[INFO] cloning repository https://github.com/rustyhorde/mussh
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/rustyhorde/mussh" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frustyhorde%2Fmussh", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frustyhorde%2Fmussh'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] d2160d031b1bf31ed6784cbefe4e8611e366574e
[INFO] testing rustyhorde/mussh against 1.55.0 for beta-1.56-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frustyhorde%2Fmussh" "/workspace/builds/worker-0/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/rustyhorde/mussh on toolchain 1.55.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/rustyhorde/mussh
[INFO] finished tweaking git repo https://github.com/rustyhorde/mussh
[INFO] tweaked toml for git repo https://github.com/rustyhorde/mussh written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] crate git repo https://github.com/rustyhorde/mussh already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "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-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] ee42efb43da2d4447ffb3d074a357a93ff8c9b92b475cceae172c538176dbaac
[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" "ee42efb43da2d4447ffb3d074a357a93ff8c9b92b475cceae172c538176dbaac", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ee42efb43da2d4447ffb3d074a357a93ff8c9b92b475cceae172c538176dbaac", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ee42efb43da2d4447ffb3d074a357a93ff8c9b92b475cceae172c538176dbaac", kill_on_drop: false }`
[INFO] [stdout] ee42efb43da2d4447ffb3d074a357a93ff8c9b92b475cceae172c538176dbaac
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4b447f3b58bbe1baaa477e211b1d317056db1ee0b57045089d21ba108f609cd8
[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" "4b447f3b58bbe1baaa477e211b1d317056db1ee0b57045089d21ba108f609cd8", kill_on_drop: false }`
[INFO] [stderr]    Compiling slog v2.7.0
[INFO] [stderr]    Compiling lazy_static v1.2.0
[INFO] [stderr]    Compiling wait_group v0.1.4
[INFO] [stderr]    Compiling libz-sys v1.1.3
[INFO] [stderr]    Compiling libssh2-sys v0.2.21
[INFO] [stderr]    Compiling libsqlite3-sys v0.22.2
[INFO] [stderr]    Compiling serde v1.0.130
[INFO] [stderr]    Compiling parking_lot_core v0.7.2
[INFO] [stderr]    Compiling openssl-sys v0.9.66
[INFO] [stderr]    Compiling proc-macro-error-attr v1.0.4
[INFO] [stderr]    Compiling dirs-next v2.0.0
[INFO] [stderr]    Compiling clap v2.33.3
[INFO] [stderr]    Compiling indexmap v1.7.0
[INFO] [stderr]    Compiling chrono v0.4.19
[INFO] [stderr]    Compiling term v0.7.0
[INFO] [stderr]    Compiling crossbeam-utils v0.7.2
[INFO] [stderr]    Compiling parking_lot v0.10.2
[INFO] [stderr]    Compiling crossbeam-channel v0.4.4
[INFO] [stderr]    Compiling proc-macro-error v1.0.4
[INFO] [stderr]    Compiling rusqlite v0.25.3
[INFO] [stderr]    Compiling slog-try v0.2.0
[INFO] [stderr]    Compiling slog-term v2.8.0
[INFO] [stderr]    Compiling getset v0.1.1
[INFO] [stderr]    Compiling slog-async v2.5.0
[INFO] [stderr]    Compiling toml v0.5.8
[INFO] [stderr]    Compiling ssh2 v0.9.1
[INFO] [stderr]    Compiling libmussh v1.1.3
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/libmussh-1.1.3/src/lib.rs:10:1
[INFO] [stdout]    |
[INFO] [stdout] 10 | #![feature(crate_visibility_modifier, error_iter)]
[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 `libmussh` due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "4b447f3b58bbe1baaa477e211b1d317056db1ee0b57045089d21ba108f609cd8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4b447f3b58bbe1baaa477e211b1d317056db1ee0b57045089d21ba108f609cd8", kill_on_drop: false }`
[INFO] [stdout] 4b447f3b58bbe1baaa477e211b1d317056db1ee0b57045089d21ba108f609cd8