[INFO] fetching crate proto-vulcan 0.1.4...
[INFO] testing proto-vulcan-0.1.4 against beta-2021-01-01 for beta-1.50-1
[INFO] extracting crate proto-vulcan 0.1.4 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate proto-vulcan 0.1.4 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 proto-vulcan 0.1.4
[INFO] finished tweaking crates.io crate proto-vulcan 0.1.4
[INFO] tweaked toml for crates.io crate proto-vulcan 0.1.4 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate crates.io crate proto-vulcan 0.1.4 already has a lockfile, it will not be regenerated
[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 proto-vulcan-macros v0.1.4
[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" "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] 15ca183deb82260d76fb3b9ce61b616f25ae37b38c7aed01b96d526c33b50e71
[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" "15ca183deb82260d76fb3b9ce61b616f25ae37b38c7aed01b96d526c33b50e71", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "15ca183deb82260d76fb3b9ce61b616f25ae37b38c7aed01b96d526c33b50e71", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "15ca183deb82260d76fb3b9ce61b616f25ae37b38c7aed01b96d526c33b50e71", kill_on_drop: false }`
[INFO] [stdout] 15ca183deb82260d76fb3b9ce61b616f25ae37b38c7aed01b96d526c33b50e71
[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" "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] f1186b7b4af91ac8c52c9b92fe8b6b029685a83e36aecb3e04fac332e2435271
[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" "f1186b7b4af91ac8c52c9b92fe8b6b029685a83e36aecb3e04fac332e2435271", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.48
[INFO] [stderr]    Compiling proto-vulcan-macros v0.1.4
[INFO] [stderr]    Compiling derivative v2.1.1
[INFO] [stderr]    Compiling proto-vulcan v0.1.4 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]    --> src/lib.rs:306:1
[INFO] [stdout]     |
[INFO] [stdout] 306 | #![feature(move_ref_pattern)]
[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 `proto-vulcan`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "f1186b7b4af91ac8c52c9b92fe8b6b029685a83e36aecb3e04fac332e2435271", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f1186b7b4af91ac8c52c9b92fe8b6b029685a83e36aecb3e04fac332e2435271", kill_on_drop: false }`
[INFO] [stdout] f1186b7b4af91ac8c52c9b92fe8b6b029685a83e36aecb3e04fac332e2435271