[INFO] updating cached repository CloneRob/iron_woods
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/CloneRob/iron_woods
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/CloneRob/iron_woods" "work/ex/beta-1.38-1/sources/1.37.0/gh/CloneRob/iron_woods"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/CloneRob/iron_woods'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/CloneRob/iron_woods" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/CloneRob/iron_woods"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/CloneRob/iron_woods'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] d892a15c6b4292bb45efb6a830c8b6afd5fe4ea3
[INFO] sha for GitHub repo CloneRob/iron_woods: d892a15c6b4292bb45efb6a830c8b6afd5fe4ea3
[INFO] validating manifest of CloneRob/iron_woods on toolchain 1.37.0
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of CloneRob/iron_woods on toolchain beta-2019-08-13
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing CloneRob/iron_woods
[INFO] finished frobbing CloneRob/iron_woods
[INFO] frobbed toml for CloneRob/iron_woods written to work/ex/beta-1.38-1/sources/1.37.0/gh/CloneRob/iron_woods/Cargo.toml
[INFO] started frobbing CloneRob/iron_woods
[INFO] finished frobbing CloneRob/iron_woods
[INFO] frobbed toml for CloneRob/iron_woods written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/CloneRob/iron_woods/Cargo.toml
[INFO] crate CloneRob/iron_woods already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] testing CloneRob/iron_woods against 1.37.0 for beta-1.38-1
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-1/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/CloneRob/iron_woods:/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" "+1.37.0" "build" "--frozen"`
[INFO] [stdout] 4d4f446567450a52f4bf21e7a59c023ce45d6efa3f7ff8a33701b2acdce8452f
[INFO] running `"docker" "start" "-a" "4d4f446567450a52f4bf21e7a59c023ce45d6efa3f7ff8a33701b2acdce8452f"`
[INFO] [stderr]    Compiling iron_woods v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused import: `std::collections::HashMap`
[INFO] [stderr]  --> src/main.rs:1:5
[INFO] [stderr]   |
[INFO] [stderr] 1 | use std::collections::HashMap;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: #[warn(unused_imports)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::cmp`
[INFO] [stderr]  --> src/feature/mod.rs:1:5
[INFO] [stderr]   |
[INFO] [stderr] 1 | use std::cmp;
[INFO] [stderr]   |     ^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `Hash`
[INFO] [stderr]  --> src/feature/mod.rs:3:17
[INFO] [stderr]   |
[INFO] [stderr] 3 | use std::hash::{Hash, Hasher};
[INFO] [stderr]   |                 ^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::iter::FromIterator`
[INFO] [stderr]  --> src/feature/mod.rs:4:5
[INFO] [stderr]   |
[INFO] [stderr] 4 | use std::iter::FromIterator;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused imports: `Index`, `RangeFrom`, `RangeTo`
[INFO] [stderr]  --> src/feature/mod.rs:5:16
[INFO] [stderr]   |
[INFO] [stderr] 5 | use std::ops::{Index, RangeTo, RangeFrom};
[INFO] [stderr]   |                ^^^^^  ^^^^^^^  ^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `HashSet`
[INFO] [stderr]  --> src/feature/mod.rs:6:24
[INFO] [stderr]   |
[INFO] [stderr] 6 | use std::collections::{HashSet, HashMap};
[INFO] [stderr]   |                        ^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `Hasher`
[INFO] [stderr]  --> src/feature/mod.rs:3:23
[INFO] [stderr]   |
[INFO] [stderr] 3 | use std::hash::{Hash, Hasher};
[INFO] [stderr]   |                       ^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `value_index`
[INFO] [stderr]   --> src/decision_tree/mod.rs:33:18
[INFO] [stderr]    |
[INFO] [stderr] 33 |             for (value_index, value) in feature.iter().enumerate() {
[INFO] [stderr]    |                  ^^^^^^^^^^^ help: consider prefixing with an underscore: `_value_index`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `depth`
[INFO] [stderr]   --> src/decision_tree/mod.rs:30:49
[INFO] [stderr]    |
[INFO] [stderr] 30 |     fn build_tree(&mut self, dataset: &Dataset, depth: usize) -> DecisionTree {
[INFO] [stderr]    |                                                 ^^^^^ help: consider prefixing with an underscore: `_depth`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `data`
[INFO] [stderr]   --> src/decision_tree/mod.rs:51:34
[INFO] [stderr]    |
[INFO] [stderr] 51 |     fn argmin_cost<D: Splitable>(data: D) -> (f32, usize, Value) {
[INFO] [stderr]    |                                  ^^^^ help: consider prefixing with an underscore: `_data`
[INFO] [stderr] 
[INFO] [stderr] warning: field is never used: `root`
[INFO] [stderr]  --> src/decision_tree/mod.rs:7:5
[INFO] [stderr]   |
[INFO] [stderr] 7 |     root: Option<DecisionNode>,
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: #[warn(dead_code)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: field is never used: `min_split`
[INFO] [stderr]  --> src/decision_tree/mod.rs:8:5
[INFO] [stderr]   |
[INFO] [stderr] 8 |     min_split: usize,
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never used: `min_impurity`
[INFO] [stderr]  --> src/decision_tree/mod.rs:9:5
[INFO] [stderr]   |
[INFO] [stderr] 9 |     min_impurity: f32,
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never used: `max_depth`
[INFO] [stderr]   --> src/decision_tree/mod.rs:10:5
[INFO] [stderr]    |
[INFO] [stderr] 10 |     max_depth: usize,
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never used: `cost_fn`
[INFO] [stderr]   --> src/decision_tree/mod.rs:11:5
[INFO] [stderr]    |
[INFO] [stderr] 11 |     cost_fn: fn(&[f32]) -> f32,
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never used: `leaf_fn`
[INFO] [stderr]   --> src/decision_tree/mod.rs:12:5
[INFO] [stderr]    |
[INFO] [stderr] 12 |     leaf_fn: fn() -> f32,
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `build_tree`
[INFO] [stderr]   --> src/decision_tree/mod.rs:30:5
[INFO] [stderr]    |
[INFO] [stderr] 30 |     fn build_tree(&mut self, dataset: &Dataset, depth: usize) -> DecisionTree {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `argmin_cost`
[INFO] [stderr]   --> src/decision_tree/mod.rs:51:5
[INFO] [stderr]    |
[INFO] [stderr] 51 |     fn argmin_cost<D: Splitable>(data: D) -> (f32, usize, Value) {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.98s
[INFO] running `"docker" "inspect" "4d4f446567450a52f4bf21e7a59c023ce45d6efa3f7ff8a33701b2acdce8452f"`
[INFO] running `"docker" "rm" "-f" "4d4f446567450a52f4bf21e7a59c023ce45d6efa3f7ff8a33701b2acdce8452f"`
[INFO] [stdout] 4d4f446567450a52f4bf21e7a59c023ce45d6efa3f7ff8a33701b2acdce8452f
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-1/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/CloneRob/iron_woods:/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" "+1.37.0" "test" "--frozen" "--no-run"`
[INFO] [stdout] 15b253ff25c7a30f3d50c1e76a1bc37e4718dbc5c36113e262d8e10b21249e95
[INFO] running `"docker" "start" "-a" "15b253ff25c7a30f3d50c1e76a1bc37e4718dbc5c36113e262d8e10b21249e95"`
[INFO] [stderr]    Compiling iron_woods v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused import: `std::collections::HashMap`
[INFO] [stderr]  --> src/main.rs:1:5
[INFO] [stderr]   |
[INFO] [stderr] 1 | use std::collections::HashMap;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: #[warn(unused_imports)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::cmp`
[INFO] [stderr]  --> src/feature/mod.rs:1:5
[INFO] [stderr]   |
[INFO] [stderr] 1 | use std::cmp;
[INFO] [stderr]   |     ^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `Hash`
[INFO] [stderr]  --> src/feature/mod.rs:3:17
[INFO] [stderr]   |
[INFO] [stderr] 3 | use std::hash::{Hash, Hasher};
[INFO] [stderr]   |                 ^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::iter::FromIterator`
[INFO] [stderr]  --> src/feature/mod.rs:4:5
[INFO] [stderr]   |
[INFO] [stderr] 4 | use std::iter::FromIterator;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused imports: `Index`, `RangeFrom`, `RangeTo`
[INFO] [stderr]  --> src/feature/mod.rs:5:16
[INFO] [stderr]   |
[INFO] [stderr] 5 | use std::ops::{Index, RangeTo, RangeFrom};
[INFO] [stderr]   |                ^^^^^  ^^^^^^^  ^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `HashSet`
[INFO] [stderr]  --> src/feature/mod.rs:6:24
[INFO] [stderr]   |
[INFO] [stderr] 6 | use std::collections::{HashSet, HashMap};
[INFO] [stderr]   |                        ^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `Hasher`
[INFO] [stderr]  --> src/feature/mod.rs:3:23
[INFO] [stderr]   |
[INFO] [stderr] 3 | use std::hash::{Hash, Hasher};
[INFO] [stderr]   |                       ^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `value_index`
[INFO] [stderr]   --> src/decision_tree/mod.rs:33:18
[INFO] [stderr]    |
[INFO] [stderr] 33 |             for (value_index, value) in feature.iter().enumerate() {
[INFO] [stderr]    |                  ^^^^^^^^^^^ help: consider prefixing with an underscore: `_value_index`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `depth`
[INFO] [stderr]   --> src/decision_tree/mod.rs:30:49
[INFO] [stderr]    |
[INFO] [stderr] 30 |     fn build_tree(&mut self, dataset: &Dataset, depth: usize) -> DecisionTree {
[INFO] [stderr]    |                                                 ^^^^^ help: consider prefixing with an underscore: `_depth`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `data`
[INFO] [stderr]   --> src/decision_tree/mod.rs:51:34
[INFO] [stderr]    |
[INFO] [stderr] 51 |     fn argmin_cost<D: Splitable>(data: D) -> (f32, usize, Value) {
[INFO] [stderr]    |                                  ^^^^ help: consider prefixing with an underscore: `_data`
[INFO] [stderr] 
[INFO] [stderr] warning: field is never used: `root`
[INFO] [stderr]  --> src/decision_tree/mod.rs:7:5
[INFO] [stderr]   |
[INFO] [stderr] 7 |     root: Option<DecisionNode>,
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: #[warn(dead_code)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: field is never used: `min_split`
[INFO] [stderr]  --> src/decision_tree/mod.rs:8:5
[INFO] [stderr]   |
[INFO] [stderr] 8 |     min_split: usize,
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never used: `min_impurity`
[INFO] [stderr]  --> src/decision_tree/mod.rs:9:5
[INFO] [stderr]   |
[INFO] [stderr] 9 |     min_impurity: f32,
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never used: `max_depth`
[INFO] [stderr]   --> src/decision_tree/mod.rs:10:5
[INFO] [stderr]    |
[INFO] [stderr] 10 |     max_depth: usize,
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never used: `cost_fn`
[INFO] [stderr]   --> src/decision_tree/mod.rs:11:5
[INFO] [stderr]    |
[INFO] [stderr] 11 |     cost_fn: fn(&[f32]) -> f32,
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never used: `leaf_fn`
[INFO] [stderr]   --> src/decision_tree/mod.rs:12:5
[INFO] [stderr]    |
[INFO] [stderr] 12 |     leaf_fn: fn() -> f32,
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `build_tree`
[INFO] [stderr]   --> src/decision_tree/mod.rs:30:5
[INFO] [stderr]    |
[INFO] [stderr] 30 |     fn build_tree(&mut self, dataset: &Dataset, depth: usize) -> DecisionTree {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `argmin_cost`
[INFO] [stderr]   --> src/decision_tree/mod.rs:51:5
[INFO] [stderr]    |
[INFO] [stderr] 51 |     fn argmin_cost<D: Splitable>(data: D) -> (f32, usize, Value) {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.77s
[INFO] running `"docker" "inspect" "15b253ff25c7a30f3d50c1e76a1bc37e4718dbc5c36113e262d8e10b21249e95"`
[INFO] running `"docker" "rm" "-f" "15b253ff25c7a30f3d50c1e76a1bc37e4718dbc5c36113e262d8e10b21249e95"`
[INFO] [stdout] 15b253ff25c7a30f3d50c1e76a1bc37e4718dbc5c36113e262d8e10b21249e95
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-1/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/CloneRob/iron_woods:/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" "+1.37.0" "test" "--frozen"`
[INFO] [stdout] fdb790bc22a905f93d513ac0679ec9fe538de8f580b5824e23d29aae6e29198e
[INFO] running `"docker" "start" "-a" "fdb790bc22a905f93d513ac0679ec9fe538de8f580b5824e23d29aae6e29198e"`
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.03s
[INFO] [stderr]      Running /opt/crater/target/debug/deps/iron_woods-9fa62701a83af889
[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" "fdb790bc22a905f93d513ac0679ec9fe538de8f580b5824e23d29aae6e29198e"`
[INFO] running `"docker" "rm" "-f" "fdb790bc22a905f93d513ac0679ec9fe538de8f580b5824e23d29aae6e29198e"`
[INFO] [stdout] fdb790bc22a905f93d513ac0679ec9fe538de8f580b5824e23d29aae6e29198e