[INFO] cloning repository https://github.com/kingdom5500/minesweeper
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/kingdom5500/minesweeper" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkingdom5500%2Fminesweeper", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkingdom5500%2Fminesweeper'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] be846ba82a00e536dfb8b99d306d390004f58399
[INFO] checking kingdom5500/minesweeper against master#385fa9d845dd326c6bbfd58c22244215e431948a for absurd-question-mark-desugar
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkingdom5500%2Fminesweeper" "/workspace/builds/worker-0-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/kingdom5500/minesweeper 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/kingdom5500/minesweeper
[INFO] finished tweaking git repo https://github.com/kingdom5500/minesweeper
[INFO] tweaked toml for git repo https://github.com/kingdom5500/minesweeper written to /workspace/builds/worker-0-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/kingdom5500/minesweeper 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]  Downloading crates ...
[INFO] [stderr]   Downloaded termion v1.5.5
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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] e7f8bb49096efca7ed47005e2936392efcadbc8d748410007978e28db44af274
[INFO] running `Command { std: "docker" "start" "-a" "e7f8bb49096efca7ed47005e2936392efcadbc8d748410007978e28db44af274", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e7f8bb49096efca7ed47005e2936392efcadbc8d748410007978e28db44af274", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e7f8bb49096efca7ed47005e2936392efcadbc8d748410007978e28db44af274", kill_on_drop: false }`
[INFO] [stdout] e7f8bb49096efca7ed47005e2936392efcadbc8d748410007978e28db44af274
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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] 559598d08afdce1e9509904397ab519805c4d039ea70864d752a2de4cfcd8e86
[INFO] running `Command { std: "docker" "start" "-a" "559598d08afdce1e9509904397ab519805c4d039ea70864d752a2de4cfcd8e86", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.66
[INFO] [stderr]    Compiling getrandom v0.1.14
[INFO] [stderr]     Checking ppv-lite86 v0.2.6
[INFO] [stderr]     Checking numtoa v0.1.0
[INFO] [stderr]     Checking c2-chacha v0.2.3
[INFO] [stderr]     Checking termion v1.5.5
[INFO] [stderr]     Checking rand_core v0.5.1
[INFO] [stderr]     Checking rand_chacha v0.2.1
[INFO] [stderr]     Checking rand v0.7.3
[INFO] [stderr]     Checking minesweeper v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/minefield.rs:263:13
[INFO] [stdout]     |
[INFO] [stdout] 263 |         let mut tile = self.get_tile_mut(row, column)?;
[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: variable does not need to be mutable
[INFO] [stdout]    --> src/minefield.rs:282:13
[INFO] [stdout]     |
[INFO] [stdout] 282 |         let mut tile = self.get_tile_mut(row, column)?;
[INFO] [stdout]     |             ----^^^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/minefield.rs:263:13
[INFO] [stdout]     |
[INFO] [stdout] 263 |         let mut tile = self.get_tile_mut(row, column)?;
[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: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/minefield.rs:282:13
[INFO] [stdout]     |
[INFO] [stdout] 282 |         let mut tile = self.get_tile_mut(row, column)?;
[INFO] [stdout]     |             ----^^^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 3.32s
[INFO] running `Command { std: "docker" "inspect" "559598d08afdce1e9509904397ab519805c4d039ea70864d752a2de4cfcd8e86", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "559598d08afdce1e9509904397ab519805c4d039ea70864d752a2de4cfcd8e86", kill_on_drop: false }`
[INFO] [stdout] 559598d08afdce1e9509904397ab519805c4d039ea70864d752a2de4cfcd8e86
[INFO] checking kingdom5500/minesweeper against try#645bb72776a6a56a1a8f52631a44bd082b2ba509 for absurd-question-mark-desugar
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkingdom5500%2Fminesweeper" "/workspace/builds/worker-0-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/kingdom5500/minesweeper on toolchain 645bb72776a6a56a1a8f52631a44bd082b2ba509
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/kingdom5500/minesweeper
[INFO] finished tweaking git repo https://github.com/kingdom5500/minesweeper
[INFO] tweaked toml for git repo https://github.com/kingdom5500/minesweeper written to /workspace/builds/worker-0-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/kingdom5500/minesweeper 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" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/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" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] d6ae587d36bd2acb5970ec5f77d09dd0e217e8be4e497407bf4391827d28cf3e
[INFO] running `Command { std: "docker" "start" "-a" "d6ae587d36bd2acb5970ec5f77d09dd0e217e8be4e497407bf4391827d28cf3e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d6ae587d36bd2acb5970ec5f77d09dd0e217e8be4e497407bf4391827d28cf3e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d6ae587d36bd2acb5970ec5f77d09dd0e217e8be4e497407bf4391827d28cf3e", kill_on_drop: false }`
[INFO] [stdout] d6ae587d36bd2acb5970ec5f77d09dd0e217e8be4e497407bf4391827d28cf3e
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/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" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 73f4ee2c266b2fdbeadfe584f8ebd496042cab2e7ae0f6777c5286fd289f774e
[INFO] running `Command { std: "docker" "start" "-a" "73f4ee2c266b2fdbeadfe584f8ebd496042cab2e7ae0f6777c5286fd289f774e", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.66
[INFO] [stderr]    Compiling getrandom v0.1.14
[INFO] [stderr]     Checking ppv-lite86 v0.2.6
[INFO] [stderr]     Checking numtoa v0.1.0
[INFO] [stderr]     Checking c2-chacha v0.2.3
[INFO] [stderr]     Checking termion v1.5.5
[INFO] [stderr]     Checking rand_core v0.5.1
[INFO] [stderr]     Checking rand_chacha v0.2.1
[INFO] [stderr]     Checking rand v0.7.3
[INFO] [stderr]     Checking minesweeper v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/minefield.rs:263:13
[INFO] [stdout]     |
[INFO] [stdout] 263 |         let mut tile = self.get_tile_mut(row, column)?;
[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: variable does not need to be mutable
[INFO] [stdout]    --> src/minefield.rs:282:13
[INFO] [stdout]     |
[INFO] [stdout] 282 |         let mut tile = self.get_tile_mut(row, column)?;
[INFO] [stdout]     |             ----^^^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/minefield.rs:263:13
[INFO] [stdout]     |
[INFO] [stdout] 263 |         let mut tile = self.get_tile_mut(row, column)?;
[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: variable does not need to be mutable
[INFO] [stdout]    --> src/minefield.rs:282:13
[INFO] [stdout]     |
[INFO] [stdout] 282 |         let mut tile = self.get_tile_mut(row, column)?;
[INFO] [stdout]     |             ----^^^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 3.96s
[INFO] running `Command { std: "docker" "inspect" "73f4ee2c266b2fdbeadfe584f8ebd496042cab2e7ae0f6777c5286fd289f774e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "73f4ee2c266b2fdbeadfe584f8ebd496042cab2e7ae0f6777c5286fd289f774e", kill_on_drop: false }`
[INFO] [stdout] 73f4ee2c266b2fdbeadfe584f8ebd496042cab2e7ae0f6777c5286fd289f774e