[INFO] fetching crate koi-gc 0.1.0...
[INFO] testing koi-gc-0.1.0 against master#0d162b25edd5bf0dba9a22e83b614f1113e90474 for pr-150681
[INFO] extracting crate koi-gc 0.1.0 into /workspace/builds/worker-1-tc1/source
[INFO] started tweaking crates.io crate koi-gc 0.1.0
[INFO] finished tweaking crates.io crate koi-gc 0.1.0
[INFO] tweaked toml for crates.io crate koi-gc 0.1.0 written to /workspace/builds/worker-1-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate koi-gc 0.1.0 on toolchain 0d162b25edd5bf0dba9a22e83b614f1113e90474
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+0d162b25edd5bf0dba9a22e83b614f1113e90474" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate koi-gc 0.1.0 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" "+0d162b25edd5bf0dba9a22e83b614f1113e90474" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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@sha256:845e597a41426bbf2703be69acdb67d10b6de511142d05cba7bbe119c898b2c7" "/opt/rustwide/cargo-home/bin/cargo" "+0d162b25edd5bf0dba9a22e83b614f1113e90474" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] de041c73c4f712012ecc841af992c120ae43606efd148bb86dd830f41b85b030
[INFO] running `Command { std: "docker" "start" "-a" "de041c73c4f712012ecc841af992c120ae43606efd148bb86dd830f41b85b030", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "de041c73c4f712012ecc841af992c120ae43606efd148bb86dd830f41b85b030", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "de041c73c4f712012ecc841af992c120ae43606efd148bb86dd830f41b85b030", kill_on_drop: false }`
[INFO] [stdout] de041c73c4f712012ecc841af992c120ae43606efd148bb86dd830f41b85b030
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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" "-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@sha256:845e597a41426bbf2703be69acdb67d10b6de511142d05cba7bbe119c898b2c7" "/opt/rustwide/cargo-home/bin/cargo" "+0d162b25edd5bf0dba9a22e83b614f1113e90474" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] e3ed807b7f344a5db431ec76abbf23d3ec517b1991c75dc954ec1c00a1ae7dda
[INFO] running `Command { std: "docker" "start" "-a" "e3ed807b7f344a5db431ec76abbf23d3ec517b1991c75dc954ec1c00a1ae7dda", kill_on_drop: false }`
[INFO] [stderr]    Compiling koi-gc v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.57s
[INFO] running `Command { std: "docker" "inspect" "e3ed807b7f344a5db431ec76abbf23d3ec517b1991c75dc954ec1c00a1ae7dda", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e3ed807b7f344a5db431ec76abbf23d3ec517b1991c75dc954ec1c00a1ae7dda", kill_on_drop: false }`
[INFO] [stdout] e3ed807b7f344a5db431ec76abbf23d3ec517b1991c75dc954ec1c00a1ae7dda
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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" "-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@sha256:845e597a41426bbf2703be69acdb67d10b6de511142d05cba7bbe119c898b2c7" "/opt/rustwide/cargo-home/bin/cargo" "+0d162b25edd5bf0dba9a22e83b614f1113e90474" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 49e97c5ddc8c0f4926b372670d8b8d7813e338ed3a86cebe7965a8a8544a70c4
[INFO] running `Command { std: "docker" "start" "-a" "49e97c5ddc8c0f4926b372670d8b8d7813e338ed3a86cebe7965a8a8544a70c4", kill_on_drop: false }`
[INFO] [stderr]    Compiling koi-gc v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `visitor`
[INFO] [stdout]    --> src/lib.rs:486:29
[INFO] [stdout]     |
[INFO] [stdout] 486 |             fn visit(&self, visitor: &mut dyn FnMut(&dyn GcInterface)) {}
[INFO] [stdout]     |                             ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_visitor`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `data` is never read
[INFO] [stdout]    --> src/lib.rs:440:9
[INFO] [stdout]     |
[INFO] [stdout] 438 |     struct Leak<T> {
[INFO] [stdout]     |            ---- field in this struct
[INFO] [stdout] 439 |         cycle: RefCell<Option<Rc<Rc<Leak<T>>>>>,
[INFO] [stdout] 440 |         data: T,
[INFO] [stdout]     |         ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.88s
[INFO] running `Command { std: "docker" "inspect" "49e97c5ddc8c0f4926b372670d8b8d7813e338ed3a86cebe7965a8a8544a70c4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "49e97c5ddc8c0f4926b372670d8b8d7813e338ed3a86cebe7965a8a8544a70c4", kill_on_drop: false }`
[INFO] [stdout] 49e97c5ddc8c0f4926b372670d8b8d7813e338ed3a86cebe7965a8a8544a70c4
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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" "-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@sha256:845e597a41426bbf2703be69acdb67d10b6de511142d05cba7bbe119c898b2c7" "/opt/rustwide/cargo-home/bin/cargo" "+0d162b25edd5bf0dba9a22e83b614f1113e90474" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 7aedca9ba34c080c0e72f0f66f5bdf0818ea636f1a4b524db61f5608f76f62b9
[INFO] running `Command { std: "docker" "start" "-a" "7aedca9ba34c080c0e72f0f66f5bdf0818ea636f1a4b524db61f5608f76f62b9", kill_on_drop: false }`
[INFO] [stderr] warning: unused variable: `visitor`
[INFO] [stderr]    --> src/lib.rs:486:29
[INFO] [stderr]     |
[INFO] [stderr] 486 |             fn visit(&self, visitor: &mut dyn FnMut(&dyn GcInterface)) {}
[INFO] [stderr]     |                             ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_visitor`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stderr] 
[INFO] [stderr] warning: field `data` is never read
[INFO] [stderr]    --> src/lib.rs:440:9
[INFO] [stderr]     |
[INFO] [stderr] 438 |     struct Leak<T> {
[INFO] [stderr]     |            ---- field in this struct
[INFO] [stderr] 439 |         cycle: RefCell<Option<Rc<Rc<Leak<T>>>>>,
[INFO] [stderr] 440 |         data: T,
[INFO] [stderr]     |         ^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stderr] 
[INFO] [stderr] warning: `koi-gc` (lib test) generated 2 warnings (run `cargo fix --lib -p koi-gc --tests` to apply 1 suggestion)
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.21s
[INFO] [stderr]      Running unittests src/lib.rs (/opt/rustwide/target/debug/deps/koi_gc-eeaf49799adba8f7)
[INFO] [stdout] 
[INFO] [stdout] running 2 tests
[INFO] [stdout] test tests::test_cycle_collection ... ok
[INFO] [stderr] error: test failed, to rerun pass `--lib`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `/opt/rustwide/target/debug/deps/koi_gc-eeaf49799adba8f7` (signal: 11, SIGSEGV: invalid memory reference)
[INFO] running `Command { std: "docker" "inspect" "7aedca9ba34c080c0e72f0f66f5bdf0818ea636f1a4b524db61f5608f76f62b9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7aedca9ba34c080c0e72f0f66f5bdf0818ea636f1a4b524db61f5608f76f62b9", kill_on_drop: false }`
[INFO] [stdout] 7aedca9ba34c080c0e72f0f66f5bdf0818ea636f1a4b524db61f5608f76f62b9