[INFO] fetching crate fb_stats 0.1.2...
[INFO] testing fb_stats-0.1.2 against beta-2021-09-08 for beta-1.56-1
[INFO] extracting crate fb_stats 0.1.2 into /workspace/builds/worker-2/source
[INFO] validating manifest of crates.io crate fb_stats 0.1.2 on toolchain beta-2021-09-08
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate fb_stats 0.1.2
[INFO] finished tweaking crates.io crate fb_stats 0.1.2
[INFO] tweaked toml for crates.io crate fb_stats 0.1.2 written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "fetch" "--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-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 258adc53230ea7fdf6e7d7bae1c37dff16589ec249b5856b32ca1789e9d154c6
[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" "258adc53230ea7fdf6e7d7bae1c37dff16589ec249b5856b32ca1789e9d154c6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "258adc53230ea7fdf6e7d7bae1c37dff16589ec249b5856b32ca1789e9d154c6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "258adc53230ea7fdf6e7d7bae1c37dff16589ec249b5856b32ca1789e9d154c6", kill_on_drop: false }`
[INFO] [stdout] 258adc53230ea7fdf6e7d7bae1c37dff16589ec249b5856b32ca1789e9d154c6
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] bbd8119d37986c487992f5ebce5da898bc1897fd9d4e9bf3c918b3e3c3a8ab28
[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" "bbd8119d37986c487992f5ebce5da898bc1897fd9d4e9bf3c918b3e3c3a8ab28", kill_on_drop: false }`
[INFO] [stderr]    Compiling perthread v0.1.2
[INFO] [stderr]    Compiling bytes v0.4.12
[INFO] [stderr]    Compiling futures-channel v0.3.17
[INFO] [stderr]    Compiling futures-macro v0.3.17
[INFO] [stderr]    Compiling fbinit_macros v0.1.2
[INFO] [stderr]    Compiling tokio-macros v0.2.6
[INFO] [stderr]    Compiling env_logger v0.7.1
[INFO] [stderr]    Compiling proc-macro-error v1.0.4
[INFO] [stderr]    Compiling quickcheck v0.9.2
[INFO] [stderr]    Compiling auto_impl v0.4.1
[INFO] [stderr]    Compiling tokio-io v0.1.13
[INFO] [stderr]    Compiling tokio-reactor v0.1.12
[INFO] [stderr]    Compiling tokio-codec v0.1.2
[INFO] [stderr]    Compiling tokio-fs v0.1.7
[INFO] [stderr]    Compiling fbinit v0.1.2
[INFO] [stderr]    Compiling tokio v0.2.13
[INFO] [stderr]    Compiling tokio-uds v0.2.7
[INFO] [stderr]    Compiling tokio-udp v0.1.6
[INFO] [stderr]    Compiling tokio-tcp v0.1.4
[INFO] [stderr]    Compiling futures-util v0.3.17
[INFO] [stderr]    Compiling tokio v0.1.22
[INFO] [stderr]    Compiling fb_futures_ext v0.1.2
[INFO] [stderr]    Compiling fb_stats_traits v0.1.0
[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/fb_futures_ext-0.1.2/src/lib.rs:11:1
[INFO] [stdout]    |
[INFO] [stdout] 11 | #![feature(never_type)]
[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 `fb_futures_ext` due to 2 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "bbd8119d37986c487992f5ebce5da898bc1897fd9d4e9bf3c918b3e3c3a8ab28", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bbd8119d37986c487992f5ebce5da898bc1897fd9d4e9bf3c918b3e3c3a8ab28", kill_on_drop: false }`
[INFO] [stdout] bbd8119d37986c487992f5ebce5da898bc1897fd9d4e9bf3c918b3e3c3a8ab28