[INFO] updating cached repository luzzif/kore
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/luzzif/kore
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/luzzif/kore" "work/ex/beta-1.38-1/sources/1.37.0/gh/luzzif/kore"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/luzzif/kore'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/luzzif/kore" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/luzzif/kore"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/luzzif/kore'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 3ac122b745376c285f9190356807dfd3dc12a0dc
[INFO] sha for GitHub repo luzzif/kore: 3ac122b745376c285f9190356807dfd3dc12a0dc
[INFO] validating manifest of luzzif/kore 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 luzzif/kore 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 luzzif/kore
[INFO] finished frobbing luzzif/kore
[INFO] frobbed toml for luzzif/kore written to work/ex/beta-1.38-1/sources/1.37.0/gh/luzzif/kore/Cargo.toml
[INFO] started frobbing luzzif/kore
[INFO] finished frobbing luzzif/kore
[INFO] frobbed toml for luzzif/kore written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/luzzif/kore/Cargo.toml
[INFO] crate luzzif/kore 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 luzzif/kore 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-7/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/luzzif/kore:/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] 608121a1da0f5013754b76973a72a57a29bbdff715627f3227113bebb33e486d
[INFO] running `"docker" "start" "-a" "608121a1da0f5013754b76973a72a57a29bbdff715627f3227113bebb33e486d"`
[INFO] [stderr]    Compiling version_check v0.1.4
[INFO] [stderr]    Compiling spin v0.4.9
[INFO] [stderr]    Compiling volatile v0.2.4
[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/spin-0.4.9/src/lib.rs:6:35
[INFO] [stderr]   |
[INFO] [stderr] 6 | #![cfg_attr(feature = "const_fn", feature(const_fn))]
[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 `spin`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "608121a1da0f5013754b76973a72a57a29bbdff715627f3227113bebb33e486d"`
[INFO] running `"docker" "rm" "-f" "608121a1da0f5013754b76973a72a57a29bbdff715627f3227113bebb33e486d"`
[INFO] [stdout] 608121a1da0f5013754b76973a72a57a29bbdff715627f3227113bebb33e486d