[INFO] updating cached repository rmsthebest/nullable-first-follow
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/rmsthebest/nullable-first-follow
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/rmsthebest/nullable-first-follow" "work/ex/pr-61100/sources/master#8869ee03d7f258e1b76a11c6fbb01b5708a9f504/gh/rmsthebest/nullable-first-follow"`
[INFO] [stderr] Cloning into 'work/ex/pr-61100/sources/master#8869ee03d7f258e1b76a11c6fbb01b5708a9f504/gh/rmsthebest/nullable-first-follow'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/rmsthebest/nullable-first-follow" "work/ex/pr-61100/sources/try#58b21121d0b447ceb3f1a655155d802191acf044/gh/rmsthebest/nullable-first-follow"`
[INFO] [stderr] Cloning into 'work/ex/pr-61100/sources/try#58b21121d0b447ceb3f1a655155d802191acf044/gh/rmsthebest/nullable-first-follow'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] fac3a77c4de1f7e645a1fbdf8369b31179f69de5
[INFO] sha for GitHub repo rmsthebest/nullable-first-follow: fac3a77c4de1f7e645a1fbdf8369b31179f69de5
[INFO] validating manifest of rmsthebest/nullable-first-follow on toolchain master#8869ee03d7f258e1b76a11c6fbb01b5708a9f504
[INFO] running `"/mnt/crater-raid/crater/work/local/cargo-home/bin/cargo" "+8869ee03d7f258e1b76a11c6fbb01b5708a9f504-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of rmsthebest/nullable-first-follow on toolchain try#58b21121d0b447ceb3f1a655155d802191acf044
[INFO] running `"/mnt/crater-raid/crater/work/local/cargo-home/bin/cargo" "+58b21121d0b447ceb3f1a655155d802191acf044-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing rmsthebest/nullable-first-follow
[INFO] finished frobbing rmsthebest/nullable-first-follow
[INFO] frobbed toml for rmsthebest/nullable-first-follow written to work/ex/pr-61100/sources/master#8869ee03d7f258e1b76a11c6fbb01b5708a9f504/gh/rmsthebest/nullable-first-follow/Cargo.toml
[INFO] started frobbing rmsthebest/nullable-first-follow
[INFO] finished frobbing rmsthebest/nullable-first-follow
[INFO] frobbed toml for rmsthebest/nullable-first-follow written to work/ex/pr-61100/sources/try#58b21121d0b447ceb3f1a655155d802191acf044/gh/rmsthebest/nullable-first-follow/Cargo.toml
[INFO] crate rmsthebest/nullable-first-follow already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/crater-raid/crater/work/local/cargo-home/bin/cargo" "+8869ee03d7f258e1b76a11c6fbb01b5708a9f504-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Blocking waiting for file lock on package cache lock
[INFO] [stderr] error: the lock file /mnt/crater-raid/crater/work/ex/pr-61100/sources/master#8869ee03d7f258e1b76a11c6fbb01b5708a9f504/gh/rmsthebest/nullable-first-follow/Cargo.lock needs to be updated but --locked was passed to prevent this
[INFO] the lockfile is outdated, regenerating it
[INFO] running `"/mnt/crater-raid/crater/work/local/cargo-home/bin/cargo" "+8869ee03d7f258e1b76a11c6fbb01b5708a9f504-alt" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/crater-raid/crater/work/local/cargo-home/bin/cargo" "+58b21121d0b447ceb3f1a655155d802191acf044-alt" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/crater-raid/crater/work/local/cargo-home/bin/cargo" "+8869ee03d7f258e1b76a11c6fbb01b5708a9f504-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/crater-raid/crater/work/local/cargo-home/bin/cargo" "+58b21121d0b447ceb3f1a655155d802191acf044-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] checking rmsthebest/nullable-first-follow against try#58b21121d0b447ceb3f1a655155d802191acf044 for pr-61100
[INFO] running `"docker" "create" "-v" "/mnt/crater-raid/crater/work/local/target-dirs/pr-61100/worker-1/try#58b21121d0b447ceb3f1a655155d802191acf044:/opt/crater/target:rw,Z" "-v" "/mnt/crater-raid/crater/work/ex/pr-61100/sources/try#58b21121d0b447ceb3f1a655155d802191acf044/gh/rmsthebest/nullable-first-follow:/opt/crater/workdir:ro,Z" "-v" "/mnt/crater-raid/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/crater-raid/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" "+58b21121d0b447ceb3f1a655155d802191acf044-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] a6918f34d881d79fa50cdf85cf202e0f3bc2662427609f78eabeb8fe2f7907bf
[INFO] running `"docker" "start" "-a" "a6918f34d881d79fa50cdf85cf202e0f3bc2662427609f78eabeb8fe2f7907bf"`
[INFO] [stderr]    Compiling byteorder v1.3.1
[INFO] [stderr]     Checking hashbrown v0.1.8
[INFO] [stderr]     Checking nff v0.1.2 (/opt/crater/workdir)
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/lib.rs:61:17
[INFO] [stderr]    |
[INFO] [stderr] 61 |             let mut rhs = side.next().expect("Missing right hand side").trim().chars();
[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:61:17
[INFO] [stderr]    |
[INFO] [stderr] 61 |             let mut rhs = side.next().expect("Missing right hand side").trim().chars();
[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 4.51s
[INFO] running `"docker" "inspect" "a6918f34d881d79fa50cdf85cf202e0f3bc2662427609f78eabeb8fe2f7907bf"`
[INFO] running `"docker" "rm" "-f" "a6918f34d881d79fa50cdf85cf202e0f3bc2662427609f78eabeb8fe2f7907bf"`
[INFO] [stdout] a6918f34d881d79fa50cdf85cf202e0f3bc2662427609f78eabeb8fe2f7907bf