[INFO] cloning repository https://github.com/varleg/multithread_ticket_sales
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/varleg/multithread_ticket_sales" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fvarleg%2Fmultithread_ticket_sales", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fvarleg%2Fmultithread_ticket_sales'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 2a22f9ee5441c74a4970241b01d019d1e758c91b
[INFO] checking varleg/multithread_ticket_sales against try#4f260f0f20b3133d20cfb50353c0221943af5796+rustflags=-Dunmustuse_in_always_ok for pr-148577
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fvarleg%2Fmultithread_ticket_sales" "/workspace/builds/worker-3-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/varleg/multithread_ticket_sales
[INFO] finished tweaking git repo https://github.com/varleg/multithread_ticket_sales
[INFO] tweaked toml for git repo https://github.com/varleg/multithread_ticket_sales written to /workspace/builds/worker-3-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/varleg/multithread_ticket_sales on toolchain 4f260f0f20b3133d20cfb50353c0221943af5796
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/varleg/multithread_ticket_sales 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" "+4f260f0f20b3133d20cfb50353c0221943af5796" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded libc v0.2.55
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 7f685db60265ac0c2b7eed23559bed2891d1d96c61188123ca335e1dc6d4e580
[INFO] running `Command { std: "docker" "start" "-a" "7f685db60265ac0c2b7eed23559bed2891d1d96c61188123ca335e1dc6d4e580", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7f685db60265ac0c2b7eed23559bed2891d1d96c61188123ca335e1dc6d4e580", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7f685db60265ac0c2b7eed23559bed2891d1d96c61188123ca335e1dc6d4e580", kill_on_drop: false }`
[INFO] [stdout] 7f685db60265ac0c2b7eed23559bed2891d1d96c61188123ca335e1dc6d4e580
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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 -Dunmustuse_in_always_ok" "-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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 1de4d86059feb63391ffaadcaaaea0b6b7cbc244857f475b81c88fea6d0b29e5
[INFO] running `Command { std: "docker" "start" "-a" "1de4d86059feb63391ffaadcaaaea0b6b7cbc244857f475b81c88fea6d0b29e5", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.55
[INFO] [stderr]     Checking rand_os v0.1.3
[INFO] [stderr]     Checking num_cpus v1.10.0
[INFO] [stderr]     Checking rand v0.6.5
[INFO] [stderr]     Checking ticket_master v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:21:17
[INFO] [stdout]    |
[INFO] [stdout] 21 | fn ticket_sales(mut box_office: &mut BoxOffice, ticket_id: usize, amount: i32) {
[INFO] [stdout]    |                 ----^^^^^^^^^^
[INFO] [stdout]    |                 |
[INFO] [stdout]    |                 help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:22:9
[INFO] [stdout]    |
[INFO] [stdout] 22 |     let mut ticket = &mut box_office.tickets[ticket_id];
[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/main.rs:21:17
[INFO] [stdout]    |
[INFO] [stdout] 21 | fn ticket_sales(mut box_office: &mut BoxOffice, ticket_id: usize, amount: i32) {
[INFO] [stdout]    |                 ----^^^^^^^^^^
[INFO] [stdout]    |                 |
[INFO] [stdout]    |                 help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:22:9
[INFO] [stdout]    |
[INFO] [stdout] 22 |     let mut ticket = &mut box_office.tickets[ticket_id];
[INFO] [stdout]    |         ----^^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 1.90s
[INFO] running `Command { std: "docker" "inspect" "1de4d86059feb63391ffaadcaaaea0b6b7cbc244857f475b81c88fea6d0b29e5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1de4d86059feb63391ffaadcaaaea0b6b7cbc244857f475b81c88fea6d0b29e5", kill_on_drop: false }`
[INFO] [stdout] 1de4d86059feb63391ffaadcaaaea0b6b7cbc244857f475b81c88fea6d0b29e5