[INFO] fetching crate impulse_response 0.6.1...
[INFO] documenting impulse_response-0.6.1 against 1.54.0 for beta-1.55-rustdoc-1
[INFO] extracting crate impulse_response 0.6.1 into /workspace/builds/worker-2/source
[INFO] validating manifest of crates.io crate impulse_response 0.6.1 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 impulse_response 0.6.1
[INFO] finished tweaking crates.io crate impulse_response 0.6.1
[INFO] tweaked toml for crates.io crate impulse_response 0.6.1 written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] crate crates.io crate impulse_response 0.6.1 already has a lockfile, it will not be regenerated
[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-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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] f109f7cbb28ea10210c8aabc53fe28b1fa982567828e4adce236c870966c5a58
[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" "f109f7cbb28ea10210c8aabc53fe28b1fa982567828e4adce236c870966c5a58", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f109f7cbb28ea10210c8aabc53fe28b1fa982567828e4adce236c870966c5a58", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f109f7cbb28ea10210c8aabc53fe28b1fa982567828e4adce236c870966c5a58", kill_on_drop: false }`
[INFO] [stdout] f109f7cbb28ea10210c8aabc53fe28b1fa982567828e4adce236c870966c5a58
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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] 9ca78934967a6f869747650d85c05a00f3fc6ced6b96f8d0a1e5137b71ea2bdb
[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" "9ca78934967a6f869747650d85c05a00f3fc6ced6b96f8d0a1e5137b71ea2bdb", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.72
[INFO] [stderr]     Checking getrandom v0.1.14
[INFO] [stderr]     Checking num_cpus v1.13.0
[INFO] [stderr]     Checking rayon-core v1.7.1
[INFO] [stderr]     Checking rand_core v0.5.1
[INFO] [stderr]     Checking rand_chacha v0.2.2
[INFO] [stderr]     Checking rayon v1.3.1
[INFO] [stderr]     Checking rand v0.7.3
[INFO] [stderr]  Documenting impulse_response v0.6.1 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]    --> src/lib.rs:112:1
[INFO] [stdout]     |
[INFO] [stdout] 112 | #![feature(trait_alias)]
[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 `impulse_response`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name impulse_response 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 rand=/opt/rustwide/target/debug/deps/librand-517cfe4143c151c6.rmeta --extern rayon=/opt/rustwide/target/debug/deps/librayon-17f612364e71cdc8.rmeta --cap-lints=warn --crate-version 0.6.1` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "9ca78934967a6f869747650d85c05a00f3fc6ced6b96f8d0a1e5137b71ea2bdb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9ca78934967a6f869747650d85c05a00f3fc6ced6b96f8d0a1e5137b71ea2bdb", kill_on_drop: false }`
[INFO] [stdout] 9ca78934967a6f869747650d85c05a00f3fc6ced6b96f8d0a1e5137b71ea2bdb
