[INFO] cloning repository https://github.com/booleancoercion/braille-image
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/booleancoercion/braille-image" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbooleancoercion%2Fbraille-image", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbooleancoercion%2Fbraille-image'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 829683f22428e9996414005b7690b62b56ad04d5
[INFO] testing booleancoercion/braille-image against 1.55.0 for beta-1.56-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbooleancoercion%2Fbraille-image" "/workspace/builds/worker-14/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-14/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/booleancoercion/braille-image on toolchain 1.55.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/booleancoercion/braille-image
[INFO] finished tweaking git repo https://github.com/booleancoercion/braille-image
[INFO] tweaked toml for git repo https://github.com/booleancoercion/braille-image written to /workspace/builds/worker-14/source/Cargo.toml
[INFO] crate git repo https://github.com/booleancoercion/braille-image already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded edge-detection v0.2.5
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 03b36cc95fd7c9d1e1756e975d29b9cbf1434fd45c0eedb41d62e59cf772b642
[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" "03b36cc95fd7c9d1e1756e975d29b9cbf1434fd45c0eedb41d62e59cf772b642", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "03b36cc95fd7c9d1e1756e975d29b9cbf1434fd45c0eedb41d62e59cf772b642", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "03b36cc95fd7c9d1e1756e975d29b9cbf1434fd45c0eedb41d62e59cf772b642", kill_on_drop: false }`
[INFO] [stdout] 03b36cc95fd7c9d1e1756e975d29b9cbf1434fd45c0eedb41d62e59cf772b642
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d8f648dfff306e68249428487d42696e6dc9c99c54b58ae3bd7bb2887e90a9c6
[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" "d8f648dfff306e68249428487d42696e6dc9c99c54b58ae3bd7bb2887e90a9c6", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.82
[INFO] [stderr]    Compiling syn v1.0.58
[INFO] [stderr]    Compiling weezl v0.1.3
[INFO] [stderr]    Compiling bytemuck v1.5.0
[INFO] [stderr]    Compiling miniz_oxide v0.4.3
[INFO] [stderr]    Compiling deflate v0.8.6
[INFO] [stderr]    Compiling yaml-rust v0.4.5
[INFO] [stderr]    Compiling crossbeam-epoch v0.9.1
[INFO] [stderr]    Compiling gif v0.11.1
[INFO] [stderr]    Compiling crossbeam-deque v0.8.0
[INFO] [stderr]    Compiling png v0.16.8
[INFO] [stderr]    Compiling num_cpus v1.13.0
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling rayon-core v1.9.0
[INFO] [stderr]    Compiling rayon v1.5.0
[INFO] [stderr]    Compiling proc-macro-error v1.0.4
[INFO] [stderr]    Compiling jpeg-decoder v0.1.20
[INFO] [stderr]    Compiling tiff v0.6.1
[INFO] [stderr]    Compiling clap_derive v3.0.0-beta.2
[INFO] [stderr]    Compiling image v0.23.12
[INFO] [stderr]    Compiling clap v3.0.0-beta.2
[INFO] [stderr]    Compiling edge-detection v0.2.5
[INFO] [stderr]    Compiling braille-image v0.1.1 (/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(assoc_char_funcs)]
[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 `braille-image` due to 2 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "d8f648dfff306e68249428487d42696e6dc9c99c54b58ae3bd7bb2887e90a9c6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d8f648dfff306e68249428487d42696e6dc9c99c54b58ae3bd7bb2887e90a9c6", kill_on_drop: false }`
[INFO] [stdout] d8f648dfff306e68249428487d42696e6dc9c99c54b58ae3bd7bb2887e90a9c6