[INFO] fetching crate detach 0.0.42...
[INFO] checking detach-0.0.42 against master#da897dfb6daa268a965d2d73620316ba56020a19 for pr-76219
[INFO] extracting crate detach 0.0.42 into /workspace/builds/worker-2/source
[INFO] validating manifest of crates.io crate detach 0.0.42 on toolchain da897dfb6daa268a965d2d73620316ba56020a19
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+da897dfb6daa268a965d2d73620316ba56020a19" "read-manifest" "--manifest-path" "Cargo.toml", 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-2/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+da897dfb6daa268a965d2d73620316ba56020a19" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+da897dfb6daa268a965d2d73620316ba56020a19" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+da897dfb6daa268a965d2d73620316ba56020a19" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 3c2e0b2902a1c94df9177708414c35a5328b594bde4a28970f9499a01ca7d2f7
[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" "3c2e0b2902a1c94df9177708414c35a5328b594bde4a28970f9499a01ca7d2f7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3c2e0b2902a1c94df9177708414c35a5328b594bde4a28970f9499a01ca7d2f7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3c2e0b2902a1c94df9177708414c35a5328b594bde4a28970f9499a01ca7d2f7", kill_on_drop: false }`
[INFO] [stdout] 3c2e0b2902a1c94df9177708414c35a5328b594bde4a28970f9499a01ca7d2f7
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+da897dfb6daa268a965d2d73620316ba56020a19" "check" "--frozen" "--all" "--all-targets" "--message-format=json", 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] 2ceb6f152755b771ed241f6055619d62fe9e8bca8d91a6527b87adcbc1a1e6c4
[INFO] running `Command { std: "docker" "start" "-a" "2ceb6f152755b771ed241f6055619d62fe9e8bca8d91a6527b87adcbc1a1e6c4", 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: 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: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.25s
[INFO] running `Command { std: "docker" "inspect" "2ceb6f152755b771ed241f6055619d62fe9e8bca8d91a6527b87adcbc1a1e6c4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2ceb6f152755b771ed241f6055619d62fe9e8bca8d91a6527b87adcbc1a1e6c4", kill_on_drop: false }`
[INFO] [stdout] 2ceb6f152755b771ed241f6055619d62fe9e8bca8d91a6527b87adcbc1a1e6c4