[INFO] fetching crate meio-ws 0.22.1...
[INFO] checking meio-ws-0.22.1 against beta for pr-78714
[INFO] extracting crate meio-ws 0.22.1 into /workspace/builds/worker-8/source
[INFO] validating manifest of crates.io crate meio-ws 0.22.1 on toolchain beta
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate meio-ws 0.22.1
[INFO] finished tweaking crates.io crate meio-ws 0.22.1
[INFO] tweaked toml for crates.io crate meio-ws 0.22.1 written to /workspace/builds/worker-8/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "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" "+beta" "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] f9f78ca002df4ecf6dbab7bd9435ecd850b125689215b66b47b377c7c32118d6
[INFO] running `Command { std: "docker" "start" "-a" "f9f78ca002df4ecf6dbab7bd9435ecd850b125689215b66b47b377c7c32118d6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f9f78ca002df4ecf6dbab7bd9435ecd850b125689215b66b47b377c7c32118d6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f9f78ca002df4ecf6dbab7bd9435ecd850b125689215b66b47b377c7c32118d6", kill_on_drop: false }`
[INFO] [stdout] f9f78ca002df4ecf6dbab7bd9435ecd850b125689215b66b47b377c7c32118d6
[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" "RUSTFLAGS=--cap-lints=forbid" "-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" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 66fd622fe355b9562a180983afa9b9b1fb57ea330e189b2a4a4b87e0deb90153
[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" "66fd622fe355b9562a180983afa9b9b1fb57ea330e189b2a4a4b87e0deb90153", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.48
[INFO] [stderr]    Compiling typenum v1.12.0
[INFO] [stderr]     Checking opaque-debug v0.3.0
[INFO] [stderr]     Checking byte-tools v0.3.1
[INFO] [stderr]     Checking cpuid-bool v0.1.2
[INFO] [stderr]     Checking utf-8 v0.7.5
[INFO] [stderr]     Checking opaque-debug v0.2.3
[INFO] [stderr]     Checking remove_dir_all v0.5.3
[INFO] [stderr]     Checking fake-simd v0.1.2
[INFO] [stderr]     Checking quick-error v1.2.3
[INFO] [stderr]     Checking scoped-tls v1.0.0
[INFO] [stderr]     Checking urlencoding v1.1.1
[INFO] [stderr]    Compiling generic-array v0.14.4
[INFO] [stderr]     Checking input_buffer v0.3.1
[INFO] [stderr]     Checking futures-channel v0.3.8
[INFO] [stderr]     Checking headers-core v0.2.0
[INFO] [stderr]     Checking block-padding v0.1.5
[INFO] [stderr]     Checking twoway v0.1.8
[INFO] [stderr]     Checking buf_redux v0.8.4
[INFO] [stderr]     Checking getrandom v0.1.15
[INFO] [stderr]     Checking signal-hook-registry v1.2.2
[INFO] [stderr]     Checking rand_os v0.1.3
[INFO] [stderr]     Checking time v0.1.44
[INFO] [stderr]     Checking anyhow v1.0.34
[INFO] [stderr]     Checking openssl-sys v0.9.58
[INFO] [stderr]     Checking mio-uds v0.6.8
[INFO] [stderr]     Checking rand_core v0.5.1
[INFO] [stderr]     Checking rand v0.6.5
[INFO] [stderr]     Checking rand_chacha v0.2.2
[INFO] [stderr]     Checking openssl v0.10.30
[INFO] [stderr]     Checking rand v0.7.3
[INFO] [stderr]     Checking generic-array v0.12.3
[INFO] [stderr]     Checking tempfile v3.1.0
[INFO] [stderr]     Checking uuid v0.8.1
[INFO] [stderr]     Checking block-buffer v0.7.3
[INFO] [stderr]     Checking digest v0.8.1
[INFO] [stderr]     Checking multipart v0.17.0
[INFO] [stderr]     Checking sha-1 v0.8.2
[INFO] [stderr]     Checking digest v0.9.0
[INFO] [stderr]     Checking block-buffer v0.9.0
[INFO] [stderr]     Checking headers v0.3.2
[INFO] [stderr]     Checking sha-1 v0.9.2
[INFO] [stderr]     Checking native-tls v0.2.6
[INFO] [stderr]     Checking tungstenite v0.11.1
[INFO] [stderr]    Compiling pin-project-internal v1.0.1
[INFO] [stderr]    Compiling futures-macro v0.3.8
[INFO] [stderr]    Compiling tokio-macros v0.2.6
[INFO] [stderr]    Compiling pin-project-internal v0.4.27
[INFO] [stderr]    Compiling derive_more v0.99.11
[INFO] [stderr]    Compiling async-trait v0.1.41
[INFO] [stderr]     Checking tokio v0.2.23
[INFO] [stderr]     Checking pin-project v1.0.1
[INFO] [stderr]     Checking futures-util v0.3.8
[INFO] [stderr]     Checking pin-project v0.4.27
[INFO] [stderr]     Checking tracing-futures v0.2.4
[INFO] [stderr]     Checking tokio-util v0.3.1
[INFO] [stderr]     Checking futures-executor v0.3.8
[INFO] [stderr]     Checking h2 v0.2.7
[INFO] [stderr]     Checking tokio-tungstenite v0.11.0
[INFO] [stderr]     Checking async-tungstenite v0.9.3
[INFO] [stderr]     Checking futures v0.3.8
[INFO] [stderr]     Checking meio v0.22.1
[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/meio-0.22.1/src/lib.rs:13:1
[INFO] [stdout]    |
[INFO] [stdout] 13 | #![feature(generators)]
[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 `meio`
[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" "66fd622fe355b9562a180983afa9b9b1fb57ea330e189b2a4a4b87e0deb90153", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "66fd622fe355b9562a180983afa9b9b1fb57ea330e189b2a4a4b87e0deb90153", kill_on_drop: false }`
[INFO] [stdout] 66fd622fe355b9562a180983afa9b9b1fb57ea330e189b2a4a4b87e0deb90153