[INFO] fetching crate skip 0.0.0...
[INFO] documenting skip-0.0.0 against 1.61.0 for beta-1.62-rustdoc-1
[INFO] extracting crate skip 0.0.0 into /workspace/builds/worker-16/source
[INFO] validating manifest of crates.io crate skip 0.0.0 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 skip 0.0.0
[INFO] finished tweaking crates.io crate skip 0.0.0
[INFO] tweaked toml for crates.io crate skip 0.0.0 written to /workspace/builds/worker-16/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]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-16/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-16/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] ed0b2bf0097b88fb1a119ccc2495097ebf32e81d07ca00d99ff7bae42518a240
[INFO] running `Command { std: "docker" "start" "-a" "ed0b2bf0097b88fb1a119ccc2495097ebf32e81d07ca00d99ff7bae42518a240", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ed0b2bf0097b88fb1a119ccc2495097ebf32e81d07ca00d99ff7bae42518a240", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ed0b2bf0097b88fb1a119ccc2495097ebf32e81d07ca00d99ff7bae42518a240", kill_on_drop: false }`
[INFO] [stdout] ed0b2bf0097b88fb1a119ccc2495097ebf32e81d07ca00d99ff7bae42518a240
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-16/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-16/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] 1d975f27eb8495fa0741a51ef1807cba646e9d407bf36e83a9dd7644b5ad455d
[INFO] running `Command { std: "docker" "start" "-a" "1d975f27eb8495fa0741a51ef1807cba646e9d407bf36e83a9dd7644b5ad455d", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking rand_core v0.4.2
[INFO] [stderr]    Compiling libc v0.2.126
[INFO] [stderr]    Compiling autocfg v0.1.8
[INFO] [stderr]     Checking rand_core v0.3.1
[INFO] [stderr]     Checking rand_jitter v0.1.4
[INFO] [stderr]    Compiling rand_pcg v0.1.2
[INFO] [stderr]    Compiling rand_chacha v0.1.1
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]     Checking rand_xorshift v0.1.1
[INFO] [stderr]     Checking rand_isaac v0.1.1
[INFO] [stderr]     Checking rand_hc v0.1.0
[INFO] [stderr]     Checking rand_os v0.1.3
[INFO] [stderr]  Documenting skip v0.0.0 (/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(box_into_raw_non_null)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0635]: unknown feature `box_into_raw_non_null`
[INFO] [stdout]  --> src/lib.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(box_into_raw_non_null)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0554, E0635.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not document `skip`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name skip src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=3ae45c692650eda8 -L dependency=/opt/rustwide/target/debug/deps --extern rand=/opt/rustwide/target/debug/deps/librand-6d8e3b6d7ebfb3eb.rmeta --cap-lints=warn --crate-version 0.0.0` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "1d975f27eb8495fa0741a51ef1807cba646e9d407bf36e83a9dd7644b5ad455d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1d975f27eb8495fa0741a51ef1807cba646e9d407bf36e83a9dd7644b5ad455d", kill_on_drop: false }`
[INFO] [stdout] 1d975f27eb8495fa0741a51ef1807cba646e9d407bf36e83a9dd7644b5ad455d