[INFO] cloning repository https://github.com/openstax-poland/gitpub
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/openstax-poland/gitpub" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fopenstax-poland%2Fgitpub", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fopenstax-poland%2Fgitpub'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 44c3a7db0d0db3d1f94fab8bb386ecc8c9204e83
[INFO] documenting openstax-poland/gitpub against 1.61.0 for beta-1.62-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fopenstax-poland%2Fgitpub" "/workspace/builds/worker-27/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-27/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/openstax-poland/gitpub on toolchain 1.61.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/openstax-poland/gitpub
[INFO] finished tweaking git repo https://github.com/openstax-poland/gitpub
[INFO] tweaked toml for git repo https://github.com/openstax-poland/gitpub written to /workspace/builds/worker-27/source/Cargo.toml
[INFO] crate git repo https://github.com/openstax-poland/gitpub already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "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 argh_shared v0.1.6
[INFO] [stderr]   Downloaded argh v0.1.6
[INFO] [stderr]   Downloaded git2 v0.13.23
[INFO] [stderr]   Downloaded argh_derive v0.1.6
[INFO] [stderr]   Downloaded libgit2-sys v0.12.24+1.3.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-27/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-27/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:d190cb871061d98bc6d0581d85cb2ecb09a0f8a142ba5463de30be9999fc3251" "/opt/rustwide/cargo-home/bin/cargo" "+1.61.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 71f55c594f0b54903916f98b1c47e5d99375375909f8bbe06d05890fd60c0b40
[INFO] running `Command { std: "docker" "start" "-a" "71f55c594f0b54903916f98b1c47e5d99375375909f8bbe06d05890fd60c0b40", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "71f55c594f0b54903916f98b1c47e5d99375375909f8bbe06d05890fd60c0b40", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "71f55c594f0b54903916f98b1c47e5d99375375909f8bbe06d05890fd60c0b40", kill_on_drop: false }`
[INFO] [stdout] 71f55c594f0b54903916f98b1c47e5d99375375909f8bbe06d05890fd60c0b40
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-27/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-27/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:d190cb871061d98bc6d0581d85cb2ecb09a0f8a142ba5463de30be9999fc3251" "/opt/rustwide/cargo-home/bin/cargo" "+1.61.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 9a169e000b37c792cefd9577840d83c3dcae755a4ecbdb2bb5b8438d6d0a80df
[INFO] running `Command { std: "docker" "start" "-a" "9a169e000b37c792cefd9577840d83c3dcae755a4ecbdb2bb5b8438d6d0a80df", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.104
[INFO] [stderr]    Compiling pkg-config v0.3.20
[INFO] [stderr]    Compiling proc-macro2 v1.0.30
[INFO] [stderr]    Compiling syn v1.0.80
[INFO] [stderr]     Checking tinyvec_macros v0.1.0
[INFO] [stderr]     Checking matches v0.1.9
[INFO] [stderr]    Compiling unicode-segmentation v1.8.0
[INFO] [stderr]     Checking unicode-bidi v0.3.7
[INFO] [stderr]     Checking adler v1.0.2
[INFO] [stderr]    Compiling argh_shared v0.1.6
[INFO] [stderr]    Compiling anyhow v1.0.44
[INFO] [stderr]     Checking numtoa v0.1.0
[INFO] [stderr]     Checking humantime v2.1.0
[INFO] [stderr]     Checking termcolor v1.1.2
[INFO] [stderr]     Checking json v0.12.4
[INFO] [stderr]    Compiling miniz_oxide v0.4.4
[INFO] [stderr]     Checking tinyvec v1.5.0
[INFO] [stderr]     Checking form_urlencoded v1.0.1
[INFO] [stderr]    Compiling heck v0.3.3
[INFO] [stderr]    Compiling quote v1.0.10
[INFO] [stderr]     Checking unicode-normalization v0.1.19
[INFO] [stderr]    Compiling jobserver v0.1.24
[INFO] [stderr]     Checking filetime v0.2.15
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking xattr v0.2.2
[INFO] [stderr]     Checking termion v1.5.6
[INFO] [stderr]     Checking flate2 v1.0.22
[INFO] [stderr]     Checking env_logger v0.9.0
[INFO] [stderr]    Compiling cc v1.0.71
[INFO] [stderr]     Checking tar v0.4.37
[INFO] [stderr]     Checking idna v0.2.3
[INFO] [stderr]     Checking url v2.2.2
[INFO] [stderr]    Compiling openssl-sys v0.9.67
[INFO] [stderr]    Compiling libz-sys v1.1.3
[INFO] [stderr]    Compiling libssh2-sys v0.2.23
[INFO] [stderr]    Compiling libgit2-sys v0.12.24+1.3.0
[INFO] [stderr]    Compiling argh_derive v0.1.6
[INFO] [stderr]    Compiling ctor v0.1.21
[INFO] [stderr]     Checking argh v0.1.6
[INFO] [stderr]     Checking git2 v0.13.23
[INFO] [stderr]  Documenting gitpub v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/main.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(map_first_last)]
[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 document `gitpub`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type bin --crate-name gitpub src/main.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=020760c17758403e -L dependency=/opt/rustwide/target/debug/deps --extern anyhow=/opt/rustwide/target/debug/deps/libanyhow-e2f1045db6186d31.rmeta --extern argh=/opt/rustwide/target/debug/deps/libargh-90f6a7bef783205c.rmeta --extern ctor=/opt/rustwide/target/debug/deps/libctor-7c57815d3e064a8c.so --extern env_logger=/opt/rustwide/target/debug/deps/libenv_logger-c5a5508e41d83b50.rmeta --extern flate2=/opt/rustwide/target/debug/deps/libflate2-6a2c4b13da1df9be.rmeta --extern git2=/opt/rustwide/target/debug/deps/libgit2-7c675d8e97324537.rmeta --extern json=/opt/rustwide/target/debug/deps/libjson-d3b01422cf953791.rmeta --extern log=/opt/rustwide/target/debug/deps/liblog-1e3c371ab90a7930.rmeta --extern tar=/opt/rustwide/target/debug/deps/libtar-59b021a194c03dd6.rmeta --extern termion=/opt/rustwide/target/debug/deps/libtermion-7a8d2e7c1bf9b500.rmeta --cap-lints=warn --crate-version 0.1.0` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "9a169e000b37c792cefd9577840d83c3dcae755a4ecbdb2bb5b8438d6d0a80df", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9a169e000b37c792cefd9577840d83c3dcae755a4ecbdb2bb5b8438d6d0a80df", kill_on_drop: false }`
[INFO] [stdout] 9a169e000b37c792cefd9577840d83c3dcae755a4ecbdb2bb5b8438d6d0a80df