[INFO] cloning repository https://github.com/0xSaksham/reference_cycle
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/0xSaksham/reference_cycle" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2F0xSaksham%2Freference_cycle", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2F0xSaksham%2Freference_cycle'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 40b970ebecf94381b3a4a19e2b6eef99f12595d7
[INFO] testing 0xSaksham/reference_cycle against master#733b47ea4b1b86216f14ef56e49440c33933f230+rustflags=-Copt-level=3 for pr-138759
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2F0xSaksham%2Freference_cycle" "/workspace/builds/worker-5-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-5-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/0xSaksham/reference_cycle
[INFO] finished tweaking git repo https://github.com/0xSaksham/reference_cycle
[INFO] tweaked toml for git repo https://github.com/0xSaksham/reference_cycle written to /workspace/builds/worker-5-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/0xSaksham/reference_cycle on toolchain 733b47ea4b1b86216f14ef56e49440c33933f230
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+733b47ea4b1b86216f14ef56e49440c33933f230" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/0xSaksham/reference_cycle 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" "+733b47ea4b1b86216f14ef56e49440c33933f230" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+733b47ea4b1b86216f14ef56e49440c33933f230" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 754c3c4205b8034a5fc67780285a5f16bd9b7b3eed02c3f5d2e482a1b5bb28a3
[INFO] running `Command { std: "docker" "start" "-a" "754c3c4205b8034a5fc67780285a5f16bd9b7b3eed02c3f5d2e482a1b5bb28a3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "754c3c4205b8034a5fc67780285a5f16bd9b7b3eed02c3f5d2e482a1b5bb28a3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "754c3c4205b8034a5fc67780285a5f16bd9b7b3eed02c3f5d2e482a1b5bb28a3", kill_on_drop: false }`
[INFO] [stdout] 754c3c4205b8034a5fc67780285a5f16bd9b7b3eed02c3f5d2e482a1b5bb28a3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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 -Copt-level=3" "-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+733b47ea4b1b86216f14ef56e49440c33933f230" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] dffd321e69ade22e4a0dc174a38c5d6beb0ca57dd33800879566f881adc72be7
[INFO] running `Command { std: "docker" "start" "-a" "dffd321e69ade22e4a0dc174a38c5d6beb0ca57dd33800879566f881adc72be7", kill_on_drop: false }`
[INFO] [stderr]    Compiling reference_cycle v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]  --> src/main.rs:6:10
[INFO] [stdout]   |
[INFO] [stdout] 6 |     Cons(i32, RefCell<Rc<List>>),
[INFO] [stdout]   |     ---- ^^^
[INFO] [stdout]   |     |
[INFO] [stdout]   |     field in this variant
[INFO] [stdout]   |
[INFO] [stdout]   = note: `List` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]   |
[INFO] [stdout] 6 -     Cons(i32, RefCell<Rc<List>>),
[INFO] [stdout] 6 +     Cons((), RefCell<Rc<List>>),
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.62s
[INFO] running `Command { std: "docker" "inspect" "dffd321e69ade22e4a0dc174a38c5d6beb0ca57dd33800879566f881adc72be7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "dffd321e69ade22e4a0dc174a38c5d6beb0ca57dd33800879566f881adc72be7", kill_on_drop: false }`
[INFO] [stdout] dffd321e69ade22e4a0dc174a38c5d6beb0ca57dd33800879566f881adc72be7
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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 -Copt-level=3" "-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+733b47ea4b1b86216f14ef56e49440c33933f230" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] df3f7afe7798bc85110c20a7bef588e88d1d89894f7195cd0003efd10ca0e0e7
[INFO] running `Command { std: "docker" "start" "-a" "df3f7afe7798bc85110c20a7bef588e88d1d89894f7195cd0003efd10ca0e0e7", kill_on_drop: false }`
[INFO] [stderr]    Compiling reference_cycle v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]  --> src/main.rs:6:10
[INFO] [stdout]   |
[INFO] [stdout] 6 |     Cons(i32, RefCell<Rc<List>>),
[INFO] [stdout]   |     ---- ^^^
[INFO] [stdout]   |     |
[INFO] [stdout]   |     field in this variant
[INFO] [stdout]   |
[INFO] [stdout]   = note: `List` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]   |
[INFO] [stdout] 6 -     Cons(i32, RefCell<Rc<List>>),
[INFO] [stdout] 6 +     Cons((), RefCell<Rc<List>>),
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.68s
[INFO] running `Command { std: "docker" "inspect" "df3f7afe7798bc85110c20a7bef588e88d1d89894f7195cd0003efd10ca0e0e7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "df3f7afe7798bc85110c20a7bef588e88d1d89894f7195cd0003efd10ca0e0e7", kill_on_drop: false }`
[INFO] [stdout] df3f7afe7798bc85110c20a7bef588e88d1d89894f7195cd0003efd10ca0e0e7
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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 -Copt-level=3" "-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+733b47ea4b1b86216f14ef56e49440c33933f230" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] e747c18a880211624868e56318322e89be18b114877865bff236526e1130a245
[INFO] running `Command { std: "docker" "start" "-a" "e747c18a880211624868e56318322e89be18b114877865bff236526e1130a245", kill_on_drop: false }`
[INFO] [stderr] warning: field `0` is never read
[INFO] [stderr]  --> src/main.rs:6:10
[INFO] [stderr]   |
[INFO] [stderr] 6 |     Cons(i32, RefCell<Rc<List>>),
[INFO] [stderr]   |     ---- ^^^
[INFO] [stderr]   |     |
[INFO] [stderr]   |     field in this variant
[INFO] [stderr]   |
[INFO] [stderr]   = note: `List` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stderr]   = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stderr]   |
[INFO] [stderr] 6 -     Cons(i32, RefCell<Rc<List>>),
[INFO] [stderr] 6 +     Cons((), RefCell<Rc<List>>),
[INFO] [stderr]   |
[INFO] [stderr] 
[INFO] [stderr] warning: `reference_cycle` (bin "reference_cycle" test) generated 1 warning
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.02s
[INFO] [stderr]      Running unittests src/main.rs (/opt/rustwide/target/debug/deps/reference_cycle-cb2b6ff6c220aeb5)
[INFO] [stdout] 
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "e747c18a880211624868e56318322e89be18b114877865bff236526e1130a245", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e747c18a880211624868e56318322e89be18b114877865bff236526e1130a245", kill_on_drop: false }`
[INFO] [stdout] e747c18a880211624868e56318322e89be18b114877865bff236526e1130a245
