[INFO] fetching crate pom 3.2.0...
[INFO] checking pom-3.2.0 against try#45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4 for pr-83744
[INFO] extracting crate pom 3.2.0 into /workspace/builds/worker-0/source
[INFO] validating manifest of crates.io crate pom 3.2.0 on toolchain 45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate pom 3.2.0
[INFO] finished tweaking crates.io crate pom 3.2.0
[INFO] tweaked toml for crates.io crate pom 3.2.0 written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] crate crates.io crate pom 3.2.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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" "rustops/crates-build-env@sha256:c46a2d1a26fb48b37929c74ca49dd9409f2375a0a3bdb8fe07617f3ffccaa889" "/opt/rustwide/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 3c6f2b245ea56bfd712edb99d913bd538e0428cf07598918640822d62fc6741f
[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" "3c6f2b245ea56bfd712edb99d913bd538e0428cf07598918640822d62fc6741f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3c6f2b245ea56bfd712edb99d913bd538e0428cf07598918640822d62fc6741f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3c6f2b245ea56bfd712edb99d913bd538e0428cf07598918640822d62fc6741f", kill_on_drop: false }`
[INFO] [stdout] 3c6f2b245ea56bfd712edb99d913bd538e0428cf07598918640822d62fc6741f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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" "rustops/crates-build-env@sha256:c46a2d1a26fb48b37929c74ca49dd9409f2375a0a3bdb8fe07617f3ffccaa889" "/opt/rustwide/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] fc0f336e0865ff3a1a43fd7b3413b178b218f4563bff7c8e3a844d6c7a15e5d4
[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" "fc0f336e0865ff3a1a43fd7b3413b178b218f4563bff7c8e3a844d6c7a15e5d4", kill_on_drop: false }`
[INFO] [stderr]     Checking pom v3.2.0 (/opt/rustwide/workdir)
[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] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> examples/json_file.rs:75:2
[INFO] [stdout]    |
[INFO] [stdout] 75 |     file.read_to_end(&mut input);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.80s
[INFO] running `Command { std: "docker" "inspect" "fc0f336e0865ff3a1a43fd7b3413b178b218f4563bff7c8e3a844d6c7a15e5d4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fc0f336e0865ff3a1a43fd7b3413b178b218f4563bff7c8e3a844d6c7a15e5d4", kill_on_drop: false }`
[INFO] [stdout] fc0f336e0865ff3a1a43fd7b3413b178b218f4563bff7c8e3a844d6c7a15e5d4