[INFO] fetching crate kf-protocol-fs 3.0.0...
[INFO] testing kf-protocol-fs-3.0.0 against beta-2021-01-01 for beta-1.50-1
[INFO] extracting crate kf-protocol-fs 3.0.0 into /workspace/builds/worker-7/source
[INFO] validating manifest of crates.io crate kf-protocol-fs 3.0.0 on toolchain beta-2021-01-01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate kf-protocol-fs 3.0.0
[INFO] finished tweaking crates.io crate kf-protocol-fs 3.0.0
[INFO] tweaked toml for crates.io crate kf-protocol-fs 3.0.0 written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] crate crates.io crate kf-protocol-fs 3.0.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded tracing v0.1.19
[INFO] [stderr]   Downloaded tracing-core v0.1.16
[INFO] [stderr]   Downloaded tracing-subscriber v0.2.12
[INFO] [stderr]   Downloaded kf-protocol-message v2.0.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 817517f3250051a62d6927274420bbc9754da1aadcc93c9ab1c7ee645d33ee12
[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" "817517f3250051a62d6927274420bbc9754da1aadcc93c9ab1c7ee645d33ee12", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "817517f3250051a62d6927274420bbc9754da1aadcc93c9ab1c7ee645d33ee12", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "817517f3250051a62d6927274420bbc9754da1aadcc93c9ab1c7ee645d33ee12", kill_on_drop: false }`
[INFO] [stdout] 817517f3250051a62d6927274420bbc9754da1aadcc93c9ab1c7ee645d33ee12
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "RUSTFLAGS=--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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c556e112dc7d5041456c137882a525e4efb6001f268110e7c76c721ed49de2f2
[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" "c556e112dc7d5041456c137882a525e4efb6001f268110e7c76c721ed49de2f2", kill_on_drop: false }`
[INFO] [stderr] warning: invalid feature `cli` in required-features of target `file_send`: `cli` is not present in [features] section
[INFO] [stderr]    Compiling syn v1.0.40
[INFO] [stderr]    Compiling fastrand v1.3.5
[INFO] [stderr]    Compiling event-listener v2.4.0
[INFO] [stderr]    Compiling crc32c v0.5.0
[INFO] [stderr]    Compiling vec-arena v0.5.2
[INFO] [stderr]    Compiling send_wrapper v0.4.0
[INFO] [stderr]    Compiling parking v1.0.6
[INFO] [stderr]    Compiling futures-timer v2.0.2
[INFO] [stderr]    Compiling tracing-core v0.1.16
[INFO] [stderr]    Compiling sharded-slab v0.0.9
[INFO] [stderr]    Compiling paste-impl v0.1.18
[INFO] [stderr]    Compiling futures-channel v0.3.5
[INFO] [stderr]    Compiling regex v1.3.9
[INFO] [stderr]    Compiling tokio v0.2.22
[INFO] [stderr]    Compiling time v0.1.44
[INFO] [stderr]    Compiling socket2 v0.3.15
[INFO] [stderr]    Compiling polling v0.1.9
[INFO] [stderr]    Compiling num_cpus v1.13.0
[INFO] [stderr]    Compiling content_inspector v0.2.4
[INFO] [stderr]    Compiling memmap v0.7.0
[INFO] [stderr]    Compiling regex-automata v0.1.9
[INFO] [stderr]    Compiling nix v0.17.0
[INFO] [stderr]    Compiling async-channel v1.4.2
[INFO] [stderr]    Compiling async-mutex v1.3.0
[INFO] [stderr]    Compiling futures-lite v0.1.11
[INFO] [stderr]    Compiling multitask v0.2.0
[INFO] [stderr]    Compiling tracing-log v0.1.1
[INFO] [stderr]    Compiling chrono v0.4.15
[INFO] [stderr]    Compiling num-derive v0.2.5
[INFO] [stderr]    Compiling paste v0.1.18
[INFO] [stderr]    Compiling matchers v0.0.1
[INFO] [stderr]    Compiling async-io v0.1.11
[INFO] [stderr]    Compiling blocking v0.5.2
[INFO] [stderr]    Compiling async-executor v0.1.2
[INFO] [stderr]    Compiling wasm-bindgen-backend v0.2.68
[INFO] [stderr]    Compiling wasm-bindgen-macro-support v0.2.68
[INFO] [stderr]    Compiling serde_derive v1.0.116
[INFO] [stderr]    Compiling tracing-attributes v0.1.11
[INFO] [stderr]    Compiling pin-project-internal v0.4.23
[INFO] [stderr]    Compiling futures-macro v0.3.5
[INFO] [stderr]    Compiling kf-protocol-derive v0.2.0
[INFO] [stderr]    Compiling async-trait v0.1.40
[INFO] [stderr]    Compiling wasm-bindgen-macro v0.2.68
[INFO] [stderr]    Compiling wasm-bindgen v0.2.68
[INFO] [stderr]    Compiling tracing v0.1.19
[INFO] [stderr]    Compiling js-sys v0.3.45
[INFO] [stderr]    Compiling pin-project v0.4.23
[INFO] [stderr]    Compiling futures-util v0.3.5
[INFO] [stderr]    Compiling serde v1.0.116
[INFO] [stderr]    Compiling web-sys v0.3.45
[INFO] [stderr]    Compiling futures-executor v0.3.5
[INFO] [stderr]    Compiling futures v0.3.5
[INFO] [stderr]    Compiling gloo-timers v0.2.1
[INFO] [stderr]    Compiling futures-timer v3.0.2
[INFO] [stderr]    Compiling async-std v1.6.3
[INFO] [stderr]    Compiling tracing-serde v0.1.2
[INFO] [stderr]    Compiling serde_json v1.0.57
[INFO] [stderr]    Compiling 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" "c556e112dc7d5041456c137882a525e4efb6001f268110e7c76c721ed49de2f2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c556e112dc7d5041456c137882a525e4efb6001f268110e7c76c721ed49de2f2", kill_on_drop: false }`
[INFO] [stdout] c556e112dc7d5041456c137882a525e4efb6001f268110e7c76c721ed49de2f2