[INFO] fetching crate neutron-star-rt 0.2.1...
[INFO] documenting neutron-star-rt-0.2.1 against 1.54.0 for beta-1.55-rustdoc-1
[INFO] extracting crate neutron-star-rt 0.2.1 into /workspace/builds/worker-5/source
[INFO] validating manifest of crates.io crate neutron-star-rt 0.2.1 on toolchain 1.54.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] removed /workspace/builds/worker-5/source/.cargo/config
[INFO] started tweaking crates.io crate neutron-star-rt 0.2.1
[INFO] finished tweaking crates.io crate neutron-star-rt 0.2.1
[INFO] tweaked toml for crates.io crate neutron-star-rt 0.2.1 written to /workspace/builds/worker-5/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 8b37a60e5d761cab6c696bdbd71850fc7e1ab0cb2ca3527c2a908a91b7a258e4
[INFO] running `Command { std: "docker" "start" "-a" "8b37a60e5d761cab6c696bdbd71850fc7e1ab0cb2ca3527c2a908a91b7a258e4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "8b37a60e5d761cab6c696bdbd71850fc7e1ab0cb2ca3527c2a908a91b7a258e4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8b37a60e5d761cab6c696bdbd71850fc7e1ab0cb2ca3527c2a908a91b7a258e4", kill_on_drop: false }`
[INFO] [stdout] 8b37a60e5d761cab6c696bdbd71850fc7e1ab0cb2ca3527c2a908a91b7a258e4
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 5a91b8078bd9a3b937ecf8e0814c7289554e5047c0a0be362031fa9c2bd50d1a
[INFO] running `Command { std: "docker" "start" "-a" "5a91b8078bd9a3b937ecf8e0814c7289554e5047c0a0be362031fa9c2bd50d1a", kill_on_drop: false }`
[INFO] [stderr]    Compiling neutron-star-rt v0.2.1 (/opt/rustwide/workdir)
[INFO] [stderr]  Documenting neutron-star-rt v0.2.1 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(lang_items, start)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 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 `neutron-star-rt`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name neutron_star_rt src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi --document-private-items -L dependency=/opt/rustwide/target/debug/deps --cap-lints=warn --crate-version 0.2.1` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "5a91b8078bd9a3b937ecf8e0814c7289554e5047c0a0be362031fa9c2bd50d1a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5a91b8078bd9a3b937ecf8e0814c7289554e5047c0a0be362031fa9c2bd50d1a", kill_on_drop: false }`
[INFO] [stdout] 5a91b8078bd9a3b937ecf8e0814c7289554e5047c0a0be362031fa9c2bd50d1a
