Downgrade tracing and syn

There's currently a deadlock with tracing when RUSTC_LOG is enabled.
Downgrade tracing-core for now to avoid blocking the other updates.

syns upgrades cause some nontrivial changes in the diagnostics derive tests,
which are best dealt with in another PR.

Author: Noratrieb

Cargo.lock

@@ -226,7 +226,7 @@ dependencies = [
  "proc-macro2",
  "quote",
  "serde",
- "syn 2.0.22",
+ "syn 2.0.8",
 ]
 
 [[package]]
@@ -450,7 +450,7 @@ checksum = "ff5053a8a42dbff5279a82423946fc56dc1253b76cf211b2b3c14b3aad4e1281"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.22",
+ "syn 2.0.8",
  "synstructure 0.13.0",
 ]
 
@@ -552,7 +552,7 @@ dependencies = [
  "heck",
  "proc-macro2",
  "quote",
- "syn 2.0.22",
+ "syn 2.0.8",
 ]
 
 [[package]]
@@ -630,7 +630,7 @@ dependencies = [
  "quote",
  "regex",
  "serde",
- "syn 2.0.22",
+ "syn 2.0.8",
  "tokio",
 ]
 
@@ -881,7 +881,7 @@ version = "0.1.72"
 dependencies = [
  "itertools",
  "quote",
- "syn 2.0.22",
+ "syn 2.0.8",
 ]
 
 [[package]]
@@ -982,7 +982,7 @@ checksum = "487585f4d0c6655fe74905e2504d8ad6908e4db67f744eb140876906c2f3175d"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.22",
+ "syn 2.0.8",
 ]
 
 [[package]]
@@ -1324,7 +1324,7 @@ checksum = "89ca545a94061b6365f2c7355b4b32bd20df3ff95f02da9329b34ccc3bd6ee72"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.22",
+ "syn 2.0.8",
 ]
 
 [[package]]
@@ -2479,7 +2479,7 @@ dependencies = [
  "pest_meta",
  "proc-macro2",
  "quote",
- "syn 2.0.22",
+ "syn 2.0.8",
 ]
 
 [[package]]
@@ -3393,7 +3393,7 @@ dependencies = [
  "fluent-syntax",
  "proc-macro2",
  "quote",
- "syn 2.0.22",
+ "syn 2.0.8",
  "unic-langid",
 ]
 
@@ -3662,7 +3662,7 @@ version = "0.1.0"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.22",
+ "syn 2.0.8",
  "synstructure 0.13.0",
 ]
 
@@ -4271,7 +4271,7 @@ dependencies = [
  "proc-macro2",
  "quote",
  "serde",
- "syn 2.0.22",
+ "syn 2.0.8",
 ]
 
 [[package]]
@@ -4415,7 +4415,7 @@ checksum = "d9735b638ccc51c28bf6914d90a2e9725b377144fc612c49a611fddd1b631d68"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.22",
+ "syn 2.0.8",
 ]
 
 [[package]]
@@ -4684,9 +4684,9 @@ dependencies = [
 
 [[package]]
 name = "syn"
-version = "2.0.22"
+version = "2.0.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2efbeae7acf4eabd6bcdcbd11c92f45231ddda7539edc7806bd1a04a03b24616"
+checksum = "bcc02725fd69ab9f26eab07fad303e2497fad6fb9eba4f96c4d1687bdf704ad9"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -4713,7 +4713,7 @@ checksum = "285ba80e733fac80aa4270fbcdf83772a79b80aa35c97075320abfee4a915b06"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.22",
+ "syn 2.0.8",
  "unicode-xid",
 ]
 
@@ -4849,7 +4849,7 @@ checksum = "f9456a42c5b0d803c8cd86e73dd7cc9edd429499f37a3550d286d5e86720569f"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.22",
+ "syn 2.0.8",
 ]
 
 [[package]]
@@ -5008,14 +5008,14 @@ checksum = "5f4f31f56159e98206da9efd823404b79b6ef3143b4a7ab76e67b1751b25a4ab"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.22",
+ "syn 2.0.8",
 ]
 
 [[package]]
 name = "tracing-core"
-version = "0.1.31"
+version = "0.1.30"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0955b8137a1df6f1a2e9a37d8a6656291ff0297c1a97c24e0d8425fe2312f79a"
+checksum = "24eb03ba0eab1fd845050058ce5e616558e8f8d8fca633e6b163fe25c797213a"
 dependencies = [
  "once_cell",
  "valuable",
@@ -5424,7 +5424,7 @@ dependencies = [
  "once_cell",
  "proc-macro2",
  "quote",
- "syn 2.0.22",
+ "syn 2.0.8",
  "wasm-bindgen-shared",
 ]
 
@@ -5446,7 +5446,7 @@ checksum = "54681b18a46765f095758388f2d0cf16eb8d4169b639ab575a8f5693af210c7b"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.22",
+ "syn 2.0.8",
  "wasm-bindgen-backend",
  "wasm-bindgen-shared",
 ]

compiler/rustc_log/Cargo.toml

@@ -7,7 +7,7 @@ edition = "2021"
 tracing = "0.1.28"
 tracing-subscriber = { version = "0.3.3", default-features = false, features = ["fmt", "env-filter", "smallvec", "parking_lot", "ansi"] }
 tracing-tree = "0.2.0"
-tracing-core = "0.1.28"
+tracing-core = "=0.1.30" # FIXME(Nilstrieb) tracing has a deadlock: https://github.com/tokio-rs/tracing/issues/2635
 
 [dev-dependencies]
 rustc_span = { path = "../rustc_span" }

compiler/rustc_macros/Cargo.toml

@@ -8,6 +8,7 @@ proc-macro = true
 
 [dependencies]
 synstructure = "0.13.0"
-syn = { version = "2", features = ["full"] }
+# FIXME(Nilstrieb): Updating this causes changes in the diagnostics output.
+syn = { version = "=2.0.8", features = ["full"] }
 proc-macro2 = "1"
 quote = "1"