[INFO] cloning repository https://github.com/dac456/cabal-extract
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/dac456/cabal-extract" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdac456%2Fcabal-extract", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdac456%2Fcabal-extract'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 6d4ce572f25ea76dda873ce9a095229925060df7
[INFO] testing dac456/cabal-extract against 1.55.0 for beta-1.56-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdac456%2Fcabal-extract" "/workspace/builds/worker-67/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-67/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/dac456/cabal-extract 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/dac456/cabal-extract
[INFO] finished tweaking git repo https://github.com/dac456/cabal-extract
[INFO] tweaked toml for git repo https://github.com/dac456/cabal-extract written to /workspace/builds/worker-67/source/Cargo.toml
[INFO] crate git repo https://github.com/dac456/cabal-extract 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]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-67/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-67/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] 655a83489f0d61a417a49699c362e921728f1a2d6eaf8294537bc291e7fc70d2
[INFO] running `Command { std: "docker" "start" "-a" "655a83489f0d61a417a49699c362e921728f1a2d6eaf8294537bc291e7fc70d2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "655a83489f0d61a417a49699c362e921728f1a2d6eaf8294537bc291e7fc70d2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "655a83489f0d61a417a49699c362e921728f1a2d6eaf8294537bc291e7fc70d2", kill_on_drop: false }`
[INFO] [stdout] 655a83489f0d61a417a49699c362e921728f1a2d6eaf8294537bc291e7fc70d2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-67/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-67/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] 1b8c97b57e7f87462272544314f6d6068c65711e8ae1c1db81229993b6288c4c
[INFO] running `Command { std: "docker" "start" "-a" "1b8c97b57e7f87462272544314f6d6068c65711e8ae1c1db81229993b6288c4c", kill_on_drop: false }`
[INFO] [stderr]    Compiling byteorder v0.5.3
[INFO] [stderr]    Compiling byteorder v1.0.0
[INFO] [stderr]    Compiling bmp v0.2.0
[INFO] [stderr]    Compiling cabal-extract 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:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(step_by)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::fs`
[INFO] [stdout]  --> src/main.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | use std::fs;
[INFO] [stdout]   |     ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]    --> src/postprocess/superxbr.rs:103:5
[INFO] [stdout]     |
[INFO] [stdout] 103 |     (dw1 - dw2)
[INFO] [stdout]     |     ^^^^^^^^^^^ help: remove these parentheses
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `cabal-extract` due to 2 previous errors; 2 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "1b8c97b57e7f87462272544314f6d6068c65711e8ae1c1db81229993b6288c4c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1b8c97b57e7f87462272544314f6d6068c65711e8ae1c1db81229993b6288c4c", kill_on_drop: false }`
[INFO] [stdout] 1b8c97b57e7f87462272544314f6d6068c65711e8ae1c1db81229993b6288c4c