[INFO] crate harbourmaster 0.3.0 is already in cache
[INFO] testing harbourmaster-0.3.0 against 1.44.0 for beta-1.45-1
[INFO] extracting crate harbourmaster 0.3.0 into /workspace/builds/worker-5/source
[INFO] validating manifest of crates.io crate harbourmaster 0.3.0 on toolchain 1.44.0
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1.44.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking crates.io crate harbourmaster 0.3.0
[INFO] finished tweaking crates.io crate harbourmaster 0.3.0
[INFO] tweaked toml for crates.io crate harbourmaster 0.3.0 written to /workspace/builds/worker-5/source/Cargo.toml
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1.44.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1.44.0" "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-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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=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" "+1.44.0" "build" "--frozen"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] fde14477617f153853791f89e2d7f280048ec0f94fd26d41881ba71a9cc71a32
[INFO] running `"docker" "start" "-a" "fde14477617f153853791f89e2d7f280048ec0f94fd26d41881ba71a9cc71a32"`
[INFO] [stderr] sudo: setrlimit(RLIMIT_CORE): Operation not permitted
[INFO] [stderr]    Compiling hyper-openssl v0.7.1
[INFO] [stderr]    Compiling linked_hash_set v0.1.3
[INFO] [stderr]    Compiling futures-util-preview v0.3.0-alpha.19
[INFO] [stderr]    Compiling parking_lot_core v0.6.2
[INFO] [stderr]    Compiling parking_lot v0.9.0
[INFO] [stderr]    Compiling hyper v0.12.35
[INFO] [stderr]    Compiling tokio-openssl v0.3.0
[INFO] [stderr]    Compiling syn v1.0.30
[INFO] [stderr]    Compiling tokio-reactor v0.1.12
[INFO] [stderr]    Compiling tokio-udp v0.1.6
[INFO] [stderr]    Compiling tokio-tcp v0.1.4
[INFO] [stderr]    Compiling tokio-uds v0.2.6
[INFO] [stderr]    Compiling tokio v0.1.22
[INFO] [stderr]    Compiling futures-executor-preview v0.3.0-alpha.19
[INFO] [stderr]    Compiling serde_derive v1.0.111
[INFO] [stderr]    Compiling futures-preview v0.3.0-alpha.19
[INFO] [stderr]    Compiling hyperlocal v0.6.0
[INFO] [stderr]    Compiling serde v1.0.111
[INFO] [stderr]    Compiling serde_json v1.0.53
[INFO] [stderr]    Compiling shiplift v0.5.0
[INFO] [stderr]    Compiling harbourmaster v0.3.0 (/opt/rustwide/workdir)
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stderr]  --> src/lib.rs:3:1
[INFO] [stderr]   |
[INFO] [stderr] 3 | #![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 `harbourmaster`.
[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 `"docker" "inspect" "fde14477617f153853791f89e2d7f280048ec0f94fd26d41881ba71a9cc71a32"`
[INFO] running `"docker" "rm" "-f" "fde14477617f153853791f89e2d7f280048ec0f94fd26d41881ba71a9cc71a32"`
[INFO] [stdout] fde14477617f153853791f89e2d7f280048ec0f94fd26d41881ba71a9cc71a32