[INFO] updating cached repository swizzard/boggler
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/swizzard/boggler
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/swizzard/boggler" "work/ex/pr-58592/sources/master#f66e4697ae286985ddefc53c3a047614568458bb/gh/swizzard/boggler"`
[INFO] [stderr] Cloning into 'work/ex/pr-58592/sources/master#f66e4697ae286985ddefc53c3a047614568458bb/gh/swizzard/boggler'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/swizzard/boggler" "work/ex/pr-58592/sources/try#c3b22200e6f5b70eb1f99ae6944d989ae17a458a/gh/swizzard/boggler"`
[INFO] [stderr] Cloning into 'work/ex/pr-58592/sources/try#c3b22200e6f5b70eb1f99ae6944d989ae17a458a/gh/swizzard/boggler'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] cc01442ec61024df5448d8460f06d2fcdd7e2531
[INFO] sha for GitHub repo swizzard/boggler: cc01442ec61024df5448d8460f06d2fcdd7e2531
[INFO] validating manifest of swizzard/boggler on toolchain master#f66e4697ae286985ddefc53c3a047614568458bb
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+f66e4697ae286985ddefc53c3a047614568458bb-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of swizzard/boggler on toolchain try#c3b22200e6f5b70eb1f99ae6944d989ae17a458a
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+c3b22200e6f5b70eb1f99ae6944d989ae17a458a-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing swizzard/boggler
[INFO] finished frobbing swizzard/boggler
[INFO] frobbed toml for swizzard/boggler written to work/ex/pr-58592/sources/master#f66e4697ae286985ddefc53c3a047614568458bb/gh/swizzard/boggler/Cargo.toml
[INFO] started frobbing swizzard/boggler
[INFO] finished frobbing swizzard/boggler
[INFO] frobbed toml for swizzard/boggler written to work/ex/pr-58592/sources/try#c3b22200e6f5b70eb1f99ae6944d989ae17a458a/gh/swizzard/boggler/Cargo.toml
[INFO] crate swizzard/boggler has a lockfile. skipping
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+f66e4697ae286985ddefc53c3a047614568458bb-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+c3b22200e6f5b70eb1f99ae6944d989ae17a458a-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] checking swizzard/boggler against try#c3b22200e6f5b70eb1f99ae6944d989ae17a458a for pr-58592
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-58592/worker-2/try#c3b22200e6f5b70eb1f99ae6944d989ae17a458a:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-58592/sources/try#c3b22200e6f5b70eb1f99ae6944d989ae17a458a/gh/swizzard/boggler:/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" "+c3b22200e6f5b70eb1f99ae6944d989ae17a458a-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] f9a1fffe12aee46b5bfa3591ea71c443f9c771d53fe2e257a13c66483b94d88f
[INFO] running `"docker" "start" "-a" "f9a1fffe12aee46b5bfa3591ea71c443f9c771d53fe2e257a13c66483b94d88f"`
[INFO] [stderr]     Checking boggler v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused variable: `seen`
[INFO] [stderr]    --> src/solver.rs:156:17
[INFO] [stderr]     |
[INFO] [stderr] 156 |         let mut seen: HashSet<BoardPosition> = HashSet::with_capacity(16);
[INFO] [stderr]     |                 ^^^^ help: consider prefixing with an underscore: `_seen`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `adjcts`
[INFO] [stderr]    --> src/solver.rs:158:17
[INFO] [stderr]     |
[INFO] [stderr] 158 |             let adjcts = board.adjacents(x, y);
[INFO] [stderr]     |                 ^^^^^^ help: consider prefixing with an underscore: `_adjcts`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/solver.rs:154:13
[INFO] [stderr]     |
[INFO] [stderr] 154 |         let mut x = 0;
[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/solver.rs:155:13
[INFO] [stderr]     |
[INFO] [stderr] 155 |         let mut y = 0;
[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/solver.rs:156:13
[INFO] [stderr]     |
[INFO] [stderr] 156 |         let mut seen: HashSet<BoardPosition> = HashSet::with_capacity(16);
[INFO] [stderr]     |             ----^^^^
[INFO] [stderr]     |             |
[INFO] [stderr]     |             help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `find_letter`
[INFO] [stderr]    --> src/solver.rs:149:5
[INFO] [stderr]     |
[INFO] [stderr] 149 |     fn find_letter(&self, chr: &AsciiChar) -> Option<&BTNode> {
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(dead_code)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `seen`
[INFO] [stderr]    --> src/solver.rs:156:17
[INFO] [stderr]     |
[INFO] [stderr] 156 |         let mut seen: HashSet<BoardPosition> = HashSet::with_capacity(16);
[INFO] [stderr]     |                 ^^^^ help: consider prefixing with an underscore: `_seen`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `adjcts`
[INFO] [stderr]    --> src/solver.rs:158:17
[INFO] [stderr]     |
[INFO] [stderr] 158 |             let adjcts = board.adjacents(x, y);
[INFO] [stderr]     |                 ^^^^^^ help: consider prefixing with an underscore: `_adjcts`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/solver.rs:154:13
[INFO] [stderr]     |
[INFO] [stderr] 154 |         let mut x = 0;
[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/solver.rs:155:13
[INFO] [stderr]     |
[INFO] [stderr] 155 |         let mut y = 0;
[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/solver.rs:156:13
[INFO] [stderr]     |
[INFO] [stderr] 156 |         let mut seen: HashSet<BoardPosition> = HashSet::with_capacity(16);
[INFO] [stderr]     |             ----^^^^
[INFO] [stderr]     |             |
[INFO] [stderr]     |             help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.51s
[INFO] running `"docker" "inspect" "f9a1fffe12aee46b5bfa3591ea71c443f9c771d53fe2e257a13c66483b94d88f"`
[INFO] running `"docker" "rm" "-f" "f9a1fffe12aee46b5bfa3591ea71c443f9c771d53fe2e257a13c66483b94d88f"`
[INFO] [stdout] f9a1fffe12aee46b5bfa3591ea71c443f9c771d53fe2e257a13c66483b94d88f