[INFO] fetching crate second-stack 0.2.1...
[INFO] documenting second-stack-0.2.1 against 1.61.0 for beta-1.62-rustdoc-1
[INFO] extracting crate second-stack 0.2.1 into /workspace/builds/worker-8/source
[INFO] validating manifest of crates.io crate second-stack 0.2.1 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 second-stack 0.2.1
[INFO] finished tweaking crates.io crate second-stack 0.2.1
[INFO] tweaked toml for crates.io crate second-stack 0.2.1 written to /workspace/builds/worker-8/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 testdrop v0.1.2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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] ec15af522fe103b139591bf4062f1e7feb08b30e5f1c22cd85572af2abff6178
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "ec15af522fe103b139591bf4062f1e7feb08b30e5f1c22cd85572af2abff6178", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ec15af522fe103b139591bf4062f1e7feb08b30e5f1c22cd85572af2abff6178", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ec15af522fe103b139591bf4062f1e7feb08b30e5f1c22cd85572af2abff6178", kill_on_drop: false }`
[INFO] [stdout] ec15af522fe103b139591bf4062f1e7feb08b30e5f1c22cd85572af2abff6178
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 89e06ee3cdf798adf4ea9e0454c90478e665744fbd01aed58e30fb8fd245e027
[INFO] running `Command { std: "docker" "start" "-a" "89e06ee3cdf798adf4ea9e0454c90478e665744fbd01aed58e30fb8fd245e027", kill_on_drop: false }`
[INFO] [stderr]  Documenting second-stack v0.2.1 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(allocator_api, alloc_layout_extra, ptr_offset_from)]
[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:1:27
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(allocator_api, alloc_layout_extra, ptr_offset_from)]
[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:1:47
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(allocator_api, alloc_layout_extra, ptr_offset_from)]
[INFO] [stdout]   |                                               ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this URL is not a hyperlink
[INFO] [stdout]   --> src/lib.rs:21:5
[INFO] [stdout]    |
[INFO] [stdout] 21 | /// https://github.com/rust-lang/rust/issues/62420
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use an automatic link instead: `<https://github.com/rust-lang/rust/issues/62420>`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(rustdoc::bare_urls)]` on by default
[INFO] [stdout]    = note: bare URLs are not automatically turned into clickable links
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 3 previous errors; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not document `second-stack`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name second_stack src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=75863fc495384ae8 -L dependency=/opt/rustwide/target/debug/deps --cap-lints=warn --crate-version 0.2.1` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "89e06ee3cdf798adf4ea9e0454c90478e665744fbd01aed58e30fb8fd245e027", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "89e06ee3cdf798adf4ea9e0454c90478e665744fbd01aed58e30fb8fd245e027", kill_on_drop: false }`
[INFO] [stdout] 89e06ee3cdf798adf4ea9e0454c90478e665744fbd01aed58e30fb8fd245e027