[INFO] updating cached repository https://github.com/pierrechevalier83/2048-rs
[INFO] running `Command { std: "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", kill_on_drop: false }`
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 8de61e8e0342d54b0ae44b937ecb3952c4d2a94c
[INFO] checking pierrechevalier83/2048-rs against master#e22b61bff0bdd08be7665607cb7be3748c8a35d2 for pr-74627
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fpierrechevalier83%2F2048-rs" "/workspace/builds/worker-12/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-12/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/pierrechevalier83/2048-rs on toolchain e22b61bff0bdd08be7665607cb7be3748c8a35d2
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+e22b61bff0bdd08be7665607cb7be3748c8a35d2" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/pierrechevalier83/2048-rs
[INFO] finished tweaking git repo https://github.com/pierrechevalier83/2048-rs
[INFO] tweaked toml for git repo https://github.com/pierrechevalier83/2048-rs written to /workspace/builds/worker-12/source/Cargo.toml
[INFO] crate git repo https://github.com/pierrechevalier83/2048-rs already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+e22b61bff0bdd08be7665607cb7be3748c8a35d2" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--network" "none" "rustops/crates-build-env@sha256:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+e22b61bff0bdd08be7665607cb7be3748c8a35d2" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] c23c18d30f188740f42b024be9990e5099453dd9ccbc8a6b104eb555e732683c
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "c23c18d30f188740f42b024be9990e5099453dd9ccbc8a6b104eb555e732683c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c23c18d30f188740f42b024be9990e5099453dd9ccbc8a6b104eb555e732683c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c23c18d30f188740f42b024be9990e5099453dd9ccbc8a6b104eb555e732683c", kill_on_drop: false }`
[INFO] [stdout] c23c18d30f188740f42b024be9990e5099453dd9ccbc8a6b104eb555e732683c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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@sha256:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+e22b61bff0bdd08be7665607cb7be3748c8a35d2" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 4c194fde345bbd5c7fa5cb79f65e3a4ff62b8e53b5edcd0b7f7f2e6010fcb071
[INFO] running `Command { std: "docker" "start" "-a" "4c194fde345bbd5c7fa5cb79f65e3a4ff62b8e53b5edcd0b7f7f2e6010fcb071", kill_on_drop: false }`
[INFO] [stderr]     Checking num-traits v0.1.37
[INFO] [stderr]     Checking termion v1.2.0
[INFO] [stderr]     Checking matrix_display v0.3.0
[INFO] [stderr]     Checking num-integer v0.1.33
[INFO] [stderr]     Checking num-complex v0.1.36
[INFO] [stderr]     Checking num-bigint v0.1.36
[INFO] [stderr]     Checking num-iter v0.1.33
[INFO] [stderr]     Checking num-rational v0.1.36
[INFO] [stderr]     Checking num v0.1.37
[INFO] [stderr]     Checking game-2048 v0.5.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `std::iter::Iterator::collect` that must be used
[INFO] [stdout]   --> src/game.rs:69:9
[INFO] [stdout]    |
[INFO] [stdout] 69 | /         self.data
[INFO] [stdout] 70 | |             .chunks_mut(4)
[INFO] [stdout] 71 | |             .map(|row| {
[INFO] [stdout] 72 | |                 let (new_row, new_score) = match dir {
[INFO] [stdout] ...  |
[INFO] [stdout] 87 | |             })
[INFO] [stdout] 88 | |             .collect::<Vec<_>>();
[INFO] [stdout]    | |_________________________________^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: if you really need to exhaust the iterator, consider `.for_each(drop)` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::iter::Iterator::collect` that must be used
[INFO] [stdout]   --> src/game.rs:69:9
[INFO] [stdout]    |
[INFO] [stdout] 69 | /         self.data
[INFO] [stdout] 70 | |             .chunks_mut(4)
[INFO] [stdout] 71 | |             .map(|row| {
[INFO] [stdout] 72 | |                 let (new_row, new_score) = match dir {
[INFO] [stdout] ...  |
[INFO] [stdout] 87 | |             })
[INFO] [stdout] 88 | |             .collect::<Vec<_>>();
[INFO] [stdout]    | |_________________________________^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: if you really need to exhaust the iterator, consider `.for_each(drop)` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 6.06s
[INFO] running `Command { std: "docker" "inspect" "4c194fde345bbd5c7fa5cb79f65e3a4ff62b8e53b5edcd0b7f7f2e6010fcb071", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4c194fde345bbd5c7fa5cb79f65e3a4ff62b8e53b5edcd0b7f7f2e6010fcb071", kill_on_drop: false }`
[INFO] [stdout] 4c194fde345bbd5c7fa5cb79f65e3a4ff62b8e53b5edcd0b7f7f2e6010fcb071