[INFO] cloning repository https://github.com/rHermes/aoc-rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/rHermes/aoc-rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FrHermes%2Faoc-rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FrHermes%2Faoc-rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 59b9eeefd7a0410df4b62048ae198306d887ad3a
[INFO] testing rHermes/aoc-rust against 1.49.0 for beta-1.50-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FrHermes%2Faoc-rust" "/workspace/builds/worker-6/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/rHermes/aoc-rust on toolchain 1.49.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/rHermes/aoc-rust
[INFO] finished tweaking git repo https://github.com/rHermes/aoc-rust
[INFO] tweaked toml for git repo https://github.com/rHermes/aoc-rust written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] crate git repo https://github.com/rHermes/aoc-rust already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "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" "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" "+1.49.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 3efe8c6001bb00ebb07366198e9b65d85011f3618d3be9501146d82ba0e4c9af
[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" "3efe8c6001bb00ebb07366198e9b65d85011f3618d3be9501146d82ba0e4c9af", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3efe8c6001bb00ebb07366198e9b65d85011f3618d3be9501146d82ba0e4c9af", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3efe8c6001bb00ebb07366198e9b65d85011f3618d3be9501146d82ba0e4c9af", kill_on_drop: false }`
[INFO] [stdout] 3efe8c6001bb00ebb07366198e9b65d85011f3618d3be9501146d82ba0e4c9af
[INFO] running `Command { std: "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" "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" "+1.49.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 734cc33dde1c4d8b3e1f386a4cb455d0fa2f380f72d902d3361f77831ada194e
[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" "734cc33dde1c4d8b3e1f386a4cb455d0fa2f380f72d902d3361f77831ada194e", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.80
[INFO] [stderr]    Compiling syn v1.0.53
[INFO] [stderr]    Compiling memchr v2.3.4
[INFO] [stderr]    Compiling futures-core v0.3.8
[INFO] [stderr]    Compiling cc v1.0.65
[INFO] [stderr]    Compiling proc-macro-hack v0.5.19
[INFO] [stderr]    Compiling futures-sink v0.3.8
[INFO] [stderr]    Compiling pin-project-internal v0.4.27
[INFO] [stderr]    Compiling once_cell v1.5.2
[INFO] [stderr]    Compiling pin-project-lite v0.1.11
[INFO] [stderr]    Compiling futures-io v0.3.8
[INFO] [stderr]    Compiling pin-project-lite v0.2.0
[INFO] [stderr]    Compiling native-tls v0.2.6
[INFO] [stderr]    Compiling tinyvec_macros v0.1.0
[INFO] [stderr]    Compiling byteorder v1.3.4
[INFO] [stderr]    Compiling httpdate v0.3.2
[INFO] [stderr]    Compiling encoding_rs v0.8.26
[INFO] [stderr]    Compiling mime v0.3.16
[INFO] [stderr]    Compiling base64 v0.13.0
[INFO] [stderr]    Compiling ipnet v2.3.0
[INFO] [stderr]    Compiling either v1.6.1
[INFO] [stderr]    Compiling tracing-core v0.1.17
[INFO] [stderr]    Compiling unicase v2.6.0
[INFO] [stderr]    Compiling form_urlencoded v1.0.0
[INFO] [stderr]    Compiling tinyvec v1.1.0
[INFO] [stderr]    Compiling futures-channel v0.3.8
[INFO] [stderr]    Compiling futures-task v0.3.8
[INFO] [stderr]    Compiling itertools v0.9.0
[INFO] [stderr]    Compiling want v0.3.0
[INFO] [stderr]    Compiling serde_json v1.0.59
[INFO] [stderr]    Compiling serde_urlencoded v0.7.0
[INFO] [stderr]    Compiling tracing v0.1.22
[INFO] [stderr]    Compiling block-buffer v0.7.3
[INFO] [stderr]    Compiling mime_guess v2.0.3
[INFO] [stderr]    Compiling md-5 v0.8.0
[INFO] [stderr]    Compiling sha2 v0.8.2
[INFO] [stderr]    Compiling openssl-sys v0.9.58
[INFO] [stderr]    Compiling net2 v0.2.36
[INFO] [stderr]    Compiling iovec v0.1.4
[INFO] [stderr]    Compiling num_cpus v1.13.0
[INFO] [stderr]    Compiling signal-hook-registry v1.2.2
[INFO] [stderr]    Compiling socket2 v0.3.17
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling dirs-sys v0.3.5
[INFO] [stderr]    Compiling unicode-normalization v0.1.16
[INFO] [stderr]    Compiling colored v1.9.3
[INFO] [stderr]    Compiling dirs v2.0.2
[INFO] [stderr]    Compiling mio v0.6.22
[INFO] [stderr]    Compiling openssl v0.10.30
[INFO] [stderr]    Compiling idna v0.2.0
[INFO] [stderr]    Compiling mio-uds v0.6.8
[INFO] [stderr]    Compiling url v2.2.0
[INFO] [stderr]    Compiling pin-project-internal v1.0.2
[INFO] [stderr]    Compiling tokio-macros v0.2.6
[INFO] [stderr]    Compiling futures-macro v0.3.8
[INFO] [stderr]    Compiling alloc_counter_macro v0.0.2
[INFO] [stderr]    Compiling alloc_counter v0.0.4
[INFO] [stderr]    Compiling tokio v0.2.23
[INFO] [stderr]    Compiling pin-project v1.0.2
[INFO] [stderr]    Compiling futures-util v0.3.8
[INFO] [stderr]    Compiling pin-project v0.4.27
[INFO] [stderr]    Compiling tracing-futures v0.2.4
[INFO] [stderr]    Compiling tokio-util v0.3.1
[INFO] [stderr]    Compiling tokio-tls v0.3.1
[INFO] [stderr]    Compiling h2 v0.2.7
[INFO] [stderr]    Compiling futures-executor v0.3.8
[INFO] [stderr]    Compiling futures v0.3.8
[INFO] [stderr]    Compiling hyper v0.13.9
[INFO] [stderr]    Compiling hyper-tls v0.4.3
[INFO] [stderr]    Compiling reqwest v0.10.9
[INFO] [stderr]    Compiling aoc v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(bool_to_option)]
[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 `aoc`
[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" "734cc33dde1c4d8b3e1f386a4cb455d0fa2f380f72d902d3361f77831ada194e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "734cc33dde1c4d8b3e1f386a4cb455d0fa2f380f72d902d3361f77831ada194e", kill_on_drop: false }`
[INFO] [stdout] 734cc33dde1c4d8b3e1f386a4cb455d0fa2f380f72d902d3361f77831ada194e