[INFO] crate r4 1.0.1 is already in cache
[INFO] extracting crate r4 1.0.1 into work/ex/pr-60039-1/sources/master#e305df1846a6d985315917ae0c81b74af8b4e641/reg/r4/1.0.1
[INFO] extracting crate r4 1.0.1 into work/ex/pr-60039-1/sources/try#99a7498759a22b5684caf798a98b7e90ad9d2443/reg/r4/1.0.1
[INFO] validating manifest of r4-1.0.1 on toolchain master#e305df1846a6d985315917ae0c81b74af8b4e641
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+e305df1846a6d985315917ae0c81b74af8b4e641-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of r4-1.0.1 on toolchain try#99a7498759a22b5684caf798a98b7e90ad9d2443
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+99a7498759a22b5684caf798a98b7e90ad9d2443-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing r4-1.0.1
[INFO] finished frobbing r4-1.0.1
[INFO] frobbed toml for r4-1.0.1 written to work/ex/pr-60039-1/sources/master#e305df1846a6d985315917ae0c81b74af8b4e641/reg/r4/1.0.1/Cargo.toml
[INFO] started frobbing r4-1.0.1
[INFO] finished frobbing r4-1.0.1
[INFO] frobbed toml for r4-1.0.1 written to work/ex/pr-60039-1/sources/try#99a7498759a22b5684caf798a98b7e90ad9d2443/reg/r4/1.0.1/Cargo.toml
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+e305df1846a6d985315917ae0c81b74af8b4e641-alt" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+99a7498759a22b5684caf798a98b7e90ad9d2443-alt" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+e305df1846a6d985315917ae0c81b74af8b4e641-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+99a7498759a22b5684caf798a98b7e90ad9d2443-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] checking r4-1.0.1 against master#e305df1846a6d985315917ae0c81b74af8b4e641 for pr-60039-1
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-60039-1/worker-6/master#e305df1846a6d985315917ae0c81b74af8b4e641:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-60039-1/sources/master#e305df1846a6d985315917ae0c81b74af8b4e641/reg/r4/1.0.1:/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" "+e305df1846a6d985315917ae0c81b74af8b4e641-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] 372fcfa017ab6c904fba2bd33f73df8ff7a1d3799b2d81122f9da54ff48b3cbe
[INFO] running `"docker" "start" "-a" "372fcfa017ab6c904fba2bd33f73df8ff7a1d3799b2d81122f9da54ff48b3cbe"`
[INFO] [stderr]     Checking r4 v1.0.1 (/opt/crater/workdir)
[INFO] [stderr] warning: unused variable: `i`
[INFO] [stderr]    --> src/lib.rs:407:34
[INFO] [stderr]     |
[INFO] [stderr] 407 |                     iterate![for i in 0..4;
[INFO] [stderr]     |                                  ^ help: consider prefixing with an underscore: `_i`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `x`
[INFO] [stderr]    --> src/lib.rs:433:34
[INFO] [stderr]     |
[INFO] [stderr] 433 |                     iterate![for x in vs.iter();
[INFO] [stderr]     |                                  ^ help: consider prefixing with an underscore: `_x`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `x`
[INFO] [stderr]    --> src/lib.rs:443:34
[INFO] [stderr]     |
[INFO] [stderr] 443 |                     iterate![for x in vs.iter();
[INFO] [stderr]     |                                  ^ help: consider prefixing with an underscore: `_x`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `a`
[INFO] [stderr]    --> src/lib.rs:474:34
[INFO] [stderr]     |
[INFO] [stderr] 474 |                              let a = *x + 3;
[INFO] [stderr]     |                                  ^ help: consider prefixing with an underscore: `_a`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `a`
[INFO] [stderr]    --> src/lib.rs:489:34
[INFO] [stderr]     |
[INFO] [stderr] 489 |                              let a = *x + 3;
[INFO] [stderr]     |                                  ^ help: consider prefixing with an underscore: `_a`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `y`
[INFO] [stderr]    --> src/lib.rs:506:34
[INFO] [stderr]     |
[INFO] [stderr] 506 |                              for y in vs.iter();
[INFO] [stderr]     |                                  ^ help: consider prefixing with an underscore: `_y`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `x`
[INFO] [stderr]    --> src/lib.rs:522:34
[INFO] [stderr]     |
[INFO] [stderr] 522 |                              let x = *x + 1;
[INFO] [stderr]     |                                  ^ help: consider prefixing with an underscore: `_x`
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.58s
[INFO] running `"docker" "inspect" "372fcfa017ab6c904fba2bd33f73df8ff7a1d3799b2d81122f9da54ff48b3cbe"`
[INFO] running `"docker" "rm" "-f" "372fcfa017ab6c904fba2bd33f73df8ff7a1d3799b2d81122f9da54ff48b3cbe"`
[INFO] [stdout] 372fcfa017ab6c904fba2bd33f73df8ff7a1d3799b2d81122f9da54ff48b3cbe