[INFO] updating cached repository werner/focusvent_front
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/werner/focusvent_front
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/werner/focusvent_front" "work/ex/beta-1.38-1/sources/1.37.0/gh/werner/focusvent_front"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/werner/focusvent_front'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/werner/focusvent_front" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/werner/focusvent_front"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/werner/focusvent_front'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 0f4612066b8216113d794aaed494eb04e01ad59d
[INFO] sha for GitHub repo werner/focusvent_front: 0f4612066b8216113d794aaed494eb04e01ad59d
[INFO] validating manifest of werner/focusvent_front 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 werner/focusvent_front 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 werner/focusvent_front
[INFO] finished frobbing werner/focusvent_front
[INFO] frobbed toml for werner/focusvent_front written to work/ex/beta-1.38-1/sources/1.37.0/gh/werner/focusvent_front/Cargo.toml
[INFO] started frobbing werner/focusvent_front
[INFO] finished frobbing werner/focusvent_front
[INFO] frobbed toml for werner/focusvent_front written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/werner/focusvent_front/Cargo.toml
[INFO] crate werner/focusvent_front 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 werner/focusvent_front 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-1/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/werner/focusvent_front:/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] 83b86a61f2de946ecc8beb24f68a101849e9c342baaae9c011f079395fbe43c9
[INFO] running `"docker" "start" "-a" "83b86a61f2de946ecc8beb24f68a101849e9c342baaae9c011f079395fbe43c9"`
[INFO] [stderr]    Compiling stdweb v0.4.8
[INFO] [stderr]    Compiling discard v1.0.3
[INFO] [stderr]    Compiling anymap v0.12.1
[INFO] [stderr]    Compiling syn v0.14.5
[INFO] [stderr]    Compiling syn v0.12.15
[INFO] [stderr]    Compiling bytes v0.4.9
[INFO] [stderr]    Compiling bincode v1.0.1
[INFO] [stderr]    Compiling failure v0.1.1
[INFO] [stderr]    Compiling http v0.1.8
[INFO] [stderr]    Compiling serde_derive v1.0.70
[INFO] [stderr]    Compiling stdweb-derive v0.4.0
[INFO] [stderr]    Compiling yew v0.5.0 (https://github.com/DenisKolodin/yew?rev=a5213c57430b2f18539aeb25939bdc8c5c348157#a5213c57)
[INFO] [stderr]    Compiling web_logger v0.1.0
[INFO] [stderr]    Compiling yew_patterns v0.1.0 (https://github.com/hgzimmerman/yew_patterns?rev=63caa9553863382e136ac7b9638c9768422cdd52#63caa955)
[INFO] [stderr]    Compiling yew_router v0.1.0 (https://github.com/hgzimmerman/YewRouter#1f3a26f3)
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> /opt/crater/cargo-home/git/checkouts/yewrouter-c6d9def9135695f5/1f3a26f/src/lib.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(never_type)]
[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 `yew_router`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "83b86a61f2de946ecc8beb24f68a101849e9c342baaae9c011f079395fbe43c9"`
[INFO] running `"docker" "rm" "-f" "83b86a61f2de946ecc8beb24f68a101849e9c342baaae9c011f079395fbe43c9"`
[INFO] [stdout] 83b86a61f2de946ecc8beb24f68a101849e9c342baaae9c011f079395fbe43c9