[INFO] fetching crate skiplist 0.3.0...
[INFO] testing skiplist-0.3.0 against master#99e3aef02079e9c10583638520cd0c134dc3a01d for pr-85530
[INFO] extracting crate skiplist 0.3.0 into /workspace/builds/worker-2/source
[INFO] validating manifest of crates.io crate skiplist 0.3.0 on toolchain 99e3aef02079e9c10583638520cd0c134dc3a01d
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+99e3aef02079e9c10583638520cd0c134dc3a01d" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", 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-2/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+99e3aef02079e9c10583638520cd0c134dc3a01d" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+99e3aef02079e9c10583638520cd0c134dc3a01d" "fetch" "--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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+99e3aef02079e9c10583638520cd0c134dc3a01d" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e3fbf46ef7390f0f48d476313d5c60da1085337a05810b7fe4800b41ad85d4f8
[INFO] running `Command { std: "docker" "start" "-a" "e3fbf46ef7390f0f48d476313d5c60da1085337a05810b7fe4800b41ad85d4f8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e3fbf46ef7390f0f48d476313d5c60da1085337a05810b7fe4800b41ad85d4f8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e3fbf46ef7390f0f48d476313d5c60da1085337a05810b7fe4800b41ad85d4f8", kill_on_drop: false }`
[INFO] [stdout] e3fbf46ef7390f0f48d476313d5c60da1085337a05810b7fe4800b41ad85d4f8
[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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+99e3aef02079e9c10583638520cd0c134dc3a01d" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c96b10e672a8929729c572dad4386a8558784952f2927bbe05a54418da67da73
[INFO] running `Command { std: "docker" "start" "-a" "c96b10e672a8929729c572dad4386a8558784952f2927bbe05a54418da67da73", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.95
[INFO] [stderr]    Compiling cfg-if v1.0.0
[INFO] [stderr]    Compiling getrandom v0.1.16
[INFO] [stderr]    Compiling rand_core v0.5.1
[INFO] [stderr]    Compiling rand_chacha v0.2.2
[INFO] [stderr]    Compiling rand_pcg v0.2.1
[INFO] [stderr]    Compiling rand v0.7.3
[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 4.23s
[INFO] running `Command { std: "docker" "inspect" "c96b10e672a8929729c572dad4386a8558784952f2927bbe05a54418da67da73", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c96b10e672a8929729c572dad4386a8558784952f2927bbe05a54418da67da73", kill_on_drop: false }`
[INFO] [stdout] c96b10e672a8929729c572dad4386a8558784952f2927bbe05a54418da67da73
[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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+99e3aef02079e9c10583638520cd0c134dc3a01d" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 2b5b54e42860bb6f7a0847788c323b07016364f8679f257490dc2b5701d22f87
[INFO] running `Command { std: "docker" "start" "-a" "2b5b54e42860bb6f7a0847788c323b07016364f8679f257490dc2b5701d22f87", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v1.0.1
[INFO] [stderr]    Compiling lazy_static v1.4.0
[INFO] [stderr]    Compiling crossbeam-utils v0.8.5
[INFO] [stderr]    Compiling ryu v1.0.5
[INFO] [stderr]    Compiling proc-macro2 v1.0.27
[INFO] [stderr]    Compiling crossbeam-epoch v0.9.5
[INFO] [stderr]    Compiling unicode-xid v0.2.2
[INFO] [stderr]    Compiling either v1.6.1
[INFO] [stderr]    Compiling rayon-core v1.9.1
[INFO] [stderr]    Compiling syn v1.0.72
[INFO] [stderr]    Compiling bitflags v1.2.1
[INFO] [stderr]    Compiling serde_json v1.0.64
[INFO] [stderr]    Compiling unicode-width v0.1.8
[INFO] [stderr]    Compiling serde_derive v1.0.126
[INFO] [stderr]    Compiling num_cpus v1.13.0
[INFO] [stderr]    Compiling atty v0.2.14
[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 textwrap v0.11.0
[INFO] [stderr]    Compiling bstr v0.2.16
[INFO] [stderr]    Compiling itertools v0.9.0
[INFO] [stderr]    Compiling itertools v0.10.0
[INFO] [stderr]    Compiling memoffset v0.6.4
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling rayon v1.5.1
[INFO] [stderr]    Compiling clap v2.33.3
[INFO] [stderr]    Compiling crossbeam-channel v0.5.1
[INFO] [stderr]    Compiling csv v1.1.6
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]    Compiling crossbeam-deque v0.8.0
[INFO] [stderr]    Compiling criterion-plot v0.4.3
[INFO] [stderr]    Compiling tinytemplate v1.2.1
[INFO] [stderr]    Compiling plotters v0.3.1
[INFO] [stderr]    Compiling criterion v0.3.4
[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 29.65s
[INFO] running `Command { std: "docker" "inspect" "2b5b54e42860bb6f7a0847788c323b07016364f8679f257490dc2b5701d22f87", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2b5b54e42860bb6f7a0847788c323b07016364f8679f257490dc2b5701d22f87", kill_on_drop: false }`
[INFO] [stdout] 2b5b54e42860bb6f7a0847788c323b07016364f8679f257490dc2b5701d22f87
[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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+99e3aef02079e9c10583638520cd0c134dc3a01d" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] bd445f83380ce3ba2be578ee2919eac644ae0e0acef7adbb718796710ec796f0
[INFO] running `Command { std: "docker" "start" "-a" "bd445f83380ce3ba2be578ee2919eac644ae0e0acef7adbb718796710ec796f0", 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 0.15s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/skiplist-f2d5b1c21912bb8b)
[INFO] [stdout] 
[INFO] [stdout] running 58 tests
[INFO] [stdout] test level_generator::tests::new ... ok
[INFO] [stdout] test ordered_skiplist::tests::contains ... ok
[INFO] [stdout] test ordered_skiplist::tests::basic_small ... ok
[INFO] [stdout] test ordered_skiplist::tests::clear ... ok
[INFO] [stdout] test ordered_skiplist::tests::debug_display ... 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::equality ... ok
[INFO] [stdout] test skiplist::tests::contains ... ok
[INFO] [stdout] test skiplist::tests::equality ... ok
[INFO] [stdout] test skiplist::tests::clear ... ok
[INFO] [stdout] test skiplist::tests::basic_small ... ok
[INFO] [stdout] test ordered_skiplist::tests::range_1000 ... ok
[INFO] [stdout] test level_generator::tests::invalid_p_0 ... ok
[INFO] [stdout] test skiplist::tests::debug_display ... ok
[INFO] [stdout] test skipmap::tests::basic_small ... ok
[INFO] [stdout] test skipmap::tests::clear ... ok
[INFO] [stdout] test skipmap::tests::debug_display ... ok
[INFO] [stdout] test level_generator::tests::invalid_p_1 ... ok
[INFO] [stdout] test skiplist::tests::range_mut_1000 ... ok
[INFO] [stdout] test skipmap::tests::contains ... ok
[INFO] [stdout] test ordered_skiplist::tests::remove_index ... ok
[INFO] [stdout] test ordered_skiplist::tests::remove ... ok
[INFO] [stdout] test skipmap::tests::equality ... ok
[INFO] [stdout] test skipmap::tests::insert_existing ... ok
[INFO] [stdout] test skipmap::tests::iter_key_val ... ok
[INFO] [stdout] test level_generator::tests::invalid_total ... ok
[INFO] [stdout] test skiplist::tests::range_1000 ... ok
[INFO] [stdout] test skiplist::tests::range_small ... ok
[INFO] [stdout] test ordered_skiplist::tests::index_pop ... ok
[INFO] [stdout] test skipmap::tests::range_small ... ok
[INFO] [stdout] test ordered_skiplist::tests::with_comp ... ok
[INFO] [stdout] test skiplist::tests::inplace_mut ... ok
[INFO] [stdout] test skipmap::tests::iter_mixed ... ok
[INFO] [stdout] test skipmap::tests::range_1000 ... ok
[INFO] [stdout] test skipmap::tests::index_pop ... ok
[INFO] [stdout] test skiplist::tests::index_pop ... ok
[INFO] [stdout] test skipmap::tests::iter_rev ... ok
[INFO] [stdout] test skipmap::tests::remove_index ... ok
[INFO] [stdout] test ordered_skiplist::tests::sort_by_panic ... ok
[INFO] [stdout] test ordered_skiplist::tests::iter_rev ... ok
[INFO] [stdout] test skiplist::tests::retain ... ok
[INFO] [stdout] test skiplist::tests::iter_mixed ... ok
[INFO] [stdout] test ordered_skiplist::tests::iter_mixed ... ok
[INFO] [stdout] test ordered_skiplist::tests::iter ... ok
[INFO] [stdout] test skiplist::tests::iter_rev ... ok
[INFO] [stdout] test skiplist::tests::iter ... ok
[INFO] [stdout] test skipmap::tests::iter ... ok
[INFO] [stdout] test ordered_skiplist::tests::retain ... ok
[INFO] [stdout] test ordered_skiplist::tests::basic_large ... ok
[INFO] [stdout] test ordered_skiplist::tests::pop ... ok
[INFO] [stdout] test skipmap::tests::basic_large ... ok
[INFO] [stdout] test ordered_skiplist::tests::range ... 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 skiplist::tests::dedup ... ok
[INFO] [stdout] test ordered_skiplist::tests::dedup ... ok
[INFO] [stdout] 
[INFO] [stderr]    Doc-tests skiplist
[INFO] [stdout] test result: ok. 58 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 5.64s
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] running 69 tests
[INFO] [stderr] error: test failed, to rerun pass '--doc'
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name skiplist --test /opt/rustwide/workdir/src/lib.rs -L dependency=/opt/rustwide/target/debug/deps -L dependency=/opt/rustwide/target/debug/deps --extern criterion=/opt/rustwide/target/debug/deps/libcriterion-53096bde734cebfd.rlib --extern rand=/opt/rustwide/target/debug/deps/librand-1cbd57bd2abbd0d7.rlib --extern skiplist=/opt/rustwide/target/debug/deps/libskiplist-02440dcda77506ab.rlib -C embed-bitcode=no --error-format human` (signal: 9, SIGKILL: kill)
[INFO] running `Command { std: "docker" "inspect" "bd445f83380ce3ba2be578ee2919eac644ae0e0acef7adbb718796710ec796f0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bd445f83380ce3ba2be578ee2919eac644ae0e0acef7adbb718796710ec796f0", kill_on_drop: false }`
[INFO] [stdout] bd445f83380ce3ba2be578ee2919eac644ae0e0acef7adbb718796710ec796f0