[INFO] fetching crate guff-matrix 0.1.12...
[INFO] documenting guff-matrix-0.1.12 against 1.54.0 for beta-1.55-rustdoc-1
[INFO] extracting crate guff-matrix 0.1.12 into /workspace/builds/worker-8/source
[INFO] validating manifest of crates.io crate guff-matrix 0.1.12 on toolchain 1.54.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate guff-matrix 0.1.12
[INFO] finished tweaking crates.io crate guff-matrix 0.1.12
[INFO] tweaked toml for crates.io crate guff-matrix 0.1.12 written to /workspace/builds/worker-8/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "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-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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 93f1a0859e4b46f452de21d630041c1f6e759559c7162a743e5f76ea50b7ff53
[INFO] running `Command { std: "docker" "start" "-a" "93f1a0859e4b46f452de21d630041c1f6e759559c7162a743e5f76ea50b7ff53", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "93f1a0859e4b46f452de21d630041c1f6e759559c7162a743e5f76ea50b7ff53", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "93f1a0859e4b46f452de21d630041c1f6e759559c7162a743e5f76ea50b7ff53", kill_on_drop: false }`
[INFO] [stdout] 93f1a0859e4b46f452de21d630041c1f6e759559c7162a743e5f76ea50b7ff53
[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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 532d2156d8be844d8b471cd844fbeb2f13617b40cd7dcfb7e24512ba05665fe7
[INFO] running `Command { std: "docker" "start" "-a" "532d2156d8be844d8b471cd844fbeb2f13617b40cd7dcfb7e24512ba05665fe7", kill_on_drop: false }`
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling num-integer v0.1.44
[INFO] [stderr]    Compiling num-bigint v0.4.0
[INFO] [stderr]    Compiling num-iter v0.1.42
[INFO] [stderr]    Compiling num-rational v0.4.0
[INFO] [stderr]     Checking num-complex v0.4.0
[INFO] [stderr]     Checking num v0.4.0
[INFO] [stderr]     Checking guff v0.1.7
[INFO] [stderr]  Documenting guff-matrix v0.1.12 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:53:1
[INFO] [stdout]    |
[INFO] [stdout] 53 | #![feature(stdsimd)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 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 `guff-matrix`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name guff_matrix src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi --document-private-items -L dependency=/opt/rustwide/target/debug/deps --extern guff=/opt/rustwide/target/debug/deps/libguff-488ce3b630987398.rmeta --cap-lints=warn --crate-version 0.1.12` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "532d2156d8be844d8b471cd844fbeb2f13617b40cd7dcfb7e24512ba05665fe7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "532d2156d8be844d8b471cd844fbeb2f13617b40cd7dcfb7e24512ba05665fe7", kill_on_drop: false }`
[INFO] [stdout] 532d2156d8be844d8b471cd844fbeb2f13617b40cd7dcfb7e24512ba05665fe7
