[INFO] updating cached repository BooleanCat/prefab
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/BooleanCat/prefab
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/BooleanCat/prefab" "work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/gh/BooleanCat/prefab"`
[INFO] [stderr] Cloning into 'work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/gh/BooleanCat/prefab'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/BooleanCat/prefab" "work/ex/pr-63376/sources/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7/gh/BooleanCat/prefab"`
[INFO] [stderr] Cloning into 'work/ex/pr-63376/sources/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7/gh/BooleanCat/prefab'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 3f2a7b37cd371245f854974ed32a6cea26e47140
[INFO] sha for GitHub repo BooleanCat/prefab: 3f2a7b37cd371245f854974ed32a6cea26e47140
[INFO] validating manifest of BooleanCat/prefab on toolchain master#60960a260f7b5c695fd0717311d72ce62dd4eb43
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+60960a260f7b5c695fd0717311d72ce62dd4eb43-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of BooleanCat/prefab on toolchain try#266783e4e09e4e9d5307c1c8e695659c58bbcac7
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+266783e4e09e4e9d5307c1c8e695659c58bbcac7-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing BooleanCat/prefab
[INFO] finished frobbing BooleanCat/prefab
[INFO] frobbed toml for BooleanCat/prefab written to work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/gh/BooleanCat/prefab/Cargo.toml
[INFO] started frobbing BooleanCat/prefab
[INFO] finished frobbing BooleanCat/prefab
[INFO] frobbed toml for BooleanCat/prefab written to work/ex/pr-63376/sources/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7/gh/BooleanCat/prefab/Cargo.toml
[INFO] crate BooleanCat/prefab already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+60960a260f7b5c695fd0717311d72ce62dd4eb43-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+266783e4e09e4e9d5307c1c8e695659c58bbcac7-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] checking BooleanCat/prefab against master#60960a260f7b5c695fd0717311d72ce62dd4eb43 for pr-63376
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-63376/worker-4/master#60960a260f7b5c695fd0717311d72ce62dd4eb43:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/gh/BooleanCat/prefab:/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" "+60960a260f7b5c695fd0717311d72ce62dd4eb43-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] 2764461c8a5fc23c40734a121e64600bd0aeaf13c82c45de2eefe30b2ae592f6
[INFO] running `"docker" "start" "-a" "2764461c8a5fc23c40734a121e64600bd0aeaf13c82c45de2eefe30b2ae592f6"`
[INFO] [stderr]    Compiling syn v0.15.27
[INFO] [stderr]    Compiling structopt-derive v0.2.14
[INFO] [stderr]    Compiling serde_derive v1.0.89
[INFO] [stderr]     Checking structopt v0.2.14
[INFO] [stderr]     Checking prefab v0.1.0 (/opt/crater/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 36.48s
[INFO] running `"docker" "inspect" "2764461c8a5fc23c40734a121e64600bd0aeaf13c82c45de2eefe30b2ae592f6"`
[INFO] running `"docker" "rm" "-f" "2764461c8a5fc23c40734a121e64600bd0aeaf13c82c45de2eefe30b2ae592f6"`
[INFO] [stdout] 2764461c8a5fc23c40734a121e64600bd0aeaf13c82c45de2eefe30b2ae592f6