[INFO] updating cached repository https://github.com/robot-head/led_dash
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/big/crater/work/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune"`
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 2d6066796182b919cddbabb9f7a854ac1eefab0b
[INFO] testing robot-head/led_dash against 1.38.0 for beta-1.39-1
[INFO] running `"git" "clone" "work/cache/git-repos/https%3A%2F%2Fgithub.com%2Frobot-head%2Fled_dash" "work/builds/worker-2/source"`
[INFO] [stderr] Cloning into 'work/builds/worker-2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/robot-head/led_dash on toolchain 1.38.0
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+1.38.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/robot-head/led_dash
[INFO] finished tweaking git repo https://github.com/robot-head/led_dash
[INFO] tweaked toml for git repo https://github.com/robot-head/led_dash written to work/builds/worker-2/source/Cargo.toml
[INFO] crate git repo https://github.com/robot-head/led_dash already has a lockfile, it will not be regenerated
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+1.38.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"docker" "create" "-v" "/big/crater/work/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/big/crater/work/builds/worker-2/source:/opt/rustwide/workdir:ro,Z" "-v" "/big/crater/work/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/big/crater/work/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "MAP_USER_ID=1000" "-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" "+1.38.0" "build" "--frozen"`
[INFO] [stdout] 7e871aac05bf4e34c47f67296b6490c743844ffa7a18b1d0bb1e33b8901980ae
[INFO] running `"docker" "start" "-a" "7e871aac05bf4e34c47f67296b6490c743844ffa7a18b1d0bb1e33b8901980ae"`
[INFO] [stderr]    Compiling memchr v2.0.1
[INFO] [stderr]    Compiling filetime v0.1.15
[INFO] [stderr]    Compiling base64 v0.7.0
[INFO] [stderr]    Compiling threadpool v1.7.1
[INFO] [stderr]    Compiling clap v2.31.2
[INFO] [stderr]    Compiling uuid v0.1.18
[INFO] [stderr]    Compiling enum_primitive v0.1.1
[INFO] [stderr]    Compiling brotli-sys v0.2.1
[INFO] [stderr]    Compiling chrono v0.4.2
[INFO] [stderr]    Compiling serde_json v1.0.19
[INFO] [stderr]    Compiling num v0.1.42
[INFO] [stderr]    Compiling chrono v0.2.25
[INFO] [stderr]    Compiling gzip-header v0.1.2
[INFO] [stderr]    Compiling brotli2 v0.2.2
[INFO] [stderr]    Compiling twoway v0.1.8
[INFO] [stderr]    Compiling url v0.2.38
[INFO] [stderr]    Compiling deflate v0.7.18
[INFO] [stderr]    Compiling multipart v0.13.6
[INFO] [stderr]    Compiling tiny_http v0.5.9
[INFO] [stderr]    Compiling rouille v2.1.0
[INFO] [stderr]    Compiling led_dash v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stderr]  --> src/main.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(proc_macro)]
[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 `led_dash`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "7e871aac05bf4e34c47f67296b6490c743844ffa7a18b1d0bb1e33b8901980ae"`
[INFO] running `"docker" "rm" "-f" "7e871aac05bf4e34c47f67296b6490c743844ffa7a18b1d0bb1e33b8901980ae"`
[INFO] [stdout] 7e871aac05bf4e34c47f67296b6490c743844ffa7a18b1d0bb1e33b8901980ae