[INFO] cloning repository https://github.com/hallettj/sat-solver-exercise
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/hallettj/sat-solver-exercise" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fhallettj%2Fsat-solver-exercise", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fhallettj%2Fsat-solver-exercise'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 79e8b29506f5a0352c3d422d86ccd13fae13948a
[INFO] checking hallettj/sat-solver-exercise against master#385fa9d845dd326c6bbfd58c22244215e431948a for never-type-fallback-to-never
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fhallettj%2Fsat-solver-exercise" "/workspace/builds/worker-1-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/hallettj/sat-solver-exercise on toolchain 385fa9d845dd326c6bbfd58c22244215e431948a
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/hallettj/sat-solver-exercise
[INFO] finished tweaking git repo https://github.com/hallettj/sat-solver-exercise
[INFO] tweaked toml for git repo https://github.com/hallettj/sat-solver-exercise written to /workspace/builds/worker-1-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/hallettj/sat-solver-exercise 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" "+385fa9d845dd326c6bbfd58c22244215e431948a" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded vec_mut_scan v0.1.0
[INFO] [stderr]   Downloaded varisat-dimacs v0.2.1
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[INFO] [stderr]   Downloaded partial_ref_derive v0.3.1
[INFO] [stderr]   Downloaded partial_ref v0.3.1
[INFO] [stderr]   Downloaded varisat-checker v0.2.1
[INFO] [stderr]   Downloaded quote v1.0.4
[INFO] [stderr]   Downloaded varisat v0.2.1
[INFO] [stderr]   Downloaded backtrace-sys v0.1.37
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 91934f594a73a0e6a0b2256e7bca543a8c78c29cebcc1754e48cd59d9d6d7971
[INFO] running `Command { std: "docker" "start" "-a" "91934f594a73a0e6a0b2256e7bca543a8c78c29cebcc1754e48cd59d9d6d7971", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "91934f594a73a0e6a0b2256e7bca543a8c78c29cebcc1754e48cd59d9d6d7971", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "91934f594a73a0e6a0b2256e7bca543a8c78c29cebcc1754e48cd59d9d6d7971", kill_on_drop: false }`
[INFO] [stdout] 91934f594a73a0e6a0b2256e7bca543a8c78c29cebcc1754e48cd59d9d6d7971
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a49c2f7e5a959664424813b785cbbfd73bf7d751f0b745bc851aeb61ea577939
[INFO] running `Command { std: "docker" "start" "-a" "a49c2f7e5a959664424813b785cbbfd73bf7d751f0b745bc851aeb61ea577939", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.12
[INFO] [stderr]    Compiling libc v0.2.69
[INFO] [stderr]    Compiling unicode-xid v0.2.0
[INFO] [stderr]    Compiling syn v1.0.18
[INFO] [stderr]    Compiling cc v1.0.52
[INFO] [stderr]    Compiling failure_derive v0.1.8
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]    Compiling memchr v2.3.3
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[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]     Checking cfg-if v0.1.10
[INFO] [stderr]     Checking rustc-demangle v0.1.16
[INFO] [stderr]    Compiling maybe-uninit v2.0.0
[INFO] [stderr]     Checking varisat-formula v0.2.1
[INFO] [stderr]    Compiling lazy_static v1.4.0
[INFO] [stderr]    Compiling log v0.4.8
[INFO] [stderr]    Compiling thread_local v1.0.1
[INFO] [stderr]     Checking itoa v0.4.5
[INFO] [stderr]    Compiling regex-syntax v0.6.17
[INFO] [stderr]    Compiling num-traits v0.2.11
[INFO] [stderr]    Compiling serde v1.0.106
[INFO] [stderr]    Compiling num-integer v0.1.42
[INFO] [stderr]     Checking hashbrown v0.3.1
[INFO] [stderr]     Checking vec_mut_scan v0.1.0
[INFO] [stderr]    Compiling aho-corasick v0.7.10
[INFO] [stderr]     Checking smallvec v0.6.13
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[INFO] [stderr]    Compiling backtrace-sys v0.1.37
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[INFO] [stderr]    Compiling synstructure v0.12.3
[INFO] [stderr]    Compiling varisat-internal-macros v0.2.1
[INFO] [stderr]    Compiling serde_derive v1.0.106
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[INFO] [stderr]     Checking failure v0.1.8
[INFO] [stderr]     Checking varisat-dimacs v0.2.1
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[INFO] [stderr]     Checking varisat-checker v0.2.1
[INFO] [stderr]     Checking sudoku v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: the item `Puzzle` is imported redundantly
[INFO] [stdout]    --> src/solver.rs:128:9
[INFO] [stdout]     |
[INFO] [stdout] 127 |     use super::*;
[INFO] [stdout]     |         -------- the item `Puzzle` is already imported here
[INFO] [stdout] 128 |     use crate::puzzle::Puzzle;
[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]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 14.25s
[INFO] running `Command { std: "docker" "inspect" "a49c2f7e5a959664424813b785cbbfd73bf7d751f0b745bc851aeb61ea577939", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a49c2f7e5a959664424813b785cbbfd73bf7d751f0b745bc851aeb61ea577939", kill_on_drop: false }`
[INFO] [stdout] a49c2f7e5a959664424813b785cbbfd73bf7d751f0b745bc851aeb61ea577939