val, _) => val,
-            };
-            if let Ok(ptr) = val.to_ptr() {
-                tcx.alloc_map.lock().unwrap_memory(ptr.alloc_id).bytes.as_ref()
-            } else {
-                bug!("unexpected non-ptr ConstantValue")
+    let data: &[u8] = match (const_val.val, &const_val.ty.sty) {
+        (ConstValue::ByRef(id, alloc, offset), ty::Array(t, n)) => {
+            if *t != tcx.types.u8 {
+                // FIXME(oli-obk): can't mix const patterns with slice patterns and get
+                // any sort of exhaustiveness/unreachable check yet
+                // This solely means that we don't lint about unreachable patterns, even if some
+                // are definitely unreachable.
+                return Ok(false);
             }
-        }
-        _ => bug!()
+            let ptr = Pointer::new(id, offset);
+            let n = n.assert_usize(tcx).unwrap();
+            alloc.get_bytes(&tcx, ptr, Size::from_bytes(n)).unwrap()
+        },
+        // a slice fat pointer to a zero length slice
+        (ConstValue::ScalarPair(Scalar::Bits { .. }, n), ty::Slice(t)) => {
+            if *t != tcx.types.u8 {
+                // FIXME(oli-obk): can't mix const patterns with slice patterns and get
+                // any sort of exhaustiveness/unreachable check yet
+                // This solely means that we don't lint about unreachable patterns, even if some
+                // are definitely unreachable.
+                return Ok(false);
+            }
+            assert_eq!(n.to_usize(&tcx).unwrap(), 0);
+            &[]
+        },
+        //
+        (ConstValue::ScalarPair(Scalar::Ptr(ptr), n), ty::Slice(t)) => {
+            if *t != tcx.types.u8 {
+                // FIXME(oli-obk): can't mix const patterns with slice patterns and get
+                // any sort of exhaustiveness/unreachable check yet
+                // This solely means that we don't lint about unreachable patterns, even if some
+                // are definitely unreachable.
+                return Ok(false);
+            }
+            let n = n.to_usize(&tcx).unwrap();
+            tcx.alloc_map
+                .lock()
+                .unwrap_memory(ptr.alloc_id)
+                .get_bytes(&tcx, ptr, Size::from_bytes(n))
+                .unwrap()
+        },
+        _ => bug!(
+            "slice_pat_covered_by_const: {:#?}, {:#?}, {:#?}, {:#?}",
+            const_val, prefix, slice, suffix,
+        ),
     };
 
     let pat_len = prefix.len() + suffix.len();
@@ -1675,22 +1761,23 @@
                     // necessarily point to memory, they are usually just integers. The only time
                     // they should be pointing to memory is when they are subslices of nonzero
                     // slices
-                    let (opt_ptr, n, ty) = match value.ty.builtin_deref(false).unwrap().ty.sty {
-                        ty::TyKind::Array(t, n) => (value.to_ptr(), n.unwrap_usize(cx.tcx), t),
-                        ty::TyKind::Slice(t) => {
-                            match value.val {
-                                ConstValue::ScalarPair(ptr, n) => (
-                                    ptr.to_ptr().ok(),
-                                    n.to_bits(cx.tcx.data_layout.pointer_size).unwrap() as u64,
-                                    t,
-                                ),
-                                _ => span_bug!(
-                                    pat.span,
-                                    "slice pattern constant must be scalar pair but is {:?}",
-                                    value,
-                                ),
-                            }
-                        },
+                    let (opt_ptr, n, ty) = match (value.val, &value.ty.sty) {
+                        (ConstValue::ByRef(id, alloc, offset), ty::TyKind::Array(t, n)) => (
+                            Some((
+                                Pointer::new(id, offset),
+                                alloc,
+                            )),
+                            n.unwrap_usize(cx.tcx),
+                            t,
+                        ),
+                        (ConstValue::ScalarPair(ptr, n), ty::TyKind::Slice(t)) => (
+                            ptr.to_ptr().ok().map(|ptr| (
+                                ptr,
+                                cx.tcx.alloc_map.lock().unwrap_memory(ptr.alloc_id),
+                            )),
+                            n.to_bits(cx.tcx.data_layout.pointer_size).unwrap() as u64,
+                            t,
+                        ),
                         _ => span_bug!(
                             pat.span,
                             "unexpected const-val {:?} with ctor {:?}",
@@ -1702,8 +1789,7 @@
                         // convert a constant slice/array pattern to a list of patterns.
                         match (n, opt_ptr) {
                             (0, _) => Some(SmallVec::new()),
-                            (_, Some(ptr)) => {
-                                let alloc = cx.tcx.alloc_map.lock().unwrap_memory(ptr.alloc_id);
+                            (_, Some((ptr, alloc))) => {
                                 let layout = cx.tcx.layout_of(cx.param_env.and(ty)).ok()?;
                                 (0..n).map(|i| {
                                     let ptr = ptr.offset(layout.size * i, &cx.tcx).ok()?;
@@ -1766,10 +1852,8 @@
                         None
                     }
                 }
-                ConstantValue(..) => {
-                    match slice_pat_covered_by_constructor(
-                        cx.tcx, pat.span, constructor, prefix, slice, suffix
-                            ) {
+                ConstantValue(cv) => {
+                    match slice_pat_covered_by_const(cx.tcx, pat.span, cv, prefix, slice, suffix) {
                         Ok(true) => Some(smallvec![]),
                         Ok(false) => None,
                         Err(ErrorReported) => None
diff --git a/src/librustc_mir/hair/pattern/mod.rs b/src/librustc_mir/hair/pattern/mod.rs
index d695a64..ddd6a70 100644
--- a/src/librustc_mir/hair/pattern/mod.rs
+++ b/src/librustc_mir/hair/pattern/mod.rs
@@ -1259,34 +1259,32 @@
         }
     }
 
-    if let ty::Ref(_, rty, _) = ty.value.sty {
-        if let ty::Str = rty.sty {
-            match (a.val, b.val) {
-                (
-                    ConstValue::ScalarPair(
-                        Scalar::Ptr(ptr_a),
-                        len_a,
-                    ),
-                    ConstValue::ScalarPair(
-                        Scalar::Ptr(ptr_b),
-                        len_b,
-                    ),
-                ) if ptr_a.offset.bytes() == 0 && ptr_b.offset.bytes() == 0 => {
-                    if let Ok(len_a) = len_a.to_bits(tcx.data_layout.pointer_size) {
-                        if let Ok(len_b) = len_b.to_bits(tcx.data_layout.pointer_size) {
-                            if len_a == len_b {
-                                let map = tcx.alloc_map.lock();
-                                let alloc_a = map.unwrap_memory(ptr_a.alloc_id);
-                                let alloc_b = map.unwrap_memory(ptr_b.alloc_id);
-                                if alloc_a.bytes.len() as u128 == len_a {
-                                    return from_bool(alloc_a == alloc_b);
-                                }
+    if let ty::Str = ty.value.sty {
+        match (a.val, b.val) {
+            (
+                ConstValue::ScalarPair(
+                    Scalar::Ptr(ptr_a),
+                    len_a,
+                ),
+                ConstValue::ScalarPair(
+                    Scalar::Ptr(ptr_b),
+                    len_b,
+                ),
+            ) if ptr_a.offset.bytes() == 0 && ptr_b.offset.bytes() == 0 => {
+                if let Ok(len_a) = len_a.to_bits(tcx.data_layout.pointer_size) {
+                    if let Ok(len_b) = len_b.to_bits(tcx.data_layout.pointer_size) {
+                        if len_a == len_b {
+                            let map = tcx.alloc_map.lock();
+                            let alloc_a = map.unwrap_memory(ptr_a.alloc_id);
+                            let alloc_b = map.unwrap_memory(ptr_b.alloc_id);
+                            if alloc_a.bytes.len() as u128 == len_a {
+                                return from_bool(alloc_a == alloc_b);
                             }
                         }
                     }
                 }
-                _ => (),
             }
+            _ => (),
         }
     }
 
diff --git a/src/librustc_mir/interpret/intrinsics.rs b/src/librustc_mir/interpret/intrinsics.rs
index bbee6e0..cbe2e25 100644
--- a/src/librustc_mir/interpret/intrinsics.rs
+++ b/src/librustc_mir/interpret/intrinsics.rs
@@ -103,7 +103,7 @@
                     if bits == 0 {
                         return err!(Intrinsic(format!("{} called on 0", intrinsic_name)));
                     }
-                    numeric_intrinsic(intrinsic_name.trim_right_matches("_nonzero"), bits, kind)?
+                    numeric_intrinsic(intrinsic_name.trim_end_matches("_nonzero"), bits, kind)?
                 } else {
                     numeric_intrinsic(intrinsic_name, bits, kind)?
                 };
diff --git a/src/librustc_mir/interpret/memory.rs b/src/librustc_mir/interpret/memory.rs
index e32abb9..420fe26 100644
--- a/src/librustc_mir/interpret/memory.rs
+++ b/src/librustc_mir/interpret/memory.rs
@@ -29,7 +29,7 @@
 
 use super::{
     Pointer, AllocId, Allocation, GlobalId, AllocationExtra,
-    EvalResult, Scalar, EvalErrorKind, AllocType, PointerArithmetic,
+    EvalResult, Scalar, EvalErrorKind, AllocKind, PointerArithmetic,
     Machine, AllocMap, MayLeak, ErrorHandled, InboundsCheck,
 };
 
@@ -204,12 +204,12 @@
             None => {
                 // Deallocating static memory -- always an error
                 return match self.tcx.alloc_map.lock().get(ptr.alloc_id) {
-                    Some(AllocType::Function(..)) => err!(DeallocatedWrongMemoryKind(
+                    Some(AllocKind::Function(..)) => err!(DeallocatedWrongMemoryKind(
                         "function".to_string(),
                         format!("{:?}", kind),
                     )),
-                    Some(AllocType::Static(..)) |
-                    Some(AllocType::Memory(..)) => err!(DeallocatedWrongMemoryKind(
+                    Some(AllocKind::Static(..)) |
+                    Some(AllocKind::Memory(..)) => err!(DeallocatedWrongMemoryKind(
                         "static".to_string(),
                         format!("{:?}", kind),
                     )),
@@ -326,15 +326,15 @@
     ) -> EvalResult<'tcx, Cow<'tcx, Allocation<M::PointerTag, M::AllocExtra>>> {
         let alloc = tcx.alloc_map.lock().get(id);
         let def_id = match alloc {
-            Some(AllocType::Memory(mem)) => {
+            Some(AllocKind::Memory(mem)) => {
                 // We got tcx memory. Let the machine figure out whether and how to
                 // turn that into memory with the right pointer tag.
                 return Ok(M::adjust_static_allocation(mem, memory_extra))
             }
-            Some(AllocType::Function(..)) => {
+            Some(AllocKind::Function(..)) => {
                 return err!(DerefFunctionPointer)
             }
-            Some(AllocType::Static(did)) => {
+            Some(AllocKind::Static(did)) => {
                 did
             }
             None =>
@@ -435,8 +435,8 @@
         }
         // Could also be a fn ptr or extern static
         match self.tcx.alloc_map.lock().get(id) {
-            Some(AllocType::Function(..)) => (Size::ZERO, Align::from_bytes(1).unwrap()),
-            Some(AllocType::Static(did)) => {
+            Some(AllocKind::Function(..)) => (Size::ZERO, Align::from_bytes(1).unwrap()),
+            Some(AllocKind::Static(did)) => {
                 // The only way `get` couldn't have worked here is if this is an extern static
                 assert!(self.tcx.is_foreign_item(did));
                 // Use size and align of the type
@@ -459,7 +459,7 @@
         }
         trace!("reading fn ptr: {}", ptr.alloc_id);
         match self.tcx.alloc_map.lock().get(ptr.alloc_id) {
-            Some(AllocType::Function(instance)) => Ok(instance),
+            Some(AllocKind::Function(instance)) => Ok(instance),
             _ => Err(EvalErrorKind::ExecuteMemory.into()),
         }
     }
@@ -557,16 +557,16 @@
                 Err(()) => {
                     // static alloc?
                     match self.tcx.alloc_map.lock().get(id) {
-                        Some(AllocType::Memory(alloc)) => {
+                        Some(AllocKind::Memory(alloc)) => {
                             self.dump_alloc_helper(
                                 &mut allocs_seen, &mut allocs_to_print,
                                 msg, alloc, " (immutable)".to_owned()
                             );
                         }
-                        Some(AllocType::Function(func)) => {
+                        Some(AllocKind::Function(func)) => {
                             trace!("{} {}", msg, func);
                         }
-                        Some(AllocType::Static(did)) => {
+                        Some(AllocKind::Static(did)) => {
                             trace!("{} {:?}", msg, did);
                         }
                         None => {
@@ -638,7 +638,7 @@
         // ensure llvm knows not to put this into immutable memory
         alloc.mutability = mutability;
         let alloc = self.tcx.intern_const_alloc(alloc);
-        self.tcx.alloc_map.lock().set_id_memory(alloc_id, alloc);
+        self.tcx.alloc_map.lock().set_alloc_id_memory(alloc_id, alloc);
         // recurse into inner allocations
         for &(_, alloc) in alloc.relocations.values() {
             // FIXME: Reusing the mutability here is likely incorrect.  It is originally
diff --git a/src/librustc_mir/interpret/validity.rs b/src/librustc_mir/interpret/validity.rs
index 4f17373..c7bfea8 100644
--- a/src/librustc_mir/interpret/validity.rs
+++ b/src/librustc_mir/interpret/validity.rs
@@ -17,7 +17,7 @@
 use rustc::ty;
 use rustc_data_structures::fx::FxHashSet;
 use rustc::mir::interpret::{
-    Scalar, AllocType, EvalResult, EvalErrorKind,
+    Scalar, AllocKind, EvalResult, EvalErrorKind,
 };
 
 use super::{
@@ -388,7 +388,7 @@
                             "integer pointer in non-ZST reference", self.path);
                         // Skip validation entirely for some external statics
                         let alloc_kind = self.ecx.tcx.alloc_map.lock().get(ptr.alloc_id);
-                        if let Some(AllocType::Static(did)) = alloc_kind {
+                        if let Some(AllocKind::Static(did)) = alloc_kind {
                             // `extern static` cannot be validated as they have no body.
                             // FIXME: Statics from other crates are also skipped.
                             // They might be checked at a different type, but for now we
diff --git a/src/librustc_mir/monomorphize/collector.rs b/src/librustc_mir/monomorphize/collector.rs
index c962a24..a6239a8 100644
--- a/src/librustc_mir/monomorphize/collector.rs
+++ b/src/librustc_mir/monomorphize/collector.rs
@@ -197,7 +197,7 @@
 use rustc::mir::{self, Location, Promoted};
 use rustc::mir::visit::Visitor as MirVisitor;
 use rustc::mir::mono::MonoItem;
-use rustc::mir::interpret::{Scalar, GlobalId, AllocType, ErrorHandled};
+use rustc::mir::interpret::{Scalar, GlobalId, AllocKind, ErrorHandled};
 
 use monomorphize::{self, Instance};
 use rustc::util::nodemap::{FxHashSet, FxHashMap, DefIdMap};
@@ -1161,22 +1161,22 @@
     alloc_id: AllocId,
     output: &mut Vec<MonoItem<'tcx>>,
 ) {
-    let alloc_type = tcx.alloc_map.lock().get(alloc_id);
-    match alloc_type {
-        Some(AllocType::Static(did)) => {
+    let alloc_kind = tcx.alloc_map.lock().get(alloc_id);
+    match alloc_kind {
+        Some(AllocKind::Static(did)) => {
             let instance = Instance::mono(tcx, did);
             if should_monomorphize_locally(tcx, &instance) {
                 trace!("collecting static {:?}", did);
                 output.push(MonoItem::Static(did));
             }
         }
-        Some(AllocType::Memory(alloc)) => {
+        Some(AllocKind::Memory(alloc)) => {
             trace!("collecting {:?} with {:#?}", alloc_id, alloc);
             for &((), inner) in alloc.relocations.values() {
                 collect_miri(tcx, inner, output);
             }
         },
-        Some(AllocType::Function(fn_instance)) => {
+        Some(AllocKind::Function(fn_instance)) => {
             if should_monomorphize_locally(tcx, &fn_instance) {
                 trace!("collecting {:?} with {:#?}", alloc_id, fn_instance);
                 output.push(create_fn_mono_item(fn_instance));
diff --git a/src/librustc_msan/Cargo.toml b/src/librustc_msan/Cargo.toml
index 2916567..78c39d0 100644
--- a/src/librustc_msan/Cargo.toml
+++ b/src/librustc_msan/Cargo.toml
@@ -16,4 +16,4 @@
 [dependencies]
 alloc = { path = "../liballoc" }
 core = { path = "../libcore" }
-compiler_builtins = { path = "../rustc/compiler_builtins_shim" }
+compiler_builtins = "0.1.0"
diff --git a/src/librustc_resolve/diagnostics.rs b/src/librustc_resolve/diagnostics.rs
index 2681295..7730239 100644
--- a/src/librustc_resolve/diagnostics.rs
+++ b/src/librustc_resolve/diagnostics.rs
@@ -295,9 +295,8 @@
 Erroneous code example:
 
 ```compile_fail,E0259
-# #![feature(libc)]
 extern crate core;
-extern crate libc as core;
+extern crate std as core;
 
 fn main() {}
 ```
@@ -308,9 +307,8 @@
 Correct example:
 
 ```
-# #![feature(libc)]
 extern crate core;
-extern crate libc as other_name;
+extern crate std as other_name;
 
 fn main() {}
 ```
diff --git a/src/librustc_resolve/lib.rs b/src/librustc_resolve/lib.rs
index ebd2c87..e449fec 100644
--- a/src/librustc_resolve/lib.rs
+++ b/src/librustc_resolve/lib.rs
@@ -3010,6 +3010,7 @@
         // Visit all direct subpatterns of this pattern.
         let outer_pat_id = pat.id;
         pat.walk(&mut |pat| {
+            debug!("resolve_pattern pat={:?} node={:?}", pat, pat.node);
             match pat.node {
                 PatKind::Ident(bmode, ident, ref opt_pat) => {
                     // First try to resolve the identifier as some existing
@@ -3166,6 +3167,7 @@
                  format!("not found in {}", mod_str),
                  item_span)
             };
+
             let code = DiagnosticId::Error(code.into());
             let mut err = this.session.struct_span_err_with_code(base_span, &base_msg, code);
 
@@ -3189,11 +3191,22 @@
                 return (err, Vec::new());
             }
             if is_self_value(path, ns) {
+                debug!("smart_resolve_path_fragment E0424 source:{:?}", source);
+
                 __diagnostic_used!(E0424);
                 err.code(DiagnosticId::Error("E0424".into()));
-                err.span_label(span, format!("`self` value is a keyword \
-                                               only available in \
-                                               methods with `self` parameter"));
+                err.span_label(span, match source {
+                    PathSource::Pat => {
+                        format!("`self` value is a keyword \
+                                and may not be bound to \
+                                variables or shadowed")
+                    }
+                    _ => {
+                        format!("`self` value is a keyword \
+                                only available in methods \
+                                with `self` parameter")
+                    }
+                });
                 return (err, Vec::new());
             }
 
diff --git a/src/librustc_tsan/Cargo.toml b/src/librustc_tsan/Cargo.toml
index baadb64..f061827 100644
--- a/src/librustc_tsan/Cargo.toml
+++ b/src/librustc_tsan/Cargo.toml
@@ -16,4 +16,4 @@
 [dependencies]
 alloc = { path = "../liballoc" }
 core = { path = "../libcore" }
-compiler_builtins = { path = "../rustc/compiler_builtins_shim" }
+compiler_builtins = "0.1.0"
diff --git a/src/librustc_typeck/check/demand.rs b/src/librustc_typeck/check/demand.rs
index f4f6b3d..db4b686 100644
--- a/src/librustc_typeck/check/demand.rs
+++ b/src/librustc_typeck/check/demand.rs
@@ -123,7 +123,7 @@
                         let sole_field_ty = sole_field.ty(self.tcx, substs);
                         if self.can_coerce(expr_ty, sole_field_ty) {
                             let variant_path = self.tcx.item_path_str(variant.did);
-                            Some(variant_path.trim_left_matches("std::prelude::v1::").to_string())
+                            Some(variant_path.trim_start_matches("std::prelude::v1::").to_string())
                         } else {
                             None
                         }
@@ -519,7 +519,7 @@
                 let suffix_suggestion = format!(
                     "{}{}{}{}",
                     if needs_paren { "(" } else { "" },
-                    src.trim_right_matches(&checked_ty.to_string()),
+                    src.trim_end_matches(&checked_ty.to_string()),
                     expected_ty,
                     if needs_paren { ")" } else { "" },
                 );
diff --git a/src/librustc_typeck/check/intrinsic.rs b/src/librustc_typeck/check/intrinsic.rs
index 5c0eef5..a40e56d 100644
--- a/src/librustc_typeck/check/intrinsic.rs
+++ b/src/librustc_typeck/check/intrinsic.rs
@@ -435,7 +435,8 @@
         "simd_insert" => (2, vec![param(0), tcx.types.u32, param(1)], param(0)),
         "simd_extract" => (2, vec![param(0), tcx.types.u32], param(1)),
         "simd_cast" => (2, vec![param(0)], param(1)),
-        "simd_select" => (2, vec![param(0), param(1), param(1)], param(1)),
+        "simd_select" |
+        "simd_select_bitmask" => (2, vec![param(0), param(1), param(1)], param(1)),
         "simd_reduce_all" | "simd_reduce_any" => (1, vec![param(0)], tcx.types.bool),
         "simd_reduce_add_ordered" | "simd_reduce_mul_ordered"
             => (2, vec![param(0), param(1)], param(1)),
diff --git a/src/librustdoc/clean/mod.rs b/src/librustdoc/clean/mod.rs
index 64f66d5..1e33ec8 100644
--- a/src/librustdoc/clean/mod.rs
+++ b/src/librustdoc/clean/mod.rs
@@ -707,8 +707,6 @@
 /// kept separate because of issue #42760.
 #[derive(Clone, RustcEncodable, RustcDecodable, PartialEq, Eq, Debug, Hash)]
 pub enum DocFragment {
-    // FIXME #44229 (misdreavus): sugared and raw doc comments can be brought back together once
-    // hoedown is completely removed from rustdoc.
     /// A doc fragment created from a `///` or `//!` doc comment.
     SugaredDoc(usize, syntax_pos::Span, String),
     /// A doc fragment created from a "raw" `#[doc=""]` attribute.
diff --git a/src/librustdoc/config.rs b/src/librustdoc/config.rs
index f4d05c6..b421f07 100644
--- a/src/librustdoc/config.rs
+++ b/src/librustdoc/config.rs
@@ -20,7 +20,7 @@
 use rustc::session::config::{CodegenOptions, DebuggingOptions, ErrorOutputType, Externs};
 use rustc::session::config::{nightly_options, build_codegen_options, build_debugging_options,
                              get_cmd_lint_options};
-use rustc::session::search_paths::SearchPaths;
+use rustc::session::search_paths::SearchPath;
 use rustc_driver;
 use rustc_target::spec::TargetTriple;
 use syntax::edition::Edition;
@@ -46,7 +46,7 @@
     /// How to format errors and warnings.
     pub error_format: ErrorOutputType,
     /// Library search paths to hand to the compiler.
-    pub libs: SearchPaths,
+    pub libs: Vec<SearchPath>,
     /// The list of external crates to link against.
     pub externs: Externs,
     /// List of `cfg` flags to hand to the compiler. Always includes `rustdoc`.
@@ -295,10 +295,9 @@
         }
         let input = PathBuf::from(&matches.free[0]);
 
-        let mut libs = SearchPaths::new();
-        for s in &matches.opt_strs("L") {
-            libs.add_path(s, error_format);
-        }
+        let libs = matches.opt_strs("L").iter()
+            .map(|s| SearchPath::from_cli_opt(s, error_format))
+            .collect();
         let externs = match parse_externs(&matches) {
             Ok(ex) => ex,
             Err(err) => {
diff --git a/src/librustdoc/core.rs b/src/librustdoc/core.rs
index 047d355..b85342f 100644
--- a/src/librustdoc/core.rs
+++ b/src/librustdoc/core.rs
@@ -51,7 +51,7 @@
 use passes;
 
 pub use rustc::session::config::{Input, Options, CodegenOptions};
-pub use rustc::session::search_paths::SearchPaths;
+pub use rustc::session::search_paths::SearchPath;
 
 pub type ExternalPaths = FxHashMap<DefId, (Vec<String>, clean::TypeKind)>;
 
diff --git a/src/librustdoc/html/layout.rs b/src/librustdoc/html/layout.rs
index 6ce02c3..37ff693 100644
--- a/src/librustdoc/html/layout.rs
+++ b/src/librustdoc/html/layout.rs
@@ -54,6 +54,7 @@
     <link rel=\"stylesheet\" type=\"text/css\" href=\"{root_path}light{suffix}.css\" \
           id=\"themeStyle\">\
     <script src=\"{root_path}storage{suffix}.js\"></script>\
+    <noscript><link rel=\"stylesheet\" href=\"{root_path}noscript{suffix}.css\"></noscript>\
     {css_extension}\
     {favicon}\
     {in_header}\
diff --git a/src/librustdoc/html/markdown.rs b/src/librustdoc/html/markdown.rs
index 00ca4fe..536ea39 100644
--- a/src/librustdoc/html/markdown.rs
+++ b/src/librustdoc/html/markdown.rs
@@ -806,6 +806,10 @@
 }
 
 pub fn plain_summary_line(md: &str) -> String {
+    plain_summary_line_full(md, false)
+}
+
+pub fn plain_summary_line_full(md: &str, limit_length: bool) -> String {
     struct ParserWrapper<'a> {
         inner: Parser<'a>,
         is_in: isize,
@@ -852,7 +856,21 @@
             s.push_str(&t);
         }
     }
-    s
+    if limit_length && s.chars().count() > 60 {
+        let mut len = 0;
+        let mut ret = s.split_whitespace()
+                       .take_while(|p| {
+                           // + 1 for the added character after the word.
+                           len += p.chars().count() + 1;
+                           len < 60
+                       })
+                       .collect::<Vec<_>>()
+                       .join(" ");
+        ret.push('…');
+        ret
+    } else {
+        s
+    }
 }
 
 pub fn markdown_links(md: &str) -> Vec<(String, Option<Range<usize>>)> {
diff --git a/src/librustdoc/html/render.rs b/src/librustdoc/html/render.rs
index 8d7942a..c9f3aa0 100644
--- a/src/librustdoc/html/render.rs
+++ b/src/librustdoc/html/render.rs
@@ -698,7 +698,7 @@
                 ty: item.type_(),
                 name: item.name.clone().unwrap(),
                 path: fqp[..fqp.len() - 1].join("::"),
-                desc: plain_summary_line(item.doc_value()),
+                desc: plain_summary_line_short(item.doc_value()),
                 parent: Some(did),
                 parent_idx: None,
                 search_type: get_index_search_type(&item),
@@ -736,7 +736,7 @@
     }
 
     let crate_doc = krate.module.as_ref().map(|module| {
-        plain_summary_line(module.doc_value())
+        plain_summary_line_short(module.doc_value())
     }).unwrap_or(String::new());
 
     let mut crate_data = BTreeMap::new();
@@ -772,6 +772,9 @@
     write_minify(cx.dst.join(&format!("settings{}.css", cx.shared.resource_suffix)),
                  static_files::SETTINGS_CSS,
                  options.enable_minification)?;
+    write_minify(cx.dst.join(&format!("noscript{}.css", cx.shared.resource_suffix)),
+                 static_files::NOSCRIPT_CSS,
+                 options.enable_minification)?;
 
     // To avoid "light.css" to be overwritten, we'll first run over the received themes and only
     // then we'll run over the "official" styles.
@@ -865,9 +868,8 @@
     }
 
     {
-        let mut data = format!("var resourcesSuffix = \"{}\";\n",
-                               cx.shared.resource_suffix);
-        data.push_str(static_files::STORAGE_JS);
+        let mut data = static_files::STORAGE_JS.to_owned();
+        data.push_str(&format!("var resourcesSuffix = \"{}\";", cx.shared.resource_suffix));
         write_minify(cx.dst.join(&format!("storage{}.js", cx.shared.resource_suffix)),
                      &data,
                      options.enable_minification)?;
@@ -1481,7 +1483,7 @@
                             ty: item.type_(),
                             name: s.to_string(),
                             path: path.join("::"),
-                            desc: plain_summary_line(item.doc_value()),
+                            desc: plain_summary_line_short(item.doc_value()),
                             parent,
                             parent_idx: None,
                             search_type: get_index_search_type(&item),
@@ -1512,7 +1514,8 @@
             clean::FunctionItem(..) | clean::ModuleItem(..) |
             clean::ForeignFunctionItem(..) | clean::ForeignStaticItem(..) |
             clean::ConstantItem(..) | clean::StaticItem(..) |
-            clean::UnionItem(..) | clean::ForeignTypeItem | clean::MacroItem(..)
+            clean::UnionItem(..) | clean::ForeignTypeItem |
+            clean::MacroItem(..) | clean::ProcMacroItem(..)
             if !self.stripped_mod => {
                 // Re-exported items mean that the same id can show up twice
                 // in the rustdoc ast that we're looking at. We know,
@@ -1673,7 +1676,7 @@
                                 ty: item.type_(),
                                 name: item_name.to_string(),
                                 path: path.clone(),
-                                desc: plain_summary_line(item.doc_value()),
+                                desc: plain_summary_line_short(item.doc_value()),
                                 parent: None,
                                 parent_idx: None,
                                 search_type: get_index_search_type(&item),
@@ -2388,7 +2391,13 @@
 #[inline]
 fn plain_summary_line(s: Option<&str>) -> String {
     let line = shorter(s).replace("\n", " ");
-    markdown::plain_summary_line(&line[..])
+    markdown::plain_summary_line_full(&line[..], false)
+}
+
+#[inline]
+fn plain_summary_line_short(s: Option<&str>) -> String {
+    let line = shorter(s).replace("\n", " ");
+    markdown::plain_summary_line_full(&line[..], true)
 }
 
 fn document(w: &mut fmt::Formatter, cx: &Context, item: &clean::Item) -> fmt::Result {
@@ -3006,6 +3015,22 @@
     // Trait documentation
     document(w, cx, it)?;
 
+    fn write_small_section_header(
+        w: &mut fmt::Formatter,
+        id: &str,
+        title: &str,
+        extra_content: &str,
+    ) -> fmt::Result {
+        write!(w, "
+            <h2 id='{0}' class='small-section-header'>\
+              {1}<a href='#{0}' class='anchor'></a>\
+            </h2>{2}", id, title, extra_content)
+    }
+
+    fn write_loading_content(w: &mut fmt::Formatter, extra_content: &str) -> fmt::Result {
+        write!(w, "{}<span class='loading-content'>Loading content...</span>", extra_content)
+    }
+
     fn trait_item(w: &mut fmt::Formatter, cx: &Context, m: &clean::Item, t: &clean::Item)
                   -> fmt::Result {
         let name = m.name.as_ref().unwrap();
@@ -3026,74 +3051,45 @@
     }
 
     if !types.is_empty() {
-        write!(w, "
-            <h2 id='associated-types' class='small-section-header'>
-              Associated Types<a href='#associated-types' class='anchor'></a>
-            </h2>
-            <div class='methods'>
-        ")?;
+        write_small_section_header(w, "associated-types", "Associated Types",
+                                   "<div class='methods'>")?;
         for t in &types {
             trait_item(w, cx, *t, it)?;
         }
-        write!(w, "</div>")?;
+        write_loading_content(w, "</div>")?;
     }
 
     if !consts.is_empty() {
-        write!(w, "
-            <h2 id='associated-const' class='small-section-header'>
-              Associated Constants<a href='#associated-const' class='anchor'></a>
-            </h2>
-            <div class='methods'>
-        ")?;
+        write_small_section_header(w, "associated-const", "Associated Constants",
+                                   "<div class='methods'>")?;
         for t in &consts {
             trait_item(w, cx, *t, it)?;
         }
-        write!(w, "</div>")?;
+        write_loading_content(w, "</div>")?;
     }
 
     // Output the documentation for each function individually
     if !required.is_empty() {
-        write!(w, "
-            <h2 id='required-methods' class='small-section-header'>
-              Required Methods<a href='#required-methods' class='anchor'></a>
-            </h2>
-            <div class='methods'>
-        ")?;
+        write_small_section_header(w, "required-methods", "Required methods",
+                                   "<div class='methods'>")?;
         for m in &required {
             trait_item(w, cx, *m, it)?;
         }
-        write!(w, "</div>")?;
+        write_loading_content(w, "</div>")?;
     }
     if !provided.is_empty() {
-        write!(w, "
-            <h2 id='provided-methods' class='small-section-header'>
-              Provided Methods<a href='#provided-methods' class='anchor'></a>
-            </h2>
-            <div class='methods'>
-        ")?;
+        write_small_section_header(w, "provided-methods", "Provided methods",
+                                   "<div class='methods'>")?;
         for m in &provided {
             trait_item(w, cx, *m, it)?;
         }
-        write!(w, "</div>")?;
+        write_loading_content(w, "</div>")?;
     }
 
     // If there are methods directly on this trait object, render them here.
     render_assoc_items(w, cx, it, it.def_id, AssocItemRender::All)?;
 
     let cache = cache();
-    let impl_header = "\
-        <h2 id='implementors' class='small-section-header'>\
-          Implementors<a href='#implementors' class='anchor'></a>\
-        </h2>\
-        <div class='item-list' id='implementors-list'>\
-    ";
-
-    let synthetic_impl_header = "\
-        <h2 id='synthetic-implementors' class='small-section-header'>\
-          Auto implementors<a href='#synthetic-implementors' class='anchor'></a>\
-        </h2>\
-        <div class='item-list' id='synthetic-implementors-list'>\
-    ";
 
     let mut synthetic_types = Vec::new();
 
@@ -3130,11 +3126,7 @@
         concrete.sort_by(compare_impl);
 
         if !foreign.is_empty() {
-            write!(w, "
-                <h2 id='foreign-impls' class='small-section-header'>
-                  Implementations on Foreign Types<a href='#foreign-impls' class='anchor'></a>
-                </h2>
-            ")?;
+            write_small_section_header(w, "foreign-impls", "Implementations on Foreign Types", "")?;
 
             for implementor in foreign {
                 let assoc_link = AssocItemLink::GotoSource(
@@ -3145,33 +3137,38 @@
                             RenderMode::Normal, implementor.impl_item.stable_since(), false,
                             None)?;
             }
+            write_loading_content(w, "")?;
         }
 
-        write!(w, "{}", impl_header)?;
+        write_small_section_header(w, "implementors", "Implementors",
+                                   "<div class='item-list' id='implementors-list'>")?;
         for implementor in concrete {
             render_implementor(cx, implementor, w, &implementor_dups)?;
         }
-        write!(w, "</div>")?;
+        write_loading_content(w, "</div>")?;
 
         if t.auto {
-            write!(w, "{}", synthetic_impl_header)?;
+            write_small_section_header(w, "synthetic-implementors", "Auto implementors",
+                                       "<div class='item-list' id='synthetic-implementors-list'>")?;
             for implementor in synthetic {
                 synthetic_types.extend(
                     collect_paths_for_type(implementor.inner_impl().for_.clone())
                 );
                 render_implementor(cx, implementor, w, &implementor_dups)?;
             }
-            write!(w, "</div>")?;
+            write_loading_content(w, "</div>")?;
         }
     } else {
         // even without any implementations to write in, we still want the heading and list, so the
         // implementors javascript file pulled in below has somewhere to write the impls into
-        write!(w, "{}", impl_header)?;
-        write!(w, "</div>")?;
+        write_small_section_header(w, "implementors", "Implementors",
+                                   "<div class='item-list' id='implementors-list'>")?;
+        write_loading_content(w, "</div>")?;
 
         if t.auto {
-            write!(w, "{}", synthetic_impl_header)?;
-            write!(w, "</div>")?;
+            write_small_section_header(w, "synthetic-implementors", "Auto implementors",
+                                       "<div class='item-list' id='synthetic-implementors-list'>")?;
+            write_loading_content(w, "</div>")?;
         }
     }
     write!(w, r#"<script type="text/javascript">window.inlined_types=new Set({});</script>"#,
diff --git a/src/librustdoc/html/static/main.js b/src/librustdoc/html/static/main.js
index 1869969..51714c3 100644
--- a/src/librustdoc/html/static/main.js
+++ b/src/librustdoc/html/static/main.js
@@ -30,6 +30,27 @@
     };
 }
 
+if (!DOMTokenList.prototype.add) {
+    DOMTokenList.prototype.add = function(className) {
+        if (className && !hasClass(this, className)) {
+            if (this.className && this.className.length > 0) {
+                this.className += " " + className;
+            } else {
+                this.className = className;
+            }
+        }
+    };
+}
+
+if (!DOMTokenList.prototype.remove) {
+    DOMTokenList.prototype.remove = function(className) {
+        if (className && this.className) {
+            this.className = (" " + this.className + " ").replace(" " + className + " ", " ")
+                                                         .trim();
+        }
+    };
+}
+
 (function() {
     "use strict";
 
@@ -61,7 +82,7 @@
                      "attr",
                      "derive"];
 
-    var search_input = document.getElementsByClassName('search-input')[0];
+    var search_input = document.getElementsByClassName("search-input")[0];
 
     // On the search screen, so you remain on the last tab you opened.
     //
@@ -75,9 +96,9 @@
     var titleBeforeSearch = document.title;
 
     function getPageId() {
-        var id = document.location.href.split('#')[1];
+        var id = document.location.href.split("#")[1];
         if (id) {
-            return id.split('?')[0].split('&')[0];
+            return id.split("?")[0].split("&")[0];
         }
         return null;
     }
@@ -87,9 +108,9 @@
         if (elems) {
             addClass(elems, "show-it");
         }
-        var sidebar = document.getElementsByClassName('sidebar')[0];
+        var sidebar = document.getElementsByClassName("sidebar")[0];
         if (sidebar) {
-            addClass(sidebar, 'mobile');
+            addClass(sidebar, "mobile");
             var filler = document.getElementById("sidebar-filler");
             if (!filler) {
                 var div = document.createElement("div");
@@ -108,13 +129,13 @@
         if (elems) {
             removeClass(elems, "show-it");
         }
-        var sidebar = document.getElementsByClassName('sidebar')[0];
-        removeClass(sidebar, 'mobile');
+        var sidebar = document.getElementsByClassName("sidebar")[0];
+        removeClass(sidebar, "mobile");
         var filler = document.getElementById("sidebar-filler");
         if (filler) {
             filler.remove();
         }
-        document.getElementsByTagName("body")[0].style.marginTop = '';
+        document.getElementsByTagName("body")[0].style.marginTop = "";
         var themePicker = document.getElementsByClassName("theme-picker");
         if (themePicker && themePicker.length > 0) {
             themePicker[0].style.display = null;
@@ -125,8 +146,8 @@
     var TY_PRIMITIVE = itemTypes.indexOf("primitive");
     var TY_KEYWORD = itemTypes.indexOf("keyword");
 
-    onEach(document.getElementsByClassName('js-only'), function(e) {
-        removeClass(e, 'js-only');
+    onEachLazy(document.getElementsByClassName("js-only"), function(e) {
+        removeClass(e, "js-only");
     });
 
     function getQueryStringParams() {
@@ -145,16 +166,19 @@
           window.history && typeof window.history.pushState === "function";
     }
 
+    var main = document.getElementById("main");
+
     function highlightSourceLines(ev) {
         // If we're in mobile mode, we should add the sidebar in any case.
         hideSidebar();
+        var elem;
         var search = document.getElementById("search");
         var i, from, to, match = window.location.hash.match(/^#?(\d+)(?:-(\d+))?$/);
         if (match) {
             from = parseInt(match[1], 10);
             to = Math.min(50000, parseInt(match[2] || match[1], 10));
             from = Math.min(from, to);
-            var elem = document.getElementById(from);
+            elem = document.getElementById(from);
             if (!elem) {
                 return;
             }
@@ -164,22 +188,22 @@
                     x.scrollIntoView();
                 }
             }
-            onEach(document.getElementsByClassName('line-numbers'), function(e) {
-                onEach(e.getElementsByTagName('span'), function(i_e) {
-                    removeClass(i_e, 'line-highlighted');
+            onEachLazy(document.getElementsByClassName("line-numbers"), function(e) {
+                onEachLazy(e.getElementsByTagName("span"), function(i_e) {
+                    removeClass(i_e, "line-highlighted");
                 });
             });
             for (i = from; i <= to; ++i) {
-                addClass(document.getElementById(i), 'line-highlighted');
+                addClass(document.getElementById(i), "line-highlighted");
             }
         } else if (ev !== null && search && !hasClass(search, "hidden") && ev.newURL) {
             addClass(search, "hidden");
-            removeClass(document.getElementById("main"), "hidden");
-            var hash = ev.newURL.slice(ev.newURL.indexOf('#') + 1);
+            removeClass(main, "hidden");
+            var hash = ev.newURL.slice(ev.newURL.indexOf("#") + 1);
             if (browserSupportsHistoryApi()) {
                 history.replaceState(hash, "", "?search=#" + hash);
             }
-            var elem = document.getElementById(hash);
+            elem = document.getElementById(hash);
             if (elem) {
                 elem.scrollIntoView();
             }
@@ -190,7 +214,7 @@
         var elem = document.getElementById(id);
         if (elem && isHidden(elem)) {
             var h3 = elem.parentNode.previousSibling;
-            if (h3 && h3.tagName !== 'H3') {
+            if (h3 && h3.tagName !== "H3") {
                 h3 = h3.previousSibling; // skip div.docblock
             }
 
@@ -236,7 +260,7 @@
                 removeClass(help, "hidden");
                 addClass(document.body, "blur");
             }
-        } else if (!hasClass(help, "hidden")) {
+        } else if (hasClass(help, "hidden") === false) {
             ev.preventDefault();
             addClass(help, "hidden");
             removeClass(document.body, "blur");
@@ -246,12 +270,12 @@
     function handleEscape(ev, help) {
         hideModal();
         var search = document.getElementById("search");
-        if (!hasClass(help, "hidden")) {
+        if (hasClass(help, "hidden") === false) {
             displayHelp(false, ev);
-        } else if (!hasClass(search, "hidden")) {
+        } else if (hasClass(search, "hidden") === false) {
             ev.preventDefault();
             addClass(search, "hidden");
-            removeClass(document.getElementById("main"), "hidden");
+            removeClass(main, "hidden");
             document.title = titleBeforeSearch;
         }
         defocusSearchBar();
@@ -305,26 +329,27 @@
             if (elem && elem.tagName === tagName) {
                 return elem;
             }
-        } while (elem = elem.parentNode);
+            elem = elem.parentNode;
+        } while (elem);
         return null;
     }
 
     document.onkeypress = handleShortcut;
     document.onkeydown = handleShortcut;
     document.onclick = function(ev) {
-        if (hasClass(ev.target, 'collapse-toggle')) {
+        if (hasClass(ev.target, "collapse-toggle")) {
             collapseDocs(ev.target, "toggle");
-        } else if (hasClass(ev.target.parentNode, 'collapse-toggle')) {
+        } else if (hasClass(ev.target.parentNode, "collapse-toggle")) {
             collapseDocs(ev.target.parentNode, "toggle");
-        } else if (ev.target.tagName === 'SPAN' && hasClass(ev.target.parentNode, 'line-numbers')) {
+        } else if (ev.target.tagName === "SPAN" && hasClass(ev.target.parentNode, "line-numbers")) {
             var prev_id = 0;
 
             var set_fragment = function(name) {
                 if (browserSupportsHistoryApi()) {
-                    history.replaceState(null, null, '#' + name);
+                    history.replaceState(null, null, "#" + name);
                     window.hashchange();
                 } else {
-                    location.replace('#' + name);
+                    location.replace("#" + name);
                 }
             };
 
@@ -337,31 +362,31 @@
                     cur_id = tmp;
                 }
 
-                set_fragment(prev_id + '-' + cur_id);
+                set_fragment(prev_id + "-" + cur_id);
             } else {
                 prev_id = cur_id;
 
                 set_fragment(cur_id);
             }
-        } else if (!hasClass(document.getElementById("help"), "hidden")) {
+        } else if (hasClass(document.getElementById("help"), "hidden") === false) {
             addClass(document.getElementById("help"), "hidden");
             removeClass(document.body, "blur");
         } else {
             // Making a collapsed element visible on onhashchange seems
             // too late
-            var a = findParentElement(ev.target, 'A');
+            var a = findParentElement(ev.target, "A");
             if (a && a.hash) {
-                expandSection(a.hash.replace(/^#/, ''));
+                expandSection(a.hash.replace(/^#/, ""));
             }
         }
     };
 
-    var x = document.getElementsByClassName('version-selector');
+    var x = document.getElementsByClassName("version-selector");
     if (x.length > 0) {
         x[0].onchange = function() {
             var i, match,
                 url = document.location.href,
-                stripped = '',
+                stripped = "",
                 len = rootPath.match(/\.\.\//g).length + 1;
 
             for (i = 0; i < len; ++i) {
@@ -372,7 +397,7 @@
                 url = url.substring(0, url.length - match[0].length);
             }
 
-            url += '/' + document.getElementsByClassName('version-selector')[0].value + stripped;
+            url += "/" + document.getElementsByClassName("version-selector")[0].value + stripped;
 
             document.location.href = url;
         };
@@ -428,7 +453,7 @@
         // where you start trying to do a search, and the index loads, and
         // suddenly your search is gone!
         if (search_input.value === "") {
-            search_input.value = params.search || '';
+            search_input.value = params.search || "";
         }
 
         /**
@@ -441,7 +466,8 @@
          */
         function execQuery(query, searchWords, filterCrates) {
             function itemTypeFromName(typename) {
-                for (var i = 0; i < itemTypes.length; ++i) {
+                var length = itemTypes.length;
+                for (var i = 0; i < length; ++i) {
                     if (itemTypes[i] === typename) {
                         return i;
                     }
@@ -455,7 +481,8 @@
                 results = {}, results_in_args = {}, results_returned = {},
                 split = valLower.split("::");
 
-            for (var z = 0; z < split.length; ++z) {
+            var length = split.length;
+            for (var z = 0; z < length; ++z) {
                 if (split[z] === "") {
                     split.splice(z, 1);
                     z -= 1;
@@ -464,7 +491,8 @@
 
             function transformResults(results, isType) {
                 var out = [];
-                for (i = 0; i < results.length; ++i) {
+                var length = results.length;
+                for (var i = 0; i < length; ++i) {
                     if (results[i].id > -1) {
                         var obj = searchIndex[results[i].id];
                         obj.lev = results[i].lev;
@@ -473,7 +501,7 @@
                             obj.displayPath = pathSplitter(res[0]);
                             obj.fullPath = obj.displayPath + obj.name;
                             // To be sure than it some items aren't considered as duplicate.
-                            obj.fullPath += '|' + obj.ty;
+                            obj.fullPath += "|" + obj.ty;
                             obj.href = res[1];
                             out.push(obj);
                             if (out.length >= MAX_RESULTS) {
@@ -493,8 +521,9 @@
                     }
                 }
                 results = ar;
+                var i;
                 var nresults = results.length;
-                for (var i = 0; i < nresults; ++i) {
+                for (i = 0; i < nresults; ++i) {
                     results[i].word = searchWords[results[i].id];
                     results[i].item = searchIndex[results[i].id] || {};
                 }
@@ -552,8 +581,8 @@
                     }
 
                     // sort by description (no description goes later)
-                    a = (aaa.item.desc === '');
-                    b = (bbb.item.desc === '');
+                    a = (aaa.item.desc === "");
+                    b = (bbb.item.desc === "");
                     if (a !== b) { return a - b; }
 
                     // sort by type (later occurrence in `itemTypes` goes later)
@@ -570,7 +599,8 @@
                     return 0;
                 });
 
-                for (var i = 0; i < results.length; ++i) {
+                var length = results.length;
+                for (i = 0; i < length; ++i) {
                     var result = results[i];
 
                     // this validation does not make sense when searching by types
@@ -592,10 +622,10 @@
 
             function extractGenerics(val) {
                 val = val.toLowerCase();
-                if (val.indexOf('<') !== -1) {
-                    var values = val.substring(val.indexOf('<') + 1, val.lastIndexOf('>'));
+                if (val.indexOf("<") !== -1) {
+                    var values = val.substring(val.indexOf("<") + 1, val.lastIndexOf(">"));
                     return {
-                        name: val.substring(0, val.indexOf('<')),
+                        name: val.substring(0, val.indexOf("<")),
                         generics: values.split(/\s*,\s*/),
                     };
                 }
@@ -617,9 +647,11 @@
                         var done = 0;
                         // We need to find the type that matches the most to remove it in order
                         // to move forward.
-                        for (var y = 0; y < val.generics.length; ++y) {
+                        var vlength = val.generics.length;
+                        for (var y = 0; y < vlength; ++y) {
                             var lev = { pos: -1, lev: MAX_LEV_DISTANCE + 1};
-                            for (var x = 0; x < elems.length; ++x) {
+                            var elength = elems.length;
+                            for (var x = 0; x < elength; ++x) {
                                 var tmp_lev = levenshtein(elems[x], val.generics[y]);
                                 if (tmp_lev < lev.lev) {
                                     lev.lev = tmp_lev;
@@ -644,6 +676,7 @@
             // Check for type name and type generics (if any).
             function checkType(obj, val, literalSearch) {
                 var lev_distance = MAX_LEV_DISTANCE + 1;
+                var x;
                 if (obj[NAME] === val.name) {
                     if (literalSearch === true) {
                         if (val.generics && val.generics.length !== 0) {
@@ -651,7 +684,6 @@
                                   obj[GENERICS_DATA].length >= val.generics.length) {
                                 var elems = obj[GENERICS_DATA].slice(0);
                                 var allFound = true;
-                                var x;
 
                                 for (var y = 0; allFound === true && y < val.generics.length; ++y) {
                                     allFound = false;
@@ -685,7 +717,8 @@
                 // Names didn't match so let's check if one of the generic types could.
                 if (literalSearch === true) {
                      if (obj.length > GENERICS_DATA && obj[GENERICS_DATA].length > 0) {
-                        for (var x = 0; x < obj[GENERICS_DATA].length; ++x) {
+                        var length = obj[GENERICS_DATA].length;
+                        for (x = 0; x < length; ++x) {
                             if (obj[GENERICS_DATA][x] === val.name) {
                                 return true;
                             }
@@ -693,13 +726,13 @@
                     }
                     return false;
                 }
-                var lev_distance = Math.min(levenshtein(obj[NAME], val.name),
-                                            lev_distance);
+                lev_distance = Math.min(levenshtein(obj[NAME], val.name), lev_distance);
                 if (lev_distance <= MAX_LEV_DISTANCE) {
                     lev_distance = Math.min(checkGenerics(obj, val), lev_distance);
                 } else if (obj.length > GENERICS_DATA && obj[GENERICS_DATA].length > 0) {
                     // We can check if the type we're looking for is inside the generics!
-                    for (var x = 0; x < obj[GENERICS_DATA].length; ++x) {
+                    var olength = obj[GENERICS_DATA].length;
+                    for (x = 0; x < olength; ++x) {
                         lev_distance = Math.min(levenshtein(obj[GENERICS_DATA][x], val.name),
                                                 lev_distance);
                     }
@@ -714,7 +747,8 @@
 
                 if (obj && obj.type && obj.type[INPUTS_DATA] &&
                       obj.type[INPUTS_DATA].length > 0) {
-                    for (var i = 0; i < obj.type[INPUTS_DATA].length; i++) {
+                    var length = obj.type[INPUTS_DATA].length;
+                    for (var i = 0; i < length; i++) {
                         var tmp = checkType(obj.type[INPUTS_DATA][i], val, literalSearch);
                         if (literalSearch === true && tmp === true) {
                             return true;
@@ -755,16 +789,18 @@
                     path.push(ty.parent.name.toLowerCase());
                 }
 
-                if (contains.length > path.length) {
+                var length = path.length;
+                var clength = contains.length;
+                if (clength > length) {
                     return MAX_LEV_DISTANCE + 1;
                 }
-                for (var i = 0; i < path.length; ++i) {
-                    if (i + contains.length > path.length) {
+                for (var i = 0; i < length; ++i) {
+                    if (i + clength > length) {
                         break;
                     }
                     var lev_total = 0;
                     var aborted = false;
-                    for (var x = 0; x < contains.length; ++x) {
+                    for (var x = 0; x < clength; ++x) {
                         var lev = levenshtein(path[i + x], contains[x]);
                         if (lev > MAX_LEV_DISTANCE) {
                             aborted = true;
@@ -773,7 +809,7 @@
                         lev_total += lev;
                     }
                     if (aborted === false) {
-                        ret_lev = Math.min(ret_lev, Math.round(lev_total / contains.length));
+                        ret_lev = Math.min(ret_lev, Math.round(lev_total / clength));
                     }
                 }
                 return ret_lev;
@@ -810,18 +846,23 @@
 
             // quoted values mean literal search
             var nSearchWords = searchWords.length;
+            var i;
+            var ty;
+            var fullId;
+            var returned;
+            var in_args;
             if ((val.charAt(0) === "\"" || val.charAt(0) === "'") &&
                 val.charAt(val.length - 1) === val.charAt(0))
             {
                 val = extractGenerics(val.substr(1, val.length - 2));
-                for (var i = 0; i < nSearchWords; ++i) {
+                for (i = 0; i < nSearchWords; ++i) {
                     if (filterCrates !== undefined && searchIndex[i].crate !== filterCrates) {
                         continue;
                     }
-                    var in_args = findArg(searchIndex[i], val, true);
-                    var returned = checkReturned(searchIndex[i], val, true);
-                    var ty = searchIndex[i];
-                    var fullId = generateId(ty);
+                    in_args = findArg(searchIndex[i], val, true);
+                    returned = checkReturned(searchIndex[i], val, true);
+                    ty = searchIndex[i];
+                    fullId = generateId(ty);
 
                     if (searchWords[i] === val.name) {
                         // filter type: ... queries
@@ -866,27 +907,27 @@
                 var input = parts[0];
                 // sort inputs so that order does not matter
                 var inputs = input.split(",").map(trimmer).sort();
-                for (var i = 0; i < inputs.length; ++i) {
+                for (i = 0; i < inputs.length; ++i) {
                     inputs[i] = extractGenerics(inputs[i]);
                 }
                 var output = extractGenerics(parts[1]);
 
-                for (var i = 0; i < nSearchWords; ++i) {
+                for (i = 0; i < nSearchWords; ++i) {
                     if (filterCrates !== undefined && searchIndex[i].crate !== filterCrates) {
                         continue;
                     }
                     var type = searchIndex[i].type;
-                    var ty = searchIndex[i];
+                    ty = searchIndex[i];
                     if (!type) {
                         continue;
                     }
-                    var fullId = generateId(ty);
+                    fullId = generateId(ty);
 
                     // allow searching for void (no output) functions as well
                     var typeOutput = type.length > OUTPUT_DATA ? type[OUTPUT_DATA].name : "";
-                    var returned = checkReturned(ty, output, true);
+                    returned = checkReturned(ty, output, true);
                     if (output.name === "*" || returned === true) {
-                        var in_args = false;
+                        in_args = false;
                         var module = false;
 
                         if (input === "*") {
@@ -946,14 +987,16 @@
                 var contains = paths.slice(0, paths.length > 1 ? paths.length - 1 : 1);
 
                 for (j = 0; j < nSearchWords; ++j) {
-                    var ty = searchIndex[j];
+                    var lev;
+                    var lev_distance;
+                    ty = searchIndex[j];
                     if (!ty || (filterCrates !== undefined && ty.crate !== filterCrates)) {
                         continue;
                     }
                     var lev_distance;
                     var lev_add = 0;
                     if (paths.length > 1) {
-                        var lev = checkPath(contains, paths[paths.length - 1], ty);
+                        lev = checkPath(contains, paths[paths.length - 1], ty);
                         if (lev > MAX_LEV_DISTANCE) {
                             continue;
                         } else if (lev > 0) {
@@ -961,12 +1004,12 @@
                         }
                     }
 
-                    var returned = MAX_LEV_DISTANCE + 1;
-                    var in_args = MAX_LEV_DISTANCE + 1;
+                    returned = MAX_LEV_DISTANCE + 1;
+                    in_args = MAX_LEV_DISTANCE + 1;
                     var index = -1;
                     // we want lev results to go lower than others
-                    var lev = MAX_LEV_DISTANCE + 1;
-                    var fullId = generateId(ty);
+                    lev = MAX_LEV_DISTANCE + 1;
+                    fullId = generateId(ty);
 
                     if (searchWords[j].indexOf(split[i]) > -1 ||
                         searchWords[j].indexOf(val) > -1 ||
@@ -1042,14 +1085,14 @@
             }
 
             var ret = {
-                'in_args': sortResults(results_in_args, true),
-                'returned': sortResults(results_returned, true),
-                'others': sortResults(results),
+                "in_args": sortResults(results_in_args, true),
+                "returned": sortResults(results_returned, true),
+                "others": sortResults(results),
             };
             if (ALIASES && ALIASES[window.currentCrate] &&
                     ALIASES[window.currentCrate][query.raw]) {
                 var aliases = ALIASES[window.currentCrate][query.raw];
-                for (var i = 0; i < aliases.length; ++i) {
+                for (i = 0; i < aliases.length; ++i) {
                     aliases[i].is_alias = true;
                     aliases[i].alias = query.raw;
                     aliases[i].path = aliases[i].p;
@@ -1057,9 +1100,9 @@
                     aliases[i].displayPath = pathSplitter(res[0]);
                     aliases[i].fullPath = aliases[i].displayPath + aliases[i].name;
                     aliases[i].href = res[1];
-                    ret['others'].unshift(aliases[i]);
-                    if (ret['others'].length > MAX_RESULTS) {
-                        ret['others'].pop();
+                    ret.others.unshift(aliases[i]);
+                    if (ret.others.length > MAX_RESULTS) {
+                        ret.others.pop();
                     }
                 }
             }
@@ -1106,7 +1149,7 @@
 
             matches = query.match(/^(fn|mod|struct|enum|trait|type|const|macro)\s*:\s*/i);
             if (matches) {
-                type = matches[1].replace(/^const$/, 'constant');
+                type = matches[1].replace(/^const$/, "constant");
                 query = query.substring(matches[0].length);
             }
 
@@ -1124,38 +1167,38 @@
             var click_func = function(e) {
                 var el = e.target;
                 // to retrieve the real "owner" of the event.
-                while (el.tagName !== 'TR') {
+                while (el.tagName !== "TR") {
                     el = el.parentNode;
                 }
-                var dst = e.target.getElementsByTagName('a');
+                var dst = e.target.getElementsByTagName("a");
                 if (dst.length < 1) {
                     return;
                 }
                 dst = dst[0];
                 if (window.location.pathname === dst.pathname) {
-                    addClass(document.getElementById('search'), 'hidden');
-                    removeClass(document.getElementById('main'), 'hidden');
+                    addClass(document.getElementById("search"), "hidden");
+                    removeClass(main, "hidden");
                     document.location.href = dst.href;
                 }
             };
             var mouseover_func = function(e) {
                 var el = e.target;
                 // to retrieve the real "owner" of the event.
-                while (el.tagName !== 'TR') {
+                while (el.tagName !== "TR") {
                     el = el.parentNode;
                 }
                 clearTimeout(hoverTimeout);
                 hoverTimeout = setTimeout(function() {
-                    onEach(document.getElementsByClassName('search-results'), function(e) {
-                        onEach(e.getElementsByClassName('result'), function(i_e) {
-                            removeClass(i_e, 'highlighted');
+                    onEachLazy(document.getElementsByClassName("search-results"), function(e) {
+                        onEachLazy(e.getElementsByClassName("result"), function(i_e) {
+                            removeClass(i_e, "highlighted");
                         });
                     });
-                    addClass(el, 'highlighted');
+                    addClass(el, "highlighted");
                 }, 20);
             };
-            onEach(document.getElementsByClassName('search-results'), function(e) {
-                onEach(e.getElementsByClassName('result'), function(i_e) {
+            onEachLazy(document.getElementsByClassName("search-results"), function(e) {
+                onEachLazy(e.getElementsByClassName("result"), function(i_e) {
                     i_e.onclick = click_func;
                     i_e.onmouseover = mouseover_func;
                 });
@@ -1167,8 +1210,8 @@
                 var actives = [[], [], []];
                 // "current" is used to know which tab we're looking into.
                 var current = 0;
-                onEach(document.getElementsByClassName('search-results'), function(e) {
-                    onEach(e.getElementsByClassName('highlighted'), function(e) {
+                onEachLazy(document.getElementsByClassName("search-results"), function(e) {
+                    onEachLazy(e.getElementsByClassName("highlighted"), function(e) {
                         actives[current].push(e);
                     });
                     current += 1;
@@ -1180,25 +1223,25 @@
                         return;
                     }
 
-                    addClass(actives[currentTab][0].previousElementSibling, 'highlighted');
-                    removeClass(actives[currentTab][0], 'highlighted');
+                    addClass(actives[currentTab][0].previousElementSibling, "highlighted");
+                    removeClass(actives[currentTab][0], "highlighted");
                 } else if (e.which === 40) { // down
                     if (!actives[currentTab].length) {
-                        var results = document.getElementsByClassName('search-results');
+                        var results = document.getElementsByClassName("search-results");
                         if (results.length > 0) {
-                            var res = results[currentTab].getElementsByClassName('result');
+                            var res = results[currentTab].getElementsByClassName("result");
                             if (res.length > 0) {
-                                addClass(res[0], 'highlighted');
+                                addClass(res[0], "highlighted");
                             }
                         }
                     } else if (actives[currentTab][0].nextElementSibling) {
-                        addClass(actives[currentTab][0].nextElementSibling, 'highlighted');
-                        removeClass(actives[currentTab][0], 'highlighted');
+                        addClass(actives[currentTab][0].nextElementSibling, "highlighted");
+                        removeClass(actives[currentTab][0], "highlighted");
                     }
                 } else if (e.which === 13) { // return
                     if (actives[currentTab].length) {
                         document.location.href =
-                            actives[currentTab][0].getElementsByTagName('a')[0].href;
+                            actives[currentTab][0].getElementsByTagName("a")[0].href;
                     }
                 } else if (e.which === 9) { // tab
                     if (e.shiftKey) {
@@ -1210,11 +1253,11 @@
                 } else if (e.which === 16) { // shift
                     // Does nothing, it's just to avoid losing "focus" on the highlighted element.
                 } else if (e.which === 27) { // escape
-                    removeClass(actives[currentTab][0], 'highlighted');
-                    search_input.value = '';
+                    removeClass(actives[currentTab][0], "highlighted");
+                    search_input.value = "";
                     defocusSearchBar();
                 } else if (actives[currentTab].length > 0) {
-                    removeClass(actives[currentTab][0], 'highlighted');
+                    removeClass(actives[currentTab][0], "highlighted");
                 }
             };
         }
@@ -1225,46 +1268,46 @@
             var type = itemTypes[item.ty];
             var name = item.name;
 
-            if (type === 'mod') {
-                displayPath = item.path + '::';
-                href = rootPath + item.path.replace(/::/g, '/') + '/' +
-                       name + '/index.html';
+            if (type === "mod") {
+                displayPath = item.path + "::";
+                href = rootPath + item.path.replace(/::/g, "/") + "/" +
+                       name + "/index.html";
             } else if (type === "primitive" || type === "keyword") {
                 displayPath = "";
-                href = rootPath + item.path.replace(/::/g, '/') +
-                       '/' + type + '.' + name + '.html';
+                href = rootPath + item.path.replace(/::/g, "/") +
+                       "/" + type + "." + name + ".html";
             } else if (type === "externcrate") {
                 displayPath = "";
-                href = rootPath + name + '/index.html';
+                href = rootPath + name + "/index.html";
             } else if (item.parent !== undefined) {
                 var myparent = item.parent;
-                var anchor = '#' + type + '.' + name;
+                var anchor = "#" + type + "." + name;
                 var parentType = itemTypes[myparent.ty];
                 if (parentType === "primitive") {
-                    displayPath = myparent.name + '::';
+                    displayPath = myparent.name + "::";
                 } else {
-                    displayPath = item.path + '::' + myparent.name + '::';
+                    displayPath = item.path + "::" + myparent.name + "::";
                 }
-                href = rootPath + item.path.replace(/::/g, '/') +
-                       '/' + parentType +
-                       '.' + myparent.name +
-                       '.html' + anchor;
+                href = rootPath + item.path.replace(/::/g, "/") +
+                       "/" + parentType +
+                       "." + myparent.name +
+                       ".html" + anchor;
             } else {
-                displayPath = item.path + '::';
-                href = rootPath + item.path.replace(/::/g, '/') +
-                       '/' + type + '.' + name + '.html';
+                displayPath = item.path + "::";
+                href = rootPath + item.path.replace(/::/g, "/") +
+                       "/" + type + "." + name + ".html";
             }
             return [displayPath, href];
         }
 
         function escape(content) {
-            var h1 = document.createElement('h1');
+            var h1 = document.createElement("h1");
             h1.textContent = content;
             return h1.innerHTML;
         }
 
         function pathSplitter(path) {
-            var tmp = '<span>' + path.replace(/::/g, '::</span><span>');
+            var tmp = "<span>" + path.replace(/::/g, "::</span><span>");
             if (tmp.endsWith("<span>")) {
                 return tmp.slice(0, tmp.length - 6);
             }
@@ -1272,16 +1315,16 @@
         }
 
         function addTab(array, query, display) {
-            var extraStyle = '';
+            var extraStyle = "";
             if (display === false) {
-                extraStyle = ' style="display: none;"';
+                extraStyle = " style=\"display: none;\"";
             }
 
-            var output = '';
+            var output = "";
             var duplicates = {};
             var length = 0;
             if (array.length > 0) {
-                output = '<table class="search-results"' + extraStyle + '>';
+                output = "<table class=\"search-results\"" + extraStyle + ">";
 
                 array.forEach(function(item) {
                     var name, type;
@@ -1297,50 +1340,50 @@
                     }
                     length += 1;
 
-                    output += '<tr class="' + type + ' result"><td>' +
-                              '<a href="' + item.href + '">' +
+                    output += "<tr class=\"" + type + " result\"><td>" +
+                              "<a href=\"" + item.href + "\">" +
                               (item.is_alias === true ?
-                               ('<span class="alias"><b>' + item.alias + ' </b></span><span ' +
-                                  'class="grey"><i>&nbsp;- see&nbsp;</i></span>') : '') +
-                              item.displayPath + '<span class="' + type + '">' +
-                              name + '</span></a></td><td>' +
-                              '<a href="' + item.href + '">' +
-                              '<span class="desc">' + escape(item.desc) +
-                              '&nbsp;</span></a></td></tr>';
+                               ("<span class=\"alias\"><b>" + item.alias + " </b></span><span " +
+                                  "class=\"grey\"><i>&nbsp;- see&nbsp;</i></span>") : "") +
+                              item.displayPath + "<span class=\"" + type + "\">" +
+                              name + "</span></a></td><td>" +
+                              "<a href=\"" + item.href + "\">" +
+                              "<span class=\"desc\">" + escape(item.desc) +
+                              "&nbsp;</span></a></td></tr>";
                 });
-                output += '</table>';
+                output += "</table>";
             } else {
-                output = '<div class="search-failed"' + extraStyle + '>No results :(<br/>' +
-                    'Try on <a href="https://duckduckgo.com/?q=' +
-                    encodeURIComponent('rust ' + query.query) +
-                    '">DuckDuckGo</a>?<br/><br/>' +
-                    'Or try looking in one of these:<ul><li>The <a ' +
-                    'href="https://doc.rust-lang.org/reference/index.html">Rust Reference</a> for' +
-                    ' technical details about the language.</li><li><a ' +
-                    'href="https://doc.rust-lang.org/rust-by-example/index.html">Rust By Example' +
-                    '</a> for expository code examples.</a></li><li>The <a ' +
-                    'href="https://doc.rust-lang.org/book/index.html">Rust Book</a> for ' +
-                    'introductions to language features and the language itself.</li><li><a ' +
-                    'href="https://docs.rs">Docs.rs</a> for documentation of crates released on ' +
-                    '<a href="https://crates.io/">crates.io</a>.</li></ul></div>';
+                output = "<div class=\"search-failed\"" + extraStyle + ">No results :(<br/>" +
+                    "Try on <a href=\"https://duckduckgo.com/?q=" +
+                    encodeURIComponent("rust " + query.query) +
+                    "\">DuckDuckGo</a>?<br/><br/>" +
+                    "Or try looking in one of these:<ul><li>The <a " +
+                    "href=\"https://doc.rust-lang.org/reference/index.html\">Rust Reference</a> " +
+                    " for technical details about the language.</li><li><a " +
+                    "href=\"https://doc.rust-lang.org/rust-by-example/index.html\">Rust By " +
+                    "Example</a> for expository code examples.</a></li><li>The <a " +
+                    "href=\"https://doc.rust-lang.org/book/index.html\">Rust Book</a> for " +
+                    "introductions to language features and the language itself.</li><li><a " +
+                    "href=\"https://docs.rs\">Docs.rs</a> for documentation of crates released on" +
+                    " <a href=\"https://crates.io/\">crates.io</a>.</li></ul></div>";
             }
             return [output, length];
         }
 
         function makeTabHeader(tabNb, text, nbElems) {
             if (currentTab === tabNb) {
-                return '<div class="selected">' + text +
-                       ' <div class="count">(' + nbElems + ')</div></div>';
+                return "<div class=\"selected\">" + text +
+                       " <div class=\"count\">(" + nbElems + ")</div></div>";
             }
-            return '<div>' + text + ' <div class="count">(' + nbElems + ')</div></div>';
+            return "<div>" + text + " <div class=\"count\">(" + nbElems + ")</div></div>";
         }
 
-        function showResults(results, filterCrates) {
-            if (results['others'].length === 1 &&
-                getCurrentValue('rustdoc-go-to-only-result') === "true") {
-                var elem = document.createElement('a');
-                elem.href = results['others'][0].href;
-                elem.style.display = 'none';
+        function showResults(results) {
+            if (results.others.length === 1 &&
+                getCurrentValue("rustdoc-go-to-only-result") === "true") {
+                var elem = document.createElement("a");
+                elem.href = results.others[0].href;
+                elem.style.display = "none";
                 // For firefox, we need the element to be in the DOM so it can be clicked.
                 document.body.appendChild(elem);
                 elem.click();
@@ -1349,39 +1392,34 @@
 
             currentResults = query.id;
 
-            var ret_others = addTab(results['others'], query);
-            var ret_in_args = addTab(results['in_args'], query, false);
-            var ret_returned = addTab(results['returned'], query, false);
+            var ret_others = addTab(results.others, query);
+            var ret_in_args = addTab(results.in_args, query, false);
+            var ret_returned = addTab(results.returned, query, false);
 
-            var filter = "";
-            if (filterCrates !== undefined) {
-                filter = " (in <b>" + filterCrates + "</b> crate)";
-            }
-
-            var output = '<h1>Results for ' + escape(query.query) +
-                (query.type ? ' (type: ' + escape(query.type) + ')' : '') + filter + '</h1>' +
-                '<div id="titles">' +
+            var output = "<h1>Results for " + escape(query.query) +
+                (query.type ? " (type: " + escape(query.type) + ")" : "") + "</h1>" +
+                "<div id=\"titles\">" +
                 makeTabHeader(0, "In Names", ret_others[1]) +
                 makeTabHeader(1, "In Parameters", ret_in_args[1]) +
                 makeTabHeader(2, "In Return Types", ret_returned[1]) +
-                '</div><div id="results">' +
-                ret_others[0] + ret_in_args[0] + ret_returned[0] + '</div>';
+                "</div><div id=\"results\">" +
+                ret_others[0] + ret_in_args[0] + ret_returned[0] + "</div>";
 
-            addClass(document.getElementById('main'), 'hidden');
-            var search = document.getElementById('search');
-            removeClass(search, 'hidden');
+            addClass(main, "hidden");
+            var search = document.getElementById("search");
+            removeClass(search, "hidden");
             search.innerHTML = output;
-            var tds = search.getElementsByTagName('td');
+            var tds = search.getElementsByTagName("td");
             var td_width = 0;
             if (tds.length > 0) {
                 td_width = tds[0].offsetWidth;
             }
             var width = search.offsetWidth - 40 - td_width;
-            onEach(search.getElementsByClassName('desc'), function(e) {
-                e.style.width = width + 'px';
+            onEachLazy(search.getElementsByClassName("desc"), function(e) {
+                e.style.width = width + "px";
             });
             initSearchNav();
-            var elems = document.getElementById('titles').childNodes;
+            var elems = document.getElementById("titles").childNodes;
             elems[0].onclick = function() { printTab(0); };
             elems[1].onclick = function() { printTab(1); };
             elems[2].onclick = function() { printTab(2); };
@@ -1389,74 +1427,74 @@
         }
 
         function execSearch(query, searchWords, filterCrates) {
+            function getSmallest(arrays, positions, notDuplicates) {
+                var start = null;
+
+                for (var it = 0; it < positions.length; ++it) {
+                    if (arrays[it].length > positions[it] &&
+                        (start === null || start > arrays[it][positions[it]].lev) &&
+                        !notDuplicates[arrays[it][positions[it]].fullPath]) {
+                        start = arrays[it][positions[it]].lev;
+                    }
+                }
+                return start;
+            }
+
+            function mergeArrays(arrays) {
+                var ret = [];
+                var positions = [];
+                var notDuplicates = {};
+
+                for (var x = 0; x < arrays.length; ++x) {
+                    positions.push(0);
+                }
+                while (ret.length < MAX_RESULTS) {
+                    var smallest = getSmallest(arrays, positions, notDuplicates);
+
+                    if (smallest === null) {
+                        break;
+                    }
+                    for (x = 0; x < arrays.length && ret.length < MAX_RESULTS; ++x) {
+                        if (arrays[x].length > positions[x] &&
+                                arrays[x][positions[x]].lev === smallest &&
+                                !notDuplicates[arrays[x][positions[x]].fullPath]) {
+                            ret.push(arrays[x][positions[x]]);
+                            notDuplicates[arrays[x][positions[x]].fullPath] = true;
+                            positions[x] += 1;
+                        }
+                    }
+                }
+                return ret;
+            }
+
             var queries = query.raw.split(",");
             var results = {
-                'in_args': [],
-                'returned': [],
-                'others': [],
+                "in_args": [],
+                "returned": [],
+                "others": [],
             };
 
             for (var i = 0; i < queries.length; ++i) {
-                var query = queries[i].trim();
+                query = queries[i].trim();
                 if (query.length !== 0) {
                     var tmp = execQuery(getQuery(query), searchWords, filterCrates);
 
-                    results['in_args'].push(tmp['in_args']);
-                    results['returned'].push(tmp['returned']);
-                    results['others'].push(tmp['others']);
+                    results.in_args.push(tmp.in_args);
+                    results.returned.push(tmp.returned);
+                    results.others.push(tmp.others);
                 }
             }
             if (queries.length > 1) {
-                function getSmallest(arrays, positions, notDuplicates) {
-                    var start = null;
-
-                    for (var it = 0; it < positions.length; ++it) {
-                        if (arrays[it].length > positions[it] &&
-                            (start === null || start > arrays[it][positions[it]].lev) &&
-                            !notDuplicates[arrays[it][positions[it]].fullPath]) {
-                            start = arrays[it][positions[it]].lev;
-                        }
-                    }
-                    return start;
-                }
-
-                function mergeArrays(arrays) {
-                    var ret = [];
-                    var positions = [];
-                    var notDuplicates = {};
-
-                    for (var x = 0; x < arrays.length; ++x) {
-                        positions.push(0);
-                    }
-                    while (ret.length < MAX_RESULTS) {
-                        var smallest = getSmallest(arrays, positions, notDuplicates);
-
-                        if (smallest === null) {
-                            break;
-                        }
-                        for (x = 0; x < arrays.length && ret.length < MAX_RESULTS; ++x) {
-                            if (arrays[x].length > positions[x] &&
-                                    arrays[x][positions[x]].lev === smallest &&
-                                    !notDuplicates[arrays[x][positions[x]].fullPath]) {
-                                ret.push(arrays[x][positions[x]]);
-                                notDuplicates[arrays[x][positions[x]].fullPath] = true;
-                                positions[x] += 1;
-                            }
-                        }
-                    }
-                    return ret;
-                }
-
                 return {
-                    'in_args': mergeArrays(results['in_args']),
-                    'returned': mergeArrays(results['returned']),
-                    'others': mergeArrays(results['others']),
+                    "in_args": mergeArrays(results.in_args),
+                    "returned": mergeArrays(results.returned),
+                    "others": mergeArrays(results.others),
                 };
             } else {
                 return {
-                    'in_args': results['in_args'][0],
-                    'returned': results['returned'][0],
-                    'others': results['others'][0],
+                    "in_args": results.in_args[0],
+                    "returned": results.returned[0],
+                    "others": results.others[0],
                 };
             }
         }
@@ -1508,6 +1546,8 @@
         function buildIndex(rawSearchIndex) {
             searchIndex = [];
             var searchWords = [];
+            var i;
+
             for (var crate in rawSearchIndex) {
                 if (!rawSearchIndex.hasOwnProperty(crate)) { continue; }
 
@@ -1534,7 +1574,7 @@
 
                 // convert `paths` into an object form
                 var len = paths.length;
-                for (var i = 0; i < len; ++i) {
+                for (i = 0; i < len; ++i) {
                     paths[i] = {ty: paths[i][0], name: paths[i][1]};
                 }
 
@@ -1545,9 +1585,9 @@
                 // operation that is cached for the life of the page state so that
                 // all other search operations have access to this cached data for
                 // faster analysis operations
-                var len = items.length;
+                len = items.length;
                 var lastPath = "";
-                for (var i = 0; i < len; ++i) {
+                for (i = 0; i < len; ++i) {
                     var rawRow = items[i];
                     var row = {crate: crate, ty: rawRow[0], name: rawRow[1],
                                path: rawRow[2] || lastPath, desc: rawRow[3],
@@ -1573,13 +1613,12 @@
                     if (browserSupportsHistoryApi()) {
                         history.replaceState("", "std - Rust", "?search=");
                     }
-                    var main = document.getElementById('main');
-                    if (hasClass(main, 'content')) {
-                        removeClass(main, 'hidden');
+                    if (hasClass(main, "content")) {
+                        removeClass(main, "hidden");
                     }
-                    var search_c = document.getElementById('search');
-                    if (hasClass(search_c, 'content')) {
-                        addClass(search_c, 'hidden');
+                    var search_c = document.getElementById("search");
+                    if (hasClass(search_c, "content")) {
+                        addClass(search_c, "hidden");
                     }
                 } else {
                     searchTimeout = setTimeout(search, 500);
@@ -1620,13 +1659,12 @@
                     // When browsing back from search results the main page
                     // visibility must be reset.
                     if (!params.search) {
-                        var main = document.getElementById('main');
-                        if (hasClass(main, 'content')) {
-                            removeClass(main, 'hidden');
+                        if (hasClass(main, "content")) {
+                            removeClass(main, "hidden");
                         }
-                        var search_c = document.getElementById('search');
-                        if (hasClass(search_c, 'content')) {
-                            addClass(search_c, 'hidden');
+                        var search_c = document.getElementById("search");
+                        if (hasClass(search_c, "content")) {
+                            addClass(search_c, "hidden");
                         }
                     }
                     // Revert to the previous title manually since the History
@@ -1643,9 +1681,9 @@
                     if (params.search) {
                         search_input.value = params.search;
                     } else {
-                        search_input.value = '';
+                        search_input.value = "";
                     }
-                    // Some browsers fire 'onpopstate' for every page load
+                    // Some browsers fire "onpopstate" for every page load
                     // (Chrome), while others fire the event only when actually
                     // popping a state (Firefox), which is why search() is
                     // called both here and at the end of the startSearch()
@@ -1660,13 +1698,13 @@
         startSearch();
 
         // Draw a convenient sidebar of known crates if we have a listing
-        if (rootPath === '../' || rootPath === "./") {
-            var sidebar = document.getElementsByClassName('sidebar-elems')[0];
+        if (rootPath === "../" || rootPath === "./") {
+            var sidebar = document.getElementsByClassName("sidebar-elems")[0];
             if (sidebar) {
-                var div = document.createElement('div');
-                div.className = 'block crate';
-                div.innerHTML = '<h3>Crates</h3>';
-                var ul = document.createElement('ul');
+                var div = document.createElement("div");
+                div.className = "block crate";
+                div.innerHTML = "<h3>Crates</h3>";
+                var ul = document.createElement("ul");
                 div.appendChild(ul);
 
                 var crates = [];
@@ -1678,17 +1716,17 @@
                 }
                 crates.sort();
                 for (var i = 0; i < crates.length; ++i) {
-                    var klass = 'crate';
+                    var klass = "crate";
                     if (rootPath !== "./" && crates[i] === window.currentCrate) {
-                        klass += ' current';
+                        klass += " current";
                     }
-                    var link = document.createElement('a');
-                    link.href = rootPath + crates[i] + '/index.html';
+                    var link = document.createElement("a");
+                    link.href = rootPath + crates[i] + "/index.html";
                     link.title = rawSearchIndex[crates[i]].doc;
                     link.className = klass;
                     link.textContent = crates[i];
 
-                    var li = document.createElement('li');
+                    var li = document.createElement("li");
                     li.appendChild(link);
                     ul.appendChild(li);
                 }
@@ -1701,41 +1739,44 @@
 
     // delayed sidebar rendering.
     function initSidebarItems(items) {
-        var sidebar = document.getElementsByClassName('sidebar-elems')[0];
+        var sidebar = document.getElementsByClassName("sidebar-elems")[0];
         var current = window.sidebarCurrent;
 
         function block(shortty, longty) {
             var filtered = items[shortty];
-            if (!filtered) { return; }
+            if (!filtered) {
+                return;
+            }
 
-            var div = document.createElement('div');
-            div.className = 'block ' + shortty;
-            var h3 = document.createElement('h3');
+            var div = document.createElement("div");
+            div.className = "block " + shortty;
+            var h3 = document.createElement("h3");
             h3.textContent = longty;
             div.appendChild(h3);
-            var ul = document.createElement('ul');
+            var ul = document.createElement("ul");
 
-            for (var i = 0; i < filtered.length; ++i) {
+            var length = filtered.length;
+            for (var i = 0; i < length; ++i) {
                 var item = filtered[i];
                 var name = item[0];
                 var desc = item[1]; // can be null
 
                 var klass = shortty;
                 if (name === current.name && shortty === current.ty) {
-                    klass += ' current';
+                    klass += " current";
                 }
                 var path;
-                if (shortty === 'mod') {
-                    path = name + '/index.html';
+                if (shortty === "mod") {
+                    path = name + "/index.html";
                 } else {
-                    path = shortty + '.' + name + '.html';
+                    path = shortty + "." + name + ".html";
                 }
-                var link = document.createElement('a');
+                var link = document.createElement("a");
                 link.href = current.relpath + path;
                 link.title = desc;
                 link.className = klass;
                 link.textContent = name;
-                var li = document.createElement('li');
+                var li = document.createElement("li");
                 li.appendChild(link);
                 ul.appendChild(li);
             }
@@ -1763,22 +1804,25 @@
     window.initSidebarItems = initSidebarItems;
 
     window.register_implementors = function(imp) {
-        var implementors = document.getElementById('implementors-list');
-        var synthetic_implementors = document.getElementById('synthetic-implementors-list');
+        var implementors = document.getElementById("implementors-list");
+        var synthetic_implementors = document.getElementById("synthetic-implementors-list");
 
         var libs = Object.getOwnPropertyNames(imp);
-        for (var i = 0; i < libs.length; ++i) {
+        var llength = libs.length;
+        for (var i = 0; i < llength; ++i) {
             if (libs[i] === currentCrate) { continue; }
             var structs = imp[libs[i]];
 
+            var slength = structs.length;
             struct_loop:
-            for (var j = 0; j < structs.length; ++j) {
+            for (var j = 0; j < slength; ++j) {
                 var struct = structs[j];
 
                 var list = struct.synthetic ? synthetic_implementors : implementors;
 
                 if (struct.synthetic) {
-                    for (var k = 0; k < struct.types.length; k++) {
+                    var stlength = struct.types.length;
+                    for (var k = 0; k < stlength; k++) {
                         if (window.inlined_types.has(struct.types[k])) {
                             continue struct_loop;
                         }
@@ -1786,21 +1830,22 @@
                     }
                 }
 
-                var code = document.createElement('code');
+                var code = document.createElement("code");
                 code.innerHTML = struct.text;
 
-                var x = code.getElementsByTagName('a');
-                for (var k = 0; k < x.length; k++) {
-                    var href = x[k].getAttribute('href');
-                    if (href && href.indexOf('http') !== 0) {
-                        x[k].setAttribute('href', rootPath + href);
+                var x = code.getElementsByTagName("a");
+                var xlength = x.length;
+                for (var it = 0; it < xlength; it++) {
+                    var href = x[it].getAttribute("href");
+                    if (href && href.indexOf("http") !== 0) {
+                        x[it].setAttribute("href", rootPath + href);
                     }
                 }
-                var display = document.createElement('h3');
+                var display = document.createElement("h3");
                 addClass(display, "impl");
-                display.innerHTML = '<span class="in-band"><table class="table-display"><tbody>\
-                    <tr><td><code>' + code.outerHTML + '</code></td><td></td></tr></tbody></table>\
-                    </span>';
+                display.innerHTML = "<span class=\"in-band\"><table class=\"table-display\">" +
+                    "<tbody><tr><td><code>" + code.outerHTML + "</code></td><td></td></tr>" +
+                    "</tbody></table></span>";
                 list.appendChild(display);
             }
         }
@@ -1816,47 +1861,49 @@
         }
         // button will collapse the section
         // note that this text is also set in the HTML template in render.rs
-        return "\u2212"; // "\u2212" is '−' minus sign
+        return "\u2212"; // "\u2212" is "−" minus sign
     }
 
     function onEveryMatchingChild(elem, className, func) {
         if (elem && className && func) {
-            for (var i = 0; i < elem.childNodes.length; i++) {
-                if (hasClass(elem.childNodes[i], className)) {
-                    func(elem.childNodes[i]);
+            var length = elem.childNodes.length;
+            var nodes = elem.childNodes;
+            for (var i = 0; i < length; ++i) {
+                if (hasClass(nodes[i], className)) {
+                    func(nodes[i]);
                 } else {
-                    onEveryMatchingChild(elem.childNodes[i], className, func);
+                    onEveryMatchingChild(nodes[i], className, func);
                 }
             }
         }
     }
 
     function toggleAllDocs(pageId, fromAutoCollapse) {
-        var toggle = document.getElementById("toggle-all-docs");
-        if (!toggle) {
+        var innerToggle = document.getElementById("toggle-all-docs");
+        if (!innerToggle) {
             return;
         }
-        if (hasClass(toggle, "will-expand")) {
+        if (hasClass(innerToggle, "will-expand")) {
             updateLocalStorage("rustdoc-collapse", "false");
-            removeClass(toggle, "will-expand");
-            onEveryMatchingChild(toggle, "inner", function(e) {
+            removeClass(innerToggle, "will-expand");
+            onEveryMatchingChild(innerToggle, "inner", function(e) {
                 e.innerHTML = labelForToggleButton(false);
             });
-            toggle.title = "collapse all docs";
+            innerToggle.title = "collapse all docs";
             if (fromAutoCollapse !== true) {
-                onEach(document.getElementsByClassName("collapse-toggle"), function(e) {
+                onEachLazy(document.getElementsByClassName("collapse-toggle"), function(e) {
                     collapseDocs(e, "show");
                 });
             }
         } else {
             updateLocalStorage("rustdoc-collapse", "true");
-            addClass(toggle, "will-expand");
-            onEveryMatchingChild(toggle, "inner", function(e) {
+            addClass(innerToggle, "will-expand");
+            onEveryMatchingChild(innerToggle, "inner", function(e) {
                 e.innerHTML = labelForToggleButton(true);
             });
-            toggle.title = "expand all docs";
+            innerToggle.title = "expand all docs";
             if (fromAutoCollapse !== true) {
-                onEach(document.getElementsByClassName("collapse-toggle"), function(e) {
+                onEachLazy(document.getElementsByClassName("collapse-toggle"), function(e) {
                     collapseDocs(e, "hide", pageId);
                 });
             }
@@ -1870,27 +1917,58 @@
 
         function adjustToggle(arg) {
             return function(e) {
-                if (hasClass(e, 'toggle-label')) {
+                if (hasClass(e, "toggle-label")) {
                     if (arg) {
-                        e.style.display = 'inline-block';
+                        e.style.display = "inline-block";
                     } else {
-                        e.style.display = 'none';
+                        e.style.display = "none";
                     }
                 }
-                if (hasClass(e, 'inner')) {
+                if (hasClass(e, "inner")) {
                     e.innerHTML = labelForToggleButton(arg);
                 }
             };
-        };
+        }
 
-        if (!hasClass(toggle.parentNode, "impl")) {
-            var relatedDoc = toggle.parentNode.nextElementSibling;
+        function implHider(addOrRemove) {
+            return function(n) {
+                var is_method = hasClass(n, "method");
+                if (is_method || hasClass(n, "type")) {
+                    if (is_method === true) {
+                        if (addOrRemove) {
+                            addClass(n, "hidden-by-impl-hider");
+                        } else {
+                            removeClass(n, "hidden-by-impl-hider");
+                        }
+                    }
+                    var ns = n.nextElementSibling;
+                    while (true) {
+                        if (ns && (
+                                hasClass(ns, "docblock") ||
+                                hasClass(ns, "stability"))) {
+                            if (addOrRemove) {
+                                addClass(ns, "hidden-by-impl-hider");
+                            } else {
+                                removeClass(ns, "hidden-by-impl-hider");
+                            }
+                            ns = ns.nextElementSibling;
+                            continue;
+                        }
+                        break;
+                    }
+                }
+            };
+        }
+
+        var relatedDoc;
+        var action = mode;
+        if (hasClass(toggle.parentNode, "impl") === false) {
+            relatedDoc = toggle.parentNode.nextElementSibling;
             if (hasClass(relatedDoc, "stability")) {
                 relatedDoc = relatedDoc.nextElementSibling;
             }
             if (hasClass(relatedDoc, "docblock") || hasClass(relatedDoc, "sub-variant")) {
-                var action = mode;
-                if (action === "toggle") {
+                if (mode === "toggle") {
                     if (hasClass(relatedDoc, "hidden-by-usual-hider")) {
                         action = "show";
                     } else {
@@ -1899,67 +1977,35 @@
                 }
                 if (action === "hide") {
                     addClass(relatedDoc, "hidden-by-usual-hider");
-                    onEach(toggle.childNodes, adjustToggle(true));
-                    addClass(toggle.parentNode, 'collapsed');
+                    onEachLazy(toggle.childNodes, adjustToggle(true));
+                    addClass(toggle.parentNode, "collapsed");
                 } else if (action === "show") {
                     removeClass(relatedDoc, "hidden-by-usual-hider");
-                    removeClass(toggle.parentNode, 'collapsed');
-                    onEach(toggle.childNodes, adjustToggle(false));
+                    removeClass(toggle.parentNode, "collapsed");
+                    onEachLazy(toggle.childNodes, adjustToggle(false));
                 }
             }
         } else {
             // we are collapsing the impl block
-            function implHider(addOrRemove) {
-                return function(n) {
-                    var is_method = hasClass(n, "method");
-                    if (is_method || hasClass(n, "type")) {
-                        if (is_method === true) {
-                            if (addOrRemove) {
-                                addClass(n, "hidden-by-impl-hider");
-                            } else {
-                                removeClass(n, "hidden-by-impl-hider");
-                            }
-                        }
-                        var ns = n.nextElementSibling;
-                        while (true) {
-                            if (ns && (
-                                    hasClass(ns, "docblock") ||
-                                    hasClass(ns, "stability"))) {
-                                if (addOrRemove) {
-                                    addClass(ns, "hidden-by-impl-hider");
-                                } else {
-                                    removeClass(ns, "hidden-by-impl-hider");
-                                }
-                                ns = ns.nextElementSibling;
-                                continue;
-                            }
-                            break;
-                        }
-                    }
-                }
-            }
 
             var parentElem = toggle.parentNode;
-            var relatedDoc = parentElem;
+            relatedDoc = parentElem;
             var docblock = relatedDoc.nextElementSibling;
 
-            while (!hasClass(relatedDoc, "impl-items")) {
+            while (hasClass(relatedDoc, "impl-items") === false) {
                 relatedDoc = relatedDoc.nextElementSibling;
             }
 
-            if ((!relatedDoc && !hasClass(docblock, "docblock")) ||
-                (pageId && onEach(relatedDoc.childNodes, function(e) {
-                    return e.id === pageId;
-                }) === true)) {
+            if ((!relatedDoc && hasClass(docblock, "docblock") === false) ||
+                (pageId && document.getElementById(pageId))) {
                 return;
             }
 
             // Hide all functions, but not associated types/consts
 
-            var action = mode;
-            if (action === "toggle") {
+            if (mode === "toggle") {
                 if (hasClass(relatedDoc, "fns-now-collapsed") ||
-                    hasClass(docblock,  "hidden-by-impl-hider")) {
+                    hasClass(docblock, "hidden-by-impl-hider")) {
                     action = "show";
                 } else {
                     action = "hide";
@@ -1969,13 +2015,25 @@
             if (action === "show") {
                 removeClass(relatedDoc, "fns-now-collapsed");
                 removeClass(docblock, "hidden-by-usual-hider");
-                onEach(toggle.childNodes, adjustToggle(false));
-                onEach(relatedDoc.childNodes, implHider(false));
+                onEachLazy(toggle.childNodes, adjustToggle(false));
+                onEachLazy(relatedDoc.childNodes, implHider(false));
             } else if (action === "hide") {
                 addClass(relatedDoc, "fns-now-collapsed");
                 addClass(docblock, "hidden-by-usual-hider");
-                onEach(toggle.childNodes, adjustToggle(true));
-                onEach(relatedDoc.childNodes, implHider(true));
+                onEachLazy(toggle.childNodes, adjustToggle(true));
+                onEachLazy(relatedDoc.childNodes, implHider(true));
+            }
+        }
+    }
+
+    function collapser(e, collapse) {
+        // inherent impl ids are like "impl" or impl-<number>'.
+        // they will never be hidden by default.
+        var n = e.parentElement;
+        if (n.id.match(/^impl(?:-\d+)?$/) === null) {
+            // Automatically minimize all non-inherent impls
+            if (collapse || hasClass(n, "impl")) {
+                collapseDocs(e, "hide", pageId);
             }
         }
     }
@@ -1983,88 +2041,112 @@
     function autoCollapse(pageId, collapse) {
         if (collapse) {
             toggleAllDocs(pageId, true);
-        }
-        var collapser = function(e) {
-                // inherent impl ids are like 'impl' or impl-<number>'.
-                // they will never be hidden by default.
-                var n = e.parentElement;
-                if (n.id.match(/^impl(?:-\d+)?$/) === null) {
-                    // Automatically minimize all non-inherent impls
-                    if (collapse || hasClass(n, 'impl')) {
-                        collapseDocs(e, "hide", pageId);
-                    }
-                }
-        };
-        if (getCurrentValue('rustdoc-trait-implementations') !== "false") {
-            var impl_list = document.getElementById('implementations-list');
+        } else if (getCurrentValue("rustdoc-trait-implementations") !== "false") {
+            var impl_list = document.getElementById("implementations-list");
 
             if (impl_list !== null) {
-                onEach(impl_list.getElementsByClassName("collapse-toggle"), collapser);
-            }
-        }
-        if (getCurrentValue('rustdoc-method-docs') !== "false") {
-            var implItems = document.getElementsByClassName('impl-items');
-
-            if (implItems && implItems.length > 0) {
-                onEach(implItems, function(elem) {
-                    onEach(elem.getElementsByClassName("collapse-toggle"), collapser);
+                onEachLazy(impl_list.getElementsByClassName("collapse-toggle"), function(e) {
+                    collapser(e, collapse);
                 });
             }
         }
     }
 
-    var x = document.getElementById('toggle-all-docs');
-    if (x) {
-        x.onclick = toggleAllDocs;
+    var toggles = document.getElementById("toggle-all-docs");
+    if (toggles) {
+        toggles.onclick = toggleAllDocs;
     }
 
     function insertAfter(newNode, referenceNode) {
         referenceNode.parentNode.insertBefore(newNode, referenceNode.nextSibling);
     }
 
-    function checkIfThereAreMethods(elems) {
-        var areThereMethods = false;
-
-        onEach(elems, function(e) {
-            if (hasClass(e, "method")) {
-                areThereMethods = true;
-                return true;
-            }
-        });
-        return areThereMethods;
+    function createSimpleToggle(sectionIsCollapsed) {
+        var toggle = document.createElement("a");
+        toggle.href = "javascript:void(0)";
+        toggle.className = "collapse-toggle";
+        toggle.innerHTML = "[<span class=\"inner\">" + labelForToggleButton(sectionIsCollapsed) +
+                           "</span>]";
+        return toggle;
     }
 
-    var toggle = document.createElement('a');
-    toggle.href = 'javascript:void(0)';
-    toggle.className = 'collapse-toggle';
-    toggle.innerHTML = "[<span class='inner'>" + labelForToggleButton(false) + "</span>]";
+    var toggle = createSimpleToggle(false);
 
     var func = function(e) {
         var next = e.nextElementSibling;
-        if (hasClass(e, 'impl') && next && hasClass(next, 'docblock')) {
+        if (!next) {
+            return;
+        }
+        if (hasClass(next, "docblock") ||
+            (hasClass(next, "stability") &&
+             hasClass(next.nextElementSibling, "docblock"))) {
+            insertAfter(toggle.cloneNode(true), e.childNodes[e.childNodes.length - 1]);
+        }
+    };
+
+    var funcImpl = function(e) {
+        var next = e.nextElementSibling;
+        if (next && hasClass(next, "docblock")) {
             next = next.nextElementSibling;
         }
         if (!next) {
             return;
         }
-        if ((hasClass(e, 'method') || hasClass(e, 'associatedconstant') ||
-             checkIfThereAreMethods(next.childNodes)) &&
-            (hasClass(next, 'docblock') ||
-             hasClass(e, 'impl') ||
-             (hasClass(next, 'stability') &&
-              hasClass(next.nextElementSibling, 'docblock')))) {
+        if (next.getElementsByClassName("method").length > 0 && hasClass(e, "impl")) {
             insertAfter(toggle.cloneNode(true), e.childNodes[e.childNodes.length - 1]);
         }
     };
-    onEach(document.getElementsByClassName('method'), func);
-    onEach(document.getElementsByClassName('associatedconstant'), func);
-    onEach(document.getElementsByClassName('impl'), func);
-    onEach(document.getElementsByClassName('impl-items'), function(e) {
-        onEach(e.getElementsByClassName('associatedconstant'), func);
-        var hiddenElems = e.getElementsByClassName('hidden');
+
+    onEachLazy(document.getElementsByClassName("method"), func);
+    onEachLazy(document.getElementsByClassName("associatedconstant"), func);
+    onEachLazy(document.getElementsByClassName("impl"), funcImpl);
+    var impl_call = function() {};
+    if (getCurrentValue("rustdoc-method-docs") !== "false") {
+        impl_call = function(e, newToggle, pageId) {
+            if (e.id.match(/^impl(?:-\d+)?$/) === null) {
+                // Automatically minimize all non-inherent impls
+                if (hasClass(e, "impl")) {
+                    collapseDocs(newToggle, "hide", pageId);
+                }
+            }
+        };
+    }
+    var pageId = getPageId();
+    var newToggle = document.createElement("a");
+    newToggle.href = "javascript:void(0)";
+    newToggle.className = "collapse-toggle hidden-default collapsed";
+    newToggle.innerHTML = "[<span class=\"inner\">" + labelForToggleButton(true) +
+                          "</span>] Show hidden undocumented items";
+    function toggleClicked() {
+        if (hasClass(this, "collapsed")) {
+            removeClass(this, "collapsed");
+            onEachLazy(this.parentNode.getElementsByClassName("hidden"), function(x) {
+                if (hasClass(x, "content") === false) {
+                    removeClass(x, "hidden");
+                    addClass(x, "x");
+                }
+            }, true);
+            this.innerHTML = "[<span class=\"inner\">" + labelForToggleButton(false) +
+                             "</span>] Hide undocumented items";
+        } else {
+            addClass(this, "collapsed");
+            onEachLazy(this.parentNode.getElementsByClassName("x"), function(x) {
+                if (hasClass(x, "content") === false) {
+                    addClass(x, "hidden");
+                    removeClass(x, "x");
+                }
+            }, true);
+            this.innerHTML = "[<span class=\"inner\">" + labelForToggleButton(true) +
+                             "</span>] Show hidden undocumented items";
+        }
+    }
+    onEachLazy(document.getElementsByClassName("impl-items"), function(e) {
+        onEachLazy(e.getElementsByClassName("associatedconstant"), func);
+        var hiddenElems = e.getElementsByClassName("hidden");
         var needToggle = false;
 
-        for (var i = 0; i < hiddenElems.length; ++i) {
+        var hlength = hiddenElems.length;
+        for (var i = 0; i < hlength; ++i) {
             if (hasClass(hiddenElems[i], "content") === false &&
                 hasClass(hiddenElems[i], "docblock") === false) {
                 needToggle = true;
@@ -2072,46 +2154,21 @@
             }
         }
         if (needToggle === true) {
-            var newToggle = document.createElement('a');
-            newToggle.href = 'javascript:void(0)';
-            newToggle.className = 'collapse-toggle hidden-default collapsed';
-            newToggle.innerHTML = "[<span class='inner'>" + labelForToggleButton(true) + "</span>" +
-                                  "] Show hidden undocumented items";
-            newToggle.onclick = function() {
-                if (hasClass(this, "collapsed")) {
-                    removeClass(this, "collapsed");
-                    onEach(this.parentNode.getElementsByClassName("hidden"), function(x) {
-                        if (hasClass(x, "content") === false) {
-                            removeClass(x, "hidden");
-                            addClass(x, "x");
-                        }
-                    }, true);
-                    this.innerHTML = "[<span class='inner'>" + labelForToggleButton(false) +
-                                     "</span>] Hide undocumented items"
-                } else {
-                    addClass(this, "collapsed");
-                    onEach(this.parentNode.getElementsByClassName("x"), function(x) {
-                        if (hasClass(x, "content") === false) {
-                            addClass(x, "hidden");
-                            removeClass(x, "x");
-                        }
-                    }, true);
-                    this.innerHTML = "[<span class='inner'>" + labelForToggleButton(true) +
-                                     "</span>] Show hidden undocumented items";
-                }
-            };
-            e.insertBefore(newToggle, e.firstChild);
+            var inner_toggle = newToggle.cloneNode(true);
+            inner_toggle.onclick = toggleClicked;
+            e.insertBefore(inner_toggle, e.firstChild);
+            impl_call(e, inner_toggle, pageId);
         }
     });
 
     function createToggle(otherMessage, fontSize, extraClass, show) {
-        var span = document.createElement('span');
-        span.className = 'toggle-label';
+        var span = document.createElement("span");
+        span.className = "toggle-label";
         if (show) {
-            span.style.display = 'none';
+            span.style.display = "none";
         }
         if (!otherMessage) {
-            span.innerHTML = '&nbsp;Expand&nbsp;description';
+            span.innerHTML = "&nbsp;Expand&nbsp;description";
         } else {
             span.innerHTML = otherMessage;
         }
@@ -2123,13 +2180,13 @@
         var mainToggle = toggle.cloneNode(true);
         mainToggle.appendChild(span);
 
-        var wrapper = document.createElement('div');
-        wrapper.className = 'toggle-wrapper';
+        var wrapper = document.createElement("div");
+        wrapper.className = "toggle-wrapper";
         if (!show) {
-            addClass(wrapper, 'collapsed');
-            var inner = mainToggle.getElementsByClassName('inner');
+            addClass(wrapper, "collapsed");
+            var inner = mainToggle.getElementsByClassName("inner");
             if (inner && inner.length > 0) {
-                inner[0].innerHTML = '+';
+                inner[0].innerHTML = "+";
             }
         }
         if (extraClass) {
@@ -2139,21 +2196,21 @@
         return wrapper;
     }
 
-    var showItemDeclarations = getCurrentValue('rustdoc-item-declarations') === "false";
+    var showItemDeclarations = getCurrentValue("rustdoc-item-declarations") === "false";
     function buildToggleWrapper(e) {
-        if (hasClass(e, 'autohide')) {
+        if (hasClass(e, "autohide")) {
             var wrap = e.previousElementSibling;
-            if (wrap && hasClass(wrap, 'toggle-wrapper')) {
-                var toggle = wrap.childNodes[0];
-                var extra = e.childNodes[0].tagName === 'H3';
+            if (wrap && hasClass(wrap, "toggle-wrapper")) {
+                var inner_toggle = wrap.childNodes[0];
+                var extra = e.childNodes[0].tagName === "H3";
 
-                e.style.display = 'none';
-                addClass(wrap, 'collapsed');
-                onEach(toggle.getElementsByClassName('inner'), function(e) {
+                e.style.display = "none";
+                addClass(wrap, "collapsed");
+                onEachLazy(inner_toggle.getElementsByClassName("inner"), function(e) {
                     e.innerHTML = labelForToggleButton(true);
                 });
-                onEach(toggle.getElementsByClassName('toggle-label'), function(e) {
-                    e.style.display = 'inline-block';
+                onEachLazy(inner_toggle.getElementsByClassName("toggle-label"), function(e) {
+                    e.style.display = "inline-block";
                     if (extra === true) {
                         i_e.innerHTML = " Show " + e.childNodes[0].innerHTML;
                     }
@@ -2161,28 +2218,28 @@
             }
         }
         if (e.parentNode.id === "main") {
-            var otherMessage = '';
+            var otherMessage = "";
             var fontSize;
             var extraClass;
 
             if (hasClass(e, "type-decl")) {
                 fontSize = "20px";
-                otherMessage = '&nbsp;Show&nbsp;declaration';
+                otherMessage = "&nbsp;Show&nbsp;declaration";
                 if (showItemDeclarations === false) {
-                    extraClass = 'collapsed';
+                    extraClass = "collapsed";
                 }
             } else if (hasClass(e, "sub-variant")) {
-                otherMessage = '&nbsp;Show&nbsp;fields';
+                otherMessage = "&nbsp;Show&nbsp;fields";
             } else if (hasClass(e, "non-exhaustive")) {
-                otherMessage = '&nbsp;This&nbsp;';
+                otherMessage = "&nbsp;This&nbsp;";
                 if (hasClass(e, "non-exhaustive-struct")) {
-                    otherMessage += 'struct';
+                    otherMessage += "struct";
                 } else if (hasClass(e, "non-exhaustive-enum")) {
-                    otherMessage += 'enum';
+                    otherMessage += "enum";
                 } else if (hasClass(e, "non-exhaustive-type")) {
-                    otherMessage += 'type';
+                    otherMessage += "type";
                 }
-                otherMessage += '&nbsp;is&nbsp;marked&nbsp;as&nbsp;non-exhaustive';
+                otherMessage += "&nbsp;is&nbsp;marked&nbsp;as&nbsp;non-exhaustive";
             } else if (hasClass(e.childNodes[0], "impl-items")) {
                 extraClass = "marg-left";
             }
@@ -2199,21 +2256,8 @@
         }
     }
 
-    onEach(document.getElementsByClassName('docblock'), buildToggleWrapper);
-    onEach(document.getElementsByClassName('sub-variant'), buildToggleWrapper);
-
-    function createToggleWrapper(tog) {
-        var span = document.createElement('span');
-        span.className = 'toggle-label';
-        span.style.display = 'none';
-        span.innerHTML = '&nbsp;Expand&nbsp;attributes';
-        tog.appendChild(span);
-
-        var wrapper = document.createElement('div');
-        wrapper.className = 'toggle-wrapper toggle-attributes';
-        wrapper.appendChild(tog);
-        return wrapper;
-    }
+    onEachLazy(document.getElementsByClassName("docblock"), buildToggleWrapper);
+    onEachLazy(document.getElementsByClassName("sub-variant"), buildToggleWrapper);
 
     // In the search display, allows to switch between tabs.
     function printTab(nb) {
@@ -2221,24 +2265,37 @@
             currentTab = nb;
         }
         var nb_copy = nb;
-        onEach(document.getElementById('titles').childNodes, function(elem) {
+        onEachLazy(document.getElementById("titles").childNodes, function(elem) {
             if (nb_copy === 0) {
-                addClass(elem, 'selected');
+                addClass(elem, "selected");
             } else {
-                removeClass(elem, 'selected');
+                removeClass(elem, "selected");
             }
             nb_copy -= 1;
         });
-        onEach(document.getElementById('results').childNodes, function(elem) {
+        onEachLazy(document.getElementById("results").childNodes, function(elem) {
             if (nb === 0) {
-                elem.style.display = '';
+                elem.style.display = "";
             } else {
-                elem.style.display = 'none';
+                elem.style.display = "none";
             }
             nb -= 1;
         });
     }
 
+    function createToggleWrapper(tog) {
+        var span = document.createElement("span");
+        span.className = "toggle-label";
+        span.style.display = "none";
+        span.innerHTML = "&nbsp;Expand&nbsp;attributes";
+        tog.appendChild(span);
+
+        var wrapper = document.createElement("div");
+        wrapper.className = "toggle-wrapper toggle-attributes";
+        wrapper.appendChild(tog);
+        return wrapper;
+    }
+
     // To avoid checking on "rustdoc-item-attributes" value on every loop...
     var itemAttributesFunc = function() {};
     if (getCurrentValue("rustdoc-item-attributes") !== "false") {
@@ -2246,8 +2303,9 @@
             collapseDocs(x.previousSibling.childNodes[0], "toggle");
         };
     }
-    onEach(document.getElementById('main').getElementsByClassName('attributes'), function(i_e) {
-        i_e.parentNode.insertBefore(createToggleWrapper(toggle.cloneNode(true)), i_e);
+    var attributesToggle = createToggleWrapper(createSimpleToggle(false));
+    onEachLazy(main.getElementsByClassName("attributes"), function(i_e) {
+        i_e.parentNode.insertBefore(attributesToggle.cloneNode(true), i_e);
         itemAttributesFunc(i_e);
     });
 
@@ -2255,45 +2313,45 @@
     var lineNumbersFunc = function() {};
     if (getCurrentValue("rustdoc-line-numbers") === "true") {
         lineNumbersFunc = function(x) {
-            var count = x.textContent.split('\n').length;
+            var count = x.textContent.split("\n").length;
             var elems = [];
             for (var i = 0; i < count; ++i) {
                 elems.push(i + 1);
             }
-            var node = document.createElement('pre');
-            addClass(node, 'line-number');
-            node.innerHTML = elems.join('\n');
+            var node = document.createElement("pre");
+            addClass(node, "line-number");
+            node.innerHTML = elems.join("\n");
             x.parentNode.insertBefore(node, x);
         };
     }
-    onEach(document.getElementsByClassName('rust-example-rendered'), function(e) {
-        if (hasClass(e, 'compile_fail')) {
+    onEachLazy(document.getElementsByClassName("rust-example-rendered"), function(e) {
+        if (hasClass(e, "compile_fail")) {
             e.addEventListener("mouseover", function(event) {
-                this.parentElement.previousElementSibling.childNodes[0].style.color = '#f00';
+                this.parentElement.previousElementSibling.childNodes[0].style.color = "#f00";
             });
             e.addEventListener("mouseout", function(event) {
-                this.parentElement.previousElementSibling.childNodes[0].style.color = '';
+                this.parentElement.previousElementSibling.childNodes[0].style.color = "";
             });
-        } else if (hasClass(e, 'ignore')) {
+        } else if (hasClass(e, "ignore")) {
             e.addEventListener("mouseover", function(event) {
-                this.parentElement.previousElementSibling.childNodes[0].style.color = '#ff9200';
+                this.parentElement.previousElementSibling.childNodes[0].style.color = "#ff9200";
             });
             e.addEventListener("mouseout", function(event) {
-                this.parentElement.previousElementSibling.childNodes[0].style.color = '';
+                this.parentElement.previousElementSibling.childNodes[0].style.color = "";
             });
         }
         lineNumbersFunc(e);
     });
 
     function showModal(content) {
-        var modal = document.createElement('div');
+        var modal = document.createElement("div");
         modal.id = "important";
-        addClass(modal, 'modal');
-        modal.innerHTML = '<div class="modal-content"><div class="close" id="modal-close">✕</div>' +
-                          '<div class="whiter"></div><span class="docblock">' + content +
-                          '</span></div>';
-        document.getElementsByTagName('body')[0].appendChild(modal);
-        document.getElementById('modal-close').onclick = hideModal;
+        addClass(modal, "modal");
+        modal.innerHTML = "<div class=\"modal-content\"><div class=\"close\" id=\"modal-close\">✕" +
+                          "</div><div class=\"whiter\"></div><span class=\"docblock\">" + content +
+                          "</span></div>";
+        document.getElementsByTagName("body")[0].appendChild(modal);
+        document.getElementById("modal-close").onclick = hideModal;
         modal.onclick = hideModal;
     }
 
@@ -2304,7 +2362,7 @@
         }
     }
 
-    onEach(document.getElementsByClassName('important-traits'), function(e) {
+    onEachLazy(document.getElementsByClassName("important-traits"), function(e) {
         e.onclick = function() {
             showModal(e.lastElementChild.innerHTML);
         };
@@ -2312,7 +2370,7 @@
 
     function putBackSearch(search_input) {
         if (search_input.value !== "") {
-            addClass(document.getElementById("main"), "hidden");
+            addClass(main, "hidden");
             removeClass(document.getElementById("search"), "hidden");
             if (browserSupportsHistoryApi()) {
                 history.replaceState(search_input.value,
@@ -2330,16 +2388,16 @@
 
     var params = getQueryStringParams();
     if (params && params.search) {
-        addClass(document.getElementById("main"), "hidden");
+        addClass(main, "hidden");
         var search = document.getElementById("search");
         removeClass(search, "hidden");
-        search.innerHTML = '<h3 style="text-align: center;">Loading search results...</h3>';
+        search.innerHTML = "<h3 style=\"text-align: center;\">Loading search results...</h3>";
     }
 
     var sidebar_menu = document.getElementsByClassName("sidebar-menu")[0];
     if (sidebar_menu) {
         sidebar_menu.onclick = function() {
-            var sidebar = document.getElementsByClassName('sidebar')[0];
+            var sidebar = document.getElementsByClassName("sidebar")[0];
             if (hasClass(sidebar, "mobile") === true) {
                 hideSidebar();
             } else {
@@ -2355,7 +2413,18 @@
     autoCollapse(getPageId(), getCurrentValue("rustdoc-collapse") === "true");
 
     if (window.location.hash && window.location.hash.length > 0) {
-        expandSection(window.location.hash.replace(/^#/, ''));
+        expandSection(window.location.hash.replace(/^#/, ""));
+    }
+
+    if (main) {
+        onEachLazy(main.getElementsByClassName("loading-content"), function(e) {
+            e.remove();
+        });
+        onEachLazy(main.childNodes, function(e) {
+            if (e.tagName === "H2" || e.tagName === "H3") {
+                e.nextElementSibling.style.display = "block";
+            }
+        });
     }
 
     function addSearchOptions(crates) {
@@ -2394,10 +2463,10 @@
 
 // Sets the focus on the search bar at the top of the page
 function focusSearchBar() {
-    document.getElementsByClassName('search-input')[0].focus();
+    document.getElementsByClassName("search-input")[0].focus();
 }
 
 // Removes the focus from the search bar
 function defocusSearchBar() {
-    document.getElementsByClassName('search-input')[0].blur();
+    document.getElementsByClassName("search-input")[0].blur();
 }
diff --git a/src/librustdoc/html/static/noscript.css b/src/librustdoc/html/static/noscript.css
new file mode 100644
index 0000000..f4de75f
--- /dev/null
+++ b/src/librustdoc/html/static/noscript.css
@@ -0,0 +1,19 @@
+/**
+ * Copyright 2018 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.
+ */
+
+#main > h2 + div, #main > h2 + h3, #main > h3 + div {
+	display: block;
+}
+
+.loading-content {
+	display: none;
+}
diff --git a/src/librustdoc/html/static/rustdoc.css b/src/librustdoc/html/static/rustdoc.css
index cd5a8a7..d1336b1 100644
--- a/src/librustdoc/html/static/rustdoc.css
+++ b/src/librustdoc/html/static/rustdoc.css
@@ -368,6 +368,10 @@
 #main > .docblock h2 { font-size: 1.15em; }
 #main > .docblock h3, #main > .docblock h4, #main > .docblock h5 { font-size: 1em; }
 
+#main > h2 + div, #main > h2 + h3, #main > h3 + div {
+	display: none;
+}
+
 .docblock h1 { font-size: 1em; }
 .docblock h2 { font-size: 0.95em; }
 .docblock h3, .docblock h4, .docblock h5 { font-size: 0.9em; }
diff --git a/src/librustdoc/html/static/storage.js b/src/librustdoc/html/static/storage.js
index e8f0c03..d1c377b 100644
--- a/src/librustdoc/html/static/storage.js
+++ b/src/librustdoc/html/static/storage.js
@@ -19,55 +19,38 @@
 var savedHref = [];
 
 function hasClass(elem, className) {
-    if (elem && className && elem.className) {
-        var elemClass = elem.className;
-        var start = elemClass.indexOf(className);
-        if (start === -1) {
-            return false;
-        } else if (elemClass.length === className.length) {
-            return true;
-        } else {
-            if (start > 0 && elemClass[start - 1] !== ' ') {
-                return false;
-            }
-            var end = start + className.length;
-            return !(end < elemClass.length && elemClass[end] !== ' ');
-        }
-    }
-    return false;
+    return elem && elem.classList && elem.classList.contains(className);
 }
 
 function addClass(elem, className) {
-    if (elem && className && !hasClass(elem, className)) {
-        if (elem.className && elem.className.length > 0) {
-            elem.className += ' ' + className;
-        } else {
-            elem.className = className;
-        }
+    if (!elem || !elem.classList) {
+        return;
     }
+    elem.classList.add(className);
 }
 
 function removeClass(elem, className) {
-    if (elem && className && elem.className) {
-        elem.className = (" " + elem.className + " ").replace(" " + className + " ", " ")
-                                                     .trim();
+    if (!elem || !elem.classList) {
+        return;
     }
+    elem.classList.remove(className);
 }
 
 function isHidden(elem) {
-    return (elem.offsetParent === null)
+    return elem.offsetParent === null;
 }
 
 function onEach(arr, func, reversed) {
     if (arr && arr.length > 0 && func) {
+        var length = arr.length;
         if (reversed !== true) {
-            for (var i = 0; i < arr.length; ++i) {
+            for (var i = 0; i < length; ++i) {
                 if (func(arr[i]) === true) {
                     return true;
                 }
             }
         } else {
-            for (var i = arr.length - 1; i >= 0; --i) {
+            for (var i = length - 1; i >= 0; --i) {
                 if (func(arr[i]) === true) {
                     return true;
                 }
@@ -77,6 +60,13 @@
     return false;
 }
 
+function onEachLazy(lazyArray, func, reversed) {
+    return onEach(
+        Array.prototype.slice.call(lazyArray),
+        func,
+        reversed);
+}
+
 function usableLocalStorage() {
     // Check if the browser supports localStorage at all:
     if (typeof(Storage) === "undefined") {
@@ -133,8 +123,8 @@
     });
     if (found === true) {
         styleElem.href = newHref;
-        updateLocalStorage('rustdoc-theme', newTheme);
+        updateLocalStorage("rustdoc-theme", newTheme);
     }
 }
 
-switchTheme(currentTheme, mainTheme, getCurrentValue('rustdoc-theme') || 'light');
+switchTheme(currentTheme, mainTheme, getCurrentValue("rustdoc-theme") || "light");
diff --git a/src/librustdoc/html/static_files.rs b/src/librustdoc/html/static_files.rs
index a485fac..f71b2a8 100644
--- a/src/librustdoc/html/static_files.rs
+++ b/src/librustdoc/html/static_files.rs
@@ -23,6 +23,9 @@
 /// The file contents of `settings.css`, responsible for the items on the settings page.
 pub static SETTINGS_CSS: &'static str = include_str!("static/settings.css");
 
+/// The file contents of the `noscript.css` file, used in case JS isn't supported or is disabled.
+pub static NOSCRIPT_CSS: &'static str = include_str!("static/noscript.css");
+
 /// The file contents of `normalize.css`, included to even out standard elements between browser
 /// implementations.
 pub static NORMALIZE_CSS: &'static str = include_str!("static/normalize.css");
diff --git a/src/librustdoc/markdown.rs b/src/librustdoc/markdown.rs
index e0e0be7..504567e 100644
--- a/src/librustdoc/markdown.rs
+++ b/src/librustdoc/markdown.rs
@@ -35,7 +35,7 @@
     for line in s.lines() {
         if line.starts_with("# ") || line.starts_with("%") {
             // trim the whitespace after the symbol
-            metadata.push(line[1..].trim_left());
+            metadata.push(line[1..].trim_start());
             count += line.len() + 1;
         } else {
             return (metadata, &s[count..]);
diff --git a/src/librustdoc/passes/collect_intra_doc_links.rs b/src/librustdoc/passes/collect_intra_doc_links.rs
index 426d3f3..2e8bfd8 100644
--- a/src/librustdoc/passes/collect_intra_doc_links.rs
+++ b/src/librustdoc/passes/collect_intra_doc_links.rs
@@ -294,23 +294,23 @@
                      "trait@", "union@"].iter()
                                       .find(|p| link.starts_with(**p)) {
                     kind = PathKind::Type;
-                    link.trim_left_matches(prefix)
+                    link.trim_start_matches(prefix)
                 } else if let Some(prefix) =
                     ["const@", "static@",
                      "value@", "function@", "mod@",
                      "fn@", "module@", "method@"]
                         .iter().find(|p| link.starts_with(**p)) {
                     kind = PathKind::Value;
-                    link.trim_left_matches(prefix)
+                    link.trim_start_matches(prefix)
                 } else if link.ends_with("()") {
                     kind = PathKind::Value;
-                    link.trim_right_matches("()")
+                    link.trim_end_matches("()")
                 } else if link.starts_with("macro@") {
                     kind = PathKind::Macro;
-                    link.trim_left_matches("macro@")
+                    link.trim_start_matches("macro@")
                 } else if link.ends_with('!') {
                     kind = PathKind::Macro;
-                    link.trim_right_matches('!')
+                    link.trim_end_matches('!')
                 } else {
                     &link[..]
                 }.trim();
@@ -459,6 +459,19 @@
     start.to(end)
 }
 
+/// Reports a resolution failure diagnostic.
+///
+/// Ideally we can report the diagnostic with the actual span in the source where the link failure
+/// occurred. However, there's a mismatch between the span in the source code and the span in the
+/// markdown, so we have to do a bit of work to figure out the correspondence.
+///
+/// It's not too hard to find the span for sugared doc comments (`///` and `/**`), because the
+/// source will match the markdown exactly, excluding the comment markers. However, it's much more
+/// difficult to calculate the spans for unsugared docs, because we have to deal with escaping and
+/// other source features. So, we attempt to find the exact source span of the resolution failure
+/// in sugared docs, but use the span of the documentation attributes themselves for unsugared
+/// docs. Because this span might be overly large, we display the markdown line containing the
+/// failure as a note.
 fn resolution_failure(
     cx: &DocContext,
     attrs: &Attributes,
@@ -469,47 +482,75 @@
     let sp = span_of_attrs(attrs);
     let msg = format!("`[{}]` cannot be resolved, ignoring it...", path_str);
 
-    let code_dox = sp.to_src(cx);
-
-    let doc_comment_padding = 3;
     let mut diag = if let Some(link_range) = link_range {
-        // blah blah blah\nblah\nblah [blah] blah blah\nblah blah
-        //                       ^    ~~~~~~
-        //                       |    link_range
-        //                       last_new_line_offset
+        let src = cx.sess().source_map().span_to_snippet(sp);
+        let is_all_sugared_doc = attrs.doc_strings.iter().all(|frag| match frag {
+            DocFragment::SugaredDoc(..) => true,
+            _ => false,
+        });
 
-        let mut diag;
-        if dox.lines().count() == code_dox.lines().count() {
-            let line_offset = dox[..link_range.start].lines().count();
-            // The span starts in the `///`, so we don't have to account for the leading whitespace.
-            let code_dox_len = if line_offset <= 1 {
-                doc_comment_padding
-            } else {
-                // The first `///`.
-                doc_comment_padding +
-                    // Each subsequent leading whitespace and `///`.
-                    code_dox.lines().skip(1).take(line_offset - 1).fold(0, |sum, line| {
-                        sum + doc_comment_padding + line.len() - line.trim_start().len()
-                    })
-            };
+        if let (Ok(src), true) = (src, is_all_sugared_doc) {
+            // The number of markdown lines up to and including the resolution failure.
+            let num_lines = dox[..link_range.start].lines().count();
 
-            // Extract the specific span.
+            // We use `split_terminator('\n')` instead of `lines()` when counting bytes to ensure
+            // that DOS-style line endings do not cause the spans to be calculated incorrectly.
+            let mut src_lines = src.split_terminator('\n');
+            let mut md_lines = dox.split_terminator('\n').take(num_lines).peekable();
+
+            // The number of bytes from the start of the source span to the resolution failure that
+            // are *not* part of the markdown, like comment markers.
+            let mut extra_src_bytes = 0;
+
+            while let Some(md_line) = md_lines.next() {
+                loop {
+                    let source_line = src_lines
+                        .next()
+                        .expect("could not find markdown line in source");
+
+                    match source_line.find(md_line) {
+                        Some(offset) => {
+                            extra_src_bytes += if md_lines.peek().is_some() {
+                                source_line.len() - md_line.len()
+                            } else {
+                                offset
+                            };
+                            break;
+                        }
+                        None => {
+                            // Since this is a source line that doesn't include a markdown line,
+                            // we have to count the newline that we split from earlier.
+                            extra_src_bytes += source_line.len() + 1;
+                        }
+                    }
+                }
+            }
+
             let sp = sp.from_inner_byte_pos(
-                link_range.start + code_dox_len,
-                link_range.end + code_dox_len,
+                link_range.start + extra_src_bytes,
+                link_range.end + extra_src_bytes,
             );
 
-            diag = cx.tcx.struct_span_lint_node(lint::builtin::INTRA_DOC_LINK_RESOLUTION_FAILURE,
-                                                NodeId::from_u32(0),
-                                                sp,
-                                                &msg);
+            let mut diag = cx.tcx.struct_span_lint_node(
+                lint::builtin::INTRA_DOC_LINK_RESOLUTION_FAILURE,
+                NodeId::from_u32(0),
+                sp,
+                &msg,
+            );
             diag.span_label(sp, "cannot be resolved, ignoring");
+            diag
         } else {
-            diag = cx.tcx.struct_span_lint_node(lint::builtin::INTRA_DOC_LINK_RESOLUTION_FAILURE,
-                                                NodeId::from_u32(0),
-                                                sp,
-                                                &msg);
+            let mut diag = cx.tcx.struct_span_lint_node(
+                lint::builtin::INTRA_DOC_LINK_RESOLUTION_FAILURE,
+                NodeId::from_u32(0),
+                sp,
+                &msg,
+            );
 
+            // blah blah blah\nblah\nblah [blah] blah blah\nblah blah
+            //                       ^     ~~~~
+            //                       |     link_range
+            //                       last_new_line_offset
             let last_new_line_offset = dox[..link_range.start].rfind('\n').map_or(0, |n| n + 1);
             let line = dox[last_new_line_offset..].lines().next().unwrap_or("");
 
@@ -522,8 +563,8 @@
                 before=link_range.start - last_new_line_offset,
                 found=link_range.len(),
             ));
+            diag
         }
-        diag
     } else {
         cx.tcx.struct_span_lint_node(lint::builtin::INTRA_DOC_LINK_RESOLUTION_FAILURE,
                                      NodeId::from_u32(0),
diff --git a/src/librustdoc/passes/unindent_comments.rs b/src/librustdoc/passes/unindent_comments.rs
index 6d875c1..5c565bf 100644
--- a/src/librustdoc/passes/unindent_comments.rs
+++ b/src/librustdoc/passes/unindent_comments.rs
@@ -95,7 +95,7 @@
     });
 
     if !lines.is_empty() {
-        let mut unindented = vec![ lines[0].trim_left().to_string() ];
+        let mut unindented = vec![ lines[0].trim_start().to_string() ];
         unindented.extend_from_slice(&lines[1..].iter().map(|&line| {
             if line.chars().all(|c| c.is_whitespace()) {
                 line.to_string()
diff --git a/src/librustdoc/test.rs b/src/librustdoc/test.rs
index be9327c..50acde6 100644
--- a/src/librustdoc/test.rs
+++ b/src/librustdoc/test.rs
@@ -21,7 +21,7 @@
 use rustc::hir::intravisit;
 use rustc::session::{self, CompileIncomplete, config};
 use rustc::session::config::{OutputType, OutputTypes, Externs, CodegenOptions};
-use rustc::session::search_paths::{SearchPaths, PathKind};
+use rustc::session::search_paths::{SearchPath, PathKind};
 use syntax::ast;
 use syntax::source_map::SourceMap;
 use syntax::edition::Edition;
@@ -187,7 +187,7 @@
 }
 
 fn run_test(test: &str, cratename: &str, filename: &FileName, line: usize,
-            cfgs: Vec<String>, libs: SearchPaths,
+            cfgs: Vec<String>, libs: Vec<SearchPath>,
             cg: CodegenOptions, externs: Externs,
             should_panic: bool, no_run: bool, as_test_harness: bool,
             compile_fail: bool, mut error_codes: Vec<String>, opts: &TestOptions,
@@ -556,7 +556,7 @@
     names: Vec<String>,
 
     cfgs: Vec<String>,
-    libs: SearchPaths,
+    libs: Vec<SearchPath>,
     cg: CodegenOptions,
     externs: Externs,
     use_headers: bool,
@@ -571,7 +571,7 @@
 }
 
 impl Collector {
-    pub fn new(cratename: String, cfgs: Vec<String>, libs: SearchPaths, cg: CodegenOptions,
+    pub fn new(cratename: String, cfgs: Vec<String>, libs: Vec<SearchPath>, cg: CodegenOptions,
                externs: Externs, use_headers: bool, opts: TestOptions,
                maybe_sysroot: Option<PathBuf>, source_map: Option<Lrc<SourceMap>>,
                filename: Option<PathBuf>, linker: Option<PathBuf>, edition: Edition) -> Collector {
diff --git a/src/librustdoc/visit_ast.rs b/src/librustdoc/visit_ast.rs
index 004be1c..287984c 100644
--- a/src/librustdoc/visit_ast.rs
+++ b/src/librustdoc/visit_ast.rs
@@ -424,10 +424,11 @@
             hir::ItemKind::Use(ref path, kind) => {
                 let is_glob = kind == hir::UseKind::Glob;
 
-                // Struct and variant constructors always show up alongside their definitions, we've
-                // already processed them so just discard these.
+                // Struct and variant constructors and proc macro stubs always show up alongside
+                // their definitions, we've already processed them so just discard these.
                 match path.def {
-                    Def::StructCtor(..) | Def::VariantCtor(..) | Def::SelfCtor(..) => return,
+                    Def::StructCtor(..) | Def::VariantCtor(..) | Def::SelfCtor(..) |
+                    Def::Macro(_, MacroKind::ProcMacroStub) => return,
                     _ => {}
                 }
 
diff --git a/src/libserialize/json.rs b/src/libserialize/json.rs
index 9439dc7..b0884e1 100644
--- a/src/libserialize/json.rs
+++ b/src/libserialize/json.rs
@@ -3493,7 +3493,7 @@
 
         // Helper function for counting indents
         fn indents(source: &str) -> usize {
-            let trimmed = source.trim_left_matches(' ');
+            let trimmed = source.trim_start_matches(' ');
             source.len() - trimmed.len()
         }
 
diff --git a/src/libstd/Cargo.toml b/src/libstd/Cargo.toml
index 274d5be..41e778b 100644
--- a/src/libstd/Cargo.toml
+++ b/src/libstd/Cargo.toml
@@ -17,13 +17,13 @@
 panic_unwind = { path = "../libpanic_unwind", optional = true }
 panic_abort = { path = "../libpanic_abort" }
 core = { path = "../libcore" }
-libc = { path = "../rustc/libc_shim" }
-compiler_builtins = { path = "../rustc/compiler_builtins_shim" }
+libc = { version = "0.2.44", default-features = false, features = ['rustc-dep-of-std'] }
+compiler_builtins = { version = "0.1.1" }
 profiler_builtins = { path = "../libprofiler_builtins", optional = true }
 unwind = { path = "../libunwind" }
 
 [dev-dependencies]
-rand = "0.5"
+rand = "0.6.1"
 
 [target.x86_64-apple-darwin.dependencies]
 rustc_asan = { path = "../librustc_asan" }
@@ -36,10 +36,10 @@
 rustc_tsan = { path = "../librustc_tsan" }
 
 [target.'cfg(any(all(target_arch = "wasm32", not(target_os = "emscripten")), target_env = "sgx"))'.dependencies]
-dlmalloc = { path = '../rustc/dlmalloc_shim' }
+dlmalloc = { version = "0.1", features = ['rustc-dep-of-std'] }
 
 [target.x86_64-fortanix-unknown-sgx.dependencies]
-fortanix-sgx-abi = { path = "../rustc/fortanix-sgx-abi_shim" }
+fortanix-sgx-abi = { version = "0.3.1", features = ['rustc-dep-of-std'] }
 
 [build-dependencies]
 cc = "1.0"
diff --git a/src/libstd/build.rs b/src/libstd/build.rs
index 9d6e8c4..7143de5 100644
--- a/src/libstd/build.rs
+++ b/src/libstd/build.rs
@@ -68,7 +68,6 @@
         println!("cargo:rustc-link-lib=advapi32");
         println!("cargo:rustc-link-lib=ws2_32");
         println!("cargo:rustc-link-lib=userenv");
-        println!("cargo:rustc-link-lib=shell32");
     } else if target.contains("fuchsia") {
         println!("cargo:rustc-link-lib=zircon");
         println!("cargo:rustc-link-lib=fdio");
@@ -82,7 +81,12 @@
 }
 
 fn build_libbacktrace(target: &str) -> Result<(), ()> {
-    let native = native_lib_boilerplate("libbacktrace", "libbacktrace", "backtrace", "")?;
+    let native = native_lib_boilerplate(
+        "../libbacktrace".as_ref(),
+        "libbacktrace",
+        "backtrace",
+        "",
+    )?;
 
     let mut build = cc::Build::new();
     build
diff --git a/src/libstd/error.rs b/src/libstd/error.rs
index a9b2711..e5c5ab8 100644
--- a/src/libstd/error.rs
+++ b/src/libstd/error.rs
@@ -533,6 +533,7 @@
         Error::description(&**self)
     }
 
+    #[allow(deprecated)]
     fn cause(&self) -> Option<&dyn Error> {
         Error::cause(&**self)
     }
diff --git a/src/libstd/ffi/mod.rs b/src/libstd/ffi/mod.rs
index 99da73a..f46c4f2 100644
--- a/src/libstd/ffi/mod.rs
+++ b/src/libstd/ffi/mod.rs
@@ -174,7 +174,6 @@
 #[stable(feature = "raw_os", since = "1.1.0")]
 pub use core::ffi::c_void;
 
-#[cfg(not(stage0))]
 #[unstable(feature = "c_variadic",
            reason = "the `c_variadic` feature has not been properly tested on \
                      all supported platforms",
diff --git a/src/libstd/ffi/os_str.rs b/src/libstd/ffi/os_str.rs
index 8289721..766142f 100644
--- a/src/libstd/ffi/os_str.rs
+++ b/src/libstd/ffi/os_str.rs
@@ -536,17 +536,42 @@
     ///
     /// # Examples
     ///
-    /// Calling `to_string_lossy` on an `OsStr` with valid unicode:
+    /// Calling `to_string_lossy` on an `OsStr` with invalid unicode:
     ///
     /// ```
-    /// use std::ffi::OsStr;
+    /// // Note, due to differences in how Unix and Windows represent strings,
+    /// // we are forced to complicate this example, setting up example `OsStr`s
+    /// // with different source data and via different platform extensions.
+    /// // Understand that in reality you could end up with such example invalid
+    /// // sequences simply through collecting user command line arguments, for
+    /// // example.
     ///
-    /// let os_str = OsStr::new("foo");
-    /// assert_eq!(os_str.to_string_lossy(), "foo");
+    /// #[cfg(any(unix, target_os = "redox"))] {
+    ///     use std::ffi::OsStr;
+    ///     use std::os::unix::ffi::OsStrExt;
+    ///
+    ///     // Here, the values 0x66 and 0x6f correspond to 'f' and 'o'
+    ///     // respectively. The value 0x80 is a lone continuation byte, invalid
+    ///     // in a UTF-8 sequence.
+    ///     let source = [0x66, 0x6f, 0x80, 0x6f];
+    ///     let os_str = OsStr::from_bytes(&source[..]);
+    ///
+    ///     assert_eq!(os_str.to_string_lossy(), "fo�o");
+    /// }
+    /// #[cfg(windows)] {
+    ///     use std::ffi::OsString;
+    ///     use std::os::windows::prelude::*;
+    ///
+    ///     // Here the values 0x0066 and 0x006f correspond to 'f' and 'o'
+    ///     // respectively. The value 0xD800 is a lone surrogate half, invalid
+    ///     // in a UTF-16 sequence.
+    ///     let source = [0x0066, 0x006f, 0xD800, 0x006f];
+    ///     let os_string = OsString::from_wide(&source[..]);
+    ///     let os_str = os_string.as_os_str();
+    ///
+    ///     assert_eq!(os_str.to_string_lossy(), "fo�o");
+    /// }
     /// ```
-    ///
-    /// Had `os_str` contained invalid unicode, the `to_string_lossy` call might
-    /// have returned `"fo�"`.
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn to_string_lossy(&self) -> Cow<str> {
         self.inner.to_string_lossy()
diff --git a/src/libstd/fs.rs b/src/libstd/fs.rs
index b6a0ce6..d581ba1 100644
--- a/src/libstd/fs.rs
+++ b/src/libstd/fs.rs
@@ -2089,7 +2089,7 @@
     use fs::{self, File, OpenOptions};
     use io::{ErrorKind, SeekFrom};
     use path::Path;
-    use rand::{StdRng, FromEntropy, RngCore};
+    use rand::{rngs::StdRng, FromEntropy, RngCore};
     use str;
     use sys_common::io::test::{TempDir, tmpdir};
     use thread;
diff --git a/src/libstd/io/error.rs b/src/libstd/io/error.rs
index 32e2996..d3844eb 100644
--- a/src/libstd/io/error.rs
+++ b/src/libstd/io/error.rs
@@ -555,6 +555,7 @@
         }
     }
 
+    #[allow(deprecated)]
     fn cause(&self) -> Option<&dyn error::Error> {
         match self.repr {
             Repr::Os(..) => None,
diff --git a/src/libstd/io/lazy.rs b/src/libstd/io/lazy.rs
index c2aaeb9..24965ff 100644
--- a/src/libstd/io/lazy.rs
+++ b/src/libstd/io/lazy.rs
@@ -26,7 +26,6 @@
 unsafe impl<T> Sync for Lazy<T> {}
 
 impl<T> Lazy<T> {
-    #[unstable(feature = "sys_internals", issue = "0")] // FIXME: min_const_fn
     pub const fn new() -> Lazy<T> {
         Lazy {
             lock: Mutex::new(),
diff --git a/src/libstd/lib.rs b/src/libstd/lib.rs
index 90c8eaf..0febbe5 100644
--- a/src/libstd/lib.rs
+++ b/src/libstd/lib.rs
@@ -271,6 +271,7 @@
 #![feature(libc)]
 #![feature(link_args)]
 #![feature(linkage)]
+#![cfg_attr(not(stage0), feature(min_const_unsafe_fn))]
 #![feature(needs_panic_runtime)]
 #![feature(never_type)]
 #![feature(nll)]
@@ -317,10 +318,6 @@
 
 #![default_lib_allocator]
 
-#[cfg(stage0)]
-#[global_allocator]
-static ALLOC: alloc::System = alloc::System;
-
 // Explicitly import the prelude. The compiler uses this same unstable attribute
 // to import the prelude implicitly when building crates that depend on std.
 #[prelude_import]
diff --git a/src/libstd/panic.rs b/src/libstd/panic.rs
index 099b4d6..3eacc7a 100644
--- a/src/libstd/panic.rs
+++ b/src/libstd/panic.rs
@@ -264,7 +264,7 @@
 #[cfg(target_has_atomic = "64")]
 #[unstable(feature = "integer_atomics", issue = "32976")]
 impl RefUnwindSafe for atomic::AtomicI64 {}
-#[cfg(all(not(stage0), target_has_atomic = "128"))]
+#[cfg(target_has_atomic = "128")]
 #[unstable(feature = "integer_atomics", issue = "32976")]
 impl RefUnwindSafe for atomic::AtomicI128 {}
 
@@ -283,7 +283,7 @@
 #[cfg(target_has_atomic = "64")]
 #[unstable(feature = "integer_atomics", issue = "32976")]
 impl RefUnwindSafe for atomic::AtomicU64 {}
-#[cfg(all(not(stage0), target_has_atomic = "128"))]
+#[cfg(target_has_atomic = "128")]
 #[unstable(feature = "integer_atomics", issue = "32976")]
 impl RefUnwindSafe for atomic::AtomicU128 {}
 
diff --git a/src/libstd/panicking.rs b/src/libstd/panicking.rs
index 6b47ba6..b6180fb 100644
--- a/src/libstd/panicking.rs
+++ b/src/libstd/panicking.rs
@@ -209,7 +209,8 @@
             if let Some(format) = log_backtrace {
                 let _ = backtrace::print(err, format);
             } else if FIRST_PANIC.compare_and_swap(true, false, Ordering::SeqCst) {
-                let _ = writeln!(err, "note: Run with `RUST_BACKTRACE=1` for a backtrace.");
+                let _ = writeln!(err, "note: Run with `RUST_BACKTRACE=1` \
+                                       environment variable to display a backtrace.");
             }
         }
     };
diff --git a/src/libstd/primitive_docs.rs b/src/libstd/primitive_docs.rs
index 3b2366a..7c1654f 100644
--- a/src/libstd/primitive_docs.rs
+++ b/src/libstd/primitive_docs.rs
@@ -426,7 +426,7 @@
 /// ## 3. Get it from C.
 ///
 /// ```
-/// # #![feature(libc)]
+/// # #![feature(rustc_private)]
 /// extern crate libc;
 ///
 /// use std::mem;
diff --git a/src/libstd/sys/cloudabi/condvar.rs b/src/libstd/sys/cloudabi/condvar.rs
index ccf848a..3229d98 100644
--- a/src/libstd/sys/cloudabi/condvar.rs
+++ b/src/libstd/sys/cloudabi/condvar.rs
@@ -13,7 +13,7 @@
 use sync::atomic::{AtomicU32, Ordering};
 use sys::cloudabi::abi;
 use sys::mutex::{self, Mutex};
-use sys::time::dur2intervals;
+use sys::time::checked_dur2intervals;
 use time::Duration;
 
 extern "C" {
@@ -114,6 +114,8 @@
 
         // Call into the kernel to wait on the condition variable.
         let condvar = self.condvar.get();
+        let timeout = checked_dur2intervals(&dur)
+            .expect("overflow converting duration to nanoseconds");
         let subscriptions = [
             abi::subscription {
                 type_: abi::eventtype::CONDVAR,
@@ -132,7 +134,7 @@
                 union: abi::subscription_union {
                     clock: abi::subscription_clock {
                         clock_id: abi::clockid::MONOTONIC,
-                        timeout: dur2intervals(&dur),
+                        timeout,
                         ..mem::zeroed()
                     },
                 },
diff --git a/src/libstd/sys/cloudabi/thread.rs b/src/libstd/sys/cloudabi/thread.rs
index a76e1fa..1773214 100644
--- a/src/libstd/sys/cloudabi/thread.rs
+++ b/src/libstd/sys/cloudabi/thread.rs
@@ -16,7 +16,7 @@
 use mem;
 use ptr;
 use sys::cloudabi::abi;
-use sys::time::dur2intervals;
+use sys::time::checked_dur2intervals;
 use sys_common::thread::*;
 use time::Duration;
 
@@ -70,13 +70,15 @@
     }
 
     pub fn sleep(dur: Duration) {
+        let timeout = checked_dur2intervals(&dur)
+            .expect("overflow converting duration to nanoseconds");
         unsafe {
             let subscription = abi::subscription {
                 type_: abi::eventtype::CLOCK,
                 union: abi::subscription_union {
                     clock: abi::subscription_clock {
                         clock_id: abi::clockid::MONOTONIC,
-                        timeout: dur2intervals(&dur),
+                        timeout,
                         ..mem::zeroed()
                     },
                 },
diff --git a/src/libstd/sys/cloudabi/time.rs b/src/libstd/sys/cloudabi/time.rs
index a442d1e..c9fea18 100644
--- a/src/libstd/sys/cloudabi/time.rs
+++ b/src/libstd/sys/cloudabi/time.rs
@@ -19,15 +19,10 @@
     t: abi::timestamp,
 }
 
-fn checked_dur2intervals(dur: &Duration) -> Option<abi::timestamp> {
+pub fn checked_dur2intervals(dur: &Duration) -> Option<abi::timestamp> {
     dur.as_secs()
-        .checked_mul(NSEC_PER_SEC)
-        .and_then(|nanos| nanos.checked_add(dur.subsec_nanos() as abi::timestamp))
-}
-
-pub fn dur2intervals(dur: &Duration) -> abi::timestamp {
-    checked_dur2intervals(dur)
-        .expect("overflow converting duration to nanoseconds")
+        .checked_mul(NSEC_PER_SEC)?
+        .checked_add(dur.subsec_nanos() as abi::timestamp)
 }
 
 impl Instant {
@@ -47,20 +42,16 @@
         Duration::new(diff / NSEC_PER_SEC, (diff % NSEC_PER_SEC) as u32)
     }
 
-    pub fn add_duration(&self, other: &Duration) -> Instant {
-        Instant {
-            t: self.t
-                .checked_add(dur2intervals(other))
-                .expect("overflow when adding duration to instant"),
-        }
+    pub fn checked_add_duration(&self, other: &Duration) -> Option<Instant> {
+        Some(Instant {
+            t: self.t.checked_add(checked_dur2intervals(other)?)?,
+        })
     }
 
-    pub fn sub_duration(&self, other: &Duration) -> Instant {
-        Instant {
-            t: self.t
-                .checked_sub(dur2intervals(other))
-                .expect("overflow when subtracting duration from instant"),
-        }
+    pub fn checked_sub_duration(&self, other: &Duration) -> Option<Instant> {
+        Some(Instant {
+            t: self.t.checked_sub(checked_dur2intervals(other)?)?,
+        })
     }
 }
 
@@ -95,23 +86,16 @@
         }
     }
 
-    pub fn add_duration(&self, other: &Duration) -> SystemTime {
-        self.checked_add_duration(other)
-            .expect("overflow when adding duration to instant")
-    }
-
     pub fn checked_add_duration(&self, other: &Duration) -> Option<SystemTime> {
-        checked_dur2intervals(other)
-            .and_then(|d| self.t.checked_add(d))
-            .map(|t| SystemTime {t})
+        Some(SystemTime {
+            t: self.t.checked_add(checked_dur2intervals(other)?)?,
+        })
     }
 
-    pub fn sub_duration(&self, other: &Duration) -> SystemTime {
-        SystemTime {
-            t: self.t
-                .checked_sub(dur2intervals(other))
-                .expect("overflow when subtracting duration from instant"),
-        }
+    pub fn checked_sub_duration(&self, other: &Duration) -> Option<SystemTime> {
+        Some(SystemTime {
+            t: self.t.checked_sub(checked_dur2intervals(other)?)?,
+        })
     }
 }
 
diff --git a/src/libstd/sys/redox/time.rs b/src/libstd/sys/redox/time.rs
index beff8d2..cb2eab5 100644
--- a/src/libstd/sys/redox/time.rs
+++ b/src/libstd/sys/redox/time.rs
@@ -41,10 +41,6 @@
         }
     }
 
-    fn add_duration(&self, other: &Duration) -> Timespec {
-        self.checked_add_duration(other).expect("overflow when adding duration to time")
-    }
-
     fn checked_add_duration(&self, other: &Duration) -> Option<Timespec> {
         let mut secs = other
             .as_secs()
@@ -67,27 +63,25 @@
         })
     }
 
-    fn sub_duration(&self, other: &Duration) -> Timespec {
+    fn checked_sub_duration(&self, other: &Duration) -> Option<Timespec> {
         let mut secs = other
             .as_secs()
             .try_into() // <- target type would be `i64`
             .ok()
-            .and_then(|secs| self.t.tv_sec.checked_sub(secs))
-            .expect("overflow when subtracting duration from time");
+            .and_then(|secs| self.t.tv_sec.checked_sub(secs))?;
 
         // Similar to above, nanos can't overflow.
         let mut nsec = self.t.tv_nsec as i32 - other.subsec_nanos() as i32;
         if nsec < 0 {
             nsec += NSEC_PER_SEC as i32;
-            secs = secs.checked_sub(1).expect("overflow when subtracting \
-                                               duration from time");
+            secs = secs.checked_sub(1)?;
         }
-        Timespec {
+        Some(Timespec {
             t: syscall::TimeSpec {
                 tv_sec: secs,
                 tv_nsec: nsec as i32,
             },
-        }
+        })
     }
 }
 
@@ -150,12 +144,12 @@
         })
     }
 
-    pub fn add_duration(&self, other: &Duration) -> Instant {
-        Instant { t: self.t.add_duration(other) }
+    pub fn checked_add_duration(&self, other: &Duration) -> Option<Instant> {
+        Some(Instant { t: self.t.checked_add_duration(other)? })
     }
 
-    pub fn sub_duration(&self, other: &Duration) -> Instant {
-        Instant { t: self.t.sub_duration(other) }
+    pub fn checked_sub_duration(&self, other: &Duration) -> Option<Instant> {
+        Some(Instant { t: self.t.checked_sub_duration(other)? })
     }
 }
 
@@ -178,16 +172,12 @@
         self.t.sub_timespec(&other.t)
     }
 
-    pub fn add_duration(&self, other: &Duration) -> SystemTime {
-        SystemTime { t: self.t.add_duration(other) }
-    }
-
     pub fn checked_add_duration(&self, other: &Duration) -> Option<SystemTime> {
-        self.t.checked_add_duration(other).map(|t| SystemTime { t })
+        Some(SystemTime { t: self.t.checked_add_duration(other)? })
     }
 
-    pub fn sub_duration(&self, other: &Duration) -> SystemTime {
-        SystemTime { t: self.t.sub_duration(other) }
+    pub fn checked_sub_duration(&self, other: &Duration) -> Option<SystemTime> {
+        Some(SystemTime { t: self.t.checked_sub_duration(other)? })
     }
 }
 
diff --git a/src/libstd/sys/sgx/abi/mem.rs b/src/libstd/sys/sgx/abi/mem.rs
index 508f2ff..bf32c71 100644
--- a/src/libstd/sys/sgx/abi/mem.rs
+++ b/src/libstd/sys/sgx/abi/mem.rs
@@ -34,13 +34,6 @@
     base
 }
 
-pub fn is_enclave_range(p: *const u8, len: usize) -> bool {
-    let start=p as u64;
-    let end=start + (len as u64);
-    start >= image_base() &&
-        end <= image_base() + (unsafe { ENCLAVE_SIZE } as u64) // unsafe ok: link-time constant
-}
-
 pub fn is_user_range(p: *const u8, len: usize) -> bool {
     let start=p as u64;
     let end=start + (len as u64);
diff --git a/src/libstd/sys/sgx/abi/usercalls/mod.rs b/src/libstd/sys/sgx/abi/usercalls/mod.rs
index 2bc32c9..d1d180e 100644
--- a/src/libstd/sys/sgx/abi/usercalls/mod.rs
+++ b/src/libstd/sys/sgx/abi/usercalls/mod.rs
@@ -33,14 +33,6 @@
     }
 }
 
-pub fn read_alloc(fd: Fd) -> IoResult<Vec<u8>> {
-    unsafe {
-        let mut userbuf = alloc::User::<ByteBuffer>::uninitialized();
-        raw::read_alloc(fd, userbuf.as_raw_mut_ptr()).from_sgx_result()?;
-        Ok(copy_user_buffer(&userbuf))
-    }
-}
-
 pub fn write(fd: Fd, buf: &[u8]) -> IoResult<usize> {
     unsafe {
         let userbuf = alloc::User::new_from_enclave(buf);
diff --git a/src/libstd/sys/sgx/condvar.rs b/src/libstd/sys/sgx/condvar.rs
index d3e8165..940f50f 100644
--- a/src/libstd/sys/sgx/condvar.rs
+++ b/src/libstd/sys/sgx/condvar.rs
@@ -18,7 +18,6 @@
 }
 
 impl Condvar {
-    #[unstable(feature = "sgx_internals", issue = "0")] // FIXME: min_const_fn
     pub const fn new() -> Condvar {
         Condvar { inner: SpinMutex::new(WaitVariable::new(())) }
     }
diff --git a/src/libstd/sys/sgx/mutex.rs b/src/libstd/sys/sgx/mutex.rs
index 6633611..994cf91 100644
--- a/src/libstd/sys/sgx/mutex.rs
+++ b/src/libstd/sys/sgx/mutex.rs
@@ -20,7 +20,6 @@
 
 // Implementation according to “Operating Systems: Three Easy Pieces”, chapter 28
 impl Mutex {
-    #[unstable(feature = "sgx_internals", issue = "0")] // FIXME: min_const_fn
     pub const fn new() -> Mutex {
         Mutex { inner: SpinMutex::new(WaitVariable::new(false)) }
     }
@@ -79,7 +78,6 @@
 }
 
 impl ReentrantMutex {
-    #[unstable(feature = "sgx_internals", issue = "0")] // FIXME: min_const_fn
     pub const fn uninitialized() -> ReentrantMutex {
         ReentrantMutex {
             inner: SpinMutex::new(WaitVariable::new(ReentrantLock { owner: None, count: 0 }))
diff --git a/src/libstd/sys/sgx/rwlock.rs b/src/libstd/sys/sgx/rwlock.rs
index 7b6970b..a1551db 100644
--- a/src/libstd/sys/sgx/rwlock.rs
+++ b/src/libstd/sys/sgx/rwlock.rs
@@ -21,7 +21,6 @@
 //unsafe impl Sync for RWLock {} // FIXME
 
 impl RWLock {
-    #[unstable(feature = "sgx_internals", issue = "0")] // FIXME: min_const_fn
     pub const fn new() -> RWLock {
         RWLock {
             readers: SpinMutex::new(WaitVariable::new(None)),
diff --git a/src/libstd/sys/sgx/time.rs b/src/libstd/sys/sgx/time.rs
index b01c992..196e1a9 100644
--- a/src/libstd/sys/sgx/time.rs
+++ b/src/libstd/sys/sgx/time.rs
@@ -28,12 +28,12 @@
         self.0 - other.0
     }
 
-    pub fn add_duration(&self, other: &Duration) -> Instant {
-        Instant(self.0 + *other)
+    pub fn checked_add_duration(&self, other: &Duration) -> Option<Instant> {
+        Some(Instant(self.0.checked_add(*other)?))
     }
 
-    pub fn sub_duration(&self, other: &Duration) -> Instant {
-        Instant(self.0 - *other)
+    pub fn checked_sub_duration(&self, other: &Duration) -> Option<Instant> {
+        Some(Instant(self.0.checked_sub(*other)?))
     }
 }
 
@@ -47,15 +47,11 @@
         self.0.checked_sub(other.0).ok_or_else(|| other.0 - self.0)
     }
 
-    pub fn add_duration(&self, other: &Duration) -> SystemTime {
-        SystemTime(self.0 + *other)
-    }
-
     pub fn checked_add_duration(&self, other: &Duration) -> Option<SystemTime> {
-        self.0.checked_add(*other).map(|d| SystemTime(d))
+        Some(SystemTime(self.0.checked_add(*other)?))
     }
 
-    pub fn sub_duration(&self, other: &Duration) -> SystemTime {
-        SystemTime(self.0 - *other)
+    pub fn checked_sub_duration(&self, other: &Duration) -> Option<SystemTime> {
+        Some(SystemTime(self.0.checked_sub(*other)?))
     }
 }
diff --git a/src/libstd/sys/sgx/waitqueue.rs b/src/libstd/sys/sgx/waitqueue.rs
index ec1135b..ef0def1 100644
--- a/src/libstd/sys/sgx/waitqueue.rs
+++ b/src/libstd/sys/sgx/waitqueue.rs
@@ -50,7 +50,6 @@
 }
 
 impl<T> WaitVariable<T> {
-    #[unstable(feature = "sgx_internals", issue = "0")] // FIXME: min_const_fn
     pub const fn new(var: T) -> Self {
         WaitVariable {
             queue: WaitQueue::new(),
@@ -137,7 +136,6 @@
 }
 
 impl WaitQueue {
-    #[unstable(feature = "sgx_internals", issue = "0")] // FIXME: min_const_fn
     pub const fn new() -> Self {
         WaitQueue {
             inner: UnsafeList::new()
@@ -255,7 +253,6 @@
     }
 
     impl<T> UnsafeList<T> {
-        #[unstable(feature = "sgx_internals", issue = "0")] // FIXME: min_const_fn
         pub const fn new() -> Self {
             unsafe {
                 UnsafeList {
diff --git a/src/libstd/sys/unix/ext/fs.rs b/src/libstd/sys/unix/ext/fs.rs
index 7e65bbd..af2f199 100644
--- a/src/libstd/sys/unix/ext/fs.rs
+++ b/src/libstd/sys/unix/ext/fs.rs
@@ -348,7 +348,7 @@
     /// # Examples
     ///
     /// ```no_run
-    /// # #![feature(libc)]
+    /// # #![feature(rustc_private)]
     /// extern crate libc;
     /// use std::fs::OpenOptions;
     /// use std::os::unix::fs::OpenOptionsExt;
diff --git a/src/libstd/sys/unix/time.rs b/src/libstd/sys/unix/time.rs
index 1f9539c..8f8aaa8 100644
--- a/src/libstd/sys/unix/time.rs
+++ b/src/libstd/sys/unix/time.rs
@@ -42,10 +42,6 @@
         }
     }
 
-    fn add_duration(&self, other: &Duration) -> Timespec {
-        self.checked_add_duration(other).expect("overflow when adding duration to time")
-    }
-
     fn checked_add_duration(&self, other: &Duration) -> Option<Timespec> {
         let mut secs = other
             .as_secs()
@@ -68,27 +64,25 @@
         })
     }
 
-    fn sub_duration(&self, other: &Duration) -> Timespec {
+    fn checked_sub_duration(&self, other: &Duration) -> Option<Timespec> {
         let mut secs = other
             .as_secs()
             .try_into() // <- target type would be `libc::time_t`
             .ok()
-            .and_then(|secs| self.t.tv_sec.checked_sub(secs))
-            .expect("overflow when subtracting duration from time");
+            .and_then(|secs| self.t.tv_sec.checked_sub(secs))?;
 
         // Similar to above, nanos can't overflow.
         let mut nsec = self.t.tv_nsec as i32 - other.subsec_nanos() as i32;
         if nsec < 0 {
             nsec += NSEC_PER_SEC as i32;
-            secs = secs.checked_sub(1).expect("overflow when subtracting \
-                                               duration from time");
+            secs = secs.checked_sub(1)?;
         }
-        Timespec {
+        Some(Timespec {
             t: libc::timespec {
                 tv_sec: secs,
                 tv_nsec: nsec as _,
             },
-        }
+        })
     }
 }
 
@@ -165,18 +159,16 @@
             Duration::new(nanos / NSEC_PER_SEC, (nanos % NSEC_PER_SEC) as u32)
         }
 
-        pub fn add_duration(&self, other: &Duration) -> Instant {
-            Instant {
-                t: self.t.checked_add(dur2intervals(other))
-                       .expect("overflow when adding duration to instant"),
-            }
+        pub fn checked_add_duration(&self, other: &Duration) -> Option<Instant> {
+            Some(Instant {
+                t: self.t.checked_add(checked_dur2intervals(other)?)?,
+            })
         }
 
-        pub fn sub_duration(&self, other: &Duration) -> Instant {
-            Instant {
-                t: self.t.checked_sub(dur2intervals(other))
-                       .expect("overflow when subtracting duration from instant"),
-            }
+        pub fn checked_sub_duration(&self, other: &Duration) -> Option<Instant> {
+            Some(Instant {
+                t: self.t.checked_sub(checked_dur2intervals(other)?)?,
+            })
         }
     }
 
@@ -199,16 +191,12 @@
             self.t.sub_timespec(&other.t)
         }
 
-        pub fn add_duration(&self, other: &Duration) -> SystemTime {
-            SystemTime { t: self.t.add_duration(other) }
-        }
-
         pub fn checked_add_duration(&self, other: &Duration) -> Option<SystemTime> {
-            self.t.checked_add_duration(other).map(|t| SystemTime { t })
+            Some(SystemTime { t: self.t.checked_add_duration(other)? })
         }
 
-        pub fn sub_duration(&self, other: &Duration) -> SystemTime {
-            SystemTime { t: self.t.sub_duration(other) }
+        pub fn checked_sub_duration(&self, other: &Duration) -> Option<SystemTime> {
+            Some(SystemTime { t: self.t.checked_sub_duration(other)? })
         }
     }
 
@@ -236,12 +224,12 @@
         }
     }
 
-    fn dur2intervals(dur: &Duration) -> u64 {
+    fn checked_dur2intervals(dur: &Duration) -> Option<u64> {
+        let nanos = dur.as_secs()
+            .checked_mul(NSEC_PER_SEC)?
+            .checked_add(dur.subsec_nanos() as u64)?;
         let info = info();
-        let nanos = dur.as_secs().checked_mul(NSEC_PER_SEC).and_then(|nanos| {
-            nanos.checked_add(dur.subsec_nanos() as u64)
-        }).expect("overflow converting duration to nanoseconds");
-        mul_div_u64(nanos, info.denom as u64, info.numer as u64)
+        Some(mul_div_u64(nanos, info.denom as u64, info.numer as u64))
     }
 
     fn info() -> &'static libc::mach_timebase_info {
@@ -299,12 +287,12 @@
             })
         }
 
-        pub fn add_duration(&self, other: &Duration) -> Instant {
-            Instant { t: self.t.add_duration(other) }
+        pub fn checked_add_duration(&self, other: &Duration) -> Option<Instant> {
+            Some(Instant { t: self.t.checked_add_duration(other)? })
         }
 
-        pub fn sub_duration(&self, other: &Duration) -> Instant {
-            Instant { t: self.t.sub_duration(other) }
+        pub fn checked_sub_duration(&self, other: &Duration) -> Option<Instant> {
+            Some(Instant { t: self.t.checked_sub_duration(other)? })
         }
     }
 
@@ -327,16 +315,12 @@
             self.t.sub_timespec(&other.t)
         }
 
-        pub fn add_duration(&self, other: &Duration) -> SystemTime {
-            SystemTime { t: self.t.add_duration(other) }
-        }
-
         pub fn checked_add_duration(&self, other: &Duration) -> Option<SystemTime> {
-            self.t.checked_add_duration(other).map(|t| SystemTime { t })
+            Some(SystemTime { t: self.t.checked_add_duration(other)? })
         }
 
-        pub fn sub_duration(&self, other: &Duration) -> SystemTime {
-            SystemTime { t: self.t.sub_duration(other) }
+        pub fn checked_sub_duration(&self, other: &Duration) -> Option<SystemTime> {
+            Some(SystemTime { t: self.t.checked_sub_duration(other)? })
         }
     }
 
diff --git a/src/libstd/sys/wasm/time.rs b/src/libstd/sys/wasm/time.rs
index 991e817..cc56773 100644
--- a/src/libstd/sys/wasm/time.rs
+++ b/src/libstd/sys/wasm/time.rs
@@ -28,12 +28,12 @@
         self.0 - other.0
     }
 
-    pub fn add_duration(&self, other: &Duration) -> Instant {
-        Instant(self.0 + *other)
+    pub fn checked_add_duration(&self, other: &Duration) -> Option<Instant> {
+        Some(Instant(self.0.checked_add(*other)?))
     }
 
-    pub fn sub_duration(&self, other: &Duration) -> Instant {
-        Instant(self.0 - *other)
+    pub fn checked_sub_duration(&self, other: &Duration) -> Option<Instant> {
+        Some(Instant(self.0.checked_sub(*other)?))
     }
 }
 
@@ -47,15 +47,11 @@
         self.0.checked_sub(other.0).ok_or_else(|| other.0 - self.0)
     }
 
-    pub fn add_duration(&self, other: &Duration) -> SystemTime {
-        SystemTime(self.0 + *other)
-    }
-
     pub fn checked_add_duration(&self, other: &Duration) -> Option<SystemTime> {
-        self.0.checked_add(*other).map(|d| SystemTime(d))
+        Some(SystemTime(self.0.checked_add(*other)?))
     }
 
-    pub fn sub_duration(&self, other: &Duration) -> SystemTime {
-        SystemTime(self.0 - *other)
+    pub fn checked_sub_duration(&self, other: &Duration) -> Option<SystemTime> {
+        Some(SystemTime(self.0.checked_sub(*other)?))
     }
 }
diff --git a/src/libstd/sys/windows/args.rs b/src/libstd/sys/windows/args.rs
index 4784633..9e9198e 100644
--- a/src/libstd/sys/windows/args.rs
+++ b/src/libstd/sys/windows/args.rs
@@ -11,12 +11,14 @@
 #![allow(dead_code)] // runtime init functions not used during testing
 
 use os::windows::prelude::*;
+use sys::windows::os::current_exe;
 use sys::c;
-use slice;
-use ops::Range;
 use ffi::OsString;
-use libc::{c_int, c_void};
 use fmt;
+use vec;
+use core::iter;
+use slice;
+use path::PathBuf;
 
 pub unsafe fn init(_argc: isize, _argv: *const *const u8) { }
 
@@ -24,20 +26,146 @@
 
 pub fn args() -> Args {
     unsafe {
-        let mut nArgs: c_int = 0;
-        let lpCmdLine = c::GetCommandLineW();
-        let szArgList = c::CommandLineToArgvW(lpCmdLine, &mut nArgs);
+        let lp_cmd_line = c::GetCommandLineW();
+        let parsed_args_list = parse_lp_cmd_line(
+            lp_cmd_line as *const u16,
+            || current_exe().map(PathBuf::into_os_string).unwrap_or_else(|_| OsString::new()));
 
-        // szArcList can be NULL if CommandLinToArgvW failed,
-        // but in that case nArgs is 0 so we won't actually
-        // try to read a null pointer
-        Args { cur: szArgList, range: 0..(nArgs as isize) }
+        Args { parsed_args_list: parsed_args_list.into_iter() }
     }
 }
 
+/// Implements the Windows command-line argument parsing algorithm.
+///
+/// Microsoft's documentation for the Windows CLI argument format can be found at
+/// <https://docs.microsoft.com/en-us/previous-versions//17w5ykft(v=vs.85)>.
+///
+/// Windows includes a function to do this in shell32.dll,
+/// but linking with that DLL causes the process to be registered as a GUI application.
+/// GUI applications add a bunch of overhead, even if no windows are drawn. See
+/// <https://randomascii.wordpress.com/2018/12/03/a-not-called-function-can-cause-a-5x-slowdown/>.
+///
+/// This function was tested for equivalence to the shell32.dll implementation in
+/// Windows 10 Pro v1803, using an exhaustive test suite available at
+/// <https://gist.github.com/notriddle/dde431930c392e428055b2dc22e638f5> or
+/// <https://paste.gg/p/anonymous/47d6ed5f5bd549168b1c69c799825223>.
+unsafe fn parse_lp_cmd_line<F: Fn() -> OsString>(lp_cmd_line: *const u16, exe_name: F)
+                                                 -> Vec<OsString> {
+    const BACKSLASH: u16 = '\\' as u16;
+    const QUOTE: u16 = '"' as u16;
+    const TAB: u16 = '\t' as u16;
+    const SPACE: u16 = ' ' as u16;
+    let mut ret_val = Vec::new();
+    if lp_cmd_line.is_null() || *lp_cmd_line == 0 {
+        ret_val.push(exe_name());
+        return ret_val;
+    }
+    let mut cmd_line = {
+        let mut end = 0;
+        while *lp_cmd_line.offset(end) != 0 {
+            end += 1;
+        }
+        slice::from_raw_parts(lp_cmd_line, end as usize)
+    };
+    // The executable name at the beginning is special.
+    cmd_line = match cmd_line[0] {
+        // The executable name ends at the next quote mark,
+        // no matter what.
+        QUOTE => {
+            let args = {
+                let mut cut = cmd_line[1..].splitn(2, |&c| c == QUOTE);
+                if let Some(exe) = cut.next() {
+                    ret_val.push(OsString::from_wide(exe));
+                }
+                cut.next()
+            };
+            if let Some(args) = args {
+                args
+            } else {
+                return ret_val;
+            }
+        }
+        // Implement quirk: when they say whitespace here,
+        // they include the entire ASCII control plane:
+        // "However, if lpCmdLine starts with any amount of whitespace, CommandLineToArgvW
+        // will consider the first argument to be an empty string. Excess whitespace at the
+        // end of lpCmdLine is ignored."
+        0...SPACE => {
+            ret_val.push(OsString::new());
+            &cmd_line[1..]
+        },
+        // The executable name ends at the next whitespace,
+        // no matter what.
+        _ => {
+            let args = {
+                let mut cut = cmd_line.splitn(2, |&c| c > 0 && c <= SPACE);
+                if let Some(exe) = cut.next() {
+                    ret_val.push(OsString::from_wide(exe));
+                }
+                cut.next()
+            };
+            if let Some(args) = args {
+                args
+            } else {
+                return ret_val;
+            }
+        }
+    };
+    let mut cur = Vec::new();
+    let mut in_quotes = false;
+    let mut was_in_quotes = false;
+    let mut backslash_count: usize = 0;
+    for &c in cmd_line {
+        match c {
+            // backslash
+            BACKSLASH => {
+                backslash_count += 1;
+                was_in_quotes = false;
+            },
+            QUOTE if backslash_count % 2 == 0 => {
+                cur.extend(iter::repeat(b'\\' as u16).take(backslash_count / 2));
+                backslash_count = 0;
+                if was_in_quotes {
+                    cur.push('"' as u16);
+                    was_in_quotes = false;
+                } else {
+                    was_in_quotes = in_quotes;
+                    in_quotes = !in_quotes;
+                }
+            }
+            QUOTE if backslash_count % 2 != 0 => {
+                cur.extend(iter::repeat(b'\\' as u16).take(backslash_count / 2));
+                backslash_count = 0;
+                was_in_quotes = false;
+                cur.push(b'"' as u16);
+            }
+            SPACE | TAB if !in_quotes => {
+                cur.extend(iter::repeat(b'\\' as u16).take(backslash_count));
+                if !cur.is_empty() || was_in_quotes {
+                    ret_val.push(OsString::from_wide(&cur[..]));
+                    cur.truncate(0);
+                }
+                backslash_count = 0;
+                was_in_quotes = false;
+            }
+            _ => {
+                cur.extend(iter::repeat(b'\\' as u16).take(backslash_count));
+                backslash_count = 0;
+                was_in_quotes = false;
+                cur.push(c);
+            }
+        }
+    }
+    cur.extend(iter::repeat(b'\\' as u16).take(backslash_count));
+    // include empty quoted strings at the end of the arguments list
+    if !cur.is_empty() || was_in_quotes || in_quotes {
+        ret_val.push(OsString::from_wide(&cur[..]));
+    }
+    ret_val
+}
+
 pub struct Args {
-    range: Range<isize>,
-    cur: *mut *mut u16,
+    parsed_args_list: vec::IntoIter<OsString>,
 }
 
 pub struct ArgsInnerDebug<'a> {
@@ -46,19 +174,7 @@
 
 impl<'a> fmt::Debug for ArgsInnerDebug<'a> {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        f.write_str("[")?;
-        let mut first = true;
-        for i in self.args.range.clone() {
-            if !first {
-                f.write_str(", ")?;
-            }
-            first = false;
-
-            // Here we do allocation which could be avoided.
-            fmt::Debug::fmt(&unsafe { os_string_from_ptr(*self.args.cur.offset(i)) }, f)?;
-        }
-        f.write_str("]")?;
-        Ok(())
+        self.args.parsed_args_list.as_slice().fmt(f)
     }
 }
 
@@ -70,38 +186,82 @@
     }
 }
 
-unsafe fn os_string_from_ptr(ptr: *mut u16) -> OsString {
-    let mut len = 0;
-    while *ptr.offset(len) != 0 { len += 1; }
-
-    // Push it onto the list.
-    let ptr = ptr as *const u16;
-    let buf = slice::from_raw_parts(ptr, len as usize);
-    OsStringExt::from_wide(buf)
-}
-
 impl Iterator for Args {
     type Item = OsString;
-    fn next(&mut self) -> Option<OsString> {
-        self.range.next().map(|i| unsafe { os_string_from_ptr(*self.cur.offset(i)) } )
-    }
-    fn size_hint(&self) -> (usize, Option<usize>) { self.range.size_hint() }
+    fn next(&mut self) -> Option<OsString> { self.parsed_args_list.next() }
+    fn size_hint(&self) -> (usize, Option<usize>) { self.parsed_args_list.size_hint() }
 }
 
 impl DoubleEndedIterator for Args {
-    fn next_back(&mut self) -> Option<OsString> {
-        self.range.next_back().map(|i| unsafe { os_string_from_ptr(*self.cur.offset(i)) } )
-    }
+    fn next_back(&mut self) -> Option<OsString> { self.parsed_args_list.next_back() }
 }
 
 impl ExactSizeIterator for Args {
-    fn len(&self) -> usize { self.range.len() }
+    fn len(&self) -> usize { self.parsed_args_list.len() }
 }
 
-impl Drop for Args {
-    fn drop(&mut self) {
-        // self.cur can be null if CommandLineToArgvW previously failed,
-        // but LocalFree ignores NULL pointers
-        unsafe { c::LocalFree(self.cur as *mut c_void); }
+#[cfg(test)]
+mod tests {
+    use sys::windows::args::*;
+    use ffi::OsString;
+
+    fn chk(string: &str, parts: &[&str]) {
+        let mut wide: Vec<u16> = OsString::from(string).encode_wide().collect();
+        wide.push(0);
+        let parsed = unsafe {
+            parse_lp_cmd_line(wide.as_ptr() as *const u16, || OsString::from("TEST.EXE"))
+        };
+        let expected: Vec<OsString> = parts.iter().map(|k| OsString::from(k)).collect();
+        assert_eq!(parsed.as_slice(), expected.as_slice());
+    }
+
+    #[test]
+    fn empty() {
+        chk("", &["TEST.EXE"]);
+        chk("\0", &["TEST.EXE"]);
+    }
+
+    #[test]
+    fn single_words() {
+        chk("EXE one_word", &["EXE", "one_word"]);
+        chk("EXE a", &["EXE", "a"]);
+        chk("EXE 😅", &["EXE", "😅"]);
+        chk("EXE 😅🤦", &["EXE", "😅🤦"]);
+    }
+
+    #[test]
+    fn official_examples() {
+        chk(r#"EXE "abc" d e"#, &["EXE", "abc", "d", "e"]);
+        chk(r#"EXE a\\\b d"e f"g h"#, &["EXE", r#"a\\\b"#, "de fg", "h"]);
+        chk(r#"EXE a\\\"b c d"#, &["EXE", r#"a\"b"#, "c", "d"]);
+        chk(r#"EXE a\\\\"b c" d e"#, &["EXE", r#"a\\b c"#, "d", "e"]);
+    }
+
+    #[test]
+    fn whitespace_behavior() {
+        chk(r#" test"#, &["", "test"]);
+        chk(r#"  test"#, &["", "test"]);
+        chk(r#" test test2"#, &["", "test", "test2"]);
+        chk(r#" test  test2"#, &["", "test", "test2"]);
+        chk(r#"test test2 "#, &["test", "test2"]);
+        chk(r#"test  test2 "#, &["test", "test2"]);
+        chk(r#"test "#, &["test"]);
+    }
+
+    #[test]
+    fn genius_quotes() {
+        chk(r#"EXE "" """#, &["EXE", "", ""]);
+        chk(r#"EXE "" """"#, &["EXE", "", "\""]);
+        chk(
+            r#"EXE "this is """all""" in the same argument""#,
+            &["EXE", "this is \"all\" in the same argument"]
+        );
+        chk(r#"EXE "a"""#, &["EXE", "a\""]);
+        chk(r#"EXE "a"" a"#, &["EXE", "a\"", "a"]);
+        // quotes cannot be escaped in command names
+        chk(r#""EXE" check"#, &["EXE", "check"]);
+        chk(r#""EXE check""#, &["EXE check"]);
+        chk(r#""EXE """for""" check"#, &["EXE ", r#"for""#, "check"]);
+        chk(r#""EXE \"for\" check"#, &[r#"EXE \"#, r#"for""#,  "check"]);
     }
 }
diff --git a/src/libstd/sys/windows/c.rs b/src/libstd/sys/windows/c.rs
index c84874a..fa21f45 100644
--- a/src/libstd/sys/windows/c.rs
+++ b/src/libstd/sys/windows/c.rs
@@ -1035,9 +1035,6 @@
 
     pub fn SetLastError(dwErrCode: DWORD);
     pub fn GetCommandLineW() -> *mut LPCWSTR;
-    pub fn LocalFree(ptr: *mut c_void);
-    pub fn CommandLineToArgvW(lpCmdLine: *mut LPCWSTR,
-                              pNumArgs: *mut c_int) -> *mut *mut u16;
     pub fn GetTempPathW(nBufferLength: DWORD,
                         lpBuffer: LPCWSTR) -> DWORD;
     pub fn OpenProcessToken(ProcessHandle: HANDLE,
diff --git a/src/libstd/sys/windows/os.rs b/src/libstd/sys/windows/os.rs
index 2be30e6..84ef62e 100644
--- a/src/libstd/sys/windows/os.rs
+++ b/src/libstd/sys/windows/os.rs
@@ -76,7 +76,7 @@
         match String::from_utf16(&buf[..res]) {
             Ok(mut msg) => {
                 // Trim trailing CRLF inserted by FormatMessageW
-                let len = msg.trim_right().len();
+                let len = msg.trim_end().len();
                 msg.truncate(len);
                 msg
             },
diff --git a/src/libstd/sys/windows/time.rs b/src/libstd/sys/windows/time.rs
index c809a0b..bb2c97e 100644
--- a/src/libstd/sys/windows/time.rs
+++ b/src/libstd/sys/windows/time.rs
@@ -68,30 +68,27 @@
         Duration::new(nanos / NANOS_PER_SEC, (nanos % NANOS_PER_SEC) as u32)
     }
 
-    pub fn add_duration(&self, other: &Duration) -> Instant {
+    pub fn checked_add_duration(&self, other: &Duration) -> Option<Instant> {
         let freq = frequency() as u64;
-        let t = other.as_secs().checked_mul(freq).and_then(|i| {
-            (self.t as u64).checked_add(i)
-        }).and_then(|i| {
-            i.checked_add(mul_div_u64(other.subsec_nanos() as u64, freq,
-                                      NANOS_PER_SEC))
-        }).expect("overflow when adding duration to time");
-        Instant {
+        let t = other.as_secs()
+            .checked_mul(freq)?
+            .checked_add(mul_div_u64(other.subsec_nanos() as u64, freq, NANOS_PER_SEC))?
+            .checked_add(self.t as u64)?;
+        Some(Instant {
             t: t as c::LARGE_INTEGER,
-        }
+        })
     }
 
-    pub fn sub_duration(&self, other: &Duration) -> Instant {
+    pub fn checked_sub_duration(&self, other: &Duration) -> Option<Instant> {
         let freq = frequency() as u64;
         let t = other.as_secs().checked_mul(freq).and_then(|i| {
             (self.t as u64).checked_sub(i)
         }).and_then(|i| {
-            i.checked_sub(mul_div_u64(other.subsec_nanos() as u64, freq,
-                                      NANOS_PER_SEC))
-        }).expect("overflow when subtracting duration from time");
-        Instant {
+            i.checked_sub(mul_div_u64(other.subsec_nanos() as u64, freq, NANOS_PER_SEC))
+        })?;
+        Some(Instant {
             t: t as c::LARGE_INTEGER,
-        }
+        })
     }
 }
 
@@ -127,20 +124,14 @@
         }
     }
 
-    pub fn add_duration(&self, other: &Duration) -> SystemTime {
-        self.checked_add_duration(other).expect("overflow when adding duration to time")
-    }
-
     pub fn checked_add_duration(&self, other: &Duration) -> Option<SystemTime> {
-        checked_dur2intervals(other)
-            .and_then(|d| self.intervals().checked_add(d))
-            .map(|i| SystemTime::from_intervals(i))
+        let intervals = self.intervals().checked_add(checked_dur2intervals(other)?)?;
+        Some(SystemTime::from_intervals(intervals))
     }
 
-    pub fn sub_duration(&self, other: &Duration) -> SystemTime {
-        let intervals = self.intervals().checked_sub(dur2intervals(other))
-                            .expect("overflow when subtracting from time");
-        SystemTime::from_intervals(intervals)
+    pub fn checked_sub_duration(&self, other: &Duration) -> Option<SystemTime> {
+        let intervals = self.intervals().checked_sub(checked_dur2intervals(other)?)?;
+        Some(SystemTime::from_intervals(intervals))
     }
 }
 
@@ -184,16 +175,12 @@
     }
 }
 
-fn checked_dur2intervals(d: &Duration) -> Option<i64> {
-    d.as_secs()
-        .checked_mul(INTERVALS_PER_SEC)
-        .and_then(|i| i.checked_add(d.subsec_nanos() as u64 / 100))
-        .and_then(|i| i.try_into().ok())
-}
-
-fn dur2intervals(d: &Duration) -> i64 {
-    checked_dur2intervals(d)
-        .expect("overflow when converting duration to intervals")
+fn checked_dur2intervals(dur: &Duration) -> Option<i64> {
+    dur.as_secs()
+        .checked_mul(INTERVALS_PER_SEC)?
+        .checked_add(dur.subsec_nanos() as u64 / 100)?
+        .try_into()
+        .ok()
 }
 
 fn intervals2dur(intervals: u64) -> Duration {
diff --git a/src/libstd/sys_common/condvar.rs b/src/libstd/sys_common/condvar.rs
index 16bf080..b6f29dd 100644
--- a/src/libstd/sys_common/condvar.rs
+++ b/src/libstd/sys_common/condvar.rs
@@ -25,7 +25,6 @@
     ///
     /// Behavior is undefined if the condition variable is moved after it is
     /// first used with any of the functions below.
-    #[unstable(feature = "sys_internals", issue = "0")] // FIXME: min_const_fn
     pub const fn new() -> Condvar { Condvar(imp::Condvar::new()) }
 
     /// Prepares the condition variable for use.
diff --git a/src/libstd/sys_common/mutex.rs b/src/libstd/sys_common/mutex.rs
index 8768423..c6d531c 100644
--- a/src/libstd/sys_common/mutex.rs
+++ b/src/libstd/sys_common/mutex.rs
@@ -27,7 +27,6 @@
     /// Also, until `init` is called, behavior is undefined if this
     /// mutex is ever used reentrantly, i.e., `raw_lock` or `try_lock`
     /// are called by the thread currently holding the lock.
-    #[unstable(feature = "sys_internals", issue = "0")] // FIXME: min_const_fn
     pub const fn new() -> Mutex { Mutex(imp::Mutex::new()) }
 
     /// Prepare the mutex for use.
diff --git a/src/libstd/sys_common/rwlock.rs b/src/libstd/sys_common/rwlock.rs
index a430c25..71a4f01 100644
--- a/src/libstd/sys_common/rwlock.rs
+++ b/src/libstd/sys_common/rwlock.rs
@@ -22,7 +22,6 @@
     ///
     /// Behavior is undefined if the reader-writer lock is moved after it is
     /// first used with any of the functions below.
-    #[unstable(feature = "sys_internals", issue = "0")] // FIXME: min_const_fn
     pub const fn new() -> RWLock { RWLock(imp::RWLock::new()) }
 
     /// Acquires shared access to the underlying lock, blocking the current
diff --git a/src/libstd/time.rs b/src/libstd/time.rs
index 6678104..63cede7 100644
--- a/src/libstd/time.rs
+++ b/src/libstd/time.rs
@@ -208,6 +208,22 @@
     pub fn elapsed(&self) -> Duration {
         Instant::now() - *self
     }
+
+    /// Returns `Some(t)` where `t` is the time `self + duration` if `t` can be represented as
+    /// `Instant` (which means it's inside the bounds of the underlying data structure), `None`
+    /// otherwise.
+    #[unstable(feature = "time_checked_add", issue = "55940")]
+    pub fn checked_add(&self, duration: Duration) -> Option<Instant> {
+        self.0.checked_add_duration(&duration).map(|t| Instant(t))
+    }
+
+    /// Returns `Some(t)` where `t` is the time `self - duration` if `t` can be represented as
+    /// `Instant` (which means it's inside the bounds of the underlying data structure), `None`
+    /// otherwise.
+    #[unstable(feature = "time_checked_add", issue = "55940")]
+    pub fn checked_sub(&self, duration: Duration) -> Option<Instant> {
+        self.0.checked_sub_duration(&duration).map(|t| Instant(t))
+    }
 }
 
 #[stable(feature = "time2", since = "1.8.0")]
@@ -215,7 +231,8 @@
     type Output = Instant;
 
     fn add(self, other: Duration) -> Instant {
-        Instant(self.0.add_duration(&other))
+        self.checked_add(other)
+            .expect("overflow when adding duration to instant")
     }
 }
 
@@ -231,7 +248,8 @@
     type Output = Instant;
 
     fn sub(self, other: Duration) -> Instant {
-        Instant(self.0.sub_duration(&other))
+        self.checked_sub(other)
+            .expect("overflow when subtracting duration from instant")
     }
 }
 
@@ -365,6 +383,14 @@
     pub fn checked_add(&self, duration: Duration) -> Option<SystemTime> {
         self.0.checked_add_duration(&duration).map(|t| SystemTime(t))
     }
+
+    /// Returns `Some(t)` where `t` is the time `self - duration` if `t` can be represented as
+    /// `SystemTime` (which means it's inside the bounds of the underlying data structure), `None`
+    /// otherwise.
+    #[unstable(feature = "time_checked_add", issue = "55940")]
+    pub fn checked_sub(&self, duration: Duration) -> Option<SystemTime> {
+        self.0.checked_sub_duration(&duration).map(|t| SystemTime(t))
+    }
 }
 
 #[stable(feature = "time2", since = "1.8.0")]
@@ -372,7 +398,8 @@
     type Output = SystemTime;
 
     fn add(self, dur: Duration) -> SystemTime {
-        SystemTime(self.0.add_duration(&dur))
+        self.checked_add(dur)
+            .expect("overflow when adding duration to instant")
     }
 }
 
@@ -388,7 +415,8 @@
     type Output = SystemTime;
 
     fn sub(self, dur: Duration) -> SystemTime {
-        SystemTime(self.0.sub_duration(&dur))
+        self.checked_sub(dur)
+            .expect("overflow when subtracting duration from instant")
     }
 }
 
@@ -521,6 +549,20 @@
 
         let second = Duration::new(1, 0);
         assert_almost_eq!(a - second + second, a);
+        assert_almost_eq!(a.checked_sub(second).unwrap().checked_add(second).unwrap(), a);
+
+        // checked_add_duration will not panic on overflow
+        let mut maybe_t = Some(Instant::now());
+        let max_duration = Duration::from_secs(u64::max_value());
+        // in case `Instant` can store `>= now + max_duration`.
+        for _ in 0..2 {
+            maybe_t = maybe_t.and_then(|t| t.checked_add(max_duration));
+        }
+        assert_eq!(maybe_t, None);
+
+        // checked_add_duration calculates the right time and will work for another year
+        let year = Duration::from_secs(60 * 60 * 24 * 365);
+        assert_eq!(a + year, a.checked_add(year).unwrap());
     }
 
     #[test]
@@ -557,6 +599,7 @@
                            .duration(), second);
 
         assert_almost_eq!(a - second + second, a);
+        assert_almost_eq!(a.checked_sub(second).unwrap().checked_add(second).unwrap(), a);
 
         // A difference of 80 and 800 years cannot fit inside a 32-bit time_t
         if !(cfg!(unix) && ::mem::size_of::<::libc::time_t>() <= 4) {
diff --git a/src/libsyntax/diagnostics/plugin.rs b/src/libsyntax/diagnostics/plugin.rs
index 1229db9..3b88767 100644
--- a/src/libsyntax/diagnostics/plugin.rs
+++ b/src/libsyntax/diagnostics/plugin.rs
@@ -141,6 +141,7 @@
     ])
 }
 
+#[allow(deprecated)]
 pub fn expand_build_diagnostic_array<'cx>(ecx: &'cx mut ExtCtxt,
                                           span: Span,
                                           token_tree: &[TokenTree])
diff --git a/src/libsyntax/parse/mod.rs b/src/libsyntax/parse/mod.rs
index eb71003..10c451e 100644
--- a/src/libsyntax/parse/mod.rs
+++ b/src/libsyntax/parse/mod.rs
@@ -15,7 +15,7 @@
 use early_buffered_lints::{BufferedEarlyLint, BufferedEarlyLintId};
 use source_map::{SourceMap, FilePathMapping};
 use syntax_pos::{Span, SourceFile, FileName, MultiSpan};
-use errors::{Handler, ColorConfig, Diagnostic, DiagnosticBuilder};
+use errors::{FatalError, Level, Handler, ColorConfig, Diagnostic, DiagnosticBuilder};
 use feature_gate::UnstableFeatures;
 use parse::parser::Parser;
 use ptr::P;
@@ -192,6 +192,14 @@
     source_file_to_parser(sess, file_to_source_file(sess, path, None))
 }
 
+/// Create a new parser, returning buffered diagnostics if the file doesn't
+/// exist or from lexing the initial token stream.
+pub fn maybe_new_parser_from_file<'a>(sess: &'a ParseSess, path: &Path)
+    -> Result<Parser<'a>, Vec<Diagnostic>> {
+    let file = try_file_to_source_file(sess, path, None).map_err(|db| vec![db])?;
+    maybe_source_file_to_parser(sess, file)
+}
+
 /// Given a session, a crate config, a path, and a span, add
 /// the file at the given path to the source_map, and return a parser.
 /// On an error, use the given span as the source of the problem.
@@ -237,17 +245,30 @@
 // base abstractions
 
 /// Given a session and a path and an optional span (for error reporting),
+/// add the path to the session's source_map and return the new source_file or
+/// error when a file can't be read.
+fn try_file_to_source_file(sess: &ParseSess, path: &Path, spanopt: Option<Span>)
+                   -> Result<Lrc<SourceFile>, Diagnostic> {
+    sess.source_map().load_file(path)
+    .map_err(|e| {
+        let msg = format!("couldn't read {}: {}", path.display(), e);
+        let mut diag = Diagnostic::new(Level::Fatal, &msg);
+        if let Some(sp) = spanopt {
+            diag.set_span(sp);
+        }
+        diag
+    })
+}
+
+/// Given a session and a path and an optional span (for error reporting),
 /// add the path to the session's source_map and return the new source_file.
 fn file_to_source_file(sess: &ParseSess, path: &Path, spanopt: Option<Span>)
                    -> Lrc<SourceFile> {
-    match sess.source_map().load_file(path) {
+    match try_file_to_source_file(sess, path, spanopt) {
         Ok(source_file) => source_file,
-        Err(e) => {
-            let msg = format!("couldn't read {}: {}", path.display(), e);
-            match spanopt {
-                Some(sp) => sess.span_diagnostic.span_fatal(sp, &msg).raise(),
-                None => sess.span_diagnostic.fatal(&msg).raise()
-            }
+        Err(d) => {
+            DiagnosticBuilder::new_diagnostic(&sess.span_diagnostic, d).emit();
+            FatalError.raise();
         }
     }
 }
diff --git a/src/libsyntax/parse/token.rs b/src/libsyntax/parse/token.rs
index 8e4d3c0..ed74665 100644
--- a/src/libsyntax/parse/token.rs
+++ b/src/libsyntax/parse/token.rs
@@ -207,6 +207,10 @@
     Eof,
 }
 
+// `Token` is used a lot. Make sure it doesn't unintentionally get bigger.
+#[cfg(target_arch = "x86_64")]
+static_assert!(MEM_SIZE_OF_STATEMENT: mem::size_of::<Token>() == 16);
+
 impl Token {
     pub fn interpolated(nt: Nonterminal) -> Token {
         Token::Interpolated(Lrc::new((nt, LazyTokenStream::new())))
diff --git a/src/libsyntax/source_map.rs b/src/libsyntax/source_map.rs
index 4500812..9a34312 100644
--- a/src/libsyntax/source_map.rs
+++ b/src/libsyntax/source_map.rs
@@ -579,7 +579,7 @@
         match self.span_to_prev_source(sp) {
             Err(_) => None,
             Ok(source) => source.split('\n').last().map(|last_line| {
-                last_line.len() - last_line.trim_left().len()
+                last_line.len() - last_line.trim_start().len()
             })
         }
     }
@@ -593,7 +593,7 @@
     /// if no character could be found or if an error occurred while retrieving the code snippet.
     pub fn span_extend_to_prev_char(&self, sp: Span, c: char) -> Span {
         if let Ok(prev_source) = self.span_to_prev_source(sp) {
-            let prev_source = prev_source.rsplit(c).nth(0).unwrap_or("").trim_left();
+            let prev_source = prev_source.rsplit(c).nth(0).unwrap_or("").trim_start();
             if !prev_source.is_empty() && !prev_source.contains('\n') {
                 return sp.with_lo(BytePos(sp.lo().0 - prev_source.len() as u32));
             }
@@ -613,7 +613,7 @@
         for ws in &[" ", "\t", "\n"] {
             let pat = pat.to_owned() + ws;
             if let Ok(prev_source) = self.span_to_prev_source(sp) {
-                let prev_source = prev_source.rsplit(&pat).nth(0).unwrap_or("").trim_left();
+                let prev_source = prev_source.rsplit(&pat).nth(0).unwrap_or("").trim_start();
                 if !prev_source.is_empty() && (!prev_source.contains('\n') || accept_newlines) {
                     return sp.with_lo(BytePos(sp.lo().0 - prev_source.len() as u32));
                 }
@@ -627,7 +627,7 @@
     pub fn span_until_char(&self, sp: Span, c: char) -> Span {
         match self.span_to_snippet(sp) {
             Ok(snippet) => {
-                let snippet = snippet.split(c).nth(0).unwrap_or("").trim_right();
+                let snippet = snippet.split(c).nth(0).unwrap_or("").trim_end();
                 if !snippet.is_empty() && !snippet.contains('\n') {
                     sp.with_hi(BytePos(sp.lo().0 + snippet.len() as u32))
                 } else {
diff --git a/src/libsyntax_pos/lib.rs b/src/libsyntax_pos/lib.rs
index 8b7ffa4..9aafb9f 100644
--- a/src/libsyntax_pos/lib.rs
+++ b/src/libsyntax_pos/lib.rs
@@ -24,10 +24,13 @@
 #![feature(nll)]
 #![feature(non_exhaustive)]
 #![feature(optin_builtin_traits)]
+#![feature(rustc_attrs)]
 #![feature(specialization)]
+#![feature(step_trait)]
 #![cfg_attr(not(stage0), feature(stdsimd))]
 
 extern crate arena;
+#[macro_use]
 extern crate rustc_data_structures;
 
 #[macro_use]
diff --git a/src/libsyntax_pos/symbol.rs b/src/libsyntax_pos/symbol.rs
index 05c5387..b720db8 100644
--- a/src/libsyntax_pos/symbol.rs
+++ b/src/libsyntax_pos/symbol.rs
@@ -14,6 +14,7 @@
 
 use arena::DroplessArena;
 use rustc_data_structures::fx::FxHashMap;
+use rustc_data_structures::indexed_vec::Idx;
 use serialize::{Decodable, Decoder, Encodable, Encoder};
 
 use std::fmt;
@@ -57,7 +58,7 @@
     }
 
     pub fn without_first_quote(self) -> Ident {
-        Ident::new(Symbol::intern(self.as_str().trim_left_matches('\'')), self.span)
+        Ident::new(Symbol::intern(self.as_str().trim_start_matches('\'')), self.span)
     }
 
     /// "Normalize" ident for use in comparisons using "item hygiene".
@@ -143,9 +144,18 @@
     }
 }
 
-/// A symbol is an interned or gensymed string.
+/// A symbol is an interned or gensymed string. The use of newtype_index! means
+/// that Option<Symbol> only takes up 4 bytes, because newtype_index! reserves
+/// the last 256 values for tagging purposes.
+///
+/// Note that Symbol cannot be a newtype_index! directly because it implements
+/// fmt::Debug, Encodable, and Decodable in special ways.
 #[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
-pub struct Symbol(u32);
+pub struct Symbol(SymbolIndex);
+
+newtype_index! {
+    pub struct SymbolIndex { .. }
+}
 
 // The interner is pointed to by a thread local value which is only set on the main thread
 // with parallelization is disabled. So we don't allow `Symbol` to transfer between threads
@@ -156,6 +166,10 @@
 impl !Sync for Symbol { }
 
 impl Symbol {
+    const fn new(n: u32) -> Self {
+        Symbol(SymbolIndex::from_u32_const(n))
+    }
+
     /// Maps a string to its interned representation.
     pub fn intern(string: &str) -> Self {
         with_interner(|interner| interner.intern(string))
@@ -189,7 +203,7 @@
     }
 
     pub fn as_u32(self) -> u32 {
-        self.0
+        self.0.as_u32()
     }
 }
 
@@ -197,7 +211,7 @@
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         let is_gensymed = with_interner(|interner| interner.is_gensymed(*self));
         if is_gensymed {
-            write!(f, "{}({})", self, self.0)
+            write!(f, "{}({:?})", self, self.0)
         } else {
             write!(f, "{}", self)
         }
@@ -229,6 +243,9 @@
 }
 
 // The `&'static str`s in this type actually point into the arena.
+//
+// Note that normal symbols are indexed upward from 0, and gensyms are indexed
+// downward from SymbolIndex::MAX_AS_U32.
 #[derive(Default)]
 pub struct Interner {
     arena: DroplessArena,
@@ -243,7 +260,7 @@
         for &string in init {
             if string == "" {
                 // We can't allocate empty strings in the arena, so handle this here.
-                let name = Symbol(this.strings.len() as u32);
+                let name = Symbol::new(this.strings.len() as u32);
                 this.names.insert("", name);
                 this.strings.push("");
             } else {
@@ -258,7 +275,7 @@
             return name;
         }
 
-        let name = Symbol(self.strings.len() as u32);
+        let name = Symbol::new(self.strings.len() as u32);
 
         // `from_utf8_unchecked` is safe since we just allocated a `&str` which is known to be
         // UTF-8.
@@ -276,10 +293,10 @@
     }
 
     pub fn interned(&self, symbol: Symbol) -> Symbol {
-        if (symbol.0 as usize) < self.strings.len() {
+        if (symbol.0.as_usize()) < self.strings.len() {
             symbol
         } else {
-            self.interned(self.gensyms[(!0 - symbol.0) as usize])
+            self.interned(self.gensyms[(SymbolIndex::MAX_AS_U32 - symbol.0.as_u32()) as usize])
         }
     }
 
@@ -290,17 +307,17 @@
 
     fn gensymed(&mut self, symbol: Symbol) -> Symbol {
         self.gensyms.push(symbol);
-        Symbol(!0 - self.gensyms.len() as u32 + 1)
+        Symbol::new(SymbolIndex::MAX_AS_U32 - self.gensyms.len() as u32 + 1)
     }
 
     fn is_gensymed(&mut self, symbol: Symbol) -> bool {
-        symbol.0 as usize >= self.strings.len()
+        symbol.0.as_usize() >= self.strings.len()
     }
 
     pub fn get(&self, symbol: Symbol) -> &str {
-        match self.strings.get(symbol.0 as usize) {
+        match self.strings.get(symbol.0.as_usize()) {
             Some(string) => string,
-            None => self.get(self.gensyms[(!0 - symbol.0) as usize]),
+            None => self.get(self.gensyms[(SymbolIndex::MAX_AS_U32 - symbol.0.as_u32()) as usize]),
         }
     }
 }
@@ -324,7 +341,7 @@
         $(
             #[allow(non_upper_case_globals)]
             pub const $konst: Keyword = Keyword {
-                ident: Ident::with_empty_ctxt(super::Symbol($index))
+                ident: Ident::with_empty_ctxt(super::Symbol::new($index))
             };
         )*
 
@@ -709,19 +726,19 @@
     fn interner_tests() {
         let mut i: Interner = Interner::default();
         // first one is zero:
-        assert_eq!(i.intern("dog"), Symbol(0));
+        assert_eq!(i.intern("dog"), Symbol::new(0));
         // re-use gets the same entry:
-        assert_eq!(i.intern("dog"), Symbol(0));
+        assert_eq!(i.intern("dog"), Symbol::new(0));
         // different string gets a different #:
-        assert_eq!(i.intern("cat"), Symbol(1));
-        assert_eq!(i.intern("cat"), Symbol(1));
+        assert_eq!(i.intern("cat"), Symbol::new(1));
+        assert_eq!(i.intern("cat"), Symbol::new(1));
         // dog is still at zero
-        assert_eq!(i.intern("dog"), Symbol(0));
-        assert_eq!(i.gensym("zebra"), Symbol(4294967295));
-        // gensym of same string gets new number :
-        assert_eq!(i.gensym("zebra"), Symbol(4294967294));
+        assert_eq!(i.intern("dog"), Symbol::new(0));
+        assert_eq!(i.gensym("zebra"), Symbol::new(SymbolIndex::MAX_AS_U32));
+        // gensym of same string gets new number:
+        assert_eq!(i.gensym("zebra"), Symbol::new(SymbolIndex::MAX_AS_U32 - 1));
         // gensym of *existing* string gets new number:
-        assert_eq!(i.gensym("dog"), Symbol(4294967293));
+        assert_eq!(i.gensym("dog"), Symbol::new(SymbolIndex::MAX_AS_U32 - 2));
     }
 
     #[test]
diff --git a/src/libtest/lib.rs b/src/libtest/lib.rs
index bca9888..1c87349 100644
--- a/src/libtest/lib.rs
+++ b/src/libtest/lib.rs
@@ -99,6 +99,10 @@
 
 use formatters::{JsonFormatter, OutputFormatter, PrettyFormatter, TerseFormatter};
 
+/// Whether to execute tests concurrently or not
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+pub enum Concurrent { Yes, No }
+
 // The name of a test. By convention this follows the rules for rust
 // paths; i.e., it should be a series of identifiers separated by double
 // colons. This way if some test runner wants to arrange the tests
@@ -1073,8 +1077,12 @@
 where
     F: FnMut(TestEvent) -> io::Result<()>,
 {
-    use std::collections::HashMap;
+    use std::collections::{self, HashMap};
+    use std::hash::BuildHasherDefault;
     use std::sync::mpsc::RecvTimeoutError;
+    // Use a deterministic hasher
+    type TestMap =
+        HashMap<TestDesc, Instant, BuildHasherDefault<collections::hash_map::DefaultHasher>>;
 
     let tests_len = tests.len();
 
@@ -1113,9 +1121,9 @@
 
     let (tx, rx) = channel::<MonitorMsg>();
 
-    let mut running_tests: HashMap<TestDesc, Instant> = HashMap::new();
+    let mut running_tests: TestMap = HashMap::default();
 
-    fn get_timed_out_tests(running_tests: &mut HashMap<TestDesc, Instant>) -> Vec<TestDesc> {
+    fn get_timed_out_tests(running_tests: &mut TestMap) -> Vec<TestDesc> {
         let now = Instant::now();
         let timed_out = running_tests
             .iter()
@@ -1133,7 +1141,7 @@
         timed_out
     };
 
-    fn calc_timeout(running_tests: &HashMap<TestDesc, Instant>) -> Option<Duration> {
+    fn calc_timeout(running_tests: &TestMap) -> Option<Duration> {
         running_tests.values().min().map(|next_timeout| {
             let now = Instant::now();
             if *next_timeout >= now {
@@ -1148,7 +1156,7 @@
         while !remaining.is_empty() {
             let test = remaining.pop().unwrap();
             callback(TeWait(test.desc.clone()))?;
-            run_test(opts, !opts.run_tests, test, tx.clone());
+            run_test(opts, !opts.run_tests, test, tx.clone(), Concurrent::No);
             let (test, result, stdout) = rx.recv().unwrap();
             callback(TeResult(test, result, stdout))?;
         }
@@ -1159,7 +1167,7 @@
                 let timeout = Instant::now() + Duration::from_secs(TEST_WARN_TIMEOUT_S);
                 running_tests.insert(test.desc.clone(), timeout);
                 callback(TeWait(test.desc.clone()))?; //here no pad
-                run_test(opts, !opts.run_tests, test, tx.clone());
+                run_test(opts, !opts.run_tests, test, tx.clone(), Concurrent::Yes);
                 pending += 1;
             }
 
@@ -1191,7 +1199,7 @@
         // All benchmarks run at the end, in serial.
         for b in filtered_benchs {
             callback(TeWait(b.desc.clone()))?;
-            run_test(opts, false, b, tx.clone());
+            run_test(opts, false, b, tx.clone(), Concurrent::No);
             let (test, result, stdout) = rx.recv().unwrap();
             callback(TeResult(test, result, stdout))?;
         }
@@ -1393,6 +1401,7 @@
     force_ignore: bool,
     test: TestDescAndFn,
     monitor_ch: Sender<MonitorMsg>,
+    concurrency: Concurrent,
 ) {
     let TestDescAndFn { desc, testfn } = test;
 
@@ -1409,6 +1418,7 @@
         monitor_ch: Sender<MonitorMsg>,
         nocapture: bool,
         testfn: Box<dyn FnBox() + Send>,
+        concurrency: Concurrent,
     ) {
         // Buffer for capturing standard I/O
         let data = Arc::new(Mutex::new(Vec::new()));
@@ -1443,7 +1453,7 @@
         // the test synchronously, regardless of the concurrency
         // level.
         let supports_threads = !cfg!(target_os = "emscripten") && !cfg!(target_arch = "wasm32");
-        if supports_threads {
+        if concurrency == Concurrent::Yes && supports_threads {
             let cfg = thread::Builder::new().name(name.as_slice().to_owned());
             cfg.spawn(runtest).unwrap();
         } else {
@@ -1464,13 +1474,14 @@
         }
         DynTestFn(f) => {
             let cb = move || __rust_begin_short_backtrace(f);
-            run_test_inner(desc, monitor_ch, opts.nocapture, Box::new(cb))
+            run_test_inner(desc, monitor_ch, opts.nocapture, Box::new(cb), concurrency)
         }
         StaticTestFn(f) => run_test_inner(
             desc,
             monitor_ch,
             opts.nocapture,
             Box::new(move || __rust_begin_short_backtrace(f)),
+            concurrency,
         ),
     }
 }
@@ -1753,6 +1764,7 @@
     use std::sync::mpsc::channel;
     use bench;
     use Bencher;
+    use Concurrent;
 
 
     fn one_ignored_one_unignored_test() -> Vec<TestDescAndFn> {
@@ -1793,7 +1805,7 @@
             testfn: DynTestFn(Box::new(f)),
         };
         let (tx, rx) = channel();
-        run_test(&TestOpts::new(), false, desc, tx);
+        run_test(&TestOpts::new(), false, desc, tx, Concurrent::No);
         let (_, res, _) = rx.recv().unwrap();
         assert!(res != TrOk);
     }
@@ -1811,7 +1823,7 @@
             testfn: DynTestFn(Box::new(f)),
         };
         let (tx, rx) = channel();
-        run_test(&TestOpts::new(), false, desc, tx);
+        run_test(&TestOpts::new(), false, desc, tx, Concurrent::No);
         let (_, res, _) = rx.recv().unwrap();
         assert!(res == TrIgnored);
     }
@@ -1831,7 +1843,7 @@
             testfn: DynTestFn(Box::new(f)),
         };
         let (tx, rx) = channel();
-        run_test(&TestOpts::new(), false, desc, tx);
+        run_test(&TestOpts::new(), false, desc, tx, Concurrent::No);
         let (_, res, _) = rx.recv().unwrap();
         assert!(res == TrOk);
     }
@@ -1851,7 +1863,7 @@
             testfn: DynTestFn(Box::new(f)),
         };
         let (tx, rx) = channel();
-        run_test(&TestOpts::new(), false, desc, tx);
+        run_test(&TestOpts::new(), false, desc, tx, Concurrent::No);
         let (_, res, _) = rx.recv().unwrap();
         assert!(res == TrOk);
     }
@@ -1873,7 +1885,7 @@
             testfn: DynTestFn(Box::new(f)),
         };
         let (tx, rx) = channel();
-        run_test(&TestOpts::new(), false, desc, tx);
+        run_test(&TestOpts::new(), false, desc, tx, Concurrent::No);
         let (_, res, _) = rx.recv().unwrap();
         assert!(res == TrFailedMsg(format!("{} '{}'", failed_msg, expected)));
     }
@@ -1891,7 +1903,7 @@
             testfn: DynTestFn(Box::new(f)),
         };
         let (tx, rx) = channel();
-        run_test(&TestOpts::new(), false, desc, tx);
+        run_test(&TestOpts::new(), false, desc, tx, Concurrent::No);
         let (_, res, _) = rx.recv().unwrap();
         assert!(res == TrFailed);
     }
diff --git a/src/libunwind/Cargo.toml b/src/libunwind/Cargo.toml
index 4760461..2577d6d 100644
--- a/src/libunwind/Cargo.toml
+++ b/src/libunwind/Cargo.toml
@@ -13,5 +13,5 @@
 
 [dependencies]
 core = { path = "../libcore" }
-libc = { path = "../rustc/libc_shim" }
-compiler_builtins = { path = "../rustc/compiler_builtins_shim" }
+libc = { version = "0.2.43", features = ['rustc-dep-of-std'], default-features = false }
+compiler_builtins = "0.1.0"
diff --git a/src/rust-sgx b/src/rust-sgx
deleted file mode 160000
index 9656260..0000000
--- a/src/rust-sgx
+++ /dev/null
@@ -1 +0,0 @@
-Subproject commit 9656260888095f44830641ca7bb3da609a793451
diff --git a/src/rustc/compiler_builtins_shim/Cargo.toml b/src/rustc/compiler_builtins_shim/Cargo.toml
deleted file mode 100644
index 9804177..0000000
--- a/src/rustc/compiler_builtins_shim/Cargo.toml
+++ /dev/null
@@ -1,40 +0,0 @@
-[package]
-name = "compiler_builtins"
-authors = ["The Rust Project Developers"]
-version = "0.0.0"
-build = "../../libcompiler_builtins/build.rs"
-
-[lib]
-path = "../../libcompiler_builtins/src/lib.rs"
-test = false
-doctest = false
-
-[dependencies]
-# Specify the path to libcore; at the time of writing, removing this shim in
-# favor of using compiler-builtins from git results in a compilation failure:
-#
-# Building stage0 std artifacts (x86_64-apple-darwin -> x86_64-apple-darwin)
-#    Compiling compiler_builtins v0.1.0 (https://github.com/rust-lang-nursery/compiler-builtins.git#23f14d3f)
-# error[E0463]: can't find crate for `core`
-#
-# error: aborting due to previous error
-#
-# error: Could not compile `compiler_builtins`.
-#
-# Caused by:
-#   process didn't exit successfully: `/Users/tamird/src/rust/build/bootstrap/debug/rustc --crate-name compiler_builtins /Users/tamird/.cargo/git/checkouts/compiler-builtins-ec094dc45a0179c8/23f14d3/src/lib.rs --error-format json --crate-type lib --emit=dep-info,link -C opt-level=2 --cfg feature="c" --cfg feature="compiler-builtins" --cfg feature="default" --cfg feature="gcc" -C metadata=876d429e8d7eae1f -C extra-filename=-876d429e8d7eae1f --out-dir /Users/tamird/src/rust/build/x86_64-apple-darwin/stage0-std/x86_64-apple-darwin/release/deps --target x86_64-apple-darwin -L dependency=/Users/tamird/src/rust/build/x86_64-apple-darwin/stage0-std/x86_64-apple-darwin/release/deps -L dependency=/Users/tamird/src/rust/build/x86_64-apple-darwin/stage0-std/release/deps --cap-lints allow -L native=/Users/tamird/src/rust/build/x86_64-apple-darwin/stage0-std/x86_64-apple-darwin/release/build/compiler_builtins-f18fab55928102ad/out -l static=compiler-rt` (exit code: 101)
-# thread 'main' panicked at 'command did not execute successfully: "/Users/tamird/src/rust/build/x86_64-apple-darwin/stage0/bin/cargo" "build" "-j" "4" "--target" "x86_64-apple-darwin" "--release" "--features" "panic-unwind jemalloc backtrace" "--manifest-path" "/Users/tamird/src/rust/src/libstd/Cargo.toml" "--message-format" "json"
-# expected success, got: exit code: 101', src/bootstrap/compile.rs:883:8
-#
-# See https://github.com/rust-lang/rfcs/pull/1133.
-core = { path = "../../libcore" }
-
-[build-dependencies]
-cc = "1.0.1"
-
-[features]
-c = []
-default = ["rustbuild", "compiler-builtins"]
-mem = []
-rustbuild = []
-compiler-builtins = []
diff --git a/src/rustc/compiler_builtins_shim/build.rs b/src/rustc/compiler_builtins_shim/build.rs
deleted file mode 100644
index b37543e..0000000
--- a/src/rustc/compiler_builtins_shim/build.rs
+++ /dev/null
@@ -1,15 +0,0 @@
-// Copyright 2015 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 file is left intentionally empty (and not removed) to avoid an issue
-// where this crate is always considered dirty due to compiler-builtins'
-// `cargo:rerun-if-changed=build.rs` directive; since the path is relative, it
-// refers to this file when this shim crate is being built, and the absence of
-// this file is considered by cargo to be equivalent to it having changed.
diff --git a/src/rustc/dlmalloc_shim/Cargo.toml b/src/rustc/dlmalloc_shim/Cargo.toml
deleted file mode 100644
index b6f8550..0000000
--- a/src/rustc/dlmalloc_shim/Cargo.toml
+++ /dev/null
@@ -1,14 +0,0 @@
-[package]
-name = "dlmalloc"
-version = "0.0.0"
-authors = ["The Rust Project Developers"]
-
-[lib]
-path = "../../dlmalloc/src/lib.rs"
-test = false
-bench = false
-doc = false
-
-[dependencies]
-core = { path = "../../libcore" }
-compiler_builtins = { path = "../../rustc/compiler_builtins_shim" }
diff --git a/src/rustc/fortanix-sgx-abi_shim/Cargo.toml b/src/rustc/fortanix-sgx-abi_shim/Cargo.toml
deleted file mode 100644
index fd81d3d..0000000
--- a/src/rustc/fortanix-sgx-abi_shim/Cargo.toml
+++ /dev/null
@@ -1,14 +0,0 @@
-[package]
-name = "fortanix-sgx-abi"
-version = "0.0.0"
-authors = ["The Rust Project Developers"]
-
-[lib]
-path = "../../rust-sgx/fortanix-sgx-abi/src/lib.rs"
-test = false
-bench = false
-doc = false
-
-[dependencies]
-core = { path = "../../libcore" }
-compiler_builtins = { path = "../../rustc/compiler_builtins_shim" }
diff --git a/src/rustc/libc_shim/Cargo.toml b/src/rustc/libc_shim/Cargo.toml
deleted file mode 100644
index ee037ac..0000000
--- a/src/rustc/libc_shim/Cargo.toml
+++ /dev/null
@@ -1,40 +0,0 @@
-[package]
-name = "libc"
-version = "0.0.0"
-authors = ["The Rust Project Developers"]
-
-[lib]
-name = "libc"
-path = "../../liblibc/src/lib.rs"
-test = false
-bench = false
-doc = false
-
-[dependencies]
-# Specify the path to libcore; at the time of writing, removing this shim in
-# favor of using libc from git results in a compilation failure:
-#
-# Building stage0 std artifacts (x86_64-apple-darwin -> x86_64-apple-darwin)
-#    Compiling libc v0.0.0 (file:///Users/tamird/src/rust/src/rustc/libc_shim)
-# error[E0463]: can't find crate for `core`
-#
-# error: aborting due to previous error
-#
-# error: Could not compile `libc`.
-#
-# Caused by:
-#   process didn't exit successfully: `/Users/tamird/src/rust/build/bootstrap/debug/rustc --crate-name libc src/rustc/libc_shim/../../liblibc/src/lib.rs --error-format json --crate-type lib --emit=dep-info,link -C opt-level=2 --cfg feature="default" --cfg feature="no_std" --cfg feature="stdbuild" -C metadata=d758f87058112d7d -C extra-filename=-d758f87058112d7d --out-dir /Users/tamird/src/rust/build/x86_64-apple-darwin/stage0-std/x86_64-apple-darwin/release/deps --target x86_64-apple-darwin -L dependency=/Users/tamird/src/rust/build/x86_64-apple-darwin/stage0-std/x86_64-apple-darwin/release/deps -L dependency=/Users/tamird/src/rust/build/x86_64-apple-darwin/stage0-std/release/deps` (exit code: 101)
-# thread 'main' panicked at 'command did not execute successfully: "/Users/tamird/src/rust/build/x86_64-apple-darwin/stage0/bin/cargo" "build" "-j" "4" "--target" "x86_64-apple-darwin" "--release" "--features" "panic-unwind jemalloc backtrace" "--manifest-path" "/Users/tamird/src/rust/src/libstd/Cargo.toml" "--message-format" "json"
-# expected success, got: exit code: 101', src/bootstrap/compile.rs:883:8
-#
-# See https://github.com/rust-lang/rfcs/pull/1133.
-core = { path = "../../libcore" }
-compiler_builtins = { path = "../compiler_builtins_shim" }
-
-
-[features]
-# Certain parts of libc are conditionally compiled differently than when used
-# outside rustc. See https://github.com/rust-lang/libc/search?l=Rust&q=stdbuild&type=&utf8=%E2%9C%93.
-stdbuild = []
-default = ["stdbuild", "align"]
-align = []
diff --git a/src/stage0.txt b/src/stage0.txt
index 9326e22..843ecae 100644
--- a/src/stage0.txt
+++ b/src/stage0.txt
@@ -12,7 +12,7 @@
 # source tarball for a stable release you'll likely see `1.x.0` for rustc and
 # `0.x.0` for Cargo where they were released on `date`.
 
-date: 2018-10-30
+date: 2018-12-09
 rustc: beta
 cargo: beta
 
diff --git a/src/test/codegen/nounwind-extern.rs b/src/test/codegen/nounwind-extern.rs
new file mode 100644
index 0000000..ed07cf1
--- /dev/null
+++ b/src/test/codegen/nounwind-extern.rs
@@ -0,0 +1,16 @@
+// Copyright 2018 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: -O
+
+#![crate_type = "lib"]
+
+// CHECK: Function Attrs: norecurse nounwind
+pub extern fn foo() {}
diff --git a/src/test/codegen/simd-intrinsic-generic-select.rs b/src/test/codegen/simd-intrinsic-generic-select.rs
index 8a64d74..24a4b2b 100644
--- a/src/test/codegen/simd-intrinsic-generic-select.rs
+++ b/src/test/codegen/simd-intrinsic-generic-select.rs
@@ -21,10 +21,15 @@
 
 #[repr(simd)]
 #[derive(Copy, Clone, PartialEq, Debug)]
+pub struct f32x8(f32, f32, f32, f32, f32, f32, f32, f32);
+
+#[repr(simd)]
+#[derive(Copy, Clone, PartialEq, Debug)]
 pub struct b8x4(pub i8, pub i8, pub i8, pub i8);
 
 extern "platform-intrinsic" {
     fn simd_select<T, U>(x: T, a: U, b: U) -> U;
+    fn simd_select_bitmask<T, U>(x: T, a: U, b: U) -> U;
 }
 
 // CHECK-LABEL: @select
@@ -33,3 +38,10 @@
     // CHECK: select <4 x i1>
     simd_select(m, a, b)
 }
+
+// CHECK-LABEL: @select_bitmask
+#[no_mangle]
+pub unsafe fn select_bitmask(m: i8, a: f32x8, b: f32x8) -> f32x8 {
+    // CHECK: select <8 x i1>
+    simd_select_bitmask(m, a, b)
+}
diff --git a/src/test/compile-fail/issue-10755.rs b/src/test/compile-fail/issue-10755.rs
index 57915bc..bb77748 100644
--- a/src/test/compile-fail/issue-10755.rs
+++ b/src/test/compile-fail/issue-10755.rs
@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// compile-flags: -C linker=llllll -Z linker-flavor=ld
+// compile-flags: -C linker=llllll -C linker-flavor=ld
 // error-pattern: linker `llllll` not found
 
 fn main() {
diff --git a/src/test/compile-fail/nolink-with-link-args.rs b/src/test/compile-fail/nolink-with-link-args.rs
index 6dfd74f..95f827e 100644
--- a/src/test/compile-fail/nolink-with-link-args.rs
+++ b/src/test/compile-fail/nolink-with-link-args.rs
@@ -9,7 +9,7 @@
 // except according to those terms.
 
 // error-pattern:aFdEfSeVEE
-// compile-flags: -Z linker-flavor=ld
+// compile-flags: -C linker-flavor=ld
 
 /* We're testing that link_args are indeed passed when nolink is specified.
 So we try to compile with junk link_args and make sure they are visible in
diff --git a/src/test/debuginfo/function-call.rs b/src/test/debuginfo/function-call.rs
new file mode 100644
index 0000000..266e536
--- /dev/null
+++ b/src/test/debuginfo/function-call.rs
@@ -0,0 +1,52 @@
+// Copyright 2018 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 does not passed with gdb < 8.0. See #53497.
+// min-gdb-version 8.0
+
+// compile-flags:-g
+
+// === GDB TESTS ===================================================================================
+
+// gdb-command:run
+
+// gdb-command:print fun(45, true)
+// gdb-check:$1 = true
+// gdb-command:print fun(444, false)
+// gdb-check:$2 = false
+
+// gdb-command:print r.get_x()
+// gdb-check:$3 = 4
+
+#![allow(dead_code, unused_variables)]
+
+struct RegularStruct {
+    x: i32
+}
+
+impl RegularStruct {
+    fn get_x(&self) -> i32 {
+        self.x
+    }
+}
+
+fn main() {
+    let _ = fun(4, true);
+    let r = RegularStruct{x: 4};
+    let _ = r.get_x();
+
+    zzz(); // #break
+}
+
+fn fun(x: isize, y: bool) -> bool {
+    y
+}
+
+fn zzz() { () }
diff --git a/src/test/debuginfo/pretty-std-collections.rs b/src/test/debuginfo/pretty-std-collections.rs
index a51be37..350b30d 100644
--- a/src/test/debuginfo/pretty-std-collections.rs
+++ b/src/test/debuginfo/pretty-std-collections.rs
@@ -13,7 +13,11 @@
 // ignore-freebsd: gdb package too new
 // ignore-android: FIXME(#10381)
 // compile-flags:-g
-// min-gdb-version 7.7
+
+// The pretty printers being tested here require the patch from
+// https://sourceware.org/bugzilla/show_bug.cgi?id=21763
+// min-gdb-version 8.1
+
 // min-lldb-version: 310
 
 // === GDB TESTS ===================================================================================
diff --git a/src/test/incremental/foreign.rs b/src/test/incremental/foreign.rs
index dbdebef..648e89b 100644
--- a/src/test/incremental/foreign.rs
+++ b/src/test/incremental/foreign.rs
@@ -13,7 +13,7 @@
 
 // revisions: rpass1
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 
diff --git a/src/test/run-make-fulldeps/c-link-to-rust-va-list-fn/checkrust.rs b/src/test/run-make-fulldeps/c-link-to-rust-va-list-fn/checkrust.rs
index 90ad601..0254c7c 100644
--- a/src/test/run-make-fulldeps/c-link-to-rust-va-list-fn/checkrust.rs
+++ b/src/test/run-make-fulldeps/c-link-to-rust-va-list-fn/checkrust.rs
@@ -10,7 +10,7 @@
 
 #![crate_type = "staticlib"]
 #![feature(c_variadic)]
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 
diff --git a/src/test/run-make-fulldeps/issue-25581/test.rs b/src/test/run-make-fulldeps/issue-25581/test.rs
index 6717d16..b084092 100644
--- a/src/test/run-make-fulldeps/issue-25581/test.rs
+++ b/src/test/run-make-fulldeps/issue-25581/test.rs
@@ -8,14 +8,10 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![feature(libc)]
-
-extern crate libc;
-
 #[link(name = "test", kind = "static")]
 extern {
-    fn slice_len(s: &[u8]) -> libc::size_t;
-    fn slice_elem(s: &[u8], idx: libc::size_t) -> u8;
+    fn slice_len(s: &[u8]) -> usize;
+    fn slice_elem(s: &[u8], idx: usize) -> u8;
 }
 
 fn main() {
diff --git a/src/test/run-make-fulldeps/issue-26006/in/time/lib.rs b/src/test/run-make-fulldeps/issue-26006/in/time/lib.rs
index b1d07d5..1427250 100644
--- a/src/test/run-make-fulldeps/issue-26006/in/time/lib.rs
+++ b/src/test/run-make-fulldeps/issue-26006/in/time/lib.rs
@@ -7,7 +7,7 @@
 // <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.
-#![feature(libc)]
+#![feature(rustc_private)]
 extern crate libc;
 
 fn main(){}
diff --git a/src/test/run-make-fulldeps/libtest-json/output.json b/src/test/run-make-fulldeps/libtest-json/output.json
index d8169ec..2b831ea 100644
--- a/src/test/run-make-fulldeps/libtest-json/output.json
+++ b/src/test/run-make-fulldeps/libtest-json/output.json
@@ -2,7 +2,7 @@
 { "type": "test", "event": "started", "name": "a" }
 { "type": "test", "name": "a", "event": "ok" }
 { "type": "test", "event": "started", "name": "b" }
-{ "type": "test", "name": "b", "event": "failed", "stdout": "thread 'b' panicked at 'assertion failed: false', f.rs:18:5\nnote: Run with `RUST_BACKTRACE=1` for a backtrace.\n" }
+{ "type": "test", "name": "b", "event": "failed", "stdout": "thread 'main' panicked at 'assertion failed: false', f.rs:18:5\nnote: Run with `RUST_BACKTRACE=1` environment variable to display a backtrace.\n" }
 { "type": "test", "event": "started", "name": "c" }
 { "type": "test", "name": "c", "event": "ok" }
 { "type": "test", "event": "started", "name": "d" }
diff --git a/src/test/run-make-fulldeps/link-path-order/main.rs b/src/test/run-make-fulldeps/link-path-order/main.rs
index f3502e8..4d38dc8 100644
--- a/src/test/run-make-fulldeps/link-path-order/main.rs
+++ b/src/test/run-make-fulldeps/link-path-order/main.rs
@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 
diff --git a/src/test/run-make-fulldeps/tools.mk b/src/test/run-make-fulldeps/tools.mk
index 3de358f..7939928 100644
--- a/src/test/run-make-fulldeps/tools.mk
+++ b/src/test/run-make-fulldeps/tools.mk
@@ -76,7 +76,7 @@
 # Extra flags needed to compile a working executable with the standard library
 ifdef IS_WINDOWS
 ifdef IS_MSVC
-	EXTRACFLAGS := ws2_32.lib userenv.lib shell32.lib advapi32.lib
+	EXTRACFLAGS := ws2_32.lib userenv.lib advapi32.lib
 else
 	EXTRACFLAGS := -lws2_32 -luserenv
 endif
diff --git a/src/test/run-pass-valgrind/osx-frameworks.rs b/src/test/run-pass-valgrind/osx-frameworks.rs
index 468a20d..afa9374 100644
--- a/src/test/run-pass-valgrind/osx-frameworks.rs
+++ b/src/test/run-pass-valgrind/osx-frameworks.rs
@@ -11,7 +11,7 @@
 // no-prefer-dynamic
 // pretty-expanded FIXME #23616
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 
diff --git a/src/test/run-pass/abort-on-c-abi.rs b/src/test/run-pass/abort-on-c-abi.rs
index 17b2ee3..12b5b78 100644
--- a/src/test/run-pass/abort-on-c-abi.rs
+++ b/src/test/run-pass/abort-on-c-abi.rs
@@ -15,14 +15,11 @@
 // ignore-cloudabi no env and process
 // ignore-emscripten no processes
 
-#![feature(unwind_attributes)]
-
 use std::{env, panic};
 use std::io::prelude::*;
 use std::io;
 use std::process::{Command, Stdio};
 
-#[unwind(aborts)]
 extern "C" fn panic_in_ffi() {
     panic!("Test");
 }
diff --git a/src/test/run-pass/anon-extern-mod.rs b/src/test/run-pass/anon-extern-mod.rs
index 16ca7bc..daa2bd6 100644
--- a/src/test/run-pass/anon-extern-mod.rs
+++ b/src/test/run-pass/anon-extern-mod.rs
@@ -11,7 +11,7 @@
 // pretty-expanded FIXME #23616
 // ignore-wasm32-bare no libc to test ffi with
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 
diff --git a/src/test/run-pass/array-slice-vec/vec-macro-no-std.rs b/src/test/run-pass/array-slice-vec/vec-macro-no-std.rs
index 5091674..7a90a02 100644
--- a/src/test/run-pass/array-slice-vec/vec-macro-no-std.rs
+++ b/src/test/run-pass/array-slice-vec/vec-macro-no-std.rs
@@ -12,7 +12,7 @@
 
 // ignore-emscripten no no_std executables
 
-#![feature(lang_items, start, libc, alloc)]
+#![feature(lang_items, start, rustc_private, alloc)]
 #![no_std]
 
 extern crate std as other;
diff --git a/src/test/run-pass/auxiliary/anon-extern-mod-cross-crate-1.rs b/src/test/run-pass/auxiliary/anon-extern-mod-cross-crate-1.rs
index 741ce35..6b464c5 100644
--- a/src/test/run-pass/auxiliary/anon-extern-mod-cross-crate-1.rs
+++ b/src/test/run-pass/auxiliary/anon-extern-mod-cross-crate-1.rs
@@ -9,7 +9,7 @@
 // except according to those terms.
 
 #![crate_name="anonexternmod"]
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 
diff --git a/src/test/run-pass/auxiliary/check_static_recursion_foreign_helper.rs b/src/test/run-pass/auxiliary/check_static_recursion_foreign_helper.rs
index cd36a8e..4d1acf3 100644
--- a/src/test/run-pass/auxiliary/check_static_recursion_foreign_helper.rs
+++ b/src/test/run-pass/auxiliary/check_static_recursion_foreign_helper.rs
@@ -10,7 +10,7 @@
 
 // Helper definition for test/run-pass/check-static-recursion-foreign.rs.
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 #![crate_name = "check_static_recursion_foreign_helper"]
 #![crate_type = "lib"]
diff --git a/src/test/run-pass/auxiliary/foreign_lib.rs b/src/test/run-pass/auxiliary/foreign_lib.rs
index cef3627..465feb8 100644
--- a/src/test/run-pass/auxiliary/foreign_lib.rs
+++ b/src/test/run-pass/auxiliary/foreign_lib.rs
@@ -10,7 +10,7 @@
 
 #![crate_name="foreign_lib"]
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 pub mod rustrt {
     extern crate libc;
diff --git a/src/test/run-pass/c-stack-as-value.rs b/src/test/run-pass/c-stack-as-value.rs
index df4989d..1f29a52 100644
--- a/src/test/run-pass/c-stack-as-value.rs
+++ b/src/test/run-pass/c-stack-as-value.rs
@@ -11,7 +11,7 @@
 // pretty-expanded FIXME #23616
 // ignore-wasm32-bare no libc to test ffi with
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 mod rustrt {
     extern crate libc;
diff --git a/src/test/run-pass/c-stack-returning-int64.rs b/src/test/run-pass/c-stack-returning-int64.rs
index 56a0437..7dd3b9a 100644
--- a/src/test/run-pass/c-stack-returning-int64.rs
+++ b/src/test/run-pass/c-stack-returning-int64.rs
@@ -10,7 +10,7 @@
 
 // ignore-wasm32-bare no libc to test with
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 
diff --git a/src/test/run-pass/check-static-recursion-foreign.rs b/src/test/run-pass/check-static-recursion-foreign.rs
index a95870c..15f509a 100644
--- a/src/test/run-pass/check-static-recursion-foreign.rs
+++ b/src/test/run-pass/check-static-recursion-foreign.rs
@@ -16,7 +16,7 @@
 
 // pretty-expanded FIXME #23616
 
-#![feature(custom_attribute, libc)]
+#![feature(custom_attribute, rustc_private)]
 
 extern crate check_static_recursion_foreign_helper;
 extern crate libc;
diff --git a/src/test/run-pass/command-before-exec.rs b/src/test/run-pass/command-before-exec.rs
index 5d8bc31..b78fa84 100644
--- a/src/test/run-pass/command-before-exec.rs
+++ b/src/test/run-pass/command-before-exec.rs
@@ -13,7 +13,7 @@
 // ignore-cloudabi no processes
 // ignore-emscripten no processes
 
-#![feature(process_exec, libc)]
+#![feature(process_exec, rustc_private)]
 
 extern crate libc;
 
diff --git a/src/test/run-pass/consts/auxiliary/anon-extern-mod-cross-crate-1.rs b/src/test/run-pass/consts/auxiliary/anon-extern-mod-cross-crate-1.rs
index 741ce35..6b464c5 100644
--- a/src/test/run-pass/consts/auxiliary/anon-extern-mod-cross-crate-1.rs
+++ b/src/test/run-pass/consts/auxiliary/anon-extern-mod-cross-crate-1.rs
@@ -9,7 +9,7 @@
 // except according to those terms.
 
 #![crate_name="anonexternmod"]
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 
diff --git a/src/test/run-pass/core-run-destroy.rs b/src/test/run-pass/core-run-destroy.rs
index 51e26ff..9023326 100644
--- a/src/test/run-pass/core-run-destroy.rs
+++ b/src/test/run-pass/core-run-destroy.rs
@@ -20,7 +20,7 @@
 // memory, which makes for some *confusing* logs. That's why these are here
 // instead of in std.
 
-#![feature(libc, duration)]
+#![feature(rustc_private, duration)]
 
 extern crate libc;
 
diff --git a/src/test/run-pass/cross-crate/auxiliary/anon-extern-mod-cross-crate-1.rs b/src/test/run-pass/cross-crate/auxiliary/anon-extern-mod-cross-crate-1.rs
index 741ce35..6b464c5 100644
--- a/src/test/run-pass/cross-crate/auxiliary/anon-extern-mod-cross-crate-1.rs
+++ b/src/test/run-pass/cross-crate/auxiliary/anon-extern-mod-cross-crate-1.rs
@@ -9,7 +9,7 @@
 // except according to those terms.
 
 #![crate_name="anonexternmod"]
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 
diff --git a/src/test/run-pass/ctfe/references.rs b/src/test/run-pass/ctfe/references.rs
index 946ed24..421f354 100644
--- a/src/test/run-pass/ctfe/references.rs
+++ b/src/test/run-pass/ctfe/references.rs
@@ -28,6 +28,7 @@
         _ => panic!("c"),
     }
 
+    #[allow(unreachable_patterns)]
     match &43 {
         &42 => panic!(),
         BOO => panic!(),
diff --git a/src/test/run-pass/env-funky-keys.rs b/src/test/run-pass/env-funky-keys.rs
index 12e1cbe..7e7899c 100644
--- a/src/test/run-pass/env-funky-keys.rs
+++ b/src/test/run-pass/env-funky-keys.rs
@@ -16,7 +16,7 @@
 // ignore-emscripten no execve
 // no-prefer-dynamic
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 
diff --git a/src/test/run-pass/env-null-vars.rs b/src/test/run-pass/env-null-vars.rs
index 9a46199..cdbecf1 100644
--- a/src/test/run-pass/env-null-vars.rs
+++ b/src/test/run-pass/env-null-vars.rs
@@ -15,7 +15,7 @@
 
 // issue-53200
 
-#![feature(libc)]
+#![feature(rustc_private)]
 extern crate libc;
 
 use std::env;
diff --git a/src/test/run-pass/extern/auxiliary/extern-crosscrate-source.rs b/src/test/run-pass/extern/auxiliary/extern-crosscrate-source.rs
index 150dffe..d20d9db 100644
--- a/src/test/run-pass/extern/auxiliary/extern-crosscrate-source.rs
+++ b/src/test/run-pass/extern/auxiliary/extern-crosscrate-source.rs
@@ -10,7 +10,7 @@
 
 #![crate_name="externcallback"]
 #![crate_type = "lib"]
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 
diff --git a/src/test/run-pass/extern/extern-call-deep.rs b/src/test/run-pass/extern/extern-call-deep.rs
index 6e8d94b..12df0f3 100644
--- a/src/test/run-pass/extern/extern-call-deep.rs
+++ b/src/test/run-pass/extern/extern-call-deep.rs
@@ -10,8 +10,9 @@
 
 // run-pass
 // ignore-wasm32-bare no libc to test ffi with
+// ignore-emscripten blows the JS stack
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 
diff --git a/src/test/run-pass/extern/extern-call-deep2.rs b/src/test/run-pass/extern/extern-call-deep2.rs
index 28157c5..8cb0477 100644
--- a/src/test/run-pass/extern/extern-call-deep2.rs
+++ b/src/test/run-pass/extern/extern-call-deep2.rs
@@ -12,7 +12,7 @@
 #![allow(unused_must_use)]
 // ignore-emscripten no threads support
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 use std::thread;
diff --git a/src/test/run-pass/extern/extern-call-indirect.rs b/src/test/run-pass/extern/extern-call-indirect.rs
index 1badb10..d20721f 100644
--- a/src/test/run-pass/extern/extern-call-indirect.rs
+++ b/src/test/run-pass/extern/extern-call-indirect.rs
@@ -11,7 +11,7 @@
 // run-pass
 // ignore-wasm32-bare no libc to test ffi with
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 
diff --git a/src/test/run-pass/extern/extern-call-scrub.rs b/src/test/run-pass/extern/extern-call-scrub.rs
index ea18069..5e158c2 100644
--- a/src/test/run-pass/extern/extern-call-scrub.rs
+++ b/src/test/run-pass/extern/extern-call-scrub.rs
@@ -16,7 +16,7 @@
 
 // ignore-emscripten no threads support
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 use std::thread;
diff --git a/src/test/run-pass/extern/extern-crosscrate.rs b/src/test/run-pass/extern/extern-crosscrate.rs
index c6fccbe..b99e27a 100644
--- a/src/test/run-pass/extern/extern-crosscrate.rs
+++ b/src/test/run-pass/extern/extern-crosscrate.rs
@@ -12,7 +12,7 @@
 // aux-build:extern-crosscrate-source.rs
 // ignore-wasm32-bare no libc to test ffi with
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate externcallback;
 extern crate libc;
diff --git a/src/test/run-pass/fds-are-cloexec.rs b/src/test/run-pass/fds-are-cloexec.rs
index a5ae0ae..33e64d8 100644
--- a/src/test/run-pass/fds-are-cloexec.rs
+++ b/src/test/run-pass/fds-are-cloexec.rs
@@ -14,7 +14,7 @@
 // ignore-emscripten no processes
 // ignore-haiku
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 
diff --git a/src/test/run-pass/foreign/auxiliary/foreign_lib.rs b/src/test/run-pass/foreign/auxiliary/foreign_lib.rs
index cef3627..465feb8 100644
--- a/src/test/run-pass/foreign/auxiliary/foreign_lib.rs
+++ b/src/test/run-pass/foreign/auxiliary/foreign_lib.rs
@@ -10,7 +10,7 @@
 
 #![crate_name="foreign_lib"]
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 pub mod rustrt {
     extern crate libc;
diff --git a/src/test/run-pass/foreign/foreign-call-no-runtime.rs b/src/test/run-pass/foreign/foreign-call-no-runtime.rs
index 4837f78..e35ec88 100644
--- a/src/test/run-pass/foreign/foreign-call-no-runtime.rs
+++ b/src/test/run-pass/foreign/foreign-call-no-runtime.rs
@@ -11,7 +11,7 @@
 // run-pass
 // ignore-emscripten no threads support
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 
diff --git a/src/test/run-pass/foreign/foreign-fn-linkname.rs b/src/test/run-pass/foreign/foreign-fn-linkname.rs
index 7587660..8fe90b7 100644
--- a/src/test/run-pass/foreign/foreign-fn-linkname.rs
+++ b/src/test/run-pass/foreign/foreign-fn-linkname.rs
@@ -11,7 +11,7 @@
 // run-pass
 // ignore-wasm32-bare no libc to test ffi with
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 use std::ffi::CString;
diff --git a/src/test/run-pass/foreign/foreign-no-abi.rs b/src/test/run-pass/foreign/foreign-no-abi.rs
index 1d35f08..49ddd09 100644
--- a/src/test/run-pass/foreign/foreign-no-abi.rs
+++ b/src/test/run-pass/foreign/foreign-no-abi.rs
@@ -14,7 +14,7 @@
 // ignore-wasm32-bare no libc to test ffi with
 // pretty-expanded FIXME #23616
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 mod rustrt {
     extern crate libc;
diff --git a/src/test/run-pass/foreign/foreign2.rs b/src/test/run-pass/foreign/foreign2.rs
index bd6c8e6..f8942bc 100644
--- a/src/test/run-pass/foreign/foreign2.rs
+++ b/src/test/run-pass/foreign/foreign2.rs
@@ -13,7 +13,7 @@
 // ignore-wasm32-bare no libc to test ffi with
 // pretty-expanded FIXME #23616
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 
diff --git a/src/test/run-pass/invalid_const_promotion.rs b/src/test/run-pass/invalid_const_promotion.rs
index 0f354e1..3b8a265 100644
--- a/src/test/run-pass/invalid_const_promotion.rs
+++ b/src/test/run-pass/invalid_const_promotion.rs
@@ -15,7 +15,7 @@
 // compile-flags: -C debug_assertions=yes
 
 #![stable(feature = "rustc", since = "1.0.0")]
-#![feature(const_fn, libc, staged_api, rustc_attrs)]
+#![feature(const_fn, rustc_private, staged_api, rustc_attrs)]
 #![allow(const_err)]
 
 extern crate libc;
diff --git a/src/test/run-pass/issues/issue-13259-windows-tcb-trash.rs b/src/test/run-pass/issues/issue-13259-windows-tcb-trash.rs
index de18e09..9c983ea 100644
--- a/src/test/run-pass/issues/issue-13259-windows-tcb-trash.rs
+++ b/src/test/run-pass/issues/issue-13259-windows-tcb-trash.rs
@@ -9,7 +9,7 @@
 // except according to those terms.
 
 // run-pass
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 
diff --git a/src/test/run-pass/issues/issue-2214.rs b/src/test/run-pass/issues/issue-2214.rs
index 8329847..f3795c2 100644
--- a/src/test/run-pass/issues/issue-2214.rs
+++ b/src/test/run-pass/issues/issue-2214.rs
@@ -11,7 +11,7 @@
 // run-pass
 // ignore-wasm32-bare no libc to test ffi with
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 
diff --git a/src/test/run-pass/issues/issue-30490.rs b/src/test/run-pass/issues/issue-30490.rs
index 500999c..47f60fb 100644
--- a/src/test/run-pass/issues/issue-30490.rs
+++ b/src/test/run-pass/issues/issue-30490.rs
@@ -18,7 +18,7 @@
 // where the descriptors to inherit were already stdio descriptors.
 // This test checks to avoid that regression.
 
-#![cfg_attr(unix, feature(libc))]
+#![cfg_attr(unix, feature(rustc_private))]
 #![cfg_attr(windows, allow(unused_imports))]
 
 #[cfg(unix)]
diff --git a/src/test/run-pass/issues/issue-3656.rs b/src/test/run-pass/issues/issue-3656.rs
index 63b2740..99a7244 100644
--- a/src/test/run-pass/issues/issue-3656.rs
+++ b/src/test/run-pass/issues/issue-3656.rs
@@ -19,7 +19,7 @@
 // pretty-expanded FIXME #23616
 // ignore-wasm32-bare no libc to test with
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 use libc::{c_uint, uint32_t, c_void};
diff --git a/src/test/run-pass/multi-panic.rs b/src/test/run-pass/multi-panic.rs
index 2e6e109..03e58fc 100644
--- a/src/test/run-pass/multi-panic.rs
+++ b/src/test/run-pass/multi-panic.rs
@@ -17,7 +17,8 @@
     let mut it = err.lines();
 
     assert_eq!(it.next().map(|l| l.starts_with("thread '<unnamed>' panicked at")), Some(true));
-    assert_eq!(it.next(), Some("note: Run with `RUST_BACKTRACE=1` for a backtrace."));
+    assert_eq!(it.next(), Some("note: Run with `RUST_BACKTRACE=1` \
+                                environment variable to display a backtrace."));
     assert_eq!(it.next().map(|l| l.starts_with("thread 'main' panicked at")), Some(true));
     assert_eq!(it.next(), None);
 }
diff --git a/src/test/run-pass/no-stdio.rs b/src/test/run-pass/no-stdio.rs
index d342417..2f5bfbb 100644
--- a/src/test/run-pass/no-stdio.rs
+++ b/src/test/run-pass/no-stdio.rs
@@ -12,7 +12,7 @@
 // ignore-cloudabi no processes
 // ignore-emscripten no processes
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 
diff --git a/src/test/run-pass/out-of-stack.rs b/src/test/run-pass/out-of-stack.rs
index cd0f7cd..1c714e7 100644
--- a/src/test/run-pass/out-of-stack.rs
+++ b/src/test/run-pass/out-of-stack.rs
@@ -16,7 +16,7 @@
 // ignore-emscripten no processes
 
 #![feature(asm)]
-#![feature(libc)]
+#![feature(rustc_private)]
 
 #[cfg(unix)]
 extern crate libc;
diff --git a/src/test/run-pass/rfcs/rfc-1014-2.rs b/src/test/run-pass/rfcs/rfc-1014-2.rs
index 7fbc0d1..257c7f5 100644
--- a/src/test/run-pass/rfcs/rfc-1014-2.rs
+++ b/src/test/run-pass/rfcs/rfc-1014-2.rs
@@ -11,7 +11,7 @@
 // run-pass
 #![allow(dead_code)]
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 
diff --git a/src/test/run-pass/rfcs/rfc-1014.rs b/src/test/run-pass/rfcs/rfc-1014.rs
index d101c3c..578a7f4 100644
--- a/src/test/run-pass/rfcs/rfc-1014.rs
+++ b/src/test/run-pass/rfcs/rfc-1014.rs
@@ -13,7 +13,7 @@
 // ignore-cloudabi stdout does not map to file descriptor 1 by default
 // ignore-wasm32-bare no libc
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 
diff --git a/src/test/run-pass/segfault-no-out-of-stack.rs b/src/test/run-pass/segfault-no-out-of-stack.rs
index a85fe67..961b802 100644
--- a/src/test/run-pass/segfault-no-out-of-stack.rs
+++ b/src/test/run-pass/segfault-no-out-of-stack.rs
@@ -12,7 +12,7 @@
 // ignore-cloudabi can't run commands
 // ignore-emscripten can't run commands
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 
diff --git a/src/test/run-pass/signal-alternate-stack-cleanup.rs b/src/test/run-pass/signal-alternate-stack-cleanup.rs
index ad099f8..a79ab20 100644
--- a/src/test/run-pass/signal-alternate-stack-cleanup.rs
+++ b/src/test/run-pass/signal-alternate-stack-cleanup.rs
@@ -16,7 +16,7 @@
 // ignore-wasm32-bare no libc
 // ignore-windows
 
-#![feature(libc)]
+#![feature(rustc_private)]
 extern crate libc;
 
 use libc::*;
diff --git a/src/test/run-pass/simd/simd-intrinsic-generic-select.rs b/src/test/run-pass/simd/simd-intrinsic-generic-select.rs
index 590a299..74b99ca 100644
--- a/src/test/run-pass/simd/simd-intrinsic-generic-select.rs
+++ b/src/test/run-pass/simd/simd-intrinsic-generic-select.rs
@@ -28,6 +28,10 @@
 
 #[repr(simd)]
 #[derive(Copy, Clone, PartialEq, Debug)]
+struct u32x8(u32, u32, u32, u32, u32, u32, u32, u32);
+
+#[repr(simd)]
+#[derive(Copy, Clone, PartialEq, Debug)]
 struct f32x4(pub f32, pub f32, pub f32, pub f32);
 
 #[repr(simd)]
@@ -36,6 +40,7 @@
 
 extern "platform-intrinsic" {
     fn simd_select<T, U>(x: T, a: U, b: U) -> U;
+    fn simd_select_bitmask<T, U>(x: T, a: U, b: U) -> U;
 }
 
 fn main() {
@@ -146,4 +151,29 @@
         let e = b8x4(t, f, t, t);
         assert_eq!(r, e);
     }
+
+    unsafe {
+        let a = u32x8(0, 1, 2, 3, 4, 5, 6, 7);
+        let b = u32x8(8, 9, 10, 11, 12, 13, 14, 15);
+
+        let r: u32x8 = simd_select_bitmask(0u8, a, b);
+        let e = b;
+        assert_eq!(r, e);
+
+        let r: u32x8 = simd_select_bitmask(0xffu8, a, b);
+        let e = a;
+        assert_eq!(r, e);
+
+        let r: u32x8 = simd_select_bitmask(0b01010101u8, a, b);
+        let e = u32x8(0, 9, 2, 11, 4, 13, 6, 15);
+        assert_eq!(r, e);
+
+        let r: u32x8 = simd_select_bitmask(0b10101010u8, a, b);
+        let e = u32x8(8, 1, 10, 3, 12, 5, 14, 7);
+        assert_eq!(r, e);
+
+        let r: u32x8 = simd_select_bitmask(0b11110000u8, a, b);
+        let e = u32x8(8, 9, 10, 11, 4, 5, 6, 7);
+        assert_eq!(r, e);
+    }
 }
diff --git a/src/test/run-pass/statics/static-mut-foreign.rs b/src/test/run-pass/statics/static-mut-foreign.rs
index d9e43dd..460d66a 100644
--- a/src/test/run-pass/statics/static-mut-foreign.rs
+++ b/src/test/run-pass/statics/static-mut-foreign.rs
@@ -15,7 +15,7 @@
 
 // ignore-wasm32-bare no libc to test ffi with
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 
diff --git a/src/test/run-pass/wait-forked-but-failed-child.rs b/src/test/run-pass/wait-forked-but-failed-child.rs
index dc47108..d822b67 100644
--- a/src/test/run-pass/wait-forked-but-failed-child.rs
+++ b/src/test/run-pass/wait-forked-but-failed-child.rs
@@ -11,7 +11,7 @@
 // ignore-cloudabi no processes
 // ignore-emscripten no processes
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 
diff --git a/src/test/rustdoc-ui/.gitattributes b/src/test/rustdoc-ui/.gitattributes
new file mode 100644
index 0000000..2bcabdf
--- /dev/null
+++ b/src/test/rustdoc-ui/.gitattributes
@@ -0,0 +1 @@
+intra-links-warning-crlf.rs eol=crlf
diff --git a/src/test/rustdoc-ui/failed-doctest-output.stdout b/src/test/rustdoc-ui/failed-doctest-output.stdout
index cd19099..bd6fa1f 100644
--- a/src/test/rustdoc-ui/failed-doctest-output.stdout
+++ b/src/test/rustdoc-ui/failed-doctest-output.stdout
@@ -13,13 +13,13 @@
   | ^^ not found in this scope
 
 thread '$DIR/failed-doctest-output.rs - OtherStruct (line 27)' panicked at 'couldn't compile the test', src/librustdoc/test.rs:326:13
-note: Run with `RUST_BACKTRACE=1` for a backtrace.
+note: Run with `RUST_BACKTRACE=1` environment variable to display a backtrace.
 
 ---- $DIR/failed-doctest-output.rs - SomeStruct (line 21) stdout ----
 thread '$DIR/failed-doctest-output.rs - SomeStruct (line 21)' panicked at 'test executable failed:
 
 thread 'main' panicked at 'oh no', $DIR/failed-doctest-output.rs:3:1
-note: Run with `RUST_BACKTRACE=1` for a backtrace.
+note: Run with `RUST_BACKTRACE=1` environment variable to display a backtrace.
 
 ', src/librustdoc/test.rs:361:17
 
diff --git a/src/test/rustdoc-ui/intra-links-warning-crlf.rs b/src/test/rustdoc-ui/intra-links-warning-crlf.rs
new file mode 100644
index 0000000..20f761f
--- /dev/null
+++ b/src/test/rustdoc-ui/intra-links-warning-crlf.rs
@@ -0,0 +1,23 @@
+// ignore-tidy-cr
+
+// compile-pass
+
+// This file checks the spans of intra-link warnings in a file with CRLF line endings. The
+// .gitattributes file in this directory should enforce it.
+
+/// [error]
+pub struct A;
+
+///
+/// docs [error1]
+
+/// docs [error2]
+///
+pub struct B;
+
+/**
+ * This is a multi-line comment.
+ *
+ * It also has an [error].
+ */
+pub struct C;
diff --git a/src/test/rustdoc-ui/intra-links-warning-crlf.stderr b/src/test/rustdoc-ui/intra-links-warning-crlf.stderr
new file mode 100644
index 0000000..62537f2
--- /dev/null
+++ b/src/test/rustdoc-ui/intra-links-warning-crlf.stderr
@@ -0,0 +1,33 @@
+warning: `[error]` cannot be resolved, ignoring it...
+  --> $DIR/intra-links-warning-crlf.rs:8:6
+   |
+LL | /// [error]
+   |      ^^^^^ cannot be resolved, ignoring
+   |
+   = note: #[warn(intra_doc_link_resolution_failure)] on by default
+   = help: to escape `[` and `]` characters, just add '/' before them like `/[` or `/]`
+
+warning: `[error1]` cannot be resolved, ignoring it...
+  --> $DIR/intra-links-warning-crlf.rs:12:11
+   |
+LL | /// docs [error1]
+   |           ^^^^^^ cannot be resolved, ignoring
+   |
+   = help: to escape `[` and `]` characters, just add '/' before them like `/[` or `/]`
+
+warning: `[error2]` cannot be resolved, ignoring it...
+  --> $DIR/intra-links-warning-crlf.rs:14:11
+   |
+LL | /// docs [error2]
+   |           ^^^^^^ cannot be resolved, ignoring
+   |
+   = help: to escape `[` and `]` characters, just add '/' before them like `/[` or `/]`
+
+warning: `[error]` cannot be resolved, ignoring it...
+  --> $DIR/intra-links-warning-crlf.rs:21:20
+   |
+LL |  * It also has an [error].
+   |                    ^^^^^ cannot be resolved, ignoring
+   |
+   = help: to escape `[` and `]` characters, just add '/' before them like `/[` or `/]`
+
diff --git a/src/test/rustdoc-ui/intra-links-warning.rs b/src/test/rustdoc-ui/intra-links-warning.rs
index d6bc275..db2fd32 100644
--- a/src/test/rustdoc-ui/intra-links-warning.rs
+++ b/src/test/rustdoc-ui/intra-links-warning.rs
@@ -55,3 +55,33 @@
     }
 }
 f!("Foo\nbar [BarF] bar\nbaz");
+
+/** # for example,
+ *
+ * time to introduce a link [error]*/
+pub struct A;
+
+/**
+ * # for example,
+ *
+ * time to introduce a link [error]
+ */
+pub struct B;
+
+#[doc = "single line [error]"]
+pub struct C;
+
+#[doc = "single line with \"escaping\" [error]"]
+pub struct D;
+
+/// Item docs.
+#[doc="Hello there!"]
+/// [error]
+pub struct E;
+
+///
+/// docs [error1]
+
+/// docs [error2]
+///
+pub struct F;
diff --git a/src/test/rustdoc-ui/intra-links-warning.stderr b/src/test/rustdoc-ui/intra-links-warning.stderr
index c05f99f..ed31421 100644
--- a/src/test/rustdoc-ui/intra-links-warning.stderr
+++ b/src/test/rustdoc-ui/intra-links-warning.stderr
@@ -55,6 +55,76 @@
    |
    = help: to escape `[` and `]` characters, just add '/' before them like `/[` or `/]`
 
+warning: `[error]` cannot be resolved, ignoring it...
+  --> $DIR/intra-links-warning.rs:61:30
+   |
+LL |  * time to introduce a link [error]*/
+   |                              ^^^^^ cannot be resolved, ignoring
+   |
+   = help: to escape `[` and `]` characters, just add '/' before them like `/[` or `/]`
+
+warning: `[error]` cannot be resolved, ignoring it...
+  --> $DIR/intra-links-warning.rs:67:30
+   |
+LL |  * time to introduce a link [error]
+   |                              ^^^^^ cannot be resolved, ignoring
+   |
+   = help: to escape `[` and `]` characters, just add '/' before them like `/[` or `/]`
+
+warning: `[error]` cannot be resolved, ignoring it...
+  --> $DIR/intra-links-warning.rs:71:1
+   |
+LL | #[doc = "single line [error]"]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: the link appears in this line:
+           
+           single line [error]
+                        ^^^^^
+   = help: to escape `[` and `]` characters, just add '/' before them like `/[` or `/]`
+
+warning: `[error]` cannot be resolved, ignoring it...
+  --> $DIR/intra-links-warning.rs:74:1
+   |
+LL | #[doc = "single line with /"escaping/" [error]"]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: the link appears in this line:
+           
+           single line with "escaping" [error]
+                                        ^^^^^
+   = help: to escape `[` and `]` characters, just add '/' before them like `/[` or `/]`
+
+warning: `[error]` cannot be resolved, ignoring it...
+  --> $DIR/intra-links-warning.rs:77:1
+   |
+LL | / /// Item docs.
+LL | | #[doc="Hello there!"]
+LL | | /// [error]
+   | |___________^
+   |
+   = note: the link appears in this line:
+           
+            [error]
+             ^^^^^
+   = help: to escape `[` and `]` characters, just add '/' before them like `/[` or `/]`
+
+warning: `[error1]` cannot be resolved, ignoring it...
+  --> $DIR/intra-links-warning.rs:83:11
+   |
+LL | /// docs [error1]
+   |           ^^^^^^ cannot be resolved, ignoring
+   |
+   = help: to escape `[` and `]` characters, just add '/' before them like `/[` or `/]`
+
+warning: `[error2]` cannot be resolved, ignoring it...
+  --> $DIR/intra-links-warning.rs:85:11
+   |
+LL | /// docs [error2]
+   |           ^^^^^^ cannot be resolved, ignoring
+   |
+   = help: to escape `[` and `]` characters, just add '/' before them like `/[` or `/]`
+
 warning: `[BarA]` cannot be resolved, ignoring it...
   --> $DIR/intra-links-warning.rs:24:10
    |
@@ -64,37 +134,19 @@
    = help: to escape `[` and `]` characters, just add '/' before them like `/[` or `/]`
 
 warning: `[BarB]` cannot be resolved, ignoring it...
-  --> $DIR/intra-links-warning.rs:28:1
+  --> $DIR/intra-links-warning.rs:30:9
    |
-LL | / /**
-LL | |  * Foo
-LL | |  * bar [BarB] bar
-LL | |  * baz
-LL | |  */
-   | |___^
+LL |  * bar [BarB] bar
+   |         ^^^^ cannot be resolved, ignoring
    |
-   = note: the link appears in this line:
-           
-            bar [BarB] bar
-                 ^^^^
    = help: to escape `[` and `]` characters, just add '/' before them like `/[` or `/]`
 
 warning: `[BarC]` cannot be resolved, ignoring it...
-  --> $DIR/intra-links-warning.rs:35:1
+  --> $DIR/intra-links-warning.rs:37:6
    |
-LL | / /** Foo
-LL | |
-LL | | bar [BarC] bar
-LL | | baz
-...  |
-LL | |
-LL | | */
-   | |__^
+LL | bar [BarC] bar
+   |      ^^^^ cannot be resolved, ignoring
    |
-   = note: the link appears in this line:
-           
-           bar [BarC] bar
-                ^^^^
    = help: to escape `[` and `]` characters, just add '/' before them like `/[` or `/]`
 
 warning: `[BarD]` cannot be resolved, ignoring it...
diff --git a/src/test/rustdoc/proc-macro.rs b/src/test/rustdoc/proc-macro.rs
index 23d0d00..05d64f8 100644
--- a/src/test/rustdoc/proc-macro.rs
+++ b/src/test/rustdoc/proc-macro.rs
@@ -61,3 +61,16 @@
 pub fn some_derive(_item: TokenStream) -> TokenStream {
     TokenStream::new()
 }
+
+// @has some_macros/foo/index.html
+pub mod foo {
+    // @has - '//code' 'pub use some_proc_macro;'
+    // @has - '//a/@href' '../../some_macros/macro.some_proc_macro.html'
+    pub use some_proc_macro;
+    // @has - '//code' 'pub use some_proc_attr;'
+    // @has - '//a/@href' '../../some_macros/attr.some_proc_attr.html'
+    pub use some_proc_attr;
+    // @has - '//code' 'pub use some_derive;'
+    // @has - '//a/@href' '../../some_macros/derive.SomeDerive.html'
+    pub use some_derive;
+}
diff --git a/src/test/ui/error-codes/E0259.rs b/src/test/ui/error-codes/E0259.rs
index 5a47541..b3e633a 100644
--- a/src/test/ui/error-codes/E0259.rs
+++ b/src/test/ui/error-codes/E0259.rs
@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![feature(alloc, libc)]
+#![feature(alloc, rustc_private)]
 #![allow(unused_extern_crates)]
 
 extern crate alloc;
diff --git a/src/test/ui/error-codes/E0424.rs b/src/test/ui/error-codes/E0424.rs
index 445d0c5..20d42da 100644
--- a/src/test/ui/error-codes/E0424.rs
+++ b/src/test/ui/error-codes/E0424.rs
@@ -19,4 +19,5 @@
 }
 
 fn main () {
+    let self = "self"; //~ ERROR E0424
 }
diff --git a/src/test/ui/error-codes/E0424.stderr b/src/test/ui/error-codes/E0424.stderr
index a1b7a5f..5eccd7d 100644
--- a/src/test/ui/error-codes/E0424.stderr
+++ b/src/test/ui/error-codes/E0424.stderr
@@ -4,6 +4,12 @@
 LL |         self.bar(); //~ ERROR E0424
    |         ^^^^ `self` value is a keyword only available in methods with `self` parameter
 
-error: aborting due to previous error
+error[E0424]: expected unit struct/variant or constant, found module `self`
+  --> $DIR/E0424.rs:22:9
+   |
+LL |     let self = "self"; //~ ERROR E0424
+   |         ^^^^ `self` value is a keyword and may not be bound to variables or shadowed
+
+error: aborting due to 2 previous errors
 
 For more information about this error, try `rustc --explain E0424`.
diff --git a/src/test/ui/extern/extern-const.fixed b/src/test/ui/extern/extern-const.fixed
index dca5698..fb17934 100644
--- a/src/test/ui/extern/extern-const.fixed
+++ b/src/test/ui/extern/extern-const.fixed
@@ -7,7 +7,7 @@
 // run-rustfix
 // ignore-wasm32 no external library to link to.
 // compile-flags: -g -Z continue-parse-after-error
-#![feature(libc)]
+#![feature(rustc_private)]
 extern crate libc;
 
 #[link(name = "rust_test_helpers", kind = "static")]
diff --git a/src/test/ui/extern/extern-const.rs b/src/test/ui/extern/extern-const.rs
index 07dbe54..f2585f5 100644
--- a/src/test/ui/extern/extern-const.rs
+++ b/src/test/ui/extern/extern-const.rs
@@ -7,7 +7,7 @@
 // run-rustfix
 // ignore-wasm32 no external library to link to.
 // compile-flags: -g -Z continue-parse-after-error
-#![feature(libc)]
+#![feature(rustc_private)]
 extern crate libc;
 
 #[link(name = "rust_test_helpers", kind = "static")]
diff --git a/src/test/ui/feature-gates/feature-gate-linker-flavor.rs b/src/test/ui/feature-gates/feature-gate-linker-flavor.rs
deleted file mode 100644
index 56ede01..0000000
--- a/src/test/ui/feature-gates/feature-gate-linker-flavor.rs
+++ /dev/null
@@ -1,20 +0,0 @@
-// Copyright 2018 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 is a fake compile fail test as there's no way to generate a
-// `#![feature(linker_flavor)]` error. The only reason we have a `linker_flavor`
-// feature gate is to be able to document `-Z linker-flavor` in the unstable
-// book
-
-#[used]
-//~^ ERROR attribute must be applied to a `static` variable
-fn foo() {}
-
-fn main() {}
diff --git a/src/test/ui/feature-gates/feature-gate-linker-flavor.stderr b/src/test/ui/feature-gates/feature-gate-linker-flavor.stderr
deleted file mode 100644
index 7019a66..0000000
--- a/src/test/ui/feature-gates/feature-gate-linker-flavor.stderr
+++ /dev/null
@@ -1,8 +0,0 @@
-error: attribute must be applied to a `static` variable
-  --> $DIR/feature-gate-linker-flavor.rs:16:1
-   |
-LL | #[used]
-   | ^^^^^^^
-
-error: aborting due to previous error
-
diff --git a/src/test/ui/issues/issue-1251.rs b/src/test/ui/issues/issue-1251.rs
index b42404c..125f6e1 100644
--- a/src/test/ui/issues/issue-1251.rs
+++ b/src/test/ui/issues/issue-1251.rs
@@ -14,7 +14,7 @@
 // pretty-expanded FIXME #23616
 // ignore-wasm32-bare no libc to test ffi with
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 #![crate_id="rust_get_test_int"]
 
diff --git a/src/test/ui/issues/issue-22034.rs b/src/test/ui/issues/issue-22034.rs
index 2708de2..bee324f 100644
--- a/src/test/ui/issues/issue-22034.rs
+++ b/src/test/ui/issues/issue-22034.rs
@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 
diff --git a/src/test/ui/issues/issue-37887.stderr b/src/test/ui/issues/issue-37887.stderr
index 48fb6c2..7a5a5cd 100644
--- a/src/test/ui/issues/issue-37887.stderr
+++ b/src/test/ui/issues/issue-37887.stderr
@@ -4,13 +4,13 @@
 LL |     use libc::*; //~ ERROR unresolved import
    |         ^^^^ maybe a missing `extern crate libc;`?
 
-error[E0658]: use of unstable library feature 'libc': use `libc` from crates.io (see issue #27783)
+error[E0658]: use of unstable library feature 'rustc_private': this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via `Cargo.toml` instead? (see issue #27812)
   --> $DIR/issue-37887.rs:12:5
    |
 LL |     extern crate libc; //~ ERROR use of unstable
    |     ^^^^^^^^^^^^^^^^^^
    |
-   = help: add #![feature(libc)] to the crate attributes to enable
+   = help: add #![feature(rustc_private)] to the crate attributes to enable
 
 error: aborting due to 2 previous errors
 
diff --git a/src/test/ui/lint/lint-ctypes.rs b/src/test/ui/lint/lint-ctypes.rs
index e09aaba..4c9f1f9 100644
--- a/src/test/ui/lint/lint-ctypes.rs
+++ b/src/test/ui/lint/lint-ctypes.rs
@@ -9,7 +9,7 @@
 // except according to those terms.
 
 #![deny(improper_ctypes)]
-#![feature(libc)]
+#![feature(rustc_private)]
 
 #![allow(private_in_public)]
 
diff --git a/src/test/ui/non-copyable-void.rs b/src/test/ui/non-copyable-void.rs
index 63e5f96..3599190 100644
--- a/src/test/ui/non-copyable-void.rs
+++ b/src/test/ui/non-copyable-void.rs
@@ -10,7 +10,7 @@
 
 // ignore-wasm32-bare no libc to test ffi with
 
-#![feature(libc)]
+#![feature(rustc_private)]
 
 extern crate libc;
 
diff --git a/src/test/ui/pattern/const-pat-ice.rs b/src/test/ui/pattern/const-pat-ice.rs
new file mode 100644
index 0000000..6496a2a
--- /dev/null
+++ b/src/test/ui/pattern/const-pat-ice.rs
@@ -0,0 +1,13 @@
+// failure-status: 101
+
+// This is a repro test for an ICE in our pattern handling of constants.
+
+const FOO: &&&u32 = &&&42;
+
+fn main() {
+    match unimplemented!() {
+        &&&42 => {},
+        FOO => {},
+        _ => {},
+    }
+}
diff --git a/src/test/ui/pattern/irrefutable-exhaustive-integer-binding.rs b/src/test/ui/pattern/irrefutable-exhaustive-integer-binding.rs
new file mode 100644
index 0000000..ff06588
--- /dev/null
+++ b/src/test/ui/pattern/irrefutable-exhaustive-integer-binding.rs
@@ -0,0 +1,8 @@
+// run-pass
+
+fn main() {
+    let -2147483648..=2147483647 = 1;
+    let 0..=255 = 0u8;
+    let -128..=127 = 0i8;
+    let '\u{0000}'..='\u{10FFFF}' = 'v';
+}
diff --git a/src/test/ui/pattern/slice-pattern-const-2.rs b/src/test/ui/pattern/slice-pattern-const-2.rs
index 6f9501d..6cfef11 100644
--- a/src/test/ui/pattern/slice-pattern-const-2.rs
+++ b/src/test/ui/pattern/slice-pattern-const-2.rs
@@ -1,4 +1,4 @@
-// compile-pass
+#![deny(unreachable_patterns)]
 
 fn main() {
     let s = &[0x00; 4][..]; //Slice of any value
@@ -6,19 +6,26 @@
     match s {
         MAGIC_TEST => (),
         [0x00, 0x00, 0x00, 0x00] => (),
-        [4, 5, 6, 7] => (), // this should warn
+        [4, 5, 6, 7] => (), //~ ERROR unreachable pattern
         _ => (),
     }
     match s {
         [0x00, 0x00, 0x00, 0x00] => (),
         MAGIC_TEST => (),
-        [4, 5, 6, 7] => (), // this should warn
+        [4, 5, 6, 7] => (), //~ ERROR unreachable pattern
         _ => (),
     }
     match s {
         [0x00, 0x00, 0x00, 0x00] => (),
         [4, 5, 6, 7] => (),
-        MAGIC_TEST => (), // this should warn
+        MAGIC_TEST => (), // FIXME(oli-obk): this should warn, but currently does not
+        _ => (),
+    }
+    const FOO: [u32; 1] = [4];
+    match [99] {
+        [0x00] => (),
+        [4] => (),
+        FOO => (), //~ ERROR unreachable pattern
         _ => (),
     }
 }
diff --git a/src/test/ui/pattern/slice-pattern-const-2.stderr b/src/test/ui/pattern/slice-pattern-const-2.stderr
new file mode 100644
index 0000000..95651cc
--- /dev/null
+++ b/src/test/ui/pattern/slice-pattern-const-2.stderr
@@ -0,0 +1,26 @@
+error: unreachable pattern
+  --> $DIR/slice-pattern-const-2.rs:9:9
+   |
+LL |         [4, 5, 6, 7] => (), //~ ERROR unreachable pattern
+   |         ^^^^^^^^^^^^
+   |
+note: lint level defined here
+  --> $DIR/slice-pattern-const-2.rs:1:9
+   |
+LL | #![deny(unreachable_patterns)]
+   |         ^^^^^^^^^^^^^^^^^^^^
+
+error: unreachable pattern
+  --> $DIR/slice-pattern-const-2.rs:15:9
+   |
+LL |         [4, 5, 6, 7] => (), //~ ERROR unreachable pattern
+   |         ^^^^^^^^^^^^
+
+error: unreachable pattern
+  --> $DIR/slice-pattern-const-2.rs:28:9
+   |
+LL |         FOO => (), //~ ERROR unreachable pattern
+   |         ^^^
+
+error: aborting due to 3 previous errors
+
diff --git a/src/test/ui/pattern/slice-pattern-const-3.rs b/src/test/ui/pattern/slice-pattern-const-3.rs
index e7a30ce..8805c43 100644
--- a/src/test/ui/pattern/slice-pattern-const-3.rs
+++ b/src/test/ui/pattern/slice-pattern-const-3.rs
@@ -1,4 +1,4 @@
-// compile-pass
+#![deny(unreachable_patterns)]
 
 fn main() {
     let s = &["0x00"; 4][..]; //Slice of any value
@@ -6,19 +6,26 @@
     match s {
         MAGIC_TEST => (),
         ["0x00", "0x00", "0x00", "0x00"] => (),
-        ["4", "5", "6", "7"] => (), // this should warn
+        ["4", "5", "6", "7"] => (), // FIXME(oli-obk): this should warn, but currently does not
         _ => (),
     }
     match s {
         ["0x00", "0x00", "0x00", "0x00"] => (),
         MAGIC_TEST => (),
-        ["4", "5", "6", "7"] => (), // this should warn
+        ["4", "5", "6", "7"] => (), // FIXME(oli-obk): this should warn, but currently does not
         _ => (),
     }
     match s {
         ["0x00", "0x00", "0x00", "0x00"] => (),
         ["4", "5", "6", "7"] => (),
-        MAGIC_TEST => (), // this should warn
+        MAGIC_TEST => (), // FIXME(oli-obk): this should warn, but currently does not
+        _ => (),
+    }
+    const FOO: [&str; 1] = ["boo"];
+    match ["baa"] {
+        ["0x00"] => (),
+        ["boo"] => (),
+        FOO => (), //~ ERROR unreachable pattern
         _ => (),
     }
 }
diff --git a/src/test/ui/pattern/slice-pattern-const-3.stderr b/src/test/ui/pattern/slice-pattern-const-3.stderr
new file mode 100644
index 0000000..531bbbc
--- /dev/null
+++ b/src/test/ui/pattern/slice-pattern-const-3.stderr
@@ -0,0 +1,14 @@
+error: unreachable pattern
+  --> $DIR/slice-pattern-const-3.rs:28:9
+   |
+LL |         FOO => (), //~ ERROR unreachable pattern
+   |         ^^^
+   |
+note: lint level defined here
+  --> $DIR/slice-pattern-const-3.rs:1:9
+   |
+LL | #![deny(unreachable_patterns)]
+   |         ^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to previous error
+
diff --git a/src/test/ui/pattern/slice-pattern-const.rs b/src/test/ui/pattern/slice-pattern-const.rs
index d353f6c..f0a0451 100644
--- a/src/test/ui/pattern/slice-pattern-const.rs
+++ b/src/test/ui/pattern/slice-pattern-const.rs
@@ -1,4 +1,4 @@
-//compile-pass
+#![deny(unreachable_patterns)]
 
 fn main() {
     let s = &[0x00; 4][..]; //Slice of any value
@@ -6,19 +6,42 @@
     match s {
         MAGIC_TEST => (),
         [0x00, 0x00, 0x00, 0x00] => (),
-        [84, 69, 83, 84] => (), // this should warn
+        [84, 69, 83, 84] => (), //~ ERROR unreachable pattern
         _ => (),
     }
     match s {
         [0x00, 0x00, 0x00, 0x00] => (),
         MAGIC_TEST => (),
-        [84, 69, 83, 84] => (), // this should warn
+        [84, 69, 83, 84] => (), //~ ERROR unreachable pattern
         _ => (),
     }
     match s {
         [0x00, 0x00, 0x00, 0x00] => (),
         [84, 69, 83, 84] => (),
-        MAGIC_TEST => (), // this should warn
+        MAGIC_TEST => (), //~ ERROR unreachable pattern
         _ => (),
     }
+    const FOO: [u8; 1] = [4];
+    match [99] {
+        [0x00] => (),
+        [4] => (),
+        FOO => (), //~ ERROR unreachable pattern
+        _ => (),
+    }
+    const BAR: &[u8; 1] = &[4];
+    match &[99] {
+        [0x00] => (),
+        [4] => (),
+        BAR => (), //~ ERROR unreachable pattern
+        b"a" => (),
+        _ => (),
+    }
+
+    const BOO: &[u8; 0] = &[];
+    match &[] {
+        [] => (),
+        BOO => (), //~ ERROR unreachable pattern
+        b"" => (), //~ ERROR unreachable pattern
+        _ => (), //~ ERROR unreachable pattern
+    }
 }
diff --git a/src/test/ui/pattern/slice-pattern-const.stderr b/src/test/ui/pattern/slice-pattern-const.stderr
new file mode 100644
index 0000000..412e015
--- /dev/null
+++ b/src/test/ui/pattern/slice-pattern-const.stderr
@@ -0,0 +1,56 @@
+error: unreachable pattern
+  --> $DIR/slice-pattern-const.rs:9:9
+   |
+LL |         [84, 69, 83, 84] => (), //~ ERROR unreachable pattern
+   |         ^^^^^^^^^^^^^^^^
+   |
+note: lint level defined here
+  --> $DIR/slice-pattern-const.rs:1:9
+   |
+LL | #![deny(unreachable_patterns)]
+   |         ^^^^^^^^^^^^^^^^^^^^
+
+error: unreachable pattern
+  --> $DIR/slice-pattern-const.rs:15:9
+   |
+LL |         [84, 69, 83, 84] => (), //~ ERROR unreachable pattern
+   |         ^^^^^^^^^^^^^^^^
+
+error: unreachable pattern
+  --> $DIR/slice-pattern-const.rs:21:9
+   |
+LL |         MAGIC_TEST => (), //~ ERROR unreachable pattern
+   |         ^^^^^^^^^^
+
+error: unreachable pattern
+  --> $DIR/slice-pattern-const.rs:28:9
+   |
+LL |         FOO => (), //~ ERROR unreachable pattern
+   |         ^^^
+
+error: unreachable pattern
+  --> $DIR/slice-pattern-const.rs:35:9
+   |
+LL |         BAR => (), //~ ERROR unreachable pattern
+   |         ^^^
+
+error: unreachable pattern
+  --> $DIR/slice-pattern-const.rs:43:9
+   |
+LL |         BOO => (), //~ ERROR unreachable pattern
+   |         ^^^
+
+error: unreachable pattern
+  --> $DIR/slice-pattern-const.rs:44:9
+   |
+LL |         b"" => (), //~ ERROR unreachable pattern
+   |         ^^^
+
+error: unreachable pattern
+  --> $DIR/slice-pattern-const.rs:45:9
+   |
+LL |         _ => (), //~ ERROR unreachable pattern
+   |         ^
+
+error: aborting due to 8 previous errors
+
diff --git a/src/test/ui/simd-intrinsic/simd-intrinsic-generic-select.rs b/src/test/ui/simd-intrinsic/simd-intrinsic-generic-select.rs
index d74d681..2a2d35e 100644
--- a/src/test/ui/simd-intrinsic/simd-intrinsic-generic-select.rs
+++ b/src/test/ui/simd-intrinsic/simd-intrinsic-generic-select.rs
@@ -33,6 +33,7 @@
 
 extern "platform-intrinsic" {
     fn simd_select<T, U>(x: T, a: U, b: U) -> U;
+    fn simd_select_bitmask<T, U>(x: T, a: U, b: U) -> U;
 }
 
 fn main() {
@@ -52,5 +53,14 @@
 
         simd_select(z, z, z);
         //~^ ERROR mask element type is `f32`, expected `i_`
+
+        simd_select_bitmask(0u8, x, x);
+        //~^ ERROR mask length `8` != other vector length `4`
+
+        simd_select_bitmask(0.0f32, x, x);
+        //~^ ERROR `f32` is not an integral type
+
+        simd_select_bitmask("x", x, x);
+        //~^ ERROR `&str` is not an integral type
     }
 }
diff --git a/src/test/ui/simd-intrinsic/simd-intrinsic-generic-select.stderr b/src/test/ui/simd-intrinsic/simd-intrinsic-generic-select.stderr
index 61e4202..584f3d5 100644
--- a/src/test/ui/simd-intrinsic/simd-intrinsic-generic-select.stderr
+++ b/src/test/ui/simd-intrinsic/simd-intrinsic-generic-select.stderr
@@ -1,21 +1,39 @@
 error[E0511]: invalid monomorphization of `simd_select` intrinsic: mismatched lengths: mask length `8` != other vector length `4`
-  --> $DIR/simd-intrinsic-generic-select.rs:47:9
+  --> $DIR/simd-intrinsic-generic-select.rs:48:9
    |
 LL |         simd_select(m8, x, x);
    |         ^^^^^^^^^^^^^^^^^^^^^
 
 error[E0511]: invalid monomorphization of `simd_select` intrinsic: mask element type is `u32`, expected `i_`
-  --> $DIR/simd-intrinsic-generic-select.rs:50:9
+  --> $DIR/simd-intrinsic-generic-select.rs:51:9
    |
 LL |         simd_select(x, x, x);
    |         ^^^^^^^^^^^^^^^^^^^^
 
 error[E0511]: invalid monomorphization of `simd_select` intrinsic: mask element type is `f32`, expected `i_`
-  --> $DIR/simd-intrinsic-generic-select.rs:53:9
+  --> $DIR/simd-intrinsic-generic-select.rs:54:9
    |
 LL |         simd_select(z, z, z);
    |         ^^^^^^^^^^^^^^^^^^^^
 
-error: aborting due to 3 previous errors
+error[E0511]: invalid monomorphization of `simd_select_bitmask` intrinsic: mismatched lengths: mask length `8` != other vector length `4`
+  --> $DIR/simd-intrinsic-generic-select.rs:57:9
+   |
+LL |         simd_select_bitmask(0u8, x, x);
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error[E0511]: invalid monomorphization of `simd_select_bitmask` intrinsic: `f32` is not an integral type
+  --> $DIR/simd-intrinsic-generic-select.rs:60:9
+   |
+LL |         simd_select_bitmask(0.0f32, x, x);
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error[E0511]: invalid monomorphization of `simd_select_bitmask` intrinsic: `&str` is not an integral type
+  --> $DIR/simd-intrinsic-generic-select.rs:63:9
+   |
+LL |         simd_select_bitmask("x", x, x);
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to 6 previous errors
 
 For more information about this error, try `rustc --explain E0511`.
diff --git a/src/test/ui/unnecessary-extern-crate.rs b/src/test/ui/unnecessary-extern-crate.rs
index 110cfef..4eb3c3d 100644
--- a/src/test/ui/unnecessary-extern-crate.rs
+++ b/src/test/ui/unnecessary-extern-crate.rs
@@ -11,7 +11,7 @@
 // edition:2018
 
 #![deny(unused_extern_crates)]
-#![feature(alloc, test, libc, crate_visibility_modifier)]
+#![feature(alloc, test, rustc_private, crate_visibility_modifier)]
 
 extern crate libc;
 //~^ ERROR unused extern crate
diff --git a/src/tools/build-manifest/src/main.rs b/src/tools/build-manifest/src/main.rs
index 896b380..ea6c711 100644
--- a/src/tools/build-manifest/src/main.rs
+++ b/src/tools/build-manifest/src/main.rs
@@ -621,8 +621,10 @@
         let asc = self.output.join(format!("{}.asc", filename));
         println!("signing: {:?}", path);
         let mut cmd = Command::new("gpg");
-        cmd.arg("--no-tty")
+        cmd.arg("--pinentry-mode=loopback")
+            .arg("--no-tty")
             .arg("--yes")
+            .arg("--batch")
             .arg("--passphrase-fd").arg("0")
             .arg("--personal-digest-preferences").arg("SHA512")
             .arg("--armor")
diff --git a/src/tools/cargo b/src/tools/cargo
index 28fb200..2cf1f5d 160000
--- a/src/tools/cargo
+++ b/src/tools/cargo
@@ -1 +1 @@
-Subproject commit 28fb20034a5bb42ea589664de2617dd1840506d3
+Subproject commit 2cf1f5dda2f7ed84e94c4d32f643e0f1f15352f0
diff --git a/src/tools/clippy b/src/tools/clippy
index a3c77f6..b7a431e 160000
--- a/src/tools/clippy
+++ b/src/tools/clippy
@@ -1 +1 @@
-Subproject commit a3c77f6ad1c1c185e561e9cd7fdec7db569169d1
+Subproject commit b7a431ea1ddb96a396921bf9b5f2f6d8690cd474
diff --git a/src/tools/compiletest/src/main.rs b/src/tools/compiletest/src/main.rs
index 65f6bff..9aefd15 100644
--- a/src/tools/compiletest/src/main.rs
+++ b/src/tools/compiletest/src/main.rs
@@ -511,7 +511,11 @@
     test::TestOpts {
         filter: config.filter.clone(),
         filter_exact: config.filter_exact,
-        run_ignored: config.run_ignored,
+        run_ignored: if config.run_ignored {
+            test::RunIgnored::Yes
+        } else {
+            test::RunIgnored::No
+        },
         format: if config.quiet {
             test::OutputFormat::Terse
         } else {
diff --git a/src/tools/rustc-std-workspace-core/Cargo.toml b/src/tools/rustc-std-workspace-core/Cargo.toml
new file mode 100644
index 0000000..f000d63
--- /dev/null
+++ b/src/tools/rustc-std-workspace-core/Cargo.toml
@@ -0,0 +1,14 @@
+[package]
+name = "rustc-std-workspace-core"
+version = "1.0.0"
+authors = ["Alex Crichton <alex@alexcrichton.com>"]
+license = 'MIT/Apache-2.0'
+description = """
+Hack for the compiler's own build system
+"""
+
+[lib]
+path = "lib.rs"
+
+[dependencies]
+core = { path = "../../libcore" }
diff --git a/src/tools/rustc-std-workspace-core/README.md b/src/tools/rustc-std-workspace-core/README.md
new file mode 100644
index 0000000..9c2b1fa
--- /dev/null
+++ b/src/tools/rustc-std-workspace-core/README.md
@@ -0,0 +1,29 @@
+# The `rustc-std-workspace-core` crate
+
+This crate is a shim and empty crate which simply depends on `libcore` and
+reexports all of its contents. The crate is the crux of empowering the standard
+library to depend on crates from crates.io
+
+Crates on crates.io that the standard library depend on the
+`rustc-std-workspace-core` crate from crates.io. On crates.io, however, this
+crate is empty. We use `[patch]` to override it to this crate in this
+repository. As a result, crates on crates.io will draw a dependency edge to
+`libcore`, the version defined in this repository. That should draw all the
+dependency edges to ensure Cargo builds crates successfully!
+
+Note that crates on crates.io need to depend on this crate with the name `core`
+for everything to work correctly. To do that they can use:
+
+```toml
+core = { version = "1.0.0", optional = true, package = 'rustc-std-workspace-core' }
+```
+
+Through the use of the `package` key the crate is renamed to `core`, meaning
+it'll look like
+
+```
+--extern core=.../librustc_std_workspace_core-XXXXXXX.rlib
+```
+
+when Cargo invokes the compiler, satisfying the implicit `extern crate core`
+directive injected by the compiler.
diff --git a/src/tools/rustc-std-workspace-core/lib.rs b/src/tools/rustc-std-workspace-core/lib.rs
new file mode 100644
index 0000000..e2946fe
--- /dev/null
+++ b/src/tools/rustc-std-workspace-core/lib.rs
@@ -0,0 +1,6 @@
+#![feature(no_core)]
+#![no_core]
+
+extern crate core;
+
+pub use core::*;
diff --git a/src/tools/tidy/src/deps.rs b/src/tools/tidy/src/deps.rs
index e275892..2b5cff6 100644
--- a/src/tools/tidy/src/deps.rs
+++ b/src/tools/tidy/src/deps.rs
@@ -53,6 +53,7 @@
     "bytesize",           // Apache-2.0, cargo
     "im-rc",              // MPL-2.0+, cargo
     "adler32",            // BSD-3-Clause AND Zlib, cargo dep that isn't used
+    "fortanix-sgx-abi",   // MPL-2.0+, libstd but only for sgx target
 ];
 
 /// Which crates to check against the whitelist?
diff --git a/src/tools/tidy/src/lib.rs b/src/tools/tidy/src/lib.rs
index 53db589..614d205 100644
--- a/src/tools/tidy/src/lib.rs
+++ b/src/tools/tidy/src/lib.rs
@@ -56,15 +56,11 @@
 
 fn filter_dirs(path: &Path) -> bool {
     let skip = [
-        "src/dlmalloc",
         "src/llvm",
         "src/llvm-emscripten",
         "src/libbacktrace",
-        "src/libcompiler_builtins",
         "src/librustc_data_structures/owning_ref",
-        "src/compiler-rt",
-        "src/liblibc",
-        "src/rt/hoedown",
+        "src/vendor",
         "src/tools/cargo",
         "src/tools/clang",
         "src/tools/rls",
diff --git a/src/tools/tidy/src/pal.rs b/src/tools/tidy/src/pal.rs
index 822db25..acf7202 100644
--- a/src/tools/tidy/src/pal.rs
+++ b/src/tools/tidy/src/pal.rs
@@ -26,7 +26,6 @@
 //! exceptions:
 //!
 //! - core may not have platform-specific code
-//! - libcompiler_builtins may have platform-specific code
 //! - libpanic_abort may have platform-specific code
 //! - libpanic_unwind may have platform-specific code
 //! - libunwind may have platform-specific code
@@ -50,8 +49,6 @@
 // Paths that may contain platform-specific code
 const EXCEPTION_PATHS: &[&str] = &[
     // std crates
-    "src/libcompiler_builtins",
-    "src/liblibc",
     "src/libpanic_abort",
     "src/libpanic_unwind",
     "src/libunwind",