Fix errors when `parallel_compiler` is enabled

5 files changed, 83 insertions, 918 deletions

diff --git a/Cargo.lock b/Cargo.lock
index ad5ed49e360..c89a9f0da1c 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -21,12 +21,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "annotate-snippets"
-version = "0.8.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d78ea013094e5ea606b1c05fe35f1dd7ea1eb1ea259908d040b25bd5ec677ee5"
-
-[[package]]
 name = "ansi_term"
 version = "0.11.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -57,12 +51,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "arrayvec"
-version = "0.5.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cff77d8686867eceff3105329d4698d96c2391c176d5d03adc90c7389162b5b8"
-
-[[package]]
 name = "atty"
 version = "0.2.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -79,19 +67,13 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1d49d90015b3c36167a20fe2810c5cd875ad504b39cff3d4eae7977e6b7c1cb2"
 
 [[package]]
-name = "autocfg"
-version = "1.0.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cdb031dd78e28731d87d56cc8ffef4a8f36ca26c38fe2de700543e627f8a464a"
-
-[[package]]
 name = "backtrace"
 version = "0.3.40"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "924c76597f0d9ca25d762c25a4d369d51267536465dc5064bdf0eb073ed477ea"
 dependencies = [
  "backtrace-sys",
- "cfg-if 0.1.10",
+ "cfg-if",
  "libc",
  "rustc-demangle",
 ]
@@ -128,20 +110,11 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5850aeee1552f495dd0250014cf64b82b7c8879a89d83b33bbdace2cc4f63182"
 dependencies = [
  "arrayref",
- "arrayvec 0.4.12",
+ "arrayvec",
  "constant_time_eq",
 ]
 
 [[package]]
-name = "block-buffer"
-version = "0.9.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4152116fd6e9dadb291ae18fc1ec3575ed6d84c29642d97890f4b4a3417297e4"
-dependencies = [
- "generic-array",
-]
-
-[[package]]
 name = "bstr"
 version = "0.2.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -190,12 +163,6 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4785bdd1c96b2a846b2bd7cc02e86b6b3dbf14e7e53446c4f54c92a361040822"
 
 [[package]]
-name = "cfg-if"
-version = "1.0.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
-
-[[package]]
 name = "clap"
 version = "2.33.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -220,27 +187,12 @@ dependencies = [
 ]
 
 [[package]]
-name = "cloudabi"
-version = "0.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4344512281c643ae7638bbabc3af17a11307803ec8f0fcad9fae512a8bf36467"
-dependencies = [
- "bitflags",
-]
-
-[[package]]
 name = "constant_time_eq"
 version = "0.1.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "995a44c877f9212528ccc74b21a232f66ad69001e40ede5bcee2ac9ef2657120"
 
 [[package]]
-name = "cpuid-bool"
-version = "0.1.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8aebca1129a03dc6dc2b127edd729435bbc4a37e1d5f4d7513165089ceb02634"
-
-[[package]]
 name = "crossbeam-channel"
 version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -250,49 +202,12 @@ dependencies = [
 ]
 
 [[package]]
-name = "crossbeam-deque"
-version = "0.7.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9f02af974daeee82218205558e51ec8768b48cf524bd01d550abe5573a608285"
-dependencies = [
- "crossbeam-epoch",
- "crossbeam-utils 0.7.0",
- "maybe-uninit",
-]
-
-[[package]]
-name = "crossbeam-epoch"
-version = "0.8.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "058ed274caafc1f60c4997b5fc07bf7dc7cca454af7c6e81edffe5f33f70dace"
-dependencies = [
- "autocfg 1.0.1",
- "cfg-if 0.1.10",
- "crossbeam-utils 0.7.0",
- "lazy_static",
- "maybe-uninit",
- "memoffset",
- "scopeguard",
-]
-
-[[package]]
-name = "crossbeam-queue"
-version = "0.2.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "774ba60a54c213d409d5353bda12d49cd68d14e45036a285234c8d6f91f92570"
-dependencies = [
- "cfg-if 0.1.10",
- "crossbeam-utils 0.7.0",
- "maybe-uninit",
-]
-
-[[package]]
 name = "crossbeam-utils"
 version = "0.6.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "04973fa96e96579258a5091af6003abde64af786b860f18622b82e026cca60e6"
 dependencies = [
- "cfg-if 0.1.10",
+ "cfg-if",
  "lazy_static",
 ]
 
@@ -302,8 +217,8 @@ version = "0.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ce446db02cdc3165b94ae73111e570793400d0794e46125cc4056c81cbb039f4"
 dependencies = [
- "autocfg 0.1.7",
- "cfg-if 0.1.10",
+ "autocfg",
+ "cfg-if",
  "lazy_static",
 ]
 
@@ -325,21 +240,12 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3c2b69f912779fbb121ceb775d74d51e915af17aaebc38d28a592843a2dd0a3a"
 
 [[package]]
-name = "digest"
-version = "0.9.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d3dd60d1080a57a05ab032377049e0591415d2b31afd7028356dbf3cc6dcb066"
-dependencies = [
- "generic-array",
-]
-
-[[package]]
 name = "dirs"
 version = "2.0.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "13aea89a5c93364a98e9b37b2fa237effbb694d5cfe01c5b70941f7eb087d5e3"
 dependencies = [
- "cfg-if 0.1.10",
+ "cfg-if",
  "dirs-sys",
 ]
 
@@ -349,7 +255,7 @@ version = "0.3.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "afa0b23de8fd801745c471deffa6e12d248f962c9fd4b4c33787b055599bde7b"
 dependencies = [
- "cfg-if 0.1.10",
+ "cfg-if",
  "libc",
  "redox_users",
  "winapi",
@@ -362,15 +268,6 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bb1f6b1ce1c140482ea30ddd3335fc0024ac7ee112895426e0a629a6c20adfe3"
 
 [[package]]
-name = "ena"
-version = "0.14.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d7402b94a93c24e742487327a7cd839dc9d36fec9de9fb25b09f2dae459f36c3"
-dependencies = [
- "log",
-]
-
-[[package]]
 name = "env_logger"
 version = "0.6.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -418,16 +315,6 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a06f77d526c1a601b7c4cdd98f54b5eaabffc14d5f2f0296febdc7f357c6d3ba"
 
 [[package]]
-name = "generic-array"
-version = "0.14.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "501466ecc8a30d1d3b7fc9229b122b2ce8ed6e9d9223f1138d4babb253e51817"
-dependencies = [
- "typenum",
- "version_check",
-]
-
-[[package]]
 name = "getopts"
 version = "0.2.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -437,17 +324,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "getrandom"
-version = "0.1.12"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "473a1265acc8ff1e808cd0a1af8cee3c2ee5200916058a2ca113c29f2d903571"
-dependencies = [
- "cfg-if 0.1.10",
- "libc",
- "wasi",
-]
-
-[[package]]
 name = "globset"
 version = "0.4.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -461,15 +337,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "hashbrown"
-version = "0.8.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e91b62f79061a0bc2e046024cb7ba44b08419ed238ecbd9adbd787434b9e8c25"
-dependencies = [
- "autocfg 1.0.1",
-]
-
-[[package]]
 name = "heck"
 version = "0.3.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -506,25 +373,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "indexmap"
-version = "1.5.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4e47a3566dd4fd4eec714ae6ceabdee0caec795be835c223d92c2d40f1e8cf1c"
-dependencies = [
- "autocfg 1.0.1",
- "hashbrown",
-]
-
-[[package]]
-name = "instant"
-version = "0.1.7"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "63312a18f7ea8760cdd0a7c5aac1a619752a246b833545e3e36d1f81f7cd9e66"
-dependencies = [
- "cfg-if 0.1.10",
-]
-
-[[package]]
 name = "itertools"
 version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -534,32 +382,12 @@ dependencies = [
 ]
 
 [[package]]
-name = "itertools"
-version = "0.9.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "284f18f85651fe11e8a991b2adb42cb078325c996ed026d994719efcfca1d54b"
-dependencies = [
- "either",
-]
-
-[[package]]
 name = "itoa"
 version = "0.4.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "501266b7edd0174f8530248f87f99c88fbe60ca4ef3dd486835b8d8d53136f7f"
 
 [[package]]
-name = "jobserver"
-version = "0.1.17"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f2b1d42ef453b30b7387e113da1c83ab1605d90c5b4e0eb8e96d016ed3b8c160"
-dependencies = [
- "getrandom",
- "libc",
- "log",
-]
-
-[[package]]
 name = "lazy_static"
 version = "1.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -572,52 +400,12 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f2f96b10ec2560088a8e76961b00d47107b3a625fecb76dedb29ee7ccbf98235"
 
 [[package]]
-name = "lock_api"
-version = "0.4.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "28247cc5a5be2f05fbcd76dd0cf2c7d3b5400cb978a28042abcd4fa0b3f8261c"
-dependencies = [
- "scopeguard",
-]
-
-[[package]]
 name = "log"
 version = "0.4.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "14b6052be84e6b71ab17edffc2eeabf5c2c3ae1fdb464aae35ac50c67a44e1f7"
 dependencies = [
- "cfg-if 0.1.10",
-]
-
-[[package]]
-name = "maybe-uninit"
-version = "2.0.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "60302e4db3a61da70c0cb7991976248362f30319e88850c487b9b95bbf059e00"
-
-[[package]]
-name = "md-5"
-version = "0.9.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7b5a279bb9607f9f53c22d496eade00d138d1bdcccd07d74650387cf94942a15"
-dependencies = [
- "block-buffer",
- "digest",
- "opaque-debug",
-]
-
-[[package]]
-name = "measureme"
-version = "9.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4a98e07fe802486895addb2b5467f33f205e82c426bfaf350f5d8109b137767c"
-dependencies = [
- "log",
- "memmap",
- "parking_lot",
- "perf-event-open-sys",
- "rustc-hash",
- "smallvec",
+ "cfg-if",
 ]
 
 [[package]]
@@ -627,96 +415,21 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "88579771288728879b57485cc7d6b07d648c9f0141eb955f8ab7f9d45394468e"
 
 [[package]]
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-version = "0.7.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6585fd95e7bb50d6cc31e20d4cf9afb4e2ba16c5846fc76793f11218da9c475b"
-dependencies = [
- "libc",
- "winapi",
-]
-
-[[package]]
-name = "memoffset"
-version = "0.5.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ce6075db033bbbb7ee5a0bbd3a3186bbae616f57fb001c485c7ff77955f8177f"
-dependencies = [
- "rustc_version",
-]
-
-[[package]]
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 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "72ef4a56884ca558e5ddb05a1d1e7e1bfd9a68d9ed024c21704cc98872dae1bb"
 
 [[package]]
-name = "num_cpus"
-version = "1.10.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bcef43580c035376c0705c42792c294b66974abbfd2789b511784023f71f3273"
-dependencies = [
- "libc",
-]
-
-[[package]]
-name = "opaque-debug"
-version = "0.3.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "624a8340c38c1b80fd549087862da4ba43e08858af025b236e509b6649fc13d5"
-
-[[package]]
 name = "packed_simd"
 version = "0.3.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a85ea9fc0d4ac0deb6fe7911d38786b32fc11119afd9e9d38b84ff691ce64220"
 dependencies = [
- "cfg-if 0.1.10",
-]
-
-[[package]]
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-version = "0.11.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a4893845fa2ca272e647da5d0e46660a314ead9c2fdd9a883aabc32e481a8733"
-dependencies = [
- "instant",
- "lock_api",
- "parking_lot_core",
+ "cfg-if",
 ]
 
 [[package]]
-name = "parking_lot_core"
-version = "0.8.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c361aa727dd08437f2f1447be8b59a33b0edd15e0fcee698f935613d9efbca9b"
-dependencies = [
- "cfg-if 0.1.10",
- "cloudabi 0.1.0",
- "instant",
- "libc",
- "redox_syscall",
- "smallvec",
- "winapi",
-]
-
-[[package]]
-name = "perf-event-open-sys"
-version = "1.0.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ce9bedf5da2c234fdf2391ede2b90fabf585355f33100689bc364a3ea558561a"
-dependencies = [
- "libc",
-]
-
-[[package]]
-name = "ppv-lite86"
-version = "0.2.9"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c36fa947111f5c62a733b652544dd0016a43ce89619538a8ef92724a6f501a20"
-
-[[package]]
 name = "proc-macro-error"
 version = "0.4.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -752,15 +465,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "psm"
-version = "0.1.8"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "659ecfea2142a458893bb7673134bad50b752fea932349c213d6a23874ce3aa7"
-dependencies = [
- "cc",
-]
-
-[[package]]
 name = "quick-error"
 version = "1.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -776,29 +480,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "rand"
-version = "0.7.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6a6b1679d49b24bbfe0c803429aa1874472f50d9b363131f0e89fc356b544d03"
-dependencies = [
- "getrandom",
- "libc",
- "rand_chacha",
- "rand_core 0.5.1",
- "rand_hc",
-]
-
-[[package]]
-name = "rand_chacha"
-version = "0.2.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f4c8ed856279c9737206bf725bf36935d8666ead7aa69b52be55af369d193402"
-dependencies = [
- "ppv-lite86",
- "rand_core 0.5.1",
-]
-
-[[package]]
 name = "rand_core"
 version = "0.3.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -814,30 +495,12 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9c33a3c44ca05fa6f1807d8e6743f3824e8509beca625669633be0acbdf509dc"
 
 [[package]]
-name = "rand_core"
-version = "0.5.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "90bde5296fc891b0cef12a6d03ddccc162ce7b2aff54160af9338f8d40df6d19"
-dependencies = [
- "getrandom",
-]
-
-[[package]]
-name = "rand_hc"
-version = "0.2.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ca3129af7b92a17112d59ad498c6f81eaf463253766b90396d39ea7a39d6613c"
-dependencies = [
- "rand_core 0.5.1",
-]
-
-[[package]]
 name = "rand_os"
 version = "0.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7b75f676a1e053fc562eafbb47838d67c84801e38fc1ba459e8f180deabd5071"
 dependencies = [
- "cloudabi 0.0.3",
+ "cloudabi",
  "fuchsia-cprng",
  "libc",
  "rand_core 0.4.2",
@@ -891,15 +554,6 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "11a7e20d1cce64ef2fed88b66d347f88bd9babb82845b2b858f3edbf59a4f716"
 
 [[package]]
-name = "remove_dir_all"
-version = "0.5.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3acd125665422973a33ac9d3dd2df85edad0f4ae9b00dafb1a05e43a9f5ef8e7"
-dependencies = [
- "winapi",
-]
-
-[[package]]
 name = "rust-argon2"
 version = "0.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -911,363 +565,18 @@ dependencies = [
 ]
 
 [[package]]
-name = "rustc-ap-rustc_arena"
-version = "712.0.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "259cca0e975ecb05fd289ace45280c30ff792efc04e856a7f18b7fc86a3cb610"
-dependencies = [
- "rustc-ap-rustc_data_structures",
- "smallvec",
-]
-
-[[package]]
-name = "rustc-ap-rustc_ast"
-version = "712.0.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bb9be435d50c88e94bbad6ea468c8680b52c5043bb298ab8058d05251717f8f8"
-dependencies = [
- "bitflags",
- "rustc-ap-rustc_data_structures",
- "rustc-ap-rustc_index",
- "rustc-ap-rustc_lexer",
- "rustc-ap-rustc_macros",
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- "rustc-ap-rustc_macros",
- "rustc-ap-rustc_serialize",
- "rustc-ap-rustc_session",
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- "libc",
- "measureme",
- "parking_lot",
- "rustc-ap-rustc_graphviz",
- "rustc-ap-rustc_index",
- "rustc-ap-rustc_macros",
- "rustc-ap-rustc_serialize",
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- "rustc-rayon",
- "rustc-rayon-core",
- "smallvec",
- "stable_deref_trait",
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- "tempfile",
- "tracing",
- "winapi",
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- "rustc-ap-rustc_serialize",
- "rustc-ap-rustc_span",
- "termcolor",
- "termize",
- "tracing",
- "unicode-width",
- "winapi",
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-name = "rustc-ap-rustc_expand"
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- "rustc-ap-rustc_data_structures",
- "rustc-ap-rustc_errors",
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- "rustc-ap-rustc_parse",
- "rustc-ap-rustc_serialize",
- "rustc-ap-rustc_session",
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- "smallvec",
- "tracing",
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-[[package]]
-name = "rustc-ap-rustc_feature"
-version = "712.0.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
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-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ffffffdef9fd51db69c1d4c045ced8aaab999be5627f2d3a0ce020d74c1f1e50"
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- "rustc-ap-rustc_lexer",
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- "unicode-normalization",
-]
-
-[[package]]
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-dependencies = [
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- "smallvec",
-]
-
-[[package]]
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-dependencies = [
- "bitflags",
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- "rustc-ap-rustc_ast",
- "rustc-ap-rustc_data_structures",
- "rustc-ap-rustc_errors",
- "rustc-ap-rustc_feature",
- "rustc-ap-rustc_fs_util",
- "rustc-ap-rustc_lint_defs",
- "rustc-ap-rustc_macros",
- "rustc-ap-rustc_serialize",
- "rustc-ap-rustc_span",
- "rustc-ap-rustc_target",
- "tracing",
-]
-
-[[package]]
-name = "rustc-ap-rustc_span"
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-source = "registry+https://github.com/rust-lang/crates.io-index"
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-dependencies = [
- "cfg-if 0.1.10",
- "md-5",
- "rustc-ap-rustc_arena",
- "rustc-ap-rustc_data_structures",
- "rustc-ap-rustc_index",
- "rustc-ap-rustc_macros",
- "rustc-ap-rustc_serialize",
- "scoped-tls",
- "sha-1",
- "sha2",
- "tracing",
- "unicode-width",
-]
-
-[[package]]
-name = "rustc-ap-rustc_target"
-version = "712.0.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0a8329d92e7dc24b974f759e6c6e97e2bbc47b18d0573343028f8135ca367200"
-dependencies = [
- "bitflags",
- "rustc-ap-rustc_data_structures",
- "rustc-ap-rustc_index",
- "rustc-ap-rustc_macros",
- "rustc-ap-rustc_serialize",
- "rustc-ap-rustc_span",
- "tracing",
-]
-
-[[package]]
 name = "rustc-demangle"
 version = "0.1.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4c691c0e608126e00913e33f0ccf3727d5fc84573623b8d65b2df340b5201783"
 
 [[package]]
-name = "rustc-hash"
-version = "1.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "08d43f7aa6b08d49f382cde6a7982047c3426db949b1424bc4b7ec9ae12c6ce2"
-
-[[package]]
-name = "rustc-rayon"
-version = "0.3.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ed7d6a39f8bfd4421ce720918234d1e672b83824c91345b47c93746839cf1629"
-dependencies = [
- "crossbeam-deque",
- "either",
- "rustc-rayon-core",
-]
-
-[[package]]
-name = "rustc-rayon-core"
-version = "0.3.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e94187d9ea3e8c38fafdbc38acb94eafa7ce155867f6ccb13830466a0d0db8c6"
-dependencies = [
- "crossbeam-deque",
- "crossbeam-queue",
- "crossbeam-utils 0.7.0",
- "lazy_static",
- "num_cpus",
-]
-
-[[package]]
 name = "rustc-workspace-hack"
 version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "fc71d2faa173b74b232dedc235e3ee1696581bb132fc116fa3626d6151a1a8fb"
 
 [[package]]
-name = "rustc_version"
-version = "0.2.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "138e3e0acb6c9fb258b19b67cb8abd63c00679d2851805ea151465464fe9030a"
-dependencies = [
- "semver",
-]
-
-[[package]]
 name = "rustfmt-config_proc_macro"
 version = "0.2.0"
 dependencies = [
@@ -1280,7 +589,7 @@ dependencies = [
 name = "rustfmt-nightly"
 version = "1.4.37"
 dependencies = [
- "annotate-snippets 0.6.1",
+ "annotate-snippets",
  "anyhow",
  "bytecount",
  "cargo_metadata",
@@ -1290,18 +599,10 @@ dependencies = [
  "env_logger",
  "getopts",
  "ignore",
- "itertools 0.8.0",
+ "itertools",
  "lazy_static",
  "log",
  "regex",
- "rustc-ap-rustc_ast",
- "rustc-ap-rustc_ast_pretty",
- "rustc-ap-rustc_data_structures",
- "rustc-ap-rustc_errors",
- "rustc-ap-rustc_expand",
- "rustc-ap-rustc_parse",
- "rustc-ap-rustc_session",
- "rustc-ap-rustc_span",
  "rustc-workspace-hack",
  "rustfmt-config_proc_macro",
  "serde",
@@ -1331,18 +632,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "scoped-tls"
-version = "1.0.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ea6a9290e3c9cf0f18145ef7ffa62d68ee0bf5fcd651017e586dc7fd5da448c2"
-
-[[package]]
-name = "scopeguard"
-version = "1.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d29ab0c6d3fc0ee92fe66e2d99f700eab17a8d57d1c1d3b748380fb20baa78cd"
-
-[[package]]
 name = "semver"
 version = "0.9.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1390,57 +679,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "sha-1"
-version = "0.9.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ce3cdf1b5e620a498ee6f2a171885ac7e22f0e12089ec4b3d22b84921792507c"
-dependencies = [
- "block-buffer",
- "cfg-if 1.0.0",
- "cpuid-bool",
- "digest",
- "opaque-debug",
-]
-
-[[package]]
-name = "sha2"
-version = "0.9.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6e7aab86fe2149bad8c507606bdb3f4ef5e7b2380eb92350f56122cca72a42a8"
-dependencies = [
- "block-buffer",
- "cfg-if 1.0.0",
- "cpuid-bool",
- "digest",
- "opaque-debug",
-]
-
-[[package]]
-name = "smallvec"
-version = "1.6.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fe0f37c9e8f3c5a4a66ad655a93c74daac4ad00c441533bf5c6e7990bb42604e"
-
-[[package]]
-name = "stable_deref_trait"
-version = "1.1.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "dba1a27d3efae4351c8051072d619e3ade2820635c3958d826bfea39d59b54c8"
-
-[[package]]
-name = "stacker"
-version = "0.1.12"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "21ccb4c06ec57bc82d0f610f1a2963d7648700e43a6f513e564b9c89f7991786"
-dependencies = [
- "cc",
- "cfg-if 0.1.10",
- "libc",
- "psm",
- "winapi",
-]
-
-[[package]]
 name = "strsim"
 version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1505,20 +743,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "tempfile"
-version = "3.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7a6e24d9338a0a5be79593e2fa15a648add6138caa803e2d5bc782c371732ca9"
-dependencies = [
- "cfg-if 0.1.10",
- "libc",
- "rand",
- "redox_syscall",
- "remove_dir_all",
- "winapi",
-]
-
-[[package]]
 name = "term"
 version = "0.6.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1538,16 +762,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "termize"
-version = "0.1.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1706be6b564323ce7092f5f7e6b118a14c8ef7ed0e69c8c5329c914a9f101295"
-dependencies = [
- "libc",
- "winapi",
-]
-
-[[package]]
 name = "textwrap"
 version = "0.11.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1604,52 +818,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "tracing"
-version = "0.1.19"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6d79ca061b032d6ce30c660fded31189ca0b9922bf483cd70759f13a2d86786c"
-dependencies = [
- "cfg-if 0.1.10",
- "tracing-attributes",
- "tracing-core",
-]
-
-[[package]]
-name = "tracing-attributes"
-version = "0.1.11"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "80e0ccfc3378da0cce270c946b676a376943f5cd16aeba64568e7939806f4ada"
-dependencies = [
- "proc-macro2",
- "quote",
- "syn",
-]
-
-[[package]]
-name = "tracing-core"
-version = "0.1.15"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4f0e00789804e99b20f12bc7003ca416309d28a6f495d6af58d1e2c2842461b5"
-dependencies = [
- "lazy_static",
-]
-
-[[package]]
-name = "typenum"
-version = "1.12.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "373c8a200f9e67a0c95e62a4f52fbf80c23b4381c05a17845531982fa99e6b33"
-
-[[package]]
-name = "unicode-normalization"
-version = "0.1.12"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5479532badd04e128284890390c1e876ef7a993d0570b3597ae43dfa1d59afa4"
-dependencies = [
- "smallvec",
-]
-
-[[package]]
 name = "unicode-segmentation"
 version = "1.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1697,12 +865,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "wasi"
-version = "0.7.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b89c3ce4ce14bdc6fb6beaf9ec7928ca331de5df7e5ea278375642a2f478570d"
-
-[[package]]
 name = "winapi"
 version = "0.3.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
diff --git a/src/config/file_lines.rs b/src/config/file_lines.rs
index 18ae2fd2c47..95e5d0c9153 100644
--- a/src/config/file_lines.rs
+++ b/src/config/file_lines.rs
@@ -3,9 +3,9 @@
 use itertools::Itertools;
 use std::collections::HashMap;
 use std::path::PathBuf;
-use std::rc::Rc;
 use std::{cmp, fmt, iter, str};
 
+use rustc_data_structures::sync::Lrc;
 use rustc_span::{self, SourceFile};
 use serde::{ser, Deserialize, Deserializer, Serialize, Serializer};
 use serde_json as json;
@@ -13,7 +13,7 @@ use thiserror::Error;
 
 /// A range of lines in a file, inclusive of both ends.
 pub struct LineRange {
-    pub file: Rc<SourceFile>,
+    pub file: Lrc<SourceFile>,
     pub lo: usize,
     pub hi: usize,
 }
diff --git a/src/source_file.rs b/src/source_file.rs
index 1d22c25d922..052b0f9c5d6 100644
--- a/src/source_file.rs
+++ b/src/source_file.rs
@@ -13,7 +13,8 @@ use crate::config::Config;
 use crate::create_emitter;
 #[cfg(test)]
 use crate::formatting::FileRecord;
-use std::rc::Rc;
+
+use rustc_data_structures::sync::Lrc;
 
 // Append a newline to the end of each file.
 pub(crate) fn append_newline(s: &mut String) {
@@ -86,11 +87,11 @@ where
     // source map instead of hitting the file system. This also supports getting
     // original text for `FileName::Stdin`.
     let original_text = if newline_style != NewlineStyle::Auto && *filename != FileName::Stdin {
-        Rc::new(fs::read_to_string(ensure_real_path(filename))?)
+        Lrc::new(fs::read_to_string(ensure_real_path(filename))?)
     } else {
         match parse_sess.and_then(|sess| sess.get_original_snippet(filename)) {
             Some(ori) => ori,
-            None => Rc::new(fs::read_to_string(ensure_real_path(filename))?),
+            None => Lrc::new(fs::read_to_string(ensure_real_path(filename))?),
         }
     };
 
diff --git a/src/syntux/session.rs b/src/syntux/session.rs
index 374d08f7f23..b17a655c1cb 100644
--- a/src/syntux/session.rs
+++ b/src/syntux/session.rs
@@ -1,6 +1,5 @@
-use std::cell::RefCell;
 use std::path::Path;
-use std::rc::Rc;
+use std::sync::atomic::{AtomicBool, Ordering};
 
 use rustc_data_structures::sync::{Lrc, Send};
 use rustc_errors::emitter::{Emitter, EmitterWriter};
@@ -21,8 +20,8 @@ use crate::{Config, ErrorKind, FileName};
 /// ParseSess holds structs necessary for constructing a parser.
 pub(crate) struct ParseSess {
     parse_sess: RawParseSess,
-    ignore_path_set: Rc<IgnorePathSet>,
-    can_reset_errors: Rc<RefCell<bool>>,
+    ignore_path_set: Lrc<IgnorePathSet>,
+    can_reset_errors: Lrc<AtomicBool>,
 }
 
 /// Emitter which discards every error.
@@ -41,17 +40,17 @@ fn silent_emitter() -> Box<dyn Emitter + Send> {
 
 /// Emit errors against every files expect ones specified in the `ignore_path_set`.
 struct SilentOnIgnoredFilesEmitter {
-    ignore_path_set: Rc<IgnorePathSet>,
-    source_map: Rc<SourceMap>,
+    ignore_path_set: Lrc<IgnorePathSet>,
+    source_map: Lrc<SourceMap>,
     emitter: Box<dyn Emitter + Send>,
     has_non_ignorable_parser_errors: bool,
-    can_reset: Rc<RefCell<bool>>,
+    can_reset: Lrc<AtomicBool>,
 }
 
 impl SilentOnIgnoredFilesEmitter {
     fn handle_non_ignoreable_error(&mut self, db: &Diagnostic) {
         self.has_non_ignorable_parser_errors = true;
-        *self.can_reset.borrow_mut() = false;
+        self.can_reset.store(false, Ordering::Release);
         self.emitter.emit_diagnostic(db);
     }
 }
@@ -73,7 +72,7 @@ impl Emitter for SilentOnIgnoredFilesEmitter {
                     .is_match(&FileName::Real(path.to_path_buf()))
                 {
                     if !self.has_non_ignorable_parser_errors {
-                        *self.can_reset.borrow_mut() = true;
+                        self.can_reset.store(true, Ordering::Release);
                     }
                     return;
                 }
@@ -84,9 +83,9 @@ impl Emitter for SilentOnIgnoredFilesEmitter {
 }
 
 fn default_handler(
-    source_map: Rc<SourceMap>,
-    ignore_path_set: Rc<IgnorePathSet>,
-    can_reset: Rc<RefCell<bool>>,
+    source_map: Lrc<SourceMap>,
+    ignore_path_set: Lrc<IgnorePathSet>,
+    can_reset: Lrc<AtomicBool>,
     hide_parse_errors: bool,
 ) -> Handler {
     let supports_color = term::stderr().map_or(false, |term| term.supports_color());
@@ -124,16 +123,16 @@ fn default_handler(
 impl ParseSess {
     pub(crate) fn new(config: &Config) -> Result<ParseSess, ErrorKind> {
         let ignore_path_set = match IgnorePathSet::from_ignore_list(&config.ignore()) {
-            Ok(ignore_path_set) => Rc::new(ignore_path_set),
+            Ok(ignore_path_set) => Lrc::new(ignore_path_set),
             Err(e) => return Err(ErrorKind::InvalidGlobPattern(e)),
         };
-        let source_map = Rc::new(SourceMap::new(FilePathMapping::empty()));
-        let can_reset_errors = Rc::new(RefCell::new(false));
+        let source_map = Lrc::new(SourceMap::new(FilePathMapping::empty()));
+        let can_reset_errors = Lrc::new(AtomicBool::new(false));
 
         let handler = default_handler(
-            Rc::clone(&source_map),
-            Rc::clone(&ignore_path_set),
-            Rc::clone(&can_reset_errors),
+            Lrc::clone(&source_map),
+            Lrc::clone(&ignore_path_set),
+            Lrc::clone(&can_reset_errors),
             config.hide_parse_errors(),
         );
         let parse_sess = RawParseSess::with_span_handler(handler, source_map);
@@ -204,11 +203,11 @@ impl ParseSess {
         SnippetProvider::new(
             source_file.start_pos,
             source_file.end_pos,
-            Rc::clone(source_file.src.as_ref().unwrap()),
+            Lrc::clone(source_file.src.as_ref().unwrap()),
         )
     }
 
-    pub(crate) fn get_original_snippet(&self, file_name: &FileName) -> Option<Rc<String>> {
+    pub(crate) fn get_original_snippet(&self, file_name: &FileName) -> Option<Lrc<String>> {
         self.parse_sess
             .source_map()
             .get_source_file(&file_name.into())
@@ -236,7 +235,7 @@ impl ParseSess {
     }
 
     pub(super) fn can_reset_errors(&self) -> bool {
-        *self.can_reset_errors.borrow()
+        self.can_reset_errors.load(Ordering::Acquire)
     }
 
     pub(super) fn has_errors(&self) -> bool {
@@ -287,9 +286,10 @@ mod tests {
         use crate::utils::mk_sp;
         use rustc_span::{FileName as SourceMapFileName, MultiSpan, RealFileName, DUMMY_SP};
         use std::path::PathBuf;
+        use std::sync::atomic::AtomicU32;
 
         struct TestEmitter {
-            num_emitted_errors: Rc<RefCell<u32>>,
+            num_emitted_errors: Lrc<AtomicU32>,
         }
 
         impl Emitter for TestEmitter {
@@ -297,7 +297,7 @@ mod tests {
                 None
             }
             fn emit_diagnostic(&mut self, _db: &Diagnostic) {
-                *self.num_emitted_errors.borrow_mut() += 1;
+                self.num_emitted_errors.fetch_add(1, Ordering::Release);
             }
         }
 
@@ -314,16 +314,17 @@ mod tests {
         }
 
         fn build_emitter(
-            num_emitted_errors: Rc<RefCell<u32>>,
-            can_reset: Rc<RefCell<bool>>,
-            source_map: Option<Rc<SourceMap>>,
+            num_emitted_errors: Lrc<AtomicU32>,
+            can_reset: Lrc<AtomicBool>,
+            source_map: Option<Lrc<SourceMap>>,
             ignore_list: Option<IgnoreList>,
         ) -> SilentOnIgnoredFilesEmitter {
             let emitter_writer = TestEmitter { num_emitted_errors };
             let source_map =
-                source_map.unwrap_or_else(|| Rc::new(SourceMap::new(FilePathMapping::empty())));
-            let ignore_path_set =
-                Rc::new(IgnorePathSet::from_ignore_list(&ignore_list.unwrap_or_default()).unwrap());
+                source_map.unwrap_or_else(|| Lrc::new(SourceMap::new(FilePathMapping::empty())));
+            let ignore_path_set = Lrc::new(
+                IgnorePathSet::from_ignore_list(&ignore_list.unwrap_or_default()).unwrap(),
+            );
             SilentOnIgnoredFilesEmitter {
                 has_non_ignorable_parser_errors: false,
                 source_map,
@@ -339,10 +340,10 @@ mod tests {
 
         #[test]
         fn handles_fatal_parse_error_in_ignored_file() {
-            let num_emitted_errors = Rc::new(RefCell::new(0));
-            let can_reset_errors = Rc::new(RefCell::new(false));
+            let num_emitted_errors = Lrc::new(AtomicU32::new(0));
+            let can_reset_errors = Lrc::new(AtomicBool::new(false));
             let ignore_list = get_ignore_list(r#"ignore = ["foo.rs"]"#);
-            let source_map = Rc::new(SourceMap::new(FilePathMapping::empty()));
+            let source_map = Lrc::new(SourceMap::new(FilePathMapping::empty()));
             let source =
                 String::from(r#"extern "system" fn jni_symbol!( funcName ) ( ... ) -> {} "#);
             source_map.new_source_file(
@@ -350,16 +351,16 @@ mod tests {
                 source,
             );
             let mut emitter = build_emitter(
-                Rc::clone(&num_emitted_errors),
-                Rc::clone(&can_reset_errors),
-                Some(Rc::clone(&source_map)),
+                Lrc::clone(&num_emitted_errors),
+                Lrc::clone(&can_reset_errors),
+                Some(Lrc::clone(&source_map)),
                 Some(ignore_list),
             );
             let span = MultiSpan::from_span(mk_sp(BytePos(0), BytePos(1)));
             let fatal_diagnostic = build_diagnostic(DiagnosticLevel::Fatal, Some(span));
             emitter.emit_diagnostic(&fatal_diagnostic);
-            assert_eq!(*num_emitted_errors.borrow(), 1);
-            assert_eq!(*can_reset_errors.borrow(), false);
+            assert_eq!(num_emitted_errors.load(Ordering::Acquire), 1);
+            assert_eq!(can_reset_errors.load(Ordering::Acquire), false);
         }
 
         #[test]
@@ -367,26 +368,26 @@ mod tests {
             if !is_nightly_channel!() {
                 return;
             }
-            let num_emitted_errors = Rc::new(RefCell::new(0));
-            let can_reset_errors = Rc::new(RefCell::new(false));
+            let num_emitted_errors = Lrc::new(AtomicU32::new(0));
+            let can_reset_errors = Lrc::new(AtomicBool::new(false));
             let ignore_list = get_ignore_list(r#"ignore = ["foo.rs"]"#);
-            let source_map = Rc::new(SourceMap::new(FilePathMapping::empty()));
+            let source_map = Lrc::new(SourceMap::new(FilePathMapping::empty()));
             let source = String::from(r#"pub fn bar() { 1x; }"#);
             source_map.new_source_file(
                 SourceMapFileName::Real(RealFileName::Named(PathBuf::from("foo.rs"))),
                 source,
             );
             let mut emitter = build_emitter(
-                Rc::clone(&num_emitted_errors),
-                Rc::clone(&can_reset_errors),
-                Some(Rc::clone(&source_map)),
+                Lrc::clone(&num_emitted_errors),
+                Lrc::clone(&can_reset_errors),
+                Some(Lrc::clone(&source_map)),
                 Some(ignore_list),
             );
             let span = MultiSpan::from_span(mk_sp(BytePos(0), BytePos(1)));
             let non_fatal_diagnostic = build_diagnostic(DiagnosticLevel::Warning, Some(span));
             emitter.emit_diagnostic(&non_fatal_diagnostic);
-            assert_eq!(*num_emitted_errors.borrow(), 0);
-            assert_eq!(*can_reset_errors.borrow(), true);
+            assert_eq!(num_emitted_errors.load(Ordering::Acquire), 0);
+            assert_eq!(can_reset_errors.load(Ordering::Acquire), true);
         }
 
         #[test]
@@ -394,25 +395,25 @@ mod tests {
             if !is_nightly_channel!() {
                 return;
             }
-            let num_emitted_errors = Rc::new(RefCell::new(0));
-            let can_reset_errors = Rc::new(RefCell::new(false));
-            let source_map = Rc::new(SourceMap::new(FilePathMapping::empty()));
+            let num_emitted_errors = Lrc::new(AtomicU32::new(0));
+            let can_reset_errors = Lrc::new(AtomicBool::new(false));
+            let source_map = Lrc::new(SourceMap::new(FilePathMapping::empty()));
             let source = String::from(r#"pub fn bar() { 1x; }"#);
             source_map.new_source_file(
                 SourceMapFileName::Real(RealFileName::Named(PathBuf::from("foo.rs"))),
                 source,
             );
             let mut emitter = build_emitter(
-                Rc::clone(&num_emitted_errors),
-                Rc::clone(&can_reset_errors),
-                Some(Rc::clone(&source_map)),
+                Lrc::clone(&num_emitted_errors),
+                Lrc::clone(&can_reset_errors),
+                Some(Lrc::clone(&source_map)),
                 None,
             );
             let span = MultiSpan::from_span(mk_sp(BytePos(0), BytePos(1)));
             let non_fatal_diagnostic = build_diagnostic(DiagnosticLevel::Warning, Some(span));
             emitter.emit_diagnostic(&non_fatal_diagnostic);
-            assert_eq!(*num_emitted_errors.borrow(), 1);
-            assert_eq!(*can_reset_errors.borrow(), false);
+            assert_eq!(num_emitted_errors.load(Ordering::Acquire), 1);
+            assert_eq!(can_reset_errors.load(Ordering::Acquire), false);
         }
 
         #[test]
@@ -420,9 +421,9 @@ mod tests {
             if !is_nightly_channel!() {
                 return;
             }
-            let num_emitted_errors = Rc::new(RefCell::new(0));
-            let can_reset_errors = Rc::new(RefCell::new(false));
-            let source_map = Rc::new(SourceMap::new(FilePathMapping::empty()));
+            let num_emitted_errors = Lrc::new(AtomicU32::new(0));
+            let can_reset_errors = Lrc::new(AtomicBool::new(false));
+            let source_map = Lrc::new(SourceMap::new(FilePathMapping::empty()));
             let ignore_list = get_ignore_list(r#"ignore = ["foo.rs"]"#);
             let bar_source = String::from(r#"pub fn bar() { 1x; }"#);
             let foo_source = String::from(r#"pub fn foo() { 1x; }"#);
@@ -441,9 +442,9 @@ mod tests {
                 fatal_source,
             );
             let mut emitter = build_emitter(
-                Rc::clone(&num_emitted_errors),
-                Rc::clone(&can_reset_errors),
-                Some(Rc::clone(&source_map)),
+                Lrc::clone(&num_emitted_errors),
+                Lrc::clone(&can_reset_errors),
+                Some(Lrc::clone(&source_map)),
                 Some(ignore_list),
             );
             let bar_span = MultiSpan::from_span(mk_sp(BytePos(0), BytePos(1)));
@@ -454,8 +455,8 @@ mod tests {
             emitter.emit_diagnostic(&bar_diagnostic);
             emitter.emit_diagnostic(&foo_diagnostic);
             emitter.emit_diagnostic(&fatal_diagnostic);
-            assert_eq!(*num_emitted_errors.borrow(), 2);
-            assert_eq!(*can_reset_errors.borrow(), false);
+            assert_eq!(num_emitted_errors.load(Ordering::Acquire), 2);
+            assert_eq!(can_reset_errors.load(Ordering::Acquire), false);
         }
     }
 }
diff --git a/src/visitor.rs b/src/visitor.rs
index 55cc9ec7f58..079568630cf 100644
--- a/src/visitor.rs
+++ b/src/visitor.rs
@@ -2,6 +2,7 @@ use std::cell::{Cell, RefCell};
 use std::rc::Rc;
 
 use rustc_ast::{ast, token::DelimToken, visit, AstLike};
+use rustc_data_structures::sync::Lrc;
 use rustc_span::{symbol, BytePos, Pos, Span, DUMMY_SP};
 
 use crate::attr::*;
@@ -32,7 +33,7 @@ use crate::{ErrorKind, FormatReport, FormattingError};
 /// Creates a string slice corresponding to the specified span.
 pub(crate) struct SnippetProvider {
     /// A pointer to the content of the file we are formatting.
-    big_snippet: Rc<String>,
+    big_snippet: Lrc<String>,
     /// A position of the start of `big_snippet`, used as an offset.
     start_pos: usize,
     /// A end position of the file that this snippet lives.
@@ -46,7 +47,7 @@ impl SnippetProvider {
         Some(&self.big_snippet[start_index..end_index])
     }
 
-    pub(crate) fn new(start_pos: BytePos, end_pos: BytePos, big_snippet: Rc<String>) -> Self {
+    pub(crate) fn new(start_pos: BytePos, end_pos: BytePos, big_snippet: Lrc<String>) -> Self {
         let start_pos = start_pos.to_usize();
         let end_pos = end_pos.to_usize();
         SnippetProvider {