[INFO] crate disjoint-sets 0.4.2 is already in cache
[INFO] checking disjoint-sets-0.4.2 against try#0ab79c4b48ad19260fa46623f452c1b403a360e8 for pr-74315
[INFO] extracting crate disjoint-sets 0.4.2 into /workspace/builds/worker-14/source
[INFO] validating manifest of crates.io crate disjoint-sets 0.4.2 on toolchain 0ab79c4b48ad19260fa46623f452c1b403a360e8
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+0ab79c4b48ad19260fa46623f452c1b403a360e8" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate disjoint-sets 0.4.2
[INFO] finished tweaking crates.io crate disjoint-sets 0.4.2
[INFO] tweaked toml for crates.io crate disjoint-sets 0.4.2 written to /workspace/builds/worker-14/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+0ab79c4b48ad19260fa46623f452c1b403a360e8" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+0ab79c4b48ad19260fa46623f452c1b403a360e8" "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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:d9fbb4e2287ab3795bdefaf705efb7541a8875c13bce71e067d6b01dc5ed759b" "/opt/rustwide/cargo-home/bin/cargo" "+0ab79c4b48ad19260fa46623f452c1b403a360e8" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] cd11c3057412b03fc448ccb99c6609700e5966b2916998c65d6cc6312188bc23
[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" "cd11c3057412b03fc448ccb99c6609700e5966b2916998c65d6cc6312188bc23", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "cd11c3057412b03fc448ccb99c6609700e5966b2916998c65d6cc6312188bc23", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cd11c3057412b03fc448ccb99c6609700e5966b2916998c65d6cc6312188bc23", kill_on_drop: false }`
[INFO] [stdout] cd11c3057412b03fc448ccb99c6609700e5966b2916998c65d6cc6312188bc23
[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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:d9fbb4e2287ab3795bdefaf705efb7541a8875c13bce71e067d6b01dc5ed759b" "/opt/rustwide/cargo-home/bin/cargo" "+0ab79c4b48ad19260fa46623f452c1b403a360e8" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a043def467327da2937f1c75debfb324df0b21577340aa67c4a95ca5cb308b87
[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" "a043def467327da2937f1c75debfb324df0b21577340aa67c4a95ca5cb308b87", kill_on_drop: false }`
[INFO] [stderr]     Checking disjoint-sets v0.4.2 (/opt/rustwide/workdir)
[INFO] [stderr]     Checking serde_json v1.0.56
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/tree.rs:465:17
[INFO] [stdout]     |
[INFO] [stdout] 465 | /                 mem::replace(&mut *guard_parent, Root {
[INFO] [stdout] 466 | |                     data: new_data,
[INFO] [stdout] 467 | |                     rank: rank,
[INFO] [stdout] 468 | |                 });
[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: use of deprecated item 'try': use the `?` operator instead
[INFO] [stdout]    --> src/tree.rs:668:17
[INFO] [stdout]     |
[INFO] [stdout] 668 |                 try!(self.unify(v1, v2));
[INFO] [stdout]     |                 ^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(deprecated)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/tree.rs:465:17
[INFO] [stdout]     |
[INFO] [stdout] 465 | /                 mem::replace(&mut *guard_parent, Root {
[INFO] [stdout] 466 | |                     data: new_data,
[INFO] [stdout] 467 | |                     rank: rank,
[INFO] [stdout] 468 | |                 });
[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: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 2.18s
[INFO] running `Command { std: "docker" "inspect" "a043def467327da2937f1c75debfb324df0b21577340aa67c4a95ca5cb308b87", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a043def467327da2937f1c75debfb324df0b21577340aa67c4a95ca5cb308b87", kill_on_drop: false }`
[INFO] [stdout] a043def467327da2937f1c75debfb324df0b21577340aa67c4a95ca5cb308b87