[INFO] cloning repository https://github.com/llwwns/pairing_heap
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/llwwns/pairing_heap" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fllwwns%2Fpairing_heap", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fllwwns%2Fpairing_heap'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] b8f1c8ff87c95c26a0d04a2ed75c5b818fb34881
[INFO] checking llwwns/pairing_heap against master#1f12b9b0fdbe735968ac002792a720f0ba4faca6 for crater-rollup-uwu
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fllwwns%2Fpairing_heap" "/workspace/builds/worker-1-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/llwwns/pairing_heap on toolchain 1f12b9b0fdbe735968ac002792a720f0ba4faca6
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1f12b9b0fdbe735968ac002792a720f0ba4faca6" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/llwwns/pairing_heap
[INFO] finished tweaking git repo https://github.com/llwwns/pairing_heap
[INFO] tweaked toml for git repo https://github.com/llwwns/pairing_heap written to /workspace/builds/worker-1-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/llwwns/pairing_heap already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1f12b9b0fdbe735968ac002792a720f0ba4faca6" "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-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+1f12b9b0fdbe735968ac002792a720f0ba4faca6" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] c52c95290f3b33239d1570c2cfd6a484e8d90605d6802bb558be746515a32e6f
[INFO] running `Command { std: "docker" "start" "-a" "c52c95290f3b33239d1570c2cfd6a484e8d90605d6802bb558be746515a32e6f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c52c95290f3b33239d1570c2cfd6a484e8d90605d6802bb558be746515a32e6f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c52c95290f3b33239d1570c2cfd6a484e8d90605d6802bb558be746515a32e6f", kill_on_drop: false }`
[INFO] [stdout] c52c95290f3b33239d1570c2cfd6a484e8d90605d6802bb558be746515a32e6f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/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" "RUSTDOCFLAGS=--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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+1f12b9b0fdbe735968ac002792a720f0ba4faca6" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 00f8c51db192dfec9b98a517cefe0cdd3a86872c09d6952d2e7dec26cf55571a
[INFO] running `Command { std: "docker" "start" "-a" "00f8c51db192dfec9b98a517cefe0cdd3a86872c09d6952d2e7dec26cf55571a", kill_on_drop: false }`
[INFO] [stderr]     Checking pairing_heap v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/forward_list.rs:291:7
[INFO] [stdout]     |
[INFO] [stdout] 291 |   let mut x: Vec<_> = a.into_iter().collect();
[INFO] [stdout]     |       ----^
[INFO] [stdout]     |       |
[INFO] [stdout]     |       help: remove this `mut`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.08s
[INFO] running `Command { std: "docker" "inspect" "00f8c51db192dfec9b98a517cefe0cdd3a86872c09d6952d2e7dec26cf55571a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "00f8c51db192dfec9b98a517cefe0cdd3a86872c09d6952d2e7dec26cf55571a", kill_on_drop: false }`
[INFO] [stdout] 00f8c51db192dfec9b98a517cefe0cdd3a86872c09d6952d2e7dec26cf55571a