[INFO] cloning repository https://github.com/tomasol/chat-async
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/tomasol/chat-async" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftomasol%2Fchat-async", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftomasol%2Fchat-async'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 3f9964e62e8fd5b0981732e7832e0523269e4b60
[INFO] documenting tomasol/chat-async against 1.61.0 for beta-1.62-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftomasol%2Fchat-async" "/workspace/builds/worker-13/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-13/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/tomasol/chat-async 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] removed /workspace/builds/worker-13/source/rust-toolchain
[INFO] started tweaking git repo https://github.com/tomasol/chat-async
[INFO] finished tweaking git repo https://github.com/tomasol/chat-async
[INFO] tweaked toml for git repo https://github.com/tomasol/chat-async written to /workspace/builds/worker-13/source/Cargo.toml
[INFO] crate git repo https://github.com/tomasol/chat-async already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded streamunordered v0.5.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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] 6c359bc4a9f62a6815f70c250d0d33f8fb3f13e89b3219d3b644a4f17491538f
[INFO] running `Command { std: "docker" "start" "-a" "6c359bc4a9f62a6815f70c250d0d33f8fb3f13e89b3219d3b644a4f17491538f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6c359bc4a9f62a6815f70c250d0d33f8fb3f13e89b3219d3b644a4f17491538f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6c359bc4a9f62a6815f70c250d0d33f8fb3f13e89b3219d3b644a4f17491538f", kill_on_drop: false }`
[INFO] [stdout] 6c359bc4a9f62a6815f70c250d0d33f8fb3f13e89b3219d3b644a4f17491538f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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] e61128312efaf9921279b395f2fb3551865b3a146a2da3e65f0a1f4611b65ed1
[INFO] running `Command { std: "docker" "start" "-a" "e61128312efaf9921279b395f2fb3551865b3a146a2da3e65f0a1f4611b65ed1", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking cfg-if v0.1.10
[INFO] [stderr]    Compiling proc-macro2 v1.0.6
[INFO] [stderr]    Compiling unicode-xid v0.2.0
[INFO] [stderr]     Checking lazy_static v1.4.0
[INFO] [stderr]    Compiling syn v1.0.11
[INFO] [stderr]    Compiling memchr v2.2.1
[INFO] [stderr]    Compiling libc v0.2.66
[INFO] [stderr]    Compiling autocfg v0.1.7
[INFO] [stderr]    Compiling semver-parser v0.7.0
[INFO] [stderr]    Compiling log v0.4.8
[INFO] [stderr]     Checking slab v0.4.2
[INFO] [stderr]     Checking futures-core v0.3.1
[INFO] [stderr]    Compiling proc-macro-nested v0.1.3
[INFO] [stderr]     Checking futures-sink v0.3.1
[INFO] [stderr]     Checking pin-utils v0.1.0-alpha.4
[INFO] [stderr]     Checking futures-io v0.3.1
[INFO] [stderr]     Checking futures-task v0.3.1
[INFO] [stderr]     Checking scopeguard v1.0.0
[INFO] [stderr]     Checking regex-syntax v0.6.12
[INFO] [stderr]     Checking quick-error v1.2.2
[INFO] [stderr]     Checking once_cell v1.2.0
[INFO] [stderr]     Checking termcolor v1.0.5
[INFO] [stderr]     Checking futures-timer v2.0.2
[INFO] [stderr]     Checking pin-project-lite v0.1.1
[INFO] [stderr]     Checking thread_local v0.3.6
[INFO] [stderr]     Checking crossbeam-utils v0.6.6
[INFO] [stderr]     Checking futures-channel v0.3.1
[INFO] [stderr]     Checking humantime v1.3.0
[INFO] [stderr]    Compiling semver v0.9.0
[INFO] [stderr]    Compiling crossbeam-utils v0.7.0
[INFO] [stderr]    Compiling crossbeam-epoch v0.8.0
[INFO] [stderr]    Compiling rustc_version v0.2.3
[INFO] [stderr]     Checking async-task v1.0.0
[INFO] [stderr]     Checking kv-log-macro v1.0.4
[INFO] [stderr]    Compiling memoffset v0.5.3
[INFO] [stderr]     Checking aho-corasick v0.7.6
[INFO] [stderr]    Compiling quote v1.0.2
[INFO] [stderr]     Checking net2 v0.2.33
[INFO] [stderr]     Checking iovec v0.1.4
[INFO] [stderr]     Checking atty v0.2.13
[INFO] [stderr]     Checking num_cpus v1.11.1
[INFO] [stderr]     Checking crossbeam-channel v0.4.0
[INFO] [stderr]     Checking mio v0.6.21
[INFO] [stderr]     Checking crossbeam-deque v0.7.2
[INFO] [stderr]     Checking regex v1.3.1
[INFO] [stderr]     Checking mio-uds v0.6.7
[INFO] [stderr]     Checking env_logger v0.7.1
[INFO] [stderr]    Compiling proc-macro-hack v0.5.11
[INFO] [stderr]    Compiling async-attributes v1.1.1
[INFO] [stderr]    Compiling futures-macro v0.3.1
[INFO] [stderr]     Checking async-std v1.4.0
[INFO] [stderr]     Checking futures-util v0.3.1
[INFO] [stderr]     Checking futures-executor v0.3.1
[INFO] [stderr]     Checking streamunordered v0.5.0
[INFO] [stderr]     Checking futures v0.3.1
[INFO] [stderr]  Documenting chat-async v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/main.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(async_closure)]
[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 `chat-async`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type bin --crate-name chat_async src/main.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=737803a7ecd3a0cf -L dependency=/opt/rustwide/target/debug/deps --extern async_std=/opt/rustwide/target/debug/deps/libasync_std-53f87bd9cecdfe4f.rmeta --extern env_logger=/opt/rustwide/target/debug/deps/libenv_logger-6963cbebb790faf5.rmeta --extern futures=/opt/rustwide/target/debug/deps/libfutures-8a0e4684f4e2b80d.rmeta --extern log=/opt/rustwide/target/debug/deps/liblog-1073ce7813bbc33a.rmeta --extern streamunordered=/opt/rustwide/target/debug/deps/libstreamunordered-5559b16b126bcbc1.rmeta --cap-lints=warn --crate-version 0.1.0` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "e61128312efaf9921279b395f2fb3551865b3a146a2da3e65f0a1f4611b65ed1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e61128312efaf9921279b395f2fb3551865b3a146a2da3e65f0a1f4611b65ed1", kill_on_drop: false }`
[INFO] [stdout] e61128312efaf9921279b395f2fb3551865b3a146a2da3e65f0a1f4611b65ed1