[INFO] cloning repository https://github.com/etch1000/reference_counting
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/etch1000/reference_counting" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fetch1000%2Freference_counting", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fetch1000%2Freference_counting'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 8bd41678c3b47c6b9095b222f43976b20bfde4ba
[INFO] checking etch1000/reference_counting against try#b32fc44666c052e7cf07ab471bfb6f9ec571902f for pr-138676
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fetch1000%2Freference_counting" "/workspace/builds/worker-4-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/etch1000/reference_counting on toolchain b32fc44666c052e7cf07ab471bfb6f9ec571902f
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+b32fc44666c052e7cf07ab471bfb6f9ec571902f" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/etch1000/reference_counting
[INFO] finished tweaking git repo https://github.com/etch1000/reference_counting
[INFO] tweaked toml for git repo https://github.com/etch1000/reference_counting written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/etch1000/reference_counting 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" "+b32fc44666c052e7cf07ab471bfb6f9ec571902f" "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] checking etch1000/reference_counting against try#b32fc44666c052e7cf07ab471bfb6f9ec571902f for pr-138676
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fetch1000%2Freference_counting" "/workspace/builds/worker-4-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/etch1000/reference_counting on toolchain b32fc44666c052e7cf07ab471bfb6f9ec571902f
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+b32fc44666c052e7cf07ab471bfb6f9ec571902f" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/etch1000/reference_counting
[INFO] finished tweaking git repo https://github.com/etch1000/reference_counting
[INFO] tweaked toml for git repo https://github.com/etch1000/reference_counting written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/etch1000/reference_counting 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" "+b32fc44666c052e7cf07ab471bfb6f9ec571902f" "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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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@sha256:1680c8fbd8dfb46fcd6d22e546df16ab0e007457dc29fcd9e987cdd5077fd1af" "/opt/rustwide/cargo-home/bin/cargo" "+b32fc44666c052e7cf07ab471bfb6f9ec571902f" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] Error response from daemon: mkdir /var/lib/docker/overlay2/95a5b0364a4ebb8c928ebc105e62eeeb2531c15a3a86b01f6a6c50cab26f32db-init/merged/dev/pts: no space left on device
[INFO] checking etch1000/reference_counting against try#b32fc44666c052e7cf07ab471bfb6f9ec571902f for pr-138676
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fetch1000%2Freference_counting" "/workspace/builds/worker-4-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc2/source'...
[INFO] [stderr] /workspace/builds/worker-4-tc2/source/.git/info/: No space left on device
[INFO] checking etch1000/reference_counting against try#b32fc44666c052e7cf07ab471bfb6f9ec571902f for pr-138676
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fetch1000%2Freference_counting" "/workspace/builds/worker-4-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/etch1000/reference_counting on toolchain b32fc44666c052e7cf07ab471bfb6f9ec571902f
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+b32fc44666c052e7cf07ab471bfb6f9ec571902f" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/etch1000/reference_counting
[INFO] finished tweaking git repo https://github.com/etch1000/reference_counting
[INFO] tweaked toml for git repo https://github.com/etch1000/reference_counting written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/etch1000/reference_counting 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" "+b32fc44666c052e7cf07ab471bfb6f9ec571902f" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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@sha256:1680c8fbd8dfb46fcd6d22e546df16ab0e007457dc29fcd9e987cdd5077fd1af" "/opt/rustwide/cargo-home/bin/cargo" "+b32fc44666c052e7cf07ab471bfb6f9ec571902f" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 1a024149b4ae62e5904377b04e8e139f4189d2cad422bdde49a2c932b18d296c
[INFO] running `Command { std: "docker" "start" "-a" "1a024149b4ae62e5904377b04e8e139f4189d2cad422bdde49a2c932b18d296c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "1a024149b4ae62e5904377b04e8e139f4189d2cad422bdde49a2c932b18d296c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1a024149b4ae62e5904377b04e8e139f4189d2cad422bdde49a2c932b18d296c", kill_on_drop: false }`
[INFO] [stdout] 1a024149b4ae62e5904377b04e8e139f4189d2cad422bdde49a2c932b18d296c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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@sha256:1680c8fbd8dfb46fcd6d22e546df16ab0e007457dc29fcd9e987cdd5077fd1af" "/opt/rustwide/cargo-home/bin/cargo" "+b32fc44666c052e7cf07ab471bfb6f9ec571902f" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 0384e285cf6412d121aa5faf2f89ccb2f72bb09dec013b6eac3b54e10cf2ca8a
[INFO] running `Command { std: "docker" "start" "-a" "0384e285cf6412d121aa5faf2f89ccb2f72bb09dec013b6eac3b54e10cf2ca8a", kill_on_drop: false }`
[INFO] [stderr]     Checking reference_counting v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]  --> src/main.rs:9:10
[INFO] [stdout]   |
[INFO] [stdout] 9 |     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] 9 -     Cons(i32, RefCell<Rc<List>>),
[INFO] [stdout] 9 +     Cons((), RefCell<Rc<List>>),
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]  --> src/main.rs:9:10
[INFO] [stdout]   |
[INFO] [stdout] 9 |     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] 9 -     Cons(i32, RefCell<Rc<List>>),
[INFO] [stdout] 9 +     Cons((), RefCell<Rc<List>>),
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.12s
[INFO] running `Command { std: "docker" "inspect" "0384e285cf6412d121aa5faf2f89ccb2f72bb09dec013b6eac3b54e10cf2ca8a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0384e285cf6412d121aa5faf2f89ccb2f72bb09dec013b6eac3b54e10cf2ca8a", kill_on_drop: false }`
[INFO] [stdout] 0384e285cf6412d121aa5faf2f89ccb2f72bb09dec013b6eac3b54e10cf2ca8a