Auto merge of #75060 - JohnTitor:rollup-aq8sfxf, r=JohnTitor

Rollup of 10 pull requests

Successful merges:

 - #74686 (BTreeMap: remove into_slices and its unsafe block)
 - #74762 (BTreeMap::drain_filter should not touch the root during iteration)
 - #74781 (Clean up E0733 explanation)
 - #74874 (BTreeMap: define forget_type only when relevant)
 - #74974 (Make tests faster in Miri)
 - #75010 (Update elasticlunr-rs and ammonia transitive deps)
 - #75041 (Replaced log with tracing crate)
 - #75044 (Clean up E0744 explanation)
 - #75054 (Rename rustc_middle::cstore::DepKind to CrateDepKind)
 - #75057 (Avoid dumping rustc invocations to stdout)

Failed merges:

 - #74827 (Move bulk of BTreeMap::insert method down to new method on handle)

r? @ghost

30 files changed, 642 insertions, 350 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 27ce9d6bb2f..142ac9eceeb 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -37,19 +37,20 @@ version = "0.0.0"
 dependencies = [
  "compiler_builtins",
  "core",
- "rand 0.7.3",
- "rand_xorshift 0.2.0",
+ "rand",
+ "rand_xorshift",
 ]
 
 [[package]]
 name = "ammonia"
-version = "3.0.0"
+version = "3.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9e266e1f4be5ffa05309f650e2586fe1d3ae6034eb24025a7ae1dfecc330823a"
+checksum = "89eac85170f4b3fb3dc5e442c1cfb036cb8eecf9dbbd431a161ffad15d90ea3b"
 dependencies = [
  "html5ever",
  "lazy_static",
  "maplit",
+ "markup5ever_rcdom",
  "matches",
  "tendril",
  "url 2.1.0",
@@ -343,7 +344,7 @@ dependencies = [
  "termcolor",
  "toml",
  "unicode-width",
- "unicode-xid 0.2.0",
+ "unicode-xid",
  "url 2.1.0",
  "walkdir",
  "winapi 0.3.8",
@@ -444,9 +445,9 @@ version = "0.14.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d463e01905d607e181de72e8608721d3269f29176c9a14ce037011316ae7131d"
 dependencies = [
- "proc-macro2 1.0.3",
- "quote 1.0.2",
- "syn 1.0.11",
+ "proc-macro2",
+ "quote",
+ "syn",
  "synstructure",
 ]
 
@@ -547,12 +548,12 @@ dependencies = [
  "lazy_static",
  "pulldown-cmark",
  "quine-mc_cluskey",
- "quote 1.0.2",
+ "quote",
  "regex-syntax",
  "semver 0.9.0",
  "serde",
  "smallvec 1.4.0",
- "syn 1.0.11",
+ "syn",
  "toml",
  "unicode-normalization",
  "url 2.1.0",
@@ -667,7 +668,7 @@ checksum = "8ff012e225ce166d4422e0e78419d901719760f62ae2b7969ca6b564d1b54a9e"
 name = "core"
 version = "0.0.0"
 dependencies = [
- "rand 0.7.3",
+ "rand",
 ]
 
 [[package]]
@@ -788,8 +789,8 @@ version = "0.1.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "47c5e5ac752e18207b12e16b10631ae5f7f68f8805f335f9b817ead83d9ffce1"
 dependencies = [
- "quote 1.0.2",
- "syn 1.0.11",
+ "quote",
+ "syn",
 ]
 
 [[package]]
@@ -835,9 +836,9 @@ version = "0.5.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "71f31892cd5c62e414316f2963c5689242c43d8e7bbcaaeca97e5e28c95d91d9"
 dependencies = [
- "proc-macro2 1.0.3",
- "quote 1.0.2",
- "syn 1.0.11",
+ "proc-macro2",
+ "quote",
+ "syn",
 ]
 
 [[package]]
@@ -846,9 +847,9 @@ version = "0.99.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2159be042979966de68315bce7034bb000c775f22e3e834e1c52ff78f041cae8"
 dependencies = [
- "proc-macro2 1.0.3",
- "quote 1.0.2",
- "syn 1.0.11",
+ "proc-macro2",
+ "quote",
+ "syn",
 ]
 
 [[package]]
@@ -923,9 +924,9 @@ checksum = "3be565ca5c557d7f59e7cfcf1844f9e3033650c929c6566f511e8005f205c1d0"
 
 [[package]]
 name = "elasticlunr-rs"
-version = "2.3.4"
+version = "2.3.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a99a310cd1f9770e7bf8e48810c7bcbb0e078c8fb23a8c7bcf0da4c2bf61a455"
+checksum = "35622eb004c8f0c5e7e2032815f3314a93df0db30a1ce5c94e62c1ecc81e22b9"
 dependencies = [
  "lazy_static",
  "regex",
@@ -1003,9 +1004,9 @@ version = "0.1.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "aa4da3c766cd7a0db8242e326e9e4e081edd567072893ed320008189715366a4"
 dependencies = [
- "proc-macro2 1.0.3",
- "quote 1.0.2",
- "syn 1.0.11",
+ "proc-macro2",
+ "quote",
+ "syn",
  "synstructure",
 ]
 
@@ -1298,16 +1299,16 @@ dependencies = [
 
 [[package]]
 name = "html5ever"
-version = "0.24.1"
+version = "0.25.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "025483b0a1e4577bb28578318c886ee5f817dda6eb62473269349044406644cb"
+checksum = "aafcf38a1a36118242d29b92e1b08ef84e67e4a5ed06e0a80be20e6a32bfed6b"
 dependencies = [
  "log",
  "mac",
  "markup5ever",
- "proc-macro2 1.0.3",
- "quote 1.0.2",
- "syn 1.0.11",
+ "proc-macro2",
+ "quote",
+ "syn",
 ]
 
 [[package]]
@@ -1515,9 +1516,9 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8609af8f63b626e8e211f52441fcdb6ec54f1a446606b10d5c89ae9bf8a20058"
 dependencies = [
  "proc-macro-crate",
- "proc-macro2 1.0.3",
- "quote 1.0.2",
- "syn 1.0.11",
+ "proc-macro2",
+ "quote",
+ "syn",
 ]
 
 [[package]]
@@ -1735,9 +1736,9 @@ checksum = "08cbb6b4fef96b6d77bfc40ec491b1690c779e77b05cd9f07f787ed376fd4c43"
 
 [[package]]
 name = "markup5ever"
-version = "0.9.0"
+version = "0.10.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "65381d9d47506b8592b97c4efd936afcf673b09b059f2bef39c7211ee78b9d03"
+checksum = "aae38d669396ca9b707bfc3db254bc382ddb94f57cc5c235f34623a669a01dab"
 dependencies = [
  "log",
  "phf",
@@ -1751,6 +1752,18 @@ dependencies = [
 ]
 
 [[package]]
+name = "markup5ever_rcdom"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f015da43bcd8d4f144559a3423f4591d69b8ce0652c905374da7205df336ae2b"
+dependencies = [
+ "html5ever",
+ "markup5ever",
+ "tendril",
+ "xml5ever",
+]
+
+[[package]]
 name = "matchers"
 version = "0.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1937,7 +1950,7 @@ dependencies = [
  "hex 0.4.0",
  "libc",
  "log",
- "rand 0.7.3",
+ "rand",
  "rustc-workspace-hack",
  "rustc_version",
  "shell-escape",
@@ -2131,7 +2144,7 @@ dependencies = [
  "log",
  "mio-named-pipes",
  "miow 0.3.3",
- "rand 0.7.3",
+ "rand",
  "tokio",
  "tokio-named-pipes",
  "tokio-uds",
@@ -2233,9 +2246,9 @@ checksum = "99b8db626e31e5b81787b9783425769681b347011cc59471e33ea46d2ea0cf55"
 dependencies = [
  "pest",
  "pest_meta",
- "proc-macro2 1.0.3",
- "quote 1.0.2",
- "syn 1.0.11",
+ "proc-macro2",
+ "quote",
+ "syn",
 ]
 
 [[package]]
@@ -2261,18 +2274,18 @@ dependencies = [
 
 [[package]]
 name = "phf"
-version = "0.7.24"
+version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b3da44b85f8e8dfaec21adae67f95d93244b2ecf6ad2a692320598dcc8e6dd18"
+checksum = "3dfb61232e34fcb633f43d12c58f83c1df82962dcdfa565a4e866ffc17dafe12"
 dependencies = [
  "phf_shared",
 ]
 
 [[package]]
 name = "phf_codegen"
-version = "0.7.24"
+version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b03e85129e324ad4166b06b2c7491ae27fe3ec353af72e72cd1654c7225d517e"
+checksum = "cbffee61585b0411840d3ece935cce9cb6321f01c45477d30066498cd5e1a815"
 dependencies = [
  "phf_generator",
  "phf_shared",
@@ -2280,19 +2293,19 @@ dependencies = [
 
 [[package]]
 name = "phf_generator"
-version = "0.7.24"
+version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "09364cc93c159b8b06b1f4dd8a4398984503483891b0c26b867cf431fb132662"
+checksum = "17367f0cc86f2d25802b2c26ee58a7b23faeccf78a396094c13dced0d0182526"
 dependencies = [
  "phf_shared",
- "rand 0.6.1",
+ "rand",
 ]
 
 [[package]]
 name = "phf_shared"
-version = "0.7.24"
+version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "234f71a15de2288bcb7e3b6515828d22af7ec8598ee6d24c3b526fa0a80b67a0"
+checksum = "c00cf8b9eafe68dde5e9eaa2cef8ee84a9336a47d566ec55ca16589633b65af7"
 dependencies = [
  "siphasher",
 ]
@@ -2363,18 +2376,9 @@ version = "0.2.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "aeccfe4d5d8ea175d5f0e4a2ad0637e0f4121d63bd99d356fb1f39ab2e7c6097"
 dependencies = [
- "proc-macro2 1.0.3",
- "quote 1.0.2",
- "syn 1.0.11",
-]
-
-[[package]]
-name = "proc-macro2"
-version = "0.4.30"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cf3d2011ab5c909338f7887f4fc896d35932e29146c12c8d01da6b22a80ba759"
-dependencies = [
- "unicode-xid 0.1.0",
+ "proc-macro2",
+ "quote",
+ "syn",
 ]
 
 [[package]]
@@ -2383,7 +2387,7 @@ version = "1.0.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e98a83a9f9b331f54b924e68a66acb1bb35cb01fb0a23645139967abefb697e8"
 dependencies = [
- "unicode-xid 0.2.0",
+ "unicode-xid",
 ]
 
 [[package]]
@@ -2443,20 +2447,11 @@ checksum = "07589615d719a60c8dd8a4622e7946465dfef20d1a428f969e3443e7386d5f45"
 
 [[package]]
 name = "quote"
-version = "0.6.12"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "faf4799c5d274f3868a4aae320a0a182cbd2baee377b378f080e16a23e9d80db"
-dependencies = [
- "proc-macro2 0.4.30",
-]
-
-[[package]]
-name = "quote"
 version = "1.0.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "053a8c8bcc71fcce321828dc897a98ab9760bef03a4fc36693c231e5b3216cfe"
 dependencies = [
- "proc-macro2 1.0.3",
+ "proc-macro2",
 ]
 
 [[package]]
@@ -2484,44 +2479,16 @@ dependencies = [
 
 [[package]]
 name = "rand"
-version = "0.6.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ae9d223d52ae411a33cf7e54ec6034ec165df296ccd23533d671a28252b6f66a"
-dependencies = [
- "cloudabi",
- "fuchsia-zircon",
- "libc",
- "rand_chacha 0.1.0",
- "rand_core 0.3.0",
- "rand_hc 0.1.0",
- "rand_isaac",
- "rand_pcg",
- "rand_xorshift 0.1.0",
- "rustc_version",
- "winapi 0.3.8",
-]
-
-[[package]]
-name = "rand"
 version = "0.7.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6a6b1679d49b24bbfe0c803429aa1874472f50d9b363131f0e89fc356b544d03"
 dependencies = [
  "getrandom",
  "libc",
- "rand_chacha 0.2.2",
+ "rand_chacha",
  "rand_core 0.5.1",
- "rand_hc 0.2.0",
-]
-
-[[package]]
-name = "rand_chacha"
-version = "0.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "771b009e3a508cb67e8823dda454aaa5368c7bc1c16829fb77d3e980440dd34a"
-dependencies = [
- "rand_core 0.3.0",
- "rustc_version",
+ "rand_hc",
+ "rand_pcg",
 ]
 
 [[package]]
@@ -2557,15 +2524,6 @@ dependencies = [
 
 [[package]]
 name = "rand_hc"
-version = "0.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7b40677c7be09ae76218dc623efbf7b18e34bced3f38883af07bb75630a21bc4"
-dependencies = [
- "rand_core 0.3.0",
-]
-
-[[package]]
-name = "rand_hc"
 version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ca3129af7b92a17112d59ad498c6f81eaf463253766b90396d39ea7a39d6613c"
@@ -2574,15 +2532,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "rand_isaac"
-version = "0.1.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ded997c9d5f13925be2a6fd7e66bf1872597f759fd9dd93513dd7e92e5a5ee08"
-dependencies = [
- "rand_core 0.3.0",
-]
-
-[[package]]
 name = "rand_os"
 version = "0.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -2598,21 +2547,11 @@ dependencies = [
 
 [[package]]
 name = "rand_pcg"
-version = "0.1.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "086bd09a33c7044e56bb44d5bdde5a60e7f119a9e95b0775f545de759a32fe05"
-dependencies = [
- "rand_core 0.3.0",
- "rustc_version",
-]
-
-[[package]]
-name = "rand_xorshift"
-version = "0.1.0"
+version = "0.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "effa3fcaa47e18db002bdde6060944b6d2f9cfd8db471c30e873448ad9187be3"
+checksum = "16abd0c1b639e9eb4d7c50c0b8100b0d0f849be2349829c740fe8e6eb4816429"
 dependencies = [
- "rand_core 0.3.0",
+ "rand_core 0.5.1",
 ]
 
 [[package]]
@@ -2752,7 +2691,7 @@ dependencies = [
  "num_cpus",
  "ordslice",
  "racer",
- "rand 0.7.3",
+ "rand",
  "rayon",
  "regex",
  "rls-analysis",
@@ -2824,7 +2763,7 @@ dependencies = [
  "env_logger 0.7.1",
  "futures",
  "log",
- "rand 0.7.3",
+ "rand",
  "rls-data",
  "rls-ipc",
  "serde",
@@ -3051,7 +2990,7 @@ version = "669.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "456af5f09c006cf6c22c1a433ee0232c4bb74bdc6c647a010166a47c94ed2a63"
 dependencies = [
- "unicode-xid 0.2.0",
+ "unicode-xid",
 ]
 
 [[package]]
@@ -3060,9 +2999,9 @@ version = "669.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "64f6acd192f313047759a346b892998b626466b93fe04f415da5f38906bb3b4c"
 dependencies = [
- "proc-macro2 1.0.3",
- "quote 1.0.2",
- "syn 1.0.11",
+ "proc-macro2",
+ "quote",
+ "syn",
  "synstructure",
 ]
 
@@ -3224,13 +3163,13 @@ name = "rustc-workspace-hack"
 version = "1.0.0"
 dependencies = [
  "crossbeam-utils 0.7.2",
- "proc-macro2 1.0.3",
- "quote 1.0.2",
+ "proc-macro2",
+ "quote",
  "serde",
  "serde_json",
  "smallvec 0.6.10",
  "smallvec 1.4.0",
- "syn 1.0.11",
+ "syn",
  "url 2.1.0",
  "winapi 0.3.8",
 ]
@@ -3555,7 +3494,7 @@ dependencies = [
 name = "rustc_incremental"
 version = "0.0.0"
 dependencies = [
- "rand 0.7.3",
+ "rand",
  "rustc_ast",
  "rustc_data_structures",
  "rustc_fs_util",
@@ -3644,7 +3583,7 @@ dependencies = [
 name = "rustc_lexer"
 version = "0.1.0"
 dependencies = [
- "unicode-xid 0.2.0",
+ "unicode-xid",
 ]
 
 [[package]]
@@ -3681,9 +3620,9 @@ dependencies = [
 name = "rustc_macros"
 version = "0.1.0"
 dependencies = [
- "proc-macro2 1.0.3",
- "quote 1.0.2",
- "syn 1.0.11",
+ "proc-macro2",
+ "quote",
+ "syn",
  "synstructure",
 ]
 
@@ -4135,10 +4074,10 @@ dependencies = [
 name = "rustfmt-config_proc_macro"
 version = "0.2.0"
 dependencies = [
- "proc-macro2 1.0.3",
- "quote 1.0.2",
+ "proc-macro2",
+ "quote",
  "serde",
- "syn 1.0.11",
+ "syn",
 ]
 
 [[package]]
@@ -4265,9 +4204,9 @@ version = "1.0.106"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9e549e3abf4fb8621bd1609f11dfc9f5e50320802273b12f3811a67e6716ea6c"
 dependencies = [
- "proc-macro2 1.0.3",
- "quote 1.0.2",
- "syn 1.0.11",
+ "proc-macro2",
+ "quote",
+ "syn",
 ]
 
 [[package]]
@@ -4296,9 +4235,9 @@ version = "0.1.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "cd02c7587ec314570041b2754829f84d873ced14a96d1fd1823531e11db40573"
 dependencies = [
- "proc-macro2 1.0.3",
- "quote 1.0.2",
- "syn 1.0.11",
+ "proc-macro2",
+ "quote",
+ "syn",
 ]
 
 [[package]]
@@ -4346,9 +4285,9 @@ dependencies = [
 
 [[package]]
 name = "siphasher"
-version = "0.2.2"
+version = "0.3.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0df90a788073e8d0235a67e50441d47db7c8ad9debd91cbf43736a2a92d36537"
+checksum = "fa8f3741c7372e75519bd9346068370c9cdaabcc1f9599cbcf2a2719352286b7"
 
 [[package]]
 name = "sized-chunks"
@@ -4428,7 +4367,7 @@ dependencies = [
  "panic_abort",
  "panic_unwind",
  "profiler_builtins",
- "rand 0.7.3",
+ "rand",
  "rustc-demangle",
  "unwind",
  "wasi",
@@ -4436,39 +4375,30 @@ dependencies = [
 
 [[package]]
 name = "string_cache"
-version = "0.7.3"
+version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "25d70109977172b127fe834e5449e5ab1740b9ba49fa18a2020f509174f25423"
+checksum = "2940c75beb4e3bf3a494cef919a747a2cb81e52571e212bfbd185074add7208a"
 dependencies = [
  "lazy_static",
  "new_debug_unreachable",
  "phf_shared",
  "precomputed-hash",
  "serde",
- "string_cache_codegen",
- "string_cache_shared",
 ]
 
 [[package]]
 name = "string_cache_codegen"
-version = "0.4.2"
+version = "0.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1eea1eee654ef80933142157fdad9dd8bc43cf7c74e999e369263496f04ff4da"
+checksum = "f24c8e5e19d22a726626f1a5e16fe15b132dcf21d10177fa5a45ce7962996b97"
 dependencies = [
  "phf_generator",
  "phf_shared",
- "proc-macro2 0.4.30",
- "quote 0.6.12",
- "string_cache_shared",
+ "proc-macro2",
+ "quote",
 ]
 
 [[package]]
-name = "string_cache_shared"
-version = "0.3.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b1884d1bc09741d466d9b14e6d37ac89d6909cbcac41dd9ae982d4d063bbedfc"
-
-[[package]]
 name = "strip-ansi-escapes"
 version = "0.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -4501,38 +4431,27 @@ checksum = "2ae9e5165d463a0dea76967d021f8d0f9316057bf5163aa2a4843790e842ff37"
 dependencies = [
  "heck",
  "proc-macro-error",
- "proc-macro2 1.0.3",
- "quote 1.0.2",
- "syn 1.0.11",
+ "proc-macro2",
+ "quote",
+ "syn",
 ]
 
 [[package]]
 name = "strum"
-version = "0.11.0"
+version = "0.18.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f6c3a2071519ab6a48f465808c4c1ffdd00dfc8e93111d02b4fc5abab177676e"
+checksum = "57bd81eb48f4c437cadc685403cad539345bf703d78e63707418431cecd4522b"
 
 [[package]]
 name = "strum_macros"
-version = "0.11.0"
+version = "0.18.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8baacebd7b7c9b864d83a6ba7a246232983e277b86fa5cdec77f565715a4b136"
+checksum = "87c85aa3f8ea653bfd3ddf25f7ee357ee4d204731f6aa9ad04002306f6e2774c"
 dependencies = [
  "heck",
- "proc-macro2 0.4.30",
- "quote 0.6.12",
- "syn 0.15.35",
-]
-
-[[package]]
-name = "syn"
-version = "0.15.35"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "641e117d55514d6d918490e47102f7e08d096fdde360247e4a10f7a91a8478d3"
-dependencies = [
- "proc-macro2 0.4.30",
- "quote 0.6.12",
- "unicode-xid 0.1.0",
+ "proc-macro2",
+ "quote",
+ "syn",
 ]
 
 [[package]]
@@ -4541,9 +4460,9 @@ version = "1.0.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "dff0acdb207ae2fe6d5976617f887eb1e35a2ba52c13c7234c790960cdad9238"
 dependencies = [
- "proc-macro2 1.0.3",
- "quote 1.0.2",
- "unicode-xid 0.2.0",
+ "proc-macro2",
+ "quote",
+ "unicode-xid",
 ]
 
 [[package]]
@@ -4552,10 +4471,10 @@ version = "0.12.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3f085a5855930c0441ca1288cf044ea4aecf4f43a91668abdb870b4ba546a203"
 dependencies = [
- "proc-macro2 1.0.3",
- "quote 1.0.2",
- "syn 1.0.11",
- "unicode-xid 0.2.0",
+ "proc-macro2",
+ "quote",
+ "syn",
+ "unicode-xid",
 ]
 
 [[package]]
@@ -4578,7 +4497,7 @@ checksum = "7a6e24d9338a0a5be79593e2fa15a648add6138caa803e2d5bc782c371732ca9"
 dependencies = [
  "cfg-if",
  "libc",
- "rand 0.7.3",
+ "rand",
  "redox_syscall",
  "remove_dir_all",
  "winapi 0.3.8",
@@ -4683,9 +4602,9 @@ version = "1.0.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "24069c0ba08aab54289d6a25f5036d94afc61e1538bbc42ae5501df141c9027d"
 dependencies = [
- "proc-macro2 1.0.3",
- "quote 1.0.2",
- "syn 1.0.11",
+ "proc-macro2",
+ "quote",
+ "syn",
 ]
 
 [[package]]
@@ -4984,9 +4903,9 @@ version = "0.1.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f0693bf8d6f2bf22c690fc61a9d21ac69efdbb894a17ed596b9af0f01e64b84b"
 dependencies = [
- "proc-macro2 1.0.3",
- "quote 1.0.2",
- "syn 1.0.11",
+ "proc-macro2",
+ "quote",
+ "syn",
 ]
 
 [[package]]
@@ -5105,12 +5024,6 @@ dependencies = [
 
 [[package]]
 name = "unicode-xid"
-version = "0.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fc72304796d0818e357ead4e000d19c9c174ab23dc11093ac919054d20a6a7fc"
-
-[[package]]
-name = "unicode-xid"
 version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "826e7639553986605ec5979c7dd957c7895e93eabed50ab2ffa7f6128a75097c"
@@ -5297,6 +5210,18 @@ dependencies = [
 ]
 
 [[package]]
+name = "xml5ever"
+version = "0.16.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0b1b52e6e8614d4a58b8e70cf51ec0cc21b256ad8206708bcff8139b5bbd6a59"
+dependencies = [
+ "log",
+ "mac",
+ "markup5ever",
+ "time",
+]
+
+[[package]]
 name = "xz2"
 version = "0.1.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
diff --git a/library/alloc/benches/btree/map.rs b/library/alloc/benches/btree/map.rs
index 38d19c59ad1..7c2e5694a62 100644
--- a/library/alloc/benches/btree/map.rs
+++ b/library/alloc/benches/btree/map.rs
@@ -282,3 +282,305 @@ pub fn iter_10k(b: &mut Bencher) {
 pub fn iter_1m(b: &mut Bencher) {
     bench_iter(b, 1_000, 1_000_000);
 }
+
+const FAT: usize = 256;
+
+// The returned map has small keys and values.
+// Benchmarks on it have a counterpart in set.rs with the same keys and no values at all.
+fn slim_map(n: usize) -> BTreeMap<usize, usize> {
+    (0..n).map(|i| (i, i)).collect::<BTreeMap<_, _>>()
+}
+
+// The returned map has small keys and large values.
+fn fat_val_map(n: usize) -> BTreeMap<usize, [usize; FAT]> {
+    (0..n).map(|i| (i, [i; FAT])).collect::<BTreeMap<_, _>>()
+}
+
+// The returned map has large keys and values.
+fn fat_map(n: usize) -> BTreeMap<[usize; FAT], [usize; FAT]> {
+    (0..n).map(|i| ([i; FAT], [i; FAT])).collect::<BTreeMap<_, _>>()
+}
+
+#[bench]
+pub fn clone_slim_100(b: &mut Bencher) {
+    let src = slim_map(100);
+    b.iter(|| src.clone())
+}
+
+#[bench]
+pub fn clone_slim_100_and_clear(b: &mut Bencher) {
+    let src = slim_map(100);
+    b.iter(|| src.clone().clear())
+}
+
+#[bench]
+pub fn clone_slim_100_and_drain_all(b: &mut Bencher) {
+    let src = slim_map(100);
+    b.iter(|| src.clone().drain_filter(|_, _| true).count())
+}
+
+#[bench]
+pub fn clone_slim_100_and_drain_half(b: &mut Bencher) {
+    let src = slim_map(100);
+    b.iter(|| {
+        let mut map = src.clone();
+        assert_eq!(map.drain_filter(|i, _| i % 2 == 0).count(), 100 / 2);
+        assert_eq!(map.len(), 100 / 2);
+    })
+}
+
+#[bench]
+pub fn clone_slim_100_and_into_iter(b: &mut Bencher) {
+    let src = slim_map(100);
+    b.iter(|| src.clone().into_iter().count())
+}
+
+#[bench]
+pub fn clone_slim_100_and_pop_all(b: &mut Bencher) {
+    let src = slim_map(100);
+    b.iter(|| {
+        let mut map = src.clone();
+        while map.pop_first().is_some() {}
+        map
+    });
+}
+
+#[bench]
+pub fn clone_slim_100_and_remove_all(b: &mut Bencher) {
+    let src = slim_map(100);
+    b.iter(|| {
+        let mut map = src.clone();
+        while let Some(elt) = map.iter().map(|(&i, _)| i).next() {
+            let v = map.remove(&elt);
+            debug_assert!(v.is_some());
+        }
+        map
+    });
+}
+
+#[bench]
+pub fn clone_slim_100_and_remove_half(b: &mut Bencher) {
+    let src = slim_map(100);
+    b.iter(|| {
+        let mut map = src.clone();
+        for i in (0..100).step_by(2) {
+            let v = map.remove(&i);
+            debug_assert!(v.is_some());
+        }
+        assert_eq!(map.len(), 100 / 2);
+        map
+    })
+}
+
+#[bench]
+pub fn clone_slim_10k(b: &mut Bencher) {
+    let src = slim_map(10_000);
+    b.iter(|| src.clone())
+}
+
+#[bench]
+pub fn clone_slim_10k_and_clear(b: &mut Bencher) {
+    let src = slim_map(10_000);
+    b.iter(|| src.clone().clear())
+}
+
+#[bench]
+pub fn clone_slim_10k_and_drain_all(b: &mut Bencher) {
+    let src = slim_map(10_000);
+    b.iter(|| src.clone().drain_filter(|_, _| true).count())
+}
+
+#[bench]
+pub fn clone_slim_10k_and_drain_half(b: &mut Bencher) {
+    let src = slim_map(10_000);
+    b.iter(|| {
+        let mut map = src.clone();
+        assert_eq!(map.drain_filter(|i, _| i % 2 == 0).count(), 10_000 / 2);
+        assert_eq!(map.len(), 10_000 / 2);
+    })
+}
+
+#[bench]
+pub fn clone_slim_10k_and_into_iter(b: &mut Bencher) {
+    let src = slim_map(10_000);
+    b.iter(|| src.clone().into_iter().count())
+}
+
+#[bench]
+pub fn clone_slim_10k_and_pop_all(b: &mut Bencher) {
+    let src = slim_map(10_000);
+    b.iter(|| {
+        let mut map = src.clone();
+        while map.pop_first().is_some() {}
+        map
+    });
+}
+
+#[bench]
+pub fn clone_slim_10k_and_remove_all(b: &mut Bencher) {
+    let src = slim_map(10_000);
+    b.iter(|| {
+        let mut map = src.clone();
+        while let Some(elt) = map.iter().map(|(&i, _)| i).next() {
+            let v = map.remove(&elt);
+            debug_assert!(v.is_some());
+        }
+        map
+    });
+}
+
+#[bench]
+pub fn clone_slim_10k_and_remove_half(b: &mut Bencher) {
+    let src = slim_map(10_000);
+    b.iter(|| {
+        let mut map = src.clone();
+        for i in (0..10_000).step_by(2) {
+            let v = map.remove(&i);
+            debug_assert!(v.is_some());
+        }
+        assert_eq!(map.len(), 10_000 / 2);
+        map
+    })
+}
+
+#[bench]
+pub fn clone_fat_val_100(b: &mut Bencher) {
+    let src = fat_val_map(100);
+    b.iter(|| src.clone())
+}
+
+#[bench]
+pub fn clone_fat_val_100_and_clear(b: &mut Bencher) {
+    let src = fat_val_map(100);
+    b.iter(|| src.clone().clear())
+}
+
+#[bench]
+pub fn clone_fat_val_100_and_drain_all(b: &mut Bencher) {
+    let src = fat_val_map(100);
+    b.iter(|| src.clone().drain_filter(|_, _| true).count())
+}
+
+#[bench]
+pub fn clone_fat_val_100_and_drain_half(b: &mut Bencher) {
+    let src = fat_val_map(100);
+    b.iter(|| {
+        let mut map = src.clone();
+        assert_eq!(map.drain_filter(|i, _| i % 2 == 0).count(), 100 / 2);
+        assert_eq!(map.len(), 100 / 2);
+    })
+}
+
+#[bench]
+pub fn clone_fat_val_100_and_into_iter(b: &mut Bencher) {
+    let src = fat_val_map(100);
+    b.iter(|| src.clone().into_iter().count())
+}
+
+#[bench]
+pub fn clone_fat_val_100_and_pop_all(b: &mut Bencher) {
+    let src = fat_val_map(100);
+    b.iter(|| {
+        let mut map = src.clone();
+        while map.pop_first().is_some() {}
+        map
+    });
+}
+
+#[bench]
+pub fn clone_fat_val_100_and_remove_all(b: &mut Bencher) {
+    let src = fat_val_map(100);
+    b.iter(|| {
+        let mut map = src.clone();
+        while let Some(elt) = map.iter().map(|(&i, _)| i).next() {
+            let v = map.remove(&elt);
+            debug_assert!(v.is_some());
+        }
+        map
+    });
+}
+
+#[bench]
+pub fn clone_fat_val_100_and_remove_half(b: &mut Bencher) {
+    let src = fat_val_map(100);
+    b.iter(|| {
+        let mut map = src.clone();
+        for i in (0..100).step_by(2) {
+            let v = map.remove(&i);
+            debug_assert!(v.is_some());
+        }
+        assert_eq!(map.len(), 100 / 2);
+        map
+    })
+}
+
+#[bench]
+pub fn clone_fat_100(b: &mut Bencher) {
+    let src = fat_map(100);
+    b.iter(|| src.clone())
+}
+
+#[bench]
+pub fn clone_fat_100_and_clear(b: &mut Bencher) {
+    let src = fat_map(100);
+    b.iter(|| src.clone().clear())
+}
+
+#[bench]
+pub fn clone_fat_100_and_drain_all(b: &mut Bencher) {
+    let src = fat_map(100);
+    b.iter(|| src.clone().drain_filter(|_, _| true).count())
+}
+
+#[bench]
+pub fn clone_fat_100_and_drain_half(b: &mut Bencher) {
+    let src = fat_map(100);
+    b.iter(|| {
+        let mut map = src.clone();
+        assert_eq!(map.drain_filter(|i, _| i[0] % 2 == 0).count(), 100 / 2);
+        assert_eq!(map.len(), 100 / 2);
+    })
+}
+
+#[bench]
+pub fn clone_fat_100_and_into_iter(b: &mut Bencher) {
+    let src = fat_map(100);
+    b.iter(|| src.clone().into_iter().count())
+}
+
+#[bench]
+pub fn clone_fat_100_and_pop_all(b: &mut Bencher) {
+    let src = fat_map(100);
+    b.iter(|| {
+        let mut map = src.clone();
+        while map.pop_first().is_some() {}
+        map
+    });
+}
+
+#[bench]
+pub fn clone_fat_100_and_remove_all(b: &mut Bencher) {
+    let src = fat_map(100);
+    b.iter(|| {
+        let mut map = src.clone();
+        while let Some(elt) = map.iter().map(|(&i, _)| i).next() {
+            let v = map.remove(&elt);
+            debug_assert!(v.is_some());
+        }
+        map
+    });
+}
+
+#[bench]
+pub fn clone_fat_100_and_remove_half(b: &mut Bencher) {
+    let src = fat_map(100);
+    b.iter(|| {
+        let mut map = src.clone();
+        for i in (0..100).step_by(2) {
+            let v = map.remove(&[i; FAT]);
+            debug_assert!(v.is_some());
+        }
+        assert_eq!(map.len(), 100 / 2);
+        map
+    })
+}
diff --git a/library/alloc/benches/btree/set.rs b/library/alloc/benches/btree/set.rs
index 2518506b9b5..07bf5093727 100644
--- a/library/alloc/benches/btree/set.rs
+++ b/library/alloc/benches/btree/set.rs
@@ -50,27 +50,31 @@ macro_rules! set_bench {
     };
 }
 
+fn slim_set(n: usize) -> BTreeSet<usize> {
+    (0..n).collect::<BTreeSet<_>>()
+}
+
 #[bench]
 pub fn clone_100(b: &mut Bencher) {
-    let src = pos(100);
+    let src = slim_set(100);
     b.iter(|| src.clone())
 }
 
 #[bench]
 pub fn clone_100_and_clear(b: &mut Bencher) {
-    let src = pos(100);
+    let src = slim_set(100);
     b.iter(|| src.clone().clear())
 }
 
 #[bench]
 pub fn clone_100_and_drain_all(b: &mut Bencher) {
-    let src = pos(100);
+    let src = slim_set(100);
     b.iter(|| src.clone().drain_filter(|_| true).count())
 }
 
 #[bench]
 pub fn clone_100_and_drain_half(b: &mut Bencher) {
-    let src = pos(100);
+    let src = slim_set(100);
     b.iter(|| {
         let mut set = src.clone();
         assert_eq!(set.drain_filter(|i| i % 2 == 0).count(), 100 / 2);
@@ -80,13 +84,13 @@ pub fn clone_100_and_drain_half(b: &mut Bencher) {
 
 #[bench]
 pub fn clone_100_and_into_iter(b: &mut Bencher) {
-    let src = pos(100);
+    let src = slim_set(100);
     b.iter(|| src.clone().into_iter().count())
 }
 
 #[bench]
 pub fn clone_100_and_pop_all(b: &mut Bencher) {
-    let src = pos(100);
+    let src = slim_set(100);
     b.iter(|| {
         let mut set = src.clone();
         while set.pop_first().is_some() {}
@@ -96,11 +100,12 @@ pub fn clone_100_and_pop_all(b: &mut Bencher) {
 
 #[bench]
 pub fn clone_100_and_remove_all(b: &mut Bencher) {
-    let src = pos(100);
+    let src = slim_set(100);
     b.iter(|| {
         let mut set = src.clone();
         while let Some(elt) = set.iter().copied().next() {
-            set.remove(&elt);
+            let ok = set.remove(&elt);
+            debug_assert!(ok);
         }
         set
     });
@@ -108,11 +113,12 @@ pub fn clone_100_and_remove_all(b: &mut Bencher) {
 
 #[bench]
 pub fn clone_100_and_remove_half(b: &mut Bencher) {
-    let src = pos(100);
+    let src = slim_set(100);
     b.iter(|| {
         let mut set = src.clone();
-        for i in (2..=100 as i32).step_by(2) {
-            set.remove(&i);
+        for i in (0..100).step_by(2) {
+            let ok = set.remove(&i);
+            debug_assert!(ok);
         }
         assert_eq!(set.len(), 100 / 2);
         set
@@ -121,25 +127,25 @@ pub fn clone_100_and_remove_half(b: &mut Bencher) {
 
 #[bench]
 pub fn clone_10k(b: &mut Bencher) {
-    let src = pos(10_000);
+    let src = slim_set(10_000);
     b.iter(|| src.clone())
 }
 
 #[bench]
 pub fn clone_10k_and_clear(b: &mut Bencher) {
-    let src = pos(10_000);
+    let src = slim_set(10_000);
     b.iter(|| src.clone().clear())
 }
 
 #[bench]
 pub fn clone_10k_and_drain_all(b: &mut Bencher) {
-    let src = pos(10_000);
+    let src = slim_set(10_000);
     b.iter(|| src.clone().drain_filter(|_| true).count())
 }
 
 #[bench]
 pub fn clone_10k_and_drain_half(b: &mut Bencher) {
-    let src = pos(10_000);
+    let src = slim_set(10_000);
     b.iter(|| {
         let mut set = src.clone();
         assert_eq!(set.drain_filter(|i| i % 2 == 0).count(), 10_000 / 2);
@@ -149,13 +155,13 @@ pub fn clone_10k_and_drain_half(b: &mut Bencher) {
 
 #[bench]
 pub fn clone_10k_and_into_iter(b: &mut Bencher) {
-    let src = pos(10_000);
+    let src = slim_set(10_000);
     b.iter(|| src.clone().into_iter().count())
 }
 
 #[bench]
 pub fn clone_10k_and_pop_all(b: &mut Bencher) {
-    let src = pos(10_000);
+    let src = slim_set(10_000);
     b.iter(|| {
         let mut set = src.clone();
         while set.pop_first().is_some() {}
@@ -165,11 +171,12 @@ pub fn clone_10k_and_pop_all(b: &mut Bencher) {
 
 #[bench]
 pub fn clone_10k_and_remove_all(b: &mut Bencher) {
-    let src = pos(10_000);
+    let src = slim_set(10_000);
     b.iter(|| {
         let mut set = src.clone();
         while let Some(elt) = set.iter().copied().next() {
-            set.remove(&elt);
+            let ok = set.remove(&elt);
+            debug_assert!(ok);
         }
         set
     });
@@ -177,11 +184,12 @@ pub fn clone_10k_and_remove_all(b: &mut Bencher) {
 
 #[bench]
 pub fn clone_10k_and_remove_half(b: &mut Bencher) {
-    let src = pos(10_000);
+    let src = slim_set(10_000);
     b.iter(|| {
         let mut set = src.clone();
-        for i in (2..=10_000 as i32).step_by(2) {
-            set.remove(&i);
+        for i in (0..10_000).step_by(2) {
+            let ok = set.remove(&i);
+            debug_assert!(ok);
         }
         assert_eq!(set.len(), 10_000 / 2);
         set
diff --git a/library/alloc/src/collections/btree/map.rs b/library/alloc/src/collections/btree/map.rs
index 24d1f61fa68..6184051316e 100644
--- a/library/alloc/src/collections/btree/map.rs
+++ b/library/alloc/src/collections/btree/map.rs
@@ -174,7 +174,7 @@ impl<K: Clone, V: Clone> Clone for BTreeMap<K, V> {
 
                     {
                         let out_root = BTreeMap::ensure_is_owned(&mut out_tree.root);
-                        let mut out_node = out_root.push_level();
+                        let mut out_node = out_root.push_internal_level();
                         let mut in_edge = internal.first_edge();
                         while let Ok(kv) = in_edge.right_kv() {
                             let (k, v) = kv.into_kv();
@@ -1080,9 +1080,9 @@ impl<K: Ord, V> BTreeMap<K, V> {
                                 test_node = parent.forget_type();
                             }
                         }
-                        Err(node) => {
+                        Err(_) => {
                             // We are at the top, create a new root node and push there.
-                            open_node = node.into_root_mut().push_level();
+                            open_node = root.push_internal_level();
                             break;
                         }
                     }
@@ -1092,7 +1092,7 @@ impl<K: Ord, V> BTreeMap<K, V> {
                 let tree_height = open_node.height() - 1;
                 let mut right_tree = node::Root::new_leaf();
                 for _ in 0..tree_height {
-                    right_tree.push_level();
+                    right_tree.push_internal_level();
                 }
                 open_node.push(key, value, right_tree);
 
@@ -1171,7 +1171,7 @@ impl<K: Ord, V> BTreeMap<K, V> {
         let mut right = Self::new();
         let right_root = Self::ensure_is_owned(&mut right.root);
         for _ in 0..left_root.height() {
-            right_root.push_level();
+            right_root.push_internal_level();
         }
 
         {
@@ -1255,7 +1255,11 @@ impl<K: Ord, V> BTreeMap<K, V> {
     }
     pub(super) fn drain_filter_inner(&mut self) -> DrainFilterInner<'_, K, V> {
         let front = self.root.as_mut().map(|r| r.as_mut().first_leaf_edge());
-        DrainFilterInner { length: &mut self.length, cur_leaf_edge: front }
+        DrainFilterInner {
+            length: &mut self.length,
+            cur_leaf_edge: front,
+            emptied_internal_root: false,
+        }
     }
 
     /// Calculates the number of elements if it is incorrect.
@@ -1625,6 +1629,7 @@ where
 pub(super) struct DrainFilterInner<'a, K: 'a, V: 'a> {
     length: &'a mut usize,
     cur_leaf_edge: Option<Handle<NodeRef<marker::Mut<'a>, K, V, marker::Leaf>, marker::Edge>>,
+    emptied_internal_root: bool,
 }
 
 #[unstable(feature = "btree_drain_filter", issue = "70530")]
@@ -1665,6 +1670,17 @@ where
     }
 }
 
+impl<K, V> Drop for DrainFilterInner<'_, K, V> {
+    fn drop(&mut self) {
+        if self.emptied_internal_root {
+            if let Some(handle) = self.cur_leaf_edge.take() {
+                let root = handle.into_node().into_root_mut();
+                root.pop_internal_level();
+            }
+        }
+    }
+}
+
 impl<'a, K: 'a, V: 'a> DrainFilterInner<'a, K, V> {
     /// Allow Debug implementations to predict the next element.
     pub(super) fn peek(&self) -> Option<(&K, &V)> {
@@ -1681,9 +1697,10 @@ impl<'a, K: 'a, V: 'a> DrainFilterInner<'a, K, V> {
             let (k, v) = kv.kv_mut();
             if pred(k, v) {
                 *self.length -= 1;
-                let (k, v, leaf_edge_location) = kv.remove_kv_tracking();
-                self.cur_leaf_edge = Some(leaf_edge_location);
-                return Some((k, v));
+                let RemoveResult { old_kv, pos, emptied_internal_root } = kv.remove_kv_tracking();
+                self.cur_leaf_edge = Some(pos);
+                self.emptied_internal_root |= emptied_internal_root;
+                return Some(old_kv);
             }
             self.cur_leaf_edge = Some(kv.next_leaf_edge());
         }
@@ -2477,7 +2494,7 @@ impl<'a, K: Ord, V> VacantEntry<'a, K, V> {
                     }
                 },
                 Err(root) => {
-                    root.push_level().push(ins_k, ins_v, ins_edge);
+                    root.push_internal_level().push(ins_k, ins_v, ins_edge);
                     return unsafe { &mut *out_ptr };
                 }
             }
@@ -2647,20 +2664,35 @@ impl<'a, K: Ord, V> OccupiedEntry<'a, K, V> {
         self.remove_kv().1
     }
 
+    // Body of `remove_entry`, separate to keep the above implementations short.
     fn remove_kv(self) -> (K, V) {
         *self.length -= 1;
 
-        let (old_key, old_val, _) = self.handle.remove_kv_tracking();
-        (old_key, old_val)
+        let RemoveResult { old_kv, pos, emptied_internal_root } = self.handle.remove_kv_tracking();
+        let root = pos.into_node().into_root_mut();
+        if emptied_internal_root {
+            root.pop_internal_level();
+        }
+        old_kv
     }
 }
 
+struct RemoveResult<'a, K, V> {
+    // Key and value removed.
+    old_kv: (K, V),
+    // Unique location at the leaf level that the removed KV lopgically collapsed into.
+    pos: Handle<NodeRef<marker::Mut<'a>, K, V, marker::Leaf>, marker::Edge>,
+    // Whether the remove left behind and empty internal root node, that should be removed
+    // using `pop_internal_level`.
+    emptied_internal_root: bool,
+}
+
 impl<'a, K: 'a, V: 'a> Handle<NodeRef<marker::Mut<'a>, K, V, marker::LeafOrInternal>, marker::KV> {
-    /// Removes a key/value-pair from the map, and returns that pair, as well as
-    /// the leaf edge corresponding to that former pair.
-    fn remove_kv_tracking(
-        self,
-    ) -> (K, V, Handle<NodeRef<marker::Mut<'a>, K, V, marker::Leaf>, marker::Edge>) {
+    /// Removes a key/value-pair from the tree, and returns that pair, as well as
+    /// the leaf edge corresponding to that former pair. It's possible this leaves
+    /// an empty internal root node, which the caller should subsequently pop from
+    /// the map holding the tree. The caller should also decrement the map's length.
+    fn remove_kv_tracking(self) -> RemoveResult<'a, K, V> {
         let (mut pos, old_key, old_val, was_internal) = match self.force() {
             Leaf(leaf) => {
                 let (hole, old_key, old_val) = leaf.remove();
@@ -2689,6 +2721,7 @@ impl<'a, K: 'a, V: 'a> Handle<NodeRef<marker::Mut<'a>, K, V, marker::LeafOrInter
         };
 
         // Handle underflow
+        let mut emptied_internal_root = false;
         let mut cur_node = unsafe { ptr::read(&pos).into_node().forget_type() };
         let mut at_leaf = true;
         while cur_node.len() < node::MIN_LEN {
@@ -2709,8 +2742,8 @@ impl<'a, K: 'a, V: 'a> Handle<NodeRef<marker::Mut<'a>, K, V, marker::LeafOrInter
 
                     let parent = edge.into_node();
                     if parent.len() == 0 {
-                        // We must be at the root
-                        parent.into_root_mut().pop_level();
+                        // This empty parent must be the root, and should be popped off the tree.
+                        emptied_internal_root = true;
                         break;
                     } else {
                         cur_node = parent.forget_type();
@@ -2737,7 +2770,7 @@ impl<'a, K: 'a, V: 'a> Handle<NodeRef<marker::Mut<'a>, K, V, marker::LeafOrInter
             pos = unsafe { unwrap_unchecked(pos.next_kv().ok()).next_leaf_edge() };
         }
 
-        (old_key, old_val, pos)
+        RemoveResult { old_kv: (old_key, old_val), pos, emptied_internal_root }
     }
 }
 
@@ -2745,7 +2778,7 @@ impl<K, V> node::Root<K, V> {
     /// Removes empty levels on the top, but keep an empty leaf if the entire tree is empty.
     fn fix_top(&mut self) {
         while self.height() > 0 && self.as_ref().len() == 0 {
-            self.pop_level();
+            self.pop_internal_level();
         }
     }
 
@@ -2817,8 +2850,16 @@ fn handle_underfull_node<K, V>(
     let (is_left, mut handle) = match parent.left_kv() {
         Ok(left) => (true, left),
         Err(parent) => {
-            let right = unsafe { unwrap_unchecked(parent.right_kv().ok()) };
-            (false, right)
+            match parent.right_kv() {
+                Ok(right) => (false, right),
+                Err(_) => {
+                    // The underfull node has an empty parent, so it is the only child
+                    // of an empty root. It is destined to become the new root, thus
+                    // allowed to be underfull. The empty parent should be removed later
+                    // by `pop_internal_level`.
+                    return AtRoot;
+                }
+            }
         }
     };
 
diff --git a/library/alloc/src/collections/btree/navigate.rs b/library/alloc/src/collections/btree/navigate.rs
index 44f0e25bbd7..0dcb5930964 100644
--- a/library/alloc/src/collections/btree/navigate.rs
+++ b/library/alloc/src/collections/btree/navigate.rs
@@ -19,7 +19,7 @@ impl<BorrowType, K, V> Handle<NodeRef<BorrowType, K, V, marker::Leaf>, marker::E
                 Ok(internal_kv) => return Ok(internal_kv),
                 Err(last_edge) => match last_edge.into_node().ascend() {
                     Ok(parent_edge) => parent_edge.forget_node_type(),
-                    Err(root) => return Err(root.forget_type()),
+                    Err(root) => return Err(root),
                 },
             }
         }
@@ -40,7 +40,7 @@ impl<BorrowType, K, V> Handle<NodeRef<BorrowType, K, V, marker::Leaf>, marker::E
                 Ok(internal_kv) => return Ok(internal_kv),
                 Err(last_edge) => match last_edge.into_node().ascend() {
                     Ok(parent_edge) => parent_edge.forget_node_type(),
-                    Err(root) => return Err(root.forget_type()),
+                    Err(root) => return Err(root),
                 },
             }
         }
diff --git a/library/alloc/src/collections/btree/node.rs b/library/alloc/src/collections/btree/node.rs
index f7bd64608d6..b767d9ebed7 100644
--- a/library/alloc/src/collections/btree/node.rs
+++ b/library/alloc/src/collections/btree/node.rs
@@ -191,8 +191,9 @@ impl<K, V> Root<K, V> {
     }
 
     /// Adds a new internal node with a single edge, pointing to the previous root, and make that
-    /// new node the root. This increases the height by 1 and is the opposite of `pop_level`.
-    pub fn push_level(&mut self) -> NodeRef<marker::Mut<'_>, K, V, marker::Internal> {
+    /// new node the root. This increases the height by 1 and is the opposite of
+    /// `pop_internal_level`.
+    pub fn push_internal_level(&mut self) -> NodeRef<marker::Mut<'_>, K, V, marker::Internal> {
         let mut new_node = Box::new(unsafe { InternalNode::new() });
         new_node.edges[0].write(unsafe { BoxedNode::from_ptr(self.node.as_ptr()) });
 
@@ -213,11 +214,12 @@ impl<K, V> Root<K, V> {
         ret
     }
 
-    /// Removes the root node, using its first child as the new root. This cannot be called when
-    /// the tree consists only of a leaf node. As it is intended only to be called when the root
-    /// has only one edge, no cleanup is done on any of the other children of the root.
-    /// This decreases the height by 1 and is the opposite of `push_level`.
-    pub fn pop_level(&mut self) {
+    /// Removes the internal root node, using its first child as the new root.
+    /// As it is intended only to be called when the root has only one child,
+    /// no cleanup is done on any of the other children of the root.
+    /// This decreases the height by 1 and is the opposite of `push_internal_level`.
+    /// Panics if there is no internal level, i.e. if the root is a leaf.
+    pub fn pop_internal_level(&mut self) {
         assert!(self.height > 0);
 
         let top = self.node.ptr;
@@ -305,12 +307,6 @@ impl<BorrowType, K, V, Type> NodeRef<BorrowType, K, V, Type> {
         self.height
     }
 
-    /// Removes any static information about whether this node is a `Leaf` or an
-    /// `Internal` node.
-    pub fn forget_type(self) -> NodeRef<BorrowType, K, V, marker::LeafOrInternal> {
-        NodeRef { height: self.height, node: self.node, root: self.root, _marker: PhantomData }
-    }
-
     /// Temporarily takes out another, immutable reference to the same node.
     fn reborrow(&self) -> NodeRef<marker::Immut<'_>, K, V, Type> {
         NodeRef { height: self.height, node: self.node, root: self.root, _marker: PhantomData }
@@ -466,12 +462,6 @@ impl<'a, K: 'a, V: 'a, Type> NodeRef<marker::Immut<'a>, K, V, Type> {
     fn into_val_slice(self) -> &'a [V] {
         unsafe { slice::from_raw_parts(MaybeUninit::first_ptr(&self.as_leaf().vals), self.len()) }
     }
-
-    fn into_slices(self) -> (&'a [K], &'a [V]) {
-        // SAFETY: equivalent to reborrow() except not requiring Type: 'a
-        let k = unsafe { ptr::read(&self) };
-        (k.into_key_slice(), self.into_val_slice())
-    }
 }
 
 impl<'a, K: 'a, V: 'a, Type> NodeRef<marker::Mut<'a>, K, V, Type> {
@@ -980,10 +970,9 @@ impl<BorrowType, K, V> Handle<NodeRef<BorrowType, K, V, marker::Internal>, marke
 
 impl<'a, K: 'a, V: 'a, NodeType> Handle<NodeRef<marker::Immut<'a>, K, V, NodeType>, marker::KV> {
     pub fn into_kv(self) -> (&'a K, &'a V) {
-        unsafe {
-            let (keys, vals) = self.node.into_slices();
-            (keys.get_unchecked(self.idx), vals.get_unchecked(self.idx))
-        }
+        let keys = self.node.into_key_slice();
+        let vals = self.node.into_val_slice();
+        unsafe { (keys.get_unchecked(self.idx), vals.get_unchecked(self.idx)) }
     }
 }
 
@@ -1362,6 +1351,20 @@ unsafe fn move_edges<K, V>(
     }
 }
 
+impl<BorrowType, K, V> NodeRef<BorrowType, K, V, marker::Leaf> {
+    /// Removes any static information asserting that this node is a `Leaf` node.
+    pub fn forget_type(self) -> NodeRef<BorrowType, K, V, marker::LeafOrInternal> {
+        NodeRef { height: self.height, node: self.node, root: self.root, _marker: PhantomData }
+    }
+}
+
+impl<BorrowType, K, V> NodeRef<BorrowType, K, V, marker::Internal> {
+    /// Removes any static information asserting that this node is an `Internal` node.
+    pub fn forget_type(self) -> NodeRef<BorrowType, K, V, marker::LeafOrInternal> {
+        NodeRef { height: self.height, node: self.node, root: self.root, _marker: PhantomData }
+    }
+}
+
 impl<BorrowType, K, V> Handle<NodeRef<BorrowType, K, V, marker::Leaf>, marker::Edge> {
     pub fn forget_node_type(
         self,
diff --git a/library/alloc/src/collections/vec_deque/tests.rs b/library/alloc/src/collections/vec_deque/tests.rs
index e5edfe02a52..d74f91c752c 100644
--- a/library/alloc/src/collections/vec_deque/tests.rs
+++ b/library/alloc/src/collections/vec_deque/tests.rs
@@ -107,7 +107,8 @@ fn test_insert() {
     let cap = tester.capacity();
 
     // len is the length *after* insertion
-    for len in 1..cap {
+    let minlen = if cfg!(miri) { cap - 1 } else { 1 }; // Miri is too slow
+    for len in minlen..cap {
         // 0, 1, 2, .., len - 1
         let expected = (0..).take(len).collect::<VecDeque<_>>();
         for tail_pos in 0..cap {
@@ -221,7 +222,8 @@ fn test_remove() {
     let cap = tester.capacity();
 
     // len is the length *after* removal
-    for len in 0..cap - 1 {
+    let minlen = if cfg!(miri) { cap - 2 } else { 0 }; // Miri is too slow
+    for len in minlen..cap - 1 {
         // 0, 1, 2, .., len - 1
         let expected = (0..).take(len).collect::<VecDeque<_>>();
         for tail_pos in 0..cap {
@@ -251,7 +253,8 @@ fn test_range() {
     let mut tester: VecDeque<usize> = VecDeque::with_capacity(7);
 
     let cap = tester.capacity();
-    for len in 0..=cap {
+    let minlen = if cfg!(miri) { cap - 1 } else { 0 }; // Miri is too slow
+    for len in minlen..=cap {
         for tail in 0..=cap {
             for start in 0..=len {
                 for end in start..=len {
@@ -384,7 +387,8 @@ fn test_split_off() {
     let cap = tester.capacity();
 
     // len is the length *before* splitting
-    for len in 0..cap {
+    let minlen = if cfg!(miri) { cap - 1 } else { 0 }; // Miri is too slow
+    for len in minlen..cap {
         // index to split at
         for at in 0..=len {
             // 0, 1, 2, .., at - 1 (may be empty)
@@ -495,8 +499,9 @@ fn test_vec_from_vecdeque() {
 fn test_clone_from() {
     let m = vec![1; 8];
     let n = vec![2; 12];
-    for pfv in 0..8 {
-        for pfu in 0..8 {
+    let limit = if cfg!(miri) { 4 } else { 8 }; // Miri is too slow
+    for pfv in 0..limit {
+        for pfu in 0..limit {
             for longer in 0..2 {
                 let (vr, ur) = if longer == 0 { (&m, &n) } else { (&n, &m) };
                 let mut v = VecDeque::from(vr.clone());
diff --git a/library/alloc/tests/slice.rs b/library/alloc/tests/slice.rs
index 75b76bb73ed..147f7f7d0c7 100644
--- a/library/alloc/tests/slice.rs
+++ b/library/alloc/tests/slice.rs
@@ -1721,8 +1721,8 @@ fn panic_safe() {
 
     let mut rng = thread_rng();
 
-    // Miri is too slow
-    let lens = if cfg!(miri) { (1..10).chain(20..21) } else { (1..20).chain(70..MAX_LEN) };
+    // Miri is too slow (but still need to `chain` to make the types match)
+    let lens = if cfg!(miri) { (1..10).chain(0..0) } else { (1..20).chain(70..MAX_LEN) };
     let moduli: &[u32] = if cfg!(miri) { &[5] } else { &[5, 20, 50] };
 
     for len in lens {
diff --git a/library/core/tests/num/flt2dec/random.rs b/library/core/tests/num/flt2dec/random.rs
index 0ebc0881f52..e5656eb204c 100644
--- a/library/core/tests/num/flt2dec/random.rs
+++ b/library/core/tests/num/flt2dec/random.rs
@@ -188,7 +188,7 @@ fn exact_f32_random_equivalence_test() {
 fn exact_f64_random_equivalence_test() {
     use core::num::flt2dec::strategy::dragon::format_exact as fallback;
     // Miri is too slow
-    let n = if cfg!(miri) { 3 } else { 1_000 };
+    let n = if cfg!(miri) { 2 } else { 1_000 };
 
     for k in 1..21 {
         f64_random_equivalence_test(
diff --git a/library/core/tests/num/flt2dec/strategy/grisu.rs b/library/core/tests/num/flt2dec/strategy/grisu.rs
index ff8373c6455..7e6c8add333 100644
--- a/library/core/tests/num/flt2dec/strategy/grisu.rs
+++ b/library/core/tests/num/flt2dec/strategy/grisu.rs
@@ -2,6 +2,7 @@ use super::super::*;
 use core::num::flt2dec::strategy::grisu::*;
 
 #[test]
+#[cfg_attr(miri, ignore)] // Miri is too slow
 fn test_cached_power() {
     assert_eq!(CACHED_POW10.first().unwrap().1, CACHED_POW10_FIRST_E);
     assert_eq!(CACHED_POW10.last().unwrap().1, CACHED_POW10_LAST_E);
diff --git a/library/core/tests/slice.rs b/library/core/tests/slice.rs
index 27cc7fce1da..42b483f33ba 100644
--- a/library/core/tests/slice.rs
+++ b/library/core/tests/slice.rs
@@ -1358,15 +1358,15 @@ fn sort_unstable() {
     use core::slice::heapsort;
     use rand::{rngs::StdRng, seq::SliceRandom, Rng, SeedableRng};
 
-    // Miri is too slow
-    let large_range = if cfg!(miri) { 0..0 } else { 500..510 };
+    // Miri is too slow (but still need to `chain` to make the types match)
+    let lens = if cfg!(miri) { (2..20).chain(0..0) } else { (2..25).chain(500..510) };
     let rounds = if cfg!(miri) { 1 } else { 100 };
 
     let mut v = [0; 600];
     let mut tmp = [0; 600];
     let mut rng = StdRng::from_entropy();
 
-    for len in (2..25).chain(large_range) {
+    for len in lens {
         let v = &mut v[0..len];
         let tmp = &mut tmp[0..len];
 
diff --git a/src/bootstrap/bin/rustc.rs b/src/bootstrap/bin/rustc.rs
index d6649d0521c..4dd71ebade1 100644
--- a/src/bootstrap/bin/rustc.rs
+++ b/src/bootstrap/bin/rustc.rs
@@ -171,7 +171,9 @@ fn main() {
         // note: everything below here is unreachable. do not put code that
         // should run on success, after this block.
     }
-    println!("\nDid not run successfully: {}\n{:?}\n-------------", status, cmd);
+    if verbose > 0 {
+        println!("\nDid not run successfully: {}\n{:?}\n-------------", status, cmd);
+    }
 
     if let Some(mut on_fail) = on_fail {
         on_fail.status().expect("Could not run the on_fail command");
diff --git a/src/librustc_ast_lowering/Cargo.toml b/src/librustc_ast_lowering/Cargo.toml
index 51f34a1b78e..bf7e69a31ab 100644
--- a/src/librustc_ast_lowering/Cargo.toml
+++ b/src/librustc_ast_lowering/Cargo.toml
@@ -11,7 +11,7 @@ doctest = false
 
 [dependencies]
 rustc_arena = { path = "../librustc_arena" }
-log = { package = "tracing", version = "0.1" }
+tracing = "0.1"
 rustc_ast_pretty = { path = "../librustc_ast_pretty" }
 rustc_hir = { path = "../librustc_hir" }
 rustc_target = { path = "../librustc_target" }
diff --git a/src/librustc_ast_lowering/item.rs b/src/librustc_ast_lowering/item.rs
index dd5e658102f..5414e584290 100644
--- a/src/librustc_ast_lowering/item.rs
+++ b/src/librustc_ast_lowering/item.rs
@@ -17,9 +17,9 @@ use rustc_span::symbol::{kw, sym, Ident};
 use rustc_span::Span;
 use rustc_target::spec::abi;
 
-use log::debug;
 use smallvec::{smallvec, SmallVec};
 use std::collections::BTreeSet;
+use tracing::debug;
 
 pub(super) struct ItemLowerer<'a, 'lowering, 'hir> {
     pub(super) lctx: &'a mut LoweringContext<'lowering, 'hir>,
diff --git a/src/librustc_ast_lowering/lib.rs b/src/librustc_ast_lowering/lib.rs
index 1c70eef3bf5..9df7ad2a9ac 100644
--- a/src/librustc_ast_lowering/lib.rs
+++ b/src/librustc_ast_lowering/lib.rs
@@ -64,10 +64,10 @@ use rustc_span::source_map::{respan, DesugaringKind, ExpnData, ExpnKind};
 use rustc_span::symbol::{kw, sym, Ident, Symbol};
 use rustc_span::Span;
 
-use log::{debug, trace};
 use smallvec::{smallvec, SmallVec};
 use std::collections::BTreeMap;
 use std::mem;
+use tracing::{debug, trace};
 
 macro_rules! arena_vec {
     ($this:expr; $($x:expr),*) => ({
diff --git a/src/librustc_ast_lowering/path.rs b/src/librustc_ast_lowering/path.rs
index e5ce51f8d2d..2541d6824fe 100644
--- a/src/librustc_ast_lowering/path.rs
+++ b/src/librustc_ast_lowering/path.rs
@@ -12,8 +12,8 @@ use rustc_session::lint::BuiltinLintDiagnostics;
 use rustc_span::symbol::Ident;
 use rustc_span::Span;
 
-use log::debug;
 use smallvec::smallvec;
+use tracing::debug;
 
 impl<'a, 'hir> LoweringContext<'a, 'hir> {
     crate fn lower_qpath(
diff --git a/src/librustc_ast_passes/Cargo.toml b/src/librustc_ast_passes/Cargo.toml
index c53089a4afc..6db9bce3164 100644
--- a/src/librustc_ast_passes/Cargo.toml
+++ b/src/librustc_ast_passes/Cargo.toml
@@ -10,7 +10,7 @@ path = "lib.rs"
 
 [dependencies]
 itertools = "0.8"
-log = { package = "tracing", version = "0.1" }
+tracing = "0.1"
 rustc_ast_pretty = { path = "../librustc_ast_pretty" }
 rustc_attr = { path = "../librustc_attr" }
 rustc_data_structures = { path = "../librustc_data_structures" }
diff --git a/src/librustc_ast_passes/feature_gate.rs b/src/librustc_ast_passes/feature_gate.rs
index b424c8afb34..2fe208c3ce6 100644
--- a/src/librustc_ast_passes/feature_gate.rs
+++ b/src/librustc_ast_passes/feature_gate.rs
@@ -10,7 +10,7 @@ use rustc_span::source_map::Spanned;
 use rustc_span::symbol::{sym, Symbol};
 use rustc_span::Span;
 
-use log::debug;
+use tracing::debug;
 
 macro_rules! gate_feature_fn {
     ($cx: expr, $has_feature: expr, $span: expr, $name: expr, $explain: expr) => {{
diff --git a/src/librustc_ast_pretty/Cargo.toml b/src/librustc_ast_pretty/Cargo.toml
index 4035346d354..d26205c791d 100644
--- a/src/librustc_ast_pretty/Cargo.toml
+++ b/src/librustc_ast_pretty/Cargo.toml
@@ -10,7 +10,7 @@ path = "lib.rs"
 doctest = false
 
 [dependencies]
-log = { package = "tracing", version = "0.1" }
+tracing = "0.1"
 rustc_span = { path = "../librustc_span" }
 rustc_ast = { path = "../librustc_ast" }
 rustc_target = { path = "../librustc_target" }
diff --git a/src/librustc_ast_pretty/pp.rs b/src/librustc_ast_pretty/pp.rs
index 4bb806a923e..ca7f127ced6 100644
--- a/src/librustc_ast_pretty/pp.rs
+++ b/src/librustc_ast_pretty/pp.rs
@@ -132,10 +132,10 @@
 //! methods called `Printer::scan_*`, and the 'PRINT' process is the
 //! method called `Printer::print`.
 
-use log::debug;
 use std::borrow::Cow;
 use std::collections::VecDeque;
 use std::fmt;
+use tracing::debug;
 
 /// How to break. Described in more detail in the module docs.
 #[derive(Clone, Copy, PartialEq)]
diff --git a/src/librustc_error_codes/error_codes/E0733.md b/src/librustc_error_codes/error_codes/E0733.md
index 0bda7a7d682..051b75148e5 100644
--- a/src/librustc_error_codes/error_codes/E0733.md
+++ b/src/librustc_error_codes/error_codes/E0733.md
@@ -1,4 +1,6 @@
-Recursion in an `async fn` requires boxing. For example, this will not compile:
+An [`async`] function used recursion without boxing.
+
+Erroneous code example:
 
 ```edition2018,compile_fail,E0733
 async fn foo(n: usize) {
@@ -8,8 +10,8 @@ async fn foo(n: usize) {
 }
 ```
 
-To achieve async recursion, the `async fn` needs to be desugared
-such that the `Future` is explicit in the return type:
+To perform async recursion, the `async fn` needs to be desugared such that the
+`Future` is explicit in the return type:
 
 ```edition2018,compile_fail,E0720
 use std::future::Future;
@@ -36,5 +38,7 @@ fn foo_recursive(n: usize) -> Pin<Box<dyn Future<Output = ()>>> {
 }
 ```
 
-The `Box<...>` ensures that the result is of known size,
-and the pin is required to keep it in the same place in memory.
+The `Box<...>` ensures that the result is of known size, and the pin is
+required to keep it in the same place in memory.
+
+[`async`]: https://doc.rust-lang.org/std/keyword.async.html
diff --git a/src/librustc_error_codes/error_codes/E0744.md b/src/librustc_error_codes/error_codes/E0744.md
index 56b947a8282..14cff3613e0 100644
--- a/src/librustc_error_codes/error_codes/E0744.md
+++ b/src/librustc_error_codes/error_codes/E0744.md
@@ -1,7 +1,6 @@
-Control-flow expressions are not allowed inside a const context.
+A control-flow expression was used inside a const context.
 
-At the moment, `if` and `match`, as well as the looping constructs `for`,
-`while`, and `loop`, are forbidden inside a `const`, `static`, or `const fn`.
+Erroneous code example:
 
 ```compile_fail,E0744
 const _: i32 = {
@@ -13,6 +12,9 @@ const _: i32 = {
 };
 ```
 
+At the moment, `if` and `match`, as well as the looping constructs `for`,
+`while`, and `loop`, are forbidden inside a `const`, `static`, or `const fn`.
+
 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.
diff --git a/src/librustc_metadata/creader.rs b/src/librustc_metadata/creader.rs
index a4ccc8c74c8..9bc6c054e4d 100644
--- a/src/librustc_metadata/creader.rs
+++ b/src/librustc_metadata/creader.rs
@@ -13,7 +13,7 @@ use rustc_expand::base::SyntaxExtension;
 use rustc_hir::def_id::{CrateNum, LocalDefId, LOCAL_CRATE};
 use rustc_hir::definitions::Definitions;
 use rustc_index::vec::IndexVec;
-use rustc_middle::middle::cstore::{CrateSource, DepKind, ExternCrate};
+use rustc_middle::middle::cstore::{CrateDepKind, CrateSource, ExternCrate};
 use rustc_middle::middle::cstore::{ExternCrateSource, MetadataLoaderDyn};
 use rustc_middle::ty::TyCtxt;
 use rustc_session::config::{self, CrateType, ExternLocation};
@@ -306,7 +306,7 @@ impl<'a> CrateLoader<'a> {
         host_lib: Option<Library>,
         root: Option<&CratePaths>,
         lib: Library,
-        dep_kind: DepKind,
+        dep_kind: CrateDepKind,
         name: Symbol,
     ) -> Result<CrateNum, CrateError> {
         let _prof_timer = self.sess.prof.generic_activity("metadata_register_crate");
@@ -437,7 +437,7 @@ impl<'a> CrateLoader<'a> {
         &'b mut self,
         name: Symbol,
         span: Span,
-        dep_kind: DepKind,
+        dep_kind: CrateDepKind,
         dep: Option<(&'b CratePaths, &'b CrateDep)>,
     ) -> CrateNum {
         if dep.is_none() {
@@ -450,7 +450,7 @@ impl<'a> CrateLoader<'a> {
     fn maybe_resolve_crate<'b>(
         &'b mut self,
         name: Symbol,
-        mut dep_kind: DepKind,
+        mut dep_kind: CrateDepKind,
         dep: Option<(&'b CratePaths, &'b CrateDep)>,
     ) -> Result<CrateNum, CrateError> {
         info!("resolving crate `{}`", name);
@@ -487,7 +487,7 @@ impl<'a> CrateLoader<'a> {
             match self.load(&mut locator)? {
                 Some(res) => (res, None),
                 None => {
-                    dep_kind = DepKind::MacrosOnly;
+                    dep_kind = CrateDepKind::MacrosOnly;
                     match self.load_proc_macro(&mut locator, path_kind)? {
                         Some(res) => res,
                         None => return Err(locator.into_error()),
@@ -500,7 +500,7 @@ impl<'a> CrateLoader<'a> {
             (LoadResult::Previous(cnum), None) => {
                 let data = self.cstore.get_crate_data(cnum);
                 if data.is_proc_macro_crate() {
-                    dep_kind = DepKind::MacrosOnly;
+                    dep_kind = CrateDepKind::MacrosOnly;
                 }
                 data.update_dep_kind(|data_dep_kind| cmp::max(data_dep_kind, dep_kind));
                 Ok(cnum)
@@ -560,7 +560,7 @@ impl<'a> CrateLoader<'a> {
         crate_root: &CrateRoot<'_>,
         metadata: &MetadataBlob,
         krate: CrateNum,
-        dep_kind: DepKind,
+        dep_kind: CrateDepKind,
     ) -> Result<CrateNumMap, CrateError> {
         debug!("resolving deps of external crate");
         if crate_root.is_proc_macro_crate() {
@@ -579,7 +579,7 @@ impl<'a> CrateLoader<'a> {
                 dep.name, dep.hash, dep.extra_filename
             );
             let dep_kind = match dep_kind {
-                DepKind::MacrosOnly => DepKind::MacrosOnly,
+                CrateDepKind::MacrosOnly => CrateDepKind::MacrosOnly,
                 _ => dep.kind,
             };
             let cnum = self.maybe_resolve_crate(dep.name, dep_kind, Some((root, &dep)))?;
@@ -646,7 +646,7 @@ impl<'a> CrateLoader<'a> {
                 self.inject_dependency_if(cnum, "a panic runtime", &|data| {
                     data.needs_panic_runtime()
                 });
-                runtime_found = runtime_found || data.dep_kind() == DepKind::Explicit;
+                runtime_found = runtime_found || data.dep_kind() == CrateDepKind::Explicit;
             }
         });
 
@@ -675,7 +675,7 @@ impl<'a> CrateLoader<'a> {
         };
         info!("panic runtime not found -- loading {}", name);
 
-        let cnum = self.resolve_crate(name, DUMMY_SP, DepKind::Implicit, None);
+        let cnum = self.resolve_crate(name, DUMMY_SP, CrateDepKind::Implicit, None);
         let data = self.cstore.get_crate_data(cnum);
 
         // Sanity check the loaded crate to ensure it is indeed a panic runtime
@@ -705,7 +705,7 @@ impl<'a> CrateLoader<'a> {
             info!("loading profiler");
 
             let name = sym::profiler_builtins;
-            let cnum = self.resolve_crate(name, DUMMY_SP, DepKind::Implicit, None);
+            let cnum = self.resolve_crate(name, DUMMY_SP, CrateDepKind::Implicit, None);
             let data = self.cstore.get_crate_data(cnum);
 
             // Sanity check the loaded crate to ensure it is indeed a profiler runtime
@@ -901,9 +901,9 @@ impl<'a> CrateLoader<'a> {
                     None => item.ident.name,
                 };
                 let dep_kind = if attr::contains_name(&item.attrs, sym::no_link) {
-                    DepKind::MacrosOnly
+                    CrateDepKind::MacrosOnly
                 } else {
-                    DepKind::Explicit
+                    CrateDepKind::Explicit
                 };
 
                 let cnum = self.resolve_crate(name, item.span, dep_kind, None);
@@ -925,7 +925,7 @@ impl<'a> CrateLoader<'a> {
     }
 
     pub fn process_path_extern(&mut self, name: Symbol, span: Span) -> CrateNum {
-        let cnum = self.resolve_crate(name, span, DepKind::Explicit, None);
+        let cnum = self.resolve_crate(name, span, CrateDepKind::Explicit, None);
 
         self.update_extern_crate(
             cnum,
@@ -942,6 +942,6 @@ impl<'a> CrateLoader<'a> {
     }
 
     pub fn maybe_process_path_extern(&mut self, name: Symbol) -> Option<CrateNum> {
-        self.maybe_resolve_crate(name, DepKind::Explicit, None).ok()
+        self.maybe_resolve_crate(name, CrateDepKind::Explicit, None).ok()
     }
 }
diff --git a/src/librustc_metadata/dependency_format.rs b/src/librustc_metadata/dependency_format.rs
index aa5fafcc614..bb5ae4d0557 100644
--- a/src/librustc_metadata/dependency_format.rs
+++ b/src/librustc_metadata/dependency_format.rs
@@ -56,7 +56,7 @@ use crate::creader::CStore;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_hir::def_id::CrateNum;
 use rustc_middle::middle::cstore::LinkagePreference::{self, RequireDynamic, RequireStatic};
-use rustc_middle::middle::cstore::{self, DepKind};
+use rustc_middle::middle::cstore::{self, CrateDepKind};
 use rustc_middle::middle::dependency_format::{Dependencies, DependencyList, Linkage};
 use rustc_middle::ty::TyCtxt;
 use rustc_session::config::CrateType;
@@ -188,7 +188,7 @@ fn calculate_type(tcx: TyCtxt<'_>, ty: CrateType) -> DependencyList {
         let src = tcx.used_crate_source(cnum);
         if src.dylib.is_none()
             && !formats.contains_key(&cnum)
-            && tcx.dep_kind(cnum) == DepKind::Explicit
+            && tcx.dep_kind(cnum) == CrateDepKind::Explicit
         {
             assert!(src.rlib.is_some() || src.rmeta.is_some());
             log::info!("adding staticlib: {}", tcx.crate_name(cnum));
@@ -284,7 +284,7 @@ fn attempt_static(tcx: TyCtxt<'_>) -> Option<DependencyList> {
     let last_crate = tcx.crates().len();
     let mut ret = (1..last_crate + 1)
         .map(|cnum| {
-            if tcx.dep_kind(CrateNum::new(cnum)) == DepKind::Explicit {
+            if tcx.dep_kind(CrateNum::new(cnum)) == CrateDepKind::Explicit {
                 Linkage::Static
             } else {
                 Linkage::NotLinked
diff --git a/src/librustc_metadata/rmeta/decoder.rs b/src/librustc_metadata/rmeta/decoder.rs
index 414c3ad633e..3c045df45da 100644
--- a/src/librustc_metadata/rmeta/decoder.rs
+++ b/src/librustc_metadata/rmeta/decoder.rs
@@ -100,7 +100,7 @@ crate struct CrateMetadata {
     /// Same ID set as `cnum_map` plus maybe some injected crates like panic runtime.
     dependencies: Lock<Vec<CrateNum>>,
     /// How to link (or not link) this crate to the currently compiled crate.
-    dep_kind: Lock<DepKind>,
+    dep_kind: Lock<CrateDepKind>,
     /// Filesystem location of this crate.
     source: CrateSource,
     /// Whether or not this crate should be consider a private dependency
@@ -1669,7 +1669,7 @@ impl CrateMetadata {
         raw_proc_macros: Option<&'static [ProcMacro]>,
         cnum: CrateNum,
         cnum_map: CrateNumMap,
-        dep_kind: DepKind,
+        dep_kind: CrateDepKind,
         source: CrateSource,
         private_dep: bool,
         host_hash: Option<Svh>,
@@ -1727,11 +1727,11 @@ impl CrateMetadata {
         &self.source
     }
 
-    crate fn dep_kind(&self) -> DepKind {
+    crate fn dep_kind(&self) -> CrateDepKind {
         *self.dep_kind.lock()
     }
 
-    crate fn update_dep_kind(&self, f: impl FnOnce(DepKind) -> DepKind) {
+    crate fn update_dep_kind(&self, f: impl FnOnce(CrateDepKind) -> CrateDepKind) {
         self.dep_kind.with_lock(|dep_kind| *dep_kind = f(*dep_kind))
     }
 
diff --git a/src/librustc_metadata/rmeta/mod.rs b/src/librustc_metadata/rmeta/mod.rs
index 1837b86f4b5..12d2f50363c 100644
--- a/src/librustc_metadata/rmeta/mod.rs
+++ b/src/librustc_metadata/rmeta/mod.rs
@@ -11,7 +11,7 @@ use rustc_hir::def_id::{DefId, DefIndex};
 use rustc_hir::lang_items;
 use rustc_index::{bit_set::FiniteBitSet, vec::IndexVec};
 use rustc_middle::hir::exports::Export;
-use rustc_middle::middle::cstore::{DepKind, ForeignModule, LinkagePreference, NativeLib};
+use rustc_middle::middle::cstore::{CrateDepKind, ForeignModule, LinkagePreference, NativeLib};
 use rustc_middle::middle::exported_symbols::{ExportedSymbol, SymbolExportLevel};
 use rustc_middle::mir;
 use rustc_middle::ty::{self, ReprOptions, Ty};
@@ -226,7 +226,7 @@ crate struct CrateDep {
     pub name: Symbol,
     pub hash: Svh,
     pub host_hash: Option<Svh>,
-    pub kind: DepKind,
+    pub kind: CrateDepKind,
     pub extra_filename: String,
 }
 
diff --git a/src/librustc_middle/middle/cstore.rs b/src/librustc_middle/middle/cstore.rs
index 97e877df966..0a34c06adf0 100644
--- a/src/librustc_middle/middle/cstore.rs
+++ b/src/librustc_middle/middle/cstore.rs
@@ -40,7 +40,7 @@ impl CrateSource {
 
 #[derive(RustcEncodable, RustcDecodable, Copy, Clone, Ord, PartialOrd, Eq, PartialEq, Debug)]
 #[derive(HashStable)]
-pub enum DepKind {
+pub enum CrateDepKind {
     /// A dependency that is only used for its macros.
     MacrosOnly,
     /// A dependency that is always injected into the dependency list and so
@@ -51,11 +51,11 @@ pub enum DepKind {
     Explicit,
 }
 
-impl DepKind {
+impl CrateDepKind {
     pub fn macros_only(self) -> bool {
         match self {
-            DepKind::MacrosOnly => true,
-            DepKind::Implicit | DepKind::Explicit => false,
+            CrateDepKind::MacrosOnly => true,
+            CrateDepKind::Implicit | CrateDepKind::Explicit => false,
         }
     }
 }
diff --git a/src/librustc_middle/query/mod.rs b/src/librustc_middle/query/mod.rs
index 69f1366abf8..862c046358b 100644
--- a/src/librustc_middle/query/mod.rs
+++ b/src/librustc_middle/query/mod.rs
@@ -1186,7 +1186,7 @@ rustc_queries! {
     }
 
     Other {
-        query dep_kind(_: CrateNum) -> DepKind {
+        query dep_kind(_: CrateNum) -> CrateDepKind {
             eval_always
             desc { "fetching what a dependency looks like" }
         }
diff --git a/src/librustc_middle/ty/query/mod.rs b/src/librustc_middle/ty/query/mod.rs
index 2f7a9aee536..b39c0b5190a 100644
--- a/src/librustc_middle/ty/query/mod.rs
+++ b/src/librustc_middle/ty/query/mod.rs
@@ -1,10 +1,10 @@
-use crate::dep_graph::{self, DepNode, DepNodeParams};
+use crate::dep_graph::{self, DepKind, DepNode, DepNodeParams};
 use crate::hir::exports::Export;
 use crate::hir::map;
 use crate::infer::canonical::{self, Canonical};
 use crate::lint::LintLevelMap;
 use crate::middle::codegen_fn_attrs::CodegenFnAttrs;
-use crate::middle::cstore::{CrateSource, DepKind};
+use crate::middle::cstore::{CrateDepKind, CrateSource};
 use crate::middle::cstore::{ExternCrate, ForeignModule, LinkagePreference, NativeLib};
 use crate::middle::exported_symbols::{ExportedSymbol, SymbolExportLevel};
 use crate::middle::lib_features::LibFeatures;
@@ -161,7 +161,7 @@ pub fn force_from_dep_node<'tcx>(tcx: TyCtxt<'tcx>, dep_node: &DepNode) -> bool
     // hit the cache instead of having to go through `force_from_dep_node`.
     // This assertion makes sure, we actually keep applying the solution above.
     debug_assert!(
-        dep_node.kind != crate::dep_graph::DepKind::codegen_unit,
+        dep_node.kind != DepKind::codegen_unit,
         "calling force_from_dep_node() on DepKind::codegen_unit"
     );
 
@@ -172,14 +172,14 @@ pub fn force_from_dep_node<'tcx>(tcx: TyCtxt<'tcx>, dep_node: &DepNode) -> bool
     rustc_dep_node_force!([dep_node, tcx]
         // These are inputs that are expected to be pre-allocated and that
         // should therefore always be red or green already.
-        crate::dep_graph::DepKind::CrateMetadata |
+        DepKind::CrateMetadata |
 
         // These are anonymous nodes.
-        crate::dep_graph::DepKind::TraitSelect |
+        DepKind::TraitSelect |
 
         // We don't have enough information to reconstruct the query key of
         // these.
-        crate::dep_graph::DepKind::CompileCodegenUnit => {
+        DepKind::CompileCodegenUnit => {
             bug!("force_from_dep_node: encountered {:?}", dep_node)
         }
     );
diff --git a/src/tools/tidy/src/deps.rs b/src/tools/tidy/src/deps.rs
index 55e17466a88..1f988f7d81b 100644
--- a/src/tools/tidy/src/deps.rs
+++ b/src/tools/tidy/src/deps.rs
@@ -138,7 +138,6 @@ const PERMITTED_DEPENDENCIES: &[&str] = &[
     "rand_chacha",
     "rand_core",
     "rand_hc",
-    "rand_isaac",
     "rand_pcg",
     "rand_xorshift",
     "redox_syscall",