[INFO] fetching crate detach 0.0.42...
[INFO] checking detach-0.0.42 against try#24cd45d7714ba43afd4b8e62fb677b069b21c4a5 for pr-129543
[INFO] extracting crate detach 0.0.42 into /workspace/builds/worker-5-tc2/source
[INFO] validating manifest of crates.io crate detach 0.0.42 on toolchain 24cd45d7714ba43afd4b8e62fb677b069b21c4a5
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+24cd45d7714ba43afd4b8e62fb677b069b21c4a5" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate detach 0.0.42
[INFO] finished tweaking crates.io crate detach 0.0.42
[INFO] tweaked toml for crates.io crate detach 0.0.42 written to /workspace/builds/worker-5-tc2/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+24cd45d7714ba43afd4b8e62fb677b069b21c4a5" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+24cd45d7714ba43afd4b8e62fb677b069b21c4a5" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc2/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" "+24cd45d7714ba43afd4b8e62fb677b069b21c4a5" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 6d5314224ed1788b924d734e1f41aaa417d515f2a373abc24ce1eb9f5cfea0a7
[INFO] running `Command { std: "docker" "start" "-a" "6d5314224ed1788b924d734e1f41aaa417d515f2a373abc24ce1eb9f5cfea0a7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6d5314224ed1788b924d734e1f41aaa417d515f2a373abc24ce1eb9f5cfea0a7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6d5314224ed1788b924d734e1f41aaa417d515f2a373abc24ce1eb9f5cfea0a7", kill_on_drop: false }`
[INFO] [stdout] 6d5314224ed1788b924d734e1f41aaa417d515f2a373abc24ce1eb9f5cfea0a7
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc2/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" "+24cd45d7714ba43afd4b8e62fb677b069b21c4a5" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 8c10d4d43ae27f794bcba34337de894268ef854c42e4c7ec0275b9b2488b396b
[INFO] running `Command { std: "docker" "start" "-a" "8c10d4d43ae27f794bcba34337de894268ef854c42e4c7ec0275b9b2488b396b", kill_on_drop: false }`
[INFO] [stderr]     Checking detach v0.0.42 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/lib.rs:169:9
[INFO] [stdout]     |
[INFO] [stdout] 169 |         std::mem::replace(&mut self.0, Some(t));
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 169 |         let _ = std::mem::replace(&mut self.0, Some(t));
[INFO] [stdout]     |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/lib.rs:169:9
[INFO] [stdout]     |
[INFO] [stdout] 169 |         std::mem::replace(&mut self.0, Some(t));
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 169 |         let _ = std::mem::replace(&mut self.0, Some(t));
[INFO] [stdout]     |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.21s
[INFO] running `Command { std: "docker" "inspect" "8c10d4d43ae27f794bcba34337de894268ef854c42e4c7ec0275b9b2488b396b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8c10d4d43ae27f794bcba34337de894268ef854c42e4c7ec0275b9b2488b396b", kill_on_drop: false }`
[INFO] [stdout] 8c10d4d43ae27f794bcba34337de894268ef854c42e4c7ec0275b9b2488b396b