[INFO] updating cached repository https://github.com/csreid/nqueens-rs
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune"`
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 5d80a29371cad247c2e6d20a82b62f12dde864d3
[INFO] checking csreid/nqueens-rs against master#45d050cde277b22a755847338f2acc2c7b834141 for pr-71393
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fcsreid%2Fnqueens-rs" "/workspace/builds/worker-6/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/csreid/nqueens-rs on toolchain 45d050cde277b22a755847338f2acc2c7b834141
[INFO] running `"/workspace/cargo-home/bin/cargo" "+45d050cde277b22a755847338f2acc2c7b834141" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/csreid/nqueens-rs
[INFO] finished tweaking git repo https://github.com/csreid/nqueens-rs
[INFO] tweaked toml for git repo https://github.com/csreid/nqueens-rs written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] crate git repo https://github.com/csreid/nqueens-rs already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+45d050cde277b22a755847338f2acc2c7b834141" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+45d050cde277b22a755847338f2acc2c7b834141" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] d0222747d4c7ff21fdfd5b550c36be0d77fb3845c7908e908c92afd1b421e406
[INFO] running `"docker" "start" "-a" "d0222747d4c7ff21fdfd5b550c36be0d77fb3845c7908e908c92afd1b421e406"`
[INFO] [stderr]     Checking rand v0.4.3
[INFO] [stderr]     Checking num-complex v0.1.43
[INFO] [stderr]     Checking num-integer v0.1.39
[INFO] [stderr]     Checking num-iter v0.1.37
[INFO] [stderr]     Checking num-bigint v0.1.44
[INFO] [stderr]     Checking num-rational v0.1.42
[INFO] [stderr]     Checking num v0.1.42
[INFO] [stderr]     Checking stopwatch v0.0.7
[INFO] [stderr]     Checking nqueens-rs v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: unnecessary parentheses around `for` iterator expression
[INFO] [stderr]    --> src/main.rs:118:12
[INFO] [stderr]     |
[INFO] [stderr] 118 |         for i in (0..=N) {
[INFO] [stderr]     |                  ^^^^^^^ help: remove these parentheses
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_parens)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around `for` iterator expression
[INFO] [stderr]    --> src/main.rs:119:13
[INFO] [stderr]     |
[INFO] [stderr] 119 |             for j in (0..=N) {
[INFO] [stderr]     |                      ^^^^^^^ help: remove these parentheses
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around `for` iterator expression
[INFO] [stderr]    --> src/main.rs:182:12
[INFO] [stderr]     |
[INFO] [stderr] 182 |         for i in (0..N) {
[INFO] [stderr]     |                  ^^^^^^ help: remove these parentheses
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around `for` iterator expression
[INFO] [stderr]    --> src/main.rs:183:13
[INFO] [stderr]     |
[INFO] [stderr] 183 |             for j in (0..N) {
[INFO] [stderr]     |                      ^^^^^^ help: remove these parentheses
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around assigned value
[INFO] [stderr]    --> src/main.rs:245:13
[INFO] [stderr]     |
[INFO] [stderr] 245 |     let time = (sw.elapsed_ms() as f64);
[INFO] [stderr]     |                ^^^^^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around `for` iterator expression
[INFO] [stderr]    --> src/main.rs:118:12
[INFO] [stderr]     |
[INFO] [stderr] 118 |         for i in (0..=N) {
[INFO] [stderr]     |                  ^^^^^^^ help: remove these parentheses
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_parens)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around `for` iterator expression
[INFO] [stderr]    --> src/main.rs:119:13
[INFO] [stderr]     |
[INFO] [stderr] 119 |             for j in (0..=N) {
[INFO] [stderr]     |                      ^^^^^^^ help: remove these parentheses
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around `for` iterator expression
[INFO] [stderr]    --> src/main.rs:182:12
[INFO] [stderr]     |
[INFO] [stderr] 182 |         for i in (0..N) {
[INFO] [stderr]     |                  ^^^^^^ help: remove these parentheses
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around `for` iterator expression
[INFO] [stderr]    --> src/main.rs:183:13
[INFO] [stderr]     |
[INFO] [stderr] 183 |             for j in (0..N) {
[INFO] [stderr]     |                      ^^^^^^ help: remove these parentheses
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around assigned value
[INFO] [stderr]    --> src/main.rs:245:13
[INFO] [stderr]     |
[INFO] [stderr] 245 |     let time = (sw.elapsed_ms() as f64);
[INFO] [stderr]     |                ^^^^^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `i`
[INFO] [stderr]    --> src/main.rs:118:7
[INFO] [stderr]     |
[INFO] [stderr] 118 |         for i in (0..=N) {
[INFO] [stderr]     |             ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `children`
[INFO] [stderr]    --> src/main.rs:219:7
[INFO] [stderr]     |
[INFO] [stderr] 219 |         let children = self.children();
[INFO] [stderr]     |             ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_children`
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `n_queens_bestfs`
[INFO] [stderr]    --> src/main.rs:193:2
[INFO] [stderr]     |
[INFO] [stderr] 193 |     fn n_queens_bestfs(&self, n:i32) -> (Board, i32) {
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:78:4
[INFO] [stderr]    |
[INFO] [stderr] 78 |             write!(f, "+---");
[INFO] [stderr]    |             ^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr]    = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:81:3
[INFO] [stderr]    |
[INFO] [stderr] 81 |         write!(f, "+\n");
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr]    = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:86:6
[INFO] [stderr]    |
[INFO] [stderr] 86 |                     write!(f, "| Q ");
[INFO] [stderr]    |                     ^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr]    = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:88:6
[INFO] [stderr]    |
[INFO] [stderr] 88 |                     write!(f, "|   ");
[INFO] [stderr]    |                     ^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr]    = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:92:4
[INFO] [stderr]    |
[INFO] [stderr] 92 |             write!(f, "|\n");
[INFO] [stderr]    |             ^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr]    = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:95:5
[INFO] [stderr]    |
[INFO] [stderr] 95 |                 write!(f, "+---");
[INFO] [stderr]    |                 ^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr]    = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:97:4
[INFO] [stderr]    |
[INFO] [stderr] 97 |             write!(f, "+\n");
[INFO] [stderr]    |             ^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr]    = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: variable `startTime` should have a snake case name
[INFO] [stderr]    --> src/main.rs:220:7
[INFO] [stderr]     |
[INFO] [stderr] 220 |         let startTime = Stopwatch::start_new();
[INFO] [stderr]     |             ^^^^^^^^^ help: convert the identifier to snake case: `start_time`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(non_snake_case)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `i`
[INFO] [stderr]    --> src/main.rs:118:7
[INFO] [stderr]     |
[INFO] [stderr] 118 |         for i in (0..=N) {
[INFO] [stderr]     |             ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `children`
[INFO] [stderr]    --> src/main.rs:219:7
[INFO] [stderr]     |
[INFO] [stderr] 219 |         let children = self.children();
[INFO] [stderr]     |             ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_children`
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `n_queens_bestfs`
[INFO] [stderr]    --> src/main.rs:193:2
[INFO] [stderr]     |
[INFO] [stderr] 193 |     fn n_queens_bestfs(&self, n:i32) -> (Board, i32) {
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:78:4
[INFO] [stderr]    |
[INFO] [stderr] 78 |             write!(f, "+---");
[INFO] [stderr]    |             ^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr]    = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:81:3
[INFO] [stderr]    |
[INFO] [stderr] 81 |         write!(f, "+\n");
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr]    = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:86:6
[INFO] [stderr]    |
[INFO] [stderr] 86 |                     write!(f, "| Q ");
[INFO] [stderr]    |                     ^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr]    = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:88:6
[INFO] [stderr]    |
[INFO] [stderr] 88 |                     write!(f, "|   ");
[INFO] [stderr]    |                     ^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr]    = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:92:4
[INFO] [stderr]    |
[INFO] [stderr] 92 |             write!(f, "|\n");
[INFO] [stderr]    |             ^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr]    = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:95:5
[INFO] [stderr]    |
[INFO] [stderr] 95 |                 write!(f, "+---");
[INFO] [stderr]    |                 ^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr]    = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:97:4
[INFO] [stderr]    |
[INFO] [stderr] 97 |             write!(f, "+\n");
[INFO] [stderr]    |             ^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr]    = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: variable `startTime` should have a snake case name
[INFO] [stderr]    --> src/main.rs:220:7
[INFO] [stderr]     |
[INFO] [stderr] 220 |         let startTime = Stopwatch::start_new();
[INFO] [stderr]     |             ^^^^^^^^^ help: convert the identifier to snake case: `start_time`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(non_snake_case)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: 16 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] warning: 16 warnings emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 5.62s
[INFO] running `"docker" "inspect" "d0222747d4c7ff21fdfd5b550c36be0d77fb3845c7908e908c92afd1b421e406"`
[INFO] running `"docker" "rm" "-f" "d0222747d4c7ff21fdfd5b550c36be0d77fb3845c7908e908c92afd1b421e406"`
[INFO] [stdout] d0222747d4c7ff21fdfd5b550c36be0d77fb3845c7908e908c92afd1b421e406