[INFO] cloning repository https://github.com/prajwalprabhu/chatbot-rs
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/prajwalprabhu/chatbot-rs" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fprajwalprabhu%2Fchatbot-rs", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fprajwalprabhu%2Fchatbot-rs'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 721708c3711ddc26972ceb824ce0ca4d47eed2ef
[INFO] documenting prajwalprabhu/chatbot-rs against beta-2022-05-20 for beta-1.62-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fprajwalprabhu%2Fchatbot-rs" "/workspace/builds/worker-7/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/prajwalprabhu/chatbot-rs on toolchain beta-2022-05-20
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2022-05-20" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/prajwalprabhu/chatbot-rs
[INFO] finished tweaking git repo https://github.com/prajwalprabhu/chatbot-rs
[INFO] tweaked toml for git repo https://github.com/prajwalprabhu/chatbot-rs written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] crate git repo https://github.com/prajwalprabhu/chatbot-rs already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2022-05-20" "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/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "+beta-2022-05-20" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 75d00785d31a21aa50fea3703203e1b8be76313e37921d706986e4a1a801be61
[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" "75d00785d31a21aa50fea3703203e1b8be76313e37921d706986e4a1a801be61", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "75d00785d31a21aa50fea3703203e1b8be76313e37921d706986e4a1a801be61", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "75d00785d31a21aa50fea3703203e1b8be76313e37921d706986e4a1a801be61", kill_on_drop: false }`
[INFO] [stdout] 75d00785d31a21aa50fea3703203e1b8be76313e37921d706986e4a1a801be61
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "+beta-2022-05-20" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", 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] 808c6a6518649d77f7237888ea029697eb14c4cfd8f68fdfb39695dca6ee1ad3
[INFO] running `Command { std: "docker" "start" "-a" "808c6a6518649d77f7237888ea029697eb14c4cfd8f68fdfb39695dca6ee1ad3", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.26
[INFO] [stderr]    Compiling serde v1.0.125
[INFO] [stderr]    Compiling syn v1.0.69
[INFO] [stderr]    Compiling serde_json v1.0.64
[INFO] [stderr]    Compiling serde_derive v1.0.125
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]  Documenting chatbot-rs v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/main.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(mutex_unlock)]
[INFO] [stdout]   |            ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not document `chatbot-rs`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type bin --crate-name chatbot_rs src/main.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items '-Arustdoc::private-intra-doc-links' -C metadata=cf32bef303843f21 -L dependency=/opt/rustwide/target/debug/deps --extern serde=/opt/rustwide/target/debug/deps/libserde-2755ae29db2c8411.rmeta --extern serde_derive=/opt/rustwide/target/debug/deps/libserde_derive-b2fbd3cf16ef3c8d.so --extern serde_json=/opt/rustwide/target/debug/deps/libserde_json-e4d9d5a64f9c0bc7.rmeta --cap-lints=warn --crate-version 0.1.0` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "808c6a6518649d77f7237888ea029697eb14c4cfd8f68fdfb39695dca6ee1ad3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "808c6a6518649d77f7237888ea029697eb14c4cfd8f68fdfb39695dca6ee1ad3", kill_on_drop: false }`
[INFO] [stdout] 808c6a6518649d77f7237888ea029697eb14c4cfd8f68fdfb39695dca6ee1ad3