[INFO] fetching crate antlr-rust 0.1.2...
[INFO] documenting antlr-rust-0.1.2 against beta-2020-08-29 for beta-1.47-rustdoc-1
[INFO] extracting crate antlr-rust 0.1.2 into /workspace/builds/worker-6/source
[INFO] validating manifest of crates.io crate antlr-rust 0.1.2 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 antlr-rust 0.1.2
[INFO] finished tweaking crates.io crate antlr-rust 0.1.2
[INFO] tweaked toml for crates.io crate antlr-rust 0.1.2 written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[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 murmur3 v0.4.1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] d85efca079c0667bbc89a7e7a51657cd53c1c4e7ff6617c47c9ebdc2a9d75871
[INFO] running `Command { std: "docker" "start" "-a" "d85efca079c0667bbc89a7e7a51657cd53c1c4e7ff6617c47c9ebdc2a9d75871", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d85efca079c0667bbc89a7e7a51657cd53c1c4e7ff6617c47c9ebdc2a9d75871", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d85efca079c0667bbc89a7e7a51657cd53c1c4e7ff6617c47c9ebdc2a9d75871", kill_on_drop: false }`
[INFO] [stdout] d85efca079c0667bbc89a7e7a51657cd53c1c4e7ff6617c47c9ebdc2a9d75871
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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] eaaf1a21ecc5842883cbd253e715d68254b77981e01727a68509ffa5bc043e55
[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" "eaaf1a21ecc5842883cbd253e715d68254b77981e01727a68509ffa5bc043e55", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking bit-vec v0.6.2
[INFO] [stderr]     Checking typed-arena v2.0.1
[INFO] [stderr]     Checking uuid v0.6.5
[INFO] [stderr]     Checking backtrace v0.3.50
[INFO] [stderr]     Checking murmur3 v0.4.1
[INFO] [stderr]     Checking bit-set v0.5.2
[INFO] [stderr]  Documenting antlr-rust v0.1.2 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(try_blocks)]
[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:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![feature(raw)]
[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:5:1
[INFO] [stdout]   |
[INFO] [stdout] 5 | #![feature(inner_deref)]
[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:6:1
[INFO] [stdout]   |
[INFO] [stdout] 6 | #![feature(is_sorted)]
[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:7:1
[INFO] [stdout]   |
[INFO] [stdout] 7 | #![feature(cell_update)]
[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:8:1
[INFO] [stdout]   |
[INFO] [stdout] 8 | #![feature(get_mut_unchecked)]
[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:9:1
[INFO] [stdout]   |
[INFO] [stdout] 9 | #![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:10:1
[INFO] [stdout]    |
[INFO] [stdout] 10 | #![feature(coerce_unsized)]
[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:11:1
[INFO] [stdout]    |
[INFO] [stdout] 11 | #![feature(unsize)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 10 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 `antlr-rust`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name antlr_rust 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 backtrace=/opt/rustwide/target/debug/deps/libbacktrace-6ae7b45c9f590d92.rmeta --extern bit_set=/opt/rustwide/target/debug/deps/libbit_set-41c3436ce2f1ff15.rmeta --extern byteorder=/opt/rustwide/target/debug/deps/libbyteorder-364c148656283980.rmeta --extern lazy_static=/opt/rustwide/target/debug/deps/liblazy_static-db88f49d9e5662e7.rmeta --extern murmur3=/opt/rustwide/target/debug/deps/libmurmur3-812e3bf4f9d42db9.rmeta --extern once_cell=/opt/rustwide/target/debug/deps/libonce_cell-c30ce74baffcb5b9.rmeta --extern typed_arena=/opt/rustwide/target/debug/deps/libtyped_arena-3848db6f7792cc29.rmeta --extern uuid=/opt/rustwide/target/debug/deps/libuuid-53670f384d4c6ee4.rmeta --cap-lints=warn --crate-version 0.1.2` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "eaaf1a21ecc5842883cbd253e715d68254b77981e01727a68509ffa5bc043e55", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "eaaf1a21ecc5842883cbd253e715d68254b77981e01727a68509ffa5bc043e55", kill_on_drop: false }`
[INFO] [stdout] eaaf1a21ecc5842883cbd253e715d68254b77981e01727a68509ffa5bc043e55