[INFO] fetching crate changebase 0.1.0...
[INFO] documenting changebase-0.1.0 against 1.61.0 for beta-1.62-rustdoc-1
[INFO] extracting crate changebase 0.1.0 into /workspace/builds/worker-47/source
[INFO] validating manifest of crates.io crate changebase 0.1.0 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 crates.io crate changebase 0.1.0
[INFO] finished tweaking crates.io crate changebase 0.1.0
[INFO] tweaked toml for crates.io crate changebase 0.1.0 written to /workspace/builds/worker-47/source/Cargo.toml
[INFO] crate crates.io crate changebase 0.1.0 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]  Downloading crates ...
[INFO] [stderr]   Downloaded structopt-derive v0.4.16
[INFO] [stderr]   Downloaded structopt v0.3.23
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-47/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-47/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] f7f7f34e1b624c47c5569a7dee56e0dd4038e4d43434e55fb724e16007fc02b2
[INFO] running `Command { std: "docker" "start" "-a" "f7f7f34e1b624c47c5569a7dee56e0dd4038e4d43434e55fb724e16007fc02b2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f7f7f34e1b624c47c5569a7dee56e0dd4038e4d43434e55fb724e16007fc02b2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f7f7f34e1b624c47c5569a7dee56e0dd4038e4d43434e55fb724e16007fc02b2", kill_on_drop: false }`
[INFO] [stdout] f7f7f34e1b624c47c5569a7dee56e0dd4038e4d43434e55fb724e16007fc02b2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-47/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-47/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] 7e551e59e1a3d722e37950f6d21b8c84ea242f725c53c2658371a9663ad95b41
[INFO] running `Command { std: "docker" "start" "-a" "7e551e59e1a3d722e37950f6d21b8c84ea242f725c53c2658371a9663ad95b41", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v1.1.0
[INFO] [stderr]    Compiling proc-macro2 v1.0.30
[INFO] [stderr]    Compiling unicode-xid v0.2.2
[INFO] [stderr]    Compiling version_check v0.9.3
[INFO] [stderr]    Compiling syn v1.0.80
[INFO] [stderr]    Compiling libc v0.2.103
[INFO] [stderr]    Compiling unicode-segmentation v1.8.0
[INFO] [stderr]     Checking unicode-width v0.1.9
[INFO] [stderr]    Compiling anyhow v1.0.44
[INFO] [stderr]     Checking bitflags v1.3.2
[INFO] [stderr]     Checking vec_map v0.8.2
[INFO] [stderr]     Checking textwrap v0.11.0
[INFO] [stderr]    Compiling proc-macro-error-attr v1.0.4
[INFO] [stderr]    Compiling proc-macro-error v1.0.4
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling num-integer v0.1.44
[INFO] [stderr]    Compiling num-bigint v0.4.3
[INFO] [stderr]    Compiling num-iter v0.1.42
[INFO] [stderr]    Compiling num-rational v0.4.0
[INFO] [stderr]    Compiling heck v0.3.3
[INFO] [stderr]    Compiling quote v1.0.10
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking clap v2.33.3
[INFO] [stderr]     Checking num-complex v0.4.0
[INFO] [stderr]     Checking num v0.4.0
[INFO] [stderr]    Compiling structopt-derive v0.4.16
[INFO] [stderr]    Compiling thiserror-impl v1.0.30
[INFO] [stderr]     Checking structopt v0.3.23
[INFO] [stderr]     Checking thiserror v1.0.30
[INFO] [stderr]  Documenting changebase 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(result_option_inspect)]
[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 `changebase`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type bin --crate-name changebase src/main.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=eb77040d646a82b6 -L dependency=/opt/rustwide/target/debug/deps --extern anyhow=/opt/rustwide/target/debug/deps/libanyhow-e2f1045db6186d31.rmeta --extern clap=/opt/rustwide/target/debug/deps/libclap-8cdcb0993aeb483c.rmeta --extern num=/opt/rustwide/target/debug/deps/libnum-e6fe91b9e9d369c9.rmeta --extern structopt=/opt/rustwide/target/debug/deps/libstructopt-8b3b1d661d6a5e74.rmeta --extern thiserror=/opt/rustwide/target/debug/deps/libthiserror-a5345a0d5078249b.rmeta --cap-lints=warn --crate-version 0.1.0` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "7e551e59e1a3d722e37950f6d21b8c84ea242f725c53c2658371a9663ad95b41", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7e551e59e1a3d722e37950f6d21b8c84ea242f725c53c2658371a9663ad95b41", kill_on_drop: false }`
[INFO] [stdout] 7e551e59e1a3d722e37950f6d21b8c84ea242f725c53c2658371a9663ad95b41