[INFO] fetching crate dagre_rust 0.0.5...
[INFO] testing dagre_rust-0.0.5 against 1.69.0 for beta-1.70-1
[INFO] extracting crate dagre_rust 0.0.5 into /workspace/builds/worker-3-tc1/source
[INFO] validating manifest of crates.io crate dagre_rust 0.0.5 on toolchain 1.69.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.69.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate dagre_rust 0.0.5
[INFO] finished tweaking crates.io crate dagre_rust 0.0.5
[INFO] tweaked toml for crates.io crate dagre_rust 0.0.5 written to /workspace/builds/worker-3-tc1/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" __CARGO_TEST_CHANNEL_OVERRIDE_DO_NOT_USE_THIS="nightly" "/workspace/cargo-home/bin/cargo" "+1.69.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.69.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded graphlib_rust v0.0.2
[INFO] [stderr]   Downloaded ordered_hashmap v0.0.3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/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@sha256:5ff2268d62e97bff2cde7d5815dd6ed5b47097566f13b8d0ca110b04b60e07ed" "/opt/rustwide/cargo-home/bin/cargo" "+1.69.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 8ecce10c8d36ad9513ffadce017db612f74cdea5e6632359affbbf2cfd862457
[INFO] running `Command { std: "docker" "start" "-a" "8ecce10c8d36ad9513ffadce017db612f74cdea5e6632359affbbf2cfd862457", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "8ecce10c8d36ad9513ffadce017db612f74cdea5e6632359affbbf2cfd862457", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8ecce10c8d36ad9513ffadce017db612f74cdea5e6632359affbbf2cfd862457", kill_on_drop: false }`
[INFO] [stdout] 8ecce10c8d36ad9513ffadce017db612f74cdea5e6632359affbbf2cfd862457
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/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" "RUSTDOCFLAGS=--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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:5ff2268d62e97bff2cde7d5815dd6ed5b47097566f13b8d0ca110b04b60e07ed" "/opt/rustwide/cargo-home/bin/cargo" "+1.69.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 43fadc988a7c652d16b8836a20dc45abf5367881220cd1cf4a7b7d93583051a2
[INFO] running `Command { std: "docker" "start" "-a" "43fadc988a7c652d16b8836a20dc45abf5367881220cd1cf4a7b7d93583051a2", kill_on_drop: false }`
[INFO] [stderr]    Compiling ordered_hashmap v0.0.3
[INFO] [stderr]    Compiling graphlib_rust v0.0.2
[INFO] [stderr]    Compiling dagre_rust v0.0.5 (/opt/rustwide/workdir)
[INFO] [stdout] warning: value assigned to `edge` is never read
[INFO] [stdout]   --> src/layout/rank/feasible_tree.rs:43:11
[INFO] [stdout]    |
[INFO] [stdout] 43 |   let mut edge: Option<Edge> = None;
[INFO] [stdout]    |           ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: maybe it is overwritten before being read?
[INFO] [stdout]    = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `delta` is never read
[INFO] [stdout]   --> src/layout/rank/feasible_tree.rs:44:11
[INFO] [stdout]    |
[INFO] [stdout] 44 |   let mut delta: Option<i32> = None;
[INFO] [stdout]    |           ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `e`
[INFO] [stdout]    --> src/layout/rank/feasible_tree.rs:104:15
[INFO] [stdout]     |
[INFO] [stdout] 104 |     .filter(|(e, e_)| e_.is_some())
[INFO] [stdout]     |               ^ help: if this is intentional, prefix it with an underscore: `_e`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `e1`
[INFO] [stdout]    --> src/layout/rank/feasible_tree.rs:105:15
[INFO] [stdout]     |
[INFO] [stdout] 105 |     .min_by(|(e1, e1_), (e2, e2_)| {
[INFO] [stdout]     |               ^^ help: if this is intentional, prefix it with an underscore: `_e1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `e2`
[INFO] [stdout]    --> src/layout/rank/feasible_tree.rs:105:26
[INFO] [stdout]     |
[INFO] [stdout] 105 |     .min_by(|(e1, e1_), (e2, e2_)| {
[INFO] [stdout]     |                          ^^ help: if this is intentional, prefix it with an underscore: `_e2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable `prev_north_pos` is assigned to, but never used
[INFO] [stdout]    --> src/layout/position/bk.rs:107:13
[INFO] [stdout]     |
[INFO] [stdout] 107 |     let mut prev_north_pos = -1;
[INFO] [stdout]     |             ^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: consider using `_prev_north_pos` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `prev_north_pos` is never read
[INFO] [stdout]    --> src/layout/position/bk.rs:123:15
[INFO] [stdout]     |
[INFO] [stdout] 123 |               prev_north_pos = next_north_pos.clone();
[INFO] [stdout]     |               ^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `delta` is never read
[INFO] [stdout]    --> src/layout/position/bk.rs:586:5
[INFO] [stdout]     |
[INFO] [stdout] 586 |     delta = 0.0;
[INFO] [stdout]     |     ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 8 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.55s
[INFO] running `Command { std: "docker" "inspect" "43fadc988a7c652d16b8836a20dc45abf5367881220cd1cf4a7b7d93583051a2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "43fadc988a7c652d16b8836a20dc45abf5367881220cd1cf4a7b7d93583051a2", kill_on_drop: false }`
[INFO] [stdout] 43fadc988a7c652d16b8836a20dc45abf5367881220cd1cf4a7b7d93583051a2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/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" "RUSTDOCFLAGS=--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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:5ff2268d62e97bff2cde7d5815dd6ed5b47097566f13b8d0ca110b04b60e07ed" "/opt/rustwide/cargo-home/bin/cargo" "+1.69.0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a4780598ab57c673ea7b179d46f0aecd1729a436ab5d79f63ca42d530c58fb6f
[INFO] running `Command { std: "docker" "start" "-a" "a4780598ab57c673ea7b179d46f0aecd1729a436ab5d79f63ca42d530c58fb6f", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stdout] warning: value assigned to `edge` is never read
[INFO] [stdout]   --> src/layout/rank/feasible_tree.rs:43:11
[INFO] [stdout]    |
[INFO] [stdout] 43 |   let mut edge: Option<Edge> = None;
[INFO] [stdout]    |           ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: maybe it is overwritten before being read?
[INFO] [stdout]    = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `delta` is never read
[INFO] [stdout]   --> src/layout/rank/feasible_tree.rs:44:11
[INFO] [stdout]    |
[INFO] [stdout] 44 |   let mut delta: Option<i32> = None;
[INFO] [stdout]    |           ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `e`
[INFO] [stdout]    --> src/layout/rank/feasible_tree.rs:104:15
[INFO] [stdout]     |
[INFO] [stdout] 104 |     .filter(|(e, e_)| e_.is_some())
[INFO] [stdout]     |               ^ help: if this is intentional, prefix it with an underscore: `_e`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `e1`
[INFO] [stdout]    --> src/layout/rank/feasible_tree.rs:105:15
[INFO] [stdout]     |
[INFO] [stdout] 105 |     .min_by(|(e1, e1_), (e2, e2_)| {
[INFO] [stdout]     |               ^^ help: if this is intentional, prefix it with an underscore: `_e1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `e2`
[INFO] [stdout]    --> src/layout/rank/feasible_tree.rs:105:26
[INFO] [stdout]     |
[INFO] [stdout] 105 |     .min_by(|(e1, e1_), (e2, e2_)| {
[INFO] [stdout]     |                          ^^ help: if this is intentional, prefix it with an underscore: `_e2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable `prev_north_pos` is assigned to, but never used
[INFO] [stdout]    --> src/layout/position/bk.rs:107:13
[INFO] [stdout]     |
[INFO] [stdout] 107 |     let mut prev_north_pos = -1;
[INFO] [stdout]     |             ^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: consider using `_prev_north_pos` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling dagre_rust v0.0.5 (/opt/rustwide/workdir)
[INFO] [stdout] warning: value assigned to `prev_north_pos` is never read
[INFO] [stdout]    --> src/layout/position/bk.rs:123:15
[INFO] [stdout]     |
[INFO] [stdout] 123 |               prev_north_pos = next_north_pos.clone();
[INFO] [stdout]     |               ^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `delta` is never read
[INFO] [stdout]    --> src/layout/position/bk.rs:586:5
[INFO] [stdout]     |
[INFO] [stdout] 586 |     delta = 0.0;
[INFO] [stdout]     |     ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 8 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `edge` is never read
[INFO] [stdout]   --> src/layout/rank/feasible_tree.rs:43:11
[INFO] [stdout]    |
[INFO] [stdout] 43 |   let mut edge: Option<Edge> = None;
[INFO] [stdout]    |           ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: maybe it is overwritten before being read?
[INFO] [stdout]    = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `delta` is never read
[INFO] [stdout]   --> src/layout/rank/feasible_tree.rs:44:11
[INFO] [stdout]    |
[INFO] [stdout] 44 |   let mut delta: Option<i32> = None;
[INFO] [stdout]    |           ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `e`
[INFO] [stdout]    --> src/layout/rank/feasible_tree.rs:104:15
[INFO] [stdout]     |
[INFO] [stdout] 104 |     .filter(|(e, e_)| e_.is_some())
[INFO] [stdout]     |               ^ help: if this is intentional, prefix it with an underscore: `_e`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `e1`
[INFO] [stdout]    --> src/layout/rank/feasible_tree.rs:105:15
[INFO] [stdout]     |
[INFO] [stdout] 105 |     .min_by(|(e1, e1_), (e2, e2_)| {
[INFO] [stdout]     |               ^^ help: if this is intentional, prefix it with an underscore: `_e1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `e2`
[INFO] [stdout]    --> src/layout/rank/feasible_tree.rs:105:26
[INFO] [stdout]     |
[INFO] [stdout] 105 |     .min_by(|(e1, e1_), (e2, e2_)| {
[INFO] [stdout]     |                          ^^ help: if this is intentional, prefix it with an underscore: `_e2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable `prev_north_pos` is assigned to, but never used
[INFO] [stdout]    --> src/layout/position/bk.rs:107:13
[INFO] [stdout]     |
[INFO] [stdout] 107 |     let mut prev_north_pos = -1;
[INFO] [stdout]     |             ^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: consider using `_prev_north_pos` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `prev_north_pos` is never read
[INFO] [stdout]    --> src/layout/position/bk.rs:123:15
[INFO] [stdout]     |
[INFO] [stdout] 123 |               prev_north_pos = next_north_pos.clone();
[INFO] [stdout]     |               ^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `delta` is never read
[INFO] [stdout]    --> src/layout/position/bk.rs:586:5
[INFO] [stdout]     |
[INFO] [stdout] 586 |     delta = 0.0;
[INFO] [stdout]     |     ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 8 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.79s
[INFO] running `Command { std: "docker" "inspect" "a4780598ab57c673ea7b179d46f0aecd1729a436ab5d79f63ca42d530c58fb6f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a4780598ab57c673ea7b179d46f0aecd1729a436ab5d79f63ca42d530c58fb6f", kill_on_drop: false }`
[INFO] [stdout] a4780598ab57c673ea7b179d46f0aecd1729a436ab5d79f63ca42d530c58fb6f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/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" "RUSTDOCFLAGS=--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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:5ff2268d62e97bff2cde7d5815dd6ed5b47097566f13b8d0ca110b04b60e07ed" "/opt/rustwide/cargo-home/bin/cargo" "+1.69.0" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] f5c653f729c49e24fb3404c463b5535e692f3a8da3db3fd39ee0e53b399d6798
[INFO] running `Command { std: "docker" "start" "-a" "f5c653f729c49e24fb3404c463b5535e692f3a8da3db3fd39ee0e53b399d6798", kill_on_drop: false }`
[INFO] [stderr] warning: value assigned to `edge` is never read
[INFO] [stderr]   --> src/layout/rank/feasible_tree.rs:43:11
[INFO] [stderr]    |
[INFO] [stderr] 43 |   let mut edge: Option<Edge> = None;
[INFO] [stderr]    |           ^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = help: maybe it is overwritten before being read?
[INFO] [stderr]    = note: `#[warn(unused_assignments)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: value assigned to `delta` is never read
[INFO] [stderr]   --> src/layout/rank/feasible_tree.rs:44:11
[INFO] [stderr]    |
[INFO] [stderr] 44 |   let mut delta: Option<i32> = None;
[INFO] [stderr]    |           ^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = help: maybe it is overwritten before being read?
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `e`
[INFO] [stderr]    --> src/layout/rank/feasible_tree.rs:104:15
[INFO] [stderr]     |
[INFO] [stderr] 104 |     .filter(|(e, e_)| e_.is_some())
[INFO] [stderr]     |               ^ help: if this is intentional, prefix it with an underscore: `_e`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `e1`
[INFO] [stderr]    --> src/layout/rank/feasible_tree.rs:105:15
[INFO] [stderr]     |
[INFO] [stderr] 105 |     .min_by(|(e1, e1_), (e2, e2_)| {
[INFO] [stderr]     |               ^^ help: if this is intentional, prefix it with an underscore: `_e1`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `e2`
[INFO] [stderr]    --> src/layout/rank/feasible_tree.rs:105:26
[INFO] [stderr]     |
[INFO] [stderr] 105 |     .min_by(|(e1, e1_), (e2, e2_)| {
[INFO] [stderr]     |                          ^^ help: if this is intentional, prefix it with an underscore: `_e2`
[INFO] [stderr] 
[INFO] [stderr] warning: variable `prev_north_pos` is assigned to, but never used
[INFO] [stderr]    --> src/layout/position/bk.rs:107:13
[INFO] [stderr]     |
[INFO] [stderr] 107 |     let mut prev_north_pos = -1;
[INFO] [stderr]     |             ^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: consider using `_prev_north_pos` instead
[INFO] [stderr] 
[INFO] [stderr] warning: value assigned to `prev_north_pos` is never read
[INFO] [stderr]    --> src/layout/position/bk.rs:123:15
[INFO] [stderr]     |
[INFO] [stderr] 123 |               prev_north_pos = next_north_pos.clone();
[INFO] [stderr]     |               ^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: maybe it is overwritten before being read?
[INFO] [stderr] 
[INFO] [stderr] warning: value assigned to `delta` is never read
[INFO] [stderr]    --> src/layout/position/bk.rs:586:5
[INFO] [stderr]     |
[INFO] [stderr] 586 |     delta = 0.0;
[INFO] [stderr]     |     ^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: maybe it is overwritten before being read?
[INFO] [stderr] 
[INFO] [stderr] warning: `dagre_rust` (lib) generated 8 warnings (run `cargo fix --lib -p dagre_rust` to apply 3 suggestions)
[INFO] [stderr] warning: `dagre_rust` (lib test) generated 8 warnings (8 duplicates)
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.00s
[INFO] [stderr]      Running unittests src/lib.rs (/opt/rustwide/target/debug/deps/dagre_rust-117886937cab7239)
[INFO] [stdout] 
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] [stderr]    Doc-tests dagre_rust
[INFO] [stdout] 
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "f5c653f729c49e24fb3404c463b5535e692f3a8da3db3fd39ee0e53b399d6798", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f5c653f729c49e24fb3404c463b5535e692f3a8da3db3fd39ee0e53b399d6798", kill_on_drop: false }`
[INFO] [stdout] f5c653f729c49e24fb3404c463b5535e692f3a8da3db3fd39ee0e53b399d6798
