[INFO] cloning repository https://github.com/usbalbin/neural_network
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/usbalbin/neural_network" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fusbalbin%2Fneural_network"`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fusbalbin%2Fneural_network'...
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 8756dcd64ef0e5b239264f59ef5f6951d9494d4b
[INFO] testing usbalbin/neural_network against beta-2020-06-03 for beta-1.45-1
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fusbalbin%2Fneural_network" "/workspace/builds/worker-1/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/usbalbin/neural_network 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 git repo https://github.com/usbalbin/neural_network
[INFO] finished tweaking git repo https://github.com/usbalbin/neural_network
[INFO] tweaked toml for git repo https://github.com/usbalbin/neural_network written to /workspace/builds/worker-1/source/Cargo.toml
[INFO] crate git repo https://github.com/usbalbin/neural_network already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+beta-2020-06-03" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Updating git repository `https://github.com/usbalbin/linear_algebra.git`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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] f39d67182424b5bfa75df9a6a1adc430cde3e59efd7deff238c46f39b61da977
[INFO] running `"docker" "start" "-a" "f39d67182424b5bfa75df9a6a1adc430cde3e59efd7deff238c46f39b61da977"`
[INFO] [stderr] sudo: setrlimit(RLIMIT_CORE): Operation not permitted
[INFO] [stderr]    Compiling libc v0.2.34
[INFO] [stderr]    Compiling linear_algebra v0.1.5 (https://github.com/usbalbin/linear_algebra.git#4f5a6b80)
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stderr]  --> /opt/rustwide/cargo-home/git/checkouts/linear_algebra-aed142029d91cb17/4f5a6b8/src/lib.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(iterator_step_by)]
[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 `linear_algebra`.
[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 `"docker" "inspect" "f39d67182424b5bfa75df9a6a1adc430cde3e59efd7deff238c46f39b61da977"`
[INFO] running `"docker" "rm" "-f" "f39d67182424b5bfa75df9a6a1adc430cde3e59efd7deff238c46f39b61da977"`
[INFO] [stdout] f39d67182424b5bfa75df9a6a1adc430cde3e59efd7deff238c46f39b61da977