[INFO] cloning repository https://github.com/notomo/vimonga
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/notomo/vimonga" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnotomo%2Fvimonga", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnotomo%2Fvimonga'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] f6e7142f23376d2403697bf3f5118ba64ef08450
[INFO] documenting notomo/vimonga against 1.46.0 for beta-1.47-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnotomo%2Fvimonga" "/workspace/builds/worker-4/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/notomo/vimonga 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 git repo https://github.com/notomo/vimonga
[INFO] finished tweaking git repo https://github.com/notomo/vimonga
[INFO] tweaked toml for git repo https://github.com/notomo/vimonga written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/notomo/vimonga already has a lockfile, it will not be regenerated
[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-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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] 7b0ee0961c8124d7612f41b7829d4249bc5f92a4a1bb3a83732632559a131834
[INFO] running `Command { std: "docker" "start" "-a" "7b0ee0961c8124d7612f41b7829d4249bc5f92a4a1bb3a83732632559a131834", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7b0ee0961c8124d7612f41b7829d4249bc5f92a4a1bb3a83732632559a131834", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7b0ee0961c8124d7612f41b7829d4249bc5f92a4a1bb3a83732632559a131834", kill_on_drop: false }`
[INFO] [stdout] 7b0ee0961c8124d7612f41b7829d4249bc5f92a4a1bb3a83732632559a131834
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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] 5e62d0a9d3d3c683b3c92f56b3784d2c6d8e9fb0d0a8dd1ad18e4c712b4e2cd6
[INFO] running `Command { std: "docker" "start" "-a" "5e62d0a9d3d3c683b3c92f56b3784d2c6d8e9fb0d0a8dd1ad18e4c712b4e2cd6", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.48
[INFO] [stderr]    Compiling proc-macro2 v0.4.27
[INFO] [stderr]    Compiling num-traits v0.2.6
[INFO] [stderr]    Compiling byteorder v1.3.1
[INFO] [stderr]    Compiling memchr v2.1.3
[INFO] [stderr]    Compiling serde v1.0.87
[INFO] [stderr]    Compiling ryu v0.2.7
[INFO] [stderr]    Compiling cc v1.0.29
[INFO] [stderr]     Checking ucd-util v0.1.3
[INFO] [stderr]    Compiling autocfg v0.1.2
[INFO] [stderr]    Compiling regex v0.2.11
[INFO] [stderr]     Checking utf8-ranges v1.0.2
[INFO] [stderr]     Checking indexmap v1.0.2
[INFO] [stderr]    Compiling failure_derive v0.1.5
[INFO] [stderr]     Checking rustc-demangle v0.1.13
[INFO] [stderr]     Checking try_from v0.2.2
[INFO] [stderr]     Checking hex v0.3.2
[INFO] [stderr]     Checking strsim v0.7.0
[INFO] [stderr]     Checking separator v0.3.1
[INFO] [stderr]     Checking bufstream v0.1.4
[INFO] [stderr]     Checking data-encoding v2.1.2
[INFO] [stderr]     Checking rand_core v0.3.1
[INFO] [stderr]     Checking thread_local v0.3.6
[INFO] [stderr]     Checking regex-syntax v0.5.6
[INFO] [stderr]     Checking textwrap v0.10.0
[INFO] [stderr]     Checking semver v0.8.0
[INFO] [stderr]     Checking generic-array v0.9.0
[INFO] [stderr]    Compiling backtrace v0.3.13
[INFO] [stderr]     Checking rand v0.5.6
[INFO] [stderr]     Checking time v0.1.42
[INFO] [stderr]     Checking hostname v0.1.5
[INFO] [stderr]     Checking rand v0.4.6
[INFO] [stderr]     Checking atty v0.2.11
[INFO] [stderr]     Checking digest v0.7.6
[INFO] [stderr]     Checking crypto-mac v0.6.2
[INFO] [stderr]     Checking base64 v0.9.3
[INFO] [stderr]    Compiling backtrace-sys v0.1.28
[INFO] [stderr]     Checking clap v2.32.0
[INFO] [stderr]     Checking hmac v0.6.3
[INFO] [stderr]     Checking sha2 v0.7.1
[INFO] [stderr]     Checking sha-1 v0.7.0
[INFO] [stderr]     Checking md-5 v0.7.0
[INFO] [stderr]    Compiling quote v0.6.11
[INFO] [stderr]     Checking aho-corasick v0.6.9
[INFO] [stderr]    Compiling syn v0.15.26
[INFO] [stderr]     Checking rand v0.3.23
[INFO] [stderr]     Checking num-integer v0.1.39
[INFO] [stderr]     Checking chrono v0.4.6
[INFO] [stderr]     Checking pbkdf2 v0.2.3
[INFO] [stderr]     Checking scan_fmt v0.1.3
[INFO] [stderr]    Compiling synstructure v0.10.1
[INFO] [stderr]     Checking serde_json v1.0.38
[INFO] [stderr]    Compiling serde_derive v1.0.87
[INFO] [stderr]     Checking bson v0.13.0
[INFO] [stderr]     Checking failure v0.1.5
[INFO] [stderr]     Checking textnonce v0.6.4
[INFO] [stderr]     Checking mongodb v0.3.12
[INFO] [stderr]  Documenting vimonga v0.0.1 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/main.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(slice_patterns)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 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 document `vimonga`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type bin --crate-name vimonga src/main.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi --document-private-items -L dependency=/opt/rustwide/target/debug/deps --extern bson=/opt/rustwide/target/debug/deps/libbson-3cda73ed398cddf7.rmeta --extern clap=/opt/rustwide/target/debug/deps/libclap-cdb2f5af53fff95e.rmeta --extern failure=/opt/rustwide/target/debug/deps/libfailure-cb9710595f5d99a8.rmeta --extern mongodb=/opt/rustwide/target/debug/deps/libmongodb-27a1aac5d5f19d6e.rmeta --extern serde=/opt/rustwide/target/debug/deps/libserde-a6093196acd8d5dc.rmeta --extern serde_derive=/opt/rustwide/target/debug/deps/libserde_derive-40cca0fb41dd962f.so --extern serde_json=/opt/rustwide/target/debug/deps/libserde_json-25d96ff9f1af04e0.rmeta --cap-lints=warn` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "5e62d0a9d3d3c683b3c92f56b3784d2c6d8e9fb0d0a8dd1ad18e4c712b4e2cd6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5e62d0a9d3d3c683b3c92f56b3784d2c6d8e9fb0d0a8dd1ad18e4c712b4e2cd6", kill_on_drop: false }`
[INFO] [stdout] 5e62d0a9d3d3c683b3c92f56b3784d2c6d8e9fb0d0a8dd1ad18e4c712b4e2cd6