[INFO] fetching crate dancing-links 0.2.0...
[INFO] testing dancing-links-0.2.0 against master#a77da2d454e6caa227a85b16410b95f93495e7e0 for pr-91031
[INFO] extracting crate dancing-links 0.2.0 into /workspace/builds/worker-57/source
[INFO] validating manifest of crates.io crate dancing-links 0.2.0 on toolchain a77da2d454e6caa227a85b16410b95f93495e7e0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+a77da2d454e6caa227a85b16410b95f93495e7e0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate dancing-links 0.2.0
[INFO] finished tweaking crates.io crate dancing-links 0.2.0
[INFO] tweaked toml for crates.io crate dancing-links 0.2.0 written to /workspace/builds/worker-57/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+a77da2d454e6caa227a85b16410b95f93495e7e0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+a77da2d454e6caa227a85b16410b95f93495e7e0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-57/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-57/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@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+a77da2d454e6caa227a85b16410b95f93495e7e0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] c469cbb787fc6aa54029afd3a874746522f0840aac948865448ce7169b7dcd9b
[INFO] running `Command { std: "docker" "start" "-a" "c469cbb787fc6aa54029afd3a874746522f0840aac948865448ce7169b7dcd9b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c469cbb787fc6aa54029afd3a874746522f0840aac948865448ce7169b7dcd9b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c469cbb787fc6aa54029afd3a874746522f0840aac948865448ce7169b7dcd9b", kill_on_drop: false }`
[INFO] [stdout] c469cbb787fc6aa54029afd3a874746522f0840aac948865448ce7169b7dcd9b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-57/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-57/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@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+a77da2d454e6caa227a85b16410b95f93495e7e0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] ae7d823491b11c8c1cee32b7269703746910212aa51949ebbc61f5b2cd8f27a9
[INFO] running `Command { std: "docker" "start" "-a" "ae7d823491b11c8c1cee32b7269703746910212aa51949ebbc61f5b2cd8f27a9", kill_on_drop: false }`
[INFO] [stderr]    Compiling bumpalo v3.8.0
[INFO] [stderr]    Compiling dancing-links v0.2.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: field is never read: `min_column`
[INFO] [stdout]   --> src/solver.rs:29:5
[INFO] [stdout]    |
[INFO] [stdout] 29 |     min_column: *mut Column,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 2.14s
[INFO] running `Command { std: "docker" "inspect" "ae7d823491b11c8c1cee32b7269703746910212aa51949ebbc61f5b2cd8f27a9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ae7d823491b11c8c1cee32b7269703746910212aa51949ebbc61f5b2cd8f27a9", kill_on_drop: false }`
[INFO] [stdout] ae7d823491b11c8c1cee32b7269703746910212aa51949ebbc61f5b2cd8f27a9
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-57/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-57/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@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+a77da2d454e6caa227a85b16410b95f93495e7e0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 86408dd4ffa5117d3334ba00f5e9a8c86bdb19d9f29b3b81ad79675efda78d6b
[INFO] running `Command { std: "docker" "start" "-a" "86408dd4ffa5117d3334ba00f5e9a8c86bdb19d9f29b3b81ad79675efda78d6b", kill_on_drop: false }`
[INFO] [stderr]    Compiling dancing-links v0.2.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: field is never read: `min_column`
[INFO] [stdout]   --> src/solver.rs:29:5
[INFO] [stdout]    |
[INFO] [stdout] 29 |     min_column: *mut Column,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `min_column`
[INFO] [stdout]   --> src/solver.rs:29:5
[INFO] [stdout]    |
[INFO] [stdout] 29 |     min_column: *mut Column,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 2.05s
[INFO] running `Command { std: "docker" "inspect" "86408dd4ffa5117d3334ba00f5e9a8c86bdb19d9f29b3b81ad79675efda78d6b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "86408dd4ffa5117d3334ba00f5e9a8c86bdb19d9f29b3b81ad79675efda78d6b", kill_on_drop: false }`
[INFO] [stdout] 86408dd4ffa5117d3334ba00f5e9a8c86bdb19d9f29b3b81ad79675efda78d6b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-57/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-57/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@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+a77da2d454e6caa227a85b16410b95f93495e7e0" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 883776fda9473d83fb01945ef7e21c97a2db3fc304b707665109cd7ad2e4d643
[INFO] running `Command { std: "docker" "start" "-a" "883776fda9473d83fb01945ef7e21c97a2db3fc304b707665109cd7ad2e4d643", kill_on_drop: false }`
[INFO] [stderr] warning: field is never read: `min_column`
[INFO] [stdout] 
[INFO] [stderr]   --> src/solver.rs:29:5
[INFO] [stdout] running 19 tests
[INFO] [stderr]    |
[INFO] [stderr] 29 |     min_column: *mut Column,
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: `dancing-links` (lib) generated 1 warning
[INFO] [stderr] warning: `dancing-links` (lib test) generated 1 warning (1 duplicate)
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.01s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/dancing_links-a205ea8346af7a0e)
[INFO] [stdout] test grid::tests::cover_uncover_column ... ok
[INFO] [stdout] test grid::tests::cover_uncover_all ... ok
[INFO] [stdout] test grid::tests::create_a_small_grid ... ok
[INFO] [stdout] test grid::tests::latin_square_cover_1 ... ok
[INFO] [stdout] test grid::tests::create_weird_grids ... ok
[INFO] [stdout] test latin_square::tests::check_all_possibilities ... ok
[INFO] [stdout] test latin_square::tests::check_generated_possibilities_constraints ... ok
[INFO] [stdout] test latin_square::tests::solve_impossible_latin_square ... ok
[INFO] [stdout] test queens::tests::check_diagonal_indices ... ok
[INFO] [stdout] test latin_square::tests::solve_multi_solution_latin_square ... ok
[INFO] [stdout] test latin_square::tests::solve_small_latin_square ... ok
[INFO] [stdout] test queens::tests::check_small_board ... ok
[INFO] [stdout] test util::tests::latin_square_test_1 ... ok
[INFO] [stdout] test queens::tests::check_tiny_boards ... ok
[INFO] [stdout] test sudoku::tests::check_generated_possibilities_constraints ... ok
[INFO] [stdout] test util::tests::latin_square_test_3 ... ok
[INFO] [stdout] test util::tests::three_combo ... ok
[INFO] [stdout] test sudoku::tests::solve_small_sudoku ... ok
[INFO] [stdout] test queens::tests::count_medium_board ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 19 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.04s
[INFO] [stdout] 
[INFO] [stderr]    Doc-tests dancing-links
[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" "883776fda9473d83fb01945ef7e21c97a2db3fc304b707665109cd7ad2e4d643", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "883776fda9473d83fb01945ef7e21c97a2db3fc304b707665109cd7ad2e4d643", kill_on_drop: false }`
[INFO] [stdout] 883776fda9473d83fb01945ef7e21c97a2db3fc304b707665109cd7ad2e4d643