[INFO] fetching crate rqtt 0.1.0...
[INFO] documenting rqtt-0.1.0 against 1.46.0 for beta-1.47-rustdoc-1
[INFO] extracting crate rqtt 0.1.0 into /workspace/builds/worker-8/source
[INFO] validating manifest of crates.io crate rqtt 0.1.0 on toolchain 1.46.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate rqtt 0.1.0
[INFO] finished tweaking crates.io crate rqtt 0.1.0
[INFO] tweaked toml for crates.io crate rqtt 0.1.0 written to /workspace/builds/worker-8/source/Cargo.toml
[INFO] crate crates.io crate rqtt 0.1.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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" "+1.46.0" "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] 5776501e7ea37197cf167ad8b8f2d2c2956c75e32783db9f6e80a957c78590ff
[INFO] running `Command { std: "docker" "start" "-a" "5776501e7ea37197cf167ad8b8f2d2c2956c75e32783db9f6e80a957c78590ff", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5776501e7ea37197cf167ad8b8f2d2c2956c75e32783db9f6e80a957c78590ff", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5776501e7ea37197cf167ad8b8f2d2c2956c75e32783db9f6e80a957c78590ff", kill_on_drop: false }`
[INFO] [stdout] 5776501e7ea37197cf167ad8b8f2d2c2956c75e32783db9f6e80a957c78590ff
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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" "+1.46.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 6ca4dee10022b8f5589f409e83cbde0448efdc7d538e844825f68bbec1b24348
[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" "6ca4dee10022b8f5589f409e83cbde0448efdc7d538e844825f68bbec1b24348", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.13
[INFO] [stderr]    Compiling log v0.4.8
[INFO] [stderr]    Compiling cc v1.0.48
[INFO] [stderr]     Checking regex-syntax v0.6.12
[INFO] [stderr]     Checking once_cell v1.2.0
[INFO] [stderr]     Checking futures-timer v2.0.2
[INFO] [stderr]     Checking futures-io v0.3.1
[INFO] [stderr]     Checking dtoa v0.4.4
[INFO] [stderr]     Checking bit_reverse v0.1.8
[INFO] [stderr]     Checking mime v0.3.14
[INFO] [stderr]     Checking termcolor v1.0.5
[INFO] [stderr]    Compiling indexmap v1.3.0
[INFO] [stderr]    Compiling num-traits v0.2.10
[INFO] [stderr]    Compiling num-integer v0.1.41
[INFO] [stderr]     Checking lock_api v0.3.2
[INFO] [stderr]     Checking tokio-sync v0.1.7
[INFO] [stderr]    Compiling error-chain v0.12.1
[INFO] [stderr]     Checking tokio-executor v0.1.9
[INFO] [stderr]     Checking crossbeam-queue v0.1.2
[INFO] [stderr]     Checking idna v0.1.5
[INFO] [stderr]     Checking num_cpus v1.11.1
[INFO] [stderr]     Checking rand_os v0.1.3
[INFO] [stderr]     Checking atty v0.2.13
[INFO] [stderr]     Checking base64 v0.10.1
[INFO] [stderr]     Checking aho-corasick v0.7.6
[INFO] [stderr]     Checking combine v3.8.1
[INFO] [stderr]     Checking url v2.1.0
[INFO] [stderr]     Checking flate2 v1.0.13
[INFO] [stderr]     Checking async-task v1.1.1
[INFO] [stderr]     Checking bytes v0.4.12
[INFO] [stderr]     Checking futures-cpupool v0.1.8
[INFO] [stderr]    Compiling mime_guess v2.0.1
[INFO] [stderr]     Checking clap v2.33.0
[INFO] [stderr]     Checking tokio-current-thread v0.1.6
[INFO] [stderr]     Checking tokio-timer v0.2.12
[INFO] [stderr]     Checking rand v0.6.5
[INFO] [stderr]    Compiling structopt-derive v0.2.18
[INFO] [stderr]     Checking http v0.1.21
[INFO] [stderr]     Checking string v0.2.1
[INFO] [stderr]     Checking tokio-buf v0.1.1
[INFO] [stderr]     Checking mio v0.6.21
[INFO] [stderr]     Checking tokio-io v0.1.12
[INFO] [stderr]     Checking kv-log-macro v1.0.4
[INFO] [stderr]     Checking want v0.2.0
[INFO] [stderr]     Checking url v1.7.2
[INFO] [stderr]     Checking uuid v0.7.4
[INFO] [stderr]     Checking chrono v0.4.10
[INFO] [stderr]     Checking mio-uds v0.6.7
[INFO] [stderr]    Compiling backtrace-sys v0.1.32
[INFO] [stderr]    Compiling openssl-sys v0.9.53
[INFO] [stderr]     Checking cookie v0.12.0
[INFO] [stderr]     Checking env_proxy v0.3.1
[INFO] [stderr]     Checking regex v1.3.1
[INFO] [stderr]    Compiling openssl v0.10.26
[INFO] [stderr]    Compiling native-tls v0.2.3
[INFO] [stderr]     Checking backtrace v0.3.40
[INFO] [stderr]     Checking structopt v0.2.18
[INFO] [stderr]     Checking h2 v0.1.26
[INFO] [stderr]     Checking http-body v0.1.0
[INFO] [stderr]     Checking publicsuffix v1.5.4
[INFO] [stderr]    Compiling synstructure v0.12.3
[INFO] [stderr]     Checking toml_edit v0.1.5
[INFO] [stderr]    Compiling serde_derive v1.0.104
[INFO] [stderr]    Compiling failure_derive v0.1.6
[INFO] [stderr]    Compiling async-attributes v1.1.1
[INFO] [stderr]    Compiling async-trait v0.1.22
[INFO] [stderr]    Compiling packattack-derive v0.3.1
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/packattack-derive-0.3.1/src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(arbitrary_enum_discriminant)]
[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 compile `packattack-derive`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "6ca4dee10022b8f5589f409e83cbde0448efdc7d538e844825f68bbec1b24348", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6ca4dee10022b8f5589f409e83cbde0448efdc7d538e844825f68bbec1b24348", kill_on_drop: false }`
[INFO] [stdout] 6ca4dee10022b8f5589f409e83cbde0448efdc7d538e844825f68bbec1b24348