[INFO] updating cached repository isaacazuelos/rs_gc_dead_end
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/isaacazuelos/rs_gc_dead_end
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/isaacazuelos/rs_gc_dead_end" "work/ex/beta-1.37-6/sources/1.36.0/gh/isaacazuelos/rs_gc_dead_end"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.37-6/sources/1.36.0/gh/isaacazuelos/rs_gc_dead_end'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/isaacazuelos/rs_gc_dead_end" "work/ex/beta-1.37-6/sources/beta-2019-07-23/gh/isaacazuelos/rs_gc_dead_end"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.37-6/sources/beta-2019-07-23/gh/isaacazuelos/rs_gc_dead_end'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 38eb6324bcc278465b11a905cc72a55e380626c3
[INFO] sha for GitHub repo isaacazuelos/rs_gc_dead_end: 38eb6324bcc278465b11a905cc72a55e380626c3
[INFO] validating manifest of isaacazuelos/rs_gc_dead_end on toolchain 1.36.0
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.36.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of isaacazuelos/rs_gc_dead_end on toolchain beta-2019-07-23
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-07-23" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing isaacazuelos/rs_gc_dead_end
[INFO] finished frobbing isaacazuelos/rs_gc_dead_end
[INFO] frobbed toml for isaacazuelos/rs_gc_dead_end written to work/ex/beta-1.37-6/sources/1.36.0/gh/isaacazuelos/rs_gc_dead_end/Cargo.toml
[INFO] started frobbing isaacazuelos/rs_gc_dead_end
[INFO] finished frobbing isaacazuelos/rs_gc_dead_end
[INFO] frobbed toml for isaacazuelos/rs_gc_dead_end written to work/ex/beta-1.37-6/sources/beta-2019-07-23/gh/isaacazuelos/rs_gc_dead_end/Cargo.toml
[INFO] crate isaacazuelos/rs_gc_dead_end already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.36.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-07-23" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] testing isaacazuelos/rs_gc_dead_end against 1.36.0 for beta-1.37-6
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.37-6/worker-3/1.36.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.37-6/sources/1.36.0/gh/isaacazuelos/rs_gc_dead_end:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+1.36.0" "build" "--frozen"`
[INFO] [stdout] 6796c9a987cc49c336da2ae6d36006a98344783fa745bcb0d9b9c57effe8ce95
[INFO] running `"docker" "start" "-a" "6796c9a987cc49c336da2ae6d36006a98344783fa745bcb0d9b9c57effe8ce95"`
[INFO] [stderr]     Blocking waiting for file lock on package cache lock
[INFO] [stderr]    Compiling gc v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused variable: `a`
[INFO] [stderr]    --> src/main.rs:164:9
[INFO] [stderr]     |
[INFO] [stderr] 164 |     let a = heap.intern(Node::new("a"));
[INFO] [stderr]     |         ^ help: consider prefixing with an underscore: `_a`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `b`
[INFO] [stderr]    --> src/main.rs:165:9
[INFO] [stderr]     |
[INFO] [stderr] 165 |     let b = heap.intern(Node::new("b"));
[INFO] [stderr]     |         ^ help: consider prefixing with an underscore: `_b`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `root`
[INFO] [stderr]   --> src/main.rs:85:24
[INFO] [stderr]    |
[INFO] [stderr] 85 |     fn mark(&mut self, root: &mut Gc<T>) {
[INFO] [stderr]    |                        ^^^^ help: consider prefixing with an underscore: `_root`
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `collect`
[INFO] [stderr]   --> src/main.rs:80:5
[INFO] [stderr]    |
[INFO] [stderr] 80 |     fn collect(&mut self, root: &mut Gc<T>) {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(dead_code)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `mark`
[INFO] [stderr]   --> src/main.rs:85:5
[INFO] [stderr]    |
[INFO] [stderr] 85 |     fn mark(&mut self, root: &mut Gc<T>) {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `sweep`
[INFO] [stderr]   --> src/main.rs:89:5
[INFO] [stderr]    |
[INFO] [stderr] 89 |     unsafe fn sweep(&mut self) {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `push_edge`
[INFO] [stderr]    --> src/main.rs:152:5
[INFO] [stderr]     |
[INFO] [stderr] 152 |     fn push_edge(&'a mut self, edge: Gc<'a, Node<'a>>) {
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.38s
[INFO] running `"docker" "inspect" "6796c9a987cc49c336da2ae6d36006a98344783fa745bcb0d9b9c57effe8ce95"`
[INFO] running `"docker" "rm" "-f" "6796c9a987cc49c336da2ae6d36006a98344783fa745bcb0d9b9c57effe8ce95"`
[INFO] [stdout] 6796c9a987cc49c336da2ae6d36006a98344783fa745bcb0d9b9c57effe8ce95
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.37-6/worker-3/1.36.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.37-6/sources/1.36.0/gh/isaacazuelos/rs_gc_dead_end:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+1.36.0" "test" "--frozen" "--no-run"`
[INFO] [stdout] c49523919d4c48814cfb81094d20a7df838c79ab56308b5501f369c627b8637e
[INFO] running `"docker" "start" "-a" "c49523919d4c48814cfb81094d20a7df838c79ab56308b5501f369c627b8637e"`
[INFO] [stderr]    Compiling gc v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused variable: `a`
[INFO] [stderr]    --> src/main.rs:164:9
[INFO] [stderr]     |
[INFO] [stderr] 164 |     let a = heap.intern(Node::new("a"));
[INFO] [stderr]     |         ^ help: consider prefixing with an underscore: `_a`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `b`
[INFO] [stderr]    --> src/main.rs:165:9
[INFO] [stderr]     |
[INFO] [stderr] 165 |     let b = heap.intern(Node::new("b"));
[INFO] [stderr]     |         ^ help: consider prefixing with an underscore: `_b`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `root`
[INFO] [stderr]   --> src/main.rs:85:24
[INFO] [stderr]    |
[INFO] [stderr] 85 |     fn mark(&mut self, root: &mut Gc<T>) {
[INFO] [stderr]    |                        ^^^^ help: consider prefixing with an underscore: `_root`
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `collect`
[INFO] [stderr]   --> src/main.rs:80:5
[INFO] [stderr]    |
[INFO] [stderr] 80 |     fn collect(&mut self, root: &mut Gc<T>) {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(dead_code)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `mark`
[INFO] [stderr]   --> src/main.rs:85:5
[INFO] [stderr]    |
[INFO] [stderr] 85 |     fn mark(&mut self, root: &mut Gc<T>) {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `sweep`
[INFO] [stderr]   --> src/main.rs:89:5
[INFO] [stderr]    |
[INFO] [stderr] 89 |     unsafe fn sweep(&mut self) {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `push_edge`
[INFO] [stderr]    --> src/main.rs:152:5
[INFO] [stderr]     |
[INFO] [stderr] 152 |     fn push_edge(&'a mut self, edge: Gc<'a, Node<'a>>) {
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.33s
[INFO] running `"docker" "inspect" "c49523919d4c48814cfb81094d20a7df838c79ab56308b5501f369c627b8637e"`
[INFO] running `"docker" "rm" "-f" "c49523919d4c48814cfb81094d20a7df838c79ab56308b5501f369c627b8637e"`
[INFO] [stdout] c49523919d4c48814cfb81094d20a7df838c79ab56308b5501f369c627b8637e
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.37-6/worker-3/1.36.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.37-6/sources/1.36.0/gh/isaacazuelos/rs_gc_dead_end:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+1.36.0" "test" "--frozen"`
[INFO] [stdout] 6b6ba0dda79b8e7a4e18d2dd388a695be8f0197d4124dcde89eef5750c28c6e7
[INFO] running `"docker" "start" "-a" "6b6ba0dda79b8e7a4e18d2dd388a695be8f0197d4124dcde89eef5750c28c6e7"`
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.01s
[INFO] [stderr]      Running /opt/crater/target/debug/deps/gc-3f72115c29a9838a
[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
[INFO] [stdout] 
[INFO] running `"docker" "inspect" "6b6ba0dda79b8e7a4e18d2dd388a695be8f0197d4124dcde89eef5750c28c6e7"`
[INFO] running `"docker" "rm" "-f" "6b6ba0dda79b8e7a4e18d2dd388a695be8f0197d4124dcde89eef5750c28c6e7"`
[INFO] [stdout] 6b6ba0dda79b8e7a4e18d2dd388a695be8f0197d4124dcde89eef5750c28c6e7