[INFO] fetching crate syn-serde 0.3.1...
[INFO] testing syn-serde-0.3.1 against beta-2025-09-21 for beta-1.91-3
[INFO] extracting crate syn-serde 0.3.1 into /workspace/builds/worker-7-tc2/source
[INFO] started tweaking crates.io crate syn-serde 0.3.1
[INFO] finished tweaking crates.io crate syn-serde 0.3.1
[INFO] tweaked toml for crates.io crate syn-serde 0.3.1 written to /workspace/builds/worker-7-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate syn-serde 0.3.1 on toolchain beta-2025-09-21
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2025-09-21" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2025-09-21" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 11 packages to latest compatible versions
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2025-09-21" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2025-09-21" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] d1f31bcd39a9e9ad5484056cb4fe108acf5b1e3b061137a5690b51722acc713a
[INFO] running `Command { std: "docker" "start" "-a" "d1f31bcd39a9e9ad5484056cb4fe108acf5b1e3b061137a5690b51722acc713a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d1f31bcd39a9e9ad5484056cb4fe108acf5b1e3b061137a5690b51722acc713a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d1f31bcd39a9e9ad5484056cb4fe108acf5b1e3b061137a5690b51722acc713a", kill_on_drop: false }`
[INFO] [stdout] d1f31bcd39a9e9ad5484056cb4fe108acf5b1e3b061137a5690b51722acc713a
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "RUSTDOCFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2025-09-21" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] eb741fd46f51863de6a232eee38d7429690cf38956dde76c6ff87d8df4de3537
[INFO] running `Command { std: "docker" "start" "-a" "eb741fd46f51863de6a232eee38d7429690cf38956dde76c6ff87d8df4de3537", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.101
[INFO] [stderr]    Compiling serde v1.0.228
[INFO] [stderr]    Compiling syn v2.0.106
[INFO] [stderr]    Compiling quote v1.0.41
[INFO] [stderr]    Compiling serde_derive v1.0.228
[INFO] [stderr]    Compiling syn-serde v0.3.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `VisRestricted`
[INFO] [stdout]  --> src/data.rs:7:55
[INFO] [stdout]   |
[INFO] [stdout] 7 |     ast_struct::{FieldsNamed, FieldsUnnamed, Variant, VisRestricted},
[INFO] [stdout]   |                                                       ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `GenericArgument`
[INFO] [stdout]  --> src/expr.rs:6:22
[INFO] [stdout]   |
[INFO] [stdout] 6 |     ast_enum::{Expr, GenericArgument, Member, RangeLimits},
[INFO] [stdout]   |                      ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Variadic`
[INFO] [stdout]   --> src/ty.rs:10:9
[INFO] [stdout]    |
[INFO] [stdout] 10 |         Variadic,
[INFO] [stdout]    |         ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 12.21s
[INFO] running `Command { std: "docker" "inspect" "eb741fd46f51863de6a232eee38d7429690cf38956dde76c6ff87d8df4de3537", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "eb741fd46f51863de6a232eee38d7429690cf38956dde76c6ff87d8df4de3537", kill_on_drop: false }`
[INFO] [stdout] eb741fd46f51863de6a232eee38d7429690cf38956dde76c6ff87d8df4de3537
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "RUSTDOCFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2025-09-21" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 2f2724be51c2ef30db880c9645aff7e29ba938ed274966ace49266fbe4bece27
[INFO] running `Command { std: "docker" "start" "-a" "2f2724be51c2ef30db880c9645aff7e29ba938ed274966ace49266fbe4bece27", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.101
[INFO] [stderr]    Compiling quote v1.0.41
[INFO] [stderr]    Compiling syn v2.0.106
[INFO] [stderr]    Compiling serde_derive v1.0.228
[INFO] [stderr]    Compiling syn-serde v0.3.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `VisRestricted`
[INFO] [stdout]  --> src/data.rs:7:55
[INFO] [stdout]   |
[INFO] [stdout] 7 |     ast_struct::{FieldsNamed, FieldsUnnamed, Variant, VisRestricted},
[INFO] [stdout]   |                                                       ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `GenericArgument`
[INFO] [stdout]  --> src/expr.rs:6:22
[INFO] [stdout]   |
[INFO] [stdout] 6 |     ast_enum::{Expr, GenericArgument, Member, RangeLimits},
[INFO] [stdout]   |                      ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Variadic`
[INFO] [stdout]   --> src/ty.rs:10:9
[INFO] [stdout]    |
[INFO] [stdout] 10 |         Variadic,
[INFO] [stdout]    |         ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `VisRestricted`
[INFO] [stdout]  --> src/data.rs:7:55
[INFO] [stdout]   |
[INFO] [stdout] 7 |     ast_struct::{FieldsNamed, FieldsUnnamed, Variant, VisRestricted},
[INFO] [stdout]   |                                                       ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `GenericArgument`
[INFO] [stdout]  --> src/expr.rs:6:22
[INFO] [stdout]   |
[INFO] [stdout] 6 |     ast_enum::{Expr, GenericArgument, Member, RangeLimits},
[INFO] [stdout]   |                      ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Variadic`
[INFO] [stdout]   --> src/ty.rs:10:9
[INFO] [stdout]    |
[INFO] [stdout] 10 |         Variadic,
[INFO] [stdout]    |         ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0433]: failed to resolve: could not find `json` in `syn_serde`
[INFO] [stdout]    --> tests/test_item.rs:9:47
[INFO] [stdout]     |
[INFO] [stdout]   9 |     println!("actual:\n```\n{}\n", syn_serde::json::to_string_pretty(actual));
[INFO] [stdout]     |                                               ^^^^ could not find `json` in `syn_serde`
[INFO] [stdout]     |
[INFO] [stdout] note: found an item that was configured out
[INFO] [stdout]    --> /opt/rustwide/workdir/src/lib.rs:276:9
[INFO] [stdout]     |
[INFO] [stdout] 274 | #[cfg(feature = "json")]
[INFO] [stdout]     |       ---------------- the item is gated behind the `json` feature
[INFO] [stdout] 275 | #[cfg_attr(docsrs, doc(cfg(feature = "json")))]
[INFO] [stdout] 276 | pub mod json;
[INFO] [stdout]     |         ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0433`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `syn-serde` (test "test_item") due to 1 previous error
[INFO] running `Command { std: "docker" "inspect" "2f2724be51c2ef30db880c9645aff7e29ba938ed274966ace49266fbe4bece27", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2f2724be51c2ef30db880c9645aff7e29ba938ed274966ace49266fbe4bece27", kill_on_drop: false }`
[INFO] [stdout] 2f2724be51c2ef30db880c9645aff7e29ba938ed274966ace49266fbe4bece27