[INFO] fetching crate lark-test 0.1.0...
[INFO] documenting lark-test-0.1.0 against 1.54.0 for beta-1.55-rustdoc-1
[INFO] extracting crate lark-test 0.1.0 into /workspace/builds/worker-79/source
[INFO] validating manifest of crates.io crate lark-test 0.1.0 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 lark-test 0.1.0
[INFO] finished tweaking crates.io crate lark-test 0.1.0
[INFO] tweaked toml for crates.io crate lark-test 0.1.0 written to /workspace/builds/worker-79/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "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-79/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-79/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] bf0ffbe9609951aace9d14dcd77730b4b380b869bb66c01c9a7a81fdbb8ddd40
[INFO] running `Command { std: "docker" "start" "-a" "bf0ffbe9609951aace9d14dcd77730b4b380b869bb66c01c9a7a81fdbb8ddd40", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "bf0ffbe9609951aace9d14dcd77730b4b380b869bb66c01c9a7a81fdbb8ddd40", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bf0ffbe9609951aace9d14dcd77730b4b380b869bb66c01c9a7a81fdbb8ddd40", kill_on_drop: false }`
[INFO] [stdout] bf0ffbe9609951aace9d14dcd77730b4b380b869bb66c01c9a7a81fdbb8ddd40
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-79/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-79/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" "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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] db4ac1fc63f804ad1c5f2e2c10ceed2c179a17bb128ace77ae4760397f48ddc0
[INFO] running `Command { std: "docker" "start" "-a" "db4ac1fc63f804ad1c5f2e2c10ceed2c179a17bb128ace77ae4760397f48ddc0", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling autocfg v0.1.7
[INFO] [stderr]    Compiling syn v1.0.74
[INFO] [stderr]     Checking tinyvec_macros v0.1.0
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]     Checking hashbrown v0.11.2
[INFO] [stderr]    Compiling ryu v1.0.5
[INFO] [stderr]     Checking either v1.6.1
[INFO] [stderr]     Checking rustc-hash v1.1.0
[INFO] [stderr]    Compiling serde_json v1.0.66
[INFO] [stderr]     Checking itoa v0.4.7
[INFO] [stderr]     Checking termcolor v1.1.2
[INFO] [stderr]     Checking unicode-xid v0.1.0
[INFO] [stderr]    Compiling crossbeam-utils v0.8.5
[INFO] [stderr]    Compiling crossbeam-epoch v0.9.5
[INFO] [stderr]     Checking datafrog v2.0.1
[INFO] [stderr]    Compiling rayon-core v1.9.1
[INFO] [stderr]     Checking regex-syntax v0.6.25
[INFO] [stderr]     Checking scopeguard v1.1.0
[INFO] [stderr]     Checking glob v0.2.11
[INFO] [stderr]     Checking quick-error v1.2.3
[INFO] [stderr]     Checking cc v1.0.69
[INFO] [stderr]     Checking same-file v1.0.6
[INFO] [stderr]     Checking diff v0.1.12
[INFO] [stderr]    Compiling indexmap v1.7.0
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling memoffset v0.6.4
[INFO] [stderr]    Compiling rayon v1.5.1
[INFO] [stderr]     Checking rand_core v0.3.1
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]     Checking unicode-bidi v0.3.5
[INFO] [stderr]    Compiling num-derive v0.2.5
[INFO] [stderr]     Checking generational-arena v0.2.8
[INFO] [stderr]    Compiling parking_lot_core v0.4.0
[INFO] [stderr]     Checking rand_os v0.1.3
[INFO] [stderr]     Checking aho-corasick v0.7.18
[INFO] [stderr]     Checking num_cpus v1.13.0
[INFO] [stderr]     Checking tempfile v2.2.0
[INFO] [stderr]     Checking tinyvec v1.3.1
[INFO] [stderr]     Checking rand_hc v0.1.0
[INFO] [stderr]     Checking rand_xorshift v0.1.1
[INFO] [stderr]     Checking rand_isaac v0.1.1
[INFO] [stderr]     Checking itertools v0.7.11
[INFO] [stderr]     Checking itertools v0.8.2
[INFO] [stderr]     Checking humantime v1.3.0
[INFO] [stderr]     Checking walkdir v2.3.2
[INFO] [stderr]    Compiling rand_chacha v0.1.1
[INFO] [stderr]    Compiling rand_pcg v0.1.2
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]    Compiling quote v0.6.13
[INFO] [stderr]     Checking crossbeam-channel v0.5.1
[INFO] [stderr]     Checking unicode-normalization v0.1.19
[INFO] [stderr]     Checking crossbeam-deque v0.8.1
[INFO] [stderr]     Checking render-tree v0.1.1
[INFO] [stderr]     Checking regex v1.5.4
[INFO] [stderr]     Checking num-integer v0.1.44
[INFO] [stderr]     Checking lark-debug-with v0.1.0
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/lark-debug-with-0.1.0/src/lib.rs:6:1
[INFO] [stdout]   |
[INFO] [stdout] 6 | #![feature(box_patterns)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/lark-debug-with-0.1.0/src/lib.rs:7:1
[INFO] [stdout]   |
[INFO] [stdout] 7 | #![feature(never_type)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/lark-debug-with-0.1.0/src/lib.rs:8:1
[INFO] [stdout]   |
[INFO] [stdout] 8 | #![feature(in_band_lifetimes)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/lark-debug-with-0.1.0/src/lib.rs:9:1
[INFO] [stdout]   |
[INFO] [stdout] 9 | #![feature(specialization)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 4 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 `lark-debug-with`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "db4ac1fc63f804ad1c5f2e2c10ceed2c179a17bb128ace77ae4760397f48ddc0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "db4ac1fc63f804ad1c5f2e2c10ceed2c179a17bb128ace77ae4760397f48ddc0", kill_on_drop: false }`
[INFO] [stdout] db4ac1fc63f804ad1c5f2e2c10ceed2c179a17bb128ace77ae4760397f48ddc0
