[INFO] updating cached repository tomafro/flashlight
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/tomafro/flashlight
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/tomafro/flashlight" "work/ex/beta-1.37-6/sources/1.36.0/gh/tomafro/flashlight"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.37-6/sources/1.36.0/gh/tomafro/flashlight'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/tomafro/flashlight" "work/ex/beta-1.37-6/sources/beta-2019-07-23/gh/tomafro/flashlight"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.37-6/sources/beta-2019-07-23/gh/tomafro/flashlight'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] e7529d89eb9d97841151555e04a68763e7d1b0c0
[INFO] sha for GitHub repo tomafro/flashlight: e7529d89eb9d97841151555e04a68763e7d1b0c0
[INFO] validating manifest of tomafro/flashlight on toolchain 1.36.0
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.36.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of tomafro/flashlight on toolchain beta-2019-07-23
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-07-23" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing tomafro/flashlight
[INFO] finished frobbing tomafro/flashlight
[INFO] frobbed toml for tomafro/flashlight written to work/ex/beta-1.37-6/sources/1.36.0/gh/tomafro/flashlight/Cargo.toml
[INFO] started frobbing tomafro/flashlight
[INFO] finished frobbing tomafro/flashlight
[INFO] frobbed toml for tomafro/flashlight written to work/ex/beta-1.37-6/sources/beta-2019-07-23/gh/tomafro/flashlight/Cargo.toml
[INFO] crate tomafro/flashlight already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.36.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-07-23" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] testing tomafro/flashlight against 1.36.0 for beta-1.37-6
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.37-6/worker-4/1.36.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.37-6/sources/1.36.0/gh/tomafro/flashlight:/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" "+1.36.0" "build" "--frozen"`
[INFO] [stdout] e1f96ac86d89a1b31df3b6b8a7974bb5b79c776ae2991ffc668f8b69d2b87a09
[INFO] running `"docker" "start" "-a" "e1f96ac86d89a1b31df3b6b8a7974bb5b79c776ae2991ffc668f8b69d2b87a09"`
[INFO] [stderr]    Compiling proc-macro-hack-impl v0.4.0
[INFO] [stderr]    Compiling unindent v0.1.2
[INFO] [stderr]    Compiling num-traits v0.2.2
[INFO] [stderr]    Compiling serde v1.0.34
[INFO] [stderr]    Compiling isatty v0.1.6
[INFO] [stderr]    Compiling serde_derive_internals v0.22.0
[INFO] [stderr]    Compiling proc-macro-hack v0.4.0
[INFO] [stderr]    Compiling indoc-impl v0.2.3
[INFO] [stderr]    Compiling indoc v0.2.3
[INFO] [stderr]    Compiling serde_derive v1.0.34
[INFO] [stderr]    Compiling docopt v0.8.3
[INFO] [stderr]    Compiling serde_json v1.0.13
[INFO] [stderr]    Compiling flashlight v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> src/lib.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(test)]
[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 `flashlight`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "e1f96ac86d89a1b31df3b6b8a7974bb5b79c776ae2991ffc668f8b69d2b87a09"`
[INFO] running `"docker" "rm" "-f" "e1f96ac86d89a1b31df3b6b8a7974bb5b79c776ae2991ffc668f8b69d2b87a09"`
[INFO] [stdout] e1f96ac86d89a1b31df3b6b8a7974bb5b79c776ae2991ffc668f8b69d2b87a09