[INFO] cloning repository https://github.com/googlercolin/Rust_program_optimization
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/googlercolin/Rust_program_optimization" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fgooglercolin%2FRust_program_optimization", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fgooglercolin%2FRust_program_optimization'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 67d4c75b8df987640dd599ff883d8904fb071fd3
[INFO] checking googlercolin/Rust_program_optimization against try#a2a6e871b05c7b8ecc9a3c8a20db1f39e995e399 for pr-145770
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fgooglercolin%2FRust_program_optimization" "/workspace/builds/worker-6-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/googlercolin/Rust_program_optimization
[INFO] finished tweaking git repo https://github.com/googlercolin/Rust_program_optimization
[INFO] tweaked toml for git repo https://github.com/googlercolin/Rust_program_optimization written to /workspace/builds/worker-6-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/googlercolin/Rust_program_optimization on toolchain a2a6e871b05c7b8ecc9a3c8a20db1f39e995e399
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+a2a6e871b05c7b8ecc9a3c8a20db1f39e995e399" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/googlercolin/Rust_program_optimization 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" "+a2a6e871b05c7b8ecc9a3c8a20db1f39e995e399" "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-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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@sha256:7ad1b28ee6f5f7f699f6cf7015098d6ccdd96d6f2d78dd06228f5b4c9faf309c" "/opt/rustwide/cargo-home/bin/cargo" "+a2a6e871b05c7b8ecc9a3c8a20db1f39e995e399" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] ea1a4bc394cc8aa93d5fd7c91cf96919057b691b63f1b5becdfe286394109c8f
[INFO] running `Command { std: "docker" "start" "-a" "ea1a4bc394cc8aa93d5fd7c91cf96919057b691b63f1b5becdfe286394109c8f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ea1a4bc394cc8aa93d5fd7c91cf96919057b691b63f1b5becdfe286394109c8f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ea1a4bc394cc8aa93d5fd7c91cf96919057b691b63f1b5becdfe286394109c8f", kill_on_drop: false }`
[INFO] [stdout] ea1a4bc394cc8aa93d5fd7c91cf96919057b691b63f1b5becdfe286394109c8f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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@sha256:7ad1b28ee6f5f7f699f6cf7015098d6ccdd96d6f2d78dd06228f5b4c9faf309c" "/opt/rustwide/cargo-home/bin/cargo" "+a2a6e871b05c7b8ecc9a3c8a20db1f39e995e399" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 9f427563a69df383450193bee0d542febbf39194d8cc7725a54cb5d4a168f0c8
[INFO] running `Command { std: "docker" "start" "-a" "9f427563a69df383450193bee0d542febbf39194d8cc7725a54cb5d4a168f0c8", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v1.0.0
[INFO] [stderr]    Compiling maybe-uninit v2.0.0
[INFO] [stderr]    Compiling typenum v1.12.0
[INFO] [stderr]    Compiling version_check v0.9.2
[INFO] [stderr]     Checking scopeguard v1.1.0
[INFO] [stderr]     Checking opaque-debug v0.3.0
[INFO] [stderr]     Checking cpuid-bool v0.1.2
[INFO] [stderr]     Checking hex v0.4.2
[INFO] [stderr]    Compiling generic-array v0.14.4
[INFO] [stderr]    Compiling crossbeam-utils v0.7.2
[INFO] [stderr]    Compiling memoffset v0.5.5
[INFO] [stderr]    Compiling crossbeam-epoch v0.8.2
[INFO] [stderr]     Checking crossbeam-queue v0.2.3
[INFO] [stderr]     Checking crossbeam-channel v0.4.3
[INFO] [stderr]     Checking crossbeam-deque v0.7.3
[INFO] [stderr]     Checking block-buffer v0.9.0
[INFO] [stderr]     Checking digest v0.9.0
[INFO] [stderr]     Checking crossbeam v0.7.3
[INFO] [stderr]     Checking sha2 v0.9.1
[INFO] [stderr]     Checking lab4 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: field `num_pkgs` is never read
[INFO] [stdout]   --> src/idea.rs:17:5
[INFO] [stdout]    |
[INFO] [stdout] 13 | pub struct IdeaGenerator {
[INFO] [stdout]    |            ------------- field in this struct
[INFO] [stdout] ...
[INFO] [stdout] 17 |     num_pkgs: usize,
[INFO] [stdout]    |     ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `id` is never read
[INFO] [stdout]  --> src/student.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | pub struct Student {
[INFO] [stdout]   |            ------- field in this struct
[INFO] [stdout] 6 |     id: usize,
[INFO] [stdout]   |     ^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `num_pkgs` is never read
[INFO] [stdout]   --> src/idea.rs:17:5
[INFO] [stdout]    |
[INFO] [stdout] 13 | pub struct IdeaGenerator {
[INFO] [stdout]    |            ------------- field in this struct
[INFO] [stdout] ...
[INFO] [stdout] 17 |     num_pkgs: usize,
[INFO] [stdout]    |     ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `id` is never read
[INFO] [stdout]  --> src/student.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | pub struct Student {
[INFO] [stdout]   |            ------- field in this struct
[INFO] [stdout] 6 |     id: usize,
[INFO] [stdout]   |     ^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/main.rs:153:9
[INFO] [stdout]     |
[INFO] [stdout] 153 |         idea_send.send(Event::OutOfIdeas);
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 153 |         let _ = idea_send.send(Event::OutOfIdeas);
[INFO] [stdout]     |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/main.rs:153:9
[INFO] [stdout]     |
[INFO] [stdout] 153 |         idea_send.send(Event::OutOfIdeas);
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 153 |         let _ = idea_send.send(Event::OutOfIdeas);
[INFO] [stdout]     |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 3.21s
[INFO] running `Command { std: "docker" "inspect" "9f427563a69df383450193bee0d542febbf39194d8cc7725a54cb5d4a168f0c8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9f427563a69df383450193bee0d542febbf39194d8cc7725a54cb5d4a168f0c8", kill_on_drop: false }`
[INFO] [stdout] 9f427563a69df383450193bee0d542febbf39194d8cc7725a54cb5d4a168f0c8
