[INFO] crate ws_stream 0.0.0 is already in cache
[INFO] testing ws_stream-0.0.0 against beta-2019-09-28 for beta-1.39-1
[INFO] extracting crate ws_stream 0.0.0 into work/builds/worker-6/source
[INFO] validating manifest of crates.io crate ws_stream 0.0.0 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 ws_stream 0.0.0
[INFO] finished tweaking crates.io crate ws_stream 0.0.0
[INFO] tweaked toml for crates.io crate ws_stream 0.0.0 written to work/builds/worker-6/source/Cargo.toml
[INFO] crate crates.io crate ws_stream 0.0.0 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] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"docker" "create" "-v" "/big/crater/work/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/big/crater/work/builds/worker-6/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] c8ac706bd05e6884338103b16f7b7634abf756eac30ce64a8a19b1a832438df5
[INFO] running `"docker" "start" "-a" "c8ac706bd05e6884338103b16f7b7634abf756eac30ce64a8a19b1a832438df5"`
[INFO] [stderr]    Compiling futures-core-preview v0.3.0-alpha.17
[INFO] [stderr]    Compiling futures-io-preview v0.3.0-alpha.17
[INFO] [stderr]    Compiling bytes v0.4.12
[INFO] [stderr]    Compiling openssl-sys v0.9.47
[INFO] [stderr]    Compiling mio v0.6.19
[INFO] [stderr]    Compiling tokio-threadpool v0.1.15
[INFO] [stderr]    Compiling sha-1 v0.8.1
[INFO] [stderr]    Compiling failure v0.1.5
[INFO] [stderr]    Compiling futures-sink-preview v0.3.0-alpha.17
[INFO] [stderr]    Compiling futures-channel-preview v0.3.0-alpha.17
[INFO] [stderr]    Compiling tokio-io v0.1.12
[INFO] [stderr]    Compiling http v0.1.17
[INFO] [stderr]    Compiling input_buffer v0.2.0
[INFO] [stderr]    Compiling openssl v0.10.23
[INFO] [stderr]    Compiling mio-uds v0.6.7
[INFO] [stderr]    Compiling tokio-reactor v0.1.9
[INFO] [stderr]    Compiling tokio-codec v0.1.1
[INFO] [stderr]    Compiling futures-util-preview v0.3.0-alpha.17
[INFO] [stderr]    Compiling tokio-fs v0.1.6
[INFO] [stderr]    Compiling tokio-udp v0.1.3
[INFO] [stderr]    Compiling tokio-uds v0.2.5
[INFO] [stderr]    Compiling tokio-tcp v0.1.3
[INFO] [stderr]    Compiling tokio v0.1.22
[INFO] [stderr]    Compiling native-tls v0.2.3
[INFO] [stderr]    Compiling tokio-tls v0.2.1
[INFO] [stderr]    Compiling tungstenite v0.8.1
[INFO] [stderr]    Compiling tokio-dns-unofficial v0.3.1
[INFO] [stderr]    Compiling futures-executor-preview v0.3.0-alpha.17
[INFO] [stderr]    Compiling futures-preview v0.3.0-alpha.17
[INFO] [stderr]    Compiling tokio-tungstenite v0.8.0
[INFO] [stderr]    Compiling ws_stream v0.0.0 (/opt/rustwide/workdir)
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stderr]  --> src/lib.rs:4:1
[INFO] [stderr]   |
[INFO] [stderr] 4 | #![ 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 `ws_stream`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "c8ac706bd05e6884338103b16f7b7634abf756eac30ce64a8a19b1a832438df5"`
[INFO] running `"docker" "rm" "-f" "c8ac706bd05e6884338103b16f7b7634abf756eac30ce64a8a19b1a832438df5"`
[INFO] [stdout] c8ac706bd05e6884338103b16f7b7634abf756eac30ce64a8a19b1a832438df5