[INFO] cloning repository https://github.com/queuedq/exact-cover-rs
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/queuedq/exact-cover-rs" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fqueuedq%2Fexact-cover-rs", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fqueuedq%2Fexact-cover-rs'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 4243e392d16ba44917ad6ffb5c3f6b1bafbd4774
[INFO] testing queuedq/exact-cover-rs against master#432e145bd5a974c5b6f4dd9b352891bd7502b69d for pr-87041
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fqueuedq%2Fexact-cover-rs" "/workspace/builds/worker-0/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/queuedq/exact-cover-rs on toolchain 432e145bd5a974c5b6f4dd9b352891bd7502b69d
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+432e145bd5a974c5b6f4dd9b352891bd7502b69d" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/queuedq/exact-cover-rs
[INFO] finished tweaking git repo https://github.com/queuedq/exact-cover-rs
[INFO] tweaked toml for git repo https://github.com/queuedq/exact-cover-rs written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] crate git repo https://github.com/queuedq/exact-cover-rs already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+432e145bd5a974c5b6f4dd9b352891bd7502b69d" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+432e145bd5a974c5b6f4dd9b352891bd7502b69d" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] cb1664378e51e5374b1ca150c8d9d574f8c0dbdbd98b90d637f74a07b7282478
[INFO] running `Command { std: "docker" "start" "-a" "cb1664378e51e5374b1ca150c8d9d574f8c0dbdbd98b90d637f74a07b7282478", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "cb1664378e51e5374b1ca150c8d9d574f8c0dbdbd98b90d637f74a07b7282478", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cb1664378e51e5374b1ca150c8d9d574f8c0dbdbd98b90d637f74a07b7282478", kill_on_drop: false }`
[INFO] [stdout] cb1664378e51e5374b1ca150c8d9d574f8c0dbdbd98b90d637f74a07b7282478
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+432e145bd5a974c5b6f4dd9b352891bd7502b69d" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 366cad0d6b04b777ea1ea9df1b3917b991ef0d91095a32ed873b7df4bb380ad9
[INFO] running `Command { std: "docker" "start" "-a" "366cad0d6b04b777ea1ea9df1b3917b991ef0d91095a32ed873b7df4bb380ad9", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.24
[INFO] [stderr]    Compiling unicode-xid v0.2.1
[INFO] [stderr]    Compiling syn v1.0.67
[INFO] [stderr]    Compiling futures-sink v0.3.13
[INFO] [stderr]    Compiling futures-core v0.3.13
[INFO] [stderr]    Compiling futures-task v0.3.13
[INFO] [stderr]    Compiling futures-io v0.3.13
[INFO] [stderr]    Compiling pin-project-lite v0.2.6
[INFO] [stderr]    Compiling indexmap v1.6.2
[INFO] [stderr]    Compiling futures-channel v0.3.13
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]    Compiling futures-macro v0.3.13
[INFO] [stderr]    Compiling futures-util v0.3.13
[INFO] [stderr]    Compiling futures-executor v0.3.13
[INFO] [stderr]    Compiling futures v0.3.13
[INFO] [stderr]    Compiling exact-cover v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variant is never constructed: `Aborted`
[INFO] [stdout]   --> src/solver.rs:30:5
[INFO] [stdout]    |
[INFO] [stdout] 30 |     Aborted(Matrix),
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `problem`
[INFO] [stdout]   --> src/solver.rs:35:5
[INFO] [stdout]    |
[INFO] [stdout] 35 |     problem: Problem<N, C>,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `thread`
[INFO] [stdout]    --> src/solver.rs:119:5
[INFO] [stdout]     |
[INFO] [stdout] 119 |     thread: JoinHandle<()>,
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `try_recv`
[INFO] [stdout]    --> src/solver.rs:179:12
[INFO] [stdout]     |
[INFO] [stdout] 179 |     pub fn try_recv(&self) -> Result<SolverThreadEvent, TryRecvError> {
[INFO] [stdout]     |            ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `join`
[INFO] [stdout]    --> src/solver.rs:187:12
[INFO] [stdout]     |
[INFO] [stdout] 187 |     pub fn join(self) -> ThreadResult<()> {
[INFO] [stdout]     |            ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 16.44s
[INFO] running `Command { std: "docker" "inspect" "366cad0d6b04b777ea1ea9df1b3917b991ef0d91095a32ed873b7df4bb380ad9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "366cad0d6b04b777ea1ea9df1b3917b991ef0d91095a32ed873b7df4bb380ad9", kill_on_drop: false }`
[INFO] [stdout] 366cad0d6b04b777ea1ea9df1b3917b991ef0d91095a32ed873b7df4bb380ad9
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+432e145bd5a974c5b6f4dd9b352891bd7502b69d" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] b60a23973519d2cf136739089a6420b33914d2f5a2210acc2594fcef5ab53767
[INFO] running `Command { std: "docker" "start" "-a" "b60a23973519d2cf136739089a6420b33914d2f5a2210acc2594fcef5ab53767", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stdout] warning: variant is never constructed: `Aborted`
[INFO] [stdout]   --> src/solver.rs:30:5
[INFO] [stdout]    |
[INFO] [stdout] 30 |     Aborted(Matrix),
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `problem`
[INFO] [stdout]   --> src/solver.rs:35:5
[INFO] [stdout]    |
[INFO] [stdout] 35 |     problem: Problem<N, C>,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling exact-cover v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: field is never read: `thread`
[INFO] [stdout]    --> src/solver.rs:119:5
[INFO] [stdout]     |
[INFO] [stdout] 119 |     thread: JoinHandle<()>,
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `try_recv`
[INFO] [stdout]    --> src/solver.rs:179:12
[INFO] [stdout]     |
[INFO] [stdout] 179 |     pub fn try_recv(&self) -> Result<SolverThreadEvent, TryRecvError> {
[INFO] [stdout]     |            ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `join`
[INFO] [stdout]    --> src/solver.rs:187:12
[INFO] [stdout]     |
[INFO] [stdout] 187 |     pub fn join(self) -> ThreadResult<()> {
[INFO] [stdout]     |            ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `super::*`
[INFO] [stdout]    --> src/dlx.rs:222:9
[INFO] [stdout]     |
[INFO] [stdout] 222 |     use super::*;
[INFO] [stdout]     |         ^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Aborted`
[INFO] [stdout]   --> src/solver.rs:30:5
[INFO] [stdout]    |
[INFO] [stdout] 30 |     Aborted(Matrix),
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `problem`
[INFO] [stdout]   --> src/solver.rs:35:5
[INFO] [stdout]    |
[INFO] [stdout] 35 |     problem: Problem<N, C>,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `thread`
[INFO] [stdout]    --> src/solver.rs:119:5
[INFO] [stdout]     |
[INFO] [stdout] 119 |     thread: JoinHandle<()>,
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `try_recv`
[INFO] [stdout]    --> src/solver.rs:179:12
[INFO] [stdout]     |
[INFO] [stdout] 179 |     pub fn try_recv(&self) -> Result<SolverThreadEvent, TryRecvError> {
[INFO] [stdout]     |            ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `join`
[INFO] [stdout]    --> src/solver.rs:187:12
[INFO] [stdout]     |
[INFO] [stdout] 187 |     pub fn join(self) -> ThreadResult<()> {
[INFO] [stdout]     |            ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 2.38s
[INFO] running `Command { std: "docker" "inspect" "b60a23973519d2cf136739089a6420b33914d2f5a2210acc2594fcef5ab53767", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b60a23973519d2cf136739089a6420b33914d2f5a2210acc2594fcef5ab53767", kill_on_drop: false }`
[INFO] [stdout] b60a23973519d2cf136739089a6420b33914d2f5a2210acc2594fcef5ab53767
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+432e145bd5a974c5b6f4dd9b352891bd7502b69d" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 33386210fb548372926d0cc8efaff62e081c174885e00949a81dd48ec21b2241
[INFO] running `Command { std: "docker" "start" "-a" "33386210fb548372926d0cc8efaff62e081c174885e00949a81dd48ec21b2241", kill_on_drop: false }`
[INFO] [stderr] warning: variant is never constructed: `Aborted`
[INFO] [stderr]   --> src/solver.rs:30:5
[INFO] [stderr]    |
[INFO] [stderr] 30 |     Aborted(Matrix),
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `problem`
[INFO] [stderr]   --> src/solver.rs:35:5
[INFO] [stderr]    |
[INFO] [stderr] 35 |     problem: Problem<N, C>,
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `thread`
[INFO] [stderr]    --> src/solver.rs:119:5
[INFO] [stderr]     |
[INFO] [stderr] 119 |     thread: JoinHandle<()>,
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `try_recv`
[INFO] [stderr]    --> src/solver.rs:179:12
[INFO] [stderr]     |
[INFO] [stderr] 179 |     pub fn try_recv(&self) -> Result<SolverThreadEvent, TryRecvError> {
[INFO] [stderr]     |            ^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `join`
[INFO] [stderr]    --> src/solver.rs:187:12
[INFO] [stderr]     |
[INFO] [stderr] 187 |     pub fn join(self) -> ThreadResult<()> {
[INFO] [stderr]     |            ^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: 5 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `super::*`
[INFO] [stderr]    --> src/dlx.rs:222:9
[INFO] [stderr]     |
[INFO] [stderr] 222 |     use super::*;
[INFO] [stderr]     |         ^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variant is never constructed: `Aborted`
[INFO] [stderr]   --> src/solver.rs:30:5
[INFO] [stderr]    |
[INFO] [stderr] 30 |     Aborted(Matrix),
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `problem`
[INFO] [stderr]   --> src/solver.rs:35:5
[INFO] [stderr]    |
[INFO] [stderr] 35 |     problem: Problem<N, C>,
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `thread`
[INFO] [stderr]    --> src/solver.rs:119:5
[INFO] [stderr]     |
[INFO] [stderr] 119 |     thread: JoinHandle<()>,
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `try_recv`
[INFO] [stderr]    --> src/solver.rs:179:12
[INFO] [stderr]     |
[INFO] [stderr] 179 |     pub fn try_recv(&self) -> Result<SolverThreadEvent, TryRecvError> {
[INFO] [stderr]     |            ^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `join`
[INFO] [stderr]    --> src/solver.rs:187:12
[INFO] [stderr]     |
[INFO] [stderr] 187 |     pub fn join(self) -> ThreadResult<()> {
[INFO] [stderr]     |            ^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: 6 warnings emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.01s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/exact_cover-7d3314e3d462011a)
[INFO] [stdout] 
[INFO] [stdout] running 3 tests
[INFO] [stdout] test dlx::tests::matrix_search_should_solve_exact_cover ... ok
[INFO] [stdout] test problem::tests::problem_can_be_created ... ok
[INFO] [stdout] test solver::tests::solver_can_solve_problem ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 3 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] [stderr]    Doc-tests exact-cover
[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" "33386210fb548372926d0cc8efaff62e081c174885e00949a81dd48ec21b2241", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "33386210fb548372926d0cc8efaff62e081c174885e00949a81dd48ec21b2241", kill_on_drop: false }`
[INFO] [stdout] 33386210fb548372926d0cc8efaff62e081c174885e00949a81dd48ec21b2241