[INFO] updating cached repository vti/rust-test
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/vti/rust-test
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/vti/rust-test" "work/ex/pr-58592/sources/master#f66e4697ae286985ddefc53c3a047614568458bb/gh/vti/rust-test"`
[INFO] [stderr] Cloning into 'work/ex/pr-58592/sources/master#f66e4697ae286985ddefc53c3a047614568458bb/gh/vti/rust-test'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/vti/rust-test" "work/ex/pr-58592/sources/try#c3b22200e6f5b70eb1f99ae6944d989ae17a458a/gh/vti/rust-test"`
[INFO] [stderr] Cloning into 'work/ex/pr-58592/sources/try#c3b22200e6f5b70eb1f99ae6944d989ae17a458a/gh/vti/rust-test'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] d7117384986969a063cdc48940d257f2139d57a3
[INFO] sha for GitHub repo vti/rust-test: d7117384986969a063cdc48940d257f2139d57a3
[INFO] validating manifest of vti/rust-test 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 vti/rust-test 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 vti/rust-test
[INFO] finished frobbing vti/rust-test
[INFO] frobbed toml for vti/rust-test written to work/ex/pr-58592/sources/master#f66e4697ae286985ddefc53c3a047614568458bb/gh/vti/rust-test/Cargo.toml
[INFO] started frobbing vti/rust-test
[INFO] finished frobbing vti/rust-test
[INFO] frobbed toml for vti/rust-test written to work/ex/pr-58592/sources/try#c3b22200e6f5b70eb1f99ae6944d989ae17a458a/gh/vti/rust-test/Cargo.toml
[INFO] crate vti/rust-test 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 vti/rust-test against master#f66e4697ae286985ddefc53c3a047614568458bb for pr-58592
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-58592/worker-2/master#f66e4697ae286985ddefc53c3a047614568458bb:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-58592/sources/master#f66e4697ae286985ddefc53c3a047614568458bb/gh/vti/rust-test:/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" "+f66e4697ae286985ddefc53c3a047614568458bb-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] 8dac201e4357a58e8f9ce4a7e51dbec8e5deffe649a512ba7db40e45fd6e8377
[INFO] running `"docker" "start" "-a" "8dac201e4357a58e8f9ce4a7e51dbec8e5deffe649a512ba7db40e45fd6e8377"`
[INFO] [stderr]     Checking rust-test v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: value assigned to `a` is never read
[INFO] [stderr]  --> src/main.rs:7:5
[INFO] [stderr]   |
[INFO] [stderr] 7 |     a = a + b;
[INFO] [stderr]   |     ^
[INFO] [stderr]   |
[INFO] [stderr]   = note: #[warn(unused_assignments)] on by default
[INFO] [stderr]   = help: maybe it is overwritten before being read?
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]  --> src/main.rs:5:9
[INFO] [stderr]   |
[INFO] [stderr] 5 |     let mut b = 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: value assigned to `a` is never read
[INFO] [stderr]  --> src/main.rs:7:5
[INFO] [stderr]   |
[INFO] [stderr] 7 |     a = a + b;
[INFO] [stderr]   |     ^
[INFO] [stderr]   |
[INFO] [stderr]   = note: #[warn(unused_assignments)] on by default
[INFO] [stderr]   = help: maybe it is overwritten before being read?
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]  --> src/main.rs:5:9
[INFO] [stderr]   |
[INFO] [stderr] 5 |     let mut b = 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]     Finished dev [unoptimized + debuginfo] target(s) in 0.33s
[INFO] running `"docker" "inspect" "8dac201e4357a58e8f9ce4a7e51dbec8e5deffe649a512ba7db40e45fd6e8377"`
[INFO] running `"docker" "rm" "-f" "8dac201e4357a58e8f9ce4a7e51dbec8e5deffe649a512ba7db40e45fd6e8377"`
[INFO] [stdout] 8dac201e4357a58e8f9ce4a7e51dbec8e5deffe649a512ba7db40e45fd6e8377