[INFO] cloning repository https://github.com/stevewhims/fretboard
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/stevewhims/fretboard" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fstevewhims%2Ffretboard", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fstevewhims%2Ffretboard'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] e08c71b7c4e7f9008db7646513b0dd671886ee40
[INFO] checking stevewhims/fretboard against master#f82664191d0e8764b7435b9d72eb0e366b8b1464 for pr-83354
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fstevewhims%2Ffretboard" "/workspace/builds/worker-8/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-8/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/stevewhims/fretboard on toolchain f82664191d0e8764b7435b9d72eb0e366b8b1464
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f82664191d0e8764b7435b9d72eb0e366b8b1464" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/stevewhims/fretboard
[INFO] finished tweaking git repo https://github.com/stevewhims/fretboard
[INFO] tweaked toml for git repo https://github.com/stevewhims/fretboard written to /workspace/builds/worker-8/source/Cargo.toml
[INFO] crate git repo https://github.com/stevewhims/fretboard already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f82664191d0e8764b7435b9d72eb0e366b8b1464" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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" "rustops/crates-build-env@sha256:4f92631de1aa59f8320307485d3b3c869a5c90ab1d76ce2cffab9807b8c9a1fb" "/opt/rustwide/cargo-home/bin/cargo" "+f82664191d0e8764b7435b9d72eb0e366b8b1464" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 5dbc6f516013aaecf856867e446adaeda9c647f79cdcf3e31cb9ffb9068780bd
[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" "5dbc6f516013aaecf856867e446adaeda9c647f79cdcf3e31cb9ffb9068780bd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5dbc6f516013aaecf856867e446adaeda9c647f79cdcf3e31cb9ffb9068780bd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5dbc6f516013aaecf856867e446adaeda9c647f79cdcf3e31cb9ffb9068780bd", kill_on_drop: false }`
[INFO] [stdout] 5dbc6f516013aaecf856867e446adaeda9c647f79cdcf3e31cb9ffb9068780bd
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:4f92631de1aa59f8320307485d3b3c869a5c90ab1d76ce2cffab9807b8c9a1fb" "/opt/rustwide/cargo-home/bin/cargo" "+f82664191d0e8764b7435b9d72eb0e366b8b1464" "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] dec72afb820491c9a1fdcedeb170905aaba99e5990644347a07b3d685527d0b5
[INFO] running `Command { std: "docker" "start" "-a" "dec72afb820491c9a1fdcedeb170905aaba99e5990644347a07b3d685527d0b5", kill_on_drop: false }`
[INFO] [stderr]     Checking getrandom v0.2.2
[INFO] [stderr]     Checking rand_core v0.6.2
[INFO] [stderr]     Checking rand_chacha v0.3.0
[INFO] [stderr]     Checking rand v0.8.3
[INFO] [stderr]     Checking fretboard v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `thread_rng`
[INFO] [stdout]  --> src/main.rs:1:17
[INFO] [stdout]   |
[INFO] [stdout] 1 | use rand::{Rng, thread_rng};
[INFO] [stdout]   |                 ^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `thread_rng`
[INFO] [stdout]  --> src/main.rs:1:17
[INFO] [stdout]   |
[INFO] [stdout] 1 | use rand::{Rng, thread_rng};
[INFO] [stdout]   |                 ^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `question_string_index` is never read
[INFO] [stdout]   --> src/main.rs:27:13
[INFO] [stdout]    |
[INFO] [stdout] 27 |     let mut question_string_index: usize = high_range;
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout]    = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `question_note_index` is never read
[INFO] [stdout]   --> src/main.rs:28:13
[INFO] [stdout]    |
[INFO] [stdout] 28 |     let mut question_note_index: usize = 7;
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `question_string_index` is never read
[INFO] [stdout]   --> src/main.rs:27:13
[INFO] [stdout]    |
[INFO] [stdout] 27 |     let mut question_string_index: usize = high_range;
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout]    = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `question_note_index` is never read
[INFO] [stdout]   --> src/main.rs:28:13
[INFO] [stdout]    |
[INFO] [stdout] 28 |     let mut question_note_index: usize = 7;
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 2.97s
[INFO] running `Command { std: "docker" "inspect" "dec72afb820491c9a1fdcedeb170905aaba99e5990644347a07b3d685527d0b5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "dec72afb820491c9a1fdcedeb170905aaba99e5990644347a07b3d685527d0b5", kill_on_drop: false }`
[INFO] [stdout] dec72afb820491c9a1fdcedeb170905aaba99e5990644347a07b3d685527d0b5