[INFO] crate tokio-signal 0.3.0-alpha.1 is already in cache
[INFO] testing tokio-signal-0.3.0-alpha.1 against beta-2019-09-28 for beta-1.39-1
[INFO] extracting crate tokio-signal 0.3.0-alpha.1 into work/builds/worker-8/source
[INFO] validating manifest of crates.io crate tokio-signal 0.3.0-alpha.1 on toolchain beta-2019-09-28
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+beta-2019-09-28" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking crates.io crate tokio-signal 0.3.0-alpha.1
[INFO] finished tweaking crates.io crate tokio-signal 0.3.0-alpha.1
[INFO] tweaked toml for crates.io crate tokio-signal 0.3.0-alpha.1 written to work/builds/worker-8/source/Cargo.toml
[INFO] crate crates.io crate tokio-signal 0.3.0-alpha.1 already has a lockfile, it will not be regenerated
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+beta-2019-09-28" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/big/crater/work/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/big/crater/work/builds/worker-8/source:/opt/rustwide/workdir:ro,Z" "-v" "/big/crater/work/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/big/crater/work/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "MAP_USER_ID=1000" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2019-09-28" "build" "--frozen"`
[INFO] [stdout] 595ea32edfa2958a113de4294c4b976cb60da812ee6cb699a3806a09eac81bf8
[INFO] running `"docker" "start" "-a" "595ea32edfa2958a113de4294c4b976cb60da812ee6cb699a3806a09eac81bf8"`
[INFO] [stderr]    Compiling futures-core-preview v0.3.0-alpha.17
[INFO] [stderr]    Compiling arc-swap v0.4.1
[INFO] [stderr]    Compiling tokio-executor v0.2.0-alpha.1
[INFO] [stderr]    Compiling iovec v0.1.2
[INFO] [stderr]    Compiling net2 v0.2.33
[INFO] [stderr]    Compiling parking_lot_core v0.6.2
[INFO] [stderr]    Compiling bytes v0.4.12
[INFO] [stderr]    Compiling futures-sink-preview v0.3.0-alpha.17
[INFO] [stderr]    Compiling futures-util-preview v0.3.0-alpha.17
[INFO] [stderr]    Compiling signal-hook-registry v1.1.1
[INFO] [stderr]    Compiling mio v0.6.19
[INFO] [stderr]    Compiling parking_lot v0.9.0
[INFO] [stderr]    Compiling tokio-io v0.2.0-alpha.1
[INFO] [stderr]    Compiling mio-uds v0.6.7
[INFO] [stderr]    Compiling tokio-sync v0.2.0-alpha.1
[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] 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] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "595ea32edfa2958a113de4294c4b976cb60da812ee6cb699a3806a09eac81bf8"`
[INFO] running `"docker" "rm" "-f" "595ea32edfa2958a113de4294c4b976cb60da812ee6cb699a3806a09eac81bf8"`
[INFO] [stdout] 595ea32edfa2958a113de4294c4b976cb60da812ee6cb699a3806a09eac81bf8