[INFO] crate register 0.3.3 is already in cache
[INFO] checking register-0.3.3 against beta-2019-10-27 for pr-65897
[INFO] extracting crate register 0.3.3 into /workspace/builds/worker-7/source
[INFO] validating manifest of crates.io crate register 0.3.3 on toolchain beta-2019-10-27
[INFO] running `"/workspace/cargo-home/bin/cargo" "+beta-2019-10-27" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking crates.io crate register 0.3.3
[INFO] finished tweaking crates.io crate register 0.3.3
[INFO] tweaked toml for crates.io crate register 0.3.3 written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] running `"/workspace/cargo-home/bin/cargo" "+beta-2019-10-27" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/workspace/cargo-home/bin/cargo" "+beta-2019-10-27" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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=allow" "-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" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2019-10-27" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] 73a94698c91002221965d0d88b1c31509f81ffb66bec1f2a22228a5d8777e73c
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `"docker" "start" "-a" "73a94698c91002221965d0d88b1c31509f81ffb66bec1f2a22228a5d8777e73c"`
[INFO] [stderr]     Checking tock-registers v0.3.0
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stderr]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/tock-registers-0.3.0/src/lib.rs:5:1
[INFO] [stderr]   |
[INFO] [stderr] 5 | #![feature(const_fn)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr] error: could not compile `tock-registers`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "73a94698c91002221965d0d88b1c31509f81ffb66bec1f2a22228a5d8777e73c"`
[INFO] running `"docker" "rm" "-f" "73a94698c91002221965d0d88b1c31509f81ffb66bec1f2a22228a5d8777e73c"`
[INFO] [stdout] 73a94698c91002221965d0d88b1c31509f81ffb66bec1f2a22228a5d8777e73c