[INFO] fetching crate prune_derive 0.1.6...
[INFO] documenting prune_derive-0.1.6 against 1.54.0 for beta-1.55-rustdoc-1
[INFO] extracting crate prune_derive 0.1.6 into /workspace/builds/worker-38/source
[INFO] validating manifest of crates.io crate prune_derive 0.1.6 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 prune_derive 0.1.6
[INFO] finished tweaking crates.io crate prune_derive 0.1.6
[INFO] tweaked toml for crates.io crate prune_derive 0.1.6 written to /workspace/builds/worker-38/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] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded prune v0.1.6
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-38/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-38/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] 695c3941775fa3d073de7ed8bd36f89ef36587982105c2046b10fb40edab8945
[INFO] running `Command { std: "docker" "start" "-a" "695c3941775fa3d073de7ed8bd36f89ef36587982105c2046b10fb40edab8945", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "695c3941775fa3d073de7ed8bd36f89ef36587982105c2046b10fb40edab8945", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "695c3941775fa3d073de7ed8bd36f89ef36587982105c2046b10fb40edab8945", kill_on_drop: false }`
[INFO] [stdout] 695c3941775fa3d073de7ed8bd36f89ef36587982105c2046b10fb40edab8945
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-38/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-38/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] e1bf0d8f043f670b3de904f7a64fec3952b815a7648ffda71afbb15f78abeddd
[INFO] running `Command { std: "docker" "start" "-a" "e1bf0d8f043f670b3de904f7a64fec3952b815a7648ffda71afbb15f78abeddd", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking unicode-xid v0.1.0
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]     Checking prune v0.1.6
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/prune-0.1.6/src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(test)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `prune`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "e1bf0d8f043f670b3de904f7a64fec3952b815a7648ffda71afbb15f78abeddd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e1bf0d8f043f670b3de904f7a64fec3952b815a7648ffda71afbb15f78abeddd", kill_on_drop: false }`
[INFO] [stdout] e1bf0d8f043f670b3de904f7a64fec3952b815a7648ffda71afbb15f78abeddd
