[INFO] fetching crate lark-type-check 0.1.0...
[INFO] documenting lark-type-check-0.1.0 against 1.54.0 for beta-1.55-rustdoc-1
[INFO] extracting crate lark-type-check 0.1.0 into /workspace/builds/worker-49/source
[INFO] validating manifest of crates.io crate lark-type-check 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-type-check 0.1.0
[INFO] finished tweaking crates.io crate lark-type-check 0.1.0
[INFO] tweaked toml for crates.io crate lark-type-check 0.1.0 written to /workspace/builds/worker-49/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-49/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-49/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] 3f6984a4e9ce3a9c8285dba1845e12891168e1fd58d133e42a949b68b6db04ef
[INFO] running `Command { std: "docker" "start" "-a" "3f6984a4e9ce3a9c8285dba1845e12891168e1fd58d133e42a949b68b6db04ef", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3f6984a4e9ce3a9c8285dba1845e12891168e1fd58d133e42a949b68b6db04ef", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3f6984a4e9ce3a9c8285dba1845e12891168e1fd58d133e42a949b68b6db04ef", kill_on_drop: false }`
[INFO] [stdout] 3f6984a4e9ce3a9c8285dba1845e12891168e1fd58d133e42a949b68b6db04ef
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-49/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-49/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] 5495069eb6da2ce275a43af6d5b80ea454892ec6429204e8e76743acf1fa10be
[INFO] running `Command { std: "docker" "start" "-a" "5495069eb6da2ce275a43af6d5b80ea454892ec6429204e8e76743acf1fa10be", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling autocfg v0.1.7
[INFO] [stderr]     Checking rand_core v0.4.2
[INFO] [stderr]    Compiling semver-parser v0.7.0
[INFO] [stderr]     Checking stable_deref_trait v1.2.0
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]     Checking scopeguard v0.3.3
[INFO] [stderr]     Checking rustc-hash v1.1.0
[INFO] [stderr]     Checking either v1.6.1
[INFO] [stderr]    Compiling num-derive v0.2.5
[INFO] [stderr]     Checking percent-encoding v1.0.1
[INFO] [stderr]     Checking termcolor v1.1.2
[INFO] [stderr]     Checking itoa v0.4.7
[INFO] [stderr]     Checking unicode-xid v0.1.0
[INFO] [stderr]     Checking datafrog v2.0.1
[INFO] [stderr]     Checking generational-arena v0.2.8
[INFO] [stderr]     Checking smallvec v0.6.14
[INFO] [stderr]     Checking idna v0.1.5
[INFO] [stderr]     Checking lark-debug-with v0.1.0
[INFO] [stderr]    Compiling derive-new v0.5.9
[INFO] [stderr]     Checking itertools v0.7.11
[INFO] [stderr]     Checking itertools v0.8.2
[INFO] [stderr]     Checking owning_ref v0.4.1
[INFO] [stderr]     Checking serde_json v1.0.66
[INFO] [stderr]     Checking rand_core v0.3.1
[INFO] [stderr]     Checking rand_os v0.1.3
[INFO] [stderr]     Checking rand_jitter v0.1.4
[INFO] [stderr]    Compiling semver v0.9.0
[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] [stderr]     Checking lock_api v0.1.5
[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" "5495069eb6da2ce275a43af6d5b80ea454892ec6429204e8e76743acf1fa10be", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5495069eb6da2ce275a43af6d5b80ea454892ec6429204e8e76743acf1fa10be", kill_on_drop: false }`
[INFO] [stdout] 5495069eb6da2ce275a43af6d5b80ea454892ec6429204e8e76743acf1fa10be
