[INFO] fetching crate lark 0.1.0...
[INFO] documenting lark-0.1.0 against 1.46.0 for beta-1.47-rustdoc-1
[INFO] extracting crate lark 0.1.0 into /workspace/builds/worker-7/source
[INFO] validating manifest of crates.io crate lark 0.1.0 on toolchain 1.46.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate lark 0.1.0
[INFO] finished tweaking crates.io crate lark 0.1.0
[INFO] tweaked toml for crates.io crate lark 0.1.0 written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "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" "+1.46.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.46.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] f892c313f1b53ae06a8ff042658209b243c634908007efe898d7e68d3f1cd814
[INFO] running `Command { std: "docker" "start" "-a" "f892c313f1b53ae06a8ff042658209b243c634908007efe898d7e68d3f1cd814", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f892c313f1b53ae06a8ff042658209b243c634908007efe898d7e68d3f1cd814", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f892c313f1b53ae06a8ff042658209b243c634908007efe898d7e68d3f1cd814", kill_on_drop: false }`
[INFO] [stdout] f892c313f1b53ae06a8ff042658209b243c634908007efe898d7e68d3f1cd814
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.46.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] db635ddec6346673832c4db8dd1b67ff27e59c550a903bab5d82383fe61d5a0a
[INFO] running `Command { std: "docker" "start" "-a" "db635ddec6346673832c4db8dd1b67ff27e59c550a903bab5d82383fe61d5a0a", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v1.0.1
[INFO] [stderr]    Compiling libc v0.2.76
[INFO] [stderr]    Compiling autocfg v0.1.7
[INFO] [stderr]    Compiling proc-macro2 v1.0.19
[INFO] [stderr]     Checking rand_core v0.4.2
[INFO] [stderr]    Compiling unicode-xid v0.2.1
[INFO] [stderr]    Compiling syn v1.0.39
[INFO] [stderr]    Compiling serde_derive v1.0.115
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]    Compiling semver-parser v0.7.0
[INFO] [stderr]    Compiling unicode-xid v0.1.0
[INFO] [stderr]    Compiling maybe-uninit v2.0.0
[INFO] [stderr]    Compiling serde v1.0.115
[INFO] [stderr]     Checking tinyvec v0.3.4
[INFO] [stderr]     Checking matches v0.1.8
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]     Checking cfg-if v0.1.10
[INFO] [stderr]    Compiling ryu v1.0.5
[INFO] [stderr]     Checking stable_deref_trait v1.2.0
[INFO] [stderr]    Compiling log v0.4.11
[INFO] [stderr]    Compiling serde_json v1.0.57
[INFO] [stderr]    Compiling num-derive v0.2.5
[INFO] [stderr]     Checking percent-encoding v1.0.1
[INFO] [stderr]     Checking scopeguard v0.3.3
[INFO] [stderr]    Compiling bitflags v1.2.1
[INFO] [stderr]     Checking rustc-hash v1.1.0
[INFO] [stderr]     Checking itoa v0.4.6
[INFO] [stderr]     Checking either v1.6.0
[INFO] [stderr]     Checking termcolor v1.1.0
[INFO] [stderr]    Compiling memchr v2.3.3
[INFO] [stderr]     Checking datafrog v2.0.1
[INFO] [stderr]     Checking lazy_static v1.4.0
[INFO] [stderr]     Checking regex-syntax v0.6.18
[INFO] [stderr]     Checking cc v1.0.59
[INFO] [stderr]     Checking glob v0.2.11
[INFO] [stderr]     Checking rand_core v0.3.1
[INFO] [stderr]     Checking rand_jitter v0.1.4
[INFO] [stderr]     Checking unicode-bidi v0.3.4
[INFO] [stderr]    Compiling semver v0.9.0
[INFO] [stderr]     Checking generational-arena v0.2.8
[INFO] [stderr]     Checking owning_ref v0.4.1
[INFO] [stderr]     Checking unicode-normalization v0.1.13
[INFO] [stderr]     Checking itertools v0.7.11
[INFO] [stderr]     Checking itertools v0.8.2
[INFO] [stderr]     Checking thread_local v1.0.1
[INFO] [stderr]     Checking rand_xorshift v0.1.1
[INFO] [stderr]     Checking rand_isaac v0.1.1
[INFO] [stderr]     Checking rand_hc v0.1.0
[INFO] [stderr]     Checking lock_api v0.1.5
[INFO] [stderr]    Compiling rustc_version v0.2.3
[INFO] [stderr]     Checking smallvec v0.6.13
[INFO] [stderr]    Compiling rand_pcg v0.1.2
[INFO] [stderr]    Compiling rand_chacha v0.1.1
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]     Checking aho-corasick v0.7.13
[INFO] [stderr]    Compiling quote v0.6.13
[INFO] [stderr]     Checking render-tree v0.1.1
[INFO] [stderr]     Checking rand_os v0.1.3
[INFO] [stderr]     Checking rand v0.4.6
[INFO] [stderr]     Checking time v0.1.44
[INFO] [stderr]     Checking idna v0.1.5
[INFO] [stderr]    Compiling quote v1.0.7
[INFO] [stderr]    Compiling hashbrown v0.8.2
[INFO] [stderr]    Compiling indexmap v1.5.2
[INFO] [stderr]    Compiling num-traits v0.2.12
[INFO] [stderr]    Compiling num-integer v0.1.43
[INFO] [stderr]     Checking url v1.7.2
[INFO] [stderr]     Checking rand v0.3.23
[INFO] [stderr]     Checking regex v1.3.9
[INFO] [stderr]     Checking tempfile v2.2.0
[INFO] [stderr]    Compiling parking_lot_core v0.4.0
[INFO] [stderr]     Checking parking_lot v0.7.1
[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" "db635ddec6346673832c4db8dd1b67ff27e59c550a903bab5d82383fe61d5a0a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "db635ddec6346673832c4db8dd1b67ff27e59c550a903bab5d82383fe61d5a0a", kill_on_drop: false }`
[INFO] [stdout] db635ddec6346673832c4db8dd1b67ff27e59c550a903bab5d82383fe61d5a0a