[INFO] fetching crate tap 0.3.0...
[INFO] extracting crate tap 0.3.0 into work/ex/pr-58899/sources/master#c0086b9e8972fef9fd4af24bae20d45021ed06c6/reg/tap/0.3.0
[INFO] extracting crate tap 0.3.0 into work/ex/pr-58899/sources/try#290ac7b29f41ff9fa5232f9a1116ea71a3501063/reg/tap/0.3.0
[INFO] validating manifest of tap-0.3.0 on toolchain master#c0086b9e8972fef9fd4af24bae20d45021ed06c6
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+c0086b9e8972fef9fd4af24bae20d45021ed06c6-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of tap-0.3.0 on toolchain try#290ac7b29f41ff9fa5232f9a1116ea71a3501063
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+290ac7b29f41ff9fa5232f9a1116ea71a3501063-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing tap-0.3.0
[INFO] finished frobbing tap-0.3.0
[INFO] frobbed toml for tap-0.3.0 written to work/ex/pr-58899/sources/master#c0086b9e8972fef9fd4af24bae20d45021ed06c6/reg/tap/0.3.0/Cargo.toml
[INFO] started frobbing tap-0.3.0
[INFO] finished frobbing tap-0.3.0
[INFO] frobbed toml for tap-0.3.0 written to work/ex/pr-58899/sources/try#290ac7b29f41ff9fa5232f9a1116ea71a3501063/reg/tap/0.3.0/Cargo.toml
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+c0086b9e8972fef9fd4af24bae20d45021ed06c6-alt" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+290ac7b29f41ff9fa5232f9a1116ea71a3501063-alt" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+c0086b9e8972fef9fd4af24bae20d45021ed06c6-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+290ac7b29f41ff9fa5232f9a1116ea71a3501063-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] checking tap-0.3.0 against master#c0086b9e8972fef9fd4af24bae20d45021ed06c6 for pr-58899
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-58899/worker-5/master#c0086b9e8972fef9fd4af24bae20d45021ed06c6:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-58899/sources/master#c0086b9e8972fef9fd4af24bae20d45021ed06c6/reg/tap/0.3.0:/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" "+c0086b9e8972fef9fd4af24bae20d45021ed06c6-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] 17e745c10a90b250b76f2773807b08f4735703dc5ded45853a47465dce09387d
[INFO] running `"docker" "start" "-a" "17e745c10a90b250b76f2773807b08f4735703dc5ded45853a47465dce09387d"`
[INFO] [stderr]     Checking tap v0.3.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused `#[macro_use]` import
[INFO] [stderr]   --> src/lib.rs:14:18
[INFO] [stderr]    |
[INFO] [stderr] 14 | #[cfg_attr(test, macro_use)]
[INFO] [stderr]    |                  ^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_imports)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/lib.rs:78:21
[INFO] [stderr]    |
[INFO] [stderr] 78 |         if let Some(mut val) = self.as_mut() {
[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/lib.rs:78:21
[INFO] [stderr]    |
[INFO] [stderr] 78 |         if let Some(mut val) = self.as_mut() {
[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/lib.rs:141:33
[INFO] [stderr]     |
[INFO] [stderr] 141 |         let mutated = base.tap(|mut arr| for elt in arr.iter_mut() {
[INFO] [stderr]     |                                 ----^^^
[INFO] [stderr]     |                                 |
[INFO] [stderr]     |                                 help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.80s
[INFO] running `"docker" "inspect" "17e745c10a90b250b76f2773807b08f4735703dc5ded45853a47465dce09387d"`
[INFO] running `"docker" "rm" "-f" "17e745c10a90b250b76f2773807b08f4735703dc5ded45853a47465dce09387d"`
[INFO] [stdout] 17e745c10a90b250b76f2773807b08f4735703dc5ded45853a47465dce09387d