[INFO] fetching crate pom-preview 3.0.4-alpha-1...
[INFO] checking pom-preview-3.0.4-alpha-1 against 1.55.0 for beta-1.56-3
[INFO] extracting crate pom-preview 3.0.4-alpha-1 into /workspace/builds/worker-57/source
[INFO] validating manifest of crates.io crate pom-preview 3.0.4-alpha-1 on toolchain 1.55.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate pom-preview 3.0.4-alpha-1
[INFO] finished tweaking crates.io crate pom-preview 3.0.4-alpha-1
[INFO] tweaked toml for crates.io crate pom-preview 3.0.4-alpha-1 written to /workspace/builds/worker-57/source/Cargo.toml
[INFO] crate crates.io crate pom-preview 3.0.4-alpha-1 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "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-57/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-57/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] dfbcd335861edb90b67fb11240eb42b2b5c22c3188713463cd83c6458778dd81
[INFO] running `Command { std: "docker" "start" "-a" "dfbcd335861edb90b67fb11240eb42b2b5c22c3188713463cd83c6458778dd81", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "dfbcd335861edb90b67fb11240eb42b2b5c22c3188713463cd83c6458778dd81", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "dfbcd335861edb90b67fb11240eb42b2b5c22c3188713463cd83c6458778dd81", kill_on_drop: false }`
[INFO] [stdout] dfbcd335861edb90b67fb11240eb42b2b5c22c3188713463cd83c6458778dd81
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-57/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-57/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" "RUSTFLAGS=--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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 666afb126aed03d650c77fe2887f39f20d862480246290e9cfd7c7a239e13477
[INFO] running `Command { std: "docker" "start" "-a" "666afb126aed03d650c77fe2887f39f20d862480246290e9cfd7c7a239e13477", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking pom-preview v3.0.4-alpha-1 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> benches/json.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(test)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> benches/json_char.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] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]   --> examples/whitespace.rs:77:2
[INFO] [stdout]    |
[INFO] [stdout] 77 | /     (
[INFO] [stdout] 78 | |         whitespace() *
[INFO] [stdout] 79 | |         list(
[INFO] [stdout] 80 | |             call(container),
[INFO] [stdout] 81 | |             whitespace()
[INFO] [stdout] 82 | |         )
[INFO] [stdout] 83 | |     )
[INFO] [stdout]    | |_____^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] help: remove these parentheses
[INFO] [stdout]    |
[INFO] [stdout] 77 |     whitespace() *
[INFO] [stdout] 78 |         list(
[INFO] [stdout] 79 |             call(container),
[INFO] [stdout] 80 |             whitespace()
[INFO] [stdout] 81 |         )
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `pom-preview` due to 2 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[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] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "666afb126aed03d650c77fe2887f39f20d862480246290e9cfd7c7a239e13477", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "666afb126aed03d650c77fe2887f39f20d862480246290e9cfd7c7a239e13477", kill_on_drop: false }`
[INFO] [stdout] 666afb126aed03d650c77fe2887f39f20d862480246290e9cfd7c7a239e13477
