[INFO] updating cached repository adamAndMath/traitlit
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/adamAndMath/traitlit
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/adamAndMath/traitlit" "work/ex/beta-1.37-6/sources/1.36.0/gh/adamAndMath/traitlit"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.37-6/sources/1.36.0/gh/adamAndMath/traitlit'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/adamAndMath/traitlit" "work/ex/beta-1.37-6/sources/beta-2019-07-23/gh/adamAndMath/traitlit"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.37-6/sources/beta-2019-07-23/gh/adamAndMath/traitlit'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] ce4e93da4e58b7a3238d648fe3ac0732c2b4c94d
[INFO] sha for GitHub repo adamAndMath/traitlit: ce4e93da4e58b7a3238d648fe3ac0732c2b4c94d
[INFO] validating manifest of adamAndMath/traitlit 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 adamAndMath/traitlit 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 adamAndMath/traitlit
[INFO] finished frobbing adamAndMath/traitlit
[INFO] frobbed toml for adamAndMath/traitlit written to work/ex/beta-1.37-6/sources/1.36.0/gh/adamAndMath/traitlit/Cargo.toml
[INFO] started frobbing adamAndMath/traitlit
[INFO] finished frobbing adamAndMath/traitlit
[INFO] frobbed toml for adamAndMath/traitlit written to work/ex/beta-1.37-6/sources/beta-2019-07-23/gh/adamAndMath/traitlit/Cargo.toml
[INFO] crate adamAndMath/traitlit 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 adamAndMath/traitlit against beta-2019-07-23 for beta-1.37-6
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.37-6/worker-0/beta-2019-07-23:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.37-6/sources/beta-2019-07-23/gh/adamAndMath/traitlit:/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-2019-07-23" "build" "--frozen"`
[INFO] [stdout] 214e0ec648d7c4f8d9382ac4e4f727aeddc3c14677112fd2b0de702a77fc4378
[INFO] running `"docker" "start" "-a" "214e0ec648d7c4f8d9382ac4e4f727aeddc3c14677112fd2b0de702a77fc4378"`
[INFO] [stderr] warning: unused manifest key: package.maintenance
[INFO] [stderr]    Compiling syn v0.15.37
[INFO] [stderr]    Compiling traitlit v0.2.2 (/opt/crater/workdir)
[INFO] [stderr] error[E0554]: #![feature] may not be used on the beta release channel
[INFO] [stderr]  --> src/lib.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(proc_macro_diagnostic)]
[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 `traitlit`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "214e0ec648d7c4f8d9382ac4e4f727aeddc3c14677112fd2b0de702a77fc4378"`
[INFO] running `"docker" "rm" "-f" "214e0ec648d7c4f8d9382ac4e4f727aeddc3c14677112fd2b0de702a77fc4378"`
[INFO] [stdout] 214e0ec648d7c4f8d9382ac4e4f727aeddc3c14677112fd2b0de702a77fc4378