[INFO] fetching crate vesc-comm 0.1.1...
[INFO] testing vesc-comm-0.1.1 against beta-2020-06-03 for beta-1.45-1
[INFO] extracting crate vesc-comm 0.1.1 into /workspace/builds/worker-6/source
[INFO] validating manifest of crates.io crate vesc-comm 0.1.1 on toolchain beta-2020-06-03
[INFO] running `"/workspace/cargo-home/bin/cargo" "+beta-2020-06-03" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking crates.io crate vesc-comm 0.1.1
[INFO] finished tweaking crates.io crate vesc-comm 0.1.1
[INFO] tweaked toml for crates.io crate vesc-comm 0.1.1 written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] running `"/workspace/cargo-home/bin/cargo" "+beta-2020-06-03" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/workspace/cargo-home/bin/cargo" "+beta-2020-06-03" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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=warn" "-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-2020-06-03" "build" "--frozen"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 1bd68122a0817a833f22046283e44585bb8a8f8e5c1ff5bddc2bd6bb80717c2d
[INFO] running `"docker" "start" "-a" "1bd68122a0817a833f22046283e44585bb8a8f8e5c1ff5bddc2bd6bb80717c2d"`
[INFO] [stderr] sudo: setrlimit(RLIMIT_CORE): Operation not permitted
[INFO] [stderr]    Compiling typenum v1.12.0
[INFO] [stderr]    Compiling byteorder v1.3.4
[INFO] [stderr]    Compiling stable_deref_trait v1.1.1
[INFO] [stderr]    Compiling crc16 v0.4.0
[INFO] [stderr]    Compiling heapless v0.4.4
[INFO] [stderr]    Compiling nb v0.1.2
[INFO] [stderr]    Compiling void v1.0.2
[INFO] [stderr]    Compiling failure v0.1.8
[INFO] [stderr]    Compiling embedded-hal v0.2.3
[INFO] [stderr]    Compiling hash32 v0.1.1
[INFO] [stderr]    Compiling generic-array v0.13.2
[INFO] [stderr]    Compiling generic-array v0.12.3
[INFO] [stderr]    Compiling generic-array v0.11.1
[INFO] [stderr]    Compiling as-slice v0.1.3
[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/heapless-0.4.4/src/lib.rs:92:35
[INFO] [stderr]    |
[INFO] [stderr] 92 | #![cfg_attr(feature = "const-fn", feature(const_fn))]
[INFO] [stderr]    |                                   ^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[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/heapless-0.4.4/src/lib.rs:93:35
[INFO] [stderr]    |
[INFO] [stderr] 93 | #![cfg_attr(feature = "const-fn", feature(untagged_unions))]
[INFO] [stderr]    |                                   ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 2 previous errors
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr] error: could not compile `heapless`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "1bd68122a0817a833f22046283e44585bb8a8f8e5c1ff5bddc2bd6bb80717c2d"`
[INFO] running `"docker" "rm" "-f" "1bd68122a0817a833f22046283e44585bb8a8f8e5c1ff5bddc2bd6bb80717c2d"`
[INFO] [stdout] 1bd68122a0817a833f22046283e44585bb8a8f8e5c1ff5bddc2bd6bb80717c2d