[INFO] cloning repository https://github.com/rchaser53/macro-playground
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/rchaser53/macro-playground" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frchaser53%2Fmacro-playground", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frchaser53%2Fmacro-playground'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 732eba4d3f7e76eef5ad305672687f9a1e224e27
[INFO] checking rchaser53/macro-playground against master#936f2600b6c903b04387f74ed5cbce88bb06d243 for pr-91141
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frchaser53%2Fmacro-playground" "/workspace/builds/worker-22/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-22/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/rchaser53/macro-playground on toolchain 936f2600b6c903b04387f74ed5cbce88bb06d243
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+936f2600b6c903b04387f74ed5cbce88bb06d243" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/rchaser53/macro-playground
[INFO] finished tweaking git repo https://github.com/rchaser53/macro-playground
[INFO] tweaked toml for git repo https://github.com/rchaser53/macro-playground written to /workspace/builds/worker-22/source/Cargo.toml
[INFO] crate git repo https://github.com/rchaser53/macro-playground already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+936f2600b6c903b04387f74ed5cbce88bb06d243" "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-22/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-22/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@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+936f2600b6c903b04387f74ed5cbce88bb06d243" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] c487755ffd445f580e9cc39e3365b97ca95569e35b457f32711148a7704df42d
[INFO] running `Command { std: "docker" "start" "-a" "c487755ffd445f580e9cc39e3365b97ca95569e35b457f32711148a7704df42d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c487755ffd445f580e9cc39e3365b97ca95569e35b457f32711148a7704df42d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c487755ffd445f580e9cc39e3365b97ca95569e35b457f32711148a7704df42d", kill_on_drop: false }`
[INFO] [stdout] c487755ffd445f580e9cc39e3365b97ca95569e35b457f32711148a7704df42d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-22/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-22/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+936f2600b6c903b04387f74ed5cbce88bb06d243" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] e980d41216e777e727109767c1cac62b96893bff001a8743659dffdb5defc60f
[INFO] running `Command { std: "docker" "start" "-a" "e980d41216e777e727109767c1cac62b96893bff001a8743659dffdb5defc60f", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking macro-playground v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::error::Error`
[INFO] [stdout]  --> src/main.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::error::Error;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::error::Error`
[INFO] [stdout]  --> src/main.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::error::Error;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `id`
[INFO] [stdout]  --> src/main.rs:9:3
[INFO] [stdout]   |
[INFO] [stdout] 9 |   id: usize,
[INFO] [stdout]   |   ^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/main.rs:38:3
[INFO] [stdout]    |
[INFO] [stdout] 38 |   &parent.add_child(weak_parent);
[INFO] [stdout]    |   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 38 |   let _ = &parent.add_child(weak_parent);
[INFO] [stdout]    |   +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `id`
[INFO] [stdout]  --> src/main.rs:9:3
[INFO] [stdout]   |
[INFO] [stdout] 9 |   id: usize,
[INFO] [stdout]   |   ^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/main.rs:38:3
[INFO] [stdout]    |
[INFO] [stdout] 38 |   &parent.add_child(weak_parent);
[INFO] [stdout]    |   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 38 |   let _ = &parent.add_child(weak_parent);
[INFO] [stdout]    |   +++++++
[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 8.51s
[INFO] running `Command { std: "docker" "inspect" "e980d41216e777e727109767c1cac62b96893bff001a8743659dffdb5defc60f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e980d41216e777e727109767c1cac62b96893bff001a8743659dffdb5defc60f", kill_on_drop: false }`
[INFO] [stdout] e980d41216e777e727109767c1cac62b96893bff001a8743659dffdb5defc60f