[INFO] cloning repository https://github.com/connesc/sudoku-rs
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/connesc/sudoku-rs" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fconnesc%2Fsudoku-rs", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fconnesc%2Fsudoku-rs'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 0088c8377ff84527a1d49db816f17b883deb5df5
[INFO] testing connesc/sudoku-rs against try#0936b3db0ae648ba2d5b60eb08cf4faf2ddab0c6 for pr-137122-2
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fconnesc%2Fsudoku-rs" "/workspace/builds/worker-2-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/connesc/sudoku-rs
[INFO] finished tweaking git repo https://github.com/connesc/sudoku-rs
[INFO] tweaked toml for git repo https://github.com/connesc/sudoku-rs written to /workspace/builds/worker-2-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/connesc/sudoku-rs on toolchain 0936b3db0ae648ba2d5b60eb08cf4faf2ddab0c6
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+0936b3db0ae648ba2d5b60eb08cf4faf2ddab0c6" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/connesc/sudoku-rs already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+0936b3db0ae648ba2d5b60eb08cf4faf2ddab0c6" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/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@sha256:90999bfc7ae267e83380e433d8e61a7c072ca6729e92edbae886d3423b3a6f4c" "/opt/rustwide/cargo-home/bin/cargo" "+0936b3db0ae648ba2d5b60eb08cf4faf2ddab0c6" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] f1721539ebd662522ccb64e19fcfc1b0e76301cb7f06c3d323f2bfbfc472577e
[INFO] running `Command { std: "docker" "start" "-a" "f1721539ebd662522ccb64e19fcfc1b0e76301cb7f06c3d323f2bfbfc472577e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f1721539ebd662522ccb64e19fcfc1b0e76301cb7f06c3d323f2bfbfc472577e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f1721539ebd662522ccb64e19fcfc1b0e76301cb7f06c3d323f2bfbfc472577e", kill_on_drop: false }`
[INFO] [stdout] f1721539ebd662522ccb64e19fcfc1b0e76301cb7f06c3d323f2bfbfc472577e
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/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" "RUSTDOCFLAGS=--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@sha256:90999bfc7ae267e83380e433d8e61a7c072ca6729e92edbae886d3423b3a6f4c" "/opt/rustwide/cargo-home/bin/cargo" "+0936b3db0ae648ba2d5b60eb08cf4faf2ddab0c6" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 5054af9d6cfee53bdf38d209f757eca67004842d77fc2912784bcf97d35db141
[INFO] running `Command { std: "docker" "start" "-a" "5054af9d6cfee53bdf38d209f757eca67004842d77fc2912784bcf97d35db141", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.84
[INFO] [stderr]    Compiling getrandom v0.2.2
[INFO] [stderr]    Compiling ppv-lite86 v0.2.10
[INFO] [stderr]    Compiling rand_core v0.6.1
[INFO] [stderr]    Compiling rand_chacha v0.3.0
[INFO] [stderr]    Compiling rand v0.8.3
[INFO] [stderr]    Compiling sudoku v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]    --> src/lib.rs:335:5
[INFO] [stdout]     |
[INFO] [stdout] 335 |     &mut items[..len].shuffle(rng);
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 335 |     let _ = &mut items[..len].shuffle(rng);
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: lifetime flowing from input to output with different syntax can be confusing
[INFO] [stdout]    --> src/lib.rs:445:18
[INFO] [stdout]     |
[INFO] [stdout] 445 |     fn new(grid: &mut Grid) -> Solver {
[INFO] [stdout]     |                  ^^^^^^^^^     ------ the lifetime gets resolved as `'_`
[INFO] [stdout]     |                  |
[INFO] [stdout]     |                  this lifetime flows to the output
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stdout] help: one option is to remove the lifetime for references and use the anonymous lifetime for paths
[INFO] [stdout]     |
[INFO] [stdout] 445 |     fn new(grid: &mut Grid) -> Solver<'_> {
[INFO] [stdout]     |                                      ++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 4.61s
[INFO] running `Command { std: "docker" "inspect" "5054af9d6cfee53bdf38d209f757eca67004842d77fc2912784bcf97d35db141", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5054af9d6cfee53bdf38d209f757eca67004842d77fc2912784bcf97d35db141", kill_on_drop: false }`
[INFO] [stdout] 5054af9d6cfee53bdf38d209f757eca67004842d77fc2912784bcf97d35db141
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/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" "RUSTDOCFLAGS=--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@sha256:90999bfc7ae267e83380e433d8e61a7c072ca6729e92edbae886d3423b3a6f4c" "/opt/rustwide/cargo-home/bin/cargo" "+0936b3db0ae648ba2d5b60eb08cf4faf2ddab0c6" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a188e7c9930b6ff55645993134dd398b7b6212a2f39db638cc3e3a385696a8ee
[INFO] running `Command { std: "docker" "start" "-a" "a188e7c9930b6ff55645993134dd398b7b6212a2f39db638cc3e3a385696a8ee", kill_on_drop: false }`
[INFO] [stderr]    Compiling sudoku v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]    --> src/lib.rs:335:5
[INFO] [stdout]     |
[INFO] [stdout] 335 |     &mut items[..len].shuffle(rng);
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 335 |     let _ = &mut items[..len].shuffle(rng);
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: lifetime flowing from input to output with different syntax can be confusing
[INFO] [stdout]    --> src/lib.rs:445:18
[INFO] [stdout]     |
[INFO] [stdout] 445 |     fn new(grid: &mut Grid) -> Solver {
[INFO] [stdout]     |                  ^^^^^^^^^     ------ the lifetime gets resolved as `'_`
[INFO] [stdout]     |                  |
[INFO] [stdout]     |                  this lifetime flows to the output
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stdout] help: one option is to remove the lifetime for references and use the anonymous lifetime for paths
[INFO] [stdout]     |
[INFO] [stdout] 445 |     fn new(grid: &mut Grid) -> Solver<'_> {
[INFO] [stdout]     |                                      ++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]    --> src/lib.rs:335:5
[INFO] [stdout]     |
[INFO] [stdout] 335 |     &mut items[..len].shuffle(rng);
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 335 |     let _ = &mut items[..len].shuffle(rng);
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: lifetime flowing from input to output with different syntax can be confusing
[INFO] [stdout]    --> src/lib.rs:445:18
[INFO] [stdout]     |
[INFO] [stdout] 445 |     fn new(grid: &mut Grid) -> Solver {
[INFO] [stdout]     |                  ^^^^^^^^^     ------ the lifetime gets resolved as `'_`
[INFO] [stdout]     |                  |
[INFO] [stdout]     |                  this lifetime flows to the output
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stdout] help: one option is to remove the lifetime for references and use the anonymous lifetime for paths
[INFO] [stdout]     |
[INFO] [stdout] 445 |     fn new(grid: &mut Grid) -> Solver<'_> {
[INFO] [stdout]     |                                      ++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.86s
[INFO] running `Command { std: "docker" "inspect" "a188e7c9930b6ff55645993134dd398b7b6212a2f39db638cc3e3a385696a8ee", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a188e7c9930b6ff55645993134dd398b7b6212a2f39db638cc3e3a385696a8ee", kill_on_drop: false }`
[INFO] [stdout] a188e7c9930b6ff55645993134dd398b7b6212a2f39db638cc3e3a385696a8ee
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/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" "RUSTDOCFLAGS=--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@sha256:90999bfc7ae267e83380e433d8e61a7c072ca6729e92edbae886d3423b3a6f4c" "/opt/rustwide/cargo-home/bin/cargo" "+0936b3db0ae648ba2d5b60eb08cf4faf2ddab0c6" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 6203b8a19fc5041ea402c45930737548dff6a66b17d6ea56bf675a1b76079bc6
[INFO] running `Command { std: "docker" "start" "-a" "6203b8a19fc5041ea402c45930737548dff6a66b17d6ea56bf675a1b76079bc6", kill_on_drop: false }`
[INFO] [stderr] warning: unused borrow that must be used
[INFO] [stderr]    --> src/lib.rs:335:5
[INFO] [stderr]     |
[INFO] [stderr] 335 |     &mut items[..len].shuffle(rng);
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr] help: use `let _ = ...` to ignore the resulting value
[INFO] [stderr]     |
[INFO] [stderr] 335 |     let _ = &mut items[..len].shuffle(rng);
[INFO] [stderr]     |     +++++++
[INFO] [stderr] 
[INFO] [stderr] warning: lifetime flowing from input to output with different syntax can be confusing
[INFO] [stderr]    --> src/lib.rs:445:18
[INFO] [stderr]     |
[INFO] [stderr] 445 |     fn new(grid: &mut Grid) -> Solver {
[INFO] [stderr]     |                  ^^^^^^^^^     ------ the lifetime gets resolved as `'_`
[INFO] [stderr]     |                  |
[INFO] [stderr]     |                  this lifetime flows to the output
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stderr] help: one option is to remove the lifetime for references and use the anonymous lifetime for paths
[INFO] [stderr]     |
[INFO] [stderr] 445 |     fn new(grid: &mut Grid) -> Solver<'_> {
[INFO] [stderr]     |                                      ++++
[INFO] [stderr] 
[INFO] [stderr] warning: `sudoku` (lib) generated 2 warnings
[INFO] [stderr] warning: `sudoku` (lib test) generated 2 warnings (2 duplicates)
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.04s
[INFO] [stderr]      Running unittests src/lib.rs (/opt/rustwide/target/debug/deps/sudoku-5ed99b935ca95e13)
[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]      Running unittests src/main.rs (/opt/rustwide/target/debug/deps/sudoku-5dfc585df7067d74)
[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 sudoku
[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" "6203b8a19fc5041ea402c45930737548dff6a66b17d6ea56bf675a1b76079bc6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6203b8a19fc5041ea402c45930737548dff6a66b17d6ea56bf675a1b76079bc6", kill_on_drop: false }`
[INFO] [stdout] 6203b8a19fc5041ea402c45930737548dff6a66b17d6ea56bf675a1b76079bc6