[INFO] fetching crate ss-view-tree 0.1.1...
[INFO] checking ss-view-tree-0.1.1 against beta for pr-78714
[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
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "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" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "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-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@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+beta" "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] 1267c1ff23a3381e3c6f855b93de0d46583614c7d375246765c8cbdd18038697
[INFO] running `Command { std: "docker" "start" "-a" "1267c1ff23a3381e3c6f855b93de0d46583614c7d375246765c8cbdd18038697", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "1267c1ff23a3381e3c6f855b93de0d46583614c7d375246765c8cbdd18038697", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1267c1ff23a3381e3c6f855b93de0d46583614c7d375246765c8cbdd18038697", kill_on_drop: false }`
[INFO] [stdout] 1267c1ff23a3381e3c6f855b93de0d46583614c7d375246765c8cbdd18038697
[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=forbid" "-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@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+beta" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] e354500a1606c5807e2ffb142bc762557f8272a53040abcb3b95bfeb1c451808
[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" "e354500a1606c5807e2ffb142bc762557f8272a53040abcb3b95bfeb1c451808", kill_on_drop: false }`
[INFO] [stderr]    Compiling wasm-bindgen-shared v0.2.68
[INFO] [stderr]    Compiling bumpalo v3.4.0
[INFO] [stderr]     Checking scopeguard v0.3.3
[INFO] [stderr]    Compiling wasm-bindgen v0.2.68
[INFO] [stderr]     Checking itertools v0.8.2
[INFO] [stderr]    Compiling parking_lot_core v0.4.0
[INFO] [stderr]     Checking Inflector v0.11.4
[INFO] [stderr]     Checking lock_api v0.1.5
[INFO] [stderr]    Compiling wasm-bindgen-backend v0.2.68
[INFO] [stderr]     Checking parking_lot v0.7.1
[INFO] [stderr]     Checking once_cell v0.1.8
[INFO] [stderr]     Checking cached v0.8.1
[INFO] [stderr]    Compiling wasm-bindgen-macro-support v0.2.68
[INFO] [stderr]    Compiling wasm-bindgen-macro v0.2.68
[INFO] [stderr]     Checking js-sys v0.3.45
[INFO] [stderr]     Checking web-sys v0.3.45
[INFO] [stderr]     Checking ss-web-utils v0.1.1
[INFO] [stderr]     Checking 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" "e354500a1606c5807e2ffb142bc762557f8272a53040abcb3b95bfeb1c451808", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e354500a1606c5807e2ffb142bc762557f8272a53040abcb3b95bfeb1c451808", kill_on_drop: false }`
[INFO] [stdout] e354500a1606c5807e2ffb142bc762557f8272a53040abcb3b95bfeb1c451808