[INFO] updating cached repository https://github.com/s-panferov/akta
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune", kill_on_drop: false }`
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 130910202fbf6a8ff7d091314c928cd484d9b215
[INFO] testing s-panferov/akta against beta-2020-07-24 for beta-1.46-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fs-panferov%2Fakta" "/workspace/builds/worker-4/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/s-panferov/akta on toolchain beta-2020-07-24
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-07-24" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/s-panferov/akta
[INFO] finished tweaking git repo https://github.com/s-panferov/akta
[INFO] tweaked toml for git repo https://github.com/s-panferov/akta written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/s-panferov/akta already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-07-24" "fetch" "--locked" "--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-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--network" "none" "rustops/crates-build-env@sha256:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-07-24" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 6b96206e77bf16da8099baf07574449e79ce1eb3e1879e5a0c029ff7658b7950
[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" "6b96206e77bf16da8099baf07574449e79ce1eb3e1879e5a0c029ff7658b7950", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6b96206e77bf16da8099baf07574449e79ce1eb3e1879e5a0c029ff7658b7950", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6b96206e77bf16da8099baf07574449e79ce1eb3e1879e5a0c029ff7658b7950", kill_on_drop: false }`
[INFO] [stdout] 6b96206e77bf16da8099baf07574449e79ce1eb3e1879e5a0c029ff7658b7950
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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@sha256:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-07-24" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 20a3bc8fd0735039e89415bf06d5336b22e2676c284ec12b190b91f66d9d1bbb
[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" "20a3bc8fd0735039e89415bf06d5336b22e2676c284ec12b190b91f66d9d1bbb", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.3
[INFO] [stderr]    Compiling syn v1.0.5
[INFO] [stderr]    Compiling futures-core-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling futures-io-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling crossbeam-queue v0.1.2
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]    Compiling tokio-io v0.1.12
[INFO] [stderr]    Compiling crossbeam-epoch v0.7.2
[INFO] [stderr]    Compiling futures-sink-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling futures-channel-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling crossbeam-deque v0.7.1
[INFO] [stderr]    Compiling quote v1.0.2
[INFO] [stderr]    Compiling proc-macro-hack v0.5.9
[INFO] [stderr]    Compiling futures-join-macro-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling futures-select-macro-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling futures-util-preview v0.3.0-alpha.18
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/futures-util-preview-0.3.0-alpha.18/src/lib.rs:4:38
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![cfg_attr(feature = "async-await", feature(async_await))]
[INFO] [stdout]   |                                      ^^^^^^^^^^^^^^^^^^^^
[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 `futures-util-preview`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "20a3bc8fd0735039e89415bf06d5336b22e2676c284ec12b190b91f66d9d1bbb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "20a3bc8fd0735039e89415bf06d5336b22e2676c284ec12b190b91f66d9d1bbb", kill_on_drop: false }`
[INFO] [stdout] 20a3bc8fd0735039e89415bf06d5336b22e2676c284ec12b190b91f66d9d1bbb