[INFO] fetching crate detach 0.0.42...
[INFO] checking detach-0.0.42 against master#a5f164faad4a2fed606b8160fd7ecd2d5cbba381 for pr-84920
[INFO] extracting crate detach 0.0.42 into /workspace/builds/worker-14/source
[INFO] validating manifest of crates.io crate detach 0.0.42 on toolchain a5f164faad4a2fed606b8160fd7ecd2d5cbba381
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+a5f164faad4a2fed606b8160fd7ecd2d5cbba381" "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-14/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+a5f164faad4a2fed606b8160fd7ecd2d5cbba381" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+a5f164faad4a2fed606b8160fd7ecd2d5cbba381" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/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@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+a5f164faad4a2fed606b8160fd7ecd2d5cbba381" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 2a8520a09412172dd18998e9a7ba7ec14bcd10ccd45eaf01eea8c0c0851f0b38
[INFO] running `Command { std: "docker" "start" "-a" "2a8520a09412172dd18998e9a7ba7ec14bcd10ccd45eaf01eea8c0c0851f0b38", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2a8520a09412172dd18998e9a7ba7ec14bcd10ccd45eaf01eea8c0c0851f0b38", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2a8520a09412172dd18998e9a7ba7ec14bcd10ccd45eaf01eea8c0c0851f0b38", kill_on_drop: false }`
[INFO] [stdout] 2a8520a09412172dd18998e9a7ba7ec14bcd10ccd45eaf01eea8c0c0851f0b38
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/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@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+a5f164faad4a2fed606b8160fd7ecd2d5cbba381" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] af18d63b3bf8d9601ee4f461031e36975924cf05f4c009244fb2aab290a7e8e5
[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" "af18d63b3bf8d9601ee4f461031e36975924cf05f4c009244fb2aab290a7e8e5", 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: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[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: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.59s
[INFO] running `Command { std: "docker" "inspect" "af18d63b3bf8d9601ee4f461031e36975924cf05f4c009244fb2aab290a7e8e5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "af18d63b3bf8d9601ee4f461031e36975924cf05f4c009244fb2aab290a7e8e5", kill_on_drop: false }`
[INFO] [stdout] af18d63b3bf8d9601ee4f461031e36975924cf05f4c009244fb2aab290a7e8e5