[INFO] cloning repository https://github.com/Lakret/backtrack_rs
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Lakret/backtrack_rs" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FLakret%2Fbacktrack_rs", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FLakret%2Fbacktrack_rs'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 21a7dfdaf0c1a79561b1e3182f90e30563868603
[INFO] checking Lakret/backtrack_rs/21a7dfdaf0c1a79561b1e3182f90e30563868603 against master#ab869e094a907cc5d19b4080f22eccaf347f1f95 for pr-129604
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FLakret%2Fbacktrack_rs" "/workspace/builds/worker-5-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-5-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Lakret/backtrack_rs on toolchain ab869e094a907cc5d19b4080f22eccaf347f1f95
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/Lakret/backtrack_rs
[INFO] finished tweaking git repo https://github.com/Lakret/backtrack_rs
[INFO] tweaked toml for git repo https://github.com/Lakret/backtrack_rs written to /workspace/builds/worker-5-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/Lakret/backtrack_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" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded tinytemplate v1.0.4
[INFO] [stderr]   Downloaded quote v1.0.5
[INFO] [stderr]   Downloaded wasm-bindgen-shared v0.2.62
[INFO] [stderr]   Downloaded criterion-plot v0.4.2
[INFO] [stderr]   Downloaded wasm-bindgen-macro-support v0.2.62
[INFO] [stderr]   Downloaded wasm-bindgen-macro v0.2.62
[INFO] [stderr]   Downloaded wasm-bindgen-backend v0.2.62
[INFO] [stderr]   Downloaded serde_derive v1.0.110
[INFO] [stderr]   Downloaded js-sys v0.3.39
[INFO] [stderr]   Downloaded serde v1.0.110
[INFO] [stderr]   Downloaded ryu v1.0.4
[INFO] [stderr]   Downloaded bumpalo v3.3.0
[INFO] [stderr]   Downloaded criterion v0.3.2
[INFO] [stderr]   Downloaded oorandom v11.1.1
[INFO] [stderr]   Downloaded wasm-bindgen v0.2.62
[INFO] [stderr]   Downloaded syn v1.0.21
[INFO] [stderr]   Downloaded web-sys v0.3.39
[INFO] [stderr]   Downloaded plotters v0.2.14
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] f889935c998f2f95db1e7f71170daa669329b62b1a386f74840f672ead3f0476
[INFO] running `Command { std: "docker" "start" "-a" "f889935c998f2f95db1e7f71170daa669329b62b1a386f74840f672ead3f0476", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f889935c998f2f95db1e7f71170daa669329b62b1a386f74840f672ead3f0476", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f889935c998f2f95db1e7f71170daa669329b62b1a386f74840f672ead3f0476", kill_on_drop: false }`
[INFO] [stdout] f889935c998f2f95db1e7f71170daa669329b62b1a386f74840f672ead3f0476
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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=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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a1a113052d1ef4ea72b01a39f2b995f07131577dbc3cfc4a5d41939b159997fb
[INFO] running `Command { std: "docker" "start" "-a" "a1a113052d1ef4ea72b01a39f2b995f07131577dbc3cfc4a5d41939b159997fb", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v1.0.0
[INFO] [stderr]     Checking cfg-if v0.1.10
[INFO] [stderr]    Compiling maybe-uninit v2.0.0
[INFO] [stderr]    Compiling libc v0.2.70
[INFO] [stderr]    Compiling semver-parser v0.7.0
[INFO] [stderr]    Compiling serde v1.0.110
[INFO] [stderr]    Compiling byteorder v1.3.4
[INFO] [stderr]    Compiling memchr v2.3.3
[INFO] [stderr]    Compiling ryu v1.0.4
[INFO] [stderr]    Compiling proc-macro2 v1.0.12
[INFO] [stderr]    Compiling unicode-xid v0.2.0
[INFO] [stderr]    Compiling rayon-core v1.7.0
[INFO] [stderr]    Compiling syn v1.0.21
[INFO] [stderr]     Checking either v1.5.3
[INFO] [stderr]     Checking itoa v0.4.5
[INFO] [stderr]    Compiling bitflags v1.2.1
[INFO] [stderr]     Checking unicode-width v0.1.7
[INFO] [stderr]     Checking regex-syntax v0.6.17
[INFO] [stderr]     Checking textwrap v0.11.0
[INFO] [stderr]     Checking walkdir v2.3.1
[INFO] [stderr]     Checking itertools v0.9.0
[INFO] [stderr]     Checking oorandom v11.1.1
[INFO] [stderr]    Compiling semver v0.9.0
[INFO] [stderr]    Compiling crossbeam-utils v0.7.2
[INFO] [stderr]    Compiling memoffset v0.5.4
[INFO] [stderr]    Compiling crossbeam-epoch v0.8.2
[INFO] [stderr]    Compiling num-traits v0.2.11
[INFO] [stderr]     Checking clap v2.33.1
[INFO] [stderr]    Compiling rustc_version v0.2.3
[INFO] [stderr]     Checking csv-core v0.1.10
[INFO] [stderr]     Checking regex-automata v0.1.9
[INFO] [stderr]    Compiling cast v0.2.3
[INFO] [stderr]    Compiling quote v1.0.5
[INFO] [stderr]     Checking num_cpus v1.13.0
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking criterion-plot v0.4.2
[INFO] [stderr]     Checking crossbeam-queue v0.2.1
[INFO] [stderr]     Checking crossbeam-channel v0.4.2
[INFO] [stderr]     Checking regex v1.3.7
[INFO] [stderr]     Checking plotters v0.2.14
[INFO] [stderr]     Checking crossbeam-deque v0.7.3
[INFO] [stderr]     Checking crossbeam v0.7.3
[INFO] [stderr]     Checking backtrack_rs v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::thread::JoinHandle`
[INFO] [stdout]    --> src/lib.rs:210:5
[INFO] [stdout]     |
[INFO] [stdout] 210 | use std::thread::JoinHandle;
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `reduced_domain`
[INFO] [stdout]   --> src/ac3.rs:19:13
[INFO] [stdout]    |
[INFO] [stdout] 19 |         let reduced_domain = csp
[INFO] [stdout]    |             ^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_reduced_domain`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/ac3.rs:33:8
[INFO] [stdout]    |
[INFO] [stdout] 33 |       [x, y] => {}
[INFO] [stdout]    |        ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]   --> src/ac3.rs:33:11
[INFO] [stdout]    |
[INFO] [stdout] 33 |       [x, y] => {}
[INFO] [stdout]    |           ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/ac3.rs:15:7
[INFO] [stdout]    |
[INFO] [stdout] 15 |   let mut constraint_refs = csp.constraints.iter().collect::<Vec<_>>();
[INFO] [stdout]    |       ----^^^^^^^^^^^^^^^
[INFO] [stdout]    |       |
[INFO] [stdout]    |       help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `iteration`
[INFO] [stdout]    --> src/lib.rs:284:3
[INFO] [stdout]     |
[INFO] [stdout] 284 |   iteration: u32,
[INFO] [stdout]     |   ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_iteration`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `lazy_static::lazy_static`
[INFO] [stdout]  --> src/main.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | use lazy_static::lazy_static;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking rayon v1.3.0
[INFO] [stderr]     Checking bstr v0.2.13
[INFO] [stderr]     Checking serde_json v1.0.53
[INFO] [stderr]     Checking csv v1.1.3
[INFO] [stderr]     Checking tinytemplate v1.0.4
[INFO] [stderr]    Compiling serde_derive v1.0.110
[INFO] [stderr]     Checking criterion v0.3.2
[INFO] [stdout] warning: unused import: `black_box`
[INFO] [stdout]  --> benches/backtracking_bench.rs:1:17
[INFO] [stdout]   |
[INFO] [stdout] 1 | use criterion::{black_box, criterion_group, criterion_main, BenchmarkId, Criterion};
[INFO] [stdout]   |                 ^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::thread::JoinHandle`
[INFO] [stdout]    --> src/lib.rs:210:5
[INFO] [stdout]     |
[INFO] [stdout] 210 | use std::thread::JoinHandle;
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `lazy_static::lazy_static`
[INFO] [stdout]  --> src/main.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | use lazy_static::lazy_static;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `reduced_domain`
[INFO] [stdout]   --> src/ac3.rs:19:13
[INFO] [stdout]    |
[INFO] [stdout] 19 |         let reduced_domain = csp
[INFO] [stdout]    |             ^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_reduced_domain`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/ac3.rs:33:8
[INFO] [stdout]    |
[INFO] [stdout] 33 |       [x, y] => {}
[INFO] [stdout]    |        ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]   --> src/ac3.rs:33:11
[INFO] [stdout]    |
[INFO] [stdout] 33 |       [x, y] => {}
[INFO] [stdout]    |           ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/ac3.rs:15:7
[INFO] [stdout]    |
[INFO] [stdout] 15 |   let mut constraint_refs = csp.constraints.iter().collect::<Vec<_>>();
[INFO] [stdout]    |       ----^^^^^^^^^^^^^^^
[INFO] [stdout]    |       |
[INFO] [stdout]    |       help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `iteration`
[INFO] [stdout]    --> src/lib.rs:284:3
[INFO] [stdout]     |
[INFO] [stdout] 284 |   iteration: u32,
[INFO] [stdout]     |   ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_iteration`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 11.44s
[INFO] [stderr] warning: the following packages contain code that will be rejected by a future version of Rust: criterion v0.3.2
[INFO] [stderr] note: to see what the problems were, use the option `--future-incompat-report`, or run `cargo report future-incompatibilities --id 1`
[INFO] running `Command { std: "docker" "inspect" "a1a113052d1ef4ea72b01a39f2b995f07131577dbc3cfc4a5d41939b159997fb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a1a113052d1ef4ea72b01a39f2b995f07131577dbc3cfc4a5d41939b159997fb", kill_on_drop: false }`
[INFO] [stdout] a1a113052d1ef4ea72b01a39f2b995f07131577dbc3cfc4a5d41939b159997fb