[INFO] fetching crate kf-protocol 2.0.3...
[INFO] documenting kf-protocol-2.0.3 against beta-2020-08-29 for beta-1.47-rustdoc-1
[INFO] extracting crate kf-protocol 2.0.3 into /workspace/builds/worker-0/source
[INFO] validating manifest of crates.io crate kf-protocol 2.0.3 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 crates.io crate kf-protocol 2.0.3
[INFO] finished tweaking crates.io crate kf-protocol 2.0.3
[INFO] tweaked toml for crates.io crate kf-protocol 2.0.3 written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[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]  Downloading crates ...
[INFO] [stderr]   Downloaded kf-protocol-message v1.0.2
[INFO] [stderr]   Downloaded kf-protocol-fs v2.0.1
[INFO] [stderr]   Downloaded kf-protocol-transport v2.0.3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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] fe6bd27959f95cef99f7a5cb54a18e5e3d67e7fa50652e958ed8f70617aa386a
[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" "fe6bd27959f95cef99f7a5cb54a18e5e3d67e7fa50652e958ed8f70617aa386a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "fe6bd27959f95cef99f7a5cb54a18e5e3d67e7fa50652e958ed8f70617aa386a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fe6bd27959f95cef99f7a5cb54a18e5e3d67e7fa50652e958ed8f70617aa386a", kill_on_drop: false }`
[INFO] [stdout] fe6bd27959f95cef99f7a5cb54a18e5e3d67e7fa50652e958ed8f70617aa386a
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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] 6b6a13b64aeb698f3774d258dfbd02849ea3b4f985f87fbc7061d03b80c088ac
[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" "6b6a13b64aeb698f3774d258dfbd02849ea3b4f985f87fbc7061d03b80c088ac", kill_on_drop: false }`
[INFO] [stderr]    Compiling crc32c v0.5.0
[INFO] [stderr]     Checking send_wrapper v0.4.0
[INFO] [stderr]     Checking futures-timer v2.0.2
[INFO] [stderr]     Checking tokio v0.2.22
[INFO] [stderr]    Compiling log v0.4.11
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking socket2 v0.3.12
[INFO] [stderr]     Checking polling v0.1.7
[INFO] [stderr]     Checking futures-lite v0.1.11
[INFO] [stderr]     Checking content_inspector v0.2.4
[INFO] [stderr]    Compiling num-derive v0.2.5
[INFO] [stderr]     Checking futures-util v0.3.5
[INFO] [stderr]     Checking chrono v0.4.15
[INFO] [stderr]     Checking env_logger v0.7.1
[INFO] [stderr]     Checking env_logger v0.6.2
[INFO] [stderr]    Compiling wasm-bindgen-backend v0.2.67
[INFO] [stderr]    Compiling kf-protocol-derive v0.1.1
[INFO] [stderr]     Checking async-io v0.1.11
[INFO] [stderr]     Checking blocking v0.5.2
[INFO] [stderr]     Checking async-executor v0.1.2
[INFO] [stderr]     Checking tokio-util v0.3.1
[INFO] [stderr]     Checking flv-util v0.2.1
[INFO] [stderr]     Checking flv-util v0.1.1
[INFO] [stderr]    Compiling wasm-bindgen-macro-support v0.2.67
[INFO] [stderr]     Checking kf-protocol-core v0.1.2
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/kf-protocol-core-0.1.2/src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(specialization)]
[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 `kf-protocol-core`.
[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" "6b6a13b64aeb698f3774d258dfbd02849ea3b4f985f87fbc7061d03b80c088ac", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6b6a13b64aeb698f3774d258dfbd02849ea3b4f985f87fbc7061d03b80c088ac", kill_on_drop: false }`
[INFO] [stdout] 6b6a13b64aeb698f3774d258dfbd02849ea3b4f985f87fbc7061d03b80c088ac