Dec 12 04:16:07.756 INFO checking 02alexander/maze-solver against try#aa9aa79c3c583aab59ac9134542d60a780c35e2e for pr-56677
Dec 12 04:16:07.756 INFO running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-56677/worker-6/try#aa9aa79c3c583aab59ac9134542d60a780c35e2e:/target:rw,Z" "-v" "/mnt/big/crater/work/local/test-source/worker-6/pr-56677/try#aa9aa79c3c583aab59ac9134542d60a780c35e2e:/source:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/source" "-e" "USER_ID=1000" "-e" "CMD=cargo +aa9aa79c3c583aab59ac9134542d60a780c35e2e-alt check --frozen --all --all-targets" "-e" "CARGO_TARGET_DIR=/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/cargo-home" "-e" "RUSTUP_HOME=/rustup-home" "-m" "1536M" "--network" "none" "crater"`
Dec 12 04:16:08.290 INFO [stdout] 399be8d0969c2d6131df08a5f295b910bfafa87756278f2408fb10c4e5e72256
Dec 12 04:16:08.292 INFO running `"docker" "start" "-a" "399be8d0969c2d6131df08a5f295b910bfafa87756278f2408fb10c4e5e72256"`
Dec 12 04:16:09.964 INFO [stderr] usermod: no changes
Dec 12 04:16:10.092 INFO [stderr]     Checking imagefmt v4.0.0
Dec 12 04:16:12.081 INFO [stderr]     Checking maze-solver v0.1.0 (/source)
Dec 12 04:16:12.988 INFO [stderr] warning: unused imports: `read`, `write`
Dec 12 04:16:12.988 INFO [stderr]  --> src/main.rs:3:16
Dec 12 04:16:12.988 INFO [stderr]   |
Dec 12 04:16:12.988 INFO [stderr] 3 | use imagefmt::{read, write, ColFmt, ColType};
Dec 12 04:16:12.988 INFO [stderr]   |                ^^^^  ^^^^^
Dec 12 04:16:12.988 INFO [stderr]   |
Dec 12 04:16:12.988 INFO [stderr]   = note: #[warn(unused_imports)] on by default
Dec 12 04:16:12.988 INFO [stderr] 
Dec 12 04:16:12.988 INFO [stderr] warning: unused import: `std::mem::drop`
Dec 12 04:16:12.988 INFO [stderr]  --> src/tree.rs:2:5
Dec 12 04:16:12.988 INFO [stderr]   |
Dec 12 04:16:12.988 INFO [stderr] 2 | use std::mem::drop;
Dec 12 04:16:12.988 INFO [stderr]   |     ^^^^^^^^^^^^^^
Dec 12 04:16:12.988 INFO [stderr] 
Dec 12 04:16:13.012 INFO [stderr] warning: unused import: `Node`
Dec 12 04:16:13.012 INFO [stderr]  --> src/path_to_end.rs:3:35
Dec 12 04:16:13.012 INFO [stderr]   |
Dec 12 04:16:13.012 INFO [stderr] 3 | use super::tree::{QuaternaryTree, Node, Link};
Dec 12 04:16:13.012 INFO [stderr]   |                                   ^^^^
Dec 12 04:16:13.012 INFO [stderr] 
Dec 12 04:16:13.188 INFO [stderr] warning: variable does not need to be mutable
Dec 12 04:16:13.188 INFO [stderr]   --> src/tree.rs:41:8
Dec 12 04:16:13.188 INFO [stderr]    |
Dec 12 04:16:13.188 INFO [stderr] 41 |             let mut cur = &mut *next.take().unwrap();
Dec 12 04:16:13.188 INFO [stderr]    |                 ----^^^
Dec 12 04:16:13.188 INFO [stderr]    |                 |
Dec 12 04:16:13.188 INFO [stderr]    |                 help: remove this `mut`
Dec 12 04:16:13.188 INFO [stderr]    |
Dec 12 04:16:13.188 INFO [stderr]    = note: #[warn(unused_mut)] on by default
Dec 12 04:16:13.188 INFO [stderr] 
Dec 12 04:16:13.214 INFO [stderr] warning: unused `std::result::Result` that must be used
Dec 12 04:16:13.214 INFO [stderr]   --> src/main.rs:20:2
Dec 12 04:16:13.214 INFO [stderr]    |
Dec 12 04:16:13.214 INFO [stderr] 20 |     imagefmt::write("out.bmp", maze.width, maze.height, ColFmt::RGB, &pixels, ColType::Auto);
Dec 12 04:16:13.214 INFO [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Dec 12 04:16:13.214 INFO [stderr]    |
Dec 12 04:16:13.214 INFO [stderr]    = note: #[warn(unused_must_use)] on by default
Dec 12 04:16:13.214 INFO [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
Dec 12 04:16:13.214 INFO [stderr] 
Dec 12 04:16:13.268 INFO [stderr] warning: unused imports: `read`, `write`
Dec 12 04:16:13.268 INFO [stderr]  --> src/main.rs:3:16
Dec 12 04:16:13.268 INFO [stderr]   |
Dec 12 04:16:13.268 INFO [stderr] 3 | use imagefmt::{read, write, ColFmt, ColType};
Dec 12 04:16:13.268 INFO [stderr]   |                ^^^^  ^^^^^
Dec 12 04:16:13.268 INFO [stderr]   |
Dec 12 04:16:13.268 INFO [stderr]   = note: #[warn(unused_imports)] on by default
Dec 12 04:16:13.268 INFO [stderr] 
Dec 12 04:16:13.268 INFO [stderr] warning: unused import: `std::mem::drop`
Dec 12 04:16:13.268 INFO [stderr]  --> src/tree.rs:2:5
Dec 12 04:16:13.268 INFO [stderr]   |
Dec 12 04:16:13.268 INFO [stderr] 2 | use std::mem::drop;
Dec 12 04:16:13.268 INFO [stderr]   |     ^^^^^^^^^^^^^^
Dec 12 04:16:13.268 INFO [stderr] 
Dec 12 04:16:13.480 INFO [stderr] warning: variable does not need to be mutable
Dec 12 04:16:13.480 INFO [stderr]   --> src/tree.rs:41:8
Dec 12 04:16:13.480 INFO [stderr]    |
Dec 12 04:16:13.480 INFO [stderr] 41 |             let mut cur = &mut *next.take().unwrap();
Dec 12 04:16:13.480 INFO [stderr]    |                 ----^^^
Dec 12 04:16:13.480 INFO [stderr]    |                 |
Dec 12 04:16:13.480 INFO [stderr]    |                 help: remove this `mut`
Dec 12 04:16:13.480 INFO [stderr]    |
Dec 12 04:16:13.480 INFO [stderr]    = note: #[warn(unused_mut)] on by default
Dec 12 04:16:13.480 INFO [stderr] 
Dec 12 04:16:13.545 INFO [stderr] warning: unused `std::result::Result` that must be used
Dec 12 04:16:13.545 INFO [stderr]   --> src/main.rs:20:2
Dec 12 04:16:13.545 INFO [stderr]    |
Dec 12 04:16:13.546 INFO [stderr] 20 |     imagefmt::write("out.bmp", maze.width, maze.height, ColFmt::RGB, &pixels, ColType::Auto);
Dec 12 04:16:13.546 INFO [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Dec 12 04:16:13.546 INFO [stderr]    |
Dec 12 04:16:13.546 INFO [stderr]    = note: #[warn(unused_must_use)] on by default
Dec 12 04:16:13.546 INFO [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
Dec 12 04:16:13.546 INFO [stderr] 
Dec 12 04:16:13.612 INFO [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 3.61s
Dec 12 04:16:13.615 INFO [stderr] su: No module specific data is present
Dec 12 04:16:14.713 INFO running `"docker" "inspect" "399be8d0969c2d6131df08a5f295b910bfafa87756278f2408fb10c4e5e72256"`
Dec 12 04:16:15.000 INFO running `"docker" "rm" "-f" "399be8d0969c2d6131df08a5f295b910bfafa87756278f2408fb10c4e5e72256"`
Dec 12 04:16:15.344 INFO [stdout] 399be8d0969c2d6131df08a5f295b910bfafa87756278f2408fb10c4e5e72256