Auto merge of #66438 - JohnTitor:rollup-qpv3wia, r=JohnTitor

Rollup of 12 pull requests

Successful merges:

 - #65557 (rename Error::iter_chain() and remove Error::iter_sources())
 - #66013 (Avoid hashing the key twice in `get_query()`.)
 - #66306 (Remove cannot mutate statics in initializer of another static error)
 - #66338 (Update mdbook.)
 - #66388 (Do not ICE on recovery from unmet associated type bound obligation)
 - #66390 (Fix ICE when trying to suggest `Type<>` instead of `Type()`)
 - #66391 (Do not ICE in `if` without `else` in `async fn`)
 - #66398 (Remove some stack frames from `.async` calls)
 - #66410 (miri: helper methods for max values of machine's usize/isize)
 - #66418 (Link to tracking issue in HIR const-check error code description)
 - #66419 (Don't warn labels beginning with `_` on unused_labels lint)
 - #66428 (Cleanup unused function)

Failed merges:

r? @ghost

29 files changed, 354 insertions, 384 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 781184af9a9..bb2bd3c314c 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -54,7 +54,7 @@ version = "0.11.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ee49baf6cb617b853aa8d93bf420db2383fab46d314482ca2803b40d5fde979b"
 dependencies = [
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -104,7 +104,7 @@ checksum = "9a7d5b8723950951411ee34d271d99dddcc2035a16ab25310ea2c8cfd4369652"
 dependencies = [
  "libc",
  "termion",
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -213,12 +213,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "build_const"
-version = "0.2.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "39092a32794787acd8525ee150305ff051b0aa6cc2abaf193924f5ab05425f39"
-
-[[package]]
 name = "build_helper"
 version = "0.1.0"
 
@@ -311,7 +305,7 @@ dependencies = [
  "num_cpus",
  "opener",
  "openssl",
- "percent-encoding 2.0.0",
+ "percent-encoding 2.1.0",
  "pretty_env_logger",
  "remove_dir_all",
  "rustc-workspace-hack",
@@ -330,7 +324,7 @@ dependencies = [
  "unicode-width",
  "url 2.1.0",
  "walkdir",
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -482,7 +476,7 @@ dependencies = [
  "itertools 0.8.0",
  "lazy_static 1.3.0",
  "matches",
- "pulldown-cmark 0.6.0",
+ "pulldown-cmark 0.6.1",
  "quine-mc_cluskey",
  "regex-syntax",
  "semver",
@@ -512,6 +506,26 @@ dependencies = [
 ]
 
 [[package]]
+name = "codespan"
+version = "0.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "de67bdcd653002a6dba3eb53850ce3a485547225d81cb6c2bbdbc5a0cba5d15d"
+dependencies = [
+ "unicode-segmentation",
+]
+
+[[package]]
+name = "codespan-reporting"
+version = "0.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "efd1d915d9e2b2ad696b2cd73215a84823ef3f0e3084d90304204415921b62c6"
+dependencies = [
+ "codespan",
+ "termcolor",
+ "unicode-width",
+]
+
+[[package]]
 name = "colored"
 version = "1.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -564,7 +578,7 @@ dependencies = [
  "serde",
  "serde_json",
  "walkdir",
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -585,7 +599,7 @@ dependencies = [
  "serde_derive",
  "serde_json",
  "tempfile",
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -595,6 +609,34 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8ff012e225ce166d4422e0e78419d901719760f62ae2b7969ca6b564d1b54a9e"
 
 [[package]]
+name = "cookie"
+version = "0.12.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "888604f00b3db336d2af898ec3c1d5d0ddf5e6d462220f2ededc33a87ac4bbd5"
+dependencies = [
+ "time",
+ "url 1.7.2",
+]
+
+[[package]]
+name = "cookie_store"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "46750b3f362965f197996c4448e4a0935e791bf7d6631bfce9ee0af3d24c919c"
+dependencies = [
+ "cookie",
+ "failure",
+ "idna 0.1.5",
+ "log",
+ "publicsuffix",
+ "serde",
+ "serde_json",
+ "time",
+ "try_from",
+ "url 1.7.2",
+]
+
+[[package]]
 name = "core"
 version = "0.0.0"
 dependencies = [
@@ -623,7 +665,7 @@ version = "0.29.0"
 dependencies = [
  "curl",
  "failure",
- "percent-encoding 2.0.0",
+ "percent-encoding 2.1.0",
  "serde",
  "serde_derive",
  "serde_json",
@@ -631,15 +673,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "crc"
-version = "1.8.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d663548de7f5cca343f1e0a48d14dcfb0e9eb4e079ec58883b7251539fa10aeb"
-dependencies = [
- "build_const",
-]
-
-[[package]]
 name = "crc32fast"
 version = "1.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -754,7 +787,7 @@ dependencies = [
  "commoncrypto",
  "hex 0.3.2",
  "openssl",
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -769,7 +802,7 @@ dependencies = [
  "openssl-sys",
  "schannel",
  "socket2",
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -785,7 +818,7 @@ dependencies = [
  "openssl-sys",
  "pkg-config",
  "vcpkg",
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -901,7 +934,7 @@ dependencies = [
  "cfg-if",
  "libc",
  "redox_users",
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -922,6 +955,12 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ea57b42383d091c85abcc2706240b94ab2a8fa1fc81c10ff23c4de06e2a90b5e"
 
 [[package]]
+name = "dunce"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d0ad6bf6a88548d1126045c413548df1453d9be094a8ab9fd59bf1fdd338da4f"
+
+[[package]]
 name = "either"
 version = "1.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1050,15 +1089,15 @@ checksum = "86d4de0081402f5e88cdac65c8dcdcc73118c1a7a465e2a05f0da05843a8ea33"
 
 [[package]]
 name = "flate2"
-version = "1.0.6"
+version = "1.0.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2291c165c8e703ee54ef3055ad6188e3d51108e2ded18e9f2476e774fc5ad3d4"
+checksum = "ad3c5233c9a940c8719031b423d7e6c16af66e031cb0420b0896f5245bf181d3"
 dependencies = [
+ "cfg-if",
  "crc32fast",
  "libc",
  "libz-sys",
- "miniz-sys",
- "miniz_oxide_c_api",
+ "miniz_oxide",
 ]
 
 [[package]]
@@ -1107,7 +1146,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9564fc758e15025b46aa6643b1b77d047d1a56a1aea6e01002ac0c7026876213"
 dependencies = [
  "libc",
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -1359,7 +1398,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a3753954f7bd71f0e671afb8b5a992d1724cf43b7f95a563cd4a0bde94659ca8"
 dependencies = [
  "scopeguard 1.0.0",
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -1378,9 +1417,9 @@ dependencies = [
 
 [[package]]
 name = "http"
-version = "0.1.16"
+version = "0.1.19"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fe67e3678f2827030e89cc4b9e7ecd16d52f132c0b940ab5005f88e821500f6a"
+checksum = "d7e06e336150b178206af098a055e3621e8336027e2b4d126bda0bc64824baaf"
 dependencies = [
  "bytes",
  "fnv",
@@ -1539,7 +1578,7 @@ dependencies = [
  "remove_dir_all",
  "tar",
  "walkdir",
- "winapi 0.3.6",
+ "winapi 0.3.8",
  "xz2",
 ]
 
@@ -1704,7 +1743,7 @@ dependencies = [
  "num_cpus",
  "tokio",
  "tokio-codec",
- "unicase 2.5.1",
+ "unicase",
 ]
 
 [[package]]
@@ -1745,19 +1784,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "libflate"
-version = "0.1.25"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "90c6f86f4b0caa347206f916f8b687b51d77c6ef8ff18d52dd007491fd580529"
-dependencies = [
- "adler32",
- "byteorder",
- "crc32fast",
- "rle-decode-fast",
- "take_mut",
-]
-
-[[package]]
 name = "libgit2-sys"
 version = "0.9.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1926,9 +1952,9 @@ checksum = "7ffc5c5338469d4d3ea17d269fa8ea3512ad247247c30bd2df69e68309ed0a08"
 
 [[package]]
 name = "mdbook"
-version = "0.3.3"
+version = "0.3.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9a070268274c566082efb6b2ace7743e43ba91a70d5c6982981e96d3c05ac81c"
+checksum = "031bdd9d4893c983e2f69ebc4b59070feee8276a584c4aabdcb351235ea28016"
 dependencies = [
  "ammonia",
  "chrono",
@@ -1942,7 +1968,7 @@ dependencies = [
  "log",
  "memchr",
  "open",
- "pulldown-cmark 0.5.3",
+ "pulldown-cmark 0.6.1",
  "regex",
  "serde",
  "serde_derive",
@@ -1955,16 +1981,21 @@ dependencies = [
 
 [[package]]
 name = "mdbook-linkcheck"
-version = "0.3.0"
+version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "77d1f0ba4d1e6b86fa18e8853d026d7d76a97eb7eb5eb052ed80901e43b7fc10"
+checksum = "c0a04db564ca37c47771f8455c825dc941ea851ff0deffcf55a04c512406b409"
 dependencies = [
- "env_logger 0.6.2",
+ "codespan",
+ "codespan-reporting",
+ "dunce",
+ "either",
+ "env_logger 0.7.1",
  "failure",
+ "http",
  "log",
  "mdbook",
- "memchr",
- "pulldown-cmark 0.5.3",
+ "percent-encoding 2.1.0",
+ "pulldown-cmark 0.6.1",
  "rayon",
  "regex",
  "reqwest",
@@ -1972,8 +2003,7 @@ dependencies = [
  "serde",
  "serde_derive",
  "serde_json",
- "structopt 0.2.18",
- "url 1.7.2",
+ "structopt",
 ]
 
 [[package]]
@@ -2000,7 +2030,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e2ffa2c986de11a9df78620c01eeaaf27d94d3ff02bf81bfcca953102dd0c6ff"
 dependencies = [
  "libc",
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -2024,19 +2054,17 @@ version = "0.3.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3e27ca21f40a310bd06d9031785f4801710d566c184a6e15bad4f1d9b65f9425"
 dependencies = [
- "unicase 2.5.1",
+ "unicase",
 ]
 
 [[package]]
 name = "mime_guess"
-version = "2.0.0-alpha.6"
+version = "2.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "30de2e4613efcba1ec63d8133f344076952090c122992a903359be5a4f99c3ed"
+checksum = "1a0ed03949aef72dbdf3116a383d7b38b4768e6f960528cd6a6044aa9ed68599"
 dependencies = [
  "mime",
- "phf",
- "phf_codegen",
- "unicase 1.4.2",
+ "unicase",
 ]
 
 [[package]]
@@ -2049,37 +2077,15 @@ dependencies = [
 ]
 
 [[package]]
-name = "miniz-sys"
-version = "0.1.11"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0300eafb20369952951699b68243ab4334f4b10a88f411c221d444b36c40e649"
-dependencies = [
- "cc",
- "libc",
-]
-
-[[package]]
 name = "miniz_oxide"
-version = "0.2.0"
+version = "0.3.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5ad30a47319c16cde58d0314f5d98202a80c9083b5f61178457403dfb14e509c"
+checksum = "6f3f74f726ae935c3f514300cc6773a0c9492abc5e972d42ba0c0ebb88757625"
 dependencies = [
  "adler32",
 ]
 
 [[package]]
-name = "miniz_oxide_c_api"
-version = "0.2.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "28edaef377517fd9fe3e085c37d892ce7acd1fbeab9239c5a36eec352d8a8b7e"
-dependencies = [
- "cc",
- "crc",
- "libc",
- "miniz_oxide",
-]
-
-[[package]]
 name = "mio"
 version = "0.6.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -2107,7 +2113,7 @@ dependencies = [
  "log",
  "mio",
  "miow 0.3.3",
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -2140,7 +2146,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "396aa0f2003d7df8395cb93e09871561ccc3e785f0acb369170e8cc74ddf9226"
 dependencies = [
  "socket2",
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -2190,7 +2196,7 @@ checksum = "42550d9fb7b6684a6d404d9fa7250c2eb2646df731d1c06afc06dcee9e1bcf88"
 dependencies = [
  "cfg-if",
  "libc",
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -2247,7 +2253,7 @@ version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "998c59e83d9474c01127a96e023b7a04bb061dd286bf8bb939d31dc8d31a7448"
 dependencies = [
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -2359,7 +2365,7 @@ dependencies = [
  "tokio",
  "tokio-named-pipes",
  "tokio-uds",
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -2393,7 +2399,7 @@ dependencies = [
  "rand 0.6.1",
  "rustc_version",
  "smallvec 0.6.10",
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -2408,7 +2414,7 @@ dependencies = [
  "redox_syscall",
  "rustc_version",
  "smallvec 0.6.10",
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -2419,9 +2425,9 @@ checksum = "31010dd2e1ac33d5b46a5b413495239882813e0369f8ed8a5e266f173602f831"
 
 [[package]]
 name = "percent-encoding"
-version = "2.0.0"
+version = "2.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ba4f28a6faf4ffea762ba8f4baef48c61a6db348647c73095034041fc79dd954"
+checksum = "d4fd5641d01c8f18a23da7b6fe29298ff4b55afcccdf78973b24cf3175fee32e"
 
 [[package]]
 name = "pest"
@@ -2512,7 +2518,6 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "234f71a15de2288bcb7e3b6515828d22af7ec8598ee6d24c3b526fa0a80b67a0"
 dependencies = [
  "siphasher",
- "unicase 1.4.2",
 ]
 
 [[package]]
@@ -2620,27 +2625,39 @@ dependencies = [
 ]
 
 [[package]]
+name = "publicsuffix"
+version = "1.5.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9bf259a81de2b2eb9850ec990ec78e6a25319715584fd7652b9b26f96fcb1510"
+dependencies = [
+ "error-chain",
+ "idna 0.2.0",
+ "lazy_static 1.3.0",
+ "regex",
+ "url 2.1.0",
+]
+
+[[package]]
 name = "pulldown-cmark"
 version = "0.5.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "77043da1282374688ee212dc44b3f37ff929431de9c9adc3053bd3cee5630357"
 dependencies = [
  "bitflags",
- "getopts",
  "memchr",
- "unicase 2.5.1",
+ "unicase",
 ]
 
 [[package]]
 name = "pulldown-cmark"
-version = "0.6.0"
+version = "0.6.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "85b0ad0d4c1702965ee6bb5b4ff5e71f83850b497d497e9444302987bf9e26a4"
+checksum = "1c205cc82214f3594e2d50686730314f817c67ffa80fe800cf0db78c3c2b9d9e"
 dependencies = [
  "bitflags",
  "getopts",
  "memchr",
- "unicase 2.5.1",
+ "unicase",
 ]
 
 [[package]]
@@ -2712,7 +2729,7 @@ dependencies = [
  "rand_pcg",
  "rand_xorshift 0.1.0",
  "rustc_version",
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -2807,7 +2824,7 @@ dependencies = [
  "libc",
  "rand_core 0.4.0",
  "rdrand",
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -2934,23 +2951,25 @@ version = "0.5.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4a83fa3702a688b9359eccba92d153ac33fd2e8462f9e0e3fdf155239ea7792e"
 dependencies = [
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
 name = "reqwest"
-version = "0.9.11"
+version = "0.9.22"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e542d9f077c126af32536b6aacc75bb7325400eab8cd0743543be5d91660780d"
+checksum = "2c2064233e442ce85c77231ebd67d9eca395207dec2127fe0bbedde4bd29a650"
 dependencies = [
  "base64",
  "bytes",
+ "cookie",
+ "cookie_store",
  "encoding_rs",
+ "flate2",
  "futures",
  "http",
  "hyper",
  "hyper-tls",
- "libflate",
  "log",
  "mime",
  "mime_guess",
@@ -2958,6 +2977,7 @@ dependencies = [
  "serde",
  "serde_json",
  "serde_urlencoded",
+ "time",
  "tokio",
  "tokio-executor",
  "tokio-io",
@@ -2965,15 +2985,10 @@ dependencies = [
  "tokio-timer",
  "url 1.7.2",
  "uuid",
+ "winreg",
 ]
 
 [[package]]
-name = "rle-decode-fast"
-version = "1.0.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cabe4fa914dec5870285fa7f71f602645da47c486e68486d2b4ceb4a343e90ac"
-
-[[package]]
 name = "rls"
 version = "1.40.0"
 dependencies = [
@@ -3100,6 +3115,7 @@ name = "rustbook"
 version = "0.1.0"
 dependencies = [
  "clap",
+ "codespan-reporting",
  "failure",
  "mdbook",
  "mdbook-linkcheck",
@@ -3397,7 +3413,7 @@ dependencies = [
  "smallvec 0.6.10",
  "syn 0.15.35",
  "url 2.1.0",
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -3946,7 +3962,7 @@ dependencies = [
  "rustfmt-config_proc_macro",
  "serde",
  "serde_json",
- "structopt 0.3.1",
+ "structopt",
  "term 0.6.0",
  "toml",
  "unicode-segmentation",
@@ -3976,7 +3992,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0e1a231dc10abf6749cfa5d7767f25888d484201accbd919b66ab5413c502d56"
 dependencies = [
  "lazy_static 1.3.0",
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -4187,7 +4203,7 @@ dependencies = [
  "cfg-if",
  "libc",
  "redox_syscall",
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -4282,34 +4298,12 @@ checksum = "8ea5119cdb4c55b55d432abb513a0429384878c15dde60cc77b1c99de1a95a6a"
 
 [[package]]
 name = "structopt"
-version = "0.2.18"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "16c2cdbf9cc375f15d1b4141bc48aeef444806655cd0e904207edc8d68d86ed7"
-dependencies = [
- "clap",
- "structopt-derive 0.2.18",
-]
-
-[[package]]
-name = "structopt"
 version = "0.3.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2ac9d6e93dd792b217bf89cda5c14566e3043960c6f9da890c2ba5d09d07804c"
 dependencies = [
  "clap",
- "structopt-derive 0.3.1",
-]
-
-[[package]]
-name = "structopt-derive"
-version = "0.2.18"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "53010261a84b37689f9ed7d395165029f9cc7abb9f56bbfe86bee2597ed25107"
-dependencies = [
- "heck",
- "proc-macro2 0.4.30",
- "quote 0.6.12",
- "syn 0.15.35",
+ "structopt-derive",
 ]
 
 [[package]]
@@ -4454,12 +4448,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "take_mut"
-version = "0.2.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f764005d11ee5f36500a149ace24e00e3da98b0158b3e2d53a7495660d3f4d60"
-
-[[package]]
 name = "tar"
 version = "0.4.20"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -4482,7 +4470,7 @@ dependencies = [
  "rand 0.7.0",
  "redox_syscall",
  "remove_dir_all",
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -4512,7 +4500,7 @@ checksum = "0dd90505d5006a4422d3520b30c781d480b3f36768c2fa2187c3e950bc110464"
 dependencies = [
  "byteorder",
  "dirs",
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -4591,13 +4579,13 @@ dependencies = [
 
 [[package]]
 name = "time"
-version = "0.1.40"
+version = "0.1.42"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d825be0eb33fda1a7e68012d51e9c7f451dc1a69391e7fdc197060bb8c56667b"
+checksum = "db8dcfca086c1143c9270ac42a2bbd8a7ee477b78ac8e45b19abfb0cbede4b6f"
 dependencies = [
  "libc",
  "redox_syscall",
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -4713,7 +4701,7 @@ dependencies = [
  "tokio-io",
  "tokio-reactor",
  "tokio-signal",
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -4757,7 +4745,7 @@ dependencies = [
  "tokio-executor",
  "tokio-io",
  "tokio-reactor",
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -4877,6 +4865,15 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e604eb7b43c06650e854be16a2a03155743d3752dd1c943f6829e26b7a36e382"
 
 [[package]]
+name = "try_from"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "283d3b89e1368717881a9d51dad843cc435380d8109c9e47d38780a324698d8b"
+dependencies = [
+ "cfg-if",
+]
+
+[[package]]
 name = "typenum"
 version = "1.10.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -4896,15 +4893,6 @@ checksum = "535c204ee4d8434478593480b8f86ab45ec9aae0e83c568ca81abf0fd0e88f86"
 
 [[package]]
 name = "unicase"
-version = "1.4.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7f4765f83163b74f957c797ad9253caf97f103fb064d3999aea9568d09fc8a33"
-dependencies = [
- "version_check",
-]
-
-[[package]]
-name = "unicase"
 version = "2.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2e2e6bd1e59e56598518beb94fd6db628ded570326f0a98c679a304bd9f00150"
@@ -4929,9 +4917,9 @@ checksum = "6a0180bc61fc5a987082bfa111f4cc95c4caff7f9799f3e46df09163a937aa25"
 
 [[package]]
 name = "unicode-segmentation"
-version = "1.2.1"
+version = "1.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "aa6024fc12ddfd1c6dbc14a80fa2324d4568849869b779f6bd37e5e4c03344d1"
+checksum = "e83e153d1053cbb5a118eeff7fd5be06ed99153f00dbcd8ae310c5fb2b22edc0"
 
 [[package]]
 name = "unicode-width"
@@ -5000,7 +4988,7 @@ checksum = "75b414f6c464c879d7f9babf951f23bc3743fb7313c081b2e6ca719067ea9d61"
 dependencies = [
  "idna 0.2.0",
  "matches",
- "percent-encoding 2.0.0",
+ "percent-encoding 2.1.0",
  "serde",
 ]
 
@@ -5076,7 +5064,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9d9d7ed3431229a144296213105a390676cc49c9b6a72bd19f3176c98e129fa1"
 dependencies = [
  "same-file",
- "winapi 0.3.6",
+ "winapi 0.3.8",
  "winapi-util",
 ]
 
@@ -5110,9 +5098,9 @@ checksum = "167dc9d6949a9b857f3451275e911c3f44255842c1f7a76f33c55103a909087a"
 
 [[package]]
 name = "winapi"
-version = "0.3.6"
+version = "0.3.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "92c1eb33641e276cfa214a0522acad57be5c56b10cb348b3c5117db75f3ac4b0"
+checksum = "8093091eeb260906a183e6ae1abdba2ef5ef2257a21801128899c3fc699229c6"
 dependencies = [
  "winapi-i686-pc-windows-gnu",
  "winapi-x86_64-pc-windows-gnu",
@@ -5136,7 +5124,7 @@ version = "0.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7168bab6e1daee33b4557efd0e95d5ca70a03706d39fa5f3fe7a236f584b03c9"
 dependencies = [
- "winapi 0.3.6",
+ "winapi 0.3.8",
 ]
 
 [[package]]
@@ -5151,11 +5139,20 @@ version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "561ed901ae465d6185fa7864d63fbd5720d0ef718366c9a4dc83cf6170d7e9ba"
 dependencies = [
- "winapi 0.3.6",
+ "winapi 0.3.8",
  "winapi-util",
 ]
 
 [[package]]
+name = "winreg"
+version = "0.6.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b2986deb581c4fe11b621998a5e53361efe6b48a151178d0cd9eeffa4dc6acc9"
+dependencies = [
+ "winapi 0.3.8",
+]
+
+[[package]]
 name = "ws2_32-sys"
 version = "0.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
diff --git a/src/librustc/hir/lowering.rs b/src/librustc/hir/lowering.rs
index 9c09ce99486..dbbb7f926bc 100644
--- a/src/librustc/hir/lowering.rs
+++ b/src/librustc/hir/lowering.rs
@@ -1862,15 +1862,16 @@ impl<'a> LoweringContext<'a> {
                         if let Ok(snippet) = self.sess.source_map().span_to_snippet(data.span) {
                             // Do not suggest going from `Trait()` to `Trait<>`
                             if data.inputs.len() > 0 {
-                                let split = snippet.find('(').unwrap();
-                                let trait_name = &snippet[0..split];
-                                let args = &snippet[split + 1 .. snippet.len() - 1];
-                                err.span_suggestion(
-                                    data.span,
-                                    "use angle brackets instead",
-                                    format!("{}<{}>", trait_name, args),
-                                    Applicability::MaybeIncorrect,
-                                );
+                                if let Some(split) = snippet.find('(') {
+                                    let trait_name = &snippet[0..split];
+                                    let args = &snippet[split + 1 .. snippet.len() - 1];
+                                    err.span_suggestion(
+                                        data.span,
+                                        "use angle brackets instead",
+                                        format!("{}<{}>", trait_name, args),
+                                        Applicability::MaybeIncorrect,
+                                    );
+                                }
                             }
                         };
                         err.emit();
diff --git a/src/librustc/lib.rs b/src/librustc/lib.rs
index 82994f9170f..38877dee711 100644
--- a/src/librustc/lib.rs
+++ b/src/librustc/lib.rs
@@ -59,6 +59,7 @@
 #![feature(log_syntax)]
 #![feature(associated_type_bounds)]
 #![feature(rustc_attrs)]
+#![feature(hash_raw_entry)]
 
 #![recursion_limit="512"]
 
diff --git a/src/librustc/mir/interpret/pointer.rs b/src/librustc/mir/interpret/pointer.rs
index 1bb4d9ea4d6..7c77b2c0711 100644
--- a/src/librustc/mir/interpret/pointer.rs
+++ b/src/librustc/mir/interpret/pointer.rs
@@ -1,4 +1,5 @@
 use std::fmt::{self, Display};
+use std::convert::TryFrom;
 
 use crate::mir;
 use crate::ty::layout::{self, HasDataLayout, Size};
@@ -40,6 +41,18 @@ pub trait PointerArithmetic: layout::HasDataLayout {
         self.data_layout().pointer_size
     }
 
+    #[inline]
+    fn usize_max(&self) -> u64 {
+        let max_usize_plus_1 = 1u128 << self.pointer_size().bits();
+        u64::try_from(max_usize_plus_1-1).unwrap()
+    }
+
+    #[inline]
+    fn isize_max(&self) -> i64 {
+        let max_isize_plus_1 = 1u128 << (self.pointer_size().bits()-1);
+        i64::try_from(max_isize_plus_1-1).unwrap()
+    }
+
     /// Helper function: truncate given value-"overflowed flag" pair to pointer size and
     /// update "overflowed flag" if there was an overflow.
     /// This should be called by all the other methods before returning!
diff --git a/src/librustc/ty/query/plumbing.rs b/src/librustc/ty/query/plumbing.rs
index 214de35b6d0..52a784d3fc0 100644
--- a/src/librustc/ty/query/plumbing.rs
+++ b/src/librustc/ty/query/plumbing.rs
@@ -14,12 +14,13 @@ use errors::Level;
 use errors::Diagnostic;
 use errors::FatalError;
 use errors::Handler;
-use rustc_data_structures::fx::{FxHashMap};
+use rustc_data_structures::fx::{FxHasher, FxHashMap};
 use rustc_data_structures::sync::{Lrc, Lock};
 use rustc_data_structures::sharded::Sharded;
 use rustc_data_structures::thin_vec::ThinVec;
 #[cfg(not(parallel_compiler))]
 use rustc_data_structures::cold_path;
+use std::hash::{Hash, Hasher};
 use std::mem;
 use std::ptr;
 use std::collections::hash_map::Entry;
@@ -82,8 +83,17 @@ impl<'a, 'tcx, Q: QueryDescription<'tcx>> JobOwner<'a, 'tcx, Q> {
     pub(super) fn try_get(tcx: TyCtxt<'tcx>, span: Span, key: &Q::Key) -> TryGetJob<'a, 'tcx, Q> {
         let cache = Q::query_cache(tcx);
         loop {
-            let mut lock = cache.get_shard_by_value(key).lock();
-            if let Some(value) = lock.results.get(key) {
+            // We compute the key's hash once and then use it for both the
+            // shard lookup and the hashmap lookup. This relies on the fact
+            // that both of them use `FxHasher`.
+            let mut state = FxHasher::default();
+            key.hash(&mut state);
+            let key_hash = state.finish();
+
+            let mut lock = cache.get_shard_by_hash(key_hash).lock();
+            if let Some((_, value)) =
+                lock.results.raw_entry().from_key_hashed_nocheck(key_hash, key)
+            {
                 tcx.prof.query_cache_hit(Q::NAME);
                 let result = (value.value.clone(), value.index);
                 #[cfg(debug_assertions)]
diff --git a/src/librustc_data_structures/sharded.rs b/src/librustc_data_structures/sharded.rs
index 2f972eeccdc..a28a5e0f041 100644
--- a/src/librustc_data_structures/sharded.rs
+++ b/src/librustc_data_structures/sharded.rs
@@ -60,6 +60,7 @@ impl<T> Sharded<T> {
         }
     }
 
+    /// The shard is selected by hashing `val` with `FxHasher`.
     #[inline]
     pub fn get_shard_by_value<K: Hash + ?Sized>(&self, val: &K) -> &Lock<T> {
         if SHARDS == 1 {
@@ -69,6 +70,11 @@ impl<T> Sharded<T> {
         }
     }
 
+    /// Get a shard with a pre-computed hash value. If `get_shard_by_value` is
+    /// ever used in combination with `get_shard_by_hash` on a single `Sharded`
+    /// instance, then `hash` must be computed with `FxHasher`. Otherwise,
+    /// `hash` can be computed with any hasher, so long as that hasher is used
+    /// consistently for each `Sharded` instance.
     #[inline]
     pub fn get_shard_by_hash(&self, hash: u64) -> &Lock<T> {
         let hash_len = mem::size_of::<usize>();
diff --git a/src/librustc_error_codes/error_codes/E0744.md b/src/librustc_error_codes/error_codes/E0744.md
index 254223f3565..b299102fd69 100644
--- a/src/librustc_error_codes/error_codes/E0744.md
+++ b/src/librustc_error_codes/error_codes/E0744.md
@@ -15,3 +15,10 @@ const _: i32 = {
     x
 };
 ```
+
+This will be allowed at some point in the future, but the implementation is not
+yet complete. See the tracking issue for [conditionals] or [loops] in a const
+context for the current status.
+
+[conditionals]: https://github.com/rust-lang/rust/issues/49146
+[loops]: https://github.com/rust-lang/rust/issues/52000
diff --git a/src/librustc_mir/transform/check_consts/validation.rs b/src/librustc_mir/transform/check_consts/validation.rs
index 88f16299dc0..74b22d8e143 100644
--- a/src/librustc_mir/transform/check_consts/validation.rs
+++ b/src/librustc_mir/transform/check_consts/validation.rs
@@ -326,17 +326,7 @@ impl Visitor<'tcx> for Validator<'_, 'mir, 'tcx> {
                 let is_thread_local = self.tcx.has_attr(*def_id, sym::thread_local);
                 if is_thread_local {
                     self.check_op(ops::ThreadLocalAccess);
-                } else if self.const_kind() == ConstKind::Static && context.is_mutating_use() {
-                    // this is not strictly necessary as miri will also bail out
-                    // For interior mutability we can't really catch this statically as that
-                    // goes through raw pointers and intermediate temporaries, so miri has
-                    // to catch this anyway
-
-                    self.tcx.sess.span_err(
-                        self.span,
-                        "cannot mutate statics in the initializer of another static",
-                    );
-                } else {
+                } else if self.const_kind() != ConstKind::Static || !context.is_mutating_use() {
                     self.check_op(ops::StaticAccess);
                 }
             }
diff --git a/src/librustc_mir/transform/qualify_consts.rs b/src/librustc_mir/transform/qualify_consts.rs
index 185a499bf48..964efdec2b9 100644
--- a/src/librustc_mir/transform/qualify_consts.rs
+++ b/src/librustc_mir/transform/qualify_consts.rs
@@ -787,19 +787,6 @@ impl<'a, 'tcx> Visitor<'tcx> for Checker<'a, 'tcx> {
 
                 // Only allow statics (not consts) to refer to other statics.
                 if self.mode == Mode::Static || self.mode == Mode::StaticMut {
-                    if self.mode == Mode::Static
-                        && context.is_mutating_use()
-                        && !self.suppress_errors
-                    {
-                        // this is not strictly necessary as miri will also bail out
-                        // For interior mutability we can't really catch this statically as that
-                        // goes through raw pointers and intermediate temporaries, so miri has
-                        // to catch this anyway
-                        self.tcx.sess.span_err(
-                            self.span,
-                            "cannot mutate statics in the initializer of another static",
-                        );
-                    }
                     return;
                 }
                 unleash_miri!(self);
diff --git a/src/librustc_resolve/late.rs b/src/librustc_resolve/late.rs
index 24d6331bbd3..6b068387974 100644
--- a/src/librustc_resolve/late.rs
+++ b/src/librustc_resolve/late.rs
@@ -1767,7 +1767,9 @@ impl<'a, 'b> LateResolutionVisitor<'a, '_> {
 
     fn with_resolved_label(&mut self, label: Option<Label>, id: NodeId, f: impl FnOnce(&mut Self)) {
         if let Some(label) = label {
-            self.diagnostic_metadata.unused_labels.insert(id, label.ident.span);
+            if label.ident.as_str().as_bytes()[1] != b'_' {
+                self.diagnostic_metadata.unused_labels.insert(id, label.ident.span);
+            }
             self.with_label_rib(NormalRibKind, |this| {
                 let ident = label.ident.modern_and_legacy();
                 this.label_ribs.last_mut().unwrap().bindings.insert(ident, id);
diff --git a/src/librustc_typeck/check/generator_interior.rs b/src/librustc_typeck/check/generator_interior.rs
index ff9c945eec4..6e37c0dbbdf 100644
--- a/src/librustc_typeck/check/generator_interior.rs
+++ b/src/librustc_typeck/check/generator_interior.rs
@@ -244,7 +244,13 @@ impl<'a, 'tcx> Visitor<'tcx> for InteriorVisitor<'a, 'tcx> {
         // can be reborrowed without needing to spill to a temporary.
         // If this were not the case, then we could conceivably have
         // to create intermediate temporaries.)
-        let ty = self.fcx.tables.borrow().expr_ty(expr);
-        self.record(ty, scope, Some(expr), expr.span);
+        //
+        // The type table might not have information for this expression
+        // if it is in a malformed scope. (#66387)
+        if let Some(ty) = self.fcx.tables.borrow().expr_ty_opt(expr) {
+            self.record(ty, scope, Some(expr), expr.span);
+        } else {
+            self.fcx.tcx.sess.delay_span_bug(expr.span, "no type for node");
+        }
     }
 }
diff --git a/src/librustc_typeck/check/mod.rs b/src/librustc_typeck/check/mod.rs
index 41c8fc02662..a8418c5f349 100644
--- a/src/librustc_typeck/check/mod.rs
+++ b/src/librustc_typeck/check/mod.rs
@@ -3108,7 +3108,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         fallback_has_occurred: bool,
         mutate_fullfillment_errors: impl Fn(&mut Vec<traits::FulfillmentError<'tcx>>),
     ) {
-        if let Err(mut errors) = self.fulfillment_cx.borrow_mut().select_where_possible(self) {
+        let result = self.fulfillment_cx.borrow_mut().select_where_possible(self);
+        if let Err(mut errors) = result {
             mutate_fullfillment_errors(&mut errors);
             self.report_fulfillment_errors(&errors, self.inh.body_id, fallback_has_occurred);
         }
diff --git a/src/librustdoc/html/static/main.js b/src/librustdoc/html/static/main.js
index 04c0a0f005b..752b93f2ac5 100644
--- a/src/librustdoc/html/static/main.js
+++ b/src/librustdoc/html/static/main.js
@@ -1081,14 +1081,13 @@ function getSearchElement() {
                 val = paths[paths.length - 1];
                 var contains = paths.slice(0, paths.length > 1 ? paths.length - 1 : 1);
 
+                var lev;
+                var lev_distance;
                 for (j = 0; j < nSearchWords; ++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) {
                         lev = checkPath(contains, paths[paths.length - 1], ty);
@@ -1633,7 +1632,7 @@ function getSearchElement() {
             }
 
             var filterCrates = getFilterCrates();
-            showResults(execSearch(query, index, filterCrates), filterCrates);
+            showResults(execSearch(query, index, filterCrates));
         }
 
         function buildIndex(rawSearchIndex) {
diff --git a/src/libstd/error.rs b/src/libstd/error.rs
index 6b9a35fccc4..df24b6635f4 100644
--- a/src/libstd/error.rs
+++ b/src/libstd/error.rs
@@ -725,6 +725,9 @@ impl dyn Error {
     /// Returns an iterator starting with the current error and continuing with
     /// recursively calling [`source`].
     ///
+    /// If you want to omit the current error and only use its sources,
+    /// use `skip(1)`.
+    ///
     /// # Examples
     ///
     /// ```
@@ -763,7 +766,7 @@ impl dyn Error {
     /// // let err : Box<Error> = b.into(); // or
     /// let err = &b as &(dyn Error);
     ///
-    /// let mut iter = err.iter_chain();
+    /// let mut iter = err.chain();
     ///
     /// assert_eq!("B".to_string(), iter.next().unwrap().to_string());
     /// assert_eq!("A".to_string(), iter.next().unwrap().to_string());
@@ -774,98 +777,27 @@ impl dyn Error {
     /// [`source`]: trait.Error.html#method.source
     #[unstable(feature = "error_iter", issue = "58520")]
     #[inline]
-    pub fn iter_chain(&self) -> ErrorIter<'_> {
-        ErrorIter {
+    pub fn chain(&self) -> Chain<'_> {
+        Chain {
             current: Some(self),
         }
     }
-
-    /// Returns an iterator starting with the [`source`] of this error
-    /// and continuing with recursively calling [`source`].
-    ///
-    /// # Examples
-    ///
-    /// ```
-    /// #![feature(error_iter)]
-    /// use std::error::Error;
-    /// use std::fmt;
-    ///
-    /// #[derive(Debug)]
-    /// struct A;
-    ///
-    /// #[derive(Debug)]
-    /// struct B(Option<Box<dyn Error + 'static>>);
-    ///
-    /// #[derive(Debug)]
-    /// struct C(Option<Box<dyn Error + 'static>>);
-    ///
-    /// impl fmt::Display for A {
-    ///     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-    ///         write!(f, "A")
-    ///     }
-    /// }
-    ///
-    /// impl fmt::Display for B {
-    ///     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-    ///         write!(f, "B")
-    ///     }
-    /// }
-    ///
-    /// impl fmt::Display for C {
-    ///     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-    ///         write!(f, "C")
-    ///     }
-    /// }
-    ///
-    /// impl Error for A {}
-    ///
-    /// impl Error for B {
-    ///     fn source(&self) -> Option<&(dyn Error + 'static)> {
-    ///         self.0.as_ref().map(|e| e.as_ref())
-    ///     }
-    /// }
-    ///
-    /// impl Error for C {
-    ///     fn source(&self) -> Option<&(dyn Error + 'static)> {
-    ///         self.0.as_ref().map(|e| e.as_ref())
-    ///     }
-    /// }
-    ///
-    /// let b = B(Some(Box::new(A)));
-    /// let c = C(Some(Box::new(b)));
-    ///
-    /// // let err : Box<Error> = c.into(); // or
-    /// let err = &c as &(dyn Error);
-    ///
-    /// let mut iter = err.iter_sources();
-    ///
-    /// assert_eq!("B".to_string(), iter.next().unwrap().to_string());
-    /// assert_eq!("A".to_string(), iter.next().unwrap().to_string());
-    /// assert!(iter.next().is_none());
-    /// assert!(iter.next().is_none());
-    /// ```
-    ///
-    /// [`source`]: trait.Error.html#method.source
-    #[inline]
-    #[unstable(feature = "error_iter", issue = "58520")]
-    pub fn iter_sources(&self) -> ErrorIter<'_> {
-        ErrorIter {
-            current: self.source(),
-        }
-    }
 }
 
-/// An iterator over [`Error`]
+/// An iterator over an [`Error`] and its sources.
+///
+/// If you want to omit the initial error and only process
+/// its sources, use `skip(1)`.
 ///
 /// [`Error`]: trait.Error.html
 #[unstable(feature = "error_iter", issue = "58520")]
 #[derive(Copy, Clone, Debug)]
-pub struct ErrorIter<'a> {
+pub struct Chain<'a> {
     current: Option<&'a (dyn Error + 'static)>,
 }
 
 #[unstable(feature = "error_iter", issue = "58520")]
-impl<'a> Iterator for ErrorIter<'a> {
+impl<'a> Iterator for Chain<'a> {
     type Item = &'a (dyn Error + 'static);
 
     fn next(&mut self) -> Option<Self::Item> {
diff --git a/src/libstd/future.rs b/src/libstd/future.rs
index c65f71fb1a4..6de3f1d545b 100644
--- a/src/libstd/future.rs
+++ b/src/libstd/future.rs
@@ -40,10 +40,11 @@ impl<T: Generator<Yield = ()>> Future for GenFuture<T> {
     fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
         // Safe because we're !Unpin + !Drop mapping to a ?Unpin value
         let gen = unsafe { Pin::map_unchecked_mut(self, |s| &mut s.0) };
-        set_task_context(cx, || match gen.resume() {
+        let _guard = unsafe { set_task_context(cx) };
+        match gen.resume() {
             GeneratorState::Yielded(()) => Poll::Pending,
             GeneratorState::Complete(x) => Poll::Ready(x),
-        })
+        }
     }
 }
 
@@ -61,35 +62,23 @@ impl Drop for SetOnDrop {
     }
 }
 
-#[doc(hidden)]
-#[unstable(feature = "gen_future", issue = "50547")]
-/// Sets the thread-local task context used by async/await futures.
-pub fn set_task_context<F, R>(cx: &mut Context<'_>, f: F) -> R
-where
-    F: FnOnce() -> R
-{
+// Safety: the returned guard must drop before `cx` is dropped and before
+// any previous guard is dropped.
+unsafe fn set_task_context(cx: &mut Context<'_>) -> SetOnDrop {
     // transmute the context's lifetime to 'static so we can store it.
-    let cx = unsafe {
-        core::mem::transmute::<&mut Context<'_>, &mut Context<'static>>(cx)
-    };
+    let cx = core::mem::transmute::<&mut Context<'_>, &mut Context<'static>>(cx);
     let old_cx = TLS_CX.with(|tls_cx| {
         tls_cx.replace(Some(NonNull::from(cx)))
     });
-    let _reset = SetOnDrop(old_cx);
-    f()
+    SetOnDrop(old_cx)
 }
 
 #[doc(hidden)]
 #[unstable(feature = "gen_future", issue = "50547")]
-/// Retrieves the thread-local task context used by async/await futures.
-///
-/// This function acquires exclusive access to the task context.
-///
-/// Panics if no context has been set or if the context has already been
-/// retrieved by a surrounding call to get_task_context.
-pub fn get_task_context<F, R>(f: F) -> R
+/// Polls a future in the current thread-local task waker.
+pub fn poll_with_tls_context<F>(f: Pin<&mut F>) -> Poll<F::Output>
 where
-    F: FnOnce(&mut Context<'_>) -> R
+    F: Future
 {
     let cx_ptr = TLS_CX.with(|tls_cx| {
         // Clear the entry so that nested `get_task_waker` calls
@@ -108,15 +97,5 @@ where
     //
     // The pointer that was inserted came from an `&mut Context<'_>`,
     // so it is safe to treat as mutable.
-    unsafe { f(cx_ptr.as_mut()) }
-}
-
-#[doc(hidden)]
-#[unstable(feature = "gen_future", issue = "50547")]
-/// Polls a future in the current thread-local task waker.
-pub fn poll_with_tls_context<F>(f: Pin<&mut F>) -> Poll<F::Output>
-where
-    F: Future
-{
-    get_task_context(|cx| F::poll(f, cx))
+    unsafe { F::poll(f, cx_ptr.as_mut()) }
 }
diff --git a/src/test/ui/async-await/issue-66387-if-without-else.rs b/src/test/ui/async-await/issue-66387-if-without-else.rs
new file mode 100644
index 00000000000..aa5a8db6121
--- /dev/null
+++ b/src/test/ui/async-await/issue-66387-if-without-else.rs
@@ -0,0 +1,10 @@
+// edition:2018
+async fn f() -> i32 {
+    if true { //~ ERROR if may be missing an else clause
+        return 0;
+    }
+    // An `if` block without `else` causes the type table not to have a type for this expr.
+    // Check that we do not unconditionally access the type table and we don't ICE.
+}
+
+fn main() {}
diff --git a/src/test/ui/async-await/issue-66387-if-without-else.stderr b/src/test/ui/async-await/issue-66387-if-without-else.stderr
new file mode 100644
index 00000000000..32952059525
--- /dev/null
+++ b/src/test/ui/async-await/issue-66387-if-without-else.stderr
@@ -0,0 +1,16 @@
+error[E0317]: if may be missing an else clause
+  --> $DIR/issue-66387-if-without-else.rs:3:5
+   |
+LL | /     if true {
+LL | |         return 0;
+LL | |     }
+   | |_____^ expected (), found i32
+   |
+   = note: expected type `()`
+              found type `i32`
+   = note: `if` expressions without `else` evaluate to `()`
+   = help: consider adding an `else` block that evaluates to the expected type
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0317`.
diff --git a/src/test/ui/consts/const-eval/assign-to-static-within-other-static.rs b/src/test/ui/consts/const-eval/assign-to-static-within-other-static.rs
index b4c416b1c55..648caae30b4 100644
--- a/src/test/ui/consts/const-eval/assign-to-static-within-other-static.rs
+++ b/src/test/ui/consts/const-eval/assign-to-static-within-other-static.rs
@@ -7,7 +7,8 @@ use std::cell::UnsafeCell;
 
 static mut FOO: u32 = 42;
 static BOO: () = unsafe {
-    FOO = 5; //~ ERROR cannot mutate statics in the initializer of another static
+    FOO = 5;
+    //~^ could not evaluate static initializer [E0080]
 };
 
 fn main() {}
diff --git a/src/test/ui/consts/const-eval/assign-to-static-within-other-static.stderr b/src/test/ui/consts/const-eval/assign-to-static-within-other-static.stderr
index 02b72765b37..cb4d35b9a18 100644
--- a/src/test/ui/consts/const-eval/assign-to-static-within-other-static.stderr
+++ b/src/test/ui/consts/const-eval/assign-to-static-within-other-static.stderr
@@ -1,8 +1,9 @@
-error: cannot mutate statics in the initializer of another static
+error[E0080]: could not evaluate static initializer
   --> $DIR/assign-to-static-within-other-static.rs:10:5
    |
 LL |     FOO = 5;
-   |     ^^^^^^^
+   |     ^^^^^^^ tried to modify a static's initial value from another static's initializer
 
 error: aborting due to previous error
 
+For more information about this error, try `rustc --explain E0080`.
diff --git a/src/test/ui/error-codes/E0017.rs b/src/test/ui/error-codes/E0017.rs
index 71250eb4621..94b6587eb81 100644
--- a/src/test/ui/error-codes/E0017.rs
+++ b/src/test/ui/error-codes/E0017.rs
@@ -4,6 +4,5 @@ const C: i32 = 2;
 const CR: &'static mut i32 = &mut C; //~ ERROR E0017
 static STATIC_REF: &'static mut i32 = &mut X; //~ ERROR E0017
                                               //~| ERROR cannot borrow
-                                              //~| ERROR cannot mutate statics
 static CONST_REF: &'static mut i32 = &mut C; //~ ERROR E0017
 fn main() {}
diff --git a/src/test/ui/error-codes/E0017.stderr b/src/test/ui/error-codes/E0017.stderr
index 67ff7da611b..47863f02214 100644
--- a/src/test/ui/error-codes/E0017.stderr
+++ b/src/test/ui/error-codes/E0017.stderr
@@ -10,12 +10,6 @@ error[E0017]: references in statics may only refer to immutable values
 LL | static STATIC_REF: &'static mut i32 = &mut X;
    |                                       ^^^^^^ statics require immutable values
 
-error: cannot mutate statics in the initializer of another static
-  --> $DIR/E0017.rs:5:39
-   |
-LL | static STATIC_REF: &'static mut i32 = &mut X;
-   |                                       ^^^^^^
-
 error[E0596]: cannot borrow immutable static item `X` as mutable
   --> $DIR/E0017.rs:5:39
    |
@@ -23,12 +17,12 @@ LL | static STATIC_REF: &'static mut i32 = &mut X;
    |                                       ^^^^^^ cannot borrow as mutable
 
 error[E0017]: references in statics may only refer to immutable values
-  --> $DIR/E0017.rs:8:38
+  --> $DIR/E0017.rs:7:38
    |
 LL | static CONST_REF: &'static mut i32 = &mut C;
    |                                      ^^^^^^ statics require immutable values
 
-error: aborting due to 5 previous errors
+error: aborting due to 4 previous errors
 
 Some errors have detailed explanations: E0017, E0596.
 For more information about an error, try `rustc --explain E0017`.
diff --git a/src/test/ui/error-codes/E0388.rs b/src/test/ui/error-codes/E0388.rs
index 817f2554ade..3aa4ac9655c 100644
--- a/src/test/ui/error-codes/E0388.rs
+++ b/src/test/ui/error-codes/E0388.rs
@@ -4,7 +4,6 @@ const C: i32 = 2;
 const CR: &'static mut i32 = &mut C; //~ ERROR E0017
 static STATIC_REF: &'static mut i32 = &mut X; //~ ERROR E0017
                                               //~| ERROR cannot borrow
-                                              //~| ERROR cannot mutate statics
 static CONST_REF: &'static mut i32 = &mut C; //~ ERROR E0017
 
 fn main() {}
diff --git a/src/test/ui/error-codes/E0388.stderr b/src/test/ui/error-codes/E0388.stderr
index e0ca4316732..b52d5260b13 100644
--- a/src/test/ui/error-codes/E0388.stderr
+++ b/src/test/ui/error-codes/E0388.stderr
@@ -10,12 +10,6 @@ error[E0017]: references in statics may only refer to immutable values
 LL | static STATIC_REF: &'static mut i32 = &mut X;
    |                                       ^^^^^^ statics require immutable values
 
-error: cannot mutate statics in the initializer of another static
-  --> $DIR/E0388.rs:5:39
-   |
-LL | static STATIC_REF: &'static mut i32 = &mut X;
-   |                                       ^^^^^^
-
 error[E0596]: cannot borrow immutable static item `X` as mutable
   --> $DIR/E0388.rs:5:39
    |
@@ -23,12 +17,12 @@ LL | static STATIC_REF: &'static mut i32 = &mut X;
    |                                       ^^^^^^ cannot borrow as mutable
 
 error[E0017]: references in statics may only refer to immutable values
-  --> $DIR/E0388.rs:8:38
+  --> $DIR/E0388.rs:7:38
    |
 LL | static CONST_REF: &'static mut i32 = &mut C;
    |                                      ^^^^^^ statics require immutable values
 
-error: aborting due to 5 previous errors
+error: aborting due to 4 previous errors
 
 Some errors have detailed explanations: E0017, E0596.
 For more information about an error, try `rustc --explain E0017`.
diff --git a/src/test/ui/issues/issue-66353.rs b/src/test/ui/issues/issue-66353.rs
new file mode 100644
index 00000000000..d8abdd5206e
--- /dev/null
+++ b/src/test/ui/issues/issue-66353.rs
@@ -0,0 +1,15 @@
+// #66353: ICE when trying to recover from incorrect associated type
+
+trait _Func<T> {
+    fn func(_: Self);
+}
+
+trait _A {
+    type AssocT;
+}
+
+fn main() {
+    _Func::< <() as _A>::AssocT >::func(());
+    //~^ ERROR the trait bound `(): _A` is not satisfied
+    //~| ERROR the trait bound `(): _Func<_>` is not satisfied
+}
diff --git a/src/test/ui/issues/issue-66353.stderr b/src/test/ui/issues/issue-66353.stderr
new file mode 100644
index 00000000000..8fd50300ca6
--- /dev/null
+++ b/src/test/ui/issues/issue-66353.stderr
@@ -0,0 +1,18 @@
+error[E0277]: the trait bound `(): _A` is not satisfied
+  --> $DIR/issue-66353.rs:12:14
+   |
+LL |     _Func::< <() as _A>::AssocT >::func(());
+   |              ^^^^^^^^^^^^^^^^^^ the trait `_A` is not implemented for `()`
+
+error[E0277]: the trait bound `(): _Func<_>` is not satisfied
+  --> $DIR/issue-66353.rs:12:41
+   |
+LL |     fn func(_: Self);
+   |     ----------------- required by `_Func::func`
+...
+LL |     _Func::< <() as _A>::AssocT >::func(());
+   |                                         ^^ the trait `_Func<_>` is not implemented for `()`
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0277`.
diff --git a/src/test/ui/label/label-beginning-with-underscore.rs b/src/test/ui/label/label-beginning-with-underscore.rs
new file mode 100644
index 00000000000..4b620864aab
--- /dev/null
+++ b/src/test/ui/label/label-beginning-with-underscore.rs
@@ -0,0 +1,10 @@
+// check-pass
+
+#![deny(unused_labels)]
+
+fn main() {
+    // `unused_label` shouldn't warn labels beginning with `_`
+    '_unused: loop {
+        break;
+    }
+}
diff --git a/src/tools/rustbook/Cargo.toml b/src/tools/rustbook/Cargo.toml
index 89bbde4d5a9..327de29037c 100644
--- a/src/tools/rustbook/Cargo.toml
+++ b/src/tools/rustbook/Cargo.toml
@@ -6,12 +6,15 @@ license = "MIT OR Apache-2.0"
 edition = "2018"
 
 [features]
-linkcheck = ["mdbook-linkcheck"]
+linkcheck = ["mdbook-linkcheck", "codespan-reporting"]
 
 [dependencies]
 clap = "2.25.0"
 failure = "0.1"
-mdbook-linkcheck = { version = "0.3.0", optional = true }
+mdbook-linkcheck = { version = "0.5.0", optional = true }
+# Keep in sync with mdbook-linkcheck.
+codespan-reporting = { version = "0.5", optional = true }
+
 
 # A noop dependency that changes in the Rust repository, it's a bit of a hack.
 # See the `src/tools/rustc-workspace-hack/README.md` file in `rust-lang/rust`
diff --git a/src/tools/rustbook/src/main.rs b/src/tools/rustbook/src/main.rs
index d5dc9a79b5a..fc283156693 100644
--- a/src/tools/rustbook/src/main.rs
+++ b/src/tools/rustbook/src/main.rs
@@ -12,8 +12,6 @@ use mdbook::MDBook;
 use failure::Error;
 #[cfg(feature = "linkcheck")]
 use mdbook::renderer::RenderContext;
-#[cfg(feature = "linkcheck")]
-use mdbook_linkcheck::{self, errors::BrokenLinks};
 
 fn main() {
     let d_message = "-d, --dest-dir=[dest-dir]
@@ -57,26 +55,7 @@ fn main() {
             {
                 if let Err(err) = linkcheck(sub_matches) {
                     eprintln!("Error: {}", err);
-
-                    // HACK: ignore timeouts
-                    let actually_broken = err
-                        .downcast::<BrokenLinks>()
-                        .map(|broken_links| {
-                            broken_links
-                                .links()
-                                .iter()
-                                .inspect(|cause| eprintln!("\tCaused By: {}", cause))
-                                .fold(false, |already_broken, cause| {
-                                    already_broken || !format!("{}", cause).contains("timed out")
-                                })
-                        })
-                        .unwrap_or(false);
-
-                    if actually_broken {
-                        std::process::exit(101);
-                    } else {
-                        std::process::exit(0);
-                    }
+                    std::process::exit(101);
                 }
             }
 
@@ -99,8 +78,9 @@ pub fn linkcheck(args: &ArgMatches<'_>) -> Result<(), Error> {
     let book = MDBook::load(&book_dir).unwrap();
     let cfg = book.config;
     let render_ctx = RenderContext::new(&book_dir, book.book, cfg, &book_dir);
-
-    mdbook_linkcheck::check_links(&render_ctx)
+    let cache_file = render_ctx.destination.join("cache.json");
+    let color = codespan_reporting::term::termcolor::ColorChoice::Auto;
+    mdbook_linkcheck::run(&cache_file, color, &render_ctx)
 }
 
 // Build command implementation
@@ -124,11 +104,7 @@ fn get_book_dir(args: &ArgMatches<'_>) -> PathBuf {
     if let Some(dir) = args.value_of("dir") {
         // Check if path is relative from current dir, or absolute...
         let p = Path::new(dir);
-        if p.is_relative() {
-            env::current_dir().unwrap().join(dir)
-        } else {
-            p.to_path_buf()
-        }
+        if p.is_relative() { env::current_dir().unwrap().join(dir) } else { p.to_path_buf() }
     } else {
         env::current_dir().unwrap()
     }
diff --git a/src/tools/tidy/src/deps.rs b/src/tools/tidy/src/deps.rs
index e6ea1c75e28..e65f7a62cac 100644
--- a/src/tools/tidy/src/deps.rs
+++ b/src/tools/tidy/src/deps.rs
@@ -55,6 +55,9 @@ const EXCEPTIONS: &[&str] = &[
     "sized-chunks",       // MPL-2.0+, cargo via im-rc
     // FIXME: this dependency violates the documentation comment above:
     "fortanix-sgx-abi",   // MPL-2.0+, libstd but only for `sgx` target
+    "dunce",              // CC0-1.0 mdbook-linkcheck
+    "codespan-reporting", // Apache-2.0 mdbook-linkcheck
+    "codespan",           // Apache-2.0 mdbook-linkcheck
 ];
 
 /// Which crates to check against the whitelist?