[INFO] updating cached repository PolySync/howser
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/PolySync/howser
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/PolySync/howser" "work/ex/beta-1.38-1/sources/1.37.0/gh/PolySync/howser"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/PolySync/howser'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/PolySync/howser" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/PolySync/howser"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/PolySync/howser'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] d8e1d2ebb6a1534b4104d614108f6a75c3966faa
[INFO] sha for GitHub repo PolySync/howser: d8e1d2ebb6a1534b4104d614108f6a75c3966faa
[INFO] validating manifest of PolySync/howser 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 PolySync/howser 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 PolySync/howser
[INFO] finished frobbing PolySync/howser
[INFO] frobbed toml for PolySync/howser written to work/ex/beta-1.38-1/sources/1.37.0/gh/PolySync/howser/Cargo.toml
[INFO] started frobbing PolySync/howser
[INFO] finished frobbing PolySync/howser
[INFO] frobbed toml for PolySync/howser written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/PolySync/howser/Cargo.toml
[INFO] crate PolySync/howser 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] testing PolySync/howser against beta-2019-08-13 for beta-1.38-1
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-2/beta-2019-08-13:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/PolySync/howser:/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" "+beta-2019-08-13" "build" "--frozen"`
[INFO] [stdout] 39d83ce9d007b6819abb931a47f4f646573b7c57ba92a3730b72cf748ee878f7
[INFO] running `"docker" "start" "-a" "39d83ce9d007b6819abb931a47f4f646573b7c57ba92a3730b72cf748ee878f7"`
[INFO] [stderr]    Compiling doogie v1.0.0 (https://github.com/PolySync/doogie?tag=1.0.0#77015a45)
[INFO] [stderr]    Compiling clap v2.29.4
[INFO] [stderr]    Compiling num-bigint v0.1.44
[INFO] [stderr]    Compiling regex v0.2.11
[INFO] [stderr]    Compiling toml v0.4.6
[INFO] [stderr]    Compiling env_logger v0.5.10
[INFO] [stderr]    Compiling num-rational v0.1.42
[INFO] [stderr]    Compiling num v0.1.42
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stderr]  --> /opt/crater/cargo-home/git/checkouts/doogie-52d9eefd866dafa0/77015a4/src/lib.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(vec_remove_item)]
[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 `doogie`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "39d83ce9d007b6819abb931a47f4f646573b7c57ba92a3730b72cf748ee878f7"`
[INFO] running `"docker" "rm" "-f" "39d83ce9d007b6819abb931a47f4f646573b7c57ba92a3730b72cf748ee878f7"`
[INFO] [stdout] 39d83ce9d007b6819abb931a47f4f646573b7c57ba92a3730b72cf748ee878f7