[INFO] crate polona-dl 0.1.0 is already in cache
[INFO] checking polona-dl-0.1.0 against beta-2019-10-27 for pr-65897
[INFO] extracting crate polona-dl 0.1.0 into /workspace/builds/worker-0/source
[INFO] validating manifest of crates.io crate polona-dl 0.1.0 on toolchain beta-2019-10-27
[INFO] running `"/workspace/cargo-home/bin/cargo" "+beta-2019-10-27" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking crates.io crate polona-dl 0.1.0
[INFO] finished tweaking crates.io crate polona-dl 0.1.0
[INFO] tweaked toml for crates.io crate polona-dl 0.1.0 written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] crate crates.io crate polona-dl 0.1.0 already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+beta-2019-10-27" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"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" "MAP_USER_ID=0" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=allow" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2019-10-27" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 2d7bd4dc7ef534c373a6a89a70937f2b34e991eaf46e7cb785684c950cc0b007
[INFO] running `"docker" "start" "-a" "2d7bd4dc7ef534c373a6a89a70937f2b34e991eaf46e7cb785684c950cc0b007"`
[INFO] [stderr]     Checking tokio-executor v0.2.0-alpha.1
[INFO] [stderr]    Compiling isahc v0.7.0
[INFO] [stderr]     Checking ci_info v0.3.1
[INFO] [stderr]     Checking lazy_static v1.3.0
[INFO] [stderr]     Checking futures-sink-preview v0.3.0-alpha.17
[INFO] [stderr]    Compiling rstest v0.3.0
[INFO] [stderr]     Checking num-integer v0.1.41
[INFO] [stderr]     Checking number_prefix v0.2.8
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]     Checking tokio-io v0.2.0-alpha.1
[INFO] [stderr]     Checking mio-uds v0.6.7
[INFO] [stderr]     Checking backoff v0.1.5
[INFO] [stderr]     Checking serde v1.0.99
[INFO] [stderr]     Checking crossbeam-utils v0.6.6
[INFO] [stderr]     Checking thread_local v0.3.6
[INFO] [stderr]     Checking clicolors-control v1.0.0
[INFO] [stderr]     Checking c2-chacha v0.2.2
[INFO] [stderr]     Checking tracing-core v0.1.5
[INFO] [stderr]     Checking futures-channel-preview v0.3.0-alpha.17
[INFO] [stderr]     Checking tokio-codec v0.2.0-alpha.1
[INFO] [stderr]     Checking regex v1.2.1
[INFO] [stderr]     Checking num-iter v0.1.39
[INFO] [stderr]     Checking num-rational v0.2.2
[INFO] [stderr]     Checking rand_chacha v0.2.1
[INFO] [stderr]     Checking crossbeam-epoch v0.7.2
[INFO] [stderr]     Checking crossbeam-queue v0.1.2
[INFO] [stderr]     Checking crossbeam-channel v0.3.9
[INFO] [stderr]     Checking tokio-executor v0.1.8
[INFO] [stderr]     Checking futures-util-preview v0.3.0-alpha.17
[INFO] [stderr]     Checking sluice v0.4.1
[INFO] [stderr]     Checking rand v0.7.0
[INFO] [stderr]     Checking tokio-timer v0.2.11
[INFO] [stderr]     Checking crossbeam-deque v0.7.1
[INFO] [stderr]     Checking crossbeam-deque v0.6.3
[INFO] [stderr]     Checking tokio-current-thread v0.2.0-alpha.1
[INFO] [stderr]     Checking rayon-core v1.5.0
[INFO] [stderr]     Checking backoff-futures v0.1.1
[INFO] [stderr]     Checking console v0.7.7
[INFO] [stderr]     Checking rayon v1.1.0
[INFO] [stderr]     Checking better-panic v0.1.2
[INFO] [stderr]     Checking indicatif v0.11.0
[INFO] [stderr]     Checking tempfile v3.1.0
[INFO] [stderr]     Checking tokio-sync v0.2.0-alpha.1
[INFO] [stderr]     Checking futures-executor-preview v0.3.0-alpha.17
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stderr]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/tokio-sync-0.2.0-alpha.1/src/lib.rs:10:1
[INFO] [stderr]    |
[INFO] [stderr] 10 | #![feature(async_await)]
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr]     Checking futures-preview v0.3.0-alpha.17
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr] error: could not compile `tokio-sync`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "2d7bd4dc7ef534c373a6a89a70937f2b34e991eaf46e7cb785684c950cc0b007"`
[INFO] running `"docker" "rm" "-f" "2d7bd4dc7ef534c373a6a89a70937f2b34e991eaf46e7cb785684c950cc0b007"`
[INFO] [stdout] 2d7bd4dc7ef534c373a6a89a70937f2b34e991eaf46e7cb785684c950cc0b007