[INFO] cloning repository https://github.com/godcodehunter/solve_halt_problem
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/godcodehunter/solve_halt_problem" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fgodcodehunter%2Fsolve_halt_problem", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fgodcodehunter%2Fsolve_halt_problem'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 0192a3c01f0df7c7fa3da1e1762ad38aa258b339
[INFO] checking godcodehunter/solve_halt_problem against master#18a029cfe8e761533634bda8fe8a14e30280a21b for pr-139646
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fgodcodehunter%2Fsolve_halt_problem" "/workspace/builds/worker-4-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/godcodehunter/solve_halt_problem on toolchain 18a029cfe8e761533634bda8fe8a14e30280a21b
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+18a029cfe8e761533634bda8fe8a14e30280a21b" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/godcodehunter/solve_halt_problem
[INFO] finished tweaking git repo https://github.com/godcodehunter/solve_halt_problem
[INFO] tweaked toml for git repo https://github.com/godcodehunter/solve_halt_problem written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/godcodehunter/solve_halt_problem 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" "+18a029cfe8e761533634bda8fe8a14e30280a21b" "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-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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:b0b074c097205a61b89e8ad263052f976b2b332c4dc5f02aef1fe52501660d6e" "/opt/rustwide/cargo-home/bin/cargo" "+18a029cfe8e761533634bda8fe8a14e30280a21b" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 852bb6ee187677037d91f90156bcd51ff59e0dfe977cdd2a830bdbc60d82e212
[INFO] running `Command { std: "docker" "start" "-a" "852bb6ee187677037d91f90156bcd51ff59e0dfe977cdd2a830bdbc60d82e212", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "852bb6ee187677037d91f90156bcd51ff59e0dfe977cdd2a830bdbc60d82e212", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "852bb6ee187677037d91f90156bcd51ff59e0dfe977cdd2a830bdbc60d82e212", kill_on_drop: false }`
[INFO] [stdout] 852bb6ee187677037d91f90156bcd51ff59e0dfe977cdd2a830bdbc60d82e212
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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:b0b074c097205a61b89e8ad263052f976b2b332c4dc5f02aef1fe52501660d6e" "/opt/rustwide/cargo-home/bin/cargo" "+18a029cfe8e761533634bda8fe8a14e30280a21b" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 66d5f9fb6884acb6855d3e4280eb12de72927ec063cc66c9eeca2a9bfa79dfa4
[INFO] running `Command { std: "docker" "start" "-a" "66d5f9fb6884acb6855d3e4280eb12de72927ec063cc66c9eeca2a9bfa79dfa4", kill_on_drop: false }`
[INFO] [stderr]     Checking solve_halt_problem v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `iter::Map`
[INFO] [stdout]  --> src/main.rs:1:44
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::{collections::{HashMap, HashSet}, iter::Map};
[INFO] [stdout]   |                                            ^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `iter::Map`
[INFO] [stdout]  --> src/main.rs:1:44
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::{collections::{HashMap, HashSet}, iter::Map};
[INFO] [stdout]   |                                            ^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `start_of_loop` is never read
[INFO] [stdout]    --> src/main.rs:145:13
[INFO] [stdout]     |
[INFO] [stdout] 145 |     let mut start_of_loop: Option<usize> = None;
[INFO] [stdout]     |             ^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout]     = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable `halt_candidate` is assigned to, but never used
[INFO] [stdout]    --> src/main.rs:146:13
[INFO] [stdout]     |
[INFO] [stdout] 146 |     let mut halt_candidate: Option<usize> = None;
[INFO] [stdout]     |             ^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: consider using `_halt_candidate` instead
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `start_of_loop` is never read
[INFO] [stdout]    --> src/main.rs:145:13
[INFO] [stdout]     |
[INFO] [stdout] 145 |     let mut start_of_loop: Option<usize> = None;
[INFO] [stdout]     |             ^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout]     = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `prev` is never read
[INFO] [stdout]    --> src/main.rs:148:13
[INFO] [stdout]     |
[INFO] [stdout] 148 |     let mut prev: usize = 0;
[INFO] [stdout]     |             ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable `halt_candidate` is assigned to, but never used
[INFO] [stdout]    --> src/main.rs:146:13
[INFO] [stdout]     |
[INFO] [stdout] 146 |     let mut halt_candidate: Option<usize> = None;
[INFO] [stdout]     |             ^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: consider using `_halt_candidate` instead
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `next` is never read
[INFO] [stdout]    --> src/main.rs:149:13
[INFO] [stdout]     |
[INFO] [stdout] 149 |     let mut next: usize = 0;
[INFO] [stdout]     |             ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `prev` is never read
[INFO] [stdout]    --> src/main.rs:148:13
[INFO] [stdout]     |
[INFO] [stdout] 148 |     let mut prev: usize = 0;
[INFO] [stdout]     |             ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `halt_candidate` is never read
[INFO] [stdout]    --> src/main.rs:173:13
[INFO] [stdout]     |
[INFO] [stdout] 173 |             halt_candidate = Some(prev);
[INFO] [stdout]     |             ^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `next` is never read
[INFO] [stdout]    --> src/main.rs:149:13
[INFO] [stdout]     |
[INFO] [stdout] 149 |     let mut next: usize = 0;
[INFO] [stdout]     |             ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `halt_candidate` is never read
[INFO] [stdout]    --> src/main.rs:173:13
[INFO] [stdout]     |
[INFO] [stdout] 173 |             halt_candidate = Some(prev);
[INFO] [stdout]     |             ^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.10s
[INFO] running `Command { std: "docker" "inspect" "66d5f9fb6884acb6855d3e4280eb12de72927ec063cc66c9eeca2a9bfa79dfa4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "66d5f9fb6884acb6855d3e4280eb12de72927ec063cc66c9eeca2a9bfa79dfa4", kill_on_drop: false }`
[INFO] [stdout] 66d5f9fb6884acb6855d3e4280eb12de72927ec063cc66c9eeca2a9bfa79dfa4