[INFO] crate libmussh 1.1.3 is already in cache
[INFO] testing libmussh-1.1.3 against beta-2020-07-24 for beta-1.46-1
[INFO] extracting crate libmussh 1.1.3 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate libmussh 1.1.3 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 crates.io crate libmussh 1.1.3
[INFO] finished tweaking crates.io crate libmussh 1.1.3
[INFO] tweaked toml for crates.io crate libmussh 1.1.3 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-07-24" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-07-24" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 7afab6fabf8d9aea4247715dbe10cc358a06bfe19bf512711c7dda9e1aefe2cb
[INFO] running `Command { std: "docker" "start" "-a" "7afab6fabf8d9aea4247715dbe10cc358a06bfe19bf512711c7dda9e1aefe2cb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7afab6fabf8d9aea4247715dbe10cc358a06bfe19bf512711c7dda9e1aefe2cb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7afab6fabf8d9aea4247715dbe10cc358a06bfe19bf512711c7dda9e1aefe2cb", kill_on_drop: false }`
[INFO] [stdout] 7afab6fabf8d9aea4247715dbe10cc358a06bfe19bf512711c7dda9e1aefe2cb
[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] e7ebf3e10967b6b13c7a454bf2432ab5f5cab143d84c8c733d33c242825db2b7
[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" "e7ebf3e10967b6b13c7a454bf2432ab5f5cab143d84c8c733d33c242825db2b7", kill_on_drop: false }`
[INFO] [stderr]    Compiling slog v2.5.2
[INFO] [stderr]    Compiling lazy_static v1.2.0
[INFO] [stderr]    Compiling wait_group v0.1.4
[INFO] [stderr]    Compiling libssh2-sys v0.2.18
[INFO] [stderr]    Compiling proc-macro-error v1.0.4
[INFO] [stderr]    Compiling getset v0.1.1
[INFO] [stderr]    Compiling slog-try v0.2.0
[INFO] [stderr]    Compiling ssh2 v0.8.2
[INFO] [stderr]    Compiling libmussh v1.1.3 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> 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`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "e7ebf3e10967b6b13c7a454bf2432ab5f5cab143d84c8c733d33c242825db2b7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e7ebf3e10967b6b13c7a454bf2432ab5f5cab143d84c8c733d33c242825db2b7", kill_on_drop: false }`
[INFO] [stdout] e7ebf3e10967b6b13c7a454bf2432ab5f5cab143d84c8c733d33c242825db2b7