[INFO] cloning repository https://github.com/ear7h/lang2
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/ear7h/lang2" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fear7h%2Flang2", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fear7h%2Flang2'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] beb1449fa834d9b9d550631159fff0c44d1b8a53
[INFO] testing ear7h/lang2 against 1.55.0 for beta-1.56-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fear7h%2Flang2" "/workspace/builds/worker-8/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-8/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/ear7h/lang2 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/ear7h/lang2
[INFO] finished tweaking git repo https://github.com/ear7h/lang2
[INFO] tweaked toml for git repo https://github.com/ear7h/lang2 written to /workspace/builds/worker-8/source/Cargo.toml
[INFO] crate git repo https://github.com/ear7h/lang2 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] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded lasso v0.5.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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] cd238f7c72d88f7a9c2f72b135ea5a201843ec94fb0ed6d207a23fced404c90d
[INFO] running `Command { std: "docker" "start" "-a" "cd238f7c72d88f7a9c2f72b135ea5a201843ec94fb0ed6d207a23fced404c90d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "cd238f7c72d88f7a9c2f72b135ea5a201843ec94fb0ed6d207a23fced404c90d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cd238f7c72d88f7a9c2f72b135ea5a201843ec94fb0ed6d207a23fced404c90d", kill_on_drop: false }`
[INFO] [stdout] cd238f7c72d88f7a9c2f72b135ea5a201843ec94fb0ed6d207a23fced404c90d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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] 2fab408a0edfbece5a4d805ca2d287b50e4a3a8ff69db1ad719d30577476d699
[INFO] running `Command { std: "docker" "start" "-a" "2fab408a0edfbece5a4d805ca2d287b50e4a3a8ff69db1ad719d30577476d699", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling proc-macro2 v1.0.24
[INFO] [stderr]    Compiling libc v0.2.92
[INFO] [stderr]    Compiling unicode-xid v0.2.1
[INFO] [stderr]    Compiling ahash v0.4.7
[INFO] [stderr]    Compiling peg-runtime v0.6.3 (https://github.com/kevinmehall/rust-peg?branch=master#7d03e426)
[INFO] [stderr]    Compiling cfg-if v1.0.0
[INFO] [stderr]    Compiling hashbrown v0.9.1
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]    Compiling num_cpus v1.13.0
[INFO] [stderr]    Compiling dashmap v4.0.2
[INFO] [stderr]    Compiling peg-macros v0.6.3 (https://github.com/kevinmehall/rust-peg?branch=master#7d03e426)
[INFO] [stderr]    Compiling lasso v0.5.0
[INFO] [stderr]    Compiling peg v0.6.3 (https://github.com/kevinmehall/rust-peg?branch=master#7d03e426)
[INFO] [stderr]    Compiling lang2 v0.1.0 (/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(box_patterns, box_syntax)]
[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 `lang2` due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "2fab408a0edfbece5a4d805ca2d287b50e4a3a8ff69db1ad719d30577476d699", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2fab408a0edfbece5a4d805ca2d287b50e4a3a8ff69db1ad719d30577476d699", kill_on_drop: false }`
[INFO] [stdout] 2fab408a0edfbece5a4d805ca2d287b50e4a3a8ff69db1ad719d30577476d699