[INFO] fetching crate kant 0.0.3...
[INFO] checking kant-0.0.3 against try#3d9fdbff4f377de96b3a51174e7a64086bee9a5c for pr-81477
[INFO] extracting crate kant 0.0.3 into /workspace/builds/worker-9/source
[INFO] validating manifest of crates.io crate kant 0.0.3 on toolchain 3d9fdbff4f377de96b3a51174e7a64086bee9a5c
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+3d9fdbff4f377de96b3a51174e7a64086bee9a5c" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate kant 0.0.3
[INFO] finished tweaking crates.io crate kant 0.0.3
[INFO] tweaked toml for crates.io crate kant 0.0.3 written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+3d9fdbff4f377de96b3a51174e7a64086bee9a5c" "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" "+3d9fdbff4f377de96b3a51174e7a64086bee9a5c" "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-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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:ea7d7bff36b2ba8ce4de8bba1d2dea90376bc481f1a945a913994a8c492e40c1" "/opt/rustwide/cargo-home/bin/cargo" "+3d9fdbff4f377de96b3a51174e7a64086bee9a5c" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 4d06c10392bb1f849eb4719c673c1060a092ea5e6a11cb022d10b4e4af8f298b
[INFO] running `Command { std: "docker" "start" "-a" "4d06c10392bb1f849eb4719c673c1060a092ea5e6a11cb022d10b4e4af8f298b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "4d06c10392bb1f849eb4719c673c1060a092ea5e6a11cb022d10b4e4af8f298b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4d06c10392bb1f849eb4719c673c1060a092ea5e6a11cb022d10b4e4af8f298b", kill_on_drop: false }`
[INFO] [stdout] 4d06c10392bb1f849eb4719c673c1060a092ea5e6a11cb022d10b4e4af8f298b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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=forbid" "-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:ea7d7bff36b2ba8ce4de8bba1d2dea90376bc481f1a945a913994a8c492e40c1" "/opt/rustwide/cargo-home/bin/cargo" "+3d9fdbff4f377de96b3a51174e7a64086bee9a5c" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 9f8104c58c8c9eabfba0bf4d22b170d21e407c827f0a672ee15f6a1fec371dc7
[INFO] running `Command { std: "docker" "start" "-a" "9f8104c58c8c9eabfba0bf4d22b170d21e407c827f0a672ee15f6a1fec371dc7", kill_on_drop: false }`
[INFO] [stderr]     Checking kant v0.0.3 (/opt/rustwide/workdir)
[INFO] [stdout] error: unnecessary parentheses around block return value
[INFO] [stdout]    --> src/lib.rs:166:5
[INFO] [stdout]     |
[INFO] [stdout] 166 |     (unboosted.exp() - 1.)
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stdout]     |
[INFO] [stdout] note: the lint level is defined here
[INFO] [stdout]    --> src/lib.rs:26:24
[INFO] [stdout]     |
[INFO] [stdout] 26  | #![cfg_attr(test, deny(warnings))]
[INFO] [stdout]     |                        ^^^^^^^^
[INFO] [stdout]     = note: `#[deny(unused_parens)]` implied by `#[deny(warnings)]`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]    --> src/lib.rs:166:5
[INFO] [stdout]     |
[INFO] [stdout] 166 |     (unboosted.exp() - 1.)
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `kant`
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[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" "9f8104c58c8c9eabfba0bf4d22b170d21e407c827f0a672ee15f6a1fec371dc7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9f8104c58c8c9eabfba0bf4d22b170d21e407c827f0a672ee15f6a1fec371dc7", kill_on_drop: false }`
[INFO] [stdout] 9f8104c58c8c9eabfba0bf4d22b170d21e407c827f0a672ee15f6a1fec371dc7