[INFO] crate mock_me 0.2.3 is already in cache
[INFO] testing mock_me-0.2.3 against beta-2019-09-28 for beta-1.39-1
[INFO] extracting crate mock_me 0.2.3 into work/builds/worker-7/source
[INFO] validating manifest of crates.io crate mock_me 0.2.3 on toolchain beta-2019-09-28
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+beta-2019-09-28" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking crates.io crate mock_me 0.2.3
[INFO] finished tweaking crates.io crate mock_me 0.2.3
[INFO] tweaked toml for crates.io crate mock_me 0.2.3 written to work/builds/worker-7/source/Cargo.toml
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+beta-2019-09-28" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+beta-2019-09-28" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr] warning: library `mock_me` should only specify `proc-macro = true` instead of setting `crate-type`
[INFO] running `"docker" "create" "-v" "/big/crater/work/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/big/crater/work/builds/worker-7/source:/opt/rustwide/workdir:ro,Z" "-v" "/big/crater/work/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/big/crater/work/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2019-09-28" "build" "--frozen"`
[INFO] [stdout] 2b08cd61a328ddcdee30d47e7199b8f15a5129e1540f3ba74898c730bb6c999a
[INFO] running `"docker" "start" "-a" "2b08cd61a328ddcdee30d47e7199b8f15a5129e1540f3ba74898c730bb6c999a"`
[INFO] [stderr] warning: library `mock_me` should only specify `proc-macro = true` instead of setting `crate-type`
[INFO] [stderr]    Compiling mock_me_test_context v0.1.2
[INFO] [stderr]    Compiling mock_me v0.2.3 (/opt/rustwide/workdir)
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stderr]   --> src/lib.rs:47:1
[INFO] [stderr]    |
[INFO] [stderr] 47 | #![feature(proc_macro)]
[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 `mock_me`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "2b08cd61a328ddcdee30d47e7199b8f15a5129e1540f3ba74898c730bb6c999a"`
[INFO] running `"docker" "rm" "-f" "2b08cd61a328ddcdee30d47e7199b8f15a5129e1540f3ba74898c730bb6c999a"`
[INFO] [stdout] 2b08cd61a328ddcdee30d47e7199b8f15a5129e1540f3ba74898c730bb6c999a