[INFO] updating cached repository pandaman64/cps
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/pandaman64/cps
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/pandaman64/cps" "work/ex/beta-1.38-1/sources/1.37.0/gh/pandaman64/cps"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/pandaman64/cps'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/pandaman64/cps" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/pandaman64/cps"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/pandaman64/cps'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 2879fa7f4579e3fe8cae7be0f99a711e6657f698
[INFO] sha for GitHub repo pandaman64/cps: 2879fa7f4579e3fe8cae7be0f99a711e6657f698
[INFO] validating manifest of pandaman64/cps 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 pandaman64/cps 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 pandaman64/cps
[INFO] removed workspace from pandaman64/cps
[INFO] finished frobbing pandaman64/cps
[INFO] frobbed toml for pandaman64/cps written to work/ex/beta-1.38-1/sources/1.37.0/gh/pandaman64/cps/Cargo.toml
[INFO] started frobbing pandaman64/cps
[INFO] removed workspace from pandaman64/cps
[INFO] finished frobbing pandaman64/cps
[INFO] frobbed toml for pandaman64/cps written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/pandaman64/cps/Cargo.toml
[INFO] crate pandaman64/cps 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 pandaman64/cps 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-5/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/pandaman64/cps:/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] f6c4f58734c12b10b1255625b942688ce6afa75e60047bdf88709f5fa868d556
[INFO] running `"docker" "start" "-a" "f6c4f58734c12b10b1255625b942688ce6afa75e60047bdf88709f5fa868d556"`
[INFO] [stderr]    Compiling syn v0.15.34
[INFO] [stderr]    Compiling pin-utils v0.1.0-alpha.4
[INFO] [stderr]    Compiling quote v0.6.12
[INFO] [stderr]    Compiling proc-macro-hack v0.5.7
[INFO] [stderr]    Compiling eff-attr v0.0.6
[INFO] [stderr]    Compiling eff v0.0.8 (/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(generator_trait, 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 `eff`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "f6c4f58734c12b10b1255625b942688ce6afa75e60047bdf88709f5fa868d556"`
[INFO] running `"docker" "rm" "-f" "f6c4f58734c12b10b1255625b942688ce6afa75e60047bdf88709f5fa868d556"`
[INFO] [stdout] f6c4f58734c12b10b1255625b942688ce6afa75e60047bdf88709f5fa868d556