[INFO] cloning repository https://github.com/bkerz/rust-exercises
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/bkerz/rust-exercises" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbkerz%2Frust-exercises", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbkerz%2Frust-exercises'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 5e784bdfbe73342b253b55f9656e640eca7c8ecc
[INFO] building bkerz/rust-exercises against master#11663cd3bfefef7d34e8f0892c250bf698049392+rustflags=-Dtail-expr-drop-order for pr-134523
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbkerz%2Frust-exercises" "/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/bkerz/rust-exercises on toolchain 11663cd3bfefef7d34e8f0892c250bf698049392
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/bkerz/rust-exercises
[INFO] finished tweaking git repo https://github.com/bkerz/rust-exercises
[INFO] tweaked toml for git repo https://github.com/bkerz/rust-exercises written to /workspace/builds/worker-0-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/bkerz/rust-exercises 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" "+11663cd3bfefef7d34e8f0892c250bf698049392" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 29ed3539fbc63c9734be09a7850918999f646c278c962f9cfb5efdaac40aab0c
[INFO] running `Command { std: "docker" "start" "-a" "29ed3539fbc63c9734be09a7850918999f646c278c962f9cfb5efdaac40aab0c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "29ed3539fbc63c9734be09a7850918999f646c278c962f9cfb5efdaac40aab0c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "29ed3539fbc63c9734be09a7850918999f646c278c962f9cfb5efdaac40aab0c", kill_on_drop: false }`
[INFO] [stdout] 29ed3539fbc63c9734be09a7850918999f646c278c962f9cfb5efdaac40aab0c
[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 -Dtail-expr-drop-order" "-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] ceb58e3a22da335ddf7b8b3611b1f125ae679bfbcdfa98b5a4e89eb4b5254246
[INFO] running `Command { std: "docker" "start" "-a" "ceb58e3a22da335ddf7b8b3611b1f125ae679bfbcdfa98b5a4e89eb4b5254246", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.153
[INFO] [stderr]    Compiling powerfmt v0.2.0
[INFO] [stderr]    Compiling time-core v0.1.2
[INFO] [stderr]    Compiling num-conv v0.1.0
[INFO] [stderr]    Compiling deranged v0.3.11
[INFO] [stderr]    Compiling time v0.3.34
[INFO] [stderr]    Compiling getrandom v0.2.12
[INFO] [stderr]    Compiling rand_core v0.6.4
[INFO] [stderr]    Compiling rand_chacha v0.3.1
[INFO] [stderr]    Compiling rand v0.8.5
[INFO] [stderr]    Compiling exercise v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `rand::Rng`
[INFO] [stdout]   --> src/main.rs:10:5
[INFO] [stdout]    |
[INFO] [stdout] 10 | use rand::Rng;
[INFO] [stdout]    |     ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::fmt`
[INFO] [stdout]   --> src/main.rs:11:5
[INFO] [stdout]    |
[INFO] [stdout] 11 | use std::fmt;
[INFO] [stdout]    |     ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Sender`
[INFO] [stdout]   --> src/main.rs:12:29
[INFO] [stdout]    |
[INFO] [stdout] 12 | use std::sync::mpsc::{self, Sender};
[INFO] [stdout]    |                             ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `mpsc::Sender`
[INFO] [stdout]  --> src/threadpool.rs:5:12
[INFO] [stdout]   |
[INFO] [stdout] 5 |     sync::{mpsc::Sender, Arc, Mutex, MutexGuard},
[INFO] [stdout]   |            ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `tx`
[INFO] [stdout]   --> src/main.rs:22:9
[INFO] [stdout]    |
[INFO] [stdout] 22 |     let tx = Arc::new(Mutex::new(tx));
[INFO] [stdout]    |         ^^ help: if this is intentional, prefix it with an underscore: `_tx`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 2.92s
[INFO] running `Command { std: "docker" "inspect" "ceb58e3a22da335ddf7b8b3611b1f125ae679bfbcdfa98b5a4e89eb4b5254246", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ceb58e3a22da335ddf7b8b3611b1f125ae679bfbcdfa98b5a4e89eb4b5254246", kill_on_drop: false }`
[INFO] [stdout] ceb58e3a22da335ddf7b8b3611b1f125ae679bfbcdfa98b5a4e89eb4b5254246
[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 -Dtail-expr-drop-order" "-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 3cf2dd231582c1315043235f5f211701b5864fe0111ae7e1a686a3f4a7b36d55
[INFO] running `Command { std: "docker" "start" "-a" "3cf2dd231582c1315043235f5f211701b5864fe0111ae7e1a686a3f4a7b36d55", kill_on_drop: false }`
[INFO] [stderr]    Compiling exercise v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `rand::Rng`
[INFO] [stdout]   --> src/main.rs:10:5
[INFO] [stdout]    |
[INFO] [stdout] 10 | use rand::Rng;
[INFO] [stdout]    |     ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::fmt`
[INFO] [stdout]   --> src/main.rs:11:5
[INFO] [stdout]    |
[INFO] [stdout] 11 | use std::fmt;
[INFO] [stdout]    |     ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Sender`
[INFO] [stdout]   --> src/main.rs:12:29
[INFO] [stdout]    |
[INFO] [stdout] 12 | use std::sync::mpsc::{self, Sender};
[INFO] [stdout]    |                             ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `mpsc::Sender`
[INFO] [stdout]  --> src/threadpool.rs:5:12
[INFO] [stdout]   |
[INFO] [stdout] 5 |     sync::{mpsc::Sender, Arc, Mutex, MutexGuard},
[INFO] [stdout]   |            ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `tx`
[INFO] [stdout]   --> src/main.rs:22:9
[INFO] [stdout]    |
[INFO] [stdout] 22 |     let tx = Arc::new(Mutex::new(tx));
[INFO] [stdout]    |         ^^ help: if this is intentional, prefix it with an underscore: `_tx`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.14s
[INFO] running `Command { std: "docker" "inspect" "3cf2dd231582c1315043235f5f211701b5864fe0111ae7e1a686a3f4a7b36d55", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3cf2dd231582c1315043235f5f211701b5864fe0111ae7e1a686a3f4a7b36d55", kill_on_drop: false }`
[INFO] [stdout] 3cf2dd231582c1315043235f5f211701b5864fe0111ae7e1a686a3f4a7b36d55