[INFO] cloning repository https://github.com/aldidana/ranjau
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/aldidana/ranjau" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Faldidana%2Franjau", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Faldidana%2Franjau'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 0fa9b11cb2e9a1a3f980252cdc50b26b419cd4ee
[INFO] checking aldidana/ranjau against master#bca37a20bd376ce3fd138e7cdee7fe704e0f8814 for pr-139493-3
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Faldidana%2Franjau" "/workspace/builds/worker-1-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1-tc1/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/aldidana/ranjau
[INFO] finished tweaking git repo https://github.com/aldidana/ranjau
[INFO] tweaked toml for git repo https://github.com/aldidana/ranjau written to /workspace/builds/worker-1-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/aldidana/ranjau on toolchain bca37a20bd376ce3fd138e7cdee7fe704e0f8814
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+bca37a20bd376ce3fd138e7cdee7fe704e0f8814" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/aldidana/ranjau 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" "+bca37a20bd376ce3fd138e7cdee7fe704e0f8814" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded rand_core v0.5.0
[INFO] [stderr]   Downloaded getrandom v0.1.8
[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:aa71247004a7fa38d13ec170f48f06cdedf5bc50b2a8645e56ed7e992e6fa513" "/opt/rustwide/cargo-home/bin/cargo" "+bca37a20bd376ce3fd138e7cdee7fe704e0f8814" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 601d592dbd65ac08f95bb052d328efeb0b5adcbdea6de3d265800f2809bbf23c
[INFO] running `Command { std: "docker" "start" "-a" "601d592dbd65ac08f95bb052d328efeb0b5adcbdea6de3d265800f2809bbf23c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "601d592dbd65ac08f95bb052d328efeb0b5adcbdea6de3d265800f2809bbf23c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "601d592dbd65ac08f95bb052d328efeb0b5adcbdea6de3d265800f2809bbf23c", kill_on_drop: false }`
[INFO] [stdout] 601d592dbd65ac08f95bb052d328efeb0b5adcbdea6de3d265800f2809bbf23c
[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:aa71247004a7fa38d13ec170f48f06cdedf5bc50b2a8645e56ed7e992e6fa513" "/opt/rustwide/cargo-home/bin/cargo" "+bca37a20bd376ce3fd138e7cdee7fe704e0f8814" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 33a81cee2adb8fa39bd5c98b57051b1caada7baac893f93115a87a5cb3f1dcd5
[INFO] running `Command { std: "docker" "start" "-a" "33a81cee2adb8fa39bd5c98b57051b1caada7baac893f93115a87a5cb3f1dcd5", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.60
[INFO] [stderr]     Checking c2-chacha v0.2.2
[INFO] [stderr]     Checking getrandom v0.1.8
[INFO] [stderr]     Checking rand_core v0.5.0
[INFO] [stderr]     Checking rand_chacha v0.2.1
[INFO] [stderr]     Checking rand v0.7.0
[INFO] [stderr]     Checking ranjau v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/mine.rs:44:17
[INFO] [stdout]    |
[INFO] [stdout] 44 |                 &self.mines.push(mine);
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 44 |                 let _ = &self.mines.push(mine);
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/mine.rs:55:9
[INFO] [stdout]    |
[INFO] [stdout] 55 |         &self.generate_empty_fields();
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 55 |         let _ = &self.generate_empty_fields();
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/mine.rs:63:9
[INFO] [stdout]    |
[INFO] [stdout] 63 |         &self.mines.reverse();
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 63 |         let _ = &self.mines.reverse();
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/mine.rs:44:17
[INFO] [stdout]    |
[INFO] [stdout] 44 |                 &self.mines.push(mine);
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 44 |                 let _ = &self.mines.push(mine);
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/mine.rs:55:9
[INFO] [stdout]    |
[INFO] [stdout] 55 |         &self.generate_empty_fields();
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 55 |         let _ = &self.generate_empty_fields();
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/mine.rs:63:9
[INFO] [stdout]    |
[INFO] [stdout] 63 |         &self.mines.reverse();
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 63 |         let _ = &self.mines.reverse();
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 2.36s
[INFO] running `Command { std: "docker" "inspect" "33a81cee2adb8fa39bd5c98b57051b1caada7baac893f93115a87a5cb3f1dcd5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "33a81cee2adb8fa39bd5c98b57051b1caada7baac893f93115a87a5cb3f1dcd5", kill_on_drop: false }`
[INFO] [stdout] 33a81cee2adb8fa39bd5c98b57051b1caada7baac893f93115a87a5cb3f1dcd5