[INFO] crate nn 0.1.6 is already in cache
[INFO] extracting crate nn 0.1.6 into work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/reg/nn/0.1.6
[INFO] extracting crate nn 0.1.6 into work/ex/pr-63376/sources/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7/reg/nn/0.1.6
[INFO] validating manifest of nn-0.1.6 on toolchain master#60960a260f7b5c695fd0717311d72ce62dd4eb43
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+60960a260f7b5c695fd0717311d72ce62dd4eb43-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of nn-0.1.6 on toolchain try#266783e4e09e4e9d5307c1c8e695659c58bbcac7
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+266783e4e09e4e9d5307c1c8e695659c58bbcac7-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing nn-0.1.6
[INFO] finished frobbing nn-0.1.6
[INFO] frobbed toml for nn-0.1.6 written to work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/reg/nn/0.1.6/Cargo.toml
[INFO] started frobbing nn-0.1.6
[INFO] finished frobbing nn-0.1.6
[INFO] frobbed toml for nn-0.1.6 written to work/ex/pr-63376/sources/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7/reg/nn/0.1.6/Cargo.toml
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+60960a260f7b5c695fd0717311d72ce62dd4eb43-alt" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+266783e4e09e4e9d5307c1c8e695659c58bbcac7-alt" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+60960a260f7b5c695fd0717311d72ce62dd4eb43-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+266783e4e09e4e9d5307c1c8e695659c58bbcac7-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] checking nn-0.1.6 against try#266783e4e09e4e9d5307c1c8e695659c58bbcac7 for pr-63376
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-63376/worker-1/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-63376/sources/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7/reg/nn/0.1.6:/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" "+266783e4e09e4e9d5307c1c8e695659c58bbcac7-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] 5c7985bb99fdbf0758412b7a2ba1d0114308d13a17358685d89a5f941b2f1fa6
[INFO] running `"docker" "start" "-a" "5c7985bb99fdbf0758412b7a2ba1d0114308d13a17358685d89a5f941b2f1fa6"`
[INFO] [stderr]     Checking rustc-serialize v0.3.24
[INFO] [stderr]     Checking rand v0.4.6
[INFO] [stderr]     Checking time v0.1.42
[INFO] [stderr]     Checking rand v0.3.23
[INFO] [stderr]     Checking nn v0.1.6 (/opt/crater/workdir)
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/lib.rs:361:17
[INFO] [stderr]     |
[INFO] [stderr] 361 |             let mut layer = &mut self.layers[layer_index];
[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:364:21
[INFO] [stderr]     |
[INFO] [stderr] 364 |                 let mut node = &mut layer[node_index];
[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/lib.rs:394:21
[INFO] [stderr]     |
[INFO] [stderr] 394 |                 let mut node_error;
[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/lib.rs:410:25
[INFO] [stderr]     |
[INFO] [stderr] 410 |                     let mut prev_layer_result;
[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/lib.rs:361:17
[INFO] [stderr]     |
[INFO] [stderr] 361 |             let mut layer = &mut self.layers[layer_index];
[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:364:21
[INFO] [stderr]     |
[INFO] [stderr] 364 |                 let mut node = &mut layer[node_index];
[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/lib.rs:394:21
[INFO] [stderr]     |
[INFO] [stderr] 394 |                 let mut node_error;
[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/lib.rs:410:25
[INFO] [stderr]     |
[INFO] [stderr] 410 |                     let mut prev_layer_result;
[INFO] [stderr]     |                         ----^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |                         |
[INFO] [stderr]     |                         help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 7.28s
[INFO] running `"docker" "inspect" "5c7985bb99fdbf0758412b7a2ba1d0114308d13a17358685d89a5f941b2f1fa6"`
[INFO] running `"docker" "rm" "-f" "5c7985bb99fdbf0758412b7a2ba1d0114308d13a17358685d89a5f941b2f1fa6"`
[INFO] [stdout] 5c7985bb99fdbf0758412b7a2ba1d0114308d13a17358685d89a5f941b2f1fa6