[INFO] cloning repository https://github.com/sgeisler/btcbc-rs
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/sgeisler/btcbc-rs" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsgeisler%2Fbtcbc-rs", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsgeisler%2Fbtcbc-rs'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 262a4f3c81d3cd88eae9e9a8ab9ed949742a3f58
[INFO] documenting sgeisler/btcbc-rs against beta-2020-08-29 for beta-1.47-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsgeisler%2Fbtcbc-rs" "/workspace/builds/worker-5/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-5/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/sgeisler/btcbc-rs 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 git repo https://github.com/sgeisler/btcbc-rs
[INFO] finished tweaking git repo https://github.com/sgeisler/btcbc-rs
[INFO] tweaked toml for git repo https://github.com/sgeisler/btcbc-rs written to /workspace/builds/worker-5/source/Cargo.toml
[INFO] crate git repo https://github.com/sgeisler/btcbc-rs 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]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[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" "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] 0861d068c3db2cbc1901d3e16f0d6555ca34eec0494763df45f3b77168641b4e
[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" "0861d068c3db2cbc1901d3e16f0d6555ca34eec0494763df45f3b77168641b4e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0861d068c3db2cbc1901d3e16f0d6555ca34eec0494763df45f3b77168641b4e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0861d068c3db2cbc1901d3e16f0d6555ca34eec0494763df45f3b77168641b4e", kill_on_drop: false }`
[INFO] [stdout] 0861d068c3db2cbc1901d3e16f0d6555ca34eec0494763df45f3b77168641b4e
[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" "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] 3ceab11bc3151f02a511afda972e4b9f8d63c3d8a34ab90204e0541534133131
[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" "3ceab11bc3151f02a511afda972e4b9f8d63c3d8a34ab90204e0541534133131", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.72
[INFO] [stderr]    Compiling syn v1.0.34
[INFO] [stderr]    Compiling serde v1.0.114
[INFO] [stderr]    Compiling indexmap v1.4.0
[INFO] [stderr]    Compiling proc-macro-error-attr v1.0.3
[INFO] [stderr]    Compiling proc-macro-error v1.0.3
[INFO] [stderr]     Checking input_buffer v0.3.1
[INFO] [stderr]    Compiling proc-macro2 v1.0.18
[INFO] [stderr]    Compiling native-tls v0.2.4
[INFO] [stderr]     Checking block-buffer v0.7.3
[INFO] [stderr]     Checking sha-1 v0.8.2
[INFO] [stderr]    Compiling quote v1.0.7
[INFO] [stderr]     Checking net2 v0.2.34
[INFO] [stderr]     Checking iovec v0.1.4
[INFO] [stderr]     Checking signal-hook-registry v1.2.0
[INFO] [stderr]     Checking num_cpus v1.13.0
[INFO] [stderr]     Checking openssl-sys v0.9.58
[INFO] [stderr]     Checking getrandom v0.1.14
[INFO] [stderr]     Checking socket2 v0.3.12
[INFO] [stderr]     Checking time v0.1.43
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking clap v2.33.1
[INFO] [stderr]     Checking rand_core v0.5.1
[INFO] [stderr]     Checking mio v0.6.22
[INFO] [stderr]     Checking rand_chacha v0.2.2
[INFO] [stderr]     Checking rand v0.7.3
[INFO] [stderr]     Checking openssl v0.10.30
[INFO] [stderr]     Checking mio-uds v0.6.8
[INFO] [stderr]     Checking serde_urlencoded v0.6.1
[INFO] [stderr]     Checking tungstenite v0.10.1
[INFO] [stderr]    Compiling syn-mid v0.5.0
[INFO] [stderr]    Compiling pin-project-internal v0.4.22
[INFO] [stderr]    Compiling tokio-macros v0.2.5
[INFO] [stderr]    Compiling futures-macro v0.3.5
[INFO] [stderr]     Checking tokio v0.2.21
[INFO] [stderr]    Compiling structopt-derive v0.4.8
[INFO] [stderr]     Checking pin-project v0.4.22
[INFO] [stderr]     Checking futures-util v0.3.5
[INFO] [stderr]     Checking structopt v0.3.15
[INFO] [stderr]     Checking tokio-util v0.3.1
[INFO] [stderr]     Checking tokio-tls v0.3.1
[INFO] [stderr]     Checking h2 v0.2.6
[INFO] [stderr]     Checking futures-executor v0.3.5
[INFO] [stderr]     Checking futures v0.3.5
[INFO] [stderr]     Checking tokio-tungstenite v0.10.1
[INFO] [stderr]     Checking hyper v0.13.7
[INFO] [stderr]     Checking hyper-tls v0.4.3
[INFO] [stderr]     Checking reqwest v0.10.6
[INFO] [stderr]  Documenting btcbc-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:1:1
[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 `btcbc-rs`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type bin --crate-name btcbc_rs src/main.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi --document-private-items -L dependency=/opt/rustwide/target/debug/deps --extern futures=/opt/rustwide/target/debug/deps/libfutures-176b48c9305607e0.rmeta --extern reqwest=/opt/rustwide/target/debug/deps/libreqwest-5f78b4ee5e6e5ee1.rmeta --extern structopt=/opt/rustwide/target/debug/deps/libstructopt-6194e7d9359e13de.rmeta --extern tokio=/opt/rustwide/target/debug/deps/libtokio-4a313d37408f8e58.rmeta --extern tokio_tungstenite=/opt/rustwide/target/debug/deps/libtokio_tungstenite-741461c2219fa356.rmeta --extern tungstenite=/opt/rustwide/target/debug/deps/libtungstenite-fb72eecf53dcdde4.rmeta --cap-lints=warn --crate-version 0.1.0` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "3ceab11bc3151f02a511afda972e4b9f8d63c3d8a34ab90204e0541534133131", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3ceab11bc3151f02a511afda972e4b9f8d63c3d8a34ab90204e0541534133131", kill_on_drop: false }`
[INFO] [stdout] 3ceab11bc3151f02a511afda972e4b9f8d63c3d8a34ab90204e0541534133131