[INFO] fetching crate marching-buffer 0.1.0...
[INFO] checking marching-buffer-0.1.0 against try#cac44d9528e3bbbdaa1537d187bd489ccc5de18c for pr-91141
[INFO] extracting crate marching-buffer 0.1.0 into /workspace/builds/worker-118/source
[INFO] validating manifest of crates.io crate marching-buffer 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 marching-buffer 0.1.0
[INFO] finished tweaking crates.io crate marching-buffer 0.1.0
[INFO] tweaked toml for crates.io crate marching-buffer 0.1.0 written to /workspace/builds/worker-118/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+cac44d9528e3bbbdaa1537d187bd489ccc5de18c" "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" "+cac44d9528e3bbbdaa1537d187bd489ccc5de18c" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-118/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-118/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] 665ed7796d403c7eca562fc5105613c378f38dc554368747b8c955d1a4234ee2
[INFO] running `Command { std: "docker" "start" "-a" "665ed7796d403c7eca562fc5105613c378f38dc554368747b8c955d1a4234ee2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "665ed7796d403c7eca562fc5105613c378f38dc554368747b8c955d1a4234ee2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "665ed7796d403c7eca562fc5105613c378f38dc554368747b8c955d1a4234ee2", kill_on_drop: false }`
[INFO] [stdout] 665ed7796d403c7eca562fc5105613c378f38dc554368747b8c955d1a4234ee2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-118/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-118/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] a8b3d703b5af4a7861a9ccdbd814ced7f7ba7e1ac35beb5f9bfcb51b78aec672
[INFO] running `Command { std: "docker" "start" "-a" "a8b3d703b5af4a7861a9ccdbd814ced7f7ba7e1ac35beb5f9bfcb51b78aec672", kill_on_drop: false }`
[INFO] [stderr]     Checking marching-buffer v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]    --> src/lib.rs:255:13
[INFO] [stdout]     |
[INFO] [stdout] 255 | ...   &mut copy_buffer[..copied_this_round].copy_from_slice(&reader.access().as_slice()[bytes_copied .. (bytes_copied + copied_this_round)...
[INFO] [stdout]     |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 255 |             let _ = &mut copy_buffer[..copied_this_round].copy_from_slice(&reader.access().as_slice()[bytes_copied .. (bytes_copied + copied_this_round)]);
[INFO] [stdout]     |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]    --> src/lib.rs:255:13
[INFO] [stdout]     |
[INFO] [stdout] 255 | ...   &mut copy_buffer[..copied_this_round].copy_from_slice(&reader.access().as_slice()[bytes_copied .. (bytes_copied + copied_this_round)...
[INFO] [stdout]     |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 255 |             let _ = &mut copy_buffer[..copied_this_round].copy_from_slice(&reader.access().as_slice()[bytes_copied .. (bytes_copied + copied_this_round)]);
[INFO] [stdout]     |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.21s
[INFO] running `Command { std: "docker" "inspect" "a8b3d703b5af4a7861a9ccdbd814ced7f7ba7e1ac35beb5f9bfcb51b78aec672", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a8b3d703b5af4a7861a9ccdbd814ced7f7ba7e1ac35beb5f9bfcb51b78aec672", kill_on_drop: false }`
[INFO] [stdout] a8b3d703b5af4a7861a9ccdbd814ced7f7ba7e1ac35beb5f9bfcb51b78aec672