[INFO] fetching crate pflag 0.6.2...
[INFO] documenting pflag-0.6.2 against 1.61.0 for beta-1.62-rustdoc-1
[INFO] extracting crate pflag 0.6.2 into /workspace/builds/worker-34/source
[INFO] validating manifest of crates.io crate pflag 0.6.2 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 pflag 0.6.2
[INFO] finished tweaking crates.io crate pflag 0.6.2
[INFO] tweaked toml for crates.io crate pflag 0.6.2 written to /workspace/builds/worker-34/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[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 concat-idents v1.1.3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-34/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-34/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] e0fbd9c647727cf0881b3df8121c71cdf2a5ff1d9981255b6f757b84c3fa21c0
[INFO] running `Command { std: "docker" "start" "-a" "e0fbd9c647727cf0881b3df8121c71cdf2a5ff1d9981255b6f757b84c3fa21c0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e0fbd9c647727cf0881b3df8121c71cdf2a5ff1d9981255b6f757b84c3fa21c0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e0fbd9c647727cf0881b3df8121c71cdf2a5ff1d9981255b6f757b84c3fa21c0", kill_on_drop: false }`
[INFO] [stdout] e0fbd9c647727cf0881b3df8121c71cdf2a5ff1d9981255b6f757b84c3fa21c0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-34/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-34/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] d249f6ce39ced05a8bc0593b157d9ac6e2e85b850d343de352df228156bac537
[INFO] running `Command { std: "docker" "start" "-a" "d249f6ce39ced05a8bc0593b157d9ac6e2e85b850d343de352df228156bac537", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.39
[INFO] [stderr]    Compiling unicode-ident v1.0.0
[INFO] [stderr]    Compiling syn v1.0.95
[INFO] [stderr]    Compiling paste v1.0.7
[INFO] [stderr]    Compiling quote v1.0.18
[INFO] [stderr]    Compiling concat-idents v1.1.3
[INFO] [stderr]  Documenting pflag v0.6.2 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:37:12
[INFO] [stdout]    |
[INFO] [stdout] 37 | #![feature(const_type_id)]
[INFO] [stdout]    |            ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:38:12
[INFO] [stdout]    |
[INFO] [stdout] 38 | #![feature(type_name_of_val)]
[INFO] [stdout]    |            ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:39:12
[INFO] [stdout]    |
[INFO] [stdout] 39 | #![feature(test)]
[INFO] [stdout]    |            ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:40:12
[INFO] [stdout]    |
[INFO] [stdout] 40 | #![feature(duration_constants)]
[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 document `pflag`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name pflag src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=4ed3bade3514d55a -L dependency=/opt/rustwide/target/debug/deps --extern concat_idents=/opt/rustwide/target/debug/deps/libconcat_idents-7fd6676be042c905.so --extern paste=/opt/rustwide/target/debug/deps/libpaste-bd6d0284544a8d29.so --cap-lints=warn --crate-version 0.6.2` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "d249f6ce39ced05a8bc0593b157d9ac6e2e85b850d343de352df228156bac537", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d249f6ce39ced05a8bc0593b157d9ac6e2e85b850d343de352df228156bac537", kill_on_drop: false }`
[INFO] [stdout] d249f6ce39ced05a8bc0593b157d9ac6e2e85b850d343de352df228156bac537