[INFO] fetching crate umbra-lang 0.20.0...
[INFO] testing umbra-lang-0.20.0 against 1.54.0 for beta-1.55-1
[INFO] extracting crate umbra-lang 0.20.0 into /workspace/builds/worker-63/source
[INFO] validating manifest of crates.io crate umbra-lang 0.20.0 on toolchain 1.54.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate umbra-lang 0.20.0
[INFO] finished tweaking crates.io crate umbra-lang 0.20.0
[INFO] tweaked toml for crates.io crate umbra-lang 0.20.0 written to /workspace/builds/worker-63/source/Cargo.toml
[INFO] crate crates.io crate umbra-lang 0.20.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded redox_liner v0.5.1
[INFO] [stderr]   Downloaded jemallocator v0.3.2
[INFO] [stderr]   Downloaded jemalloc-sys v0.3.2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-63/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-63/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] be7dd2f2fda6d54b5169a4d98e91b3002d938ffc8a8cf72b9efe33fbd02853ae
[INFO] running `Command { std: "docker" "start" "-a" "be7dd2f2fda6d54b5169a4d98e91b3002d938ffc8a8cf72b9efe33fbd02853ae", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "be7dd2f2fda6d54b5169a4d98e91b3002d938ffc8a8cf72b9efe33fbd02853ae", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "be7dd2f2fda6d54b5169a4d98e91b3002d938ffc8a8cf72b9efe33fbd02853ae", kill_on_drop: false }`
[INFO] [stdout] be7dd2f2fda6d54b5169a4d98e91b3002d938ffc8a8cf72b9efe33fbd02853ae
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-63/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-63/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 8fa6c9a2026c33094a8aff2af3dd1523363b893eaae14de3e9d628e4a7779247
[INFO] running `Command { std: "docker" "start" "-a" "8fa6c9a2026c33094a8aff2af3dd1523363b893eaae14de3e9d628e4a7779247", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.94
[INFO] [stderr]    Compiling cc v1.0.67
[INFO] [stderr]    Compiling fs_extra v1.2.0
[INFO] [stderr]    Compiling log v0.4.14
[INFO] [stderr]    Compiling either v1.6.1
[INFO] [stderr]    Compiling cfg-if v1.0.0
[INFO] [stderr]    Compiling bytecount v0.6.2
[INFO] [stderr]    Compiling termcolor v1.1.2
[INFO] [stderr]    Compiling maplit v1.0.2
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling num-integer v0.1.44
[INFO] [stderr]    Compiling num-bigint v0.4.0
[INFO] [stderr]    Compiling num-rational v0.4.0
[INFO] [stderr]    Compiling itertools v0.8.2
[INFO] [stderr]    Compiling itertools v0.10.0
[INFO] [stderr]    Compiling jemalloc-sys v0.3.2
[INFO] [stderr]    Compiling termion v1.5.6
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling env_logger v0.8.3
[INFO] [stderr]    Compiling redox_liner v0.5.1
[INFO] [stderr]    Compiling jemallocator v0.3.2
[INFO] [stderr]    Compiling umbra-lang v0.20.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:37:1
[INFO] [stdout]    |
[INFO] [stdout] 37 | #![feature(const_generics)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:39:1
[INFO] [stdout]    |
[INFO] [stdout] 39 | #![feature(iter_intersperse)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `umbra-lang`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "8fa6c9a2026c33094a8aff2af3dd1523363b893eaae14de3e9d628e4a7779247", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8fa6c9a2026c33094a8aff2af3dd1523363b893eaae14de3e9d628e4a7779247", kill_on_drop: false }`
[INFO] [stdout] 8fa6c9a2026c33094a8aff2af3dd1523363b893eaae14de3e9d628e4a7779247
