[INFO] updating cached repository VaclavStebra/rust-book-references-and-borrowing
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/VaclavStebra/rust-book-references-and-borrowing
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/VaclavStebra/rust-book-references-and-borrowing" "work/ex/pr-62133/sources/master#5f9c0448dde167128d668da4555879f64e56af1d/gh/VaclavStebra/rust-book-references-and-borrowing"`
[INFO] [stderr] Cloning into 'work/ex/pr-62133/sources/master#5f9c0448dde167128d668da4555879f64e56af1d/gh/VaclavStebra/rust-book-references-and-borrowing'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/VaclavStebra/rust-book-references-and-borrowing" "work/ex/pr-62133/sources/try#8ec8125bea94852768b56958f05da47666c21ab0/gh/VaclavStebra/rust-book-references-and-borrowing"`
[INFO] [stderr] Cloning into 'work/ex/pr-62133/sources/try#8ec8125bea94852768b56958f05da47666c21ab0/gh/VaclavStebra/rust-book-references-and-borrowing'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 6a69d6a3a909d36b8b69bc865641a6b3053066d0
[INFO] sha for GitHub repo VaclavStebra/rust-book-references-and-borrowing: 6a69d6a3a909d36b8b69bc865641a6b3053066d0
[INFO] validating manifest of VaclavStebra/rust-book-references-and-borrowing on toolchain master#5f9c0448dde167128d668da4555879f64e56af1d
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+5f9c0448dde167128d668da4555879f64e56af1d-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of VaclavStebra/rust-book-references-and-borrowing on toolchain try#8ec8125bea94852768b56958f05da47666c21ab0
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+8ec8125bea94852768b56958f05da47666c21ab0-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing VaclavStebra/rust-book-references-and-borrowing
[INFO] finished frobbing VaclavStebra/rust-book-references-and-borrowing
[INFO] frobbed toml for VaclavStebra/rust-book-references-and-borrowing written to work/ex/pr-62133/sources/master#5f9c0448dde167128d668da4555879f64e56af1d/gh/VaclavStebra/rust-book-references-and-borrowing/Cargo.toml
[INFO] started frobbing VaclavStebra/rust-book-references-and-borrowing
[INFO] finished frobbing VaclavStebra/rust-book-references-and-borrowing
[INFO] frobbed toml for VaclavStebra/rust-book-references-and-borrowing written to work/ex/pr-62133/sources/try#8ec8125bea94852768b56958f05da47666c21ab0/gh/VaclavStebra/rust-book-references-and-borrowing/Cargo.toml
[INFO] crate VaclavStebra/rust-book-references-and-borrowing already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+5f9c0448dde167128d668da4555879f64e56af1d-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+8ec8125bea94852768b56958f05da47666c21ab0-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] checking VaclavStebra/rust-book-references-and-borrowing against master#5f9c0448dde167128d668da4555879f64e56af1d for pr-62133
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-62133/worker-5/master#5f9c0448dde167128d668da4555879f64e56af1d:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-62133/sources/master#5f9c0448dde167128d668da4555879f64e56af1d/gh/VaclavStebra/rust-book-references-and-borrowing:/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" "+5f9c0448dde167128d668da4555879f64e56af1d-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] 683c1a8468a2aabad2eb9ed86db71a4dfff7584556e0723fcf6fc8f92b20ad0b
[INFO] running `"docker" "start" "-a" "683c1a8468a2aabad2eb9ed86db71a4dfff7584556e0723fcf6fc8f92b20ad0b"`
[INFO] [stderr]     Checking rust-book-references-and-borrowing v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused variable: `r1`
[INFO] [stderr]   --> src/main.rs:20:9
[INFO] [stderr]    |
[INFO] [stderr] 20 |     let r1 = &mut s2;
[INFO] [stderr]    |         ^^ help: consider prefixing with an underscore: `_r1`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `r1`
[INFO] [stderr]   --> src/main.rs:20:9
[INFO] [stderr]    |
[INFO] [stderr] 20 |     let r1 = &mut s2;
[INFO] [stderr]    |         ^^ help: consider prefixing with an underscore: `_r1`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.75s
[INFO] running `"docker" "inspect" "683c1a8468a2aabad2eb9ed86db71a4dfff7584556e0723fcf6fc8f92b20ad0b"`
[INFO] running `"docker" "rm" "-f" "683c1a8468a2aabad2eb9ed86db71a4dfff7584556e0723fcf6fc8f92b20ad0b"`
[INFO] [stdout] 683c1a8468a2aabad2eb9ed86db71a4dfff7584556e0723fcf6fc8f92b20ad0b