[INFO] cloning repository https://github.com/adrien-zinger/Diff
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/adrien-zinger/Diff" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fadrien-zinger%2FDiff", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fadrien-zinger%2FDiff'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 11ae40ed6b2c9440ffa7131d7f03f9c75d69620a
[INFO] documenting adrien-zinger/Diff 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%2Fadrien-zinger%2FDiff" "/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/adrien-zinger/Diff 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/adrien-zinger/Diff
[INFO] finished tweaking git repo https://github.com/adrien-zinger/Diff
[INFO] tweaked toml for git repo https://github.com/adrien-zinger/Diff written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/adrien-zinger/Diff 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 snap v1.0.5
[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" "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] fca3eed633216097479478bc3144563385bc353831b85185de0c41958ba1ff16
[INFO] running `Command { std: "docker" "start" "-a" "fca3eed633216097479478bc3144563385bc353831b85185de0c41958ba1ff16", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "fca3eed633216097479478bc3144563385bc353831b85185de0c41958ba1ff16", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fca3eed633216097479478bc3144563385bc353831b85185de0c41958ba1ff16", kill_on_drop: false }`
[INFO] [stdout] fca3eed633216097479478bc3144563385bc353831b85185de0c41958ba1ff16
[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" "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] 9482cb2a75bb9460b9849650b306d22bc83ab377250b9a6294010f38b2dd4a0c
[INFO] running `Command { std: "docker" "start" "-a" "9482cb2a75bb9460b9849650b306d22bc83ab377250b9a6294010f38b2dd4a0c", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.29
[INFO] [stderr]    Compiling unicode-xid v0.2.2
[INFO] [stderr]    Compiling syn v1.0.76
[INFO] [stderr]    Compiling unicode-segmentation v1.8.0
[INFO] [stderr]    Compiling snap v1.0.5
[INFO] [stderr]     Checking bitflags v1.3.2
[INFO] [stderr]     Checking textwrap v0.11.0
[INFO] [stderr]     Checking clap v2.33.3
[INFO] [stderr]    Compiling heck v0.3.3
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]    Compiling proc-macro-error-attr v1.0.4
[INFO] [stderr]    Compiling proc-macro-error v1.0.4
[INFO] [stderr]    Compiling structopt-derive v0.4.16
[INFO] [stderr]     Checking structopt v0.3.23
[INFO] [stderr]  Documenting diff_tool 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(test)]
[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 `diff_tool`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type bin --crate-name diff_tool src/main.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=e0bd9f69c9a8b84d -L dependency=/opt/rustwide/target/debug/deps --extern snap=/opt/rustwide/target/debug/deps/libsnap-640537bedda3ecba.rmeta --extern structopt=/opt/rustwide/target/debug/deps/libstructopt-248bae7f193790ac.rmeta --cap-lints=warn --crate-version 0.1.0` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "9482cb2a75bb9460b9849650b306d22bc83ab377250b9a6294010f38b2dd4a0c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9482cb2a75bb9460b9849650b306d22bc83ab377250b9a6294010f38b2dd4a0c", kill_on_drop: false }`
[INFO] [stdout] 9482cb2a75bb9460b9849650b306d22bc83ab377250b9a6294010f38b2dd4a0c