[INFO] crate flx 0.2.2 is already in cache
[INFO] extracting crate flx 0.2.2 into work/ex/beta-1.38-1/sources/1.37.0/reg/flx/0.2.2
[INFO] extracting crate flx 0.2.2 into work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/flx/0.2.2
[INFO] validating manifest of flx-0.2.2 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 flx-0.2.2 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 flx-0.2.2
[INFO] finished frobbing flx-0.2.2
[INFO] frobbed toml for flx-0.2.2 written to work/ex/beta-1.38-1/sources/1.37.0/reg/flx/0.2.2/Cargo.toml
[INFO] started frobbing flx-0.2.2
[INFO] finished frobbing flx-0.2.2
[INFO] frobbed toml for flx-0.2.2 written to work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/flx/0.2.2/Cargo.toml
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[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 flx-0.2.2 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-6/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/reg/flx/0.2.2:/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] f90bddd4db1625afc44c7a83c88369f6d05dc8ee6b310a81ff2c0dab4bf73919
[INFO] running `"docker" "start" "-a" "f90bddd4db1625afc44c7a83c88369f6d05dc8ee6b310a81ff2c0dab4bf73919"`
[INFO] [stderr]    Compiling flx v0.2.2 (/opt/crater/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.91s
[INFO] running `"docker" "inspect" "f90bddd4db1625afc44c7a83c88369f6d05dc8ee6b310a81ff2c0dab4bf73919"`
[INFO] running `"docker" "rm" "-f" "f90bddd4db1625afc44c7a83c88369f6d05dc8ee6b310a81ff2c0dab4bf73919"`
[INFO] [stdout] f90bddd4db1625afc44c7a83c88369f6d05dc8ee6b310a81ff2c0dab4bf73919
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-6/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/reg/flx/0.2.2:/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" "test" "--frozen" "--no-run"`
[INFO] [stdout] 7cc674547d42c93f2c9a44f37253390acd2ba6ae0a905d8d65f802aeee58a5ab
[INFO] running `"docker" "start" "-a" "7cc674547d42c93f2c9a44f37253390acd2ba6ae0a905d8d65f802aeee58a5ab"`
[INFO] [stderr]    Compiling flx v0.2.2 (/opt/crater/workdir)
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> src/lib.rs:7:19
[INFO] [stderr]   |
[INFO] [stderr] 7 | #![cfg_attr(test, 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 `flx`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "7cc674547d42c93f2c9a44f37253390acd2ba6ae0a905d8d65f802aeee58a5ab"`
[INFO] running `"docker" "rm" "-f" "7cc674547d42c93f2c9a44f37253390acd2ba6ae0a905d8d65f802aeee58a5ab"`
[INFO] [stdout] 7cc674547d42c93f2c9a44f37253390acd2ba6ae0a905d8d65f802aeee58a5ab