[INFO] cloning repository https://github.com/vorner/fade
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/vorner/fade" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fvorner%2Ffade", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fvorner%2Ffade'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 9410927523be717fefc152a4ade78a1baff8163d
[INFO] documenting vorner/fade against 1.54.0 for beta-1.55-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fvorner%2Ffade" "/workspace/builds/worker-2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/vorner/fade 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 git repo https://github.com/vorner/fade
[INFO] finished tweaking git repo https://github.com/vorner/fade
[INFO] tweaked toml for git repo https://github.com/vorner/fade written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] crate git repo https://github.com/vorner/fade 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] 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] 9609831acc5e0c9a3249916e9981c8d88d213b5c6ad05803f94acc06eaf2a2cb
[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" "9609831acc5e0c9a3249916e9981c8d88d213b5c6ad05803f94acc06eaf2a2cb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "9609831acc5e0c9a3249916e9981c8d88d213b5c6ad05803f94acc06eaf2a2cb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9609831acc5e0c9a3249916e9981c8d88d213b5c6ad05803f94acc06eaf2a2cb", kill_on_drop: false }`
[INFO] [stdout] 9609831acc5e0c9a3249916e9981c8d88d213b5c6ad05803f94acc06eaf2a2cb
[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] 26345443eb501dab5f843c332b8cd6ceac2d037d89e2c5f1a69ce80accfeeff2
[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" "26345443eb501dab5f843c332b8cd6ceac2d037d89e2c5f1a69ce80accfeeff2", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.58
[INFO] [stderr]     Checking getrandom v0.2.2
[INFO] [stderr]     Checking num_cpus v1.13.0
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking slipstream v0.1.1
[INFO] [stderr]     Checking clap v2.33.3
[INFO] [stderr]     Checking rayon-core v1.9.0
[INFO] [stderr]     Checking rand_core v0.6.1
[INFO] [stderr]     Checking rand_chacha v0.3.0
[INFO] [stderr]     Checking rayon v1.5.0
[INFO] [stderr]     Checking rand v0.8.2
[INFO] [stderr]    Compiling proc-macro-error v1.0.4
[INFO] [stderr]    Compiling multiversion-macros v0.6.1
[INFO] [stderr]    Compiling structopt-derive v0.4.14
[INFO] [stderr]     Checking multiversion v0.6.1
[INFO] [stderr]     Checking structopt v0.3.21
[INFO] [stderr]  Documenting fade v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/main.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(bench_black_box)]
[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 `fade`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type bin --crate-name fade src/main.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi --document-private-items -L dependency=/opt/rustwide/target/debug/deps --extern multiversion=/opt/rustwide/target/debug/deps/libmultiversion-34fafd4dcd76353a.rmeta --extern rand=/opt/rustwide/target/debug/deps/librand-ad756de33afbeb03.rmeta --extern rayon=/opt/rustwide/target/debug/deps/librayon-02c0846820f58c15.rmeta --extern slipstream=/opt/rustwide/target/debug/deps/libslipstream-078e85c59e0f5538.rmeta --extern structopt=/opt/rustwide/target/debug/deps/libstructopt-647be09cbecdc3f2.rmeta --cap-lints=warn --crate-version 0.1.0` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "26345443eb501dab5f843c332b8cd6ceac2d037d89e2c5f1a69ce80accfeeff2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "26345443eb501dab5f843c332b8cd6ceac2d037d89e2c5f1a69ce80accfeeff2", kill_on_drop: false }`
[INFO] [stdout] 26345443eb501dab5f843c332b8cd6ceac2d037d89e2c5f1a69ce80accfeeff2
