[INFO] fetching crate muto 0.1.0...
[INFO] checking muto-0.1.0 against try#cac44d9528e3bbbdaa1537d187bd489ccc5de18c for pr-91141
[INFO] extracting crate muto 0.1.0 into /workspace/builds/worker-108/source
[INFO] validating manifest of crates.io crate muto 0.1.0 on toolchain cac44d9528e3bbbdaa1537d187bd489ccc5de18c
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+cac44d9528e3bbbdaa1537d187bd489ccc5de18c" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate muto 0.1.0
[INFO] finished tweaking crates.io crate muto 0.1.0
[INFO] tweaked toml for crates.io crate muto 0.1.0 written to /workspace/builds/worker-108/source/Cargo.toml
[INFO] crate crates.io crate muto 0.1.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+cac44d9528e3bbbdaa1537d187bd489ccc5de18c" "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-108/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-108/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@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+cac44d9528e3bbbdaa1537d187bd489ccc5de18c" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 7d729d9a84caccda686f30cad155e7f8e78b086965f22f536a1c90bdd4be5a72
[INFO] running `Command { std: "docker" "start" "-a" "7d729d9a84caccda686f30cad155e7f8e78b086965f22f536a1c90bdd4be5a72", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7d729d9a84caccda686f30cad155e7f8e78b086965f22f536a1c90bdd4be5a72", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7d729d9a84caccda686f30cad155e7f8e78b086965f22f536a1c90bdd4be5a72", kill_on_drop: false }`
[INFO] [stdout] 7d729d9a84caccda686f30cad155e7f8e78b086965f22f536a1c90bdd4be5a72
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-108/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-108/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@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+cac44d9528e3bbbdaa1537d187bd489ccc5de18c" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 5f9593a36141fdc1ec495471abe647d3e3eb424ca6dc9c139533508dc78636b8
[INFO] running `Command { std: "docker" "start" "-a" "5f9593a36141fdc1ec495471abe647d3e3eb424ca6dc9c139533508dc78636b8", kill_on_drop: false }`
[INFO] [stderr]     Checking muto v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::mem::take`
[INFO] [stdout]   --> src/lib.rs:10:5
[INFO] [stdout]    |
[INFO] [stdout] 10 | use std::mem::take;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::mem::take`
[INFO] [stdout]   --> src/lib.rs:10:5
[INFO] [stdout]    |
[INFO] [stdout] 10 | use std::mem::take;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `prev_task`
[INFO] [stdout]    --> src/lib.rs:236:2
[INFO] [stdout]     |
[INFO] [stdout] 236 |     prev_task: Task,
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `next_task`
[INFO] [stdout]    --> src/lib.rs:237:2
[INFO] [stdout]     |
[INFO] [stdout] 237 |     next_task: Task,
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `prev_task`
[INFO] [stdout]    --> src/lib.rs:236:2
[INFO] [stdout]     |
[INFO] [stdout] 236 |     prev_task: Task,
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `next_task`
[INFO] [stdout]    --> src/lib.rs:237:2
[INFO] [stdout]     |
[INFO] [stdout] 237 |     next_task: Task,
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `solutions`
[INFO] [stdout]   --> src/main.rs:38:6
[INFO] [stdout]    |
[INFO] [stdout] 38 |     let solutions = muto.solve();
[INFO] [stdout]    |         ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_solutions`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `solutions`
[INFO] [stdout]   --> src/main.rs:38:6
[INFO] [stdout]    |
[INFO] [stdout] 38 |     let solutions = muto.solve();
[INFO] [stdout]    |         ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_solutions`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.47s
[INFO] running `Command { std: "docker" "inspect" "5f9593a36141fdc1ec495471abe647d3e3eb424ca6dc9c139533508dc78636b8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5f9593a36141fdc1ec495471abe647d3e3eb424ca6dc9c139533508dc78636b8", kill_on_drop: false }`
[INFO] [stdout] 5f9593a36141fdc1ec495471abe647d3e3eb424ca6dc9c139533508dc78636b8