[INFO] updating cached repository ethowitz/life
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/ethowitz/life
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/ethowitz/life" "work/ex/pr-63247/sources/master#452087b4bf18cece2d52d7cd8c9147195e5404bf/gh/ethowitz/life"`
[INFO] [stderr] Cloning into 'work/ex/pr-63247/sources/master#452087b4bf18cece2d52d7cd8c9147195e5404bf/gh/ethowitz/life'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/ethowitz/life" "work/ex/pr-63247/sources/try#757dacae0a9f1b46b3ab58a1f1232332e8fc7dab/gh/ethowitz/life"`
[INFO] [stderr] Cloning into 'work/ex/pr-63247/sources/try#757dacae0a9f1b46b3ab58a1f1232332e8fc7dab/gh/ethowitz/life'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] ed6ce81d54be37f00fcdb639475c3cdcd1c1c598
[INFO] sha for GitHub repo ethowitz/life: ed6ce81d54be37f00fcdb639475c3cdcd1c1c598
[INFO] validating manifest of ethowitz/life on toolchain master#452087b4bf18cece2d52d7cd8c9147195e5404bf
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+452087b4bf18cece2d52d7cd8c9147195e5404bf-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of ethowitz/life on toolchain try#757dacae0a9f1b46b3ab58a1f1232332e8fc7dab
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+757dacae0a9f1b46b3ab58a1f1232332e8fc7dab-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing ethowitz/life
[INFO] finished frobbing ethowitz/life
[INFO] frobbed toml for ethowitz/life written to work/ex/pr-63247/sources/master#452087b4bf18cece2d52d7cd8c9147195e5404bf/gh/ethowitz/life/Cargo.toml
[INFO] started frobbing ethowitz/life
[INFO] finished frobbing ethowitz/life
[INFO] frobbed toml for ethowitz/life written to work/ex/pr-63247/sources/try#757dacae0a9f1b46b3ab58a1f1232332e8fc7dab/gh/ethowitz/life/Cargo.toml
[INFO] crate ethowitz/life already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+452087b4bf18cece2d52d7cd8c9147195e5404bf-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+757dacae0a9f1b46b3ab58a1f1232332e8fc7dab-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] checking ethowitz/life against try#757dacae0a9f1b46b3ab58a1f1232332e8fc7dab for pr-63247
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-63247/worker-3/try#757dacae0a9f1b46b3ab58a1f1232332e8fc7dab:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-63247/sources/try#757dacae0a9f1b46b3ab58a1f1232332e8fc7dab/gh/ethowitz/life:/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" "+757dacae0a9f1b46b3ab58a1f1232332e8fc7dab-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] ab986f03cd959332d052bc0aaab3609f646fa9816496ac00d7bf2dc0a0ea043d
[INFO] running `"docker" "start" "-a" "ab986f03cd959332d052bc0aaab3609f646fa9816496ac00d7bf2dc0a0ea043d"`
[INFO] [stderr]     Checking life v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused variable: `x`
[INFO] [stderr]   --> src/main.rs:55:21
[INFO] [stderr]    |
[INFO] [stderr] 55 |     let gen_char = |x| if rand::random::<i64>() % 4 == 1 {ALIVE} else {' '};
[INFO] [stderr]    |                     ^ help: consider prefixing with an underscore: `_x`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning[E0506]: cannot assign to `*row` because it is borrowed
[INFO] [stderr]   --> src/main.rs:57:9
[INFO] [stderr]    |
[INFO] [stderr] 57 |         *row = row.into_iter().map(&gen_char).collect();
[INFO] [stderr]    |         ^^^^   ---                 --------- borrow later used here
[INFO] [stderr]    |         |      |
[INFO] [stderr]    |         |      borrow of `*row` occurs here
[INFO] [stderr]    |         assignment to borrowed `*row` occurs here
[INFO] [stderr]    |
[INFO] [stderr]    = warning: this error has been downgraded to a warning for backwards compatibility with previous releases
[INFO] [stderr]    = warning: this represents potential undefined behavior in your code and this warning will become a hard error in the future
[INFO] [stderr]    = note: for more information, try `rustc --explain E0729`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `x`
[INFO] [stderr]   --> src/main.rs:55:21
[INFO] [stderr]    |
[INFO] [stderr] 55 |     let gen_char = |x| if rand::random::<i64>() % 4 == 1 {ALIVE} else {' '};
[INFO] [stderr]    |                     ^ help: consider prefixing with an underscore: `_x`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning[E0506]: cannot assign to `*row` because it is borrowed
[INFO] [stderr]   --> src/main.rs:57:9
[INFO] [stderr]    |
[INFO] [stderr] 57 |         *row = row.into_iter().map(&gen_char).collect();
[INFO] [stderr]    |         ^^^^   ---                 --------- borrow later used here
[INFO] [stderr]    |         |      |
[INFO] [stderr]    |         |      borrow of `*row` occurs here
[INFO] [stderr]    |         assignment to borrowed `*row` occurs here
[INFO] [stderr]    |
[INFO] [stderr]    = warning: this error has been downgraded to a warning for backwards compatibility with previous releases
[INFO] [stderr]    = warning: this represents potential undefined behavior in your code and this warning will become a hard error in the future
[INFO] [stderr]    = note: for more information, try `rustc --explain E0729`
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.83s
[INFO] running `"docker" "inspect" "ab986f03cd959332d052bc0aaab3609f646fa9816496ac00d7bf2dc0a0ea043d"`
[INFO] running `"docker" "rm" "-f" "ab986f03cd959332d052bc0aaab3609f646fa9816496ac00d7bf2dc0a0ea043d"`
[INFO] [stdout] ab986f03cd959332d052bc0aaab3609f646fa9816496ac00d7bf2dc0a0ea043d