[INFO] fetching crate ss-view-tree 0.1.1...
[INFO] testing ss-view-tree-0.1.1 against beta-2021-01-01 for beta-1.50-1
[INFO] extracting crate ss-view-tree 0.1.1 into /workspace/builds/worker-2/source
[INFO] validating manifest of crates.io crate ss-view-tree 0.1.1 on toolchain beta-2021-01-01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate ss-view-tree 0.1.1
[INFO] finished tweaking crates.io crate ss-view-tree 0.1.1
[INFO] tweaked toml for crates.io crate ss-view-tree 0.1.1 written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded ss-trees v0.1.1
[INFO] [stderr]   Downloaded Inflector v0.11.4
[INFO] [stderr]   Downloaded ss-web-utils v0.1.1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "rustops/crates-build-env@sha256:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 5db9f98d6cefae769aee12e0115c2ce5479353423b257f9f7a990ec605872681
[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" "5db9f98d6cefae769aee12e0115c2ce5479353423b257f9f7a990ec605872681", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5db9f98d6cefae769aee12e0115c2ce5479353423b257f9f7a990ec605872681", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5db9f98d6cefae769aee12e0115c2ce5479353423b257f9f7a990ec605872681", kill_on_drop: false }`
[INFO] [stdout] 5db9f98d6cefae769aee12e0115c2ce5479353423b257f9f7a990ec605872681
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "rustops/crates-build-env@sha256:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4c14b6034432a9be52caf6b2bc0c8eb31c8709275a53e6534e113cedee423e91
[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" "4c14b6034432a9be52caf6b2bc0c8eb31c8709275a53e6534e113cedee423e91", kill_on_drop: false }`
[INFO] [stderr]    Compiling wasm-bindgen-shared v0.2.69
[INFO] [stderr]    Compiling bumpalo v3.4.0
[INFO] [stderr]    Compiling wasm-bindgen v0.2.69
[INFO] [stderr]    Compiling lock_api v0.1.5
[INFO] [stderr]    Compiling itertools v0.8.2
[INFO] [stderr]    Compiling serde v1.0.118
[INFO] [stderr]    Compiling Inflector v0.11.4
[INFO] [stderr]    Compiling parking_lot v0.7.1
[INFO] [stderr]    Compiling once_cell v0.1.8
[INFO] [stderr]    Compiling cached v0.8.1
[INFO] [stderr]    Compiling wasm-bindgen-backend v0.2.69
[INFO] [stderr]    Compiling wasm-bindgen-macro-support v0.2.69
[INFO] [stderr]    Compiling wasm-bindgen-macro v0.2.69
[INFO] [stderr]    Compiling serde_json v1.0.61
[INFO] [stderr]    Compiling js-sys v0.3.46
[INFO] [stderr]    Compiling web-sys v0.3.46
[INFO] [stderr]    Compiling ss-web-utils v0.1.1
[INFO] [stderr]    Compiling ss-trees v0.1.1
[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/ss-trees-0.1.1/src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(vec_remove_item)]
[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 `ss-trees`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "4c14b6034432a9be52caf6b2bc0c8eb31c8709275a53e6534e113cedee423e91", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4c14b6034432a9be52caf6b2bc0c8eb31c8709275a53e6534e113cedee423e91", kill_on_drop: false }`
[INFO] [stdout] 4c14b6034432a9be52caf6b2bc0c8eb31c8709275a53e6534e113cedee423e91