[INFO] updating cached repository trafficland/counter
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/trafficland/counter
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/trafficland/counter" "work/ex/pr-57967/sources/master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54/gh/trafficland/counter"`
[INFO] [stderr] Cloning into 'work/ex/pr-57967/sources/master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54/gh/trafficland/counter'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/trafficland/counter" "work/ex/pr-57967/sources/try#7fea0229842e79db1159ea58ad9a653b288efee9/gh/trafficland/counter"`
[INFO] [stderr] Cloning into 'work/ex/pr-57967/sources/try#7fea0229842e79db1159ea58ad9a653b288efee9/gh/trafficland/counter'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 3f30d2583eba4922a72b3ec885c831a2cf558067
[INFO] sha for GitHub repo trafficland/counter: 3f30d2583eba4922a72b3ec885c831a2cf558067
[INFO] validating manifest of trafficland/counter on toolchain master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of trafficland/counter on toolchain try#7fea0229842e79db1159ea58ad9a653b288efee9
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+7fea0229842e79db1159ea58ad9a653b288efee9-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing trafficland/counter
[INFO] finished frobbing trafficland/counter
[INFO] frobbed toml for trafficland/counter written to work/ex/pr-57967/sources/master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54/gh/trafficland/counter/Cargo.toml
[INFO] started frobbing trafficland/counter
[INFO] finished frobbing trafficland/counter
[INFO] frobbed toml for trafficland/counter written to work/ex/pr-57967/sources/try#7fea0229842e79db1159ea58ad9a653b288efee9/gh/trafficland/counter/Cargo.toml
[INFO] crate trafficland/counter has a lockfile. skipping
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+7fea0229842e79db1159ea58ad9a653b288efee9-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] building trafficland/counter against master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54 for pr-57967
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-57967/worker-0/master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-57967/sources/master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54/gh/trafficland/counter:/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=forbid" "-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" "+c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54-alt" "build" "--frozen"`
[INFO] [stdout] 425c1a73546443e8b834daff2cd84ee92599183b2dc5575ec70591cd0f0c26b1
[INFO] running `"docker" "start" "-a" "425c1a73546443e8b834daff2cd84ee92599183b2dc5575ec70591cd0f0c26b1"`
[INFO] [stderr]    Compiling variance v0.1.3
[INFO] [stderr]    Compiling scopeguard v0.1.2
[INFO] [stderr]    Compiling vec_map v0.7.0
[INFO] [stderr]    Compiling memchr v0.1.11
[INFO] [stderr]    Compiling thread-id v3.0.0
[INFO] [stderr]    Compiling atty v0.2.2
[INFO] [stderr]    Compiling term_size v0.3.0
[INFO] [stderr]    Compiling thread-id v2.0.0
[INFO] [stderr]    Compiling chrono v0.2.25
[INFO] [stderr]    Compiling thread_local v0.3.3
[INFO] [stderr]    Compiling aho-corasick v0.5.3
[INFO] [stderr]    Compiling thread_local v0.2.7
[INFO] [stderr]    Compiling scoped-pool v1.0.0
[INFO] [stderr]    Compiling clap v2.23.3
[INFO] [stderr]    Compiling regex v0.2.1
[INFO] [stderr]    Compiling regex v0.1.80
[INFO] [stderr]    Compiling counter v1.0.0 (/opt/crater/workdir)
[INFO] [stderr]    Compiling elp v2.0.0
[INFO] [stderr]    Compiling env_logger v0.3.5
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/aggregation_control.rs:24:39
[INFO] [stderr]    |
[INFO] [stderr] 24 |     pub fn run_aggregation(&mut self, mut filenames: &mut Vec<PathBuf>) -> FileAggregation {
[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:96:52
[INFO] [stderr]    |
[INFO] [stderr] 96 |     fn run(&mut self, num_file_aggregators: usize, mut filenames: &mut Vec<PathBuf>) -> counter::FileAggregation {
[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]     Finished dev [unoptimized + debuginfo] target(s) in 45.68s
[INFO] running `"docker" "inspect" "425c1a73546443e8b834daff2cd84ee92599183b2dc5575ec70591cd0f0c26b1"`
[INFO] running `"docker" "rm" "-f" "425c1a73546443e8b834daff2cd84ee92599183b2dc5575ec70591cd0f0c26b1"`
[INFO] [stdout] 425c1a73546443e8b834daff2cd84ee92599183b2dc5575ec70591cd0f0c26b1
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-57967/worker-0/master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-57967/sources/master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54/gh/trafficland/counter:/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=forbid" "-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" "+c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54-alt" "test" "--frozen" "--no-run"`
[INFO] [stdout] 68a68ed9da5223e5a6e34eb1de52513de09e67c8616252d5cdd6313de32ae07e
[INFO] running `"docker" "start" "-a" "68a68ed9da5223e5a6e34eb1de52513de09e67c8616252d5cdd6313de32ae07e"`
[INFO] [stderr]    Compiling names v0.11.0
[INFO] [stderr]    Compiling rand v0.3.15
[INFO] [stderr]    Compiling counter v1.0.0 (/opt/crater/workdir)
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:96:52
[INFO] [stderr]    |
[INFO] [stderr] 96 |     fn run(&mut self, num_file_aggregators: usize, mut filenames: &mut Vec<PathBuf>) -> counter::FileAggregation {
[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/file_handling.rs:355:23
[INFO] [stderr]     |
[INFO] [stderr] 355 |                 .map(|mut g| g.next().unwrap())
[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/aggregation_control.rs:24:39
[INFO] [stderr]    |
[INFO] [stderr] 24 |     pub fn run_aggregation(&mut self, mut filenames: &mut Vec<PathBuf>) -> FileAggregation {
[INFO] [stderr]    |                                       ----^^^^^^^^^
[INFO] [stderr]    |                                       |
[INFO] [stderr]    |                                       help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 8.76s
[INFO] running `"docker" "inspect" "68a68ed9da5223e5a6e34eb1de52513de09e67c8616252d5cdd6313de32ae07e"`
[INFO] running `"docker" "rm" "-f" "68a68ed9da5223e5a6e34eb1de52513de09e67c8616252d5cdd6313de32ae07e"`
[INFO] [stdout] 68a68ed9da5223e5a6e34eb1de52513de09e67c8616252d5cdd6313de32ae07e