[INFO] fetching crate skiplist 0.3.0...
[INFO] testing skiplist-0.3.0 against 1.47.0 for beta-1.48-1
[INFO] extracting crate skiplist 0.3.0 into /workspace/builds/worker-13/source
[INFO] validating manifest of crates.io crate skiplist 0.3.0 on toolchain 1.47.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate skiplist 0.3.0
[INFO] finished tweaking crates.io crate skiplist 0.3.0
[INFO] tweaked toml for crates.io crate skiplist 0.3.0 written to /workspace/builds/worker-13/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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" "+1.47.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] ed61718aba2fd5bf5b9897573cf96480a688248db8b7aeb9e83772bd23b2b592
[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" "ed61718aba2fd5bf5b9897573cf96480a688248db8b7aeb9e83772bd23b2b592", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ed61718aba2fd5bf5b9897573cf96480a688248db8b7aeb9e83772bd23b2b592", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ed61718aba2fd5bf5b9897573cf96480a688248db8b7aeb9e83772bd23b2b592", kill_on_drop: false }`
[INFO] [stdout] ed61718aba2fd5bf5b9897573cf96480a688248db8b7aeb9e83772bd23b2b592
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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=warn" "-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" "+1.47.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 6cb3242f44451f75496675bc12ed0d8d942507eba31d6f62d941d095574a169c
[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" "6cb3242f44451f75496675bc12ed0d8d942507eba31d6f62d941d095574a169c", kill_on_drop: false }`
[INFO] [stderr]    Compiling skiplist v0.3.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/ordered_skiplist.rs:249:17
[INFO] [stdout]     |
[INFO] [stdout] 249 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[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/ordered_skiplist.rs:254:9
[INFO] [stdout]     |
[INFO] [stdout] 254 |         mem::replace(&mut self.head, new_head);
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/ordered_skiplist.rs:882:21
[INFO] [stdout]     |
[INFO] [stdout] 882 |                     mem::replace(&mut (*prev).next, mem::replace(&mut (*node).next, None));
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/ordered_skiplist.rs:961:21
[INFO] [stdout]     |
[INFO] [stdout] 961 |                     mem::replace(&mut (*prev).next, mem::replace(&mut (*node).next, None));
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]     --> src/ordered_skiplist.rs:1397:17
[INFO] [stdout]      |
[INFO] [stdout] 1397 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]   --> src/skiplist.rs:95:17
[INFO] [stdout]    |
[INFO] [stdout] 95 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/skiplist.rs:100:9
[INFO] [stdout]     |
[INFO] [stdout] 100 |         mem::replace(&mut self.head, new_head);
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/skiplist.rs:583:21
[INFO] [stdout]     |
[INFO] [stdout] 583 |                     mem::replace(&mut (*prev).next, mem::replace(&mut (*node).next, None));
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/skiplist.rs:886:21
[INFO] [stdout]     |
[INFO] [stdout] 886 |                     mem::replace(&mut (*prev).next, mem::replace(&mut (*node).next, None));
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]     --> src/skiplist.rs:1120:17
[INFO] [stdout]      |
[INFO] [stdout] 1120 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/skipmap.rs:309:17
[INFO] [stdout]     |
[INFO] [stdout] 309 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/skipmap.rs:314:9
[INFO] [stdout]     |
[INFO] [stdout] 314 |         mem::replace(&mut self.head, new_head);
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]     --> src/skipmap.rs:1293:17
[INFO] [stdout]      |
[INFO] [stdout] 1293 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: 13 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.48s
[INFO] running `Command { std: "docker" "inspect" "6cb3242f44451f75496675bc12ed0d8d942507eba31d6f62d941d095574a169c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6cb3242f44451f75496675bc12ed0d8d942507eba31d6f62d941d095574a169c", kill_on_drop: false }`
[INFO] [stdout] 6cb3242f44451f75496675bc12ed0d8d942507eba31d6f62d941d095574a169c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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=warn" "-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" "+1.47.0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 2f3552aea1344b4cb3305e5de35cdbe3d69257b162e0675156973daf99e98124
[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" "2f3552aea1344b4cb3305e5de35cdbe3d69257b162e0675156973daf99e98124", kill_on_drop: false }`
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/ordered_skiplist.rs:249:17
[INFO] [stdout]     |
[INFO] [stdout] 249 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[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/ordered_skiplist.rs:254:9
[INFO] [stdout]     |
[INFO] [stdout] 254 |         mem::replace(&mut self.head, new_head);
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/ordered_skiplist.rs:882:21
[INFO] [stdout]     |
[INFO] [stdout] 882 |                     mem::replace(&mut (*prev).next, mem::replace(&mut (*node).next, None));
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/ordered_skiplist.rs:961:21
[INFO] [stdout]     |
[INFO] [stdout] 961 |                     mem::replace(&mut (*prev).next, mem::replace(&mut (*node).next, None));
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]     --> src/ordered_skiplist.rs:1397:17
[INFO] [stdout]      |
[INFO] [stdout] 1397 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]   --> src/skiplist.rs:95:17
[INFO] [stdout]    |
[INFO] [stdout] 95 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/skiplist.rs:100:9
[INFO] [stdout]     |
[INFO] [stdout] 100 |         mem::replace(&mut self.head, new_head);
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/skiplist.rs:583:21
[INFO] [stdout]     |
[INFO] [stdout] 583 |                     mem::replace(&mut (*prev).next, mem::replace(&mut (*node).next, None));
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/skiplist.rs:886:21
[INFO] [stdout]     |
[INFO] [stdout] 886 |                     mem::replace(&mut (*prev).next, mem::replace(&mut (*node).next, None));
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]     --> src/skiplist.rs:1120:17
[INFO] [stdout]      |
[INFO] [stdout] 1120 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/skipmap.rs:309:17
[INFO] [stdout]     |
[INFO] [stdout] 309 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/skipmap.rs:314:9
[INFO] [stdout]     |
[INFO] [stdout] 314 |         mem::replace(&mut self.head, new_head);
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]     --> src/skipmap.rs:1293:17
[INFO] [stdout]      |
[INFO] [stdout] 1293 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: 13 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling skiplist v0.3.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/ordered_skiplist.rs:249:17
[INFO] [stdout]     |
[INFO] [stdout] 249 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[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/ordered_skiplist.rs:254:9
[INFO] [stdout]     |
[INFO] [stdout] 254 |         mem::replace(&mut self.head, new_head);
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/ordered_skiplist.rs:882:21
[INFO] [stdout]     |
[INFO] [stdout] 882 |                     mem::replace(&mut (*prev).next, mem::replace(&mut (*node).next, None));
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/ordered_skiplist.rs:961:21
[INFO] [stdout]     |
[INFO] [stdout] 961 |                     mem::replace(&mut (*prev).next, mem::replace(&mut (*node).next, None));
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]     --> src/ordered_skiplist.rs:1397:17
[INFO] [stdout]      |
[INFO] [stdout] 1397 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]   --> src/skiplist.rs:95:17
[INFO] [stdout]    |
[INFO] [stdout] 95 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/skiplist.rs:100:9
[INFO] [stdout]     |
[INFO] [stdout] 100 |         mem::replace(&mut self.head, new_head);
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/skiplist.rs:583:21
[INFO] [stdout]     |
[INFO] [stdout] 583 |                     mem::replace(&mut (*prev).next, mem::replace(&mut (*node).next, None));
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/skiplist.rs:886:21
[INFO] [stdout]     |
[INFO] [stdout] 886 |                     mem::replace(&mut (*prev).next, mem::replace(&mut (*node).next, None));
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]     --> src/skiplist.rs:1120:17
[INFO] [stdout]      |
[INFO] [stdout] 1120 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/skipmap.rs:309:17
[INFO] [stdout]     |
[INFO] [stdout] 309 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/skipmap.rs:314:9
[INFO] [stdout]     |
[INFO] [stdout] 314 |         mem::replace(&mut self.head, new_head);
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]     --> src/skipmap.rs:1293:17
[INFO] [stdout]      |
[INFO] [stdout] 1293 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: 13 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 3.60s
[INFO] running `Command { std: "docker" "inspect" "2f3552aea1344b4cb3305e5de35cdbe3d69257b162e0675156973daf99e98124", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2f3552aea1344b4cb3305e5de35cdbe3d69257b162e0675156973daf99e98124", kill_on_drop: false }`
[INFO] [stdout] 2f3552aea1344b4cb3305e5de35cdbe3d69257b162e0675156973daf99e98124
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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=warn" "-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" "+1.47.0" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] faafbcebe8b8937d9ad5d91149ce80a335a95b13b7bfe7e8b684e289488af5a9
[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" "faafbcebe8b8937d9ad5d91149ce80a335a95b13b7bfe7e8b684e289488af5a9", kill_on_drop: false }`
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]    --> src/ordered_skiplist.rs:249:17
[INFO] [stderr]     |
[INFO] [stderr] 249 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[INFO] [stderr]     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]    --> src/ordered_skiplist.rs:254:9
[INFO] [stderr]     |
[INFO] [stderr] 254 |         mem::replace(&mut self.head, new_head);
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]    --> src/ordered_skiplist.rs:882:21
[INFO] [stderr]     |
[INFO] [stderr] 882 |                     mem::replace(&mut (*prev).next, mem::replace(&mut (*node).next, None));
[INFO] [stderr]     |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]    --> src/ordered_skiplist.rs:961:21
[INFO] [stderr]     |
[INFO] [stderr] 961 |                     mem::replace(&mut (*prev).next, mem::replace(&mut (*node).next, None));
[INFO] [stderr]     |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]     --> src/ordered_skiplist.rs:1397:17
[INFO] [stderr]      |
[INFO] [stderr] 1397 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[INFO] [stderr]      |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]      |
[INFO] [stderr]      = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]   --> src/skiplist.rs:95:17
[INFO] [stderr]    |
[INFO] [stderr] 95 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[INFO] [stderr]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]    --> src/skiplist.rs:100:9
[INFO] [stderr]     |
[INFO] [stderr] 100 |         mem::replace(&mut self.head, new_head);
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]    --> src/skiplist.rs:583:21
[INFO] [stderr]     |
[INFO] [stderr] 583 |                     mem::replace(&mut (*prev).next, mem::replace(&mut (*node).next, None));
[INFO] [stderr]     |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]    --> src/skiplist.rs:886:21
[INFO] [stderr]     |
[INFO] [stderr] 886 |                     mem::replace(&mut (*prev).next, mem::replace(&mut (*node).next, None));
[INFO] [stderr]     |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]     --> src/skiplist.rs:1120:17
[INFO] [stderr]      |
[INFO] [stderr] 1120 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[INFO] [stderr]      |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]      |
[INFO] [stderr]      = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]    --> src/skipmap.rs:309:17
[INFO] [stderr]     |
[INFO] [stderr] 309 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[INFO] [stderr]     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]    --> src/skipmap.rs:314:9
[INFO] [stderr]     |
[INFO] [stderr] 314 |         mem::replace(&mut self.head, new_head);
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]     --> src/skipmap.rs:1293:17
[INFO] [stderr]      |
[INFO] [stderr] 1293 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[INFO] [stderr]      |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]      |
[INFO] [stderr]      = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: 13 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]    --> src/ordered_skiplist.rs:249:17
[INFO] [stderr]     |
[INFO] [stderr] 249 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[INFO] [stderr]     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]    --> src/ordered_skiplist.rs:254:9
[INFO] [stderr]     |
[INFO] [stderr] 254 |         mem::replace(&mut self.head, new_head);
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]    --> src/ordered_skiplist.rs:882:21
[INFO] [stderr]     |
[INFO] [stderr] 882 |                     mem::replace(&mut (*prev).next, mem::replace(&mut (*node).next, None));
[INFO] [stderr]     |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]    --> src/ordered_skiplist.rs:961:21
[INFO] [stderr]     |
[INFO] [stderr] 961 |                     mem::replace(&mut (*prev).next, mem::replace(&mut (*node).next, None));
[INFO] [stderr]     |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]     --> src/ordered_skiplist.rs:1397:17
[INFO] [stderr]      |
[INFO] [stderr] 1397 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[INFO] [stderr]      |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]      |
[INFO] [stderr]      = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]   --> src/skiplist.rs:95:17
[INFO] [stderr]    |
[INFO] [stderr] 95 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[INFO] [stderr]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]    --> src/skiplist.rs:100:9
[INFO] [stderr]     |
[INFO] [stderr] 100 |         mem::replace(&mut self.head, new_head);
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]    --> src/skiplist.rs:583:21
[INFO] [stderr]     |
[INFO] [stderr] 583 |                     mem::replace(&mut (*prev).next, mem::replace(&mut (*node).next, None));
[INFO] [stderr]     |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]    --> src/skiplist.rs:886:21
[INFO] [stderr]     |
[INFO] [stderr] 886 |                     mem::replace(&mut (*prev).next, mem::replace(&mut (*node).next, None));
[INFO] [stderr]     |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]     --> src/skiplist.rs:1120:17
[INFO] [stderr]      |
[INFO] [stderr] 1120 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[INFO] [stderr]      |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]      |
[INFO] [stderr]      = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]    --> src/skipmap.rs:309:17
[INFO] [stderr]     |
[INFO] [stderr] 309 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[INFO] [stderr]     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]    --> src/skipmap.rs:314:9
[INFO] [stderr]     |
[INFO] [stderr] 314 |         mem::replace(&mut self.head, new_head);
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]     --> src/skipmap.rs:1293:17
[INFO] [stderr]      |
[INFO] [stderr] 1293 |                 mem::replace(&mut (*node).next, mem::replace(&mut next.next, None));
[INFO] [stderr]      |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]      |
[INFO] [stderr]      = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: 13 warnings emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.14s
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/skiplist-554ac1ea535c872a
[INFO] [stdout] 
[INFO] [stdout] running 58 tests
[INFO] [stdout] test ordered_skiplist::tests::contains ... ok
[INFO] [stdout] test ordered_skiplist::tests::debug_display ... ok
[INFO] [stdout] test level_generator::tests::new ... ok
[INFO] [stdout] test ordered_skiplist::tests::clear ... ok
[INFO] [stdout] test ordered_skiplist::tests::basic_small ... ok
[INFO] [stdout] test ordered_skiplist::tests::equality ... ok
[INFO] [stdout] test ordered_skiplist::tests::range_small ... ok
[INFO] [stdout] test ordered_skiplist::tests::sort_by ... ok
[INFO] [stdout] test ordered_skiplist::tests::remove ... ok
[INFO] [stdout] test ordered_skiplist::tests::with_comp ... ok
[INFO] [stdout] test ordered_skiplist::tests::range_1000 ... ok
[INFO] [stdout] test skiplist::tests::basic_small ... ok
[INFO] [stdout] test skiplist::tests::clear ... ok
[INFO] [stdout] test skiplist::tests::contains ... ok
[INFO] [stdout] test skiplist::tests::debug_display ... ok
[INFO] [stdout] test ordered_skiplist::tests::remove_index ... ok
[INFO] [stdout] test skiplist::tests::equality ... ok
[INFO] [stdout] test ordered_skiplist::tests::index_pop ... ok
[INFO] [stdout] test skiplist::tests::inplace_mut ... ok
[INFO] [stdout] test skiplist::tests::index_pop ... ok
[INFO] [stdout] test ordered_skiplist::tests::pop ... ok
[INFO] [stdout] test level_generator::tests::invalid_total ... ok
[INFO] [stdout] test level_generator::tests::invalid_p_1 ... ok
[INFO] [stdout] test level_generator::tests::invalid_p_0 ... ok
[INFO] [stdout] test skiplist::tests::range_1000 ... ok
[INFO] [stdout] test skiplist::tests::range_small ... ok
[INFO] [stdout] test ordered_skiplist::tests::range ... ok
[INFO] [stdout] test ordered_skiplist::tests::sort_by_panic ... ok
[INFO] [stdout] test skipmap::tests::basic_small ... ok
[INFO] [stdout] test skiplist::tests::range_mut_1000 ... ok
[INFO] [stdout] test skipmap::tests::clear ... ok
[INFO] [stdout] test skipmap::tests::contains ... ok
[INFO] [stdout] test skipmap::tests::debug_display ... ok
[INFO] [stdout] test skipmap::tests::equality ... ok
[INFO] [stdout] test skipmap::tests::insert_existing ... ok
[INFO] [stdout] test ordered_skiplist::tests::iter_mixed ... ok
[INFO] [stdout] test ordered_skiplist::tests::iter_rev ... ok
[INFO] [stdout] test ordered_skiplist::tests::basic_large ... ok
[INFO] [stdout] test skipmap::tests::iter_key_val ... ok
[INFO] [stdout] test skipmap::tests::iter_mixed ... ok
[INFO] [stdout] test ordered_skiplist::tests::iter ... ok
[INFO] [stdout] test skipmap::tests::iter_rev ... ok
[INFO] [stdout] test ordered_skiplist::tests::retain ... ok
[INFO] [stdout] test skipmap::tests::range_1000 ... ok
[INFO] [stdout] test skipmap::tests::index_pop ... ok
[INFO] [stdout] test skipmap::tests::range_small ... ok
[INFO] [stdout] test skiplist::tests::iter ... ok
[INFO] [stdout] test skipmap::tests::remove_index ... ok
[INFO] [stdout] test skiplist::tests::iter_mixed ... ok
[INFO] [stdout] test skiplist::tests::iter_rev ... ok
[INFO] [stdout] test skiplist::tests::retain ... ok
[INFO] [stdout] test skipmap::tests::iter ... ok
[INFO] [stdout] test skipmap::tests::basic_large ... ok
[INFO] [stdout] test skipmap::tests::range ... ok
[INFO] [stdout] test skiplist::tests::range ... ok
[INFO] [stdout] test skiplist::tests::basic_large ... ok
[INFO] [stdout] test ordered_skiplist::tests::dedup ... ok
[INFO] [stdout] test skiplist::tests::dedup ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 58 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] [stderr]    Doc-tests skiplist
[INFO] [stdout] 
[INFO] [stdout] running 69 tests
[INFO] [stdout] test src/ordered_skiplist.rs - ordered_skiplist::OrderedSkipList<T>::dedup (line 893) ... ok
[INFO] [stdout] test src/ordered_skiplist.rs - ordered_skiplist::OrderedSkipList<T>::len (line 261) ... ok
[INFO] [stdout] test src/ordered_skiplist.rs - ordered_skiplist::OrderedSkipList<T>::range (line 1020) ... ok
[INFO] [stdout] test src/ordered_skiplist.rs - ordered_skiplist::OrderedSkipList<T>::iter (line 994) ... ok
[INFO] [stdout] test src/ordered_skiplist.rs - ordered_skiplist::OrderedSkipList<T>::is_empty (line 277) ... ok
[INFO] [stdout] test src/ordered_skiplist.rs - ordered_skiplist::OrderedSkipList<T>::get (line 432) ... ok
[INFO] [stdout] test src/ordered_skiplist.rs - ordered_skiplist::OrderedSkipList<T>::back (line 407) ... ok
[INFO] [stdout] test src/ordered_skiplist.rs - ordered_skiplist::OrderedSkipList<T>::front (line 383) ... ok
[INFO] [stdout] test src/ordered_skiplist.rs - ordered_skiplist::OrderedSkipList<T>::clear (line 235) ... ok
[INFO] [stdout] test src/ordered_skiplist.rs - ordered_skiplist::OrderedSkipList<T>::remove (line 555) ... ok
[INFO] [stdout] test src/ordered_skiplist.rs - ordered_skiplist::OrderedSkipList<T>::pop_front (line 456) ... ok
[INFO] [stdout] test src/ordered_skiplist.rs - ordered_skiplist::OrderedSkipList<T>::insert (line 295) ... ok
[INFO] [stdout] test src/ordered_skiplist.rs - ordered_skiplist::OrderedSkipList<T>::pop_back (line 481) ... ok
[INFO] [stdout] test src/ordered_skiplist.rs - ordered_skiplist::OrderedSkipList<T>::into_iter (line 971) ... ok
[INFO] [stdout] test src/ordered_skiplist.rs - ordered_skiplist::OrderedSkipList<T>::contains (line 506) ... ok
[INFO] [stdout] test src/ordered_skiplist.rs - ordered_skiplist::OrderedSkipList<T>::new (line 69) ... ok
[INFO] [stdout] test src/skiplist.rs - skiplist::SkipList<T>::contains (line 791) ... ok
[INFO] [stdout] test src/ordered_skiplist.rs - ordered_skiplist::OrderedSkipList<T>::with_comp (line 146) ... ok
[INFO] [stdout] test src/ordered_skiplist.rs - ordered_skiplist::OrderedSkipList<T>::retain (line 827) ... ok
[INFO] [stdout] test src/skiplist.rs - skiplist::SkipList<T>::get (line 365) ... ok
[INFO] [stdout] test src/skiplist.rs - skiplist::SkipList<T>::back (line 315) ... ok
[INFO] [stdout] test src/skiplist.rs - skiplist::SkipList<T>::dedup (line 816) ... ok
[INFO] [stdout] test src/ordered_skiplist.rs - ordered_skiplist::OrderedSkipList<T>::with_capacity (line 102) ... ok
[INFO] [stdout] test src/ordered_skiplist.rs - ordered_skiplist::OrderedSkipList<T>::remove_first (line 659) ... ok
[INFO] [stdout] test src/ordered_skiplist.rs - ordered_skiplist::OrderedSkipList<T>::remove_index (line 769) ... ok
[INFO] [stdout] test src/skiplist.rs - skiplist::SkipList<T>::front (line 267) ... ok
[INFO] [stdout] test src/skiplist.rs - skiplist::SkipList<T>::get_mut (line 389) ... ok
[INFO] [stdout] test src/skiplist.rs - skiplist::SkipList<T>::back_mut (line 340) ... ok
[INFO] [stdout] test src/skiplist.rs - skiplist::SkipList<T>::clear (line 81) ... ok
[INFO] [stdout] test src/skiplist.rs - skiplist::SkipList<T>::insert (line 146) ... ok
[INFO] [stdout] test src/skiplist.rs - skiplist::SkipList<T>::front_mut (line 291) ... ok
[INFO] [stdout] test src/skiplist.rs - skiplist::SkipList<T>::into_iter (line 593) ... ok
[INFO] [stdout] test src/skiplist.rs - skiplist::SkipList<T>::is_empty (line 123) ... ok
[INFO] [stdout] test src/skiplist.rs - skiplist::SkipList<T>::iter_mut (line 638) ... ok
[INFO] [stdout] test src/skiplist.rs - skiplist::SkipList<T>::len (line 107) ... ok
[INFO] [stdout] test src/skiplist.rs - skiplist::SkipList<T>::iter (line 616) ... ok
[INFO] [stdout] test src/skiplist.rs - skiplist::SkipList<T>::push_front (line 235) ... ok
[INFO] [stdout] test src/skiplist.rs - skiplist::SkipList<T>::new (line 38) ... ok
[INFO] [stdout] test src/skiplist.rs - skiplist::SkipList<T>::push_back (line 250) ... ok
[INFO] [stdout] test src/skiplist.rs - skiplist::SkipList<T>::range_mut (line 727) ... ok
[INFO] [stdout] test src/skiplist.rs - skiplist::SkipList<T>::pop_back (line 442) ... ok
[INFO] [stdout] test src/skiplist.rs - skiplist::SkipList<T>::retain (line 528) ... ok
[INFO] [stdout] test src/skiplist.rs - skiplist::SkipList<T>::range (line 664) ... ok
[INFO] [stdout] test src/skiplist.rs - skiplist::SkipList<T>::remove (line 471) ... ok
[INFO] [stdout] test src/skiplist.rs - skiplist::SkipList<T>::pop_front (line 417) ... ok
[INFO] [stdout] test src/skipmap.rs - skipmap::SkipMap<K, V>::back_mut (line 453) ... ok
[INFO] [stdout] test src/skipmap.rs - skipmap::SkipMap<K, V>::clear (line 295) ... ok
[INFO] [stdout] test src/skipmap.rs - skipmap::SkipMap<K, V>::contains_key (line 628) ... ok
[INFO] [stdout] test src/skiplist.rs - skiplist::SkipList<T>::with_capacity (line 60) ... ok
[INFO] [stdout] test src/skipmap.rs - skipmap::SkipMap<K, V>::back (line 419) ... ok
[INFO] [stdout] test src/skipmap.rs - skipmap::SkipMap<K, V>::into_iter (line 838) ... ok
[INFO] [stdout] test src/skipmap.rs - skipmap::SkipMap<K, V>::is_empty (line 337) ... ok
[INFO] [stdout] test src/skipmap.rs - skipmap::SkipMap<K, V>::front (line 356) ... ok
[INFO] [stdout] test src/skipmap.rs - skipmap::SkipMap<K, V>::get_mut (line 529) ... ok
[INFO] [stdout] test src/skipmap.rs - skipmap::SkipMap<K, V>::front_mut (line 389) ... ok
[INFO] [stdout] test src/skipmap.rs - skipmap::SkipMap<K, V>::insert (line 180) ... ok
[INFO] [stdout] test src/skipmap.rs - skipmap::SkipMap<K, V>::keys (line 909) ... ok
[INFO] [stdout] test src/skipmap.rs - skipmap::SkipMap<K, V>::iter (line 861) ... ok
[INFO] [stdout] test src/skipmap.rs - skipmap::SkipMap<K, V>::iter_mut (line 886) ... ok
[INFO] [stdout] test src/skipmap.rs - skipmap::SkipMap<K, V>::pop_back (line 603) ... ok
[INFO] [stdout] test src/skipmap.rs - skipmap::SkipMap<K, V>::get (line 484) ... ok
[INFO] [stdout] test src/skipmap.rs - skipmap::SkipMap<K, V>::values (line 931) ... ok
[INFO] [stdout] test src/skipmap.rs - skipmap::SkipMap<K, V>::remove (line 674) ... ok
[INFO] [stdout] test src/skipmap.rs - skipmap::SkipMap<K, V>::pop_front (line 578) ... ok
[INFO] [stdout] test src/skipmap.rs - skipmap::SkipMap<K, V>::new (line 137) ... ok
[INFO] [stdout] test src/skipmap.rs - skipmap::SkipMap<K, V>::len (line 321) ... ok
[INFO] [stdout] test src/skipmap.rs - skipmap::SkipMap<K, V>::remove_index (line 784) ... ok
[INFO] [stdout] test src/skipmap.rs - skipmap::SkipMap<K, V>::range (line 957) ... ok
[INFO] [stdout] test src/skipmap.rs - skipmap::SkipMap<K, V>::with_capacity (line 159) ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 69 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "faafbcebe8b8937d9ad5d91149ce80a335a95b13b7bfe7e8b684e289488af5a9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "faafbcebe8b8937d9ad5d91149ce80a335a95b13b7bfe7e8b684e289488af5a9", kill_on_drop: false }`
[INFO] [stdout] faafbcebe8b8937d9ad5d91149ce80a335a95b13b7bfe7e8b684e289488af5a9
