[INFO] fetching crate robt 0.2.0...
[INFO] testing robt-0.2.0 against 1.54.0 for beta-1.55-1
[INFO] extracting crate robt 0.2.0 into /workspace/builds/worker-52/source
[INFO] validating manifest of crates.io crate robt 0.2.0 on toolchain 1.54.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate robt 0.2.0
[INFO] finished tweaking crates.io crate robt 0.2.0
[INFO] tweaked toml for crates.io crate robt 0.2.0 written to /workspace/builds/worker-52/source/Cargo.toml
[INFO] crate crates.io crate robt 0.2.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-52/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-52/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] cb1562cbdace8fc430a237f4351a2ff0c1cea4a5f5cf0bfae513c8f48cd041a3
[INFO] running `Command { std: "docker" "start" "-a" "cb1562cbdace8fc430a237f4351a2ff0c1cea4a5f5cf0bfae513c8f48cd041a3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "cb1562cbdace8fc430a237f4351a2ff0c1cea4a5f5cf0bfae513c8f48cd041a3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cb1562cbdace8fc430a237f4351a2ff0c1cea4a5f5cf0bfae513c8f48cd041a3", kill_on_drop: false }`
[INFO] [stdout] cb1562cbdace8fc430a237f4351a2ff0c1cea4a5f5cf0bfae513c8f48cd041a3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-52/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-52/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 1b41e481e624b0bd3b5a9846996423a22e88bf3406b7ea3fb75cc4432681c8fe
[INFO] running `Command { std: "docker" "start" "-a" "1b41e481e624b0bd3b5a9846996423a22e88bf3406b7ea3fb75cc4432681c8fe", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.24
[INFO] [stderr]    Compiling unicode-xid v0.2.1
[INFO] [stderr]    Compiling syn v1.0.53
[INFO] [stderr]    Compiling version_check v0.9.2
[INFO] [stderr]    Compiling unicode-segmentation v1.7.1
[INFO] [stderr]    Compiling libc v0.2.81
[INFO] [stderr]    Compiling log v0.4.11
[INFO] [stderr]    Compiling xorfilter-rs v0.3.0
[INFO] [stderr]    Compiling proc-macro-error-attr v0.4.12
[INFO] [stderr]    Compiling proc-macro-error v0.4.12
[INFO] [stderr]    Compiling heck v0.3.1
[INFO] [stderr]    Compiling quote v1.0.7
[INFO] [stderr]    Compiling fs2 v0.4.3
[INFO] [stderr]    Compiling syn-mid v0.5.1
[INFO] [stderr]    Compiling derive_arbitrary v0.4.7
[INFO] [stderr]    Compiling arbitrary v0.4.7
[INFO] [stderr]    Compiling mkit-derive v0.3.0
[INFO] [stderr]    Compiling mkit v0.4.0
[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/mkit-0.4.0/src/lib.rs:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![feature(min_const_generics)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove the attribute
[INFO] [stdout]   |
[INFO] [stdout]   = help: the feature `min_const_generics` has been stable since 1.51.0 and no longer requires an attribute to enable
[INFO] [stdout] 
[INFO] [stdout] 
[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/mkit-0.4.0/src/lib.rs:5:1
[INFO] [stdout]   |
[INFO] [stdout] 5 | #![feature(total_cmp)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `mkit`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "1b41e481e624b0bd3b5a9846996423a22e88bf3406b7ea3fb75cc4432681c8fe", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1b41e481e624b0bd3b5a9846996423a22e88bf3406b7ea3fb75cc4432681c8fe", kill_on_drop: false }`
[INFO] [stdout] 1b41e481e624b0bd3b5a9846996423a22e88bf3406b7ea3fb75cc4432681c8fe
