[INFO] updating cached repository Cam0Cow/BookFace
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/Cam0Cow/BookFace
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/Cam0Cow/BookFace" "work/ex/beta-1.38-1/sources/1.37.0/gh/Cam0Cow/BookFace"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/Cam0Cow/BookFace'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/Cam0Cow/BookFace" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/Cam0Cow/BookFace"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/Cam0Cow/BookFace'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 3a2a3f78323e4bad22e006496cf80d2e4cef896b
[INFO] sha for GitHub repo Cam0Cow/BookFace: 3a2a3f78323e4bad22e006496cf80d2e4cef896b
[INFO] validating manifest of Cam0Cow/BookFace on toolchain 1.37.0
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of Cam0Cow/BookFace on toolchain beta-2019-08-13
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing Cam0Cow/BookFace
[INFO] finished frobbing Cam0Cow/BookFace
[INFO] frobbed toml for Cam0Cow/BookFace written to work/ex/beta-1.38-1/sources/1.37.0/gh/Cam0Cow/BookFace/Cargo.toml
[INFO] started frobbing Cam0Cow/BookFace
[INFO] finished frobbing Cam0Cow/BookFace
[INFO] frobbed toml for Cam0Cow/BookFace written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/Cam0Cow/BookFace/Cargo.toml
[INFO] crate Cam0Cow/BookFace already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] testing Cam0Cow/BookFace against 1.37.0 for beta-1.38-1
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-0/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/Cam0Cow/BookFace:/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=warn" "-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" "+1.37.0" "build" "--frozen"`
[INFO] [stdout] 1e38c7fcceedbcba33436e0c2c1d1712089fc77db0bc9edff238369c31a5e2e7
[INFO] running `"docker" "start" "-a" "1e38c7fcceedbcba33436e0c2c1d1712089fc77db0bc9edff238369c31a5e2e7"`
[INFO] [stderr]    Compiling rocket_codegen v0.1.3
[INFO] [stderr]    Compiling toml v0.2.1
[INFO] [stderr]    Compiling term v0.4.4
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> /opt/crater/cargo-home/registry/src/github.com-1ecc6299db9ec823/rocket_codegen-0.1.3/build.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(slice_patterns)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr] error: Could not compile `rocket_codegen`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "1e38c7fcceedbcba33436e0c2c1d1712089fc77db0bc9edff238369c31a5e2e7"`
[INFO] running `"docker" "rm" "-f" "1e38c7fcceedbcba33436e0c2c1d1712089fc77db0bc9edff238369c31a5e2e7"`
[INFO] [stdout] 1e38c7fcceedbcba33436e0c2c1d1712089fc77db0bc9edff238369c31a5e2e7