[INFO] fetching crate runtime-fmt 0.4.1...
[INFO] documenting runtime-fmt-0.4.1 against beta-2020-08-29 for beta-1.47-rustdoc-1
[INFO] extracting crate runtime-fmt 0.4.1 into /workspace/builds/worker-10/source
[INFO] validating manifest of crates.io crate runtime-fmt 0.4.1 on toolchain beta-2020-08-29
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate runtime-fmt 0.4.1
[INFO] finished tweaking crates.io crate runtime-fmt 0.4.1
[INFO] tweaked toml for crates.io crate runtime-fmt 0.4.1 written to /workspace/builds/worker-10/source/Cargo.toml
[INFO] crate crates.io crate runtime-fmt 0.4.1 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded runtime-fmt-derive v0.2.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-08-29" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] d667687b85992a83bf6ccc8fa93645eb7c2bb5ac0d47488f05d987e3eb66add8
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "d667687b85992a83bf6ccc8fa93645eb7c2bb5ac0d47488f05d987e3eb66add8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d667687b85992a83bf6ccc8fa93645eb7c2bb5ac0d47488f05d987e3eb66add8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d667687b85992a83bf6ccc8fa93645eb7c2bb5ac0d47488f05d987e3eb66add8", kill_on_drop: false }`
[INFO] [stdout] d667687b85992a83bf6ccc8fa93645eb7c2bb5ac0d47488f05d987e3eb66add8
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-08-29" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 2736fbf6bf1ee47411df7dd5c8e9e9f5d07b1aad2b7780d2d5932feec76c329f
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "2736fbf6bf1ee47411df7dd5c8e9e9f5d07b1aad2b7780d2d5932feec76c329f", kill_on_drop: false }`
[INFO] [stderr]  Documenting runtime-fmt v0.4.1 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> src/lib.rs:17:1
[INFO] [stdout]    |
[INFO] [stdout] 17 | #![feature(fmt_internals)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> src/lib.rs:18:1
[INFO] [stdout]    |
[INFO] [stdout] 18 | #![feature(unicode_internals)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> src/lib.rs:19:1
[INFO] [stdout]    |
[INFO] [stdout] 19 | #![feature(specialization)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> src/lib.rs:20:1
[INFO] [stdout]    |
[INFO] [stdout] 20 | #![feature(print_internals)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> src/lib.rs:21:1
[INFO] [stdout]    |
[INFO] [stdout] 21 | #![feature(rustc_private)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 6 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 `runtime-fmt`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --crate-type lib --crate-name runtime_fmt 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 --extern unicode_xid=/opt/rustwide/target/debug/deps/libunicode_xid-10b9243c1c69504c.rmeta --cap-lints=warn --crate-version 0.4.1` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "2736fbf6bf1ee47411df7dd5c8e9e9f5d07b1aad2b7780d2d5932feec76c329f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2736fbf6bf1ee47411df7dd5c8e9e9f5d07b1aad2b7780d2d5932feec76c329f", kill_on_drop: false }`
[INFO] [stdout] 2736fbf6bf1ee47411df7dd5c8e9e9f5d07b1aad2b7780d2d5932feec76c329f