[INFO] fetching crate mqtt_5 0.1.1...
[INFO] documenting mqtt_5-0.1.1 against 1.47.0 for beta-1.48-rustdoc-1
[INFO] extracting crate mqtt_5 0.1.1 into /workspace/builds/worker-9/source
[INFO] validating manifest of crates.io crate mqtt_5 0.1.1 on toolchain 1.47.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate mqtt_5 0.1.1
[INFO] finished tweaking crates.io crate mqtt_5 0.1.1
[INFO] tweaked toml for crates.io crate mqtt_5 0.1.1 written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "+1.47.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 946534f24d195ab1213b68f3c5dd19e42382eeeda759713f04c474c00cbd8db4
[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" "946534f24d195ab1213b68f3c5dd19e42382eeeda759713f04c474c00cbd8db4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "946534f24d195ab1213b68f3c5dd19e42382eeeda759713f04c474c00cbd8db4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "946534f24d195ab1213b68f3c5dd19e42382eeeda759713f04c474c00cbd8db4", kill_on_drop: false }`
[INFO] [stdout] 946534f24d195ab1213b68f3c5dd19e42382eeeda759713f04c474c00cbd8db4
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "+1.47.0" "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] f7eaaeb87b8c50411a75f685ee98ead38e1b0b8d5dc82e7f61b65531107b166c
[INFO] running `Command { std: "docker" "start" "-a" "f7eaaeb87b8c50411a75f685ee98ead38e1b0b8d5dc82e7f61b65531107b166c", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.45
[INFO] [stderr]    Compiling log v0.4.11
[INFO] [stderr]     Checking futures-core v0.3.6
[INFO] [stderr]     Checking futures-io v0.3.6
[INFO] [stderr]     Checking fastrand v1.4.0
[INFO] [stderr]     Checking pin-project-lite v0.1.10
[INFO] [stderr]     Checking event-listener v2.5.1
[INFO] [stderr]     Checking vec-arena v1.0.0
[INFO] [stderr]     Checking async-task v4.0.3
[INFO] [stderr]     Checking bit_reverse v0.1.8
[INFO] [stderr]     Checking nb-connect v1.0.2
[INFO] [stderr]     Checking async-mutex v1.4.0
[INFO] [stderr]     Checking async-channel v1.5.1
[INFO] [stderr]     Checking futures-lite v1.11.1
[INFO] [stderr]     Checking polling v2.0.2
[INFO] [stderr]     Checking kv-log-macro v1.0.7
[INFO] [stderr]     Checking async-executor v1.3.0
[INFO] [stderr]     Checking async-io v1.1.10
[INFO] [stderr]     Checking blocking v1.0.2
[INFO] [stderr]     Checking async-global-executor v1.4.0
[INFO] [stderr]    Compiling synstructure v0.12.4
[INFO] [stderr]    Compiling failure_derive v0.1.8
[INFO] [stderr]    Compiling async-attributes v1.1.1
[INFO] [stderr]    Compiling async-trait v0.1.41
[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" "f7eaaeb87b8c50411a75f685ee98ead38e1b0b8d5dc82e7f61b65531107b166c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f7eaaeb87b8c50411a75f685ee98ead38e1b0b8d5dc82e7f61b65531107b166c", kill_on_drop: false }`
[INFO] [stdout] f7eaaeb87b8c50411a75f685ee98ead38e1b0b8d5dc82e7f61b65531107b166c
