[INFO] updating cached repository syntheticsh/binary-play
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/syntheticsh/binary-play
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/syntheticsh/binary-play" "work/ex/beta-1.37-6/sources/1.36.0/gh/syntheticsh/binary-play"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.37-6/sources/1.36.0/gh/syntheticsh/binary-play'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/syntheticsh/binary-play" "work/ex/beta-1.37-6/sources/beta-2019-07-23/gh/syntheticsh/binary-play"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.37-6/sources/beta-2019-07-23/gh/syntheticsh/binary-play'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 2ef5ff608528a7ce2e4a22f44bd1871aab525fd7
[INFO] sha for GitHub repo syntheticsh/binary-play: 2ef5ff608528a7ce2e4a22f44bd1871aab525fd7
[INFO] validating manifest of syntheticsh/binary-play 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 syntheticsh/binary-play 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 syntheticsh/binary-play
[INFO] finished frobbing syntheticsh/binary-play
[INFO] frobbed toml for syntheticsh/binary-play written to work/ex/beta-1.37-6/sources/1.36.0/gh/syntheticsh/binary-play/Cargo.toml
[INFO] started frobbing syntheticsh/binary-play
[INFO] finished frobbing syntheticsh/binary-play
[INFO] frobbed toml for syntheticsh/binary-play written to work/ex/beta-1.37-6/sources/beta-2019-07-23/gh/syntheticsh/binary-play/Cargo.toml
[INFO] crate syntheticsh/binary-play 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 syntheticsh/binary-play 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-6/1.36.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.37-6/sources/1.36.0/gh/syntheticsh/binary-play:/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] 37a4688dbd257b8162f8606a0795dcc4a0d6f328f34e09e2901f29ab4826fc10
[INFO] running `"docker" "start" "-a" "37a4688dbd257b8162f8606a0795dcc4a0d6f328f34e09e2901f29ab4826fc10"`
[INFO] [stderr]    Compiling binary v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/lib.rs:222:26
[INFO] [stderr]     |
[INFO] [stderr] 222 |                     let (mut detached_head, mut right) = head_tree.take_right();
[INFO] [stderr]     |                          ----^^^^^^^^^^^^^
[INFO] [stderr]     |                          |
[INFO] [stderr]     |                          help: remove this `mut`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unused_mut)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/lib.rs:222:45
[INFO] [stderr]     |
[INFO] [stderr] 222 |                     let (mut detached_head, mut right) = head_tree.take_right();
[INFO] [stderr]     |                                             ----^^^^^
[INFO] [stderr]     |                                             |
[INFO] [stderr]     |                                             help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:41:13
[INFO] [stderr]    |
[INFO] [stderr] 41 |         let mut left = branch.as_mut();
[INFO] [stderr]    |             ----^^^^
[INFO] [stderr]    |             |
[INFO] [stderr]    |             help: remove this `mut`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_mut)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:46:13
[INFO] [stderr]    |
[INFO] [stderr] 46 |         let mut right = branch.as_mut();
[INFO] [stderr]    |             ----^^^^^
[INFO] [stderr]    |             |
[INFO] [stderr]    |             help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.19s
[INFO] running `"docker" "inspect" "37a4688dbd257b8162f8606a0795dcc4a0d6f328f34e09e2901f29ab4826fc10"`
[INFO] running `"docker" "rm" "-f" "37a4688dbd257b8162f8606a0795dcc4a0d6f328f34e09e2901f29ab4826fc10"`
[INFO] [stdout] 37a4688dbd257b8162f8606a0795dcc4a0d6f328f34e09e2901f29ab4826fc10
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.37-6/worker-6/1.36.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.37-6/sources/1.36.0/gh/syntheticsh/binary-play:/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] 100ebd72aa40cfce5090d147da49ad32e6399045754d49d2f28e8dfcb2952d03
[INFO] running `"docker" "start" "-a" "100ebd72aa40cfce5090d147da49ad32e6399045754d49d2f28e8dfcb2952d03"`
[INFO] [stderr]    Compiling binary v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/lib.rs:222:26
[INFO] [stderr]     |
[INFO] [stderr] 222 |                     let (mut detached_head, mut right) = head_tree.take_right();
[INFO] [stderr]     |                          ----^^^^^^^^^^^^^
[INFO] [stderr]     |                          |
[INFO] [stderr]     |                          help: remove this `mut`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unused_mut)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/lib.rs:222:45
[INFO] [stderr]     |
[INFO] [stderr] 222 |                     let (mut detached_head, mut right) = head_tree.take_right();
[INFO] [stderr]     |                                             ----^^^^^
[INFO] [stderr]     |                                             |
[INFO] [stderr]     |                                             help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:41:13
[INFO] [stderr]    |
[INFO] [stderr] 41 |         let mut left = branch.as_mut();
[INFO] [stderr]    |             ----^^^^
[INFO] [stderr]    |             |
[INFO] [stderr]    |             help: remove this `mut`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_mut)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:46:13
[INFO] [stderr]    |
[INFO] [stderr] 46 |         let mut right = branch.as_mut();
[INFO] [stderr]    |             ----^^^^^
[INFO] [stderr]    |             |
[INFO] [stderr]    |             help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.67s
[INFO] running `"docker" "inspect" "100ebd72aa40cfce5090d147da49ad32e6399045754d49d2f28e8dfcb2952d03"`
[INFO] running `"docker" "rm" "-f" "100ebd72aa40cfce5090d147da49ad32e6399045754d49d2f28e8dfcb2952d03"`
[INFO] [stdout] 100ebd72aa40cfce5090d147da49ad32e6399045754d49d2f28e8dfcb2952d03
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.37-6/worker-6/1.36.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.37-6/sources/1.36.0/gh/syntheticsh/binary-play:/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] d0245b908b986b1371bf48704684e3b2caa130fa9d1eecaef376a92975e5d1a4
[INFO] running `"docker" "start" "-a" "d0245b908b986b1371bf48704684e3b2caa130fa9d1eecaef376a92975e5d1a4"`
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.01s
[INFO] [stderr]      Running /opt/crater/target/debug/deps/binary-73a93ab8f2a58f22
[INFO] [stderr]      Running /opt/crater/target/debug/deps/binary-6e2c57656f73af00
[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] [stdout] 
[INFO] [stderr]    Doc-tests binary
[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] [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" "d0245b908b986b1371bf48704684e3b2caa130fa9d1eecaef376a92975e5d1a4"`
[INFO] running `"docker" "rm" "-f" "d0245b908b986b1371bf48704684e3b2caa130fa9d1eecaef376a92975e5d1a4"`
[INFO] [stdout] d0245b908b986b1371bf48704684e3b2caa130fa9d1eecaef376a92975e5d1a4