[INFO] updating cached repository Bkindmonk/RustPractice
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/Bkindmonk/RustPractice
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/Bkindmonk/RustPractice" "work/ex/pr-63565/sources/master#c43d03a19f326f4a323569328cc501e86eb6d22e/gh/Bkindmonk/RustPractice"`
[INFO] [stderr] Cloning into 'work/ex/pr-63565/sources/master#c43d03a19f326f4a323569328cc501e86eb6d22e/gh/Bkindmonk/RustPractice'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/Bkindmonk/RustPractice" "work/ex/pr-63565/sources/try#75eff020d0923c035c2fe220db4a0465cd847048/gh/Bkindmonk/RustPractice"`
[INFO] [stderr] Cloning into 'work/ex/pr-63565/sources/try#75eff020d0923c035c2fe220db4a0465cd847048/gh/Bkindmonk/RustPractice'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] dddc1c842ad316fb93f1f4a3a9741aea4ff490c9
[INFO] sha for GitHub repo Bkindmonk/RustPractice: dddc1c842ad316fb93f1f4a3a9741aea4ff490c9
[INFO] validating manifest of Bkindmonk/RustPractice 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 Bkindmonk/RustPractice 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 Bkindmonk/RustPractice
[INFO] finished frobbing Bkindmonk/RustPractice
[INFO] frobbed toml for Bkindmonk/RustPractice written to work/ex/pr-63565/sources/master#c43d03a19f326f4a323569328cc501e86eb6d22e/gh/Bkindmonk/RustPractice/Cargo.toml
[INFO] started frobbing Bkindmonk/RustPractice
[INFO] finished frobbing Bkindmonk/RustPractice
[INFO] frobbed toml for Bkindmonk/RustPractice written to work/ex/pr-63565/sources/try#75eff020d0923c035c2fe220db4a0465cd847048/gh/Bkindmonk/RustPractice/Cargo.toml
[INFO] crate Bkindmonk/RustPractice 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] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+75eff020d0923c035c2fe220db4a0465cd847048-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] checking Bkindmonk/RustPractice against master#c43d03a19f326f4a323569328cc501e86eb6d22e for pr-63565
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-63565/worker-1/master#c43d03a19f326f4a323569328cc501e86eb6d22e:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-63565/sources/master#c43d03a19f326f4a323569328cc501e86eb6d22e/gh/Bkindmonk/RustPractice:/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] 146e5d8dce639c03f753a29287831670e40d0e90c69190babf3c7d19c4db5c78
[INFO] running `"docker" "start" "-a" "146e5d8dce639c03f753a29287831670e40d0e90c69190babf3c7d19c4db5c78"`
[INFO] [stderr]     Checking mergesort v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:91:13
[INFO] [stderr]    |
[INFO] [stderr] 91 |         let mut realhalves = (*real).split_at_mut(halflength);
[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/main.rs:92:13
[INFO] [stderr]    |
[INFO] [stderr] 92 |         let mut scratchhalves = (*scratch).split_at_mut(halflength);
[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/main.rs:91:13
[INFO] [stderr]    |
[INFO] [stderr] 91 |         let mut realhalves = (*real).split_at_mut(halflength);
[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/main.rs:92:13
[INFO] [stderr]    |
[INFO] [stderr] 92 |         let mut scratchhalves = (*scratch).split_at_mut(halflength);
[INFO] [stderr]    |             ----^^^^^^^^^^^^^
[INFO] [stderr]    |             |
[INFO] [stderr]    |             help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.68s
[INFO] running `"docker" "inspect" "146e5d8dce639c03f753a29287831670e40d0e90c69190babf3c7d19c4db5c78"`
[INFO] running `"docker" "rm" "-f" "146e5d8dce639c03f753a29287831670e40d0e90c69190babf3c7d19c4db5c78"`
[INFO] [stdout] 146e5d8dce639c03f753a29287831670e40d0e90c69190babf3c7d19c4db5c78