[INFO] fetching crate error-chain-utils-macros 0.1.0...
[INFO] documenting error-chain-utils-macros-0.1.0 against 1.61.0 for beta-1.62-rustdoc-1
[INFO] extracting crate error-chain-utils-macros 0.1.0 into /workspace/builds/worker-109/source
[INFO] validating manifest of crates.io crate error-chain-utils-macros 0.1.0 on toolchain 1.61.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate error-chain-utils-macros 0.1.0
[INFO] finished tweaking crates.io crate error-chain-utils-macros 0.1.0
[INFO] tweaked toml for crates.io crate error-chain-utils-macros 0.1.0 written to /workspace/builds/worker-109/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-109/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-109/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:d190cb871061d98bc6d0581d85cb2ecb09a0f8a142ba5463de30be9999fc3251" "/opt/rustwide/cargo-home/bin/cargo" "+1.61.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 99fcf992834e36378ae303467a43cc92d48219e7330bb47ae0458ea4a2f07671
[INFO] running `Command { std: "docker" "start" "-a" "99fcf992834e36378ae303467a43cc92d48219e7330bb47ae0458ea4a2f07671", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "99fcf992834e36378ae303467a43cc92d48219e7330bb47ae0458ea4a2f07671", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "99fcf992834e36378ae303467a43cc92d48219e7330bb47ae0458ea4a2f07671", kill_on_drop: false }`
[INFO] [stdout] 99fcf992834e36378ae303467a43cc92d48219e7330bb47ae0458ea4a2f07671
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-109/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-109/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" "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:d190cb871061d98bc6d0581d85cb2ecb09a0f8a142ba5463de30be9999fc3251" "/opt/rustwide/cargo-home/bin/cargo" "+1.61.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 634ca862d8ded5eb54d0c754d45b95a1a29ee3c79df7bc306f0bdf1d497ad99b
[INFO] running `Command { std: "docker" "start" "-a" "634ca862d8ded5eb54d0c754d45b95a1a29ee3c79df7bc306f0bdf1d497ad99b", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.39
[INFO] [stderr]     Checking unicode-ident v1.0.0
[INFO] [stderr]    Compiling syn v1.0.95
[INFO] [stderr]     Checking quote v1.0.18
[INFO] [stderr]  Documenting error-chain-utils-macros v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![feature(try_blocks)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:5:1
[INFO] [stdout]   |
[INFO] [stdout] 5 | #![feature(extend_one)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:6:1
[INFO] [stdout]   |
[INFO] [stdout] 6 | #![feature(bool_to_option)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 4 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not document `error-chain-utils-macros`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name error_chain_utils_lib src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=ff6cae619906f295 -L dependency=/opt/rustwide/target/debug/deps --extern proc_macro2=/opt/rustwide/target/debug/deps/libproc_macro2-c1d3bfa6658bd3cb.rmeta --extern quote=/opt/rustwide/target/debug/deps/libquote-5e860005d80c271d.rmeta --extern syn=/opt/rustwide/target/debug/deps/libsyn-e10b46b30f50a15a.rmeta --cap-lints=warn --crate-version 0.1.0` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "634ca862d8ded5eb54d0c754d45b95a1a29ee3c79df7bc306f0bdf1d497ad99b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "634ca862d8ded5eb54d0c754d45b95a1a29ee3c79df7bc306f0bdf1d497ad99b", kill_on_drop: false }`
[INFO] [stdout] 634ca862d8ded5eb54d0c754d45b95a1a29ee3c79df7bc306f0bdf1d497ad99b