[INFO] cloning repository https://github.com/popey456963/lingo
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/popey456963/lingo" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fpopey456963%2Flingo", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fpopey456963%2Flingo'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 49682c180974983fd7afeef50784dcca4b9030b2
[INFO] testing popey456963/lingo against 1.91.0 for beta-1.92-2
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fpopey456963%2Flingo" "/workspace/builds/worker-2-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2-tc1/source'...
[INFO] [stderr] done.
[INFO] removed /workspace/builds/worker-2-tc1/source/.cargo/config.toml
[INFO] started tweaking git repo https://github.com/popey456963/lingo
[INFO] finished tweaking git repo https://github.com/popey456963/lingo
[INFO] tweaked toml for git repo https://github.com/popey456963/lingo written to /workspace/builds/worker-2-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/popey456963/lingo on toolchain 1.91.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.91.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/popey456963/lingo already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.91.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: unused manifest key: unstable
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+1.91.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] aaa3fa6bac7a4d4403ed79add14ff5390a70c62b13133b069e5a2f8e0440436d
[INFO] running `Command { std: "docker" "start" "-a" "aaa3fa6bac7a4d4403ed79add14ff5390a70c62b13133b069e5a2f8e0440436d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "aaa3fa6bac7a4d4403ed79add14ff5390a70c62b13133b069e5a2f8e0440436d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "aaa3fa6bac7a4d4403ed79add14ff5390a70c62b13133b069e5a2f8e0440436d", kill_on_drop: false }`
[INFO] [stdout] aaa3fa6bac7a4d4403ed79add14ff5390a70c62b13133b069e5a2f8e0440436d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/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" "RUSTDOCFLAGS=--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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+1.91.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 0e9f08aa3c43f9adf77f1b434623a34b008478ddd6cb8d241990af7d939f7473
[INFO] running `Command { std: "docker" "start" "-a" "0e9f08aa3c43f9adf77f1b434623a34b008478ddd6cb8d241990af7d939f7473", kill_on_drop: false }`
[INFO] [stderr] warning: unused manifest key: unstable
[INFO] [stderr]    Compiling autocfg v1.0.1
[INFO] [stderr]    Compiling crossbeam-utils v0.8.5
[INFO] [stderr]    Compiling lazy_static v1.4.0
[INFO] [stderr]    Compiling crossbeam-epoch v0.9.5
[INFO] [stderr]    Compiling libc v0.2.112
[INFO] [stderr]    Compiling scopeguard v1.1.0
[INFO] [stderr]    Compiling rayon-core v1.9.1
[INFO] [stderr]    Compiling either v1.6.1
[INFO] [stderr]    Compiling memoffset v0.6.5
[INFO] [stderr]    Compiling rayon v1.5.1
[INFO] [stderr]    Compiling crossbeam-channel v0.5.1
[INFO] [stderr]    Compiling crossbeam-deque v0.8.1
[INFO] [stderr]    Compiling num_cpus v1.13.1
[INFO] [stderr]    Compiling lingo v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/main.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(iter_intersperse)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `lingo` (bin "lingo") due to 1 previous error
[INFO] running `Command { std: "docker" "inspect" "0e9f08aa3c43f9adf77f1b434623a34b008478ddd6cb8d241990af7d939f7473", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0e9f08aa3c43f9adf77f1b434623a34b008478ddd6cb8d241990af7d939f7473", kill_on_drop: false }`
[INFO] [stdout] 0e9f08aa3c43f9adf77f1b434623a34b008478ddd6cb8d241990af7d939f7473