[INFO] updating cached repository modeverv/RustbookSec4_201906
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/modeverv/RustbookSec4_201906
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/modeverv/RustbookSec4_201906" "work/ex/pr-63565/sources/master#c43d03a19f326f4a323569328cc501e86eb6d22e/gh/modeverv/RustbookSec4_201906"`
[INFO] [stderr] Cloning into 'work/ex/pr-63565/sources/master#c43d03a19f326f4a323569328cc501e86eb6d22e/gh/modeverv/RustbookSec4_201906'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/modeverv/RustbookSec4_201906" "work/ex/pr-63565/sources/try#75eff020d0923c035c2fe220db4a0465cd847048/gh/modeverv/RustbookSec4_201906"`
[INFO] [stderr] Cloning into 'work/ex/pr-63565/sources/try#75eff020d0923c035c2fe220db4a0465cd847048/gh/modeverv/RustbookSec4_201906'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 4c4cf876a2d0a808d20003f16a818707ce9c1608
[INFO] sha for GitHub repo modeverv/RustbookSec4_201906: 4c4cf876a2d0a808d20003f16a818707ce9c1608
[INFO] validating manifest of modeverv/RustbookSec4_201906 on toolchain master#c43d03a19f326f4a323569328cc501e86eb6d22e
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+c43d03a19f326f4a323569328cc501e86eb6d22e-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of modeverv/RustbookSec4_201906 on toolchain try#75eff020d0923c035c2fe220db4a0465cd847048
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+75eff020d0923c035c2fe220db4a0465cd847048-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing modeverv/RustbookSec4_201906
[INFO] finished frobbing modeverv/RustbookSec4_201906
[INFO] frobbed toml for modeverv/RustbookSec4_201906 written to work/ex/pr-63565/sources/master#c43d03a19f326f4a323569328cc501e86eb6d22e/gh/modeverv/RustbookSec4_201906/Cargo.toml
[INFO] started frobbing modeverv/RustbookSec4_201906
[INFO] finished frobbing modeverv/RustbookSec4_201906
[INFO] frobbed toml for modeverv/RustbookSec4_201906 written to work/ex/pr-63565/sources/try#75eff020d0923c035c2fe220db4a0465cd847048/gh/modeverv/RustbookSec4_201906/Cargo.toml
[INFO] crate modeverv/RustbookSec4_201906 already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+c43d03a19f326f4a323569328cc501e86eb6d22e-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+75eff020d0923c035c2fe220db4a0465cd847048-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] checking modeverv/RustbookSec4_201906 against master#c43d03a19f326f4a323569328cc501e86eb6d22e for pr-63565
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-63565/worker-0/master#c43d03a19f326f4a323569328cc501e86eb6d22e:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-63565/sources/master#c43d03a19f326f4a323569328cc501e86eb6d22e/gh/modeverv/RustbookSec4_201906:/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" "+c43d03a19f326f4a323569328cc501e86eb6d22e-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] d95756632ca6a0d540f79338d8e2f732d27c158f25fcd718b16d88721fcf12a6
[INFO] running `"docker" "start" "-a" "d95756632ca6a0d540f79338d8e2f732d27c158f25fcd718b16d88721fcf12a6"`
[INFO] [stderr]     Checking sec4 v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused variable: `n`
[INFO] [stderr]  --> src/main.rs:3:9
[INFO] [stderr]   |
[INFO] [stderr] 3 |     let n = 42;
[INFO] [stderr]   |         ^ help: consider prefixing with an underscore: `_n`
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `c`
[INFO] [stderr]  --> src/main.rs:4:9
[INFO] [stderr]   |
[INFO] [stderr] 4 |     let c = 'R';
[INFO] [stderr]   |         ^ help: consider prefixing with an underscore: `_c`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `b2`
[INFO] [stderr]  --> src/main.rs:9:9
[INFO] [stderr]   |
[INFO] [stderr] 9 |     let b2 = !b1;
[INFO] [stderr]   |         ^^ help: consider prefixing with an underscore: `_b2`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `n1_ptr`
[INFO] [stderr]   --> src/main.rs:17:9
[INFO] [stderr]    |
[INFO] [stderr] 17 |     let n1_ptr = &n1;
[INFO] [stderr]    |         ^^^^^^ help: consider prefixing with an underscore: `_n1_ptr`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `n2_ptr_mut`
[INFO] [stderr]   --> src/main.rs:19:9
[INFO] [stderr]    |
[INFO] [stderr] 19 |     let n2_ptr_mut = &mut n2;
[INFO] [stderr]    |         ^^^^^^^^^^ help: consider prefixing with an underscore: `_n2_ptr_mut`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `n`
[INFO] [stderr]  --> src/main.rs:3:9
[INFO] [stderr]   |
[INFO] [stderr] 3 |     let n = 42;
[INFO] [stderr]   |         ^ help: consider prefixing with an underscore: `_n`
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `c`
[INFO] [stderr]  --> src/main.rs:4:9
[INFO] [stderr]   |
[INFO] [stderr] 4 |     let c = 'R';
[INFO] [stderr]   |         ^ help: consider prefixing with an underscore: `_c`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `b2`
[INFO] [stderr]  --> src/main.rs:9:9
[INFO] [stderr]   |
[INFO] [stderr] 9 |     let b2 = !b1;
[INFO] [stderr]   |         ^^ help: consider prefixing with an underscore: `_b2`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `n1_ptr`
[INFO] [stderr]   --> src/main.rs:17:9
[INFO] [stderr]    |
[INFO] [stderr] 17 |     let n1_ptr = &n1;
[INFO] [stderr]    |         ^^^^^^ help: consider prefixing with an underscore: `_n1_ptr`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `n2_ptr_mut`
[INFO] [stderr]   --> src/main.rs:19:9
[INFO] [stderr]    |
[INFO] [stderr] 19 |     let n2_ptr_mut = &mut n2;
[INFO] [stderr]    |         ^^^^^^^^^^ help: consider prefixing with an underscore: `_n2_ptr_mut`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:30:9
[INFO] [stderr]    |
[INFO] [stderr] 30 |     let mut o1 = Some(10);
[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: field is never used: `stroke_width`
[INFO] [stderr]   --> src/main.rs:51:5
[INFO] [stderr]    |
[INFO] [stderr] 51 |     stroke_width: u8,
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: field is never used: `fill`
[INFO] [stderr]   --> src/main.rs:52:5
[INFO] [stderr]    |
[INFO] [stderr] 52 |     fill: (u8,u8,u8)
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:30:9
[INFO] [stderr]    |
[INFO] [stderr] 30 |     let mut o1 = Some(10);
[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: field is never used: `stroke_width`
[INFO] [stderr]   --> src/main.rs:51:5
[INFO] [stderr]    |
[INFO] [stderr] 51 |     stroke_width: u8,
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: field is never used: `fill`
[INFO] [stderr]   --> src/main.rs:52:5
[INFO] [stderr]    |
[INFO] [stderr] 52 |     fill: (u8,u8,u8)
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.69s
[INFO] running `"docker" "inspect" "d95756632ca6a0d540f79338d8e2f732d27c158f25fcd718b16d88721fcf12a6"`
[INFO] running `"docker" "rm" "-f" "d95756632ca6a0d540f79338d8e2f732d27c158f25fcd718b16d88721fcf12a6"`
[INFO] [stdout] d95756632ca6a0d540f79338d8e2f732d27c158f25fcd718b16d88721fcf12a6