[INFO] fetching crate aktoro-runtime 0.1.0-alpha.4...
[INFO] testing aktoro-runtime-0.1.0-alpha.4 against 1.54.0 for beta-1.55-1
[INFO] extracting crate aktoro-runtime 0.1.0-alpha.4 into /workspace/builds/worker-14/source
[INFO] validating manifest of crates.io crate aktoro-runtime 0.1.0-alpha.4 on toolchain 1.54.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate aktoro-runtime 0.1.0-alpha.4
[INFO] finished tweaking crates.io crate aktoro-runtime 0.1.0-alpha.4
[INFO] tweaked toml for crates.io crate aktoro-runtime 0.1.0-alpha.4 written to /workspace/builds/worker-14/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/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" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] df37af725541d240970ff013c49f2273f22aecd3f22a025f0ce2e7b13f6247a1
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "df37af725541d240970ff013c49f2273f22aecd3f22a025f0ce2e7b13f6247a1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "df37af725541d240970ff013c49f2273f22aecd3f22a025f0ce2e7b13f6247a1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "df37af725541d240970ff013c49f2273f22aecd3f22a025f0ce2e7b13f6247a1", kill_on_drop: false }`
[INFO] [stdout] df37af725541d240970ff013c49f2273f22aecd3f22a025f0ce2e7b13f6247a1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/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" "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" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 454ad3c5234c0e007db4012557d5f070358ec41134c29caf93d18e8569578f6e
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "454ad3c5234c0e007db4012557d5f070358ec41134c29caf93d18e8569578f6e", kill_on_drop: false }`
[INFO] [stderr]    Compiling futures-core-preview v0.3.0-alpha.19
[INFO] [stderr]    Compiling proc-macro2 v1.0.28
[INFO] [stderr]    Compiling futures-sink-preview v0.3.0-alpha.19
[INFO] [stderr]    Compiling futures-io-preview v0.3.0-alpha.19
[INFO] [stderr]    Compiling rand_xoshiro v0.2.0
[INFO] [stderr]    Compiling rand_os v0.1.3
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]    Compiling futures-channel-preview v0.3.0-alpha.19
[INFO] [stderr]    Compiling aktoro-channel v0.1.0-alpha.8
[INFO] [stderr]    Compiling aktoro-raw v0.1.0-alpha.4
[INFO] [stderr]    Compiling futures-util-preview v0.3.0-alpha.19
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]    Compiling syn v1.0.74
[INFO] [stderr]    Compiling futures-executor-preview v0.3.0-alpha.19
[INFO] [stderr]    Compiling futures-preview v0.3.0-alpha.19
[INFO] [stderr]    Compiling runtime-raw v0.3.0-alpha.5
[INFO] [stderr]    Compiling pin-project-internal v0.4.28
[INFO] [stderr]    Compiling runtime-attributes v0.3.0-alpha.6
[INFO] [stderr]    Compiling pin-project v0.4.28
[INFO] [stderr]    Compiling runtime v0.3.0-alpha.8
[INFO] [stderr]    Compiling aktoro-runtime v0.1.0-alpha.4 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(async_await)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^ help: remove the attribute
[INFO] [stdout]   |
[INFO] [stdout]   = help: the feature `async_await` has been stable since 1.39.0 and no longer requires an attribute to enable
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `aktoro-runtime`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "454ad3c5234c0e007db4012557d5f070358ec41134c29caf93d18e8569578f6e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "454ad3c5234c0e007db4012557d5f070358ec41134c29caf93d18e8569578f6e", kill_on_drop: false }`
[INFO] [stdout] 454ad3c5234c0e007db4012557d5f070358ec41134c29caf93d18e8569578f6e
