[INFO] crate awsm 0.0.11 is already in cache
[INFO] testing awsm-0.0.11 against beta-2019-09-28 for beta-1.39-1
[INFO] extracting crate awsm 0.0.11 into work/builds/worker-5/source
[INFO] validating manifest of crates.io crate awsm 0.0.11 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 awsm 0.0.11
[INFO] finished tweaking crates.io crate awsm 0.0.11
[INFO] tweaked toml for crates.io crate awsm 0.0.11 written to work/builds/worker-5/source/Cargo.toml
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+beta-2019-09-28" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[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-5/target:/opt/rustwide/target:rw,Z" "-v" "/big/crater/work/builds/worker-5/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] 4b80200d1e340eb3d2a4a16f825aed5c30968f0ce1e7823e6b60f5758f5dafc5
[INFO] running `"docker" "start" "-a" "4b80200d1e340eb3d2a4a16f825aed5c30968f0ce1e7823e6b60f5758f5dafc5"`
[INFO] [stderr]    Compiling futures-core-preview v0.3.0-alpha.16
[INFO] [stderr]    Compiling beach_map v0.1.2
[INFO] [stderr]    Compiling rand_core v0.3.1
[INFO] [stderr]    Compiling proc-macro-hack v0.5.10
[INFO] [stderr]    Compiling weedle v0.10.0
[INFO] [stderr]    Compiling wasm-bindgen v0.2.51
[INFO] [stderr]    Compiling rand_isaac v0.1.1
[INFO] [stderr]    Compiling rand_hc v0.1.0
[INFO] [stderr]    Compiling rand_xorshift v0.1.1
[INFO] [stderr]    Compiling rand_chacha v0.1.1
[INFO] [stderr]    Compiling futures-channel-preview v0.3.0-alpha.16
[INFO] [stderr]    Compiling futures-io-preview v0.3.0-alpha.16
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]    Compiling futures-sink-preview v0.3.0-alpha.16
[INFO] [stderr]    Compiling js-sys v0.3.28
[INFO] [stderr]    Compiling futures-select-macro-preview v0.3.0-alpha.16
[INFO] [stderr]    Compiling wasm-bindgen-webidl v0.2.51
[INFO] [stderr]    Compiling serde-wasm-bindgen v0.1.3
[INFO] [stderr]    Compiling futures-util-preview v0.3.0-alpha.16
[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/futures-util-preview-0.3.0-alpha.16/src/lib.rs:4:38
[INFO] [stderr]   |
[INFO] [stderr] 4 | #![cfg_attr(feature = "async-await", 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 `futures-util-preview`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "4b80200d1e340eb3d2a4a16f825aed5c30968f0ce1e7823e6b60f5758f5dafc5"`
[INFO] running `"docker" "rm" "-f" "4b80200d1e340eb3d2a4a16f825aed5c30968f0ce1e7823e6b60f5758f5dafc5"`
[INFO] [stdout] 4b80200d1e340eb3d2a4a16f825aed5c30968f0ce1e7823e6b60f5758f5dafc5